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Sample records for hen flocks housed

  1. Effect of rearing factors on the prevalence of floor eggs, cloacal cannibalism and feather pecking in commercial flocks of loose housed laying hens.

    Science.gov (United States)

    Gunnarsson, S; Keeling, L J; Svedberg, J

    1999-03-01

    1. Effects of rearing conditions on behavioural problems were investigated in a cohort study of commercial flocks of laying hens housed in 2 different loose housing systems. The sample population was 120 385 laying hens from 59 flocks of various hybrids at 21 different farms. 2. Logistic regression modelling was used to test the effects of selected factors on floor eggs, cloacal cannibalism and feather pecking. In addition to early access to perches or litter, models included hybrid, stocking density, group size, housing system, age at delivery, identical housing system at the rearing farm and at the production farm and, in models for floor eggs and cloacal cannibalism, nest area per hen. Odds ratios were calculated from the results of the models to allow risk assessment. 3. No significant correlations were found between the prevalence of floor eggs, cloacal cannibalism and feather pecking. 4. Access to perches from not later than the 4th week of age decreased the prevalence of floor eggs during the period from start-of-lay until 35 weeks of age, odds ratio 0-30 (Pfeather pecking.

  2. Feather-pecking and injurious pecking in organic laying hens in 107 flocks from eight European countries

    DEFF Research Database (Denmark)

    Bestman, M.; Verwer, Cynthia; Brenninkmeyer, Christine

    2017-01-01

    Feather-pecking and cannibalism may reduce the potential of organic husbandry to enhance the welfare of laying hens. We report risk factors for these issues based on a large survey of 107 commercial flocks in eight European countries. Information was collected regarding housing, management...... and flock characteristics (age, genotype). Near the end of lay, 50 hens per flock were assessed for plumage condition and wounds. Potential influencing factors were screened and submitted to a multivariate model. The majority of the flocks (81%) consisted of brown genotypes and were found in six countries...

  3. Causes of mortality in laying hens in different housing systems in 2001 to 2004

    Directory of Open Access Journals (Sweden)

    Etterlin Pernille

    2009-01-01

    Full Text Available Abstract Background The husbandry systems for laying hens were changed in Sweden during the years 2001 – 2004, and an increase in the number of submissions for necropsy from laying hen farms was noted. Hence, this study was initiated to compare causes of mortality in different housing systems for commercial laying hens during this change. Methods Based on results from routine necropsies of 914 laying hens performed at the National Veterinary Institute (SVA in Uppsala, Sweden between 2001 and 2004, a retrospective study on the occurrence of diseases and cannibalism, i.e., pecking leading to mortality, in different housing systems was carried out. Using the number of disease outbreaks in caged flocks as the baseline, the expected number of flocks with a certain category of disease in the other housing systems was estimated having regard to the total number of birds in the population. Whether the actual number of flocks significantly exceeded the expected number was determined using a Poisson distribution for the variance of the baseline number, a continuity correction and the exact value for the Poisson distribution function in Excel 2000. Results Common causes of mortality in necropsied laying hens included colibacillosis, erysipelas, coccidiosis, red mite infestation, lymphoid leukosis and cannibalism. Less common diagnoses were Newcastle Disease, pasteurellosis and botulism. Considering the size of the populations in the different housing systems, a larger proportion of laying hens than expected was submitted for necropsy from litter-based systems and free range production compared to hens in cages (P P P Conclusion The results of the present study indicated that during 2001–2004 laying hens housed in litter-based housing systems, with or without access to outdoor areas, were at higher risk of infectious diseases and cannibalistic behaviour compared to laying hens in cages. Future research should focus on finding suitable prophylactic

  4. Specific characteristics of the aviary housing system affect plumage condition, mortality and production in laying hens.

    Science.gov (United States)

    Heerkens, Jasper L T; Delezie, Evelyne; Kempen, Ine; Zoons, Johan; Ampe, Bart; Rodenburg, T Bas; Tuyttens, Frank A M

    2015-09-01

    Feather pecking and high mortality levels are significant welfare problems in non-cage housing systems for laying hens. The aim of this study was to identify husbandry-related risk factors for feather damage, mortality, and egg laying performance in laying hens housed in the multi-tier non-cage housing systems known as aviaries. Factors tested included type of system flooring, degree of red mite infestation, and access to free-range areas. Information on housing characteristics, management, and performance in Belgian aviaries (N=47 flocks) were obtained from a questionnaire, farm records, and farm visits. Plumage condition and pecking wounds were scored in 50 randomly selected 60-week-old hens per flock. Associations between plumage condition, wounds, performance, mortality, and possible risk factors were investigated using a linear model with a stepwise model selection procedure. Many flocks exhibited a poor plumage condition and a high prevalence of wounds, with considerable variation between flocks. Better plumage condition was found in wire mesh aviaries (Pfeather cover had lower levels of mortality (Pnest perches. Wire mesh flooring in particular seems to have several health, welfare, and performance benefits in comparison to plastic slats, possibly related to decreased feather pecking, better hygiene, and fewer red mite infestations. This suggests that adjustments to the aviary housing design may further improve laying hen welfare and performance. © 2015 Poultry Science Association Inc.

  5. Role of batch depletion of broiler houses on the occurrence of Campylobacter spp. in chicken flocks

    DEFF Research Database (Denmark)

    Hald, Birthe; Rattenborg, Erik; Madsen, Mogens

    2001-01-01

    Aims: The effect of batch depletion of broiler houses for campylobacter occurrence in broiler flocks was estimated in 10 flocks, each comprising a separate female and male batch. Methods and Results: The chicks were sampled first bq; cloacal swabs in the broiler houses before the start...... that batch depletion of broiler houses increased the prevalence of Campylobacter spp.-infected broilers in the flocks, that the introduction occurred a hen catching the first batch, and that campylobacter spreads through the entire flock within a week. Significance and Impact of the Study: The results from...

  6. Implications for Welfare, Productivity and Sustainability of the Variation in Reported Levels of Mortality for Laying Hen Flocks Kept in Different Housing Systems: A Meta-Analysis of Ten Studies.

    Science.gov (United States)

    Weeks, Claire A; Lambton, Sarah L; Williams, Adrian G

    2016-01-01

    Data from ten sources comprising 3,851 flocks were modelled to identify variation in levels of mortality in laying hens. The predicted increase with age was curvilinear with significant variation between the seven breed categories. Mortality was higher in loose housing systems than in cages and variable within system, confirming previous reports. Cumulative mortality (CM) was higher in flocks with intact beaks (χ2 = 6.03; df 1; p = 0.014) than in those with trimmed beaks. Most data were available for free-range systems (2,823 flocks), where producer recorded CM at 60-80 weeks of age averaged 10% but with a range from 0% to 69.3%. Life cycle assessment showed that the main effect of increased levels of hen mortality is to increase the relative contribution of breeding overheads, so increasing environmental burdens per unit of production. Reducing CM to levels currently achieved by the 1st quartile could reduce flock greenhouse gas emissions by as much as 25%. Concurrently this would enhance hen welfare and better meet the expectation of egg consumers. More research to understand the genetic x environment interaction and detailed records of the causes of mortality is required so that improved genotypes can be developed for different systems and different breeds can be better managed within systems.

  7. Implications for Welfare, Productivity and Sustainability of the Variation in Reported Levels of Mortality for Laying Hen Flocks Kept in Different Housing Systems: A Meta-Analysis of Ten Studies.

    Directory of Open Access Journals (Sweden)

    Claire A Weeks

    Full Text Available Data from ten sources comprising 3,851 flocks were modelled to identify variation in levels of mortality in laying hens. The predicted increase with age was curvilinear with significant variation between the seven breed categories. Mortality was higher in loose housing systems than in cages and variable within system, confirming previous reports. Cumulative mortality (CM was higher in flocks with intact beaks (χ2 = 6.03; df 1; p = 0.014 than in those with trimmed beaks. Most data were available for free-range systems (2,823 flocks, where producer recorded CM at 60-80 weeks of age averaged 10% but with a range from 0% to 69.3%. Life cycle assessment showed that the main effect of increased levels of hen mortality is to increase the relative contribution of breeding overheads, so increasing environmental burdens per unit of production. Reducing CM to levels currently achieved by the 1st quartile could reduce flock greenhouse gas emissions by as much as 25%. Concurrently this would enhance hen welfare and better meet the expectation of egg consumers. More research to understand the genetic x environment interaction and detailed records of the causes of mortality is required so that improved genotypes can be developed for different systems and different breeds can be better managed within systems.

  8. A comparison of transmission characteristics of Salmonella enterica serovar Enteritidis between pair-housed and group-housed laying hens

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    Thomas Ekelijn

    2011-02-01

    Full Text Available Abstract Human cases of bacterial gastro-enteritis are often caused by the consumption of eggs contaminated with Salmonella species, mainly Salmonella enterica serovar Enteriditis (Salmonella Enteritidis. To reduce human exposure, in several countries worldwide surveillance programmes are implemented to detect colonized layer flocks. The sampling schemes are based on the within-flock prevalence, and, as this changes over time, knowledge of the within-flock dynamics of Salmonella Enteritidis is required. Transmission of Salmonella Enteritidis has been quantified in pairs of layers, but the question is whether the dynamics in pairs is comparable to transmission in large groups, which are more representative for commercial layer flocks. The aim of this study was to compare results of transmission experiments between pairs and groups of laying hens. Experimental groups of either 2 or 200 hens were housed at similar densities, and 1 or 4 hens were inoculated with Salmonella Enteritidis, respectively. Excretion was monitored by regularly testing of fecal samples for the presence of Salmonella Enteritidis. Using mathematical modeling, the group experiments were simulated with transmission parameter estimates from the pairwise experiments. Transmission of the bacteria did not differ significantly between pairs or groups. This finding suggests that the transmission parameter estimates from small-scale experiments might be extrapolated to the field situation.

  9. Effects of stocking density, flock size and management on the welfare of laying hens in single-tier aviaries.

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    Nicol, C J; Brown, S N; Glen, E; Pope, S J; Short, F J; Warriss, P D; Zimmerman, P H; Wilkins, L J

    2006-04-01

    Management practices, stocking rate and flock size may affect laying hen welfare but there have been few replicated studies in commercial non-cage systems that investigate this. This study used a broad range of physical and physiological indicators to assess the welfare of hens in 36 commercial flocks. Six laying period treatments were examined with each treatment replicated 6 times. It was not possible to randomly allocate treatments to houses, so treatment and house were largely confounded. Three stocking rates were compared: 7 birds/m(2) (n = 2450), 9 birds/m(2) (n = 3150) and 12 birds/m(2) in either small (n = 2450) or large (n = 4200) flocks. In addition, at 12 birds/m(2), in both small and large flocks, birds were subjected to either standard (SM) or modified (MM) management. MM flocks had nipple drinkers and no nest-box lights. Bone strength, fracture incidence, heterophil:lymphocyte (H:L) ratio, live weight, organ weights, serum creatine, serum osmolality, muscle pH and faecal corticosterone were measured on samples of birds at the end of the rearing period and at the end of lay. During the laying period, mortality, production and integument condition were recorded at regular intervals. Birds housed at 9 birds/m(2) had higher mortality than birds housed at 12 birds/m(2) by the end of lay, but not higher than birds housed at 7 birds/m(2). Birds housed at 7 and 9 birds/m(2) had lower percent liver weight, and worse plumage condition than most of the 12 bird/m(2) treatments. Modified management tended to improve plumage condition. There were no clear effects of flock size on the welfare indicators recorded. At the end of the rearing period fracture incidence was almost negligible and H:L ratio was within a normal range. By the end of lay fracture incidence was 60% and H:L ratio was high, with no treatment effect for either measure. This, together with information on faecal corticosterone, feather loss and mortality, suggests that the welfare of birds in all

  10. Prevalence of nematode infection and faecal egg counts in free-range laying hens: relations to housing and husbandry.

    Science.gov (United States)

    Sherwin, C M; Nasr, M A F; Gale, E; Petek, M; Stafford, K; Turp, M; Coles, G C

    2013-01-01

    1. Faecal samples from 19 commercial, 65 week old free-range egg laying flocks were examined to assess the prevalence and number of parasitic nematode eggs. Data were collected to characterise the housing, husbandry, behaviour and welfare of the flocks to examine possible relationships with the egg counts. 2. Eggs of at least one genus of nematode were present in the faeces of all 19 flocks. Heterakis eggs were detected in 17 (89%) flocks, Ascaridia in 16 (84%), Trichostrongylus in 9 (47%), and Syngamus in 6 (32%). Faecal egg counts (FEC) were greatest for Ascaridia and Heterakis. 3. For each nematode genus, there was no significant difference in FEC between organic (N = 9) and non-organic (N = 10) flocks, or between static (N = 8) and mobile (N = 11) flocks. 4. FEC were correlated with a range of housing, husbandry and management practices which varied between the nematode genus and included depth of the litter, percentage of hens using the range, and number of dead hens. Statistical analysis indicated relationships with FEC that included light intensity above the feeder, indoor and outdoor stocking density, fearfulness in the shed and on the range, distance to the nearest shelter, and swollen toes. 5. None of the FEC for any of the genera was correlated with weekly egg production or cumulative mortality. 6. Although nematode FEC were highly prevalent among the flocks, the overall lack of relation to other welfare and production measures suggests that these infections were not severe.

  11. Detection of the Newcastle disease virus and its effect on development of post-vaccination immunity in a commercial flock of laying hens

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    Jana Jeřábková

    2012-01-01

    Full Text Available The aim of this study was to monitor the concentration of antibodies against Newcastle disease after vaccination of laying hens at the beginning and in the end of the laying period. The study was carried out in one commercial flock of laying hens in Opatovice in the Czech Republic in the years 2008-2010. A total of 280 samples of blood sera were taken from laying hens coming from four poultry houses. The sera were tested by the haemagglutination inhibition test according to the OIE Manual. Virological testing was conducted as a consequence of atypical results of serological testing. Newcastle disease virus RNA was proved by the RT-nested PCR method in the pooled tissue samples of 5 hens, in the samples of intestines with ileocaecal tonsila, in trachea and also in one swab sample from the environment of one house. Based on sequencing analysis and subsequent phylogenetic analysis, the virus was identified as a low pathogenic strain of paramyxovirus (PMV-1. This low pathogenic strain did not have any impact on the health of laying hens.

  12. Health and Welfare in Dutch Organic Laying Hens

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    Monique Bestman

    2014-06-01

    Full Text Available From 2007–2008, data on animal health and welfare and farm management during rearing and laying periods were collected from 49 flocks of organic laying hens in the Netherlands. Our aim was to investigate how organic egg farms performed in terms of animal health and welfare and which farm factors affected this performance. The flocks in our study were kept on farms with 34 to 25,000 hens (average 9,300 hens. Seventy-one percent of the flocks consisted of ‘silver hybrids’: white hens that lay brown eggs. Fifty-five percent of the flocks were kept in floor-based housing and 45% of the flocks in aviaries. No relation was found between the amount of time spent outdoors during the laying period and mortality at 60 weeks. Flocks that used their outdoor run more intensively had better feather scores. In 40% of the flocks there was mortality caused by predators. The average feed intake was 129 g/day at 30 weeks and 133 g/day at 60 weeks of age. The average percentage of mislaid eggs decreased from three at 30 weeks to two at 60 weeks. The average mortality was 7.8% at 60 weeks. Twenty-five percent of the flocks were not treated for worms in their first 50 weeks. Flubenol© was applied to the flocks that were treated. Ten percent of the flocks followed Flubenol© instructions for use and were wormed five or more times. The other 65% percent were treated irregularly between one and four times. Sixty-eight percent of the flocks showed little or no feather damage, 24% showed moderate damage and 8% showed severe damage. The feather score was better if the hens used the free-range area more intensely, the laying percentage at 60 weeks was higher, and if they were allowed to go outside sooner after arrival on the laying farm. In 69% of the flocks, hens had peck wounds in the vent area: on average this was 18% of the hens. Keel bone deformations were found in all flocks, on average in 21% of the birds. In 78% of the flocks, an average of 13% of the hens

  13. Health and Welfare in Dutch Organic Laying Hens.

    Science.gov (United States)

    Bestman, Monique; Wagenaar, Jan-Paul

    2014-06-20

    From 2007-2008, data on animal health and welfare and farm management during rearing and laying periods were collected from 49 flocks of organic laying hens in the Netherlands. Our aim was to investigate how organic egg farms performed in terms of animal health and welfare and which farm factors affected this performance. The flocks in our study were kept on farms with 34 to 25,000 hens (average 9,300 hens). Seventy-one percent of the flocks consisted of 'silver hybrids': white hens that lay brown eggs. Fifty-five percent of the flocks were kept in floor-based housing and 45% of the flocks in aviaries. No relation was found between the amount of time spent outdoors during the laying period and mortality at 60 weeks. Flocks that used their outdoor run more intensively had better feather scores. In 40% of the flocks there was mortality caused by predators. The average feed intake was 129 g/day at 30 weeks and 133 g/day at 60 weeks of age. The average percentage of mislaid eggs decreased from three at 30 weeks to two at 60 weeks. The average mortality was 7.8% at 60 weeks. Twenty-five percent of the flocks were not treated for worms in their first 50 weeks. Flubenol(©) was applied to the flocks that were treated. Ten percent of the flocks followed Flubenol(©) instructions for use and were wormed five or more times. The other 65% percent were treated irregularly between one and four times. Sixty-eight percent of the flocks showed little or no feather damage, 24% showed moderate damage and 8% showed severe damage. The feather score was better if the hens used the free-range area more intensely, the laying percentage at 60 weeks was higher, and if they were allowed to go outside sooner after arrival on the laying farm. In 69% of the flocks, hens had peck wounds in the vent area: on average this was 18% of the hens. Keel bone deformations were found in all flocks, on average in 21% of the birds. In 78% of the flocks, an average of 13% of the hens had foot-sole wounds

  14. Mature Turkey Breeder Hens Exposed to Pandemic Influenza H1N1: Resultant Effects on Morbidity, Mortality, and Fecundity.

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    Evans, Robert; Bommineni, Yugendar; Falk, Jonathan; Blackway, Adam; Young, Brent; Isenhart, Connie

    2015-03-01

    During the artificial insemination process, turkey breeder hens may become infected with influenza virus acquired from humans. The virus has been shown, through experimental infection, to localize in the reproductive tract, with limited dissemination in other tissues. A limited number of hens were used during these studies, and the overall flock morbidity, mortality, and fecundity were not able to be determined. The current case follows the progression of clinical signs in a flock of commercial breeder hens from onset of egg production losses in one house through the subsequent drops in four remaining houses. Each house contained approximately 3000 hens and followed a sequential loss of shell quality, reduced numbers of eggs, and fertility, while mild clinical signs were observed and mortality was slightly increased in a house with concurrent fowl cholera (Pasturella multocida) infection.

  15. Preliminary Report: Analysis of the baseline study on the prevalence of Salmonella in laying hen flocks of Gallus gallus

    DEFF Research Database (Denmark)

    Hald, Tine

    This is a preliminary report on the analysis of the Community-wide baseline study to estimate the prevalence of Salmonella in laying hen flocks. It is being published pending the full analysis of the entire dataset from the baseline study. The report contains the elements necessary for the establ......This is a preliminary report on the analysis of the Community-wide baseline study to estimate the prevalence of Salmonella in laying hen flocks. It is being published pending the full analysis of the entire dataset from the baseline study. The report contains the elements necessary...

  16. Performance of commercial laying hen genotypes on free range and organic farms in Switzerland, France and The Netherlands.

    Science.gov (United States)

    Leenstra, F; Maurer, V; Bestman, M; van Sambeek, F; Zeltner, E; Reuvekamp, B; Galea, F; van Niekerk, T

    2012-01-01

    1. A total of 257 farmers with free ranging laying hens (organic and conventional) in Switzerland, France and The Netherlands with 273 flocks were interviewed to determine the relationships between the genotype of the hens, management conditions and performance. 2. Almost 20 different genotypes (brands) were present on the farms. In France, all birds were brown feathered hens laying brown eggs. In Switzerland and The Netherlands, there were brown, white (white feathered hens laying white eggs) and silver (white feathered hens laying brown eggs) hens. In Switzerland, mixed flocks were also present. 3. The overall effect of system (organic vs. conventional free range) on egg production and mortality was significant, with higher mortality and lower egg production among organic hens. In pair wise comparisons within country, the difference was highly significant in The Netherlands, and showed a non-significant tendency in the same direction in Switzerland and France. 4. White hens tended to perform better than brown hens. Silver hens appeared to have a higher mortality and lower production per hen housed at 60 weeks of age. 5. There were no significant relationships between production, mortality, feather condition and use of outside run or with flock size. 6. There was more variation in mortality and egg production among farms with a small flock size than among farms with a large flock size.

  17. Egg production and egg quality in free-range laying hens housed at different outdoor stocking densities.

    Science.gov (United States)

    Campbell, D L M; Lee, C; Hinch, G N; Roberts, J R

    2017-09-01

    Free-range laying hen systems are increasing in number within Australia. Variation in outdoor stocking densities has led to development of a national information standard on free-range egg labeling, including setting a maximum density of 10,000 hens per hectare. However, there are few data on the impacts of differing outdoor densities on production and egg quality. ISA Brown hens in small (150 hens) flocks were housed in identical indoor pens, each with access (from 21 weeks) to different sized ranges simulating one of three outdoor stocking densities (2 replicates each: 2,000 hens/hectare (ha), 10,000 hens/ha, 20,000 hens/ha). Hen-day production was tracked from 21 through 35 weeks with eggs visually graded daily for external deformities. All eggs laid on one day were weighed each week. Eggs were collected from each pen at 25, 30, and 36 weeks and analyzed for egg quality. There were no effects of outdoor stocking density on average hen-day percentage production (P = 0.67), egg weight (P = 0.09), percentages of deformed eggs (P = 0.30), shell reflectivity (P = 0.74), shell breaking strength (P = 0.07), shell deformation (P = 0.83), or shell thickness (P = 0.24). Eggs from hens in the highest density had the highest percentage shell weight (P = 0.004) and eggs from the lowest density had the highest yolk color score (P egg quality is warranted. © 2017 Poultry Science Association Inc.

  18. Housing system and laying hen strain impacts on egg microbiology.

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    Jones, D R; Anderson, K E

    2013-08-01

    Alternative hen housing is becoming more commonplace in the egg market. However, a complete understanding of the implications for alternative housing systems on egg safety has not been achieved. The current study examines the impact of housing Hy-Line Brown, Hy-Line Silver Brown, and Barred Plymouth Rock hens in conventional cage, cage-free, and free range egg production systems on shell microbiology. Eggs were collected at 4 sampling periods. Egg shell emulsion pools were formed and enumerated for total aerobic organisms, Enterobacteriaceae, and yeast and mold counts. Hy-Line Brown and Hy-Line Silver Brown hens produced eggs with significantly (P Eggs from conventional cages had significantly different (P eggs with significantly different (P eggs having the lowest level of contamination for the hen strains. There were no differences within each strain among housing systems for yeast and mold contamination. The study shows that hen strain has an effect on egg microbial levels for various housing systems, and egg safety should be considered when making hen strain selections for each housing system.

  19. Mallard Use of Hen HousesTM in Eastern Ontario

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    J. Ryan Zimmerling

    2006-06-01

    Full Text Available Nesting structures for ground-nesting waterfowl may be an effective technique for increasing nesting success in regions in which nest success is below the 15% threshold needed to maintain a stable population. We studied the occupancy rate of artificial nesting structures called hen housesTM by Mallards (Anas platyrhynchos nesting in two different wetland habitats, beaver ponds and sewage lagoons, in eastern Ontario during 1999-2001. We hypothesized that, because natural cover was sparse on sewage lagoons, Mallards would occupy hen houses at a higher rate on sewage lagoons than on beaver ponds. However, of the 248 hen houses distributed between beaver ponds and sewage lagoons, none was occupied by waterfowl. Common Grackles (Quiscalus quiscula were the only avian species that nested in hen houses. However, Mallards successfully nested directly under several structures (n = 6 when water levels were low enough to expose the ground beneath them. Mayfield daily nest survival estimates for Mallards nesting in natural cover were similar on sewage lagoons and beaver ponds for all years (mean = 0.99 and were higher than most published estimates. Factors such as nesting cover, predation pressures, and structure design and material may influence the use of artificial hen houses and should be considered when planning a hen house program outside of the Prairie Pothole Region.

  20. Temporal changes in distribution, prevalence and intensity of northern fowl mite (Ornithonyssus sylviarum) parasitism in commercial caged laying hens, with a comprehensive economic analysis of parasite impact.

    Science.gov (United States)

    Mullens, Bradley A; Owen, Jeb P; Kuney, Douglas R; Szijj, Coralie E; Klingler, Kimberly A

    2009-03-09

    Establishment and spread of Ornithonyssus sylviarum were documented through time on sentinel hens (50 per house of 28,000-30,000 hens) in the first egg production cycle of three large commercial flocks (12 houses) of white leghorn hens. Mites were controlled using acaricide, and the impacts of treatment on mite populations and economic performance were documented. Mite prevalence and intensity increased rapidly and in tandem for 4-8 weeks after infestation. Intensity declined due to immune system involvement, but prevalence remained high, and this would affect mite sampling plan use and development. Early treatment was more effective at controlling mites; 85% of light infestations were eliminated by a pesticide spray (Ravap), versus 24% of heavy infestations. Hens infested later developed lower peak mite intensities, and those mite populations declined more quickly than on hens infested earlier in life. Raw spatial association by distance indices (SADIE), incorporating both the intensity and distribution of mites within a house, were high from week-to-week within a hen house. Once adjusted spatially to reflect variable hen cohorts becoming infested asynchronously, this analysis showed the association index tended to rebound at intervals of 5-6 weeks after the hen immune system first suppressed them. Large, consistent mite differences in one flock (high vs. low infestation levels) showed the economic damage of mite parasitism (assessed by flock indexing) was very high in the initial stages of mite expansion. Unmitigated infestations overall reduced egg production (2.1-4.0%), individual egg weights (0.5-2.2%), and feed conversion efficiency (5.7%), causing a profit reduction of $0.07-0.10 per hen for a 10-week period. Asynchronous infestation patterns among pesticide-treated hens may have contributed to a lack of apparent flock-level economic effects later in the production cycle. Individual egg weights differed with mite loads periodically, but could be either

  1. Development of a model forecasting Dermanyssus gallinae's population dynamics for advancing Integrated Pest Management in laying hen facilities.

    Science.gov (United States)

    Mul, Monique F; van Riel, Johan W; Roy, Lise; Zoons, Johan; André, Geert; George, David R; Meerburg, Bastiaan G; Dicke, Marcel; van Mourik, Simon; Groot Koerkamp, Peter W G

    2017-10-15

    The poultry red mite, Dermanyssus gallinae, is the most significant pest of egg laying hens in many parts of the world. Control of D. gallinae could be greatly improved with advanced Integrated Pest Management (IPM) for D. gallinae in laying hen facilities. The development of a model forecasting the pests' population dynamics in laying hen facilities without and post-treatment will contribute to this advanced IPM and could consequently improve implementation of IPM by farmers. The current work describes the development and demonstration of a model which can follow and forecast the population dynamics of D. gallinae in laying hen facilities given the variation of the population growth of D. gallinae within and between flocks. This high variation could partly be explained by house temperature, flock age, treatment, and hen house. The total population growth variation within and between flocks, however, was in part explained by temporal variation. For a substantial part this variation was unexplained. A dynamic adaptive model (DAP) was consequently developed, as models of this type are able to handle such temporal variations. The developed DAP model can forecast the population dynamics of D. gallinae, requiring only current flock population monitoring data, temperature data and information of the dates of any D. gallinae treatment. Importantly, the DAP model forecasted treatment effects, while compensating for location and time specific interactions, handling the variability of these parameters. The characteristics of this DAP model, and its compatibility with different mite monitoring methods, represent progression from existing approaches for forecasting D. gallinae that could contribute to advancing improved Integrated Pest Management (IPM) for D. gallinae in laying hen facilities. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Outdoor stocking density in free-range laying hens: radio-frequency identification of impacts on range use.

    Science.gov (United States)

    Campbell, D L M; Hinch, G N; Dyall, T R; Warin, L; Little, B A; Lee, C

    2017-01-01

    The number and size of free-range laying hen (Gallus gallus domesticus) production systems are increasing within Australia in response to consumer demand for perceived improvement in hen welfare. However, variation in outdoor stocking density has generated consumer dissatisfaction leading to the development of a national information standard on free-range egg labelling by the Australian Consumer Affairs Ministers. The current Australian Model Code of Practice for Domestic Poultry states a guideline of 1500 hens/ha, but no maximum density is set. Radio-frequency identification (RFID) tracking technology was used to measure daily range usage by individual ISA Brown hens housed in six small flocks (150 hens/flock - 50% of hens tagged), each with access to one of three outdoor stocking density treatments (two replicates per treatment: 2000, 10 000, 20 000 hens/ha), from 22 to 26, 27 to 31 and 32 to 36 weeks of age. There was some variation in range usage across the sampling periods and by weeks 32 to 36 individual hens from the lowest stocking density on average used the range for longer each day (Prange with 2% of tagged hens in each treatment never venturing outdoors and a large proportion that accessed the range daily (2000 hens/ha: 80.5%; 10 000 hens/ha: 66.5%; 20 000 hens/ha: 71.4%). On average, 38% to 48% of hens were seen on the range simultaneously and used all available areas of all ranges. These results of experimental-sized flocks have implications for determining optimal outdoor stocking densities for commercial free-range laying hens but further research would be needed to determine the effects of increased range usage on hen welfare.

  3. Risk factors associated with keel bone and foot pad disorders in laying hens housed in aviary systems

    NARCIS (Netherlands)

    Heerkens, J.L.T.; Delezie, E.; Rodenburg, T.B.; Kempen, I.; Zoons, J.; Ampe, B.; Tuyttens, F.A.M.

    2016-01-01

    Aviary systems for laying hens offer space and opportunities to perform natural behaviors. However, hen welfare can be impaired due to increased risk for keel bone and foot pad disorders in those systems. This cross-sectional study (N = 47 flocks) aimed to assess prevalences of keel bone and foot

  4. Ammonia emission from aviary housing systems for laying hens : inventory, characteristics and solutions

    NARCIS (Netherlands)

    Groot Koerkamp, P.W.G.

    1998-01-01

    The development and practical application of welfare friendly aviary housing systems for laying hens, that generally emit more ammonia per hen than battery cage housing systems, would conflict with the Dutch policy to substantially reduce the total emission of ammonia from animal

  5. Effect of light-emitting diode vs. fluorescent lighting on laying hens in aviary hen houses: Part 1 - Operational characteristics of lights and production traits of hens.

    Science.gov (United States)

    Long, H; Zhao, Y; Wang, T; Ning, Z; Xin, H

    2016-01-01

    Light-emitting diode (LED) lights are becoming more affordable for agricultural applications. Despite many lab-scale studies concerning impact of LED on poultry, little research has been documented under field production conditions, especially for laying hens. This 15-month field study was carried out to evaluate the effects of LED vs. fluorescent (FL) lights on laying hens (Dekalb white breed) using 4 (2 pairs) aviary hen houses each at a nominal capacity of 50,000 hens. The evaluation was done regarding operational characteristics of the lights and hen production traits. The results show that spatial distribution of the LED light was less uniform than that of the FL light. Light intensity of the LED light decreased by 27% after 3,360 h use but remained quite steady from 3,360 to 5,760 h use. Eleven out of 762 (1.44%) LED lamps (new at onset of the study) in the 2 houses failed during the 15-month experiment period. The neck area of the LED lamp was hottest, presumably the primary reason for the lamp failure as cracks were noticed in the neck region of all failed LED lamps. No differences were observed in egg weight, hen-day egg production, feed use, and mortality rate between LED and FL regimens. However, hens under the FL had higher eggs per hen housed and better feed conversion than those under the LED during 20 to 70 wk production (P Hens under the LED tended to have less feather uniformity and insulation than those under the FL (P hens under the LED showed a larger median avoidance distance than those under the FL at 36 wk age (P hens under the LED were more alert; but no difference at 60 wk age. More comparative research to quantify behavioral and production responses of different breeds of hens to LED vs. FL lighting seems warranted. © 2015 Poultry Science Association Inc.

  6. Gregarious nesting - An anti-predator response in laying hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch

    2012-01-01

    Gregarious nesting can be defined as a behaviour that occurs when a laying hen (Gallus gallus domesticus) given the choice between an occupied and an unoccupied nest site chooses the occupied nest site. It occurs frequently in flocks of laying hens kept under commercial conditions, contrasting...... the behaviour displayed by feral hens that isolate themselves from the flock during nesting activities. What motivates laying hens to perform gregarious nesting is unknown. One possibility is that gregarious nesting is an anti-predator response to the risk of nest predation emerging from behavioural flexibility...

  7. Effects of taurine and housing density on renal function in laying hens.

    Science.gov (United States)

    Ma, Zi-Li; Gao, Yang; Ma, Hai-Tian; Zheng, Liu-Hai; Dai, Bin; Miao, Jin-Feng; Zhang, Yuan-Shu

    This study investigated the putative protective effects of supplemental 2-aminoethane sulfonic acid (taurine) and reduced housing density on renal function in laying hens. We randomly assigned fifteen thousand green-shell laying hens into three groups: a free range group, a low-density caged group, and a high-density caged group. Each group was further divided equally into a control group (C) and a taurine treatment group (T). After 15 d, we analyzed histological changes in kidney cells, inflammatory mediator levels, oxidation and anti-oxidation levels. Experimental data revealed taurine supplementation, and rearing free range or in low-density housing can lessen morphological renal damage, inflammatory mediator levels, and oxidation levels and increase anti-oxidation levels. Our data demonstrate that taurine supplementation and a reduction in housing density can ameliorate renal impairment, increase productivity, enhance health, and promote welfare in laying hens.

  8. Influence of age and housing systems on properties of tibia and humerus of Lohmann White hens1: Bone properties of laying hens in commercial housing systems.

    Science.gov (United States)

    Regmi, P; Nelson, N; Haut, R C; Orth, M W; Karcher, D M

    2017-10-01

    This study was aimed at analyzing bone properties of Lohmann White hens in different commercial housing systems at various points throughout production. Pullets reared in conventional cages (CC) were either continued in CC or moved to enriched colony cages (EN) at 19 weeks. Pullets reared in cage-free aviaries (AV) were moved to AV hen houses. Bone samples were collected from 60 hens at each of 18 and 72 wk and 30 hens at 26 and 56 wk from each housing system. Left tibiae and humeri were broken under uniform bending to analyze mechanical properties. Cortical geometry was analyzed using digital calipers at the fracture site. Contralateral tibiae and humeri were used for measurement of ash percentage. AV pullets' humeri had 41% greater cortical areas, and tibiae had 19% greater cortical areas than the CC pullets (P < 0.05). Average humeri diameter was greater in AV pullets than in CC pullets (P < 0.05), whereas the tibiae outer dimensions were similar. Aviary pullet bones had greater stiffness (31 and 7% greater for tibiae and humeri, respectively) and second moment of inertia (43 and 13% greater for tibiae and humeri, respectively) than CC pullets (P < 0.05). The differences between bones of AV and CC hens persisted throughout the laying cycle. Moving CC pullets to EN resulted in decreased endosteal resorption in humeri, evident by a 7.5% greater cortical area in the EN hens (P < 0.05). Whole-bone breaking strength did not change with age. Stiffness increased with age, while energy to failure decreased in both the tibiae and humeri. These results indicated that tibiae and humeri of laying hens become stiffer but lose toughness and become brittle with age. Furthermore, AV and EN systems can bring positive changes in mechanical and structural properties that are more pronounced in the humerus than the tibia. © 2017 Poultry Science Association Inc.

  9. PARTICULATE MATTER CONCENTRATION AND EMISSION FACTOR IN THREE DIFFERENT LAYING HEN HOUSING SYSTEMS

    Directory of Open Access Journals (Sweden)

    Annamaria Costa

    2009-09-01

    Full Text Available The aim of this study was to evaluate PM10 concentration in three different laying hens houses (traditional battery cages with aerated open manure storage, aviary system and vertical tiered cages with manure belts with forced air drying and to evaluate particulate matter emission into atmosphere during one year of observation. Internal and external temperature and relative humidity, ventilation rate, PM10 concentration have been continuously monitored in order to evaluate particulate matter concentration changes during the day and the season and to define PM10 emission factors. PM10 concentration was corrected by gravimetric technique to lower measurements error. In the aviary system house, TSP and fine particulate matter (particles smaller than 2.5 micron concentration was measured. Average yearly PM10 concentration was remarkably higher in the aviary system house with 0.215 mg m-3 vs 108 mg m-3 for the ventilated belt house and vs 0.094 mg m-3 for the traditional battery cages house. In the Aviary system housing, TSP concentration was 0.444 mg m-3 and PM2.5 was 0.032 mg m-3, highlighting the existence of a severe working environment for men and animals. Recorded values for PM10 emission were 0.433 mg h-1 hen-1 for battery cages housing type, 0.081 mg h-1 hen-1 for ventilated belt cages house, values lower than those available in literature, while the aviary system housing type showed the highest PM10 emission (1.230 mg h-1 hen-1 with appreciable peaks during the morning, together with the increased animal activity and daily farmer operations, as feed administration, cleaning and droppings removal.

  10. House-level risk factors associated with the colonization of broiler flocks with Campylobacter spp. in Iceland, 2001 - 2004.

    Science.gov (United States)

    Guerin, Michele T; Martin, Wayne; Reiersen, Jarle; Berke, Olaf; McEwen, Scott A; Bisaillon, Jean-Robert; Lowman, Ruff

    2007-11-12

    The concurrent rise in consumption of fresh chicken meat and human campylobacteriosis in the late 1990's in Iceland led to a longitudinal study of the poultry industry to identify the means to decrease the frequency of broiler flock colonization with Campylobacter. Because horizontal transmission from the environment is thought to be the most likely source of Campylobacter to broilers, we aimed to identify broiler house characteristics and management practices associated with flock colonization. Between May 2001 and September 2004, pooled caecal samples were obtained from 1,425 flocks at slaughter and cultured for Campylobacter. Due to the strong seasonal variation in flock prevalence, analyses were restricted to a subset of 792 flocks raised during the four summer seasons. Logistic regression models with a farm random effect were used to analyse the association between flock Campylobacter status and house-level risk factors. A two-stage process was carried out. Variables were initially screened within major subsets: ventilation; roof and floor drainage; building quality, materials and repair; house structure; pest proofing; biosecurity; sanitation; and house size. Variables with p analyses were used in both the screening stage (i.e. within each subset) and in the comprehensive model. 217 out of 792 flocks (27.4%) tested positive. Four significant risk factors were identified. Campylobacter colonization was predicted to increase when the flock was raised in a house with vertical (OR = 2.7), or vertical and horizontal (OR = 3.2) ventilation shafts, when the producer's boots were cleaned and disinfected prior to entering the broiler house (OR = 2.2), and when the house was cleaned with geothermal water (OR = 3.3). The increased risk associated with vertical ventilation shafts might be related to the height of the vents and the potential for vectors such as flies to gain access to the house, or, increased difficulty in accessing the vents for proper cleaning and

  11. Bacteriological contamination, dirt, and cracks of eggshells in furnished cages and noncage systems for laying hens: an international on-farm comparison.

    Science.gov (United States)

    De Reu, K; Rodenburg, T B; Grijspeerdt, K; Messens, W; Heyndrickx, M; Tuyttens, F A M; Sonck, B; Zoons, J; Herman, L

    2009-11-01

    For laying hens, the effects of housing system on bacterial eggshell contamination and eggshell quality is almost exclusively studied in experimental hen houses. The aim of this study was to compare eggshell hygiene and quality under commercial conditions. Six flocks of laying hens in furnished cages and 7 flocks in noncage systems were visited when hens were about 60 wk of age. Farms from Belgium, the Netherlands, and Germany were included in the study. The following parameters were determined on eggs sampled at the egg belts: 1) bacterial eggshell contamination, as expressed by total count of aerobic bacteria and number of Enterobacteriaceae; 2) proportion of dirty eggs; and 3) proportion of cracked eggs and eggs with microcracks. Considerable within-flock differences were found in eggshell contamination with total count of aerobic bacteria, both for furnished cages (P < or = 0.001, range 4.24 to 5.22 log cfu/eggshell) and noncage systems (P < or = 0.001, range 4.35 to 5.51 log cfu/eggshell). On average, lower levels of contamination with total count of aerobic bacteria (4.75 vs. 4.98 log cfu/eggshell; P < or = 0.001) were found on eggshells from furnished cages compared with noncage systems. Concerning Enterobacteriaceae, no significant difference in average eggshell contamination between both systems could be shown. The total percentage of cracked eggs was higher (P < or = 0.01) in furnished cages (7.8%) compared with noncage systems (4.1%). This was, however, due to the high percentage of cracked eggs (24%) observed on one of the furnished cage farms. We conclude that bacteriological eggshell contamination and percentage of cracked eggs differed substantially between individual farms using the same housing system. This may also explain some discrepancies between the findings of the present study versus some findings of previous experimental studies or studies on a small number of farms. Although statistically significant, the average differences in

  12. Investigation of a type C/D botulism outbreak in free-range laying hens in France.

    Science.gov (United States)

    Souillard, R; Le Maréchal, C; Ballan, V; Rouxel, S; Léon, D; Balaine, L; Poëzevara, T; Houard, E; Robineau, B; Robinault, C; Chemaly, M; Le Bouquin, S

    2017-04-01

    In 2014, a botulism outbreak in a flock of laying hens was investigated in France. In the flock of 5020 hens, clinical signs of botulism occurred at 46 weeks of age. A type C/D botulism outbreak was confirmed using the mouse lethality assay for detection of botulinum toxin in serum and a real-time PCR test to detect Clostridium botulinum in intestinal contents. The disease lasted one week with a mortality rate of 2.6% without recurrence. Botulism in laying hens has rarely been reported. Five monthly visits were made to the farm between December 2014 and May 2015 for a longitudinal study of the persistence of C. botulinum in the poultry house after the outbreak, and to assess egg contamination by C. botulinum. Several samples were collected on each visit: in the house (from the ventilation circuit, the egg circuit, water and feed, droppings) and the surrounding area. Thirty clean and 30 dirty eggs were also swabbed at each visit. In addition, 12 dirty and 12 clean eggs were collected to analyse eggshell and egg content. The samples were analysed using real-time PCR to detect type C/D C. botulinum. The bacterium was still detected in the house more than 5 months after the outbreak, mostly on the walls and in the egg circuit. Regarding egg contamination, the bacteria were detected only on the shell but not in the content of the eggs. Control measures should therefore be implemented throughout the egg production period to avoid dissemination of the bacteria, particularly during egg collection.

  13. Specific characteristics of the aviary housing system affect plumage condition, mortality and production in laying hens

    NARCIS (Netherlands)

    Heerkens, J.L.T.; Delezie, Evelyne; Kempen, Ine; Zoons, Johan; Ampe, Bart; Rodenburg, T.B.; Tuyttens, F.A.M.

    2015-01-01

    Feather pecking and high mortality levels are significant welfare problems in non-cage housing systems for laying hens. The aim of this study was to identify husbandry-related risk factors for feather damage, mortality, and egg laying performance in laying hens housed in the multi-tier non-cage

  14. Relationship between welfare and individual ranging behaviour in commercial free-range laying hens.

    Science.gov (United States)

    Larsen, H; Hemsworth, P H; Cronin, G M; Gebhardt-Henrich, S G; Smith, C L; Rault, J-L

    2018-01-24

    Laying hens housed in free-range systems have access to an outdoor range, and individual hens within a flock differ in their ranging behaviour. Whether there is a link between ranging and laying hen welfare remains unclear. We analysed the relationships between ranging by individual hens on a commercial free-range layer farm and behavioural, physiological and health measures of animal welfare. We hypothesised that hens that access the range more will be (1) less fearful in general and in response to novelty and humans, (2) have better health in terms of physical body condition and (3) have a reduced physiological stress response to behavioural tests of fear and health assessments than hens that use the range less. Using radio frequency identification tracking across two flocks, we recorded individual hens' frequency, duration and consistency of ranging. We also assessed how far hens ventured into the range based on three zones: 0 to 2.4, 2.4 to 11.4 or >11.4 m from the shed. We assessed hen welfare using a variety of measures including: tonic immobility, open field, novel object, human approach, and human avoidance (HAV) behavioural tests; stress-induced plasma corticosterone response and faecal glucocorticoid metabolites; live weight, comb colour, and beak, plumage, footpad, and keel bone condition. Range use was positively correlated with plasma corticosterone response, faecal glucocorticoid metabolites, and greater flight distance during HAV. Hens that used the range more, moved towards rather than away from the novel object more often than hens that ranged less. Distance ranged from the shed was significantly associated with comb colour and beak condition, in that hens with darker combs and more intact beaks ranged further. Overall the findings suggest that there is no strong link between outdoor range usage and laying hen welfare. Alternatively, it may be that hens that differed in their ranging behaviour showed few differences in measures of welfare because

  15. House-level risk factors associated with the colonization of broiler flocks with Campylobacter spp. in Iceland, 2001 – 2004

    Directory of Open Access Journals (Sweden)

    Berke Olaf

    2007-11-01

    Full Text Available Abstract Background The concurrent rise in consumption of fresh chicken meat and human campylobacteriosis in the late 1990's in Iceland led to a longitudinal study of the poultry industry to identify the means to decrease the frequency of broiler flock colonization with Campylobacter. Because horizontal transmission from the environment is thought to be the most likely source of Campylobacter to broilers, we aimed to identify broiler house characteristics and management practices associated with flock colonization. Between May 2001 and September 2004, pooled caecal samples were obtained from 1,425 flocks at slaughter and cultured for Campylobacter. Due to the strong seasonal variation in flock prevalence, analyses were restricted to a subset of 792 flocks raised during the four summer seasons. Logistic regression models with a farm random effect were used to analyse the association between flock Campylobacter status and house-level risk factors. A two-stage process was carried out. Variables were initially screened within major subsets: ventilation; roof and floor drainage; building quality, materials and repair; house structure; pest proofing; biosecurity; sanitation; and house size. Variables with p ≤ 0.15 were then offered to a comprehensive model. Multivariable analyses were used in both the screening stage (i.e. within each subset and in the comprehensive model. Results 217 out of 792 flocks (27.4% tested positive. Four significant risk factors were identified. Campylobacter colonization was predicted to increase when the flock was raised in a house with vertical (OR = 2.7, or vertical and horizontal (OR = 3.2 ventilation shafts, when the producer's boots were cleaned and disinfected prior to entering the broiler house (OR = 2.2, and when the house was cleaned with geothermal water (OR = 3.3. Conclusion The increased risk associated with vertical ventilation shafts might be related to the height of the vents and the potential for vectors

  16. Detection of chicken anemia virus in the gonads and in the progeny of broiler breeder hens with high neutralizing antibody titers.

    Science.gov (United States)

    Brentano, L; Lazzarin, S; Bassi, S S; Klein, T A P; Schat, K A

    2005-01-05

    Previous evidence for the presence of chicken anemia virus (CAV) in the gonads of immune specific-pathogen-free chickens raised the question whether this occurs also in commercial breeders. The presence of CAV was investigated by nested PCR in the gonads and spleens of hens from two 55- and 59-week-old, CAV-vaccinated (flocks 2 and 3), and two 48- and 31-week-old non-vaccinated broiler breeder flocks (flocks 1 and 4). In addition, lymphoid tissues of 20-day-old embryos from these hens were also investigated for the presence of CAV. CAV was detected in the gonads and of 5/6 and 11/22 of the vaccinated hens and in some hens also in the spleen alone. Embryos from 7/8 and 5/18 of these hens were positive. In the non-vaccinated flocks, CAV was detected in the gonads of 11/34 and 10/10 hens in flocks 1 and 4, respectively. In addition, 11 birds in flock 1 had positive spleens. CAV DNA was detected in 3/11 and 2/10 of their embryos. CAV-positive gonads and embryos were detected in samples from hens with moderate as well as high VN antibody titers. Vaccinated chickens positive for CAV in the gonads and in their embryos had VN titers ranging from >1:512 to gonads of hens in commercial broiler breeder flocks even in the presence of high neutralizing antibody titers that have been associated with protection against CAV vertical transmission. It also suggests that transmission to the progeny may occur irrespectively of the level of the humoral immune response in the hens.

  17. Review of rearing-related factors affecting the welfare of laying hens

    Science.gov (United States)

    Janczak, Andrew M.; Riber, Anja B.

    2015-01-01

    Laying hens may face a number of welfare problems including: acute and chronic pain caused by beak trimming; exaggerated fearfulness that may cause stress and suffocation; difficulties in locating resources, resulting potentially in emaciation and dehydration; frustration and boredom, caused by an environment that is barren; feather pecking; cannibalism; foot lesions; and bone fractures. In Europe, a greater proportion of laying hens are housed in non-cage systems compared to the rest of the world. The extent of the different welfare problems may therefore vary between countries as the type of housing system influences the risk of suffering. More generally, many of these welfare problems are influenced by the rearing environment of the pullets. This article therefore focuses on welfare problems in laying hens that can be traced back to rearing. Factors that have been studied in relation to their effects on bird welfare include beak trimming, housing type, furnishing, enrichment, feeding, stocking density, flock size, sound and light levels, concentration of gasses, age at transfer from rearing to production facilities, similarity between rearing and production facilities, competence of staff, and interactions between bird strain and environment. The present review aims to summarize rearing-related risk factors of poor welfare in adult laying hens housed according to European Union legislation. It aims to identify gaps in current knowledge, and suggests strategies for improving bird welfare by improving rearing conditions. Two main conclusions of this work are that attempts should be made to use appropriate genetic material and that beak trimming should be limited where possible. In addition to this, the rearing system should provide constant access to appropriate substrates, perches, and mashed feed, and should be as similar as possible to the housing system used for the adult birds. Finally, young birds (pullets) should be moved to the production facilities before

  18. The effects of laying hen housing systems on egg safety and quality. In: Achieving sustainable production of eggs, Vol 1: Safety and Quality

    Science.gov (United States)

    Transitions in laying hen management and housing systems have constantly occurred throughout the history of commercial egg production. Around the world, there has been a rapid shift in hen housing requirements since the turn of the current century. In most cases, the changes in hen housing require...

  19. Laying hens in aviaries with different litter substrates: Behavior across the flock cycle and feather lipid content.

    Science.gov (United States)

    Campbell, D L M; Ali, A B A; Karcher, D M; Siegford, J M

    2017-09-01

    The tiered aviary for laying hens includes a floor litter area to promote foraging and dust bathing. Data are needed on hens' use of different litter substrates and effectiveness of substrates in removing excess feather lipids to ensure a suitable litter area. Bovans White hens were housed in commercial-style aviaries with access to one of 3 litter substrates (wood shavings, straw, or plastic turf mats-AstroTurf®, n = 4 aviary pens per substrate, 144 cage-reared hens populated per pen). Litter areas were videoed across 2 d each at 4 ages: immediately following first aviary opening (25 wk), then at 28, 50, and 68 weeks. Observations of hens throughout the d included percentages of all hens in each pen on the litter area, foraging and transitioning between the tiered enclosure and litter area. Percentages of hens dust bathing were observed from 11:00 to 15:00. Breast and back feather samples from 7 birds per pen at 28, 50, and 68 wk were analyzed for lipid content. Overall, fewer hens simultaneously accessed the AstroTurf® (P Feather lipid differences among litter substrates (P feathers (P nest boxes, but straw and shavings are more ideal litter substrates. Further study should investigate alternative substrates or regular substrate addition to encourage more foraging and dust bathing. © The Author 2017. Published by Oxford University Press on behalf of Poultry Science Association.

  20. Egg production and welfare of laying hens kept in different housing systems (conventional, enriched cage, and free range).

    Science.gov (United States)

    Yilmaz Dikmen, B; İpek, A; Şahan, Ü; Petek, M; Sözcü, A

    2016-07-01

    The aim of this study was to compare egg production performance and welfare traits of laying hens kept in conventional cage (CC), enriched cage (EC), and free range (FR). Lohmann Brown laying hens (n = 480 with 160 per housing type) were studied across a production cycle from placement at 17 wk until depopulation at 66 wk. The hens were randomly allocated into cages or pens of housing system groups; within each system there were four replicates with 40 hens in each pen or cage. The hen day egg production (P = 0.037), feed intake (FI) (P 0.05). The hens in the FR system had additional space for optimum comfort and better feather and bone traits, but the dirty egg ratio, feed consumption, and foot lesions were higher than in CC and EC systems. © 2016 Poultry Science Association Inc.

  1. Mixed housing of different genetic lines of laying hens negatively affects feather pecking and fear related behaviour

    NARCIS (Netherlands)

    Uitdehaag, K.A.; Rodenburg, T.B.; Bolhuis, J.E.; Decuypere, E.; Komen, J.

    2009-01-01

    Adult laying hens from Rhode Island Red (RIR) origin both express lower levels of feather pecking and lower fear responses towards a novel object than laying hens from White Leghorn (WL) origin. The present study investigated whether mixed housing of RIR and WL laying hens would affect their

  2. Effects of housing system on the costs of commercial egg production1

    Science.gov (United States)

    Matthews, W. A.; Sumner, D. A.

    2014-01-01

    This article reports the first publicly available egg production costs compared across 3 hen-housing systems. We collected detailed data from 2 flock cycles from a commercial egg farm operating a conventional barn, an aviary, and an enriched colony system at the same location. The farm employed the same operational and accounting procedures for each housing system. Results provide clear evidence that egg production costs are much higher for the aviary system than the other 2 housing systems. Feed costs per dozen eggs are somewhat higher for the aviary and lower for the enriched house compared with the conventional house. Labor costs are much lower for the conventional house than the other 2, and pullet costs are much higher for the aviary. Energy and miscellaneous costs are a minimal part of total operating costs and do not differ by housing system. Total capital investments per hen-capacity are much higher for the aviary and the enriched house. Capital costs per dozen eggs depend on assumptions about appropriate interest and depreciation rates. Using the same 10% rate for each housing system shows capital costs per dozen for the aviary and the enriched housing system are much higher than capital costs per dozen for the conventional house. The aviary has average operating costs (feed, labor, pullet, energy, and miscellaneous costs that recur for each flock and vary with egg production) about 23% higher and average total costs about 36% higher compared with the conventional house. The enriched housing system has average operating costs only about 4% higher compared with the conventional house, but average total costs are 13% higher than for the conventional house. PMID:25480736

  3. Radiographic examination of keel bone damage in living laying hens of different strains kept in two housing systems.

    Directory of Open Access Journals (Sweden)

    Beryl Katharina Eusemann

    Full Text Available A high prevalence of deviations and fractures of the keel bone is a widespread welfare problem in laying hens. The aim of this study was to experimentally investigate this multifactorial problem throughout the laying period and to compare the prevalence and severity in different layer lines and different housing systems. High performing white (WLA and brown (BLA pure bred layer lines and low performing white (R11, G11 and brown layer lines (L68 were kept in both single cages and a floor housing system. A total of 97 hens (19 or 20 from each line, respectively were repeatedly radiographed in the 35th, 51st and 72nd week of age. Fracture prevalence increased with age (p<0.001. The proportion of deviated keel bone area increased only for caged BLA, WLA and R11 hens (p<0.05 and was significantly higher for caged WLA and R11 hens compared to floor-housed WLA and R11 hens in the 72nd week of age (p<0.05. In the 72nd week of age hens in the floor housing system showed significantly more fractures than hens kept in cages (p<0.05. Prevalence of keel bone deviations was significantly higher in the white layer line R11 but significantly lower in the white layer line G11 compared to both brown layer lines and WLA (p<0.05. Brown layers showed significantly more fractures than white layers (p<0.05 in the 51st and 72nd week of age. Within the brown layers there was a significantly lower prevalence of deviations (p<0.05 and fractures (p<0.05 in the low performing (L68 compared to the high performing line (BLA. Our results show a different development of keel bone damage in caged compared to floor-housed hens under experimental conditions. Additionally, they indicate genetic effects on keel bone damage.

  4. Influence of different housing systems on the performance of hens of ...

    African Journals Online (AJOL)

    Overall the battery system seems to be more advantageous than the other systems, yielding a signifi- cantly higher henday egg ... formance of hens of four laying strains in a battery, floor house and ..... and disease resistance. 23-27 July, 1990.

  5. Occurrence of infectious laryngotracheitis outbreaks in commercial layer hens detected by ELISA.

    Science.gov (United States)

    Aras, Zeki; Yavuz, Orhan; Sanioğlu Gölen, Gökçenur

    2018-02-09

    Infectious laryngotracheitis (ILT) is an acute respiratory disease of chickens and a cause of great economic loss in commercial layers. The aims of this study were to investigate the prevalence of ILT in the field outbreaks and to compare the characteristics of ILT-infected and free flocks of commercial layers. A total of 625 blood serum samples were collected from 25 different layer flocks. The presence of antibodies against infectious laryngotracheitis virus (ILTV) in each sample was determined by ELISA. Of the 625 serum samples, 266 (42.56%) were found to be positive for ILTV antibodies. A total of 16 (64%) flocks were detected ILT positive by ELISA method. The mortality of infected flocks was statistically higher (P  0.05) than hens in free flocks. In conclusion, the results of this study indicated a high prevalence of ILT infection in the commercial layer flocks in Konya region, Turkey. In outbreaks, ILT significantly increased the mortality rate and decreased the average live weight in layer hens.

  6. Effects of housing system and age of laying hens on egg performance in fresh pasta production: pasta cooking behaviour.

    Science.gov (United States)

    Alamprese, Cristina; Casiraghi, Ernestina; Rossi, Margherita

    2011-03-30

    Very few studies concern the effects of layer housing systems and age on egg technological properties. Thus the aim of this work was to study the influence of these two factors on egg performance in fresh pasta production, focusing on pasta cooking behaviour. Samples of pasta subjected to analysis were prepared with eggs laid by Hy-Line Brown hens (from 27 to 68 weeks old) housed in cage, barn and organic systems. Higher average values of weight increase and matter loss during pasta cooking were observed for samples prepared with eggs laid by older hens. Such cooking behaviour indicated the development of a weaker pasta protein network, resulting from a decrease in the quantity of albumen protein and an increase in fat content, which is due to the reduction in albumen/yolk ratio during hen aging. The housing system had a significant effect only on matter loss in cooking water, but differences between samples were so small as to be unlikely perceived by consumers. Both hen age and housing system significantly affected pasta cooking behaviour, but the greatest effect was exerted by the hen age. Copyright © 2010 Society of Chemical Industry.

  7. Effects of housing system on the costs of commercial egg production.

    Science.gov (United States)

    Matthews, W A; Sumner, D A

    2015-03-01

    This article reports the first publicly available egg production costs compared across 3 hen-housing systems. We collected detailed data from 2 flock cycles from a commercial egg farm operating a conventional barn, an aviary, and an enriched colony system at the same location. The farm employed the same operational and accounting procedures for each housing system. Results provide clear evidence that egg production costs are much higher for the aviary system than the other 2 housing systems. Feed costs per dozen eggs are somewhat higher for the aviary and lower for the enriched house compared with the conventional house. Labor costs are much lower for the conventional house than the other 2, and pullet costs are much higher for the aviary. Energy and miscellaneous costs are a minimal part of total operating costs and do not differ by housing system. Total capital investments per hen-capacity are much higher for the aviary and the enriched house. Capital costs per dozen eggs depend on assumptions about appropriate interest and depreciation rates. Using the same 10% rate for each housing system shows capital costs per dozen for the aviary and the enriched housing system are much higher than capital costs per dozen for the conventional house. The aviary has average operating costs (feed, labor, pullet, energy, and miscellaneous costs that recur for each flock and vary with egg production) about 23% higher and average total costs about 36% higher compared with the conventional house. The enriched housing system has average operating costs only about 4% higher compared with the conventional house, but average total costs are 13% higher than for the conventional house. © The Author 2015. Published by Oxford University Press on behalf of Poultry Science Association.

  8. Hen genetic strain and extended cold storage influence on physical egg quality from cage-free aviary housing system.

    Science.gov (United States)

    Jones, D R; Karcher, D M; Regmi, P; Robison, C O; Gast, R K

    2018-04-02

    In the United States, there is an increase in need for cage-free eggs in retail and food manufacturing sectors. Understanding the impact of cage-free systems and the corresponding management on egg quality is pertinent as the U.S. industry adapts existing housing and builds new cage-free housing structures. A study was conducted comparing 2 brown shell and 2 white shell hen strains housed in a cage-free aviary system. Each set of eggs were placed in cold storage and assessed at 0, 2, 4, 8, and 12 wk. Eggs were collected at 21, 31, 42, and 60 wk of hen age. A full profile of physical quality measurements was conducted on up to 18 intact eggs for each hen strain/egg storage/hen age combination. Egg weight increased approximately 10 g for brown shell and 14 g for white shell eggs as hens aged. Many of the properties monitored were significantly impacted by all 3 main effects (hen strain, egg storage, and hen age) resulting in 3-way interactions. A brown and a white shell strain had stronger shells (44 N; P study also determined volume of shell, total length, maximum width, and percent length at maximum width to more accurately indicate egg shape than shape index. One brown shell strain produced eggs with the most consistent shape characteristics over the hen ages monitored. White shell eggs from the cage-free aviary housing produced the highest whole-egg total solids between 31 to 60 wk of hen age, whereas brown shell eggs resulted in the most consistent level of whole-egg total solids (22-23.5%). The brown and white shell strains in the current study produce cage-free aviary eggs with distinctive physical quality attributes. The outcomes from this study can be utilized by the U.S. egg industry in planning management strategies and market placement of cage-free eggs.

  9. Outdoor stocking density in free-range laying hens: effects on behaviour and welfare.

    Science.gov (United States)

    Campbell, D L M; Hinch, G N; Downing, J A; Lee, C

    2017-06-01

    Free-range laying hen systems are increasing within Australia and research is needed to determine optimal outdoor stocking densities. Six small (n=150 hens) experimental flocks of ISA Brown laying hens were housed with access to ranges simulating one of three outdoor stocking densities with two pen replicates per density: 2000 hens/ha, 10 000 hens/ha or 20 000 hens/ha. Birds were provided daily range access from 21 to 36 weeks of age and the range usage of 50% of hens was tracked using radio-frequency identification technology. Throughout the study, basic external health assessments following a modified version of the Welfare Quality® protocol showed most birds were in visibly good condition (although keel damage was increasingly present with age) with few differences between stocking densities. Toenail length at 36 weeks of age was negatively correlated with hours spent ranging for all pens of birds (all r⩾-0.23, P⩽0.04). At 23 weeks of age, there were no differences between outdoor stocking densities in albumen corticosterone concentrations (P=0.44). At 35 weeks of age, density effects were significant (Prange and indoors showed more dust bathing and foraging (scratching followed by ground-pecking) was performed outdoors, but more resting indoors (all Prange but the most resting outdoors, with hens from the 20 000 hens/ha densities showing the least amount of resting outdoors (all Pfree-range system management practices.

  10. Opportunities for exercise during pullet rearing, Part II: Long-term effects on bone characteristics of adult laying hens at the end-of-lay.

    Science.gov (United States)

    Casey-Trott, T M; Korver, D R; Guerin, M T; Sandilands, V; Torrey, S; Widowski, T M

    2017-08-01

    Osteoporosis in laying hens has been a production and welfare concern for several decades. The objective of this study was to determine whether differing opportunities for exercise during pullet rearing influences long-term bone quality characteristics in end-of-lay hens. A secondary objective was to assess whether differing opportunities for exercise in adult housing systems alters bone quality characteristics in end-of-lay hens. Four flock replicates of 588 Lohmann Selected Leghorn-Lite pullets were reared in either conventional cages (Conv) or an aviary rearing system (Avi) and placed into conventional cages (CC), 30-bird furnished cages (FC-S), or 60-bird furnished cages (FC-L) for adult housing. Wing and leg bones were collected at the end-of-lay to quantify bone composition and strength using quantitative computed tomography and bone breaking strength (BBS). At the end-of-lay, Avi hens had greater total and cortical cross-sectional area (P lay. © The Author 2017. Published by Oxford University Press on behalf of Poultry Science Association.

  11. Impact of feeder space on laying hen feeding behavior and production performance in enriched colony housing.

    Science.gov (United States)

    Oliveira, J L; Xin, H; Wu, H

    2018-05-30

    Current feeder space recommendations in laying hen welfare guidelines are inconsistent among and within countries. One determining criterion forming the recommendations (e.g. 12.0 cm/hen for the EU guideline) is that all birds can feed simultaneously. However, if there are other resources in the environment, as in enriched colony housing (ECH), it is unknown whether group-housed hens will choose to feed simultaneously. This study assesses the impact of feeder space on feeding behavior of 60 laying hens (W-36) in ECH using a ultra-high frequency radio-frequency identification-based tracking system. The feeder spaces investigated were 12.0, 9.5, 8.5 and 6.5 cm/hen, achieved by blocking portions of the overall feeder access to keep hens at the same stocking density. Each feeder space treatment, randomly assigned over the course of the experiment, lasted for 7 consecutive days. Feeding behaviors were characterized as daily time spent at the feeder (TS, min/hen-day), daily frequency of visits to the feeder (FV, #/hen-day), and maximum or average percentage of hens feeding simultaneously (MPB, APB, %). Group-average daily feed intake (FI, g/hen-day), water use (WU, g/hen-day), and hen-day egg production (HDEP, %) were also measured. The results revealed that at 12.0 cm/hen, where unoccupied feeder space was present, a maximum of 59.0±1.4% (average of 31.7±0.3%) hens fed simultaneously. No significant differences were detected among 12.0, 9.5 and 8.5 cm/hen in TS (293±10, 286±10 and 281±10 min/hen-day) and MPB (59.0±1.4, 57.3±1.4 and 53.3±1.4%) (P>0.05). The outcome of no significant differences also held true between 12.0 and 9.5 cm/hen in APB (31.7±0.3 v. 30.8±0.3%) and between 9.5 and 8.5 cm/hen in all response variables measured (P>0.05). However, there were significant differences in APB between 6.5 cm/hen and all other treatments; in TS and FV between 6.5 and 9.5 cm/hen; and in MPB between 6.5 and 12 cm/hen (P0.05). The results revealed that synchronous

  12. Measuring fearfulness of hens in commercial organic egg production

    DEFF Research Database (Denmark)

    Hegelund, Lene; Sørensen, Jan Tind

    2007-01-01

    To evaluate agreement between flock-based fear tests used in welfare assessments of laying hens in commercial organic farms, three tests were applied in 27 flocks of layers. Tests were performed at 35 and 55 weeks of age and were based on the concepts of 'novel object', 'sudden sound' and two dif...

  13. Egg fertility and hatchability in Avians broiler-breeder hens under ...

    African Journals Online (AJOL)

    Impact of temperature and humidity in different month of lay was evaluated on fertility and hatchability in broiler breeder hens reared in Sapele, Nigeria. Six million, six hundred and nineteen thousand, seven hundred and forty six eggs from flocks of Avians broiler-breeder hens reared between 2005 and 2006 in a farm ...

  14. Air Quality in Alternative Housing Systems may have an Impact on Laying Hen Welfare. Part II—Ammonia

    Directory of Open Access Journals (Sweden)

    Bruce David

    2015-09-01

    Full Text Available The EU ban on conventional barren cages for laying hens from 2012 has improved many aspects of laying hen welfare. The new housing systems allow for the expression of highly-motivated behaviors. However, the systems available for intensive large-scale egg production (e.g., aviaries, floor housing systems, furnished cages may cause other welfare challenges. We have reviewed the literature regarding the health, behavior, production characteristics, and welfare of laying hens when exposed to ammonia in their housing environment. Concentrations of ammonia gas are commonly high in aviaries and floor housing systems in which manure is not regularly removed, whereas they are usually lower in furnished cages. High levels are found during the cold season when ventilation flow is often reduced. Ammonia is a pungent gas, and behavioral studies indicate chickens are averse to the gas. High concentrations of gaseous ammonia can have adverse health effects and, when very high, even influence production performance. The most profound effects seen are the occurrence of lesions in the respiratory tract and keratoconjunctivitis. There is also evidence that high ammonia concentrations predispose poultry to respiratory disease and secondary infections. We conclude that there are animal welfare challenges related to high ammonia levels, and that immediate actions are needed. Development of improved systems and management routines for manure removal and ventilation will be important for the reduction of ammonia levels and hence will contribute to safeguarding hen welfare.

  15. Raman spectroscopic analysis of the carotenoid concentration in egg yolks depending on the feeding and housing conditions of the laying hens.

    Science.gov (United States)

    Hesterberg, Karoline; Schanzer, Sabine; Patzelt, Alexa; Sterry, Wolfram; Fluhr, Joachim W; Meinke, Martina C; Lademann, Jürgen; Darvin, Maxim E

    2012-01-01

    Resonance Raman spectroscopic measurements are suited to analyze the concentration of carotenoid antioxidants in biological samples. Previously, it has been shown that the carotenoid concentration of nutritional egg yolks has a direct influence on the carotenoid content of human skin in vivo. In the present study, resonance Raman spectroscopy was used to analyze the carotenoid concentration in the yolks of hen eggs, which were housed in battery cages or alternatively on free-range grassland. The egg yolks of hens, which had access to grassland, contained approximately double the amount of carotenoid concentration than the egg yolks of hens housed in battery cages (p egg yolks, depending on fodder, housing and weather conditions, were investigated. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Demographics and practices of semi-intensive free-range farming systems in Australia with an outdoor stocking density of ≤1500 hens/hectare

    Science.gov (United States)

    Ruhnke, Isabelle; de Koning, Carolyn; Drake, Kelly; Skerman, Alan G.; Hinch, Geoff N.; Glatz, Philip C.

    2017-01-01

    Baseline information on demographics and practices on semi-intensive free-range egg farms with an outdoor stocking density of ≤1500 hens/hectare in Australia is presented. Free-range egg production is changing the structure of the egg industry in Australia and a broad variety and tiers of free-range systems have emerged due to lack of concrete legislative standards on outdoor stocking densities in the past. Information was extracted from a pre-existing online free-range poultry survey dataset, consisting of a total of 79 questions related to nutrition, pasture management, welfare and health, animal housing, environmental impact and economics. Forty-one free-range egg farms, with an outdoor stocking density of ≤1500 hens/hectare, were identified in the dataset from all major Australian states. Two types of semi-intensive free-range housing systems were documented: mobile (modified caravan/trailer) housing (56%), and fixed sheds (44%). Seventy-two percent of respondents reported >75% of the hens in the flock used the outdoor range. All respondents reported ingestion of range components by hens in the form of vegetation, insects, stones and grit. Up to 10% mortality was reported by 40% respondents with predation (34%), cannibalism (29%), heat stress (24%) and grass impaction (19.5%) as major causes. Biosecurity on farms was sub-optimal with 8 of the 10 actions implemented by farms. Applied research and communication of results to farmers is highly recommended to ensure optimum health and welfare of free-range laying hens and sustained egg production. PMID:29065169

  17. Air Quality in Alternative Housing Systems May Have an Impact on Laying Hen Welfare. Part I—Dust

    Directory of Open Access Journals (Sweden)

    Bruce David

    2015-07-01

    Full Text Available The new legislation for laying hens in the European Union put a ban on conventional cages. Production systems must now provide the hens with access to a nest, a perch, and material for dust bathing. These requirements will improve the behavioral aspects of animal welfare. However, when hens are kept with access to litter, it is a concern that polluted air may become an increased threat to health and therefore also a welfare problem. This article reviews the literature regarding the health and welfare effects birds experience when exposed to barn dust. Dust is composed of inorganic and organic compounds, from the birds themselves as well as from feed, litter, and building materials. Dust may be a vector for microorganisms and toxins. In general, studies indicate that housing systems where laying hens have access to litter as aviaries and floor systems consistently have higher concentrations of suspended dust than caged hens with little (furnished cages or no access to litter (conventional cages. The higher dust levels in aviaries and floor housing are also caused by increased bird activity in the non-cage systems. There are gaps in both the basic and applied knowledge of how birds react to dust and aerosol contaminants, i.e., what levels they find aversive and/or impair health. Nevertheless, high dust levels may compromise the health and welfare of both birds and their caretakers and the poor air quality often found in new poultry housing systems needs to be addressed. It is necessary to develop prophylactic measures and to refine the production systems in order to achieve the full welfare benefits of the cage ban.

  18. Ranging Behaviour of Commercial Free-Range Laying Hens.

    Science.gov (United States)

    Chielo, Leonard Ikenna; Pike, Tom; Cooper, Jonathan

    2016-04-26

    In this study, the range use and behaviour of laying hens in commercial free-range flocks was explored. Six flocks were each visited on four separate days and data collected from their outdoor area (divided into zones based on distance from shed and available resources). These were: apron (0-10 m from shed normally without cover or other enrichments); enriched belt (10-50 m from shed where resources such as manmade cover, saplings and dust baths were provided); and outer range (beyond 50 m from shed with no cover and mainly grass pasture). Data collection consisted of counting the number of hens in each zone and recording behaviour, feather condition and nearest neighbour distance (NND) of 20 birds per zone on each visit day. In addition, we used techniques derived from ecological surveys to establish four transects perpendicular to the shed, running through the apron, enriched belt and outer range. Number of hens in each 10 m × 10 m quadrat was recorded four times per day as was the temperature and relative humidity of the outer range. On average, 12.5% of hens were found outside. Of these, 5.4% were found in the apron; 4.3% in the enriched zone; and 2.8% were in the outer range. This pattern was supported by data from quadrats, where the density of hens sharply dropped with increasing distance from shed. Consequently, NND was greatest in the outer range, least in the apron and intermediate in the enriched belt. Hens sampled in outer range and enriched belts had better feather condition than those from the apron. Standing, ground pecking, walking and foraging were the most commonly recorded activities with standing and pecking most likely to occur in the apron, and walking and foraging more common in the outer range. Use of the outer range declined with lower temperatures and increasing relative humidity, though use of apron and enriched belt was not affected by variation in these measures. These data support previous findings that outer range areas tend to be

  19. Effect of space allowance and cage size on laying hens housed in furnished cages, Part I: Performance and well-being

    Science.gov (United States)

    Widowski, T. M; Caston, L. J; Hunniford, M. E; Cooley, L; Torrey, S

    2017-01-01

    Abstract There are few published data on the effects of housing laying hens at different densities in large furnished cages (FC; a.k.a. enriched colony cages). The objective of this study was to determine the effects of housing laying hens at 2 space allowances (SA) in 2 sizes of FC on measures of production and well-being. At 18 wk of age, 1,218 LSL-Lite hens were housed in cages furnished with a curtained nesting area, perches, and scratch mat, and stocked at either 520 cm2 (Low) or 748 cm2 (High) total floor space. This resulted in 4 group sizes: 40 vs. 28 birds in smaller FC (SFC) and 80 vs. 55 in larger FC (LFC). Data were collected from 20 to 72 wks of age. There was no effect of cage size (P = 0.21) or SA (P = 0.37) on hen day egg production, egg weight (PSize = 0.90; PSA = 0.73), or eggshell deformation (PSize = 0.14; PSA = 0.053), but feed disappearance was higher in SFC than LFC (P = 0.005). Mortality to 72 wk was not affected by cage size (P = 0.78) or SA (P = 0.55). BW (P = 0.006) and BW CV (P = 0.008) increased with age but were not affected by treatment. Feather cleanliness was poorer in FC with low SA vs. high (P hens housed at the lower space allowance may be compromised according to some welfare assessment criteria. PMID:29050408

  20. Demographics and practices of semi-intensive free-range farming systems in Australia with an outdoor stocking density of ≤1500 hens/hectare.

    Science.gov (United States)

    Singh, Mini; Ruhnke, Isabelle; de Koning, Carolyn; Drake, Kelly; Skerman, Alan G; Hinch, Geoff N; Glatz, Philip C

    2017-01-01

    Baseline information on demographics and practices on semi-intensive free-range egg farms with an outdoor stocking density of ≤1500 hens/hectare in Australia is presented. Free-range egg production is changing the structure of the egg industry in Australia and a broad variety and tiers of free-range systems have emerged due to lack of concrete legislative standards on outdoor stocking densities in the past. Information was extracted from a pre-existing online free-range poultry survey dataset, consisting of a total of 79 questions related to nutrition, pasture management, welfare and health, animal housing, environmental impact and economics. Forty-one free-range egg farms, with an outdoor stocking density of ≤1500 hens/hectare, were identified in the dataset from all major Australian states. Two types of semi-intensive free-range housing systems were documented: mobile (modified caravan/trailer) housing (56%), and fixed sheds (44%). Seventy-two percent of respondents reported >75% of the hens in the flock used the outdoor range. All respondents reported ingestion of range components by hens in the form of vegetation, insects, stones and grit. Up to 10% mortality was reported by 40% respondents with predation (34%), cannibalism (29%), heat stress (24%) and grass impaction (19.5%) as major causes. Biosecurity on farms was sub-optimal with 8 of the 10 actions implemented by free-range egg production. This study resulted in identification of current practices and key challenges on semi-intensive free-range egg farms. Applied research and communication of results to farmers is highly recommended to ensure optimum health and welfare of free-range laying hens and sustained egg production.

  1. Access to litter during rearing and environmental enrichment during production reduce fearfulness in adult laying hens

    DEFF Research Database (Denmark)

    Brantsaeter, Margrethe; Tahamtani, Fernanda M.; Nordgreen, Janicke

    2017-01-01

    Exaggerated fear-reactions are associated with injurious flying, smothering, feather pecking and other events that compromise animal welfare in laying hens. The aim of this study was to test the hypothesis that chicks with access to litter during the first five weeks of life would be less fearful...... as adult hens compared to birds reared without access to litter. The hypothesis was tested in a national on-farm study in commercial aviary flocks in Norway. Five rearing farmers divided the pullets into two groups within their rearing houses. While the chicks were enclosed inside the aviary rows during...... reared with paper) were visited. During the visit, the fearfulness of the adult birds was tested in a stationary person test and a novel object test. The data was analysed by ANOVA or logistic regression as appropriate. The access to litter during rearing did not influence the number of birds...

  2. Effects of ambient temperature, feather cover, and housing system on energy partitioning and performance in laying hens

    NARCIS (Netherlands)

    Krimpen, van M.M.; Binnendijk, G.P.; Anker, van den I.; Heetkamp, M.J.W.; Kwakkel, R.P.; Brand, van den H.

    2014-01-01

    Environmental factors, such as ambient temperature (T), feather cover (FC), and housing system (HS), probably affect energy requirements of laying hens. Using a 3 × 2 × 2 factorial arrangement, interaction effects of T (11, 16, and 21°C), FC (100 and 50%), and HS (cage and floor housing) on energy

  3. Ranging Behaviour of Commercial Free-Range Laying Hens

    Directory of Open Access Journals (Sweden)

    Leonard Ikenna Chielo

    2016-04-01

    Full Text Available In this study, the range use and behaviour of laying hens in commercial free-range flocks was explored. Six flocks were each visited on four separate days and data collected from their outdoor area (divided into zones based on distance from shed and available resources. These were: apron (0–10 m from shed normally without cover or other enrichments; enriched belt (10–50 m from shed where resources such as manmade cover, saplings and dust baths were provided; and outer range (beyond 50 m from shed with no cover and mainly grass pasture. Data collection consisted of counting the number of hens in each zone and recording behaviour, feather condition and nearest neighbour distance (NND of 20 birds per zone on each visit day. In addition, we used techniques derived from ecological surveys to establish four transects perpendicular to the shed, running through the apron, enriched belt and outer range. Number of hens in each 10 m × 10 m quadrat was recorded four times per day as was the temperature and relative humidity of the outer range. On average, 12.5% of hens were found outside. Of these, 5.4% were found in the apron; 4.3% in the enriched zone; and 2.8% were in the outer range. This pattern was supported by data from quadrats, where the density of hens sharply dropped with increasing distance from shed. Consequently, NND was greatest in the outer range, least in the apron and intermediate in the enriched belt. Hens sampled in outer range and enriched belts had better feather condition than those from the apron. Standing, ground pecking, walking and foraging were the most commonly recorded activities with standing and pecking most likely to occur in the apron, and walking and foraging more common in the outer range. Use of the outer range declined with lower temperatures and increasing relative humidity, though use of apron and enriched belt was not affected by variation in these measures. These data support previous findings that outer range

  4. Prevalence and magnitude of helminth infections in organic laying hens (Gallus gallus domesticus) across Europe

    DEFF Research Database (Denmark)

    Thapa, Sundar; Hinrichsen, Lena Karina; Brenninkmeyer, Christine

    2015-01-01

    Helminths are associated with health- and welfare problems in organic laying hens. The present observational cross-sectional study therefore aimed to estimate the prevalence and worm burdens of intestinal helminths in organic flocks of laying hens in 8 European countries, and to identify manageme...

  5. Demographics and practices of semi-intensive free-range farming systems in Australia with an outdoor stocking density of ≤1500 hens/hectare.

    Directory of Open Access Journals (Sweden)

    Mini Singh

    Full Text Available Baseline information on demographics and practices on semi-intensive free-range egg farms with an outdoor stocking density of ≤1500 hens/hectare in Australia is presented. Free-range egg production is changing the structure of the egg industry in Australia and a broad variety and tiers of free-range systems have emerged due to lack of concrete legislative standards on outdoor stocking densities in the past. Information was extracted from a pre-existing online free-range poultry survey dataset, consisting of a total of 79 questions related to nutrition, pasture management, welfare and health, animal housing, environmental impact and economics. Forty-one free-range egg farms, with an outdoor stocking density of ≤1500 hens/hectare, were identified in the dataset from all major Australian states. Two types of semi-intensive free-range housing systems were documented: mobile (modified caravan/trailer housing (56%, and fixed sheds (44%. Seventy-two percent of respondents reported >75% of the hens in the flock used the outdoor range. All respondents reported ingestion of range components by hens in the form of vegetation, insects, stones and grit. Up to 10% mortality was reported by 40% respondents with predation (34%, cannibalism (29%, heat stress (24% and grass impaction (19.5% as major causes. Biosecurity on farms was sub-optimal with 8 of the 10 actions implemented by <50% respondents. Customer demand, consumer sentiment and welfare were the major factors for farmers moving into free-range egg production. This study resulted in identification of current practices and key challenges on semi-intensive free-range egg farms. Applied research and communication of results to farmers is highly recommended to ensure optimum health and welfare of free-range laying hens and sustained egg production.

  6. Performance of commercial laying hen genotypes on free range and organic farms in Switzerland, France and The Netherlands

    NARCIS (Netherlands)

    Leenstra, F.R.; Maurer, V.; Bestman, M.W.P.; Sambeek van, F.; Zeltner, E.; Reuvekamp, B.F.J.; Galea, F.; Niekerk, van T.G.C.M.

    2012-01-01

    1. A total of 257 farmers with free ranging laying hens (organic and conventional) in Switzerland, France and The Netherlands with 273 flocks were interviewed to determine the relationships between the genotype of the hens, management conditions and performance. 2. Almost 20 different genotypes

  7. Review of rearing-related factors affecting the welfare of laying hens

    DEFF Research Database (Denmark)

    Janczak, Andrew M.; Riber, Anja Brinch

    2015-01-01

    Laying hens may face a number of welfare problems including: acute and chronic pain caused by beak trimming; exaggerated fearfulness that may cause stress and suffocation; difficulties in locating resources, resulting potentially in emaciation and dehydration; frustration and boredom, caused...... to their effects on bird welfare include beak trimming, housing type, furnishing, enrichment, feeding, stocking density, flock size, sound and light levels, concentration of gasses, age at transfer from rearing to production facilities, similarity between rearing and production facilities, competence of staff...... rearing conditions. Two main conclusions of this work are that attempts should be made to use appropriate genetic material and that beak trimming should be limited where possible. In addition to this, the rearing system should provide constant access to appropriate substrates, perches, and mashed feed...

  8. Reductive Effect of Fly Screens on the Campylobacter Prevalence of Broiler Flocks in Summer

    DEFF Research Database (Denmark)

    Hald, B.; Sommer, Helle Mølgaard; Skovgård, H. S.

    Flies act as vectors in the introduction of Campylobacter from the environment to broiler flocks. We conducted a case-control study to evaluate the effect of fly screens on the prevalence of Campylobacter in broiler flocks. Cases were 52 broiler flocks reared in 20 houses on 11 farms between June...... and November 2006, where houses were equipped with fly screens made of glass fibre mesh. The controls consisted of 70 broiler flocks reared in 25 matched houses on 13 farms without screens. Other bio-security and management routines were strictly as before the study. All broiler houses were ventilated through...... wall inlets and roof outlets. The broiler flocks were sampled at days 21, 28, and 35 and at slaughter (on day 35 to 42). Samples were tested for Campylobacter by PCR. Campylobacter prevalence data were analyzed using SAS (SAS Institute). In fly screened houses, the Campylobacter prevalence was 15.4% (8...

  9. Development of a prognostic tool for the occurrence of feather pecking and cannibalism in laying hens.

    Science.gov (United States)

    Kaesberg, A-K U; Louton, H; Erhard, M; Schmidt, P; Zepp, M; Helmer, F; Schwarzer, A

    2018-03-01

    In July 2015, a German voluntary decree stipulated that the keeping of beak-trimmed laying hens after the 1st of January 2017 will no longer be permitted. Simultaneously, the present project was initiated to validate a newly developed prognostic tool for laying hen farmers to forecast, at the beginning of a laying period, the probability of future problems with feather pecking and cannibalism in their flock. For this purpose, we used a computer-based prognostic tool in form of a questionnaire that was easy and quick to complete and facilitated comparisons of different flocks. It contained various possible risk factors that were classified into 3 score categories (1 = "no need for action," 2 = "intermediate need for action," 3 = "instant need for action"). For the validation of this tool, 43 flocks of 41 farms were examined twice, at the beginning of the laying period (around the 20th wk of life) and around the 67th wk of life. At both visits, the designated investigators filled out the questionnaire and assessed the plumage condition and the skin lesions (as indicators of occurrence of feather pecking and cannibalism) of 50 laying hens of each flock. The average prognostic score of the first visit was compared with the existence of feather pecking and cannibalism in each flock at the end of the laying period. The results showed that the prognostic score was negatively correlated with the plumage score (r = -0.32; 95% confidence interval [CI]: [-0.56; -0.02]) and positively correlated with the skin lesion score (r = 0.38; 95% CI: [0.09; 0.61]). These relationships demonstrate that a better prognostic score was associated with a better plumage and skin lesion score. After performing a principal component analysis on the single scores, we found that only 6 components are sufficient to obtain highly sensitive and specific prognostic results. Thus, the data of this analysis should be used for creating applicable software for use on laying hen farms.

  10. The GroupHouseNet COST Action: exploiting European synergy to reduce feather pecking in laying hens

    DEFF Research Database (Denmark)

    Rodenburg, T.B.; Berk, J; Dimitrov, I.

    2017-01-01

    The COST Action GroupHouseNet focuses on the reduction of damaging behaviour in laying hens and pigs, benefiting from the fact that there are many similarities in causation and solutions for feather pecking and tail biting. The research in the network focuses on three main topics, addressed by th...

  11. Comparison of Bioactive Compound Content in Egg Yolk Oil Extracted from Eggs Obtained from Different Laying Hen Housing Systems

    OpenAIRE

    Aleksandrs Kovalcuks

    2015-01-01

    Egg yolk oil is a natural source of bioactive compounds such as unsaturated fatty acids, oil soluble vitamins, pigments and others. Bioactive compound content in egg yolk oil depends from its content in eggs, from which oil was extracted. Many studies show that bioactive compound content in egg is correlated to the content of these compounds in hen feed, but there is also an opinion that hen housing systems also have influence on egg chemical content. The aim of this stud...

  12. Effect of housing arrangement on fecal-oral transmission of avian hepatitis E virus in chicken flocks.

    Science.gov (United States)

    Liu, Baoyuan; Sun, Yani; Chen, Yiyang; Du, Taofeng; Nan, Yuchen; Wang, Xinjie; Li, Huixia; Huang, Baicheng; Zhang, Gaiping; Zhou, En-Min; Zhao, Qin

    2017-09-07

    Avian hepatitis E virus (HEV) infection is common in chicken flocks in China, as currently no measures exist to prevent the spread of the disease. In this study, we analyzed the effect of caged versus cage-free housing arrangements on avian HEV transmission. First, 127 serum and 110 clinical fecal samples were collected from 4 chicken flocks including the two arrangements in Shaanxi Province, China and tested for HEV antibodies and/or virus. Concurrently, 36 specific-pathogen-free chickens were divided equally into four experimental living arrangement groups, designated cage-free (Inoculated), caged (Inoculated), cage-free (Negative) and caged (Negative) groups. In caged groups, three cages contained 3 chickens each. Three chickens each from cage-free (Inoculated) and caged (Inoculated) groups (one chicken of each cage) were inoculated by cutaneous ulnar vein with the same dose of avian HEV, respectively. The cage-free (Negative) and caged (Negative) groups served as negative control. Serum and fecal samples were collected at 1 to 7 weeks post-inoculation (wpi) and liver lesions were scored at 7 wpi. The results of serology showed that the avian HEV infection rate (54.10%) of the cage-free chickens was significantly higher than the one (12.12%) for caged chickens (P chickens (6) was significantly higher than the one for the uninoculated caged birds (2), as evidenced by seroconversion, fecal virus shedding, viremia and gross and microscopic liver lesions. These results suggest that reduction of contact with feces as seen in the caged arrangement of housing chickens can reduce avian HEV transmission. This study provides insights for prevention and control of avian HEV infection in chicken flocks.

  13. The effect of clomiphene-citrate on broody turkey hens.

    Science.gov (United States)

    Robinzon, B; Shafir, Z; Perek, M; Snapir, N

    1984-11-01

    The effect of clomiphene-citrate (CC) on broody turkey hens was examined in three experiments. Turkey hens were categorized as broody if found in the laying nest during 6 successive checks per day, if they were reluctant to leave the nest for a period of 24 hr or more, if they had ruffled feathers, and if their cloacal orifices were contracted so as to prevent vaginal exposure by abdominal massage during artificial insemination. In each experiment, 20 hens, selected as broody from commercial breeding flocks, were treated; half were treated with CC at a dosage of 6 mg/kg body weight/day (per os) for 5 consecutive days, and the rest (control) received parallel treatment with a placebo (CaCO3). In all experiments, the CC administration alleviated brooding behavior and increased egg production.

  14. Effect of perches on liver health of hens.

    Science.gov (United States)

    Jiang, S; Hester, P Y; Hu, J Y; Yan, F F; Dennis, R L; Cheng, H W

    2014-07-01

    Fatty liver is a common energy metabolic disorder in caged laying hens. Considering that the egg industry is shifting from conventional cages to alternative housing systems such as enriched cages, the objective of this study was to determine the effects of perches on fat deposition and liver health in laying hens. Three hundred twenty-four 17-wk-old White Leghorn hens were housed in 1 of 4 treatments with 9 hens per cage. Treatment 1 hens never had access to perches during their life cycle. Treatment 2 hens had access to perches during the pullet phase only. Treatment 3 hens had access to perches during the laying phase only. Treatment 4 hens always had access to perches. Liver weight, abdominal fat pad weight, BW, liver fat, and circulating alanine transaminase, aspartate transaminase, and adiponectin were determined. Provision of perches during either the rearing or laying phase did not affect liver health in 71-wk-old hens. However, perch access compared with no perch access during the egg laying phase reduced relative fat pad weight. These results suggest that providing perches as a means of stimulating activity reduced abdominal fat deposition in caged hens during the laying period. However, perch access in caged hens was ineffective in reducing fat deposition in the liver and altering enzyme activities related to improved liver function. © 2014 Poultry Science Association Inc.

  15. Epidemiologic characterization of Colorado backyard bird flocks.

    Science.gov (United States)

    Smith, Emily I; Reif, John S; Hill, Ashley E; Slota, Katharine E; Miller, Ryan S; Bjork, Kathe E; Pabilonia, Kristy L

    2012-06-01

    Backyard gallinaceous bird flocks may play an important role in the spread of infectious diseases within poultry populations as well as the transmission of zoonotic diseases to humans. An epidemiologic characterization was conducted of Colorado backyard flocks to gather information on general flock characteristics, human movement of birds, human-bird interaction, biosecurity practices, and flock health. Our results suggest that backyard poultry flocks in Colorado are small-sized flocks (68.6% of flocks had meat or egg) production for the family (86.44%) or as pet or hobby birds (42.27%). The backyard flock environment may promote bird-to-bird transmission as well as bird-to-human transmission of infectious disease. Birds are primarily housed with free access to the outside (96.85%), and many are moved from the home premises (46.06% within 1 yr). Human contact with backyard flocks is high, biosecurity practices are minimal, and bird health is negatively impacted by increased movement events. Increased knowledge of backyard bird characteristics and associated management practices can provide guidelines for the development of measures to decrease disease transmission between bird populations, decrease disease transmission from birds to humans, and increase the overall health of backyard birds.

  16. EFFECT OF AGE AND BODY WEIGHT AT MOLTING ON THE PERFORMANCE OF BROILER BREEDER HENS UNDER ENVIRONMENTAL CONTROL HOUSES IN PAKISTAN

    Directory of Open Access Journals (Sweden)

    HASSAN M. MALIK, EHSAN-UL-HAQ AND F. AHMAD

    2008-12-01

    Full Text Available In the present study, 2700 broiler breeder hens of Arbor Acre strain were divided into 27 experimental units (100 each and allotted to nine treatments randomly having three replications each. The birds were kept under uniform managemental conditions throughout the experimental period of 32 weeks post molt period. The birds were molted under conventional method at 50, 55 and 60 weeks of age having three different body weights i.e. 3000, 3500 and 4000 ± 50g under 3x3 factorial design. At the time of 5% production, data on production performance (weekly eggs/hen, hen day production, body weight and feed consumption were recorded. Data collected was analyzed by analysis of variance technique under 3x3 factorial arrangement of treatment and the differences among the treatment means were analyzed by Duncan’s Multiple Range test. Significant (P<0.05 differences due to body weight and age were noted for feed consumption, weekly eggs per hen, hen day production and hen house production. Broiler breeders having low age group (50 weeks and medium body weight (3500g resulted in maximum production performance/net profit.

  17. Internal roosting location is associated with differential use of the outdoor range by free-range laying hens.

    Science.gov (United States)

    Pettersson, I C; Weeks, C A; Norman, K I; Knowles, T G; Nicol, C J

    2018-04-01

    1. In commercial free-range systems for laying hens, popholes to the outdoor range are often installed on one side of the house only. In multi-tier systems, it is possible that some individuals fail to access the range due to internal barriers to movement. 2. Five commercial multi-tier flocks from different units were studied. For each flock, two different colour markers were used to distinguish 200 birds roosting near the popholes (NP-Roost) and 200 birds roosting far from the popholes (FP-Roost) at night. The following day, counts of marked birds on the range and inside the house were performed. 3. Significantly more NP-Roost birds were observed in all areas of the outdoor range than FP-Roost birds the next day. Distance of FP area from the popholes was very strongly positively correlated with effect size in the adjacent range area. 4. Additionally, in the indoor area far from the popholes (FP) more FP-Roost birds were observed the next day than NP-Roost birds. In the indoor area near to the popholes (NP) more NP-Roost birds were observed the next day than FP-Roost birds. 5. These results suggest that roosting location is associated with differential range use when popholes are only available on one side of the shed as birds that roosted far from the popholes used the range less.

  18. Bacterial contamination of eggs and behaviour of poultry flocks in the free range environment.

    Science.gov (United States)

    Moyle, Talia; Drake, Kelly; Gole, Vaibhav; Chousalkar, Kapil; Hazel, Susan

    2016-12-01

    The free range production system is becoming more common in Australia and is expected to increase. Free range hens are exposed to more stressors in comparison to hens from barn and cage systems and it is suggested that stress can increase bacterial shedding on eggs. The aims of this study were to examine the level of total bacteria and Enterobacteriaceae populations, as well as the presence of Salmonella and Campylobacter, in eggs collected from two free range flocks on two different farms and to conduct longitudinal observations of the behaviour and welfare of hens in the free range production system. Hen age (weeks) was shown to have a significant effect (increase) on the level of total bacteria on the egg shell surface and in shell pores, as well as having an effect on feather condition score. As the hens aged, the frequency of external visual egg characteristics increased, as did feather condition score (where feather condition was poorer). These observations indicate areas which should be investigated further to improve the food safety of eggs and optimise the welfare of free range hens. Crown Copyright © 2016. Published by Elsevier Ltd. All rights reserved.

  19. Dietary methionine requirement of Jing Brown layer hens from 9 to 17 weeks of age.

    Science.gov (United States)

    Meng, G H; Song, D; Li, L B; Yang, C J; Qu, Z X; Gao, Y P

    2017-10-01

    This study was conducted to evaluate the effect of dietary methionine (Met) supplementation in growth performance and reproductive performance of Jing Brown layer hens. A total of 375 9-week-old Jing Brown layer hens were allocated equally to five treatments consisting of 5 replicates with 15 hens. Hens were fed with a diet of corn and soya bean meal supplemented with 0.23%, 0.27%, 0.31%, 0.35% and 0.39% Met respectively. Different Met levels did not significantly affect average daily feed intake (ADFI), average daily gain (ADG) and feed/gain ratio (F/G) (p > 0.05), whereas flock uniformity (FU) and jejunum index were significantly different (p hens from 9 to 17 weeks old is 0.29%. Journal of Animal Physiology and Animal Nutrition © 2016 Blackwell Verlag GmbH.

  20. Analysis of factors important for the occurrence of Campylobacter in Danish broiler flocks

    DEFF Research Database (Denmark)

    Sommer, Helle Mølgaard; Heuer, Ole Eske; Sørensen, Anna Irene Vedel

    2013-01-01

    a multivariate analysis including all 43 variables. A multivariate analysis was conducted using a generalized linear model, and the correlations between the houses from the same farms were accounted for by adding a variance structure to the model. The procedures for analyses included backward elimination...... of positive flocks/total number of flocks delivered over the 2-year period).The following factors were found to be significantly associated with the occurrence of Campylobacter in the broiler flocks: old broiler houses, late introduction of whole wheat in the feed, relatively high broiler age at slaughter...

  1. Flies and Campylobacter infection of broiler flocks

    DEFF Research Database (Denmark)

    Hald, Birthe; Skovgård, Henrik; Bang, Dang Duong

    2004-01-01

    A total of 8.2% of flies caught outside a broiler house in Denmark had the potential to transmit Campylobacter jejuni to chickens, and hundreds of flies per day passed through the ventilation system into the broiler house. Our study suggests that flies may be an important source of Campylobacter ...... infection of broiler flocks in summer....

  2. Comparative study of housing conditions in turkey flocks and the influence of the results in the meat inspection

    OpenAIRE

    Hultsch, Nadja

    2010-01-01

    According to Chapter 1 oft the GlHV, dated December 3rd , 1997 feedlots of Poultry fattening are required to collect Data from the housing conditions of the animals. Taking these fattening data into consideration during official veterinarian Examinations is designed to getting the best possible Information about the flock. Results of the ante mortem examination are to be examined or explained by its origination, to be able to determine the general health condition of a herd. Thi...

  3. Ghrelin plasma concentration does not covary with energy demand in adult laying hens.

    Science.gov (United States)

    Höhne, A; Schrader, L; Weigend, S; Petow, S

    2017-10-01

    The peptide hormone ghrelin is suggested to be involved in food intake regulation in young growing chicken. Whether ghrelin is involved in the regulation of energetic balance associated with laying performance in adult laying hens was studied by use of 4 chicken lines that differ in laying performance and phylogeny (4 lines; 16 hens per line). As housing conditions are also known to affect energy demand, half of the hens per line were housed in single cages and the other half of hens were maintained in a floor housing system. Plasma samples were collected at 17 to 19, 33 to 35, 49 to 51, and 72 wk of age and analyzed with a chicken ghrelin ELISA Kit. From caged hens, individual food consumption and laying performance additionally was recorded. Due to its function in growth and its relationship with ghrelin, also GH plasma concentrations were analyzed. Ghrelin concentrations did not differ between the 4 lines at any of the test periods (all P > 0.05). Ghrelin was negatively related to food consumption only in the growing period of the high-performing lines (both P ghrelin concentrations compared with caged hens (P ghrelin is not involved in regulating energy intake related to laying performance but rather seems to be related to body growth and housing condition before start of lay, the latter possibly due to differences in hens' behavioral activity. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Risk factors for Campylobacter spp. infection in Senegalese broiler-chicken flocks.

    Science.gov (United States)

    Cardinale, E; Tall, F; Guèye, E F; Cisse, M; Salvat, G

    2004-06-10

    Our objective was to identify the risk factors for Campylobacter infection in Senegalese broiler flocks. Seventy broiler farms were studied around Dakar from January 2000 to December 2001 around Dakar. A questionnaire was administered to the farmers, and samples of fresh droppings were taken to assess the flocks' Campylobacter status. About 63% of the flocks were infected by Campylobacter spp.; Campylobacter jejuni was the most-prevalent species (P hatchery to the farm as feed plates (rather than specifically designed feed plates). Alternatively, thorough cleaning and disinfection of poultry-house surroundings and manure disposal outside the farm were associated with decreased flock risk.

  5. Feather eating and its associations with plumage damage and feathers on the floor in commercial farms of laying hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch; Hinrichsen, Lena Karina

    2016-01-01

    Feather eating has been associated with feather pecking, which continues to pose economic and welfare problems in egg production. Knowledge on feather eating is limited and studies of feather eating in commercial flocks of laying hens have not been performed previously. Therefore, the main...... objective was to investigate feather eating and its association with plumage damage and floor feather characteristics in commercial flocks of layers in barn and organic production systems. The study was performed in 13 flocks of barn layers and 17 flocks of organic layers. Each flock was visited at around.......3% in organic; P=0.99). Our hypothesis about a positive correlation between feather eating and plumage damage was not supported as no correlation was found between the prevalence of poor plumage condition and the prevalence of droppings with feather content. However, the prevalence of pecking damaged floor...

  6. Behaviour of laying hens in two types of aviary systems on 25 commercial farms in Sweden.

    Science.gov (United States)

    Odén, K; Keeling, L J; Algers, B

    2002-05-01

    1. Fifty-one flocks of laying hens in two high-density loose-housing systems were studied on 25 commercial farms in Sweden as part of a government test programme for evaluating new systems for laying hens. Six different hybrids were used in group sizes ranging from 250 to 5 000 birds. Stocking-densities varied from 10.2 to 19.1 birds per m2 floor area. No birds were beak trimmed. 2. The distribution of birds in the system, the frequency and location of aggressive pecks and feather pecks, the dust bathing activity and the birds' fear reaction to the keeper and to a novel object were measured. Direct behaviour observations were carried out twice per flock, at weeks 35 and 55. 3. The proportion of birds at the different locations was relatively constant across the 8-h observation period in the tiered system, but changed over time in the perch system, which may reflect a difference in access to resources between the systems. At night the top perches/tiers were preferred although when stocking-density increased, other sites were also used. 4. Aggression occurred mainly on the litter or in the nest areas. It did not differ between hybrids, but increased with age in the tiered system. Feather pecks occurred mainly on the litter. Brown hybrids feather pecked more than white ones, while white hybrids reacted more both to the keeper and to a novel object than did the brown hybrids. 5. It was concluded that access to nests was insufficient in both systems, as was litter space. Feed space was insufficient in the tiered system if food requirements increased. Design of the top perches, in the perch system, should be improved to allow birds to perch high up in the system without blocking access to feed etc. for others.

  7. Prevalence of Listeria monocytogenes in poultry production in France.

    Science.gov (United States)

    Chemaly, Marianne; Toquin, Marie-Therese; Le Nôtre, Yolene; Fravalo, Philippe

    2008-10-01

    This study aimed to update and create a data set from laying hens and broilers regarding contamination by Listeria monocytogenes. Two hundred laying-hen flocks were sampled, with 88 flocks reared in cages and 112 reared on the floor. One hundred forty-five broiler flocks were sampled, with 85 conventional and 60 free-range flocks. A total of 774 and 725 samples were analyzed from laying hens and broilers, respectively. L. monocytogenes was detected in 31 of 200 flocks, yielding an estimated prevalence of 15.5% in laying-hen flocks. Among positive flocks, there appeared a significant (P = 0.004) difference between caged and floor-reared hens, with a higher detection in dust samples from floor-reared hens. In positive caged hen flocks, significant (P = 0.028) differences between dust and fecal samples appeared, with a higher detection in feces than in dust samples. In broiler flocks, L. monocytogenes was isolated in 46 of 145 flocks, yielding an estimated prevalence of 32% (28% in conventional flocks versus 37% in the free-range flocks). L. monocytogenes was isolated in samples taken from conventional flocks with a lower frequency than in free-range flocks (13 versus 18%, respectively). The serotyping of L. monocytogenes strains showed that the majority belonged to type 1/2a in laying-hen flocks (74.3%) and in broiler flocks (40.5%). A significant difference (P = 0.007) between laying hens and broilers was shown for serogroup 4 and for serovar 1/2b (P = 0.007); these serogroups were more prevalent in broilers (40%) than in laying hens (5.7%).

  8. Assessment of welfare and egg production of laying hens moravia ssl in small-scale breeding

    Directory of Open Access Journals (Sweden)

    Mária Angelovičová

    2015-10-01

    Full Text Available The purpose of this study was to investigate the welfare of laying hens Moravia SSL housed in small-scale hen house with free range, behavior, egg production and selected physical indicators of eggs and chemical indicators of egg mass. The laying hens were kept in a hen house on deep litter. Breeding facility of hen house was within the meaning of recommendation for applying the principles of welfare, i.e. the space and breeding facility within the meaning of enriched breeding environment. Stocking density of the laying hens corresponded with recommendations for unrestricted movement and implementing natural activities. The hen house was equipped with the perch, nest, feeder and drinker. The commercial feed mixture was used for feeding, which is intended for laying hens. The kitchen remains were added to feed mixture, as are wet bread, the non-edible remains of foodstuffs. A feed mixture was served to laying hens 825 g per day. The laying hens had free access to drinking water, grazing, ground pecking, ground scratching and dust-bathing and in the free range. We focused investigation of on the egg laying intensity, selected parameters of physical egg quality and chemical egg contents. Time to relax of laying hens was adjusted according to the summer and winter breeding seasons. The main activities of free-range hens are grazing, ground pecking, ground scratching and dust-bathing. The main activities of free-range hens are grazing, ground pecking, ground scratching and dust-bathing. These activities were investigated in laying hens too in dependent of year period, more in the summer. Housing of the hens was equipped with the perch. The laying hens regularly used a perch. A beginning of occupation the perch was at the time of time growing dark, at the end of the light day. A nesting material was selected regular, monthly exchange. It was meadow hay of excellent quality for the collection of high quality and safe eggs from nests in the hen house

  9. Antimicrobial susceptibility of Brachyspira spp. isolated from commercial laying hens and free-living wild mallards (Anas platyrhynchos).

    Science.gov (United States)

    Jansson, Désirée S; Pringle, Märit

    2011-08-01

    In vitro antimicrobial susceptibility to tylosin, valnemulin, tiamulin, doxycycline, lincomycin and ampicillin was investigated by broth dilution in 48 Brachyspira spp. isolates from commercial laying hens (n=30) and free-living wild mallards (Anas platyrhynchos) (n=18). Presumed pathogens (Brachyspira alvinipulli, Brachyspira intermedia, Brachyspira pilosicoli), commensals (Brachyspira murdochii, Brachyspira innocens, "Brachyspira pulli"), and isolates of undetermined species affiliation were included. The laying hens had not been exposed to therapeutic levels of antimicrobials for at least 50 weeks before sampling, and low levels of environmental antimicrobial exposure were presumed in mallards. No isolates with decreased susceptibility to tylosin, valnemulin, tiamulin or doxycycline were found. Decreased susceptibility to lincomycin (minimum inhibitory concentration 16 µg/ml) was detected in two isolates (Brachyspira sp.) from laying hens. Five isolates showed decreased susceptibility to ampicillin (minimum inhibitory concentration 16 to >32 µg/ml), including two "B. pulli" and one B. alvinipulli from laying hens, and isolates of B. pilosicoli and "B. pulli" from mallards. Decreased susceptibility to ampicillin was associated with β-lactamase activity in four isolates. A new variant of a class D β-lactamase gene designated bla (oxa-192) was identified in a B. pilosicoli isolate of mallard origin. This is the first time the genetic basis for antimicrobial resistance is described in Brachyspira spp. from a free-living wild bird. Isolates displaying decreased susceptibility to ampicillin were accompanied by fully susceptible isolates of the same species or other genotypes within three laying hen flocks. This underlines the need for performing antimicrobial susceptibility tests on single clones/genotypes, and to analyse multiple isolates from the same flock.

  10. Mineral content of eggs differs with hens strain, age and rearing environment

    Science.gov (United States)

    Egg nutrient quality is strongly influenced by hen diet but is also affected by rearing environment, hen strain and hen age. The objective of the current study was to determine the effect of: 1) conventional battery cages 2) enrichable cage systems 3) enriched colony housing 4) cage free and 5) free...

  11. A retrospective study on salmonella infection in Danish broiler flocks

    DEFF Research Database (Denmark)

    Angen, Øystein; Skov, M. N.; Chriél, Mariann

    1996-01-01

    -year period from 1992 to 1993 in Denmark. The AM database contains information collected by the ante-mortem veterinarians, from the slaughterhouses, and from the salmonella examinations carried out at the National Veterinary Laboratory. The epidemiological unit was the individual broiler flock....... The salmonella status of the flock was determined by examining the caecal tonsils from 16 3-week-old chickens from each flock. This procedure would detect a salmonella-infected flock, with a probability above 95%, if the prevalence is above 20%. Furthermore, the structure and quality of the collected data have...... been evaluated. Fourteen variables were selected for analysis by multivariable logistic regression. An increased risk of salmonella infection in the broiler Becks was associated with the biggest hatcheries and feedmill, with an increasing number of houses on the farm, if the preceding flock...

  12. Welfare Consequences of Omitting Beak Trimming in Barn Layers

    DEFF Research Database (Denmark)

    Riber, Anja Brinch; Hinrichsen, Lena Karina

    2017-01-01

    Beak trimming is used worldwide as a method of reducing the damage to feathers and skin caused by injurious pecking in laying hens. However, beak trimming also causes some welfare issues as trimming the beak results in pain and sensory loss. Due to this dilemma, there is an ongoing discussion...... in several European countries about whether to ban beak trimming. In this study, we investigated the welfare consequences of keeping layers with intact beaks and examined for links between injurious pecking damage and keel bone damage on an individual level. A study was conducted on 10 commercial farms...... housing laying hens in the barn system. Each farm participated with a flock of beak-trimmed hens (T) and a flock of non-trimmed (NT) hens that were visited around 32 and 62 weeks of age. During visits, the condition of plumage, skin, feet, and keel bone of 100 hens was assessed. Mortality was recorded...

  13. Medullary bone and humeral breaking strength in laying hens

    International Nuclear Information System (INIS)

    Fleming, R.H.; McCormack, H.A.; McTeir, L.; Whitehead, C.C.

    1998-01-01

    To test the hypothesis that large amounts of medullary bone in the humeral diaphysis may increase breaking strength, various parameters of bone quality and quantity were examined in two large flocks of hens near end of lay. We conclude that the amount of medullary bone in the humerus of hens during the laying period influences bone strength. This medullary bone may not have any intrinsic strength, but may act by contributing to the fracture resistance of the surrounding cortical bone. Using a quantitative, low dose, radiographic technique, we can predict, from early in the laying period, those birds which will develop large amounts of medullary bone in their humeri by the end of the laying period. The formation of medullary bone in the humeral diaphysis is not at the expense of the surrounding radiographed cortical bone

  14. Smothering in UK free-range flocks. Part 2: investigating correlations between disease, housing and management practices.

    Science.gov (United States)

    Rayner, A C; Gill, R; Brass, D; Willings, T H; Bright, A

    2016-09-10

    Smothering, when birds group together in a way that results in death from suffocation, is a welfare and economic concern for the egg industry. This questionnaire-based study explored correlations between disease, housing, management practices and smothering on free-range farms. A binomial logistic regression approach was used to test whether question responses predicted occurrence of nest box smothers (NBS) and panic and recurring smothers (PSRS) on farms. Breed (P=0.008) and nest box manufacturer (P=0.014) predicted NBS. Breed and nest box design have been previously reported to affect nesting behaviour. The affect of nest box manufacturer found in this study may illustrate the effect of nest box design features or house layouts. Nest box manufacturer (P=0.009), feeding oyster grit or grain on the litter (Prange use on a sunny day (Pranging) may contribute to smothering, whereas some management practices such as those aimed at occupying birds may be beneficial, illustrating the delicate balance of factors involved in free-range egg production. It is hoped that these results will stimulate further work exploring the suitability of housing design and management of laying hens in light of smothering. British Veterinary Association.

  15. Feather eating and its associations with plumage damage and feathers on the floor in commercial farms of laying hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch; Hinrichsen, Lena Karina

    2016-01-01

    Feather eating has been associated with feather pecking, which continues to pose economic and welfare problems in egg production. Knowledge on feather eating is limited and studies of feather eating in commercial flocks of laying hens have not been performed previously. Therefore, the main object...

  16. Prevalence and risk factors for Salmonella spp. and Campylobacter spp. caecal colonization in broiler chicken and turkey flocks slaughtered in Quebec, Canada.

    Science.gov (United States)

    Arsenault, Julie; Letellier, Ann; Quessy, Sylvain; Normand, Valérie; Boulianne, Martine

    2007-10-16

    We conducted an observational study to estimate prevalence and risk factors for Salmonella spp. and Campylobacter spp. caecal colonization in poultry. Eighty-one broiler chicken and 59 turkey flocks selected among flocks slaughtered in the province of Quebec, Canada, were included in the study. Flock status was evaluated by culturing pooled caecal contents from about 30 birds per flock. Exposure to potential risk factors was evaluated with a questionnaire. Odds ratios were computed using multivariable logistic regression. The prevalence of Salmonella-positive flocks was 50% (95% CI: 37, 64) for chickens and 54% (95% CI: 39, 70) for turkeys, respectively. Odds of Salmonella colonization were 2.6 times greater for chicken flocks which failed to lock the chicken house permanently. In turkeys, odds of Salmonella colonization were 4.8-7.7 times greater for flocks which failed to be raised by hatchery. The prevalence of Campylobacter-positive flocks was 35% (95% CI: 22, 49) for chickens and 46% (95% CI: 30, 62) for turkeys. Odds of colonization were 4.1 times higher for chicken flocks raised on farms with professional rodent control and 5.2 times higher for flocks with manure heap >200m from the poultry house, and also increased with the number of birds raised per year on the farm and with the age at slaughter. For turkeys, odds of Campylobacter flock colonization were 3.2 times greater in flocks having a manure heap at house and 4.2 times greater in flocks drinking unchlorinated water.

  17. Examination of egg number and egg weight variables and their effects on daily management in aviary systems for laying hens

    NARCIS (Netherlands)

    Lokhorst, C.; Keen, A.

    1995-01-01

    1. Characteristics of egg numbers and mean egg weight were examined for their usefulness in the daily management of aviary systems for laying hens. 2. A number of 3238 brown Isabrown/Warren hens were housed in 1 compartment, a separated part of the house where the hens could move around freely, of a

  18. Use of space and its impact on the welfare of laying hens in a commercial free-range system.

    Science.gov (United States)

    Rodriguez-Aurrekoetxea, A; Estevez, I

    2016-11-01

    The aim of this study was to explore the factors influencing patterns of space use of commercial free-range laying hens and their relation to welfare indicators. Three free-range laying hen flocks were studied during one production cycle by collecting spatial locations on 150 individually tagged hens per flock. At the end of production, welfare and morphometric measures were collected. The results indicated that use of the outdoor area was lower during midday (P  0.05). Tagged hens were classified according to their use of the outdoor area (heavy, medium, light, or never) per age period. A total of 49.5% were never observed using the outdoor area, which was higher than any other category (P  0.05); only activity center indoors increased (P ranges and activity centers (r = 0.956, r = 0.964 P < 0.05, respectively) and showed lower plumage damage (r = -0.337, P < 0.05) and a lower incidence of footpad dermatitis (r = -0.307, P < 0.05). On the contrary, birds showing higher total walked distance indoors showed a higher incidence of footpad dermatitis (r = 0.329, P < 0.01). We conclude that there exist individual differences in the use of the outdoor area, with early experience (20 to 36 weeks) during the production period being the most relevant factor affecting outdoor area use. Birds visiting the outdoor area more frequently also used larger areas. In addition, individual patterns of space use had some relevance on the incidence on foot pad dermatitis and plumage condition. © 2016 Poultry Science Association Inc.

  19. Effect of humic-plant feed preparations on biochemical blood parameters of laying hens in deep litter housing system.

    Science.gov (United States)

    Bubel, F; Dobrzański, Z; Gaweł, A; Pogoda-Sewerniak, K; Grela, E R

    2015-01-01

    An influence of various humic-plant feed additives based on some herbs (nettle, chamomile, yarrow, perforatum), lucerne and humic materials on biochemical indices of Lohmann Brown (LB) layers blood plasma was estimated. Hens were housed in deep litter system, 20 birds in a group. Four groups were formed: control (C - standard feeding), and experimental, supplemented with prepara- tions: E-1 herbal-humic, E-2 humic-herbal and E-3--humic-lucerne. Hens were placed in the pens on the 16th week of life, addition of preparations with standard food mixture started at the 22nd wk and lasted until 66th wk of life. Blood for analyses was collected four times in the following periods: 27, 37, 54 and 65th wk of life. The applied humic-plant preparations to a limited degree affected the values of examined biochemical parameters in serum: total protein (TP), albumins (Albs), glucose (Glu), urea, triacylglycerols (TAG), total cholesterol (TCh), alanine aminotransferase (ALT), aspartate aminot- ransferase (AST) and alkaline phosphatase (ALP). It is difficult to determine based on these study, which preparation is one the most active biologically, however is seems that humic-lucerne prepara- tion affected the examined blood parameters to the highest degree. The reference values ranges in hens blood serum LB hens were proposed for: TP (43-65 g/l), Albs (15-22 g/l), urea (0.5-1.2 mmol/l), Glu 10-15 mmol/l), TCh (2.2-4.5 mmol/l), TAG (10-24 mmol/l), AST (4-12 U/l), ALT (150-280 mmol/l) and ALP (190-350 U/l).

  20. Investigating behavior changes of laying hens molted by high dietary zinc

    OpenAIRE

    Smayyeh Salari; Somayyeh Salari

    2016-01-01

    Introduction The commercial egg industry commonly uses induced molt procedures to rejuvenate flocks for a second or third laying cycle. Molting may be induced by feed withdrawal for up to 10 days (7), water withdrawal for 2 days (19), or both, along with a reduction of day length (14). Such programs cause concern about animal welfare because it is thought that they may be harmful to hens (28). Given the concerns for potential bird stress, various methods of nutrient restriction that would avo...

  1. Haematological and Biochemical Parameters during the Laying Period in Common Pheasant Hens Housed in Enhanced Cages

    Directory of Open Access Journals (Sweden)

    Petra Hrabčáková

    2014-01-01

    Full Text Available The development of selected haematological and biochemical parameters during the laying period was monitored in common pheasant hens housed in an enhanced cage system. The cages were enhanced by the addition of two perches and a shelter formed by strips of cloth hanging in the corner of the cage. The results showed significant changes in the haematological and biochemical parameters monitored during egg laying. At the time when laying capacity approached a maximum, a decrease was observed (P<0.05 in haematocrit, erythrocytes, and haemoglobin values, whereas monocytes, eosinophils, the heterophil/lymphocyte ratio, phosphorus, and calcium exhibited an increase (P<0.05. At the end of the laying period, an increase (P<0.05 was recorded in the count of leukocytes, heterophils, lymphocytes and basophils, the heterophil to lymphocyte ratio, and the concentrations of aspartate aminotransferase, cholesterol, phosphorus, and calcium, whereas lower values (P<0.05 were recorded for haematocrit and plasma total protein in comparison with the values of the indicators at the beginning of the laying period. The results provide new information about dynamic changes in selected haematological and biochemical parameters in clinically healthy common pheasant hens during the laying period.

  2. Individual Ranging Behaviour Patterns in Commercial Free-Range Layers as Observed through RFID Tracking.

    Science.gov (United States)

    Larsen, Hannah; Cronin, Greg M; Gebhardt-Henrich, Sabine G; Smith, Carolynn L; Hemsworth, Paul H; Rault, Jean-Loup

    2017-03-09

    In this exploratory study, we tracked free-range laying hens on two commercial flocks with Radio Frequency Identification (RFID) technology with the aim to examine individual hen variation in range use. Three distinct outdoor zones were identified at increasing distances from the shed; the veranda [0-2.4 m], close range [2.4-11.4 m], and far range [>11.4 m]. Hens' movements between these areas were tracked using radio frequency identification technology. Most of the hens in both flocks (68.6% in Flock A, and 82.2% in Flock B) accessed the range every day during the study. Of the hens that accessed the range, most hens accessed all three zones (73.7% in Flock A, and 84.5% in Flock B). Hens spent half of their time outdoors in the veranda area. Within-individual consistency of range use (daily duration and frequency) varied considerably, and hens which were more consistent in their daily range use spent more time on the range overall ( p ranging behaviour may help elucidate the implications of ranging for laying hens.

  3. Phosphorus requirement in laying hens

    NARCIS (Netherlands)

    Lambert, W.; Krimpen, van M.M.; Star, L.

    2014-01-01

    It was hypothesized that P supply by feed in alternative housing systems can be lowered without negative effects on bone quality and production performance. Therefore, the objectives of the current study were 1) to update the retainable phosphorus (rP) needs of two modern laying hen breeds from 36

  4. Persistence of vancomycin-resistant enterococci (VRE) in broiler houses after the avoparcin ban

    DEFF Research Database (Denmark)

    Heuer, Ole Eske; Pedersen, Karl; Jensen, Lars Bogø

    2002-01-01

    The glycopeptide growth promoter avoparcin was banned from animal production in the EU in 1997 due to concern for the spread of vancomycin-resistant enterococci (VRE) from food animals to humans. In recent Norwegian and Danish studies, extensive occurrence of VRE on broiler farms and in broiler......, and disinfection of the houses between rotations, and two consecutive broiler flocks from each house were sampled by taking cloacal swabs from the broilers at the time of slaughter. A total of 69 vancomycin-resistant Enterococcus faecium isolates obtained from broiler flocks and broiler houses were subjected......-isolates from different broiler houses and from flocks reared in different houses appeared to be genetically unrelated. These findings indicated that VRE was transmitted between consecutive broiler flocks by clones of resistant. bacteria surviving in the broiler houses despite cleaning and disinfection between...

  5. Lighting during grow-out and Salmonella in broiler flocks

    Directory of Open Access Journals (Sweden)

    Bailey Richard H

    2010-06-01

    Full Text Available Abstract Background Lighting is used during conventional broiler grow-out to modify bird behaviour to reach the goals of production and improve bird welfare. The protocols for lighting intensity vary. In a field study, we evaluated if the lighting practices impact the burden of Salmonella in broiler flocks. Methods Conventional grow-out flocks reared in the states of Alabama, Mississippi and Texas, USA in 2003 to 2006 were sampled 1 week before harvest (n = 58 and upon arrival for processing (n = 56 by collecting feathered carcass rinsate, crop and one cecum from each of 30 birds, and during processing by collecting rinsate of 30 carcasses at pre-chilling (n = 56 and post-chilling points (n = 54. Litter samples and drag swabs of litter were collected from the grow-out houses after bird harvest (n = 56. Lighting practices for these flocks were obtained with a questionnaire completed by the growers. Associations between the lighting practices and the burden of Salmonella in the flocks were tested while accounting for variation between the grow-out farms, their production complexes and companies. Results Longer relative duration of reduced lights during the grow-out period was associated with reduced detection of Salmonella on the exterior of birds 1 week before harvest and on the broiler carcasses at the post-chilling point of processing. In addition, starting reduced lights for ≥18 hours per day later in the grow-out period was associated with decreased detection of Salmonella on the exterior of broilers arriving for processing and in the post-harvest drag swabs of litter from the grow-out house. Conclusions The results of this field study show that lighting practices implemented during broiler rearing can impact the burden of Salmonella in the flock. The underlying mechanisms are likely to be interactive.

  6. Evidence that certain clones of Campylobacter jejuni persist during successive broiler flock rotations

    DEFF Research Database (Denmark)

    Petersen, L.; Wedderkopp, A.

    2001-01-01

    selected. Twelve broiler houses located on 10 farms were included in the study. The C,jejuni isolates collected from the selected houses during the surveillance were typed using fla typing and macrorestriction profiling (MRP), and a subset of the isolates, representing each of the identified clones...... (7 of 13) had fla type 1/1, but MRPs distinguished between isolates from different houses, and fla type 1/1 clones belonged to different serotypes, Seven houses carried persistent clones that covered an interval of at least four broiler flock rotations, or at least one half year. The dominant fla...... with recurrent Campylobacter problems. The MRPs of clones belonging to fla type 1/1 serotype O:2 isolated from persistently infected flocks shared a high percentage of bands compared to the remaining isolates, indicating that some clones that have the ability to cause persistent infections in broiler farms...

  7. U.S. broiler housing ammonia emissions inventory

    Science.gov (United States)

    Gates, R. S.; Casey, K. D.; Wheeler, E. F.; Xin, H.; Pescatore, A. J.

    Using recently published baseline ammonia emissions data for U.S. broiler chicken housing, we present a method of estimating their contribution to an annual ammonia budget that is different from that used by USEPA. Emission rate increases in a linear relationship with flock age from near zero at the start of the flock to a maximum at the end of the flock, 28-65 days later. Market weight of chickens raised for meat varies from "broilers" weighing about 2 kg to "roasters" weighing about 3 kg. Multiple flocks of birds are grown in a single house annually, with variable downtime to prepare the house between flocks. The method takes into account weight and number of chickens marketed. Uncertainty in baseline emissions estimates is used so that inventory estimates are provided with error estimates. The method also incorporates the condition of litter that birds are raised upon and the varying market weight of birds grown. Using 2003 USDA data on broiler production numbers, broiler housing is estimated to contribute 8.8-11.7 kT ammonia for new and built-up litter, respectively, in Kentucky and 240-324 kT ammonia for new and built-up litter, respectively, nationally. Results suggest that a 10% uncertainty in annual emission rate is expected for the market weight categories of broilers, heavy broilers, and roasters. A 27-47% reduction in annual housing emission rate is predicted if new rather than built-up litter were used for every flock. The estimating method can be adapted to other meat bird building emissions and future ammonia emission strategies, with suitable insertion of an age-dependent emission factor or slope into a predictive model equation. The method can be readily applied and is an alternative to that used by USEPA.

  8. Additional information about a mange outbreak by Allopsoroptoides galli (Acari: Psoroptoididae in commercial laying hens in the state of São Paulo, Brazil

    Directory of Open Access Journals (Sweden)

    Edna C. Tucci

    2014-08-01

    Full Text Available This paper reports additional information about a mange outbreak by the mite Allopsoroptoides galli in a commercial egg-laying hen facility in the state of São Paulo, Brazil. About half of the 76,000 multi-age birds of the flock were affected. Experimental infestations carried out on naive hens resulted in clinical signs similar to those diagnosed in naturally infested hens, such as generalized scaly dermatitis, presence of mucus-like material and yellowish crusts on the skin and around the calami, feather loss and strong unpleasant odor. About 30% drop of egg production was estimated. The possible source of infestation were wild birds identified on the ground and roofs of the sheds.

  9. Erysipelas in a free-range layer flock with conjunctival oedema as an unusual clinical sign.

    Science.gov (United States)

    Schmitt, Ferdinand; Schade, Benjamin; Böhm, Brigitte; Shimoji, Yoshihiro; Pfahler, Corinna

    2014-01-01

    Erysipelas was diagnosed in a free-range laying flock with a high mortality of up to 7% per day and a severe decrease in egg production to 45%. The disease had a short course and unusual clinical features for erysipelas, including swollen, lacrimating and encrusted eyes. Bacteriologically, trapped poultry red mites and affected animals were culture-positive for Erysipelothrix rhusiopathiae. Isolates from layers and mites were both serotype 1b. Histopathology revealed disseminated intravasal coagulopathy in conjunctival small vessels as the cause of the oedema of the eye adnexes. After treatment with penicillin, mortality and egg production returned to normal levels. Although erysipelas in laying hens is rarely reported, it can develop as an emerging disease in alternative rearing systems and should always be considered if mortality increases in an older flock, especially with a high infestation of poultry red mites.

  10. Campylobacter spp. contamination of chicken carcasses during processing in relation to flock colonisation.

    Science.gov (United States)

    Allen, V M; Bull, S A; Corry, J E L; Domingue, G; Jørgensen, F; Frost, J A; Whyte, R; Gonzalez, A; Elviss, N; Humphrey, T J

    2007-01-01

    The presence and numbers of campylobacters on chicken carcasses from 26 slaughter groups, originating from 22 single-house flocks and processed in four UK plants, were studied in relation to the level of flock colonisation determined by examining the caecal contents of at least ten birds per group. The prevalence of campylobacters on carcasses from five campylobacter-negative flocks processed just after other negative flocks was low (8.0 log(10) cfu) than carcasses originating from low prevalence flocks (average of 2.3 log(10) cfu; range: defeathering and evisceration areas but not in the chillers. This was the case even when campylobacters were not isolated from the target flock. Campylobacters on carcasses from two partly colonised flocks were either the same subtype, as determined by speciation, Multi-Locus Sequence Typing (MLST) and flaA Restricted Fragment Length Polymorphism (RFLP) typing, as those in the fully colonised flocks processed previously, although not necessarily the most prevalent ones; or were the same subtypes as those found in the caeca of the flock itself. The prevalences of the different campylobacter subtypes found on carcasses from two fully colonised flocks did not closely reflect those found in the caeca. MLST combined with flaA RFLP provided a good method for ascertaining the relatedness of strains isolated from carcasses and caecal contents. This study showed that carcass contamination is related to the within-flock prevalence of campylobacter colonisation, but that contamination from previously processed flocks was also significant, especially on carcasses from low prevalence flocks. Forced dry air cooling of carcasses reduced contamination levels.

  11. PERFORMANCE AND EGGS QUALITY OF HENS OF GENETIC RESOURCES OF THE CZECH REPUBLIC AND SLOVAKIA

    Directory of Open Access Journals (Sweden)

    Zdeněk Ledvinka

    2015-03-01

    Full Text Available The aim of this study was to assess the performance and technological values of eggs of Czech Hen and Oravka breeds housed on litter. The assumption was that the genotype of hens affects their performance, egg weight, and parameters of yolk, albumen and eggshell quality. A total of 30 pullets of Czech Hen breed and 30 pullets of Oravka breed in the age of 17 weeks were included in to the experiment. Environmental conditions corresponded to the standard requirements for laying hens in observed type of housing system. Hen day egg production, egg yield, daily feed consumption per hen, feed consumption per egg and egg weight, egg shape index, proportion and index of yolk and albumen,yolk colour and Haugh units score were monitored in the experiment. From the parameters of eggshell, proportion, thickness, strength and colour of eggshell were observed. Performance parameters of laying hens weren't affected by the genotype of hens. Czech Hen breed showed insignificantly the higher value in all indicators. The significantly (P≤0.01 and P≤0.001 better values of eggshell quality parameters were detected in Czech Hen breed. We found out that Czech Hen breed had also statistically significantly lighter colour of eggshell. There were no significant interbreed differences in egg weight, proportion of yolk and albumen. The egg shape index was significantly higher in Oravka. Index of yolk and albumen was also significantly (P≤0.001 higher in Oravka. Haugh units score, that reflect the quality of the eggs, were found significantly (P≤0.001higher in Oravka too. On the other hand, yolk colour was detected significantly (P≤0.001 darker for the Czech Hen.

  12. Effects of perch on feed consumption and behaviour of caged laying hens

    OpenAIRE

    E. VALKONEN; R. RINNE; J. VALAJA

    2008-01-01

    This experiment studied the effects of perches in furnished cages on behaviour and feed consumption of laying hens. The study used 352 Lohmann Selected Leghorn (LSL) hens. The hens were housed at 16 weeks of age in furnished cages in groups of 8 birds. The experiment lasted for 205 days. The treatments were: perches present from 16 weeks of age (P16), perches present from 19 weeks of age (P19), and no perches present (NP). Feed consumption and egg production were measured over the pre-laying ...

  13. Prevalence and risk factors for Listeria monocytogenes in broiler flocks in Shiraz, southern Iran.

    Science.gov (United States)

    Hosseinzadeh, Saeid; Shekarforoush, Seyed Shahram; Ansari-Lari, Maryam; EsalatPanah-Fard Jahromi, Mehdi; Berizi, Enayat; Abdollahi, Mostafa

    2012-06-01

    Listeria monocytogenes has been identified as an important foodborne pathogen in recent years. In humans, it most commonly affects pregnant women, neonates, children, elderly people, and persons with a suppressed immune system. It could contaminate both raw and cooked meat and poultry products. Studies regarding prevalence and risk factors of L. monocytogenes in broilers flocks are limited. Therefore, the present study was conducted to determine the prevalence and risk factors for L. monocytogenes in poultry flocks in Shiraz, southern Iran. During August to September 2009, in total, 100 broiler flocks were selected at slaughter, and 21 specimens were collected from cloacal samples from each flock. Polymerase chain reaction (PCR) was performed on the samples enriched in buffered Listeria enrichment broth (BLEB), using specific primers. Furthermore, enriched samples in BLEB and/or BLEB treated with 5% KOH were subcultured on Palcam medium. Data about farm and flocks were collected using a structured questionnaire. The prevalence of L. monocytogenes was 7% (95% CI, 2-12%) and 1% using PCR and culture, respectively. Results showed that using antibiotics during rearing period was dramatically reduced the rate of isolation (odds ratio [OR]=0.07, p=0.03), whereas house capacity of more than 10,000 birds (OR=24.03, p=0.04) and number of houses (OR=2, p=0.02) significantly increased the prevalence. The correlation between poor management of large poultry flocks and increasing the risk of contamination was more likely due to the recontamination of cooked poultry/undercooking or cross-contamination of other ready-to-eat foods.

  14. Eggshell apex abnormalities in a free-range hen farm with mycoplasma synoviae and infectious bronchitis virus in Rio de Janeiro state, Brazil

    Directory of Open Access Journals (Sweden)

    FC dos Santos

    2014-06-01

    Full Text Available A farm with 3,000 free-range hens between 24 and 65 weeks of age was investigated. These hens were separated in small flocks of 400 to 700 birds, presenting 10 to 23% egg production reduction. Twenty serum samples were collected during the period of drop in egg production and three weeks later for the investigation of Mycoplasma synoviae (MS, M. gallisepticum (MG and Infectious Bronchitis Virus (IBV antibodies using ELISA. At the time of the second collection, egg production had resumed to normal levels; however, with 10.23% of the eggs showed eggshell abnormalities limited to the apex. Eggshell strength was significantly different between normal and those with eggshell apex abnormalities, but not other egg-quality parameters. ELISA tests showed that MS and IBV titers increased during the evaluated period. MS infection was confirmed by culture and by PCR of tracheal swabs. All samples were negative for MG by ELISA and PCR. Further studies with larger samples to ensure the occurrence of this disease in industrial layer flocks in Brazil are under way.

  15. The effect of space allowance and cage size on laying hens housed in furnished cages, Part II: Behavior at the feeder.

    Science.gov (United States)

    Widowski, T M; Caston, L J; Casey-Trott, T M; Hunniford, M E

    2017-09-01

    Standards for feeder (a.k.a. feed trough) space allowance (SA) are based primarily on studies in conventional cages where laying hens tend to eat simultaneously, limiting feeder space. Large furnished cages (FC) offer more total space and opportunities to perform a greater variety of behaviors, which may affect feeding behavior and feeder space requirements. Our objective was to determine the effects of floor/feeder SA on behavior at the feeder. LSL-Lite hens were housed in FC equipped with a nest, perches, and a scratch mat. Hens with SA of either 520 cm2 (Low; 8.9 cm feeder space/hen) or 748 cm2 (High; 12.8 cm feeder space/hen) per bird resulted in groups of 40 vs. 28 birds in small FC (SFC) and 80 vs. 55 in large FC (LFC). Chain feeders ran at 0500, 0800, 1100, 1400, and 1700 with lights on at 0500 and off at 1900 hours. Digital recordings of FC were scanned at chain feeder onset and every 15 min for one h after (5 scans × 5 feeding times × 2 d) to count the number of birds with their head in the feeder. All occurrences of aggressive pecks and displacements during 2 continuous 30-minute observations at 0800 h and 1700 h also were counted. Mixed model repeated analyses tested the effects of SA, cage size, and time on the percent of hens feeding, and the frequency of aggressive pecks and displacements. Surprisingly, the percent of birds feeding simultaneously was similar regardless of cage size (LFC: 23.0 ± 0.9%; SFC: 24.0 ± 1.0%; P = 0.44) or SA (Low: 23.8 ± 0.9%; High: 23.3 ± 1.0%; P = 0.62). More birds were observed feeding at 1700 h (35.3 ± 0.1%) than any at other time (P Feeder use differed by cage area (nest, middle, or scratch) over the d (P feeder competition at the Low SA in this study. © The Author 2017. Published by Oxford University Press on behalf of Poultry Science Association.

  16. Characterizing the histopathology of natural co-infection with Marek's disease virus and subgroup J avian leucosis virus in egg-laying hens.

    Science.gov (United States)

    Wen, Yawen; Huang, Qi; Yang, Chengcheng; Pan, Ling; Wang, Guijun; Qi, Kezong; Liu, Hongmei

    2018-02-01

    Marek's disease virus (MDV) and avian leucosis virus (ALV) are known to cause tumours in egg-laying hens. Here, we investigated the aetiology of tumours in a flock of egg-laying hens vaccinated against MDV. We carried out gross pathology and histopathological examinations of the diseased tissues, identified virus antigen and sequenced viral oncogenes to elucidate the cause of death in 21-22-week-old hens. At necropsy, diseased hens had distinctly swollen livers, spleens, and proventriculus, and white tumour nodules in the liver. The spleen and liver had been infiltrated by lymphoid tumour cells, while the proventriculus had been infiltrated by both lymphoid tumour cells and myeloblastic cells. Subtype J ALV (ALV-J) and MDV were widely distributed in the proventricular gland cells, and the lymphoid tumour cells in the liver and the spleen. In addition, positive ALV-J signals were also observed in parts of the reticular cells in the spleen. MDV and ALV-J antigens were observed in the same foci of the proventricular gland cells; however, the two antigens were not observed in the same foci from the spleen and liver. The amino acid sequence of the AN-1 (the representative liver tumour tissue that was positive for both ALV-J and MDV) Meq protein was highly similar to the very virulent MDV QD2014 from China. Compared to the ALV-J HPRS-103 reference strain, 10 amino acids (224-CTTEWNYYAY-233) were deleted from the gp85 protein of AN-1. We concluded that concurrent infection with MDV and ALV-J contributed to the tumorigenicity observed in the flock.

  17. Carbon Dioxide and Nitrogen Infused Compressed Air Foam for Depopulation of Caged Laying Hens.

    Science.gov (United States)

    Gurung, Shailesh; White, Dima; Archer, Gregory; Styles, Darrel; Zhao, Dan; Farnell, Yuhua; Byrd, James; Farnell, Morgan

    2018-01-03

    Depopulation of infected poultry flocks is a key strategy to control and contain reportable diseases. Water-based foam, carbon dioxide inhalation, and ventilation shutdown are depopulation methods available to the poultry industry. Unfortunately, these methods have limited usage in caged layer hen operations. Personnel safety and welfare of birds are equally important factors to consider during emergency depopulation procedures. We have previously reported that compressed air foam (CAF) is an alternative method for depopulation of caged layer hens. We hypothesized that infusion of gases, such as carbon dioxide (CO₂) and nitrogen (N₂), into the CAF would reduce physiological stress and shorten time to cessation of movement. The study had six treatments, namely a negative control, CO₂ inhalation, N₂ inhalation, CAF with air (CAF Air), CAF with 50% CO₂ (CAF CO₂), and CAF with 100% N₂ (CAF N₂). Four spent hens were randomly assigned to one of these treatments on each of the eight replication days. A total of 192 spent hens were used in this study. Serum corticosterone and serotonin levels were measured and compared between treatments. Time to cessation of movement of spent hens was determined using accelerometers. The addition of CO₂ in CAF significantly reduced the foam quality while the addition of N₂ did not. The corticosterone and serotonin levels of spent hens subjected to foam (CAF, CAF CO₂, CAF N₂) and gas inhalation (CO₂, N₂) treatments did not differ significantly. The time to cessation of movement of spent hens in the CAF N₂ treatment was significantly shorter than CAF and CAF CO₂ treatments but longer than the gas inhalation treatments. These data suggest that the addition of N₂ is advantageous in terms of shortening time to death and improved foam quality as compared to the CAF CO₂ treatment.

  18. Evaluation of an egg yolk enzyme-linked immunosorbent assay antibody test and its use to assess the prevalence of Mycoplasma gallisepticum infection in laying hens in Italy

    Directory of Open Access Journals (Sweden)

    Marco Tamba

    2010-01-01

    Full Text Available The prevalence of Mycoplasma gallisepticum infection in commercial layers was established by the presence of antibodies in eggs. Saline-extracted yolks were used with a commercial enzyme-linked immunosorbent assay kit. For the prevalence study, yolks from 30 eggs were obtained from each of 66 flocks coming from 36 layer farms. The prevalence of egg antibodies to Mycoplasma gallisepticum was 33.3% in single-age farms and 77.8% in multi-age farms. In 27 flocks, antibody titers were compared with results obtained from blood samples taken in the same flock and in the same period and analyzed with the same kit. This study has confirmed that egg yolk enzyme-linked immunosorbent assay antibody test is a suitable and practical approach for assessing the flock prevalence of Mycoplasma gallisepticum infection in layer hens.

  19. A farm-level study of risk factors associated with the colonization of broiler flocks with Campylobacter spp. in Iceland, 2001 – 2004

    Directory of Open Access Journals (Sweden)

    Berke Olaf

    2007-07-01

    Full Text Available Abstract Background Following increased rates of human campylobacteriosis in the late 1990's, and their apparent association with increased consumption of fresh chicken meat, a longitudinal study was conducted in Iceland to identify the means to decrease the frequency of broiler flock colonization with Campylobacter. Our objective in this study was to identify risk factors for flock colonization acting at the broiler farm level. Methods Between May 2001 and September 2004, pooled caecal samples were obtained from 1,425 flocks at slaughter and cultured for Campylobacter. Due to the strong seasonal variation in flock prevalence, analyses were restricted to a subset of 792 flocks raised during the four summer seasons. Flock results were collapsed to the farm level, such that the number of positive flocks and the total number of flocks raised were summed for each farm. Logistic regression models were fitted to the data using automated and manual selection methods. Variables of interest included manure management, water source and treatment, other poultry/livestock on farm, and farm size and management. Results The 792 flocks raised during the summer seasons originated from 83 houses on 33 farms, and of these, 217 (27.4% tested positive. The median number of flocks per farm was 14, and the median number of positive flocks per farm was three. Three farms did not have any positive flocks. In general, factors associated with an increased risk of Campylobacter were increasing median flock size on the farm (p ≤ 0.001, spreading manure on the farm (p = 0.004 to 0.035, and increasing the number of broiler houses on the farm (p = 0.008 to 0.038. Protective factors included the use of official (municipal (p = 0.004 to 0.051 or official treated (p = 0.006 to 0.032 water compared to the use of non-official untreated water, storing manure on the farm (p = 0.025 to 0.029, and the presence of other domestic livestock on the farm (p = 0.004 to 0.028. Conclusion

  20. Fear, stress, and feather pecking in commercial white and brown laying hen parent-stock flocks and their relationships with production parameters

    NARCIS (Netherlands)

    Haas, de E.N.; Kemp, B.; Bolhuis, J.E.; Groothuis, T.; Rodenburg, T.B.

    2013-01-01

    Little is known about the relationship between welfare traits and production in laying hen parent stock (PS). In commercial laying hens and pure lines, it is known that aspects associated with reduced welfare such as high fear, stress, and feather pecking can have negative effects on production.

  1. Treatment of a field case of avian intestinal spirochaetosis caused by Brachyspira pilosicoli with tiamulin.

    Science.gov (United States)

    Burch, D G S; Harding, C; Alvarez, R; Valks, M

    2006-06-01

    There has been much confusion over the significance of spirochaetes found in the caeca of laying hens and the impact they may have on egg production. In recent years, the situation has been made clearer and the presence of such species as Brachyspira pilosicoli have been shown to cause a mild, chronic disease in both layers and breeders and to reduce egg production by reportedly 5%. In the United Kingdom, a multi-age caged laying site with three separate flocks of approximately 12 000 birds each was chronically infected with B. pilosicoli but displayed few clinical signs except for a noticeable reduction in egg production and an increased mortality. The flocks were treated for 3 days in the drinking water with tiamulin at 12.5 mg/kg bodyweight, and a steady improvement in performance was recorded. The production results were compared with a flock that had been untreated with tiamulin previously, as a control, and one that had been treated at 25 and 45 weeks of age. A 9.8% improvement in egg production/hen housed up to 72 weeks of age and 9.7% in total egg weight was recorded, as well as an 8.6% reduction in actual hen mortality, in the tiamulin-treated flock in comparison with the untreated control. After taking into account the difference in breeds used, there was only a 6% reduction in egg production but an 8.84% increase in mortality in the untreated flock compared with the individual breed's standard production data. The cost of the disease was estimated at 14 million pound in the United Kingdom, based on a national laying flock of 30 million or 1.5% of production. Faecal examination for potentially pathogenic spirochaetes should be part of the differential diagnosis of under-performing laying flocks.

  2. The effect of space allowance and cage size on laying hens housed in furnished cages, Part II: Behavior at the feeder

    Science.gov (United States)

    Widowski, T. M; Caston, L. J; Casey-Trott, T. M; Hunniford, M. E

    2017-01-01

    Abstract Standards for feeder (a.k.a. feed trough) space allowance (SA) are based primarily on studies in conventional cages where laying hens tend to eat simultaneously, limiting feeder space. Large furnished cages (FC) offer more total space and opportunities to perform a greater variety of behaviors, which may affect feeding behavior and feeder space requirements. Our objective was to determine the effects of floor/feeder SA on behavior at the feeder. LSL-Lite hens were housed in FC equipped with a nest, perches, and a scratch mat. Hens with SA of either 520 cm2 (Low; 8.9 cm feeder space/hen) or 748 cm2 (High; 12.8 cm feeder space/hen) per bird resulted in groups of 40 vs. 28 birds in small FC (SFC) and 80 vs. 55 in large FC (LFC). Chain feeders ran at 0500, 0800, 1100, 1400, and 1700 with lights on at 0500 and off at 1900 hours. Digital recordings of FC were scanned at chain feeder onset and every 15 min for one h after (5 scans × 5 feeding times × 2 d) to count the number of birds with their head in the feeder. All occurrences of aggressive pecks and displacements during 2 continuous 30-minute observations at 0800 h and 1700 h also were counted. Mixed model repeated analyses tested the effects of SA, cage size, and time on the percent of hens feeding, and the frequency of aggressive pecks and displacements. Surprisingly, the percent of birds feeding simultaneously was similar regardless of cage size (LFC: 23.0 ± 0.9%; SFC: 24.0 ± 1.0%; P = 0.44) or SA (Low: 23.8 ± 0.9%; High: 23.3 ± 1.0%; P = 0.62). More birds were observed feeding at 1700 h (35.3 ± 0.1%) than any at other time (P < 0.001). Feeder use differed by cage area (nest, middle, or scratch) over the d (P < 0.001). The frequency of aggressive pecks was low overall and not affected by SA or cage size. Frequency of displacements was also low but greater at Low SA (P = 0.001). There was little evidence of feeder competition at the Low SA in this study. PMID:29050409

  3. 9 CFR 145.23 - Terminology and classification; flocks and products.

    Science.gov (United States)

    2010-01-01

    ... house, between 15-20 days prior to the flock being moved to laying quarters. (5) Started poultry shall... being moved to laying quarters. (5) Started poultry shall be delivered to and from the farm premises in... qualification is being sought and (a) infected wild birds, (b) contaminated feed or waste, or (c) birds...

  4. Plumage condition, body weight, mortality, and zootechnical performances: the effects of linings and litter provision in furnished cages for laying hens.

    Science.gov (United States)

    Guinebretière, M; Huneau-Salaün, A; Huonnic, D; Michel, V

    2013-01-01

    This experiment was designed to determine the effect of litter provision and lining in nests and pecking and scratching areas on health and zootechnical performances. Research was carried out in furnished cages, each housing 60 beak-trimmed ISA Brown hens. Four different treatments were compared in a factorial arrangement, including 2 different nest linings (artificial turf versus plastic mesh), either used alone or combined with the use of litter (wheat bran) spread over the rubber mat in the pecking and scratching area (PSA). An additional treatment using artificial turf mat in the PSA and nests (as commonly used in commercial flocks) was used to compare the effect of PSA lining in the other treatments. Zootechnical performances (laying rate, egg weight, and feed intake) were unaffected by PSA lining or by nest lining. The use of artificial turf mats in the PSA resulted in less feather loss than rubber mats, especially on breast and cloaca/vent areas. No consequences were observed on BW or mortality. However, the use of plastic mesh in nests was seen to increase mortality in comparison with artificial turf mats, without affecting plumage condition and BW. Although wheat bran provision did not influence feed intake and laying rate, litter provision did result in slightly higher mean egg weight. Moreover, BW tended to be lower when litter was distributed in cages, and neck and breast plumage condition improved. The distribution of litter was not seen to have any effect on mortality. The provision of litter and the lining of the PSA and nests to improve the welfare of caged laying hens have an effect on mortality, plumage quality, and some zootechnical performances. These results show the importance of choosing the most suitable linings and litter to obtain the best possible compromise between the ethological needs of laying hens, zootechnical performance, and animal health.

  5. Risk factors for Campylobacter colonization in Danish broiler flocks, 2010 to 2011

    DEFF Research Database (Denmark)

    Sandberg, M; Sørensen, L L; Steenberg, B

    2015-01-01

    in the Danish Broiler Production ( KIK: ) database. House- and flock-specific data collected in the surveys were supplemented with information obtained from the KIK database. Data obtained from the two studies were analyzed separately by logistic regression analysis. In both models, the dependent variable...

  6. Salmonella spp. contamination in commercial layer hen farms using different types of samples and detection methods.

    Science.gov (United States)

    Soria, M C; Soria, M A; Bueno, D J; Godano, E I; Gómez, S C; ViaButron, I A; Padin, V M; Rogé, A D

    2017-08-01

    The performance of detection methods (culture methods and polymerase chain reaction assay) and plating media used in the same type of samples were determined as well as the specificity of PCR primers to detected Salmonella spp. contamination in layer hen farms. Also, the association of farm characteristics with Salmonella presence was evaluated. Environmental samples (feces, feed, drinking water, air, boot-swabs) and eggs were taken from 40 layer hen houses. Salmonella spp. was most detected in boot-swabs taken around the houses (30% and 35% by isolation and PCR, respectively) follow by fecal samples (15.2% and 13.6% by isolation and PCR, respectively). Eggs, drinking water, and air samples were negative for Salmonella detection. Salmonella Schwarzengrund and S. Enteritidis were the most isolated serotypes. For plating media, relative specificity was 1, and the relative sensitivity was greater for EF-18 agar than XLDT agar in feed and fecal samples. However, relative sensitivity was greater in XLDT agar than EF-18 agar for boot-swab samples. Agreement was between fair to good depending on the sample, and it was good between isolation and PCR (feces and boot-swabs), without agreement for feed samples. Salmonella spp. PCR was positive for all strains, while S. Typhimurium PCR was negative. Salmonella Enteritidis PCR used was not specific. Based in the multiple logistic regression analyses, categorization by counties was significant for Salmonella spp. presence (P-value = 0.010). This study shows the importance of considering different types of samples, plating media and detection methods during a Salmonella spp. monitoring study. In addition, it is important to incorporate the sampling of floors around the layer hen houses to learn if biosecurity measures should be strengthened to minimize the entry and spread of Salmonella in the houses. Also, the performance of some PCR methods and S. Enteritidis PCR should be improved, and biosecurity measures in hen farms must be

  7. Effect of vaccinating breeder chickens with a killed Salmonella vaccine on Salmonella prevalences and loads in breeder and broiler chicken flocks.

    Science.gov (United States)

    Berghaus, R D; Thayer, S G; Maurer, J J; Hofacre, C L

    2011-05-01

    The objective of this study was to evaluate the effect of vaccination of breeder chickens on Salmonella prevalences and loads in breeder and broiler chicken flocks. Chickens housed on six commercial breeder farms were vaccinated with a killed Salmonella vaccine containing Salmonella Typhimurium, Salmonella Enteritidis, and Salmonella Kentucky. Unvaccinated breeders placed on six additional farms served as controls. Eggs from vaccinated and unvaccinated breeder flocks were kept separately in the hatchery, and the resulting chicks were used to populate 58 commercial broiler flock houses by using a pair-matched design. Vaccinated breeder flocks had significantly higher Salmonella-specific antibody titers than did the unvaccinated breeder flocks, although they did not differ significantly with respect to environmental Salmonella prevalences or loads. Broiler flocks that were the progeny of vaccinated breeders had significantly lower Salmonella prevalences and loads than broiler flocks that were the progeny of unvaccinated breeders. After adjusting for sample type and clustering at the farm level, the odds of detecting Salmonella in samples collected from broiler flocks originating from vaccinated breeders were 62% lower (odds ratio [95% confidence interval] = 0.38 [0.21, 0.68]) than in flocks from unvaccinated breeders. In addition, the mean load of culture-positive samples was lower in broilers from vaccinated breeders by 0.30 log most probable number per sample (95% confidence interval of -0.51, -0.09; P = 0.004), corresponding to a 50% decrease in Salmonella loads. In summary, vaccination of broiler breeder pullets increased humoral immunity in the breeders and reduced Salmonella prevalences and loads in their broiler progeny, but did not significantly decrease Salmonella in the breeder farm environment.

  8. Effect of four processed animal proteins in the diet on digestibility and performance in laying hens.

    Science.gov (United States)

    van Krimpen, M M; Veldkamp, T; Binnendijk, G P; de Veer, R

    2010-12-01

    An experiment was performed to investigate the effect of animal vs. vegetable protein sources in the diet of laying hens on the development of hen performance. A diet containing protein sources of only vegetable origin was compared with 4 diets, each containing 1 of 4 processed animal proteins (PAP). Two PAP (Daka-58 and Sonac-60) were classified as meat meals, and the remaining 2 (Daka-40 and Sonac-50) were classified as meat and bone meals. First, fecal digestibility of nutrients in the PAP was determined in Lohmann Brown layers. Hens (n = 132) were housed in 22 cages (6 hens/cage) and allotted to 5 dietary treatments. In the PAP diets (4 replicates/treatment), 100 g/kg of CP of animal origin was added, replacing soybean meal and corn (Zea mays) in the basal diet (6 replicates/treatment). The PAP sources differed largely in chemical composition and digestibility coefficients. Energy content (AME(n)) varied from 1,817 (Daka-40) to 3,107 kcal/kg (Sonac-60), and digestible lysine varied from 15.4 (Daka-40) to 28.3 g/kg (Sonac-50). Subsequently, the effect of a control diet (without PAP) vs. 4 PAP diets (50 g/kg of CP of animal origin from the same batches as used in the digestibility study) on performance was determined. All diets were isocaloric (AME(n) = 2,825 kcal/kg) and isonitrogenous (digestible lysine = 6.8 g/kg). Hens were housed in 40 floor pens (12 hens/pen, 8 pens/treatment) from 20 to 40 wk of age. Feed intake levels of the hens fed the meat and bone meal diets were reduced compared with those of hens fed the meat meal diets, whereas the feed intake level of hens fed the control diet was intermediate. Laying hen performance differed between treatments, being was most favorable for the Sonac-50 treatment and most adverse for the Daka-40 treatment. Differences in laying hen performance seemed to be related partly to differences in feed intake and corresponding amino acid intake.

  9. Flock House virus subgenomic RNA3 is replicated and its replication correlates with transactivation of RNA2

    International Nuclear Information System (INIS)

    Eckerle, Lance D.; Albarino, Cesar G.; Ball, L. Andrew.

    2003-01-01

    The nodavirus Flock House virus has a bipartite genome composed of RNAs 1 and 2, which encode the catalytic component of the RNA-dependent RNA polymerase (RdRp) and the capsid protein precursor, respectively. In addition to catalyzing replication of the viral genome, the RdRp also transcribes from RNA1 a subgenomic RNA3, which is both required for and suppressed by RNA2 replication. Here, we show that in the absence of RNA1 replication, FHV RdRp replicated positive-sense RNA3 transcripts fully and copied negative-sense RNA3 transcripts into positive strands. The two nonstructural proteins encoded by RNA3 were dispensable for replication, but sequences in the 3'-terminal 58 nucleotides were required. RNA3 variants that failed to replicate also failed to transactivate RNA2. These results imply that RNA3 is naturally produced both by transcription from RNA1 and by subsequent RNA1-independent replication and that RNA3 replication may be necessary for transactivation of RNA2

  10. Effects of two different rearing systems (organic and barn on production performance, animal welfare traits and egg quality characteristics in laying hens

    Directory of Open Access Journals (Sweden)

    Luigi Guidobono Cavalchini

    2010-01-01

    Full Text Available Alternative housing systems for hen eggs production represents clear evidence of the trend in animal housing and husbandry towards extensive rearing methods. Consumer demand is oriented towards healthy foods controlled not only under a safety point of view, but also under a welfare assessment of the animals’ living conditions. Among the different alternative systems deep litter and organic production in recent years have been improved in Italy. The aim of this study was to evaluate whether different housing systems (barn B and organic O for laying hens may influence productive performance, fear responses and egg quality characteristics. A total of 4,745 birds were housed in the B system and 2,016 in the O system, both of which were commercial facilities. In each system the same strain (Hy-Line Brown was housed and layer performance, external and internal egg characteristics, mortality and feed consumption were recorded weekly. Animal reactivity was recorded monthly with the approaching test. Moreover, the Tonic Immobility test was conducted at 70 weeks of age; feather and foot pad conditions were also investigated at the same time. The peak of laying was reached in both housing systems at 25 weeks of age and was higher in organic hens (94.5% than in barn hens (93.0%. Feed conversion rate during the overall laying period was 2.36 vs 2.20, respectively, in O and B housing systems. There was a significant difference concerning the eggs classified as very dirty, dirty and cracked between the two systems. The dirty eggs were higher in O system probably due to laying eggs in a free range area, while the higher number of cracked eggs in B system may be due to a significantly less shell thickness in this system. Egg weight increased with layer age in both housing systems. Animals reared in O system showed less fearfulness than in B emphasised by the approaching and Tonic Immobility test results. Feather scoring did not evidence any severe plumage

  11. Production of Bio-omega-3 eggs through the supplementation of extruded flaxseed meal in hen diet.

    Science.gov (United States)

    Imran, Muhammad; Anjum, Faqir Muhammad; Nadeem, Muhammad; Ahmad, Nazir; Khan, Muhammad Kamran; Mushtaq, Zarina; Hussain, Shahzad

    2015-10-09

    The full-fat flaxseed meal has obtained relatively new flourished concept as staple chicken feedstuff for the production of designer eggs. However, unprocessed flaxseed also encloses well documented anti-nutritional factors which are associated with growth depression of laying hens. The present research work was carried out to evaluate the impact of full-fat extruded flaxseed meal supplemented diets on productivity performance of hens and production of modified ω-3 fatty acids-enriched eggs. The full-fat flaxseed meal was extruded at barrel exit temperature (140 °C), screw speed (160 rpm) and feed rate (25 kg/h) for reduction of anti-nutritional compounds. One hundred and sixty, Babcock hens (age 24 weeks old) were selected at random from a large flock and ten hens were placed in each of 16 wire-mesh pens. The experimental diets prepared by supplementation of extruded flaxseed at 10%, 20% and 30% level were fed to hens along with control. The extruded flaxseed contained 86% and 76% less hydrocyanic compounds and tannin, respectively than the initial material. The hens fed with control diet consumed more feed, possessed heavy body weight and showed higher egg production as compared to hens fed on extruded flaxseed supplemented diets. The loss in body weight and egg production was recorded less for hens fed on 10% extruded flaxseed supplemented diets as compared to those fed on 30% extruded flaxseed supplemented diets. None of the experimental diets resulted in significant increase or decrease the total lipids and cholesterol content in egg yolk of hens. The extruded flaxseed supplemented diets resulted in a significant improvement of α-linolenic and docosahexaenoic acid in egg yolk with a concomitant reduction in arachidonic acid. The sensory scores were assigned higher to control eggs. Increasing level of extruded flaxseed in experimental diets decreased the scores for all sensory attributes of eggs. The present study suggested that extruded flaxseed meal up to

  12. Mass depopulation of laying hens in whole barns with liquid carbon dioxide: evaluation of welfare impact.

    Science.gov (United States)

    Turner, P V; Kloeze, H; Dam, A; Ward, D; Leung, N; Brown, E E L; Whiteman, A; Chiappetta, M E; Hunter, D B

    2012-07-01

    Appropriate emergency disaster preparedness is a key priority for agricultural agencies to allow effective response to serious avian disease outbreaks. There is a need to develop rapid, humane, and safe depopulation techniques for poultry that are widely applicable across a range of farm settings. Whole barn depopulation with carbon dioxide (CO(2)) has been investigated as a humane and efficient means of killing large numbers of birds in the event of a reportable disease outbreak. It has also been considered as a method for depopulating barns containing end-of-lay hens, particularly when there is limited local slaughter and rendering capacity. Determining the best method of humanely killing large flocks of birds remains problematic and is being investigated by a coordinated international effort. While whole barn depopulation using CO(2) inhalation has been explored, physiologic responses of chickens have not been characterized in field settings and assessment of animal welfare is hampered without this information. In this study, 12 cull laying hens were surgically instrumented with telemetry transmitters to record electroencephalographs, electrocardiographs, body temperature, and activity during 2 large-scale field CO(2) euthanasia trials of end-of-lay hens. The day following surgery, instrumented hens were placed in barns with other birds, barns were sealed, and animals were killed by CO(2) inhalation delivered via a specially designed liquid CO(2) manifold. Instrumented birds were monitored by infrared thermography, and ambient temperature, CO(2), and O(2) concentrations were recorded. Results from these studies indicate that instrumented hens lost consciousness within 2 min of CO(2) levels reaching 18 to 20%. Mild to moderate head shaking, gasping, and 1 to 2 clonic muscle contractions were noted in hens before unconsciousness; however, brain death followed rapidly (benefits suggest clear advantages over catching and transporting cull hens for slaughter. The

  13. High, low, or familiar? Nest site preferences of experienced laying hens.

    Science.gov (United States)

    Krause, E T; Schrader, L

    2018-05-22

    1. The aim of this study was to investigate which nest heights are preferred by laying hens in the absence of familiar nest locations and whether preferred nest heights are more attractive than a familiar location. In two experiments, a total of 108 hens of four different layer breeds, which were at least 50 weeks of age, were studied. 2. In the first experiment, hens were given individual free choice between nests for 1-week at four different heights (0 cm, 39 cm, 78 cm, and 117 cm above ground). Hens of the four breeds differed in their nest height preferences (P = 0.0013). However, hens of three breeds preferred ground level nests (P < 0.007) and the fourth line showed an equal preference for the ground level and level three, the latter level corresponding to the height of the nests in their home compartments. 4. In the second experiment, hens from the four breeds were given a choice between ground level nests and nests at a familiar location, i.e. at the same location as in their home compartment. Hens of all strains preferred the familiar nest location (P = 0.002) and preferences did not differ between strains (P = 0.77). 5. Laying hens seem to prefer nests at ground level in the absence of a familiar nest. However, if possible, experienced 50 week old hens continue to use a familiar nest location instead of a ground nest location. The results are discussed with respect to a potential primary preference that may be modifiable by experience and with respect to possible relevance in commercial housing.

  14. Estimation of total genetic effects for survival time in crossbred laying hens showing cannibalism, using pedigree or genomic information

    NARCIS (Netherlands)

    Brinker, T.; Raymond, B.; Bijma, P.; Vereijken, A.; Ellen, E.D.

    2017-01-01

    Mortality of laying hens due to cannibalism is a major problem in the egg-laying industry. Survival depends on two genetic effects: the direct genetic effect of the individual itself (DGE) and the indirect genetic effects of its group mates (IGE). For hens housed in sire-family groups, DGE and

  15. Laying hen movement in a commercial aviary: Enclosure to floor and back again.

    Science.gov (United States)

    Campbell, D L M; Makagon, M M; Swanson, J C; Siegford, J M

    2016-01-01

    Many producers in the laying hen industry, including in North America, are phasing out conventional cages in response to consumer demands and sometimes subsequent legislation. Alternative housing systems such as aviaries are being implemented in an attempt to improve hen welfare. Aviaries provide additional space and resources to groups of hens, including a litter area on the floor. However, little is known about hen movement between tiered enclosures and floor litter areas in aviary systems. Diurnal rhythms and social attraction may result in peak times of movement that could lead to overcrowding of areas, or alternatively hen preferences may lead to some areas not being fully utilized. We monitored hen movement between tiered enclosures and litter areas, including movement on and off the outer perch, across the day at peak, mid and end of lay in a commercial aviary. Hens moved onto and off of the open litter area across the day, transitioning between tiered enclosures, outer perches, open litter areas, and litter areas under tiered enclosures. At certain times of day, there were periods of greater hen movement down to the open litter area and between litter areas. For example, more hens were typically observed exiting enclosures, jumping from perches to open litter, and traveling between open litter and litter under tiered enclosures in the morning (all P ≤ 0.001). In all but one instance, more hens were observed on open litter areas in the afternoon than at other times of day (all P ≤ 0.029). However, hen re-entry to tiered enclosures showed less circadian patterning. Hen movement was observed between areas of interest at all sampled time periods, indicating hens use all areas of the system. Further research should examine whether all individual hens do move between areas equally, including within levels of the tiered enclosure, or if crowding occurs on the outer perches or in the litter during times of peak movement. © 2015 Poultry Science Association Inc.

  16. Coordinated Behaviour in Pigeon Flocks

    OpenAIRE

    Yomosa, Makoto; Mizuguchi, Tsuyoshi; V?s?rhelyi, G?bor; Nagy, M?t?

    2015-01-01

    We analysed pigeon flock flights using GPS trajectory data to reveal the most important kinematic aspects of flocking behaviour. We quantitatively investigated the internal motion of the flock based on pairwise statistics and found the following general relationships in all datasets: i) the temporal order of decisions characterised by the delay between directional changes is strictly related to the spatial order characterised by the longitudinal relative position within the flock; ii) during ...

  17. Interactions of genotype, housing and dietary calcium in layer ...

    African Journals Online (AJOL)

    The study was designed to evaluate the interactions in performance, eggshell quality and tibia traits of two laying hen genotypes, namely a commercial hybrid, Lohmann (LSL), and a traditional breed, the Czech Hen (CH), housed in conventional cages and on litter, and fed two levels of dietary calcium (Ca) (3.5% vs. 3.0%).

  18. Hydrodynamics of Turning Flocks

    OpenAIRE

    Yang, Xingbo; Marchetti, M. Cristina

    2014-01-01

    We present a hydrodynamic model of flocking that generalizes the familiar Toner-Tu equations to incorporate turning inertia of well-polarized flocks. The continuum equations controlled by only two dimensionless parameters, orientational inertia and alignment strength, are derived by coarse graining the inertial spin model recently proposed by Cavagna et al. The interplay between orientational inertia and bend elasticity of the flock yields anisotropic spin waves that mediate the propagation o...

  19. Laying hens behave differently in artificially and naturally sourced ammoniated environments.

    Science.gov (United States)

    Pokharel, B B; Dos Santos, V M; Wood, D; Van Heyst, B; Harlander-Matauschek, A

    2017-12-01

    Laying hens are chronically exposed to high levels of ammonia (NH3), one of the most abundant aerial pollutants in poultry houses. Tests for aversion to NH3 in laying hens have used artificially sourced NH3/air mixtures (i.e., from a gas cylinder) showing that birds prefer fresh air to NH3. However, artificially sourced NH3/air mixtures may not accurately reflect barn air conditions, where manure emits a variety of gases. Herein, we investigated whether laying hens differentiate between artificially and naturally sourced NH3/air mixtures and how exposure to NH3 affects foraging and aversive behavior. A total of 20 laying hens was exposed to artificially sourced [A] (from an anhydrous NH3 cylinder) and naturally sourced [N] (from conspecific laying hen excreta) gas mixtures. Hens were exposed to A and N mixtures with NH3 concentrations of 25 and 45 ppm, as well as fresh air [FA]. During the experiment, all birds were exposed to each treatment 3 times using a custom-built polycarbonate chamber, containing a foraging area (containing raisins, mealworms, and feed mix) and a gas delivery system. All testing sessions were video recorded, analyzed with INTERACT® software, and subjected to a GLIMMIX procedure in SAS. Our results showed that the laying hens spent less time foraging overall (P hens were more likely to forage for a longer time (with fewer interruptions) in N than in A treatments (P hens also reacted with greater aversion towards treatment A compared to treatment N (P hens of our study preferred fresh to ammoniated air and that they behaved differently in artificially and naturally sourced NH3/air mixtures, possibly due to the presence of familiar stimuli from the excreta. These findings have implications for new developments in methodological approaches for behavioral testing and for recommendations regarding NH3 levels inside poultry barns. © 2017 Poultry Science Association Inc.

  20. Selection for low mortality in laying hens affects catecholamine levels in the arcopallium, a brain area involved in fear and motor regulation

    NARCIS (Netherlands)

    Kops, M.S.; Haas, de E.N.; Rodenburg, T.B.; Ellen, E.D.; Korte-Bouws, G.A.H.; Olivier, B.; Güntürkün, O.; Korte, S.M.; Bolhuis, J.E.

    2013-01-01

    Feather pecking (FP) in laying hens may cause mortality due to cannibalism. Novel breeding methods using survival days of group-housed siblings allow for the genetic selection of laying hens with low mortality (LML: low mortality line) due to cannibalism. Previous studies have demonstrated less

  1. Morphology of immune organs after very virulent plus strain of Marek's disease virus infection in vaccinated hens.

    Science.gov (United States)

    Madej, J P; Woźniakowski, G; Gaweł, A

    2016-01-01

    Marek's disease (MD) outbreaks in poultry flocks may be associated with overriding of vaccine immune protection by very virulent (vvMDV) or very virulent plus (vv+MDV) strains. This paper presents the study on lymphoid organ morphology in the latent phase of MD caused by vv+MDV which break post-vaccinal protection in hens. We also immunohistochemically examined B and T populations as well as B/T and CD4+/CD8+ ratio of lymphocytes in lymphatic organs and, as a background, in MD lymphomas from non-lymphatic organs. The number of antigen expressed cells was evaluated as a percentage of positive cells in the one power field. Organ samples were collected from 24 dead reproductive hens (Ross 308 line) in age between 35-56 weeks, infected with vv+MDV. The hens originated from farms with MD outbreaks, despite earlier routine vaccination with CVI988/Rispens + HVT. The control organ samples originated from 15 clinically healthy hens at the same age and line, subjected to the same vaccination schedule. The number of CD3+, CD8+ and TCRγδ+ cells was significantly lower in MDV infected thymus, spleen and cecal tonsils in comparison to that found in the control organs. The proportion of CD4+ was also distinctly reduced in the thymus and limited in the spleen of MDV infected hens. This study revealed that infection with field vv+MDV isolates might break post-vaccinal protection and influence the central and peripheral immune system. The decrease in CD8+ and TCRγδ+ cell number in the thymus, spleen and cecal tonsils suggests that primarily these cells are involved in cell-mediated cytotoxicity against MDV transformed cells during latency.

  2. The cis-acting replication signal at the 3' end of Flock House virus RNA2 is RNA3-dependent

    International Nuclear Information System (INIS)

    Albarino, Cesar G.; Eckerle, Lance D.; Ball, L. Andrew

    2003-01-01

    The nodavirus Flock House virus has a bipartite positive-sense RNA genome consisting of RNAs 1 and 2, which encode the viral RNA-dependent RNA polymerase (RdRp) and capsid protein precursor, respectively. The RdRp catalyzes replication of both genome segments and produces from RNA1 a subgenomic RNA (RNA3) that transactivates RNA2 replication. Here, we replaced internal sequences of RNAs 1 and 2 with a common heterologous core and were thereby able to test the RNA termini for compatibility in supporting the replication of chimeric RNAs. The results showed that the 3' 50 nt of RNA2 contained an RNA3-dependent cis-acting replication signal. Since covalent RNA dimers can direct the synthesis of monomeric replication products, the RdRp can evidently respond to cis-acting replication signals located internally. Accordingly, RNA templates containing the 3' termini of both RNAs 1 and 2 in tandem generated different replication products depending on the presence or absence of RNA3

  3. Causes of keel bone damage and their solutions in laying hens

    NARCIS (Netherlands)

    Harlander-Matauschek, A.; Rodenburg, T.B.; Sandilands, V.; Tobalske, B.W.; Toscano, M.J.

    2015-01-01

    Keel bone damage (KBD) is a critical issue facing the contemporary laying hen industry due to the likely pain leading to compromised welfare and reduced productivity. Recent reports suggest that KBD, while highly variable and likely dependent on a host of factors, extends to all housing systems

  4. Effects of a premolt calcium and low-energy molt program on laying hen behavior and heterophil-to-lymphocyte ratios.

    Science.gov (United States)

    Dickey, E R; Bregendahl, K; Stalder, K; Fitzgerald, R; Johnson, A K

    2010-11-01

    The objectives of this study were to compare the behaviors, postures, and heterophil-to-lymphocyte ratios (H:L) of laying hens housed in a cage system when offered a Ca premolt treatment and low-energy molt diets vs. a traditional feed withdrawal (FW) treatment during and after molt. A total of 144 Hy-Line W-36 hens (85 wk of age), housed 3 hens/cage (413 cm(2)/hen), were used. Hens were allotted to treatments according to a randomized complete block design, with the cage location and initial BW as the blocking criteria. Six treatments were compared in a 2 × 3 factorial arrangement with 2 Ca premolt treatments (fine or coarse) and 3 low-energy molt diets (FW, soybean hulls, or wheat middlings). The 2 Ca premolt treatments differed only in Ca particle size (fine was 0.14 mm and coarse was 2.27 mm mean diameter). Two postures and 5 behaviors were recorded and H:L was measured. Data were analyzed using the MIXED procedure of SAS, with P postures, or H:L during the premolt baseline period. The Ca premolt treatment had no carryover effects during or after molt for behaviors or postures. During molt, hens in the FW treatment were more active, and they ate and drank less compared with hens fed soybean hulls or wheat middlings, but there were no differences in aggression, nonnutritive pecking, or sitting. Drinking and aggression during and after molt were not different, but hens postmolt engaged in more sitting and feeding and less activity, nonnutritive pecking, and preening compared with during molt. There were no differences in H:L during or after molt. In conclusion, a Ca premolt treatment did not affect the behavior of the laying hen. The low-energy molt diets did not adversely affect behavior compared with FW and did not increase H:L; therefore, they could be useful alternatives for inducing molt in laying hens.

  5. Investigating behavior changes of laying hens molted by high dietary zinc

    Directory of Open Access Journals (Sweden)

    Smayyeh Salari

    2016-11-01

    Full Text Available Introduction The commercial egg industry commonly uses induced molt procedures to rejuvenate flocks for a second or third laying cycle. Molting may be induced by feed withdrawal for up to 10 days (7, water withdrawal for 2 days (19, or both, along with a reduction of day length (14. Such programs cause concern about animal welfare because it is thought that they may be harmful to hens (28. Given the concerns for potential bird stress, various methods of nutrient restriction that would avoid long term feed withdrawal have been investigated (20, 24. One of the alternative methods for molt induction is high-dietary Zn (4. Materials and Methods In this study, a total of 30 Hy-line W-36 leghorn hens (at 50 wk old (1400 ± 150 g, were randomly assigned to 5 replicate. Ten cages (3 hens in each cage on both the upper and lower tiers were considered to observe behavior patterns. Data recording of predetermined behavioral patterns were carried out using five Camera Digital Video Recorder Multiplexer System. Behavior recording began at 9:00 h each day and ended at 11:00 h and a second observation starting at 16:00 p.m and ended at 18:00 p.m. Total of ten cages (containing 3 hens/ cage (30 hens total were used to collect 5 behaviors (feeding, drinking, nonnutritive pecking, preening and aggression pecking and one posture (sitting. The following ethogram was adopted from Webster (27 feeding defined as pecking behavior directed toward the feed trough or toward a neighboring feed trough. Drinking was defined as the appearance of ingesting water from the nipple at the near of the cage. Nonnutritive pecking was defined as non aggressive pecking at anything other than feed, which included cage pecking, feather pecking, bill pecking and air pecking. Preening behavior involved the manipulation of the plumage with the beak. Aggressive was the sum of pecks that occurred within a cage or between neighboring cages. Sitting was defined as a crouched posture with shanks

  6. Estimation of the sensitivity of various environmental sampling methods for detection of Salmonella in duck flocks.

    Science.gov (United States)

    Arnold, Mark E; Mueller-Doblies, Doris; Gosling, Rebecca J; Martelli, Francesca; Davies, Robert H

    2015-01-01

    Reports of Salmonella in ducks in the UK currently rely upon voluntary submissions from the industry, and as there is no harmonized statutory monitoring and control programme, it is difficult to compare data from different years in order to evaluate any trends in Salmonella prevalence in relation to sampling methodology. Therefore, the aim of this project was to assess the sensitivity of a selection of environmental sampling methods, including the sampling of faeces, dust and water troughs or bowls for the detection of Salmonella in duck flocks, and a range of sampling methods were applied to 67 duck flocks. Bayesian methods in the absence of a gold standard were used to provide estimates of the sensitivity of each of the sampling methods relative to the within-flock prevalence. There was a large influence of the within-flock prevalence on the sensitivity of all sample types, with sensitivity reducing as the within-flock prevalence reduced. Boot swabs (individual and pool of four), swabs of faecally contaminated areas and whole house hand-held fabric swabs showed the overall highest sensitivity for low-prevalence flocks and are recommended for use to detect Salmonella in duck flocks. The sample type with the highest proportion positive was a pool of four hair nets used as boot swabs, but this was not the most sensitive sample for low-prevalence flocks. All the environmental sampling types (faeces swabs, litter pinches, drag swabs, water trough samples and dust) had higher sensitivity than individual faeces sampling. None of the methods consistently identified all the positive flocks, and at least 10 samples would be required for even the most sensitive method (pool of four boot swabs) to detect a 5% prevalence. The sampling of dust had a low sensitivity and is not recommended for ducks.

  7. Hydrodynamics and phases of flocks

    International Nuclear Information System (INIS)

    Toner, John; Tu Yuhai; Ramaswamy, Sriram

    2005-01-01

    We review the past decade's theoretical and experimental studies of flocking: the collective, coherent motion of large numbers of self-propelled 'particles' (usually, but not always, living organisms). Like equilibrium condensed matter systems, flocks exhibit distinct 'phases' which can be classified by their symmetries. Indeed, the phases that have been theoretically studied to date each have exactly the same symmetry as some equilibrium phase (e.g., ferromagnets, liquid crystals). This analogy with equilibrium phases of matter continues in that all flocks in the same phase, regardless of their constituents, have the same 'hydrodynamic'-that is, long-length scale and long-time behavior, just as, e.g., all equilibrium fluids are described by the Navier-Stokes equations. Flocks are nonetheless very different from equilibrium systems, due to the intrinsically nonequilibrium self-propulsion of the constituent 'organisms'. This difference between flocks and equilibrium systems is most dramatically manifested in the ability of the simplest phase of a flock, in which all the organisms are, on average moving in the same direction (we call this a 'ferromagnetic' flock; we also use the terms 'vector-ordered' and 'polar-ordered' for this situation) to exist even in two dimensions (i.e., creatures moving on a plane), in defiance of the well-known Mermin-Wagner theorem of equilibrium statistical mechanics, which states that a continuous symmetry (in this case, rotation invariance, or the ability of the flock to fly in any direction) can not be spontaneously broken in a two-dimensional system with only short-ranged interactions. The 'nematic' phase of flocks, in which all the creatures move preferentially, or are simply oriented preferentially, along the same axis, but with equal probability of moving in either direction, also differs dramatically from its equilibrium counterpart (in this case, nematic liquid crystals). Specifically, it shows enormous number fluctuations, which

  8. Coordinated Behaviour in Pigeon Flocks.

    Directory of Open Access Journals (Sweden)

    Makoto Yomosa

    Full Text Available We analysed pigeon flock flights using GPS trajectory data to reveal the most important kinematic aspects of flocking behaviour. We quantitatively investigated the internal motion of the flock based on pairwise statistics and found the following general relationships in all datasets: i the temporal order of decisions characterised by the delay between directional changes is strictly related to the spatial order characterised by the longitudinal relative position within the flock; ii during circling motion, pigeons use a mixture of two idealised and fundamentally different turning strategies, namely, parallel-path and equal-radius type turning. While pigeons tend to maintain their relative position within the flock on average, as in the parallel-path approximation, those who turn later also get behind as in the equal-radius case. Equal-radius type turning also tends to be expressed more during smaller radius turns.

  9. Village poultry production in the Sudan

    International Nuclear Information System (INIS)

    Khalafalla, A.I.; Awad, S.; Hass, W.

    2002-01-01

    A survey form provided by the Joint FAO/IAEA Division was used to collect data on village poultry production in the Sudan. The production system in the households was based on scavenging indigenous domestic chickens, at times accompanied by pigeons, guinea fowls, ducks or turkeys. The average flock size was 18.8 birds and included 44.3% hens, 10% cocks, 20% growers and 24.8% chicks. The hen to cock ratio was 4.4:1. Average egg production was 3.1 per hen per month, of which 76% were incubated by hens. About 78% of incubated eggs hatched of which 75% survived the brooding period. Approximately half of the households provided the chickens with housing. Around 25.7% of interviewed households used chicken manure as fertilizer. While scavenging, chickens fed on insects, grass, vegetables and kitchen wastes. Feed supplements included sorghum, millet and sometimes wheat bran and alfalfa. The ownership of village chickens was shared between all gender categories and all were involved in the management of the birds. The major constraints to village poultry production in the Sudan were identified and included inadequate health care, poor production, inappropriate housing and poor knowledge of poultry management. (author)

  10. Effect of climate and farm environment on Campylobacter spp. colonisation in Norwegian broiler flocks.

    Science.gov (United States)

    Jonsson, Malin E; Chriél, Mariann; Norström, Madelaine; Hofshagen, Merete

    2012-11-01

    Campylobacteriosis is the most frequently reported zoonosis in the EU. A recent report states that between 50% and 80% of the human campylobacteriosis cases could be attributed to broiler as a reservoir. The current study was conducted to investigate associations between the presence of Campylobacter spp. in Norwegian broiler flocks and factors related to the climate and the farm environment. Data from 18,488 broiler flocks from 623 different farms during 2002-2007 were included in the study. A logistic regression analysis was conducted where Campylobacter spp. status of a broiler flock at the time of slaughter was defined as the dependent variable and farm was modelled as a random effect. The following factors were found to increase the probability for a broiler flock to test positive for Campylobacter spp.: daily mean temperature above 6°C during the rearing period, private water supply, presence of other livestock farms within a distance of 2 km, presence of other broiler farms within a distance of 4 km with flocks positive for Campylobacter spp. within 30 days prior to slaughter, heavy rainfall 11-30 days prior to slaughter, region and year. Daily mean temperature below 0°C reduced the probability. The study emphasises the importance of the farm environment and the climate for the occurrence of Campylobacter spp. in broiler flocks. The farm environment is probably a part of the Campylobacter spp. pathway into and between broiler flocks where farmyard run-off and humans or flies entering the houses might constitute vehicles transporting the organism. Fly activity is temperature-driven and flies might be a part of the explanation of the increased risk for Campylobacter spp. related to increased temperature demonstrated in the study. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Variability and interaction of some egg physical and eggshell quality attributes during the entire laying hen cycle.

    Science.gov (United States)

    Sirri, F; Zampiga, M; Berardinelli, A; Meluzzi, A

    2018-05-01

    The aim of this study was to investigate the variability and relationships between some egg physical (egg weight, width, length, shape index, and surface area) and eggshell parameters (weight and percentage, thickness, breaking strength, and L*, a*, and b* values) during the entire laying hen cycle. A total of 8,000 eggs was collected every 5 wk, from 30 to 81 wk of hen age (10 samplings of 400 eggs/house), in 2 identical poultry houses equipped with enriched cages. For the statistical analysis, ANOVA, Bivariate Correlation, Principal Component Analysis (PCA), and Hierarchical Cluster Analysis were used. An increase of egg weight, length, and eggshell lightness (L*) associated with a reduction of eggshell percentage, breaking strength, and redness (a*) was observed as the hen aged (P 10% of eggshell breaking strength and a*. According to the PCA, the highest changes during the laying cycle are related to egg physical parameters (32%) and to eggshell breaking strength, percentage, and thickness (26%). The egg physical parameters appeared to be strongly correlated to each other, whereas a slight correlation between eggshell breaking strength and color attributes were evidenced (-0.231 and 0.289, respectively, for L* and a*; P quality attributes throughout the entire laying hen cycle.

  12. Production performance, use of nest box, and external appearance of two strains of laying hens kept in conventional and enriched cages.

    Science.gov (United States)

    Onbaşılar, E E; Ünal, N; Erdem, E; Kocakaya, A; Yaranoğlu, B

    2015-04-01

    The aim of this study was to investigate the differences in production performance, use of nest box, and external appearance of 2 strains of laying hens kept in conventional and enriched cages. Lohmann Brown Classic (LB, n=532) and Lohmann LSL Classic (LW, n=532) hens were housed from 16 to 73 wk in either conventional cages or enriched cages. Enriched cages had a nesting area, scratch pad, perch, and nail shortener. Body weight (BW), hen-day egg production, egg weight, feed intake, feed conversion ratio (FCR), cracked and dirty eggs, use of nest box for lay, and external appearance were determined. Laying period influenced the hen-day egg production, egg weight, feed intake, and feed conversion ratio. Cage type affected the hen-day egg production and feed conversion ratio, while strain affected the egg weight, feed intake, and feed conversion ratio. Laying period×cage type and laying period×strain interactions affected egg production, egg weight, and feed conversion ratio. Both strains preferred to lay in the nest box. Percentages of cracked and dirty eggs of LW hens in enriched cages were higher than that in conventional cages. Most of the dirty eggs laid by both strains were found outside of the nest box. The LW hens laid more dirty eggs than the LB hens. Cage type and cage type×strain interaction were important for total feather score. Final claw length was affected by cage type, strain, and cage type×strain interaction. This study suggests that cage type, strain, and also cage type×strain and period×strain interactions should be considered when alternative housing systems are used. © 2015 Poultry Science Association Inc.

  13. Henning Bergenholtz

    DEFF Research Database (Denmark)

    Schoonderbeek Hansen, Inger

    2013-01-01

    Kort redegørelse for Professor for Center for Leksikografi, Henning Bergenholtz' fratrædelse 18.01.2013......Kort redegørelse for Professor for Center for Leksikografi, Henning Bergenholtz' fratrædelse 18.01.2013...

  14. Anaphylactic reaction to probiotics. Cow's milk and hen's egg allergens in probiotic compounds.

    Science.gov (United States)

    Martín-Muñoz, María Flora; Fortuni, Monserrat; Caminoa, Magdalena; Belver, Teresa; Quirce, Santiago; Caballero, Teresa

    2012-12-01

    Probiotics are used in the treatment of allergic diseases. We investigated the safety of probiotics for subjects with food allergy. Labels of probiotics commercially available in Spain were examined to assess their content of cow's milk or hen's egg. Skin prick tests with these compounds (20 mg/ml) were performed in five children allergic to cow's milk, five children allergic to hen's white egg, and five control subjects non-allergic to food. Three serum pools: I (positive-specific IgE to cow's milk and hen's egg white proteins), II (positive-specific IgE to cow's milk and negative to hen's egg white proteins), and III (negative-specific IgE to cow's milk and positive to hen's egg white proteins) were used to detect cow's milk and hen's egg white allergens in probiotics. ImmunoCAP(®) (Phadia), in-house ELISA, SDS-PAGE immunoblotting, and inhibition studies of these assays were performed. Proteins were quantified by enzyme-immunoassay. Eleven probiotics were studied. No label advertised about egg content, eight labels warned about lactose, lactic acid or cow's milk, one label claimed to be milk-free, and two gave no information. Cow's milk proteins were detected, by at least one lab technique, in 10/11 probiotics, three over 2.5 mg/kg (21, 52, 112 mg/kg). Hen's egg white proteins were detected in 3/11 probiotics, only one had more than 2.5 mg/kg (47 mg/kg). Probiotic compounds may contain hidden allergens of food and may not be safe for subjects with allergy to cow's milk or hen's egg. © 2012 John Wiley & Sons A/S.

  15. Density distributions and depth in flocks

    Science.gov (United States)

    Lewis, J. M.; Turner, M. S.

    2017-12-01

    Recent experimental evidence suggests that interactions in flocks of birds do not involve a characteristic length scale. Bird flocks have also been revealed to have an inhomogeneous density distribution, with the density of birds near the border greater than near the centre. We introduce a strictly metric-free model for collective behaviour that incorporates a distributed motional bias, providing control of the density distribution. A simple version of this model is then able to provide a good fit to published data for the density variation across flocks of Starlings. We find that it is necessary for individuals on the edge of the flock to have an inward motional bias but that birds in the interior of the flock instead must have an outward bias. We discuss the ability of individuals to determine their depth within a flock and show how this might be achieved by relatively simple analysis of their visual environment.

  16. Flocking regimes in a simple lattice model.

    Science.gov (United States)

    Raymond, J R; Evans, M R

    2006-03-01

    We study a one-dimensional lattice flocking model incorporating all three of the flocking criteria proposed by Reynolds [Computer Graphics 21, 4 (1987)]: alignment, centering, and separation. The model generalizes that introduced by O. J. O'Loan and M. R. Evans [J. Phys. A. 32, L99 (1999)]. We motivate the dynamical rules by microscopic sampling considerations. The model exhibits various flocking regimes: the alternating flock, the homogeneous flock, and dipole structures. We investigate these regimes numerically and within a continuum mean-field theory.

  17. Use of fly screens to reduce Campylobacter spp. introduction in broiler houses

    DEFF Research Database (Denmark)

    Hald, Birthe; Sommer, Helle Mølgaard; Skovgaard, Henrik

    2007-01-01

    Fly screens that prevented influx of flies in 20 broiler houses during the summer of 2006 in Denmark caused a decrease in Campylobacter spp.–positive flocks from 51.4% in control houses to 15.4% in case houses. A proportional reduction in the incidence of chicken-borne campylobacteriosis can...

  18. Flocking through disorder

    Science.gov (United States)

    Morin, Alexandre; Desreumaux, Nicolas; Caussin, Jean-Baptiste; Bartolo, Denis

    How do flocks, herds and swarms proceed through disordered environments? This question is not only crucial to animal groups in the wild, but also to virtually all applications of collective robotics, and active materials composed of synthetic motile units. In stark contrast, appart from very rare exceptions, our physical understanding of flocking has been hitherto limited to homogeneous media. Here we explain how collective motion survives to geometrical disorder. To do so, we combine experiments on motile colloids cruising through random microfabricated obstacles, and analytical theory. We explain how disorder and bending elasticity compete to channel the flow of polar flocks along sparse river networks akin those found beyond plastic depinning in driven condensed matter. Further increasing disorder, we demonstrate that collective motion is suppressed in the form of a first-order phase transition generic to all polar active materials.

  19. An index for quantifying flocking behavior.

    Science.gov (United States)

    Quera, Vicenç; Herrando, Salvador; Beltran, Francesc S; Salas, Laura; Miñano, Meritxell

    2007-12-01

    One of the classic research topics in adaptive behavior is the collective displacement of groups of organisms such as flocks of birds, schools of fish, herds of mammals, and crowds of people. However, most agent-based simulations of group behavior do not provide a quantitative index for determining the point at which the flock emerges. An index was developed of the aggregation of moving individuals in a flock and an example was provided of how it can be used to quantify the degree to which a group of moving individuals actually forms a flock.

  20. Design of Connectivity Preserving Flocking Using Control Lyapunov Function

    Directory of Open Access Journals (Sweden)

    Bayu Erfianto

    2016-01-01

    Full Text Available This paper investigates cooperative flocking control design with connectivity preserving mechanism. During flocking, interagent distance is measured to determine communication topology of the flocks. Then, cooperative flocking motion is built based on cooperative artificial potential field with connectivity preserving mechanism to achieve the common flocking objective. The flocking control input is then obtained by deriving cooperative artificial potential field using control Lyapunov function. As a result, we prove that our flocking protocol establishes group stabilization and the communication topology of multiagent flocking is always connected.

  1. A Flocking Based algorithm for Document Clustering Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Xiaohui [ORNL; Gao, Jinzhu [ORNL; Potok, Thomas E [ORNL

    2006-01-01

    Social animals or insects in nature often exhibit a form of emergent collective behavior known as flocking. In this paper, we present a novel Flocking based approach for document clustering analysis. Our Flocking clustering algorithm uses stochastic and heuristic principles discovered from observing bird flocks or fish schools. Unlike other partition clustering algorithm such as K-means, the Flocking based algorithm does not require initial partitional seeds. The algorithm generates a clustering of a given set of data through the embedding of the high-dimensional data items on a two-dimensional grid for easy clustering result retrieval and visualization. Inspired by the self-organized behavior of bird flocks, we represent each document object with a flock boid. The simple local rules followed by each flock boid result in the entire document flock generating complex global behaviors, which eventually result in a clustering of the documents. We evaluate the efficiency of our algorithm with both a synthetic dataset and a real document collection that includes 100 news articles collected from the Internet. Our results show that the Flocking clustering algorithm achieves better performance compared to the K- means and the Ant clustering algorithm for real document clustering.

  2. Design of Connectivity Preserving Flocking Using Control Lyapunov Function

    OpenAIRE

    Erfianto, Bayu; Bambang, Riyanto T.; Hindersah, Hilwadi; Muchtadi-Alamsyah, Intan

    2016-01-01

    This paper investigates cooperative flocking control design with connectivity preserving mechanism. During flocking, interagent distance is measured to determine communication topology of the flocks. Then, cooperative flocking motion is built based on cooperative artificial potential field with connectivity preserving mechanism to achieve the common flocking objective. The flocking control input is then obtained by deriving cooperative artificial potential field using control Lyapunov functio...

  3. Carbon Dioxide and Nitrogen Infused Compressed Air Foam for Depopulation of Caged Laying Hens

    Science.gov (United States)

    Gurung, Shailesh; White, Dima; Archer, Gregory; Styles, Darrel; Zhao, Dan; Farnell, Yuhua; Byrd, James; Farnell, Morgan

    2018-01-01

    Simple Summary Compressed air, detergent, and water make up compressed air foam. Our laboratory has previously reported that compressed air foam may be an effective method for mass depopulation of caged layer hens. Gases, such as carbon dioxide and nitrogen, have also been used for poultry euthanasia and depopulation. The objective of this study was to produce compressed air foam infused with carbon dioxide or nitrogen to compare its efficacy against foam with air and gas inhalation methods (carbon dioxide or nitrogen) for depopulation of caged laying hens. The study showed that a carbon dioxide-air mixture or 100% nitrogen can replace air to make compressed air foam. However, the foam with carbon dioxide had poor foam quality compared to the foam with air or nitrogen. The physiological stress response of hens subjected to foam treatments with and without gas infusion did not differ significantly. Hens exposed to foam with nitrogen died earlier as compared to methods such as foam with air and carbon dioxide. The authors conclude that infusion of nitrogen into compressed air foam results in better foam quality and shortened time to death as compared to the addition of carbon dioxide. Abstract Depopulation of infected poultry flocks is a key strategy to control and contain reportable diseases. Water-based foam, carbon dioxide inhalation, and ventilation shutdown are depopulation methods available to the poultry industry. Unfortunately, these methods have limited usage in caged layer hen operations. Personnel safety and welfare of birds are equally important factors to consider during emergency depopulation procedures. We have previously reported that compressed air foam (CAF) is an alternative method for depopulation of caged layer hens. We hypothesized that infusion of gases, such as carbon dioxide (CO2) and nitrogen (N2), into the CAF would reduce physiological stress and shorten time to cessation of movement. The study had six treatments, namely a negative control

  4. Changes in position and quality of preferred nest box: effects on nest box use by laying hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch; Nielsen, Birte L.

    2013-01-01

    Using laying hens, we investigated whether position of a nest box, both within the pen and relative to other nest boxes, influenced the preference for a nest box, and how a sudden and marked change to the preferred box influenced the use of nest boxes by the hens. Groups (n=12) of 15 Isa Warren...... hens were housed in pens, each with five identical nest boxes in different positions: Two single (in a corner or not) and a triplet of nest boxes (one of which in a corner). The use of nest boxes was determined by the number of eggs laid daily in each box. Three experiments, each lasting 10 days, were...... carried out. First, the undisturbed use of each of the nest box types was investigated, and a strong preference (Peggs laid there. Second, each of the hen groups was moved to another pen allocated at random, and where...

  5. Comparative study on immunoglobulin Y transfer from breeding hens to egg yolk and progeny chicks in different breeds of poultry

    Directory of Open Access Journals (Sweden)

    Ritu Agrawal

    2016-04-01

    Full Text Available Aim: This study was undertaken to compare the immunoglobulin Y (IgY level and its efficacy in laying hens of four different breeds of poultry (viz.,Vanraja, Gramapriya, BlackRock, and KalingaBrown and its relative transfer in egg yolk and chick. Materials and Methods: This study was conducted in 48 apparently healthy laying hens vaccinated with Salmonella inactivated polyvalent vaccine, eggs and progeny chicks; 12 each from four different breeds of poultry,viz.,Vanraja, Gramapriya, BlackRock, and KalingaBrown. The methodology included measurement of egg and yolk weight, total protein and IgY in egg yolk, total serum protein and IgY in breeding hens, and progeny chicks and extent of IgY transfer from hens to yolk then to chicks. Further, Salmonella-specific antibodies in breeding hens, egg yolk and progeny chicks were assessed using O and H antigen by tube agglutination test. Results: The egg weight differed nonsignificantly (p>0.05 among breeds, however, breed wise significant variation (p0.05 difference among breed was found in total protein of egg yolk and chick. The IgY concentration in hens, egg yolk and chick was found to be in the range of 5.35±0.63- 5.83±0.65, 2.3±0.1-2.6±0.2, and 1.3±0.11-1.7±0.16 mg/ml, respectively which is uniform and independent of total protein concentration at all the three levels. Significant breed variations were not observed in maternal IgY transfer from breeding hens to chicks and were 25.62±1.42-36.06±4.34% of total IgY in parent flock. Moderate to higher rate of seroprevalence with peak titers of 1:640 against Salmonella-specific antibodies was observed in only 41.6% of breeding hens. Conclusion: No significant difference in the rate of transfer of IgY was observed in four breeds studied (viz.,Vanraja, Gramapriya, BlackRock, and KalingaBrown and moderate seropositivity was detected for Salmonella-specific antibodies in progeny chicks.

  6. Statistical mechanics for natural flocks of birds

    Science.gov (United States)

    Bialek, William; Cavagna, Andrea; Giardina, Irene; Mora, Thierry; Silvestri, Edmondo; Viale, Massimiliano; Walczak, Aleksandra M.

    2012-01-01

    Flocking is a typical example of emergent collective behavior, where interactions between individuals produce collective patterns on the large scale. Here we show how a quantitative microscopic theory for directional ordering in a flock can be derived directly from field data. We construct the minimally structured (maximum entropy) model consistent with experimental correlations in large flocks of starlings. The maximum entropy model shows that local, pairwise interactions between birds are sufficient to correctly predict the propagation of order throughout entire flocks of starlings, with no free parameters. We also find that the number of interacting neighbors is independent of flock density, confirming that interactions are ruled by topological rather than metric distance. Finally, by comparing flocks of different sizes, the model correctly accounts for the observed scale invariance of long-range correlations among the fluctuations in flight direction. PMID:22427355

  7. Development of a Machine Vision Method for the Monitoring of Laying Hens and Detection of Multiple Nest Occupations

    Directory of Open Access Journals (Sweden)

    Mauro Zaninelli

    2018-01-01

    Full Text Available Free range systems can improve the welfare of laying hens. However, the access to environmental resources can be partially limited by social interactions, feeding of hens, and productivity, can be not stable and damaging behaviors, or negative events, can be observed more frequently than in conventional housing systems. In order to reach a real improvement of the hens’ welfare the study of their laying performances and behaviors is necessary. With this purpose, many systems have been developed. However, most of them do not detect a multiple occupation of the nest negatively affecting the accuracy of data collected. To overcome this issue, a new “nest-usage-sensor” was developed and tested. It was based on the evaluation of thermografic images, as acquired by a thermo-camera, and the performing of patter recognitions on images acquired from the nest interior. The sensor was setup with a “Multiple Nest Occupation Threshold” of 796 colored pixels and a template of triangular shape and sizes of 43 × 33 pixels (high per base. It was tested through an experimental nesting system where 10 hens were reared for a month. Results showed that the evaluation of thermografic images could increase the detection performance of a multiple occupation of the nest and to apply an image pattern recognition technique could allow for counting the number of hens in the nest in case of a multiple occupation. As a consequence, the accuracy of data collected in studies on laying performances and behaviors of hens, reared in a free-range housing system, could result to be improved.

  8. Free range hens use the range more when the outdoor environment is enriched.

    Science.gov (United States)

    Nagle, T A D; Glatz, P C

    2012-04-01

    To evaluate the role of using forage, shade and shelterbelts in attracting birds into the range, three trials were undertaken with free range layers both on a research facility and on commercial farms. Each of the trials on the free range research facility in South Australia used a total of 120 laying hens (Hyline Brown). Birds were housed in an eco-shelter which had 6 internal pens of equal size with a free range area adjoining the shelter. The on-farm trials were undertaken on commercial free range layer farms in the Darling Downs in Southeast Queensland with bird numbers on farms ranging from 2,000-6,800 hens. The first research trial examined the role of shaded areas in the range; the second trial examined the role of forage and the third trial examined the influence of shelterbelts in the range. These treatments were compared to a free range area with no enrichment. Aggressive feather pecking was only observed on a few occasions in all of the trials due to the low bird numbers housed. Enriching the free range environment attracted more birds into the range. Shaded areas were used by 18% of the hens with a tendency (p = 0.07) for more hens to be in the paddock. When forage was provided in paddocks more control birds (55%) were observed in the range in morning than in the afternoon (30%) while for the forage treatments 45% of the birds were in the range both during the morning and afternoon. When shelterbelts were provided there was a significantly (prange (43% vs. 24%) and greater numbers of birds were observed in areas further away from the poultry house. The results from the on-farm trials mirrored the research trials. Overall 3 times more hens used the shaded areas than the non shaded areas, with slightly more using the shade in the morning than in the afternoon. As the environmental temperature increased the number of birds using the outdoor shade also increased. Overall 17 times more hens used the shelterbelt areas than the control areas, with slightly

  9. Free Range Hens Use the Range More When the Outdoor Environment Is Enriched

    Directory of Open Access Journals (Sweden)

    T. A. D. Nagle

    2012-04-01

    Full Text Available To evaluate the role of using forage, shade and shelterbelts in attracting birds into the range, three trials were undertaken with free range layers both on a research facility and on commercial farms. Each of the trials on the free range research facility in South Australia used a total of 120 laying hens (Hyline Brown. Birds were housed in an eco-shelter which had 6 internal pens of equal size with a free range area adjoining the shelter. The on-farm trials were undertaken on commercial free range layer farms in the Darling Downs in Southeast Queensland with bird numbers on farms ranging from 2,000–6,800 hens. The first research trial examined the role of shaded areas in the range; the second trial examined the role of forage and the third trial examined the influence of shelterbelts in the range. These treatments were compared to a free range area with no enrichment. Aggressive feather pecking was only observed on a few occasions in all of the trials due to the low bird numbers housed. Enriching the free range environment attracted more birds into the range. Shaded areas were used by 18% of the hens with a tendency (p = 0.07 for more hens to be in the paddock. When forage was provided in paddocks more control birds (55% were observed in the range in morning than in the afternoon (30% while for the forage treatments 45% of the birds were in the range both during the morning and afternoon. When shelterbelts were provided there was a significantly (p<0.05 higher % of birds in the range (43% vs. 24% and greater numbers of birds were observed in areas further away from the poultry house. The results from the on-farm trials mirrored the research trials. Overall 3 times more hens used the shaded areas than the non shaded areas, with slightly more using the shade in the morning than in the afternoon. As the environmental temperature increased the number of birds using the outdoor shade also increased. Overall 17 times more hens used the shelterbelt

  10. Survey of the traditional poultry production system in the Bamenda area, Cameroon

    International Nuclear Information System (INIS)

    Ekue, F.N.; Pone, K.D.; Mafeni, M.J.; Nfi, A.N.; Njoya, J.

    2002-01-01

    A study of the traditional poultry production system in the Bamenda area in Cameroon was conducted using a baseline survey covering the rainy and dry seasons from December, 1999-June, 2000. This survey focused mainly on the characterization of the flock size and structure, housing system, feeding, marketing of chickens, health, flock breeding and ownership patterns. The results showed that among poultry species surveyed, chickens predominated in all households, followed by ducks (15.4%) and pigeons (7.7%). A cock had access to about 2-3 hens and one hen had a brood of 1-3 chicks at a time with an overall higher hen/cock and chicks/hen ratio for the dry season. Production and reproduction performance results showed that hens laid about 3 clutches of 12 eggs per year and this was similar for both seasons. The most predominant disease symptoms in descending order of importance included diarrhoea, coughing and ectoparasitism. Although the overall disease occurrence rate was high in growers, chicks suffered from many unclassified ailments. From the survey results, ethno-veterinary therapy featured as the most frequent method of treating diseases in rural poultry in the Bamenda area. With regard to flock ownership and management patterns, the survey results showed that women owned birds in the majority of the cases (38.5%) followed by men (23.1%) and children (15.3%). Although all gender categories were involved in village chicken management, the greatest participation came from women, followed by men, children and the family as a whole. Construction of shelters was mainly a job for the men with assistance from the children. Women were mostly involved in providing water to the birds, preparing supplementation rations and selling eggs. Finally, with regard to household decision making on issues related to poultry management, men played the leading role (66.7%), followed by women (28.4%) and then children (3.7%). (author)

  11. Compliance/non-compliance with biosecurity rules specified in the Danish Quality Assurance system (KIK) and Campylobacter-positive broiler flocks 2012 and 2013.

    Science.gov (United States)

    Sandberg, M; Dahl, J; Lindegaard, L L; Pedersen, J R

    2017-01-01

    One source for Campylobacter jejuni infections in humans could be consumption of broiler meat. Transmission of Campylobacter into broiler houses/flocks occurs via many routes. A number of biosecurity rules is specified in the Quality Assurance System in Danish Chicken Production (KIK) - for which the broiler producers annually are audited for compliance with, by bureau Veritas. Multivariable logistic regression models were used to investigated the association between Compliance/non-compliance with biosecurity rules and Campylobacter-positive flocks - on KIK data from 2012 and 2013. Month and before after audit period were also included in the models. KIK rules important to comply with were: no vegetation around houses, closed systems for feed storage and distribution, and division between clean and unclean zones within broiler houses. A Campylobacter-reducing effect was observed of audit visits (in itself), indicating that there is more focus on compliance with KIK at the time of an audit visit, and that adequate daily biosecurity behavior is important. © 2016 Poultry Science Association Inc.

  12. The effect of keel fractures on egg production, feed and water consumption in individual laying hens.

    Science.gov (United States)

    Nasr, M A F; Murrell, J; Nicol, C J

    2013-01-01

    The impact of keel bone fractures on egg production, egg weight and feed and water consumption in individual laying hens. A total of 165 Lohmann brown laying hens were obtained from a commercial farm that consisted of 105 with keel fractures and 60 without keel fractures. 2. After a 4-d period of acclimatisation, hens were individually housed and provided with ad libitum food and water for a 24-h period. The number of eggs laid, egg weight, feed and water consumption during this period were recorded. Keel bone strength was also assessed. 3. Hens free from keel fractures laid more eggs (91.7% vs. 84.9%) of significantly heavier weight (61.9 g vs. 60.2 g), ate less feed (139 g vs. 151 g) and drank less water (212 ml vs. 237 ml) than hens with fractures. 4. There was a significant positive association between keel fracture severity and water consumption, and a significant negative association between keel fracture severity and egg weight and keel bone strength. 5. This small-scale study on individual birds shows that keel bone fractures may have an impact on the economics of egg production.

  13. Retention of Campylobacter (Campylobacterales: Campylobacteraceae) in the House Fly (Diptera: Muscidae)

    DEFF Research Database (Denmark)

    Skovgard, H.; Kristensen, K.; Hald, Birthe

    2011-01-01

    The house fly (Musca domestica L.) may transmit Campylobacter to broiler flocks. We assessed the retention lime of house flies for Campylobacter jejuni at five temperatures and three doses. Flies were inoculated individually at their proboscis with 1.6 x 10(7) CFU (colony forming units) of C...

  14. Influence of flock coating on bending rigidity of woven fabrics

    Science.gov (United States)

    Ozdemir, O.; Kesimci, M. O.

    2017-10-01

    This work presents the preliminary results of our efforts that focused on the effect of the flock coating on the bending rigidity of woven fabrics. For this objective, a laboratory scale flocking unit is designed and flocked samples of controlled flock density are produced. Bending rigidity of the samples with different flock densities are measured on both flocked and unflocked sides. It is shown that the bending rigidity depends on both flock density and whether the side to be measured is flocked or not. Adhesive layer thickness on the bending rigidity is shown to be dramatic. And at higher basis weights, flock density gets less effective on bending rigidity.

  15. Research on an Infectious Disease Transmission by Flocking Birds

    Directory of Open Access Journals (Sweden)

    Mingsheng Tang

    2013-01-01

    Full Text Available The swarm intelligence is becoming a hot topic. The flocking of birds is a natural phenomenon, which is formed and organized without central or external controls for some benefits (e.g., reduction of energy consummation. However, the flocking also has some negative effects on the human, as the infectious disease H7N9 will easily be transmited from the denser flocking birds to the human. Zombie-city model has been proposed to help analyzing and modeling the flocking birds and the artificial society. This paper focuses on the H7N9 virus transmission in the flocking birds and from the flocking birds to the human. And some interesting results have been shown: (1 only some simple rules could result in an emergence such as the flocking; (2 the minimum distance between birds could affect H7N9 virus transmission in the flocking birds and even affect the virus transmissions from the flocking birds to the human.

  16. Research on an infectious disease transmission by flocking birds.

    Science.gov (United States)

    Tang, Mingsheng; Mao, Xinjun; Guessoum, Zahia

    2013-01-01

    The swarm intelligence is becoming a hot topic. The flocking of birds is a natural phenomenon, which is formed and organized without central or external controls for some benefits (e.g., reduction of energy consummation). However, the flocking also has some negative effects on the human, as the infectious disease H7N9 will easily be transmited from the denser flocking birds to the human. Zombie-city model has been proposed to help analyzing and modeling the flocking birds and the artificial society. This paper focuses on the H7N9 virus transmission in the flocking birds and from the flocking birds to the human. And some interesting results have been shown: (1) only some simple rules could result in an emergence such as the flocking; (2) the minimum distance between birds could affect H7N9 virus transmission in the flocking birds and even affect the virus transmissions from the flocking birds to the human.

  17. Preliminary evaluation of a nest usage sensor to detect double nest occupations of laying hens.

    Science.gov (United States)

    Zaninelli, Mauro; Costa, Annamaria; Tangorra, Francesco Maria; Rossi, Luciana; Agazzi, Alessandro; Savoini, Giovanni

    2015-01-26

    Conventional cage systems will be replaced by housing systems that allow hens to move freely. These systems may improve hens' welfare, but they lead to some disadvantages: disease, bone fractures, cannibalism, piling and lower egg production. New selection criteria for existing commercial strains should be identified considering individual data about laying performance and the behavior of hens. Many recording systems have been developed to collect these data. However, the management of double nest occupations remains critical for the correct egg-to-hen assignment. To limit such events, most systems adopt specific trap devices and additional mechanical components. Others, instead, only prevent these occurrences by narrowing the nest, without any detection and management. The aim of this study was to develop and test a nest usage "sensor", based on imaging analysis, that is able to automatically detect a double nest occupation. Results showed that the developed sensor correctly identified the double nest occupation occurrences. Therefore, the imaging analysis resulted in being a useful solution that could simplify the nest construction for this type of recording system, allowing the collection of more precise and accurate data, since double nest occupations would be managed and the normal laying behavior of hens would not be discouraged by the presence of the trap devices.

  18. Comparison of Domestic and Foreign Commercial Brown Layer Hens in Terms of Yield Characteristics in Free-Range Raising System

    Directory of Open Access Journals (Sweden)

    İsmail Türker

    2017-07-01

    Full Text Available This research was carried out under producer conditions to determine the appropriate hen material to be used in the free range laying system. For this purpose, the foreign brown commercial layer genotype which coded YB and native brown egg layer Atak-S genotype was compared in terms of yield and egg quality characteristics. This study included 150 hens from each genotype and a total of 300 chickens were used. Each genotype divided into three groups among themselves and 50 hens were raised each group. In the poultry house with deep-litter ground system, 5 chickens were raised in the unit area (m2 and, 4 m2 grazing area was allocated per each hen in the grazing area. The pullets that hatched on the same day were obtained from a commercial firm at 16 weeks of age. The study was carried out until 80 weeks of age. Egg yield and egg quality characteristics were determined during this period. There was no difference between the genotypes in terms of 50% egg yield age, egg weight, hen-day egg yield, hen-house egg yield, viability, albumen index, yolk index, haugh unit and yolk color. In contrast, the difference between the genotypes was found to be important in terms of body weight at weeks of 18th and 80th age, feed consumption, feed conversation ratio, shape index, shell thickness, density, meat-blood spot ratio and egg shell color. In this study, genotypes were not superior to each other in terms of all traits. However, as a result of the economic analyzes made in consideration of market conditions and observations made in terms of animal sensitivities, it was concluded that the Atak-S genotype was more suitable for free-range egg production system.

  19. A simple mathematical method to estimate ammonia emission from in-house windrowing of poultry litter.

    Science.gov (United States)

    Ro, Kyoung S; Szogi, Ariel A; Moore, Philip A

    2018-05-12

    In-house windrowing between flocks is an emerging sanitary management practice to partially disinfect the built-up litter in broiler houses. However, this practice may also increase ammonia (NH 3 ) emission from the litter due to the increase in litter temperature. The objectives of this study were to develop mathematical models to estimate NH 3 emission rates from broiler houses practicing in-house windrowing between flocks. Equations to estimate mass-transfer areas form different shapes windrowed litter (triangular, rectangular, and semi-cylindrical prisms) were developed. Using these equations, the heights of windrows yielding the smallest mass-transfer area were estimated. Smaller mass-transfer area is preferred as it reduces both emission rates and heat loss. The heights yielding the minimum mass-transfer area were 0.8 and 0.5 m for triangular and rectangular windrows, respectively. Only one height (0.6 m) was theoretically possible for semi-cylindrical windrows because the base and the height were not independent. Mass-transfer areas were integrated with published process-based mathematical models to estimate the total house NH 3 emission rates during in-house windrowing of poultry litter. The NH 3 emission rate change calculated from the integrated model compared well with the observed values except for the very high NH 3 initial emission rate from mechanically disturbing the litter to form the windrows. This approach can be used to conveniently estimate broiler house NH 3 emission rates during in-house windrowing between flocks by simply measuring litter temperatures.

  20. Ammonia and nitrous oxide emissions from broiler houses with downtime windrowed litter

    Science.gov (United States)

    An emerging poultry manure management practice is in house windrowing to disinfect the litter. With this practice, growers windrow the litter in broiler houses between flocks, usually for 2 weeks. This results in high litter temperatures that can reduce pathogens in the litter. However, this practi...

  1. The novel object test as predictor of feather damage in cage-housed Rhode Island Red and White Leghorn laying hens

    NARCIS (Netherlands)

    Uitdehaag, K.A.; Komen, J.; Rodenburg, T.B.; Kemp, B.; Arendonk, van J.A.M.

    2008-01-01

    The propensity to develop feather pecking (FP) has a genetic component and has been related to fear responses in laying hens. A convenient test measuring the fear response might therefore be used to identify hens with a stronger propensity to develop FP. However, genetic origin and age can influence

  2. Reduced flocking by birds on islands with relaxed predation.

    Science.gov (United States)

    Beauchamp, Guy

    2004-05-22

    Adaptive hypotheses for the evolution of flocking in birds have usually focused on predation avoidance or foraging enhancement. It still remains unclear to what extent each factor has contributed to the evolution of flocking. If predation avoidance were the sole factor involved, flocking should not be prevalent when predation is relaxed. I examined flocking tendencies along with mean and maximum flock size in species living on islands where predation risk is either absent or negligible and then compared these results with matched counterparts on the mainland. The dataset consisted of 46 pairs of species from 22 different islands across the world. The tendency to flock was retained on islands in most species, but in pairs with dissimilar flocking tendencies, island species were less likely to flock. Mean and maximum flock size were smaller on islands than on the mainland. Potential confounding factors such as population density, nest predation, habitat type, food type and body mass failed to account for the results. The results suggest that predation is a significant factor in the evolution of flocking in birds. Nevertheless, predation and other factors, such as foraging enhancement, probably act together to maintain the trait in most species.

  3. How does the presence of excreta affect the behavior of laying hens on scratch pads?

    Science.gov (United States)

    Pokharel, B B; Boecker, I; Kwon, I Y; Jeyachanthiran, L; McBride, P; Harlander-Matauschek, A

    2018-03-01

    Enriched cages for laying hens provide scratch pads for foraging on the wire mesh floors. Apart from foraging on scratch pads, hens also defecate on these pads, causing them to become soiled with excreta. This study was conducted to determine the relative preference of laying hens for foraging on clean (C) scratch pads or scratch pads soiled with excreta (E), and to study the behaviors performed by hens on such pads. A total of 288 laying hens was housed in 16 enriched cages (18 hens/cage), each divided into 2 compartments. On a daily basis, half of the scratch pads (one in each compartment) were removed and cleaned, while the other half were cleaned and then covered with 550 g (0.35 g/cm2) of conspecific excreta. The C and E scratch pads were then put back into the cages in a systematic order to avoid side bias. Feed was delivered automatically onto the scratch pads as a litter substrate. The frequency of visits and the total time spent performing different behaviors on C and E pads were video-recorded [the time of video recording was relative to litter (feed) delivery on the scratch pads] for a total of 10 min/d, 3 times/wk, over a period of 4 weeks. Overall, the allocation of the time budget for different behaviors was found to be-in order of greatest to least amount of time-resting, locomotor behaviors (walking and running), foraging, and dust bathing. Laying hens showed a relative preference for E scratch pads by visiting them more frequently (P = 0.001), and spent more time (P = 0.035) foraging on them, whereas they rested for more time (P hens. Similarly, the longer use of C scratch pads for resting indicates the need for an ideal and clean resting surface in enriched cages.

  4. A discontinuous Galerkin method on kinetic flocking models

    OpenAIRE

    Tan, Changhui

    2014-01-01

    We study kinetic representations of flocking models. They arise from agent-based models for self-organized dynamics, such as Cucker-Smale and Motsch-Tadmor models. We prove flocking behavior for the kinetic descriptions of flocking systems, which indicates a concentration in velocity variable in infinite time. We propose a discontinuous Galerkin method to treat the asymptotic $\\delta$-singularity, and construct high order positive preserving scheme to solve kinetic flocking systems.

  5. Self-Organized Fission Control for Flocking System

    Directory of Open Access Journals (Sweden)

    Mingyong Liu

    2015-01-01

    Full Text Available This paper studies the self-organized fission control problem for flocking system. Motivated by the fission behavior of biological flocks, information coupling degree (ICD is firstly designed to represent the interaction intensity between individuals. Then, from the information transfer perspective, a “maximum-ICD” based pairwise interaction rule is proposed to realize the directional information propagation within the flock. Together with the “separation/alignment/cohesion” rules, a self-organized fission control algorithm is established that achieves the spontaneous splitting of flocking system under conflict external stimuli. Finally, numerical simulations are provided to demonstrate the effectiveness of the proposed algorithm.

  6. Oral immunisation of laying hens with the live vaccine strains of TAD Salmonella vac E and TAD Salmonella vac T reduces internal egg contamination with Salmonella Enteritidis.

    Science.gov (United States)

    Gantois, Inne; Ducatelle, Richard; Timbermont, Leen; Boyen, Filip; Bohez, Lotte; Haesebrouck, Freddy; Pasmans, Frank; van Immerseel, Filip

    2006-09-11

    Eggs are a major source of human infections with Salmonella. Therefore controlling egg contamination in laying hen flocks is one of the main targets for control programmes. A study was carried out to assess the effect of oral vaccination with TAD Salmonella vac E, TAD Salmonella vac T and with both vaccines TAD Salmonella vac E and TAD Salmonella vac T, on colonization of the reproductive tract and internal egg contamination of laying hens with Salmonella Enteritidis. Three groups of 30 laying hens were vaccinated at 1 day, 6 weeks and 16 weeks of age with either one of the vaccine strains, or a combination of both vaccine strains, while a fourth group was left unvaccinated. At 24 weeks of age, the birds were intravenously challenged with 0.5 ml containing 5 x 10(7)cfu Salmonella Enteritidis PT4 S1400/94. The number of oviducts from which Salmonella was isolated, was significantly lower in the vaccinated than in the non-vaccinated hens at 3 weeks post-challenge. Significantly less egg contents were Salmonella positive in the birds vaccinated with TAD Salmonella vac E or TAD Salmonella vac T (12/105 batches of eggs in both groups) than in the unvaccinated birds (28/105 batches of eggs). Internal egg contamination in the hens vaccinated with both TAD Salmonella vac E and TAD Salmonella vac T was even more reduced, as over the whole experiment, only one batch of eggs was positive. In conclusion, these data indicate that vaccination of laying hens with these live vaccines could be considered as a valuable tool in controlling internal egg contamination.

  7. Accumulation of dioxins and PCB in house fly larvae (musca domestica) reared in poultry manure and used in feed for organic laying hens

    DEFF Research Database (Denmark)

    Nordentoft, Steen; Cederberg, Tommy Licht; Fischer, Christian Holst

    2014-01-01

    higher content of the persistent organic environmental contaminants dioxins and PCB than eggs from conventional hens held indoor in cages. 1,2 The elevated levels of dioxins and PCB are most likely due to the hens picking in soils contaminated by industrial activities, burning of waste, chemical spillage...... etc. As manure from free range hens is expected to have elevated contents of dioxins and PCB, we investigated whether larvae reared in this type of manure accumulate dioxins and PCB, and if feeding organic laying hens with these larvae would increase the levels of dioxins and PCB in the hen eggs...... larvae, poultry manure, compost and compound feed as well as pooled egg samples from each group were analysed for levels of dioxins and PCB. Analytical procedure: after extraction of the sample with a mixture of pentane and acetone (88:12), the extracts were cleaned-up on a multilayer silica column...

  8. Model-predicted ammonia emission from two broiler houses with different rearing systems

    Directory of Open Access Journals (Sweden)

    Nilsa Duarte Silva Lima

    2015-10-01

    Full Text Available Ammonia (NH3 emissions from broiler production can affect human and animal health and may cause acidification and eutrophication of the surrounding environment. This study aimed to estimate ammonia emissions from broiler litter in two systems of forced ventilation, the tunnel ventilation (TV and the dark house (DH. The experiment was carried out on eight commercial broiler houses, and the age of the birds (day, d, pH and litter temperature were recorded. Broilers were reared on built-up wood shaving litter using an average flock density of 14 bird m–2. Temperature and relative humidity inside the broiler houses were recorded in the morning during the grow-out period. A factorial experimental design was adopted, with two types of houses, four replicates and two flocks with two replicates each. A deterministic model was used to predict ammonia emissions using the litter pH and temperature, and the day of grow-out. The highest litter temperature and pH were found at 42 d of growth in both housing systems. Mean ambient air temperature and relative humidity did not differ in either system. Mean model predicted ammonia emission was higher in the DH rearing system (5200 mg NH3 m−2h−1 at 42 d than in the TV system (2700 mg NH3m−2 h−1 at 42 d. TV presented the lowest mean litter temperature and pH at 42 d of growth. In the last week of the broilers’ grow-out cycle, estimated ammonia emissions inside DH reached 5700 mg m−2h−1 in one of the flocks. Ammonia emissions were higher inside DH, and they did not differ between flocks. Assuming a broiler market weight in Brazil of close to 2 kg, ammonia emissions were equivalent to 12 g NH3 bird-marketed−1. Model-predicted ammonia emissions provided comprehensible estimations and might be used in abatement strategies for NH3 emission.

  9. Comparison between Laying Hen Performance in the Cage System and the Deep Litter System on a Diet Free from Animal Protein

    Directory of Open Access Journals (Sweden)

    E. Voslářová

    2006-01-01

    Full Text Available Battery cage systems for housing laying hens are being replaced by alternative systems including the deep litter system. At the same time, the substitution of meat and bone meal by vegetable matter in poultry feed mixtures is sought in the nutrition of laying hens. In the experiment, we compared the performance of laying hens of the ISA BROWN hybrid in both the cage system and the deep litter system, on a diet with the meat and bone meal content replaced by vegetable feeds (based on lupin. In the first group, 36 laying hens were kept in the deep litter system; in the second group, 36 laying hens were kept in cages. Over the period of nine months, the number of eggs laid, their weight, shell quality, the clinical state of the laying hens and incidence of their mortality were monitored daily. We found that in the cage system a higher number of eggs was obtained; a lower mean egg weight (p p p p p > 0.05, and the number of laying hens which died was lower (p < 0.05 in comparison with the deep litter system. The results of the experiment demonstrate that, with the substitution of meat and bone meal by vegetable matter in the feed mixtures for laying hens, there are differences between the performance of laying hens from the deep litter system as compared to the laying hens from the cage system. The deep litter system better meets the requirements for the welfare of laying hens; however, it provides a lower yield.

  10. From particle to kinetic and hydrodynamic descriptions of flocking

    OpenAIRE

    Ha, Seung-Yeal; Tadmor, Eitan

    2008-01-01

    We discuss the Cucker-Smale's (C-S) particle model for flocking, deriving precise conditions for flocking to occur when pairwise interactions are sufficiently strong long range. We then derive a Vlasov-type kinetic model for the C-S particle model and prove it exhibits time-asymptotic flocking behavior for arbitrary compactly supported initial data. Finally, we introduce a hydrodynamic description of flocking based on the C-S Vlasov-type kinetic model and prove flocking behavior \\emph{without...

  11. Epidemiology of Mycoplasma agalactiae and Mycoplasma mycoides cluster in flocks of northeastern Brazil

    Directory of Open Access Journals (Sweden)

    Sandra Batista dos Santos

    2018-04-01

    Full Text Available ABSTRACT: The present study aimed to investigate contagious agalactia (CA in flocks from Pernambuco State. The study involved 225 goats and 63 ewes; 288 milk samples and 100 vaginal swabs were collected in total. The PCR assays were carried out using specific primers to Mycoplasma agalactiae and the Mycoplasma mycoides cluster. Among the goat’s milk samples,12.0% (27/225 were positive for Mycoplasma agalactiae DNA, while 5.3% (12/225 contained the Mycoplasma mycoides cluster. Of the vaginal swabs taken from goats, 15.4% (12/78 were positive for Mycoplasma agalactiae DNA and 3.8% (3/78 contained the Mycoplasma mycoides cluster. In the case of ewes, 4.3% (1/23 of the milk samples contained Mycoplasma agalactiae DNA, and 7.5% (3/40 were positive for the Mycoplasma mycoides cluster. Vaginal swabs taken from sheep´s were negative. Analysis of risk factors for mycoplasmosis, showed that goats and sheep flocks on the extensive breeding system are more likely to have mycoplasmosis than those on the intensive breeding system (odds ratio (OR 6.2; p=0.004; meat goat and sheep flocks are more likely to have infection compared to dairy flocks (OR 4.8; p=0.011; unclean animal housing increases the chances of infection (OR 5.0; p=0.031 and not performing quarantine increases the chances of mycoplasmosis (OR 4.6; p=0.042. Based on these findings we conclude that CA syndrome in the semiarid region of Pernambuco state can be associated with Mycoplasma agalactiae and Mycoplasma mycoides cluster.

  12. Egg quality in layers housed in different production systems and submitted to two environmental conditions

    Directory of Open Access Journals (Sweden)

    JAD Barbosa Filho

    2006-03-01

    Full Text Available The production system using cages is a highly polemical issue in Europe, because of the space restriction imposed to laying hens. It is considered that the cage system might compromise important comfort movements, welfare and egg quality. This study evaluated egg quality and welfare of two strains of hens housed in a conventional system (battery laying cages or litter system with nest and perches, and submitted to heat stress or comfort conditions. Two groups of 20 birds (10 Hy-line W36 and 10 Hy-line Brown were submitted to two environmental conditions (26°C and 60% RH or 35°C and 70% RH and two housing systems (cages or litter in the early production phase. Egg quality was analyzed based on egg weight, eggshell thickness, specific gravity, and Haugh units. Yolk and shell contamination by Salmonella sp was also assessed. A significant (p<0.05 reduction in quality parameters was observed in eggs produced by laying hens under heat stress, mainly in the birds housed in cages.

  13. Porous concrete block as an environmental enrichment device increases activity of laying hens in cages.

    Science.gov (United States)

    Holcman, A; Gorjanc, G; Stuhec, I

    2008-09-01

    The purpose of this study was to consider the influence of simple and cheap environmental enrichment such as porous concrete on the behavior of laying hens in conventional cages. Forty brown laying hens were housed in individual wire mesh cages: 20 in experimental cages with porous concrete block provided for pecking and 20 in a control group without concrete block provided. Porous concrete block (5 cm length x 5 cm width x 5 cm height) was mounted on the side wall at the height of the hen's head. Behavior was studied from 42 to 48 wk of age. A group of 8 hens was filmed for 24 h, and the camera was moved each day so that all 40 hens were recorded over 5 d each wk. Videotaping was performed in wk 1, 3, 5, and 7 of the experiment. States (long-term behavior) were observed with 5-min interval recording (feeding, preening, resting, and remaining inactive), whereas events (short-term activities) were observed with instantaneous recording (drinking, pecking concrete, pecking neighbors, pecking cage, and attempting to escape). Data were analyzed with generalized linear mixed model with binomial distribution for states, and Poisson distribution for events. Monte Carlo Markov Chain methods were used to estimate model parameters. Because posterior distributions of quantities of interest were skewed, medians and standard errors are reported. Hens in experimental cages were more active in long-term behavior than controls (64.9 +/- 1.9 and 59.3 +/- 1.9% of the light period, respectively). Correspondingly, hens in the control group showed more long-term inactivity. In addition to pecking the porous concrete block, hens in experimental cages also showed other short-term activities with greater frequency (4.10 +/- 0.31 and 3.51 +/- 0.25 events per h, respectively). Our hypothesis that hens in enriched cages would have a greater level of activity was confirmed. Provision of a piece of porous concrete block as a pecking substrate enriched the environment of the birds at negligible

  14. Temporal and contextual consistency of leadership in homing pigeon flocks.

    Directory of Open Access Journals (Sweden)

    Carlos D Santos

    Full Text Available Organized flight of homing pigeons (Columba livia was previously shown to rely on simple leadership rules between flock mates, yet the stability of this social structuring over time and across different contexts remains unclear. We quantified the repeatability of leadership-based flock structures within a flight and across multiple flights conducted with the same animals. We compared two contexts of flock composition: flocks of birds of the same age and flight experience; and, flocks of birds of different ages and flight experience. All flocks displayed consistent leadership-based structures over time, showing that individuals have stable roles in the navigational decisions of the flock. However, flocks of balanced age and flight experience exhibited reduced leadership stability, indicating that these factors promote flock structuring. Our study empirically demonstrates that leadership and followership are consistent behaviours in homing pigeon flocks, but such consistency is affected by the heterogeneity of individual flight experiences and/or age. Similar evidence from other species suggests leadership as an important mechanism for coordinated motion in small groups of animals with strong social bonds.

  15. Outbreak of infectious laryngotracheitis in large multi-age egg layer chicken flocks in Minas Gerais, Brazil

    Directory of Open Access Journals (Sweden)

    Ingred S. Preis

    2013-05-01

    Full Text Available A recent (November 2010 outbreak of infectious laryngotracheitis (ILT in a multi-age laying hen facility in Minas Gerais state, Brazil, is described. Previous ILT outbreak in laying hens was only notified in São Paulo state, Brazil, in 2002. In the outbreak described here, the affected population was approximately eight million hens, with flock sizes ranging from 100,000 to 2,900,000 chickens. The average mortality ranged from 1 to 6%, and morbidity was around 90% (most of the twenty seven farms of the area were positive for ILT virus. Three multi-age laying farms from one company were selected for this report. Clinical signs included prostration, dyspnea, conjunctivitis, occasional swelling of the paranasal sinuses and bloody mucous nasal discharge. Severely affected chickens presented with dyspnea, gasping and became cyanotic before death. At necropsy, these chickens had fibrinous exudate blocking the larynx and the lumen of cranial part of the trachea. In addition, conjunctivitis with intense hyperemia, edema and sinuses with caseous exudate were present. On histopathology, there were marked necrosis and desquamation of respiratory ephitelium and conjunctiva with numerous syncytial cells formation and fibrinous exudate. Moderate to marked non suppurative (especially lymphocytes and plasma cells infiltration in the lamina propria also was observed. Sixteen out of 20 examined chickens, eosinophilic intranuclear inclusion bodies were observed in the syncytial cells. The DNA extracted from larynx and trachea produced positive PCR results for ILT virus (ILTV DNA using formalin-fixed, paraffin embedded (FFPE samples. Amplicons from a small region of ICP4 gene were submitted to sequencing and showed 100% identity with ILTV EU104910.1 (USA strain, 99% with ILTV JN596963.1 (Australian strain and 91% with ILTV JN580316.1 (Gallid herpesvirus 1 CEO vaccine strain and JN580315.1 (Gallid herpesvirus 1 TCO vaccine strain.

  16. Environmental assessment of three egg production systems--Part I: Monitoring system and indoor air quality.

    Science.gov (United States)

    Zhao, Y; Shepherd, T A; Li, H; Xin, H

    2015-03-01

    To comprehensively assess conventional vs. some alternative laying-hen housing systems under U.S. production conditions, a multi-institute and multi-disciplinary project, known as the Coalition for Sustainable Egg Supply (CSES) study, was carried out at a commercial egg production farm in the Midwestern United States over two single-cycle production flocks. The housing systems studied include a conventional cage house (200,000 hen capacity), an aviary house (50,000 hen capacity), and an enriched colony house (50,000 hen capacity). As an integral part of the CSES project, continual environmental monitoring over a 27-month period described in this paper quantifies indoor gaseous and particulate matter concentrations, thermal environment, and building ventilation rate of each house. Results showed that similar indoor thermal environments in all three houses were maintained through ventilation management and environmental control. Gaseous and particulate matter concentrations of the enriched colony house were comparable with those of the conventional cage house. In comparison, the aviary house had poorer indoor air quality, especially in wintertime, resulting from the presence of floor litter (higher ammonia levels) and hens' activities (higher particulate matter levels) in it. Specifically, daily mean indoor ammonia concentrations had the 95% confidence interval values of 3.8 to 4.2 (overall mean of 4.0) ppm for the conventional cage house; 6.2 to 7.2 (overall mean of 6.7) ppm for the aviary house; and 2.7 to 3.0 (overall mean of 2.8) ppm for the enriched colony house. The 95% confidence interval (overall mean) values of daily mean indoor carbon dioxide concentrations were 1997 to 2170 (2083) ppm for the conventional cage house, 2367 to 2582 (2475) ppm for the aviary house, and 2124 to 2309 (2216) ppm for the enriched colony house. Daily mean indoor methane concentrations were similar for all three houses, with 95% confidence interval values of 11.1 to 11.9 (overall

  17. Mixed species flocking of tits (Parus spp.): a field experiment.

    Science.gov (United States)

    Székely, T; Szép, T; Juhász, T

    1989-03-01

    We tested two general models of flocking behaviour, namely the antipredation model and foraging efficiency model on mixed-species tit flocks (Parus spp.). After food addition the size of mixed-species flocks was significantly less than in the control samples. In the presence of extra food significantly more birds were observed either in monospecific flocks or solitary, than during the control observations. In the presence of a living predator the birds foraged in larger mixed-specifies flocks than during the control observations. In addition, the social behaviour of Great Spotted Woodpecker, Middle Spotted Woodpecker and Nuthatch shifted to mixed-specific flocking. The size of monospecific flocks was independent of both treatments. The density of birds increased significantly after food addition, while in the predator presence the birds tended to leave the forest. These results support the view that both the antipredation model and foraging efficiency model seem to be valid for mixed-species flocking. However, in the case of monospecific flocks, the territory maintenance could be the most important factor.

  18. Some causes of the variable shape of flocks of birds.

    Directory of Open Access Journals (Sweden)

    Charlotte K Hemelrijk

    Full Text Available Flocks of birds are highly variable in shape in all contexts (while travelling, avoiding predation, wheeling above the roost. Particularly amazing in this respect are the aerial displays of huge flocks of starlings (Sturnus vulgaris above the sleeping site at dawn. The causes of this variability are hardly known, however. Here we hypothesise that variability of shape increases when there are larger local differences in movement behaviour in the flock. We investigate this hypothesis with the help of a model of the self-organisation of travelling groups, called StarDisplay, since such a model has also increased our understanding of what causes the oblong shape of schools of fish. The flocking patterns in the model prove to resemble those of real birds, in particular of starlings and rock doves. As to shape, we measure the relative proportions of the flock in several ways, which either depend on the direction of movement or do not. We confirm that flock shape is usually more variable when local differences in movement in the flock are larger. This happens when a flock size is larger, b interacting partners are fewer, c the flock turnings are stronger, and d individuals roll into the turn. In contrast to our expectations, when variability of speed in the flock is higher, flock shape and the positions of members in the flock are more static. We explain this and indicate the adaptive value of low variability of speed and spatial restriction of interaction and develop testable hypotheses.

  19. Effects of Octacosanol Extracted from Rice Bran on the Laying Performance, Egg Quality and Blood Metabolites of Laying Hens.

    Science.gov (United States)

    Peng, Kai; Long, Lei; Wang, Yuxi; Wang, Shunxi

    2016-10-01

    A 42-d study with 384 Hy-line brown laying hens was conducted to assess the effects of dietary octacosanol supplementation on laying performance, egg quality and blood metabolites of laying hens. Hens were randomly allocated into 4 dietary groups of 8 cages each, which were fed basal diet supplemented with 0 (Control), 9 (OCT9), 18 (OCT18), and 27 (OCT27) mg/kg diet of octacosanol isolated from rice bran, respectively. The experiment was conducted in an environmental controlled house and hens were fed twice daily for ad libitum intake. Laying performance was determined over the 42-d period, and egg quality as well as blood metabolites were estimated on d 21 and d 42. Diets in OCT18 and OCT27 increased (pfeed conversion rate and levels of total cholesterol, triglyceride and low density lipoprotein cholesterol in the serum as compared to those of Control. Feed intake, yolk color, yolk diameter, eggshell thickness and high density lipoprotein cholesterol were similar (p>0.05) among treatments. Results demonstrate that supplementing 18 to 27 mg/kg diet of rice bran octacosanol can improve laying rate and egg quality and reduce blood lipid of laying hens.

  20. Modeling the flocking propensity of passerine birds in two Neotropical habitats.

    Science.gov (United States)

    Pomara, Lars Y; Cooper, Robert J; Petit, Lisa J

    2007-08-01

    We examined the importance of mixed-species flock abundance, individual bird home range size, foraging height, and foraging patch characteristics in predicting the propensity for five Neotropical passerine bird species (Slaty Antwren, Myrmotherula schisticolor; Golden-crowned Warbler, Basileuterus culicivorus; Slate-throated Redstart, Myioborus miniatus; Wilson's Warbler, Wilsonia pusilla; and Black-and-white Warbler, Mniotilta varia) to forage within flocks, rather than solitarily. We used study plots in primary mid-elevation forest and in shade coffee fields in western Panama. We expected that all species would spend as much time as possible flocking, but that the social and environmental factors listed above would limit compatibility between flock movements and individual bird movements, explaining variability in flocking propensity both within and among species. Flocking propensity was well predicted by home range size and flock abundance together, for four of the five species. While flock abundance was uniform across plots, home range sizes varied among species and plots, so that home range size appeared to be the principle factor limiting flocking propensity. Estimates of flock abundance were still required, however, for calculating flocking propensity values. Foraging height and patch characteristics slightly improved predictive ability for the remaining species, M. miniatus. In general, individual birds tended to join flocks whenever one was available inside their home range, regardless of a flock's specific location within the home range. Flocking propensities of individual species were lower in shade coffee fields than in forests, and probably vary across landscapes with variations in habitat. This variability affects the stability and species composition of flocks, and may affect survival rates of individual species.

  1. Greater Sage-Grouse (Centrocercus Urophasianus) Hen Survival: Effects of Raptors, Anthropogenic and Landscape Features, and Hen Behavior

    OpenAIRE

    Dinkins, Jonathan B.; Conover, Michael R.; Kirol, Christopher P.; Beck, Jeffrey L.; Frey, S. Nicole

    2014-01-01

    Survival of breeding-age hens has been identified as the demographic rate with the greatest potential to influence population growth of Greater Sage-Grouse (Centrocercus urophasianus (Bonaparte, 1827); hereafter “Sage-Grouse”). During 2008–2011, we collected summer survival data from 427 Sage-Grouse hens in southern Wyoming, USA. We assessed the effects of raptor densities, anthropogenic features, landscape features, and Sage-Grouse hen behavior on Sage-Grouse hen survival. Survival of Sage-G...

  2. Rural poultry production in two agro-ecological zones of Uganda

    International Nuclear Information System (INIS)

    Illango, J.; Etoori, A.; Olupot, H.; Mabonga, J.

    2002-01-01

    A baseline study on rural poultry production, management and health was conducted in six selected villages in an agro-pastoral and montane zone of Uganda during the wet and dry season. In the 114 rural households visited, the farmers were interviewed by using a questionnaire. Poultry flocks were examined and samples were collected for laboratory investigations. A free-range management system with mixed poultry species was practiced by farmers in both zones. The major poultry flock parameters in the agro-pastoral and montane zone were, respectively, mean flock size of 22 (with a range of 3-65) and 17.5 (with a range of 6-60); mean hen:cock ratio of 2.6 to 1 and 4.8 to 1; mean egg production per hen per year of 8.8 and 11.5; mean hatchability of 70.8% and 85.7%; mean chick mortality of 39.6% and 28.6%. The flock ownership was single, mixed or shared among family households. Women were more involved in most of the activities regarding poultry management, although in both zones a division of labour existed within the household. Men predominantly made the decisions on sale, consumption and treatment of poultry. The most important health problems in the flocks in both zones in the two seasons were coughing, diarrhoea, fowl pox and internal parasites. It was concluded that the major constraints affecting rural poultry production in the two zones were diseases especially Newcastle disease and parasites, inadequate housing and poor feed supplementation especially in the dry season. Women had important responsibilities in rural poultry production in the two zones. The findings form the basis for an assessment of the effects of interventions on rural poultry production in the two zones. (author)

  3. The development of egg-laying behaviour and nest-site selection in a strain of white laying hens

    NARCIS (Netherlands)

    Rietveld - Piepers, B.

    1987-01-01

    Since World War II livestock husbandry has been highly intensificated. This trend was most obvious in the poultry industry. Laying hens used to be housed outdoors in free-range systems, but nowadays these systems have almost entirely been replaced by the battery-cage. In the early sixties

  4. Preliminary Evaluation of a Nest Usage Sensor to Detect Double Nest Occupations of Laying Hens

    Directory of Open Access Journals (Sweden)

    Mauro Zaninelli

    2015-01-01

    Full Text Available Conventional cage systems will be replaced by housing systems that allow hens to move freely. These systems may improve hens’ welfare, but they lead to some disadvantages: disease, bone fractures, cannibalism, piling and lower egg production. New selection criteria for existing commercial strains should be identified considering individual data about laying performance and the behavior of hens. Many recording systems have been developed to collect these data. However, the management of double nest occupations remains critical for the correct egg-to-hen assignment. To limit such events, most systems adopt specific trap devices and additional mechanical components. Others, instead, only prevent these occurrences by narrowing the nest, without any detection and management. The aim of this study was to develop and test a nest usage “sensor”, based on imaging analysis, that is able to automatically detect a double nest occupation. Results showed that the developed sensor correctly identified the double nest occupation occurrences. Therefore, the imaging analysis resulted in being a useful solution that could simplify the nest construction for this type of recording system, allowing the collection of more precise and accurate data, since double nest occupations would be managed and the normal laying behavior of hens would not be discouraged by the presence of the trap devices.

  5. Rubin H. Flocks and Colloidal Gold Treatments for Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Henry M. Rosevear

    2011-01-01

    Full Text Available In the early 1950s, Rubin H. Flocks of the University of Iowa began to treat prostate cancer patients with colloidal gold (Au198 therapy, evolving his technique over nearly 25 years in 1515 patients. We reviewed the long-term outcomes of Flocks' prostate cancer patients as compared to those patients treated by other methods at the University of Iowa before Flocks' chairmanship. We reviewed archived patient records, Flocks' published data, and long-term survival data from the Iowa Tumor Registry to determine short- and long-term outcomes of Flocks' work with colloidal gold. We also reviewed the literature of Flocks' time to compare his outcomes against those of his contemporaries. The use of colloidal gold, either as primary or adjunctive therapy, provided short- and long-term survival benefit for the majority of Flocks' patients as compared to historical treatment options (p < 0.001. Flocks' use of colloidal gold for the treatment of locally advanced prostate cancer offered short- and long-term survival benefits compared to other contemporary treatments.

  6. INFLUENCE OF PLANT ESSENTIAL OILS ON SELECTED PARAMETERS OF THE PERFORMANCE OF LAYING HENS

    Directory of Open Access Journals (Sweden)

    Henrieta ARPÁŠOVÁ

    2010-10-01

    Full Text Available The experiment was designed to investigate the effects of feed supplementation with essential oils on egg weight and body mass of laying hens. Hens of the laying breed Isa Brown were randomly divided at the day of hatching into 3 groups (n=26 and fed for 45 weeks on diets which differed in kind of essential oil supplemented. Hens were fed from day 1 by the standard feed mixture. Laying hens accepted fodder ad libitum. In the control group hens took feed mixture without additions, in the first experimental group the feed mixture was supplemented with 0.25 ml/kg thyme essential oil and in the second one hens got hyssop essential oil in the same dose of 0.25 ml/kg. The housing system satisfied enriched cage requirements specified by the Directive 1999/74 EC. The useful area provided for one laying hen presented 943.2 cm2. The equipment of cage consisted of roosts, place for rooting in ashes – synthetic grass, nest and equipment for shortening of clutches. The results showed that the average body weight for a rearing period was in order groups: 736.15±523.49; 747.20±541.6 and 721.95±522.57 (g±SD. Differences between groups were not significant (P>0.05. The average body weight during the laying period was 1763.85±171.46; 1786.08±192.09 and 1729.73±129.12 g for control, thyme oil and hyssop oil supplementation respectively. During the laying period there were significant differences in body weight between control and experimental group with hyssop essential oil supplementation (P<0.05 and between both experimental groups (P<0.01. No significant differences were found out between control group and experimental groups (P>0.05 in egg weight (58.36±4.91; 58.82±4.95 and 58.26±5.33 g respectively.

  7. Aceitação sensorial de reestruturados empanados elaborados com filé de peito de galinhas matrizes de corte e poedeiras comerciais Sensory acceptance of nuggets prepared with broiler breeder and spent layer hens breast meat

    Directory of Open Access Journals (Sweden)

    Tatiana Pacheco Nunes

    2006-12-01

    Full Text Available Em 2005, no Brasil, o alojamento de galinhas poedeiras comerciais e de matrizes de corte somados foi de 109 milhões de cabeças, sendo que um número próximo a este deve ter sido descartado no mesmo período. Este grande número de galinhas descartadas contrasta com a falta de mercado consumidor e o baixo valor comercial alcançado por estas aves. A utilização da carne de galinhas na elaboração de produtos de conveniência poderia agregar valor e ampliar o consumo desta matéria-prima. Diante do exposto, o objetivo deste trabalho foi elaborar produtos empanados tipo nuggets, utilizando carne de galinhas de descarte (matrizes de corte e poedeiras comercias brancas e avaliar a aceitação pelo consumidor destes produtos, em comparação com nuggets elaborados com carne de frango. Os produtos desenvolvidos foram avaliados por análise sensorial, utilizando testes de aceitação e de intenção de compra em localização central (400 provadores. Não foram encontradas diferenças (p > 0,05 na aceitação sensorial nem na intenção de compra entre os três diferentes produtos avaliados. Concluiu-se que a elaboração de produtos empanados pode representar uma boa alternativa para a utilização de filés de peito de galinhas, agregando maior valor a estas aves ao final do ciclo de postura.In Brazil, the flock size of layer and broiler breeder hens housed in 2005 was 109 million. A similar number of hens might be spent in this period. This great number of spent hens contrasts with the absence of consumer market and the low commercial value reached by these birds. The manufacture of convenience products using spent hens meat could add value and elevate the consumption of this raw material. Thus, the purpose of this study was to develop nuggets made with spent hens (white layers and broiler breeders meat and evaluate the consumer acceptance of these products in comparison to nuggets elaborated with broiler meat. Sensory evaluation of acceptance

  8. Flock worker's lung: chronic interstitial lung disease in the nylon flocking industry.

    Science.gov (United States)

    Kern, D G; Crausman, R S; Durand, K T; Nayer, A; Kuhn, C

    1998-08-15

    Two young men working at a nylon flocking plant in Rhode Island developed interstitial lung disease of unknown cause. Similar clusters at the same company's Canadian plant were reported previously. To define the extent, clinicopathologic features, and potential causes of the apparent disease outbreak. Case-finding survey and retrospective cohort study. Academic occupational medicine program. All workers employed at the Rhode Island plant on or after 15 June 1990. Symptomatic employees had chest radiography, pulmonary function tests, high-resolution computed tomography, and serologic testing. Those with unexplained radiographic or pulmonary function abnormalities underwent bronchoalveolar lavage, lung biopsy, or both. The case definition of "flock worker's lung" required histologic evidence of interstitial lung disease (or lavage evidence of lung inflammation) not explained by another condition. Eight cases of flock worker's lung were identified at the Rhode Island plant. Three cases were characterized by a high proportion of eosinophils (25% to 40%) in lavage fluid. Six of the seven patients who had biopsy had histologic findings of nonspecific interstitial pneumonia, and the seventh had bronchiolitis obliterans organizing pneumonia. All seven of these patients had peribronchovascular interstitial lymphoid nodules, usually with germinal centers, and most had lymphocytic bronchiolitis and interstitial fibrosis. All improved after leaving work. Review of the Canadian tissue specimens showed many similar histologic findings. Among the 165-member study cohort, a 48-fold or greater increase was seen in the sex-adjusted incidence rate of all interstitial lung disease. Work in the nylon flocking industry poses substantial risk for a previously unrecognized occupational interstitial lung disease. Nylon fiber is the suspected cause of this condition.

  9. Impulsive Flocking of Dynamical Multiagent Systems with External Disturbances

    Directory of Open Access Journals (Sweden)

    Fujun Han

    2017-01-01

    Full Text Available Flocking motion of multiagent systems is influenced by various external disturbances in complex environment. By applying disturbance observer, flocking of multiagent systems with exogenous disturbances is studied. Based on the robust features of impulsive control, a distributed impulsive control protocol is presented with disturbance observer, and flocking motion of multiagent systems is analyzed. Moreover, a sufficient condition is obtained to ensure the flocking motion of multiagent systems following a leader. Finally, simulation results show the validity of the theoretical conclusion.

  10. Development of furnished cages for laying hens.

    Science.gov (United States)

    Appleby, M C; Walker, A W; Nicol, C J; Lindberg, A C; Freire, R; Hughes, B O; Elson, H A

    2002-09-01

    1. A 3-year trial was carried out of cages for laying hens, occupying a full laying house. The main cage designs used were 5000 cm2 in area, 50 cm high at the rear and furnished with nests and perches. F cages had a front rollaway nest at the side, lined with artificial turf. FD cages also had a dust bath containing sand over the nest. H cages had two nest hollows at the side, one in front of the other. They were compared with conventional cages 2500 cm2 in area and 38 cm high at the rear. 2. Cages were stocked with from 4 to 8 ISA Brown hens per cage, resulting in varied allowances of area, feeder and perch per bird. No birds were beak trimmed. In F and FD cages two further treatments were applied: nests and dust baths were sometimes fitted with gates to exclude birds from dust baths in the morning and from both at night; elevated food troughs, with a lip 33 cm above the cage floor, were compared with standard troughs. 3. Management of the house was generally highly successful, with temperature control achieved by ventilation. Egg production was above breeders' standards and not significantly affected by cage design. More eggs per bird were collected when there were fewer birds per cage but food consumption also then tended to be higher. 4. The number of downgraded eggs was variable, with some tendency for more in furnished cages. Eggs laid in dust baths were often downgraded. Those laid at the back of the cage were frequently dirty because of accumulation of droppings. H nests were unsuccessful, with less than 50% of eggs laid in the nest hollows. However, up to 93% of eggs were laid in front rollaways, and few of these were downgraded. 5. Feather and foot damage were generally less in furnished than in conventional cages, greater where there were more birds per cage. With an elevated food trough there was less feather damage but more overgrowth of claws. In year 2, mortality was greater in cages with more birds. 6. Pre-laying behaviour was mostly settled in

  11. Environmental study of nylon flocking process.

    Science.gov (United States)

    Burkhart, J; Piacitelli, C; Schwegler-Berry, D; Jones, W

    1999-05-14

    Environmental measurements for a variety of gas, particulate, and microbiological agents have been made in order to characterize exposures associated with the nylon flocking process. Of all agents measured, particulate is the predominant exposure. Levels of total particulate ranged from O.1 to 240 mg/m3 (x = 11.4 mg/m3). Average respirable particulate was 2.2 mg/m3, ranging from 0.5 to 39.9 mg/m3. Highest levels of particulates were found in the flocking room, and direct reading dust measurements indicate that the highest peak exposures are associated with "blowdown" (a cleaning procedure used between flocking runs). The nature of the airborne particles was investigated using polarized light and scanning electron microscopy. Air samples were found to contain flock particles (fibers nominally 10-15 microm in diameter by about 1000 microm in length) and a variety of respirable particles types, several of which were linked directly to the process. Of special interest were elongated respirable particles, which by microscopic analysis, complemented with melting-point determination, were found to be shreds of nylon.

  12. Economic Impacts of White Chick Syndrome in Ontario, Canada.

    Science.gov (United States)

    Long, Kathleen E; Hastie, Gordon M; Ojkić, Davor; Brash, Marina L

    2017-09-01

    A cluster of 12 cases of White Chick Syndrome (WCS) in broiler breeder flocks producing affected progeny occurred from June to November 2015 in two broiler chicken hatcheries owned by a single company in Ontario, Canada. Cases were identified by the presence of typical chicks in the hatchery characterized by pale to white down, enlarged abdomens, and occasionally brown wiry fluff on the dorsum of the neck that were generally weak. Affected broiler breeder flocks experienced egg production drops of 0% to 15% and hatchability drops of 1.8% to 49.1%. Some flocks experienced increased feed clean-up duration and/or reduced hatching egg weight. The financial impacts of WCS to affected hatching egg producers averaged $5,912 CAD (US$4,417) per 10 000 hens and were as great as $16,788 CAD (US$12,544) per 10 000 hens. The financial impacts of WCS to the affected hatcheries averaged $1,723 CAD (US$1,287) per 10 000 broiler breeder hens and were as great as $4,096 (US$3,060) per 10 000 hens.

  13. Effect of aluminum sulfate on litter composition and ammonia emission in a single flock of broilers up to 42 days of age.

    Science.gov (United States)

    Madrid, J; López, M J; Orengo, J; Martínez, S; Valverde, M; Megías, M D; Hernández, F

    2012-08-01

    New alternatives are necessary if the environmental impact linked to intensive poultry production is to be reduced, and different litter handling methods should be explored. Among these, acidifying amendments added to poultry litters has been suggested as a management practice to help reduce the potential environmental effect involved in multiple flock cycles. There have been several studies on the use of aluminum sulfate (alum) and its benefits, but almost no data are available under farm conditions in Europe. An experiment with Ross 308 broilers from 1 to 42 days of age was conducted to evaluate the effect of alum on litter composition, the solubility of some mineral elements and NH3 emission during a single flock-rearing period in commercial houses located in southeast Spain. Broilers were placed on clean wood shavings in four commercial houses, containing 20 000 broilers each. Before filling, alum was applied at a rate of 0.25 kg/m2 to the wood shavings of two poultry houses, whereas the remaining two were used as control. Litter from each poultry house was sampled every 3 to 5 days. Ammonia emissions from the poultry houses were monitored from 37 to 42 days of age. In comparison with the control group, alum treatment significantly reduced the pH level of the litter (P litter showed, on average, a higher electrical conductivity than the control litter (5.52 v. 3.63 dS/m). The dry matter (DM) and total N and P contents did not show differences between the treatments (P > 0.05). Regarding the NH4 +-N content, alum-treated litter showed a higher value than the untreated litter, with an average difference of 0.16 ± 0.07% (on a DM basis). On average, alum-treated litter had lower water-soluble P, Zn and Cu contents than the untreated litter. Alum noticeably reduced the in-house ammonia concentration (P litter, with a corresponding positive effect on the building environment and poultry health. For these reasons, litter amendment with alum could be recommended as a

  14. Spontaneous flocking in human groups.

    Science.gov (United States)

    Belz, Michael; Pyritz, Lennart W; Boos, Margarete

    2013-01-01

    Flocking behaviour, as a type of self-organised collective behaviour, is described as the spatial formation of groups without global control and explicit inter-individual recruitment signals. It can be observed in many animals, such as bird flocks, shoals or herds of ungulates. Spatial attraction between humans as the central component of flocking behaviour has been simulated in a number of seminal models but it has not been detected experimentally in human groups so far. The two other sub-processes of this self-organised collective movement - collision avoidance and alignment - are excluded or held constant respectively in this study. We created a computer-based, multi-agent game where human players, represented as black dots, moved on a virtual playground. The participants were deprived of social cues about each other and could neither communicate verbally nor nonverbally. They played two games: (1) Single Game, where other players were invisible, and (2) Joint Game, where each player could see players' positions in a local radius around himself/herself. We found that individuals approached their neighbours spontaneously if their positions were visible, leading to less spatial dispersion of the whole group compared to moving alone. We conclude that human groups show the basic component of flocking behaviour without being explicitly instructed or rewarded to do so. Copyright © 2012 Elsevier B.V. All rights reserved.

  15. Boundary information inflow enhances correlation in flocking.

    Science.gov (United States)

    Cavagna, Andrea; Giardina, Irene; Ginelli, Francesco

    2013-04-19

    The most conspicuous trait of collective animal behavior is the emergence of highly ordered structures. Less obvious to the eye, but perhaps more profound a signature of self-organization, is the presence of long-range spatial correlations. Experimental data on starling flocks in 3D show that the exponent ruling the decay of the velocity correlation function, C(r)~1/r(γ), is extremely small, γflocks. The effect of the dynamical field is to create an information inflow from border to bulk that triggers long-range spin-wave modes, thus giving rise to an anomalously long-ranged correlation. The biological origin of this phenomenon can be either exogenous-information produced by environmental perturbations is transferred from boundary to bulk of the flock-or endogenous-the flock keeps itself in a constant state of dynamical excitation that is beneficial to correlation and collective response.

  16. Effects of catecholamines on ovary morphology, blood concentrations of estradiol-17beta, progesterone, zinc, triglycerides and rate of ovulation in domestic hens.

    Science.gov (United States)

    Ebeid, T A; Eid, Y Z; El-Abd, E A; El-Habbak, M M

    2008-04-15

    The present study is an attempt to shed more light on the role of epinephrine (EP) and norepinephrine (NE) in regulating ovarian follicular development, folliculogenesis and ovulation in laying hens. Sixty Egyptian local cross females (Mandarah), 50 weeks old, were individually housed and equally divided into three treatments: control (saline, 0.9% NaCl), EP (0.15 mg epinephrine/hen/day) and NE (0.75 mg norepinephrine/hen/day) (n=20). Animals were injected intramuscularly once a day for 15 successive days. At the end of the experimental period, 10 females from each treatment were randomly chosen, weighed and killed by decapitation. Ovaries and oviducts and ovarian follicles were examined. Plasma concentrations of estradiol-17beta, progesterone, zinc and triglyceride were determined. Results indicated that the ovaries of NE- and EP-treated hens were more developed than those of control hens being heavier and containing more yellow yolk-filled follicles. EP or NE significantly increased the ovulation rate and plasma concentrations of estradiol-17beta, progesterone, zinc and triglyceride compared with control treatment. It could be concluded that catecholamines may have a part in promoting ovarian follicular development and in stimulating ovulation in laying hens at the end of their reproductive lives.

  17. Risk factors and likelihood of Campylobacter colonization in broiler flocks

    Directory of Open Access Journals (Sweden)

    SL Kuana

    2007-09-01

    Full Text Available Campylobacter was investigated in cecal droppings, feces, and cloacal swabs of 22 flocks of 3 to 5 week-old broilers. Risk factors and the likelihood of the presence of this agent in these flocks were determined. Management practices, such as cleaning and disinfection, feeding, drinkers, and litter treatments, were assessed. Results were evaluated using Odds Ratio (OR test, and their significance was tested by Fisher's test (p<0.05. A Campylobacter prevalence of 81.8% was found in the broiler flocks (18/22, and within positive flocks, it varied between 85 and 100%. Campylobacter incidence among sample types was homogenous, being 81.8% in cecal droppings, 80.9% in feces, and 80.4% in cloacal swabs (230. Flocks fed by automatic feeding systems presented higher incidence of Campylobacter as compared to those fed by tube feeders. Litter was reused in 63.6% of the farm, and, despite the lack of statistical significance, there was higher likelihood of Campylobacter incidence when litter was reused. Foot bath was not used in 45.5% of the flocks, whereas the use of foot bath associated to deficient lime management increased the number of positive flocks, although with no statiscal significance. The evaluated parameters were not significantly associated with Campylobacter colonization in the assessed broiler flocks.

  18. Hepatic lipidosis in turkeys.

    Science.gov (United States)

    Gazdzinski, P; Squires, E J; Julian, R J

    1994-01-01

    Two flocks of 14,000 twenty-week-old turkey hens each experienced increased mortality due to hepatic lipidosis. Some hens showed signs of dyspnea and cyanosis before death. Necropsy revealed dark muscles and enlarged livers with pale areas and numerous hemorrhages. Petechial and ecchymotic hemorrhages were also found on the abdominal fat and epicardium. Lung congestion and edema were prominent. In the heart and blood vessels, the blood was uncoagulated. Mortality was elevated for 12 days and resulted in the death of 0.7% of the turkey hens in one flock and 1.7% in the other. Vitamin E administered in water at a dose of 25 IU per hen appeared to reduce mortality. The nutritional and environmental factors that may contribute to the development of hepatic lipidosis in turkeys are discussed.

  19. Sustainability of egg production in the United States--the policy and market context.

    Science.gov (United States)

    Mench, J A; Sumner, D A; Rosen-Molina, J T

    2011-01-01

    The US egg industry is being pressured from many directions to change its production practices, particularly to address concerns about hen welfare in conventional cage systems. Responding to similar pressures, in 1999, the European Union banned conventional laying cages starting in 2012. This now impending European ban has led to the development of several alternative housing systems. These include noncage systems like aviaries and modified (enriched or furnished) cages that include perches, areas in which the hens can forage and dustbathe, and nests. Understanding the European experience is valuable as the United States considers the future direction of the egg industry. In the United States, the proportion of eggs produced in alternative systems is small (less than 5% of output) but growing, in part due to market and political incentives for systems that provide hens with more behavioral freedom than conventional cages. Animal welfare, however, is only one element of a sustainable production system. Other elements include those related to public values, the environment, economics, worker health, and food safety and quality. Eggs are a primary source of animal protein globally, and the United States is the third largest producer of eggs in the world, behind China and the European Union. The national table egg flock comprises about 280 million hens housed in all regions but with approximately 60% of eggs produced in the 10 leading states. Adopting new housing systems will have substantial effects on costs and other aspects of egg production on both a regional and national scale, with some positive effects but also potential negative effects that need to be carefully considered. This paper discusses the US egg industry in the context of legislation and standards related to hen housing systems. It also addresses initiatives by retailers, nongovernmental organizations, and private certification organizations to shape production practices in the egg industry as well as

  20. Flocking and invariance of velocity angles.

    Science.gov (United States)

    Liu, Le; Huang, Lihong; Wu, Jianhong

    2016-04-01

    Motsch and Tadmor considered an extended Cucker-Smale model to investigate the flocking behavior of self-organized systems of interacting species. In this extended model, a cone of the vision was introduced so that outside the cone the influence of one agent on the other is lost and hence the corresponding influence function takes the value zero. This creates a problem to apply the Motsch-Tadmor and Cucker-Smale method to prove the flocking property of the system. Here, we examine the variation of the velocity angles between two arbitrary agents, and obtain a monotonicity property for the maximum cone of velocity angles. This monotonicity permits us to utilize existing arguments to show the flocking property of the system under consideration, when the initial velocity angles satisfy some minor technical constraints.

  1. Qualidade do ovo de galinhas poedeiras criadas em galpões no semi-árido paraibano Quality of eggs of laying hens reared in poultry houses in the semi-arid Paraiba

    Directory of Open Access Journals (Sweden)

    Jair L. Trindade

    2007-12-01

    Full Text Available Avaliar índices ambientais dos galpões e os zootécnicos em aves de postura leve da linhagem Lohamann, em condições de verão e inverno de 2005 na região do semi-árida paraibana, foi o objetivo primordial deste trabalho, no qual se utilizaram 34.500 aves com diferentes idades: 32, 50, 60 e 71 semanas, acondicionadas em quatro galpões. Avaliaram-se os índices ambientais temperatura do ar, umidade relativa do ar, índice de temperatura do globo negro e umidade, carga térmica de radiação e velocidade do vento; e os produtivos (produção total de ovos, peso do ovo, peso do albúmen, peso da gema e peso das cascas, parâmetros geométricos (área e volume e a unidade Haugh (UH do ovo, em função da idade. Quanto ao ambiente no interior dos aviários, não houve diferença significativa na media dos índices ambientais, que ficaram dentro da zona de conforto. A idade das aves teve influência nos índices produção total, peso do ovo e peso da gema. A maior produção foi obtida com aves mais jovens, enquanto o peso do ovo e da gema foi com aves de maior idade. Os parâmetros geométricos volume e área do ovo não foram influenciados pela idade das aves. Conforme a UH os ovos de melhor qualidade se referem aos das aves com 32 e 50 semanas.The objective of this research was to evaluate production indexes for laying hens of the Lohamann lineage, under the summer and winter conditions of 2005, in São José da Mata district of Campina Grande, which is located in the Paraíban semi-arid region. 34.500 hens were used with ages of 32, 50, 60 and 71 weeks, and which were reared in four poultry houses. The production indexes (total production of eggs, egg weight, albumen weight, egg yolk weight, and rinds weight, geometric parameters (area and volume and Haugh unit of egg were calculated as a function of hen age. The production indexes in all rearing systems followed the technical recommendations. The age of the hens influenced the indexes of

  2. The effect of different feed restriction programs on reproductive performance, efficiency, frame size, and uniformity in broiler breeder hens.

    Science.gov (United States)

    de Beer, M; Coon, C N

    2007-09-01

    Two experiments were conducted to determine the effect of feed restriction programs on breeder reproductive performance. In experiment 1, every day (ED), skip-a-day (SK), 4-3, and 5-2 programs were compared. Diets did not differ, and feed intake was identical in all groups. Four hundred twenty pullets were reared on each program. At 21 wk, 80 breeders from each program were individually housed to record performance parameters. Body weight and frame size were larger in ED pullets than SK, 4-3, or 5-2 despite equal intakes. Hens fed ED reached sexual maturity at a younger age than other groups. Hens fed ED also produced more total and settable eggs than SK hens. Egg weight was heavier in 5-2 hens than in ED with 4-3 and SK intermediate. Efficiency of feed utilization was best in ED hens. In experiment 2 the same programs were tested, but pullets were reared to reach equal BW. One hundred seventy-five pullets were reared on each program, of which 60 were housed. Feed intake was greater for SK, 4-3, and 5-2 than ED pullets to reach the same BW. Frame size did not differ, indicating that BW was the cause of differences in experiment 1. In experiment 2, differences in performance were attenuated but not eliminated by feeding to reach equal BW, suggesting that metabolic factors aside from BW are altered by feeding programs. The 5-2 produced larger eggs than ED with the trend among programs being identical to that in experiment 1. These results suggest that metabolic changes such as increased lipogenesis or alterations in body composition may result in larger eggs in feeding programs that include off-feed days. Mortality, fertility, and hatchability were not affected by feeding programs in either experiment. Body composition analysis indicated the importance of total lean protein mass as a threshold for the onset of sexual maturity. Programs like SK are less efficient than ED and may result in reduced performance.

  3. Diffusion of individual birds in starling flocks

    Science.gov (United States)

    Cavagna, A.; Queirós, S. M. Duarte; Giardina, I.; Stefanini, F.; Viale, M.

    2013-01-01

    Flocking is a paradigmatic example of collective animal behaviour, where global order emerges out of self-organization. Each individual has a tendency to align its flight direction with those of neighbours, and such a simple form of interaction produces a state of collective motion of the group. When compared with other cases of collective ordering, a crucial feature of animal groups is that the interaction network is not fixed in time, as each individual moves and continuously changes its neighbours. The possibility to exchange neighbours strongly enhances the stability of global ordering and the way information is propagated through the group. Here, we assess the relevance of this mechanism in large flocks of starlings (Sturnus vulgaris). We find that birds move faster than Brownian walkers both with respect to the centre of mass of the flock, and with respect to each other. Moreover, this behaviour is strongly anisotropic with respect to the direction of motion of the flock. We also measure the amount of neighbours reshuffling and find that neighbours change in time exclusively as a consequence of the random fluctuations in the individual motion, so that no specific mechanism to keep one's neighbours seems to be enforced. On the contrary, our findings suggest that a more complex dynamical process occurs at the border of the flock. PMID:23407827

  4. Genetic diversity of Gallibacterium anatis isolates from different chicken flocks

    DEFF Research Database (Denmark)

    Bojesen, A.M.; Torpdahl, Mia; Christensen, H.

    2003-01-01

    of chickens from an organic, egg-producing flock and a layer parent flock. A subset of strains was also characterized by pulsed-field gel electrophoresis and biotyping. The organic flock isolates were characterized by more than 94% genetic similarity, indicating that only a single clone was apparent...

  5. Duration of the vector period of house flies for Campylobacter jejuni estimated by experimental infection series

    DEFF Research Database (Denmark)

    Skovgård, Henrik; Hald, Birthe

    The house fly Musca domestica may act as a vector and transmit Campylobacter to broiler flocks. We determined the duration of the vector period for C. jejuni at various temperatures and inoculation doses. For the temperature experiment, laboratory reared house flies (n = 375) were inoculated with...

  6. A model for an economically optimal replacement of a breeder flock.

    Science.gov (United States)

    Yassin, Hurria; Velthuis, Annet G J; Giesen, Gerard W J; Oude Lansink, Alfons G J M

    2012-12-01

    A deterministic model is developed to support the tactical and operational replacement decisions at broiler breeder farms. The marginal net revenue approach is applied to determine the optimal replacement age of a flock. The objective function of the model maximizes the annual gross margin over the flock's production cycle. To calculate the gross margin, future egg production, fertility, or hatchability of the eggs, revenues and variable costs of a flock were estimated. For tactical decisions, the optimal laying length is the age at which the average gross margin of an average flock is maximal. For operational decisions, a flock should be replaced when the marginal gross margin of a replaceable flock is less than the average gross margin of an average flock. To demonstrate the model, a broiler breeder flock from a Dutch breeder farm was used. A sensitivity analysis showed that the optimal replacement decision, for both tactical and operational management, is sensitive to the decrease in the weekly egg production after the peak and the prices of feed and hatching eggs. The effect of the decrease in weekly fertility after the peak on the replacement decision is related to the payment system for hatching eggs.

  7. Composition and foraging behaviour of mixed-species flocks in two ...

    African Journals Online (AJOL)

    Enlarged flock size resulted from a general increase in flocking tendency of all species. At the species level, the Long-billed Crombec Sylvietta rufescens and the Chinspot Batis Batis molitor showed clear feeding benefits within flocks, whereas tits obtained no feeding benefit. Crombecs and batises also changed foraging ...

  8. Infectious Bronchitis Vaccination Protocols for Laying Hens

    Directory of Open Access Journals (Sweden)

    A. Sulaiman

    2011-12-01

    Full Text Available A research was conducted to investigate the effects of vaccination protocols for Infectious Bronchitis (IB on egg production, egg quality, and IB antibody titres of laying hens. Different initial vaccination (Control, VicS eye, VicS spray, VicS water, A3 eye, A3 spray, and A3 water for IB were administered to day-old Isa Brown hens. Half the hens were revaccinated regularly during lay whereas the other hens were not vaccinated. Results showed that initial vaccination treatment had significant effects on hen day egg production and egg quality of egg weight, shell reflectivity, shell breaking strength, shell thickness, albumen height, Haugh Units, and IB antibody titre levels, but had no effect on percentage of shell and yolk colour. Egg weight and shell reflectivity were less favourable in the control hens. In contrast, shell breaking strength and shell thickness were highest for the group that initially received A3 vaccine in water. However, regular revaccination had some deleterious effects on egg production and egg quality. There were no significant effects of revaccination on IB antibody titres. It is concluded that there was little advantage in regularly revaccinating laying hens for IB virus, since they had received appropriate initial vaccination.

  9. Response of male turkeys hatched from first-cycle and force-molted breeder hens to a regimen providing progressive feeds by weight and the value of increased lysine prior to marketing.

    Science.gov (United States)

    Moran, E T; Krueger, K K; Acar, N

    1992-11-01

    Male poults originating from 41- and 85-wk-old Nicholas Large White breeder turkey hens were compared using a six-feed system provided on the basis of weight. Each source of poult was compared further in its response to lysine at .65 and .80% in the final feed (14.5% CP and 3.40 kcal AMEn/g) before marketing at 18 wk of age. Poults from 85-wk-old hens were heavier at placement than those from 41-wk-old hens. Equalization of body weights occurred once the allotment of starting feed had been consumed and for the most part remained similar thereafter. Increasing lysine content of the final feed did not improve body weight of both sources of birds at marketing (P < .13). Feed conversions included accrued mortality, and treatment differences were not apparent. Commercial processing of the flock and measurements on sample birds indicated no ready differences in chilled carcass yield nor proportions of parts occurred among treatments. The overall effects of breeder age with the progeny were negligible, and the .65% level of lysine that presently serves as the 1984 National Research Council minimum requirement when associated with 14% CP and 3.30 kcal/g appears to be adequate for the Nicholas strain of turkey from 16 to 18 wk of age.

  10. Local equilibrium in bird flocks

    Science.gov (United States)

    Mora, Thierry; Walczak, Aleksandra M.; Del Castello, Lorenzo; Ginelli, Francesco; Melillo, Stefania; Parisi, Leonardo; Viale, Massimiliano; Cavagna, Andrea; Giardina, Irene

    2016-12-01

    The correlated motion of flocks is an example of global order emerging from local interactions. An essential difference with respect to analogous ferromagnetic systems is that flocks are active: animals move relative to each other, dynamically rearranging their interaction network. This non-equilibrium characteristic has been studied theoretically, but its impact on actual animal groups remains to be fully explored experimentally. Here, we introduce a novel dynamical inference technique, based on the principle of maximum entropy, which accommodates network rearrangements and overcomes the problem of slow experimental sampling rates. We use this method to infer the strength and range of alignment forces from data of starling flocks. We find that local bird alignment occurs on a much faster timescale than neighbour rearrangement. Accordingly, equilibrium inference, which assumes a fixed interaction network, gives results consistent with dynamical inference. We conclude that bird orientations are in a state of local quasi-equilibrium over the interaction length scale, providing firm ground for the applicability of statistical physics in certain active systems.

  11. Prevalence and antimicrobial susceptibility of thermophilic Campylobacter in organic and conventional broiler flocks

    DEFF Research Database (Denmark)

    Heuer, Ole Eske; Pedersen, Karl; Andersen, J.S.

    2001-01-01

    Aims: To determine the flock prevalence and to estimate the within flock prevalence of Campylobacter in broiler flocks from different rearing systems, and to determine the antimicrobial susceptibility of Campylobacter isolates to selected antimicrobial substances. Methods and Results: One hundred...... and sixty broiler flocks originating from organic, conventional and extensive indoor production farms were investigated for the presence of Campylobacter at the time of slaughter. Campylobacter isolates from a subsample of positive flocks were subjected to susceptibility testing. Campylobacter spp. were...... isolated from 100% of organic broiler flocks, from 36.7% of conventional broiler flocks and from 49.2% of extensive indoor broiler flocks. Six of 62 Campylobacter isolates were resistant to one or more of the antimicrobials tested. Conclusions: These results indicate that the special characteristics...

  12. Broiler-Housing Conditions Affect the Performance

    Directory of Open Access Journals (Sweden)

    D Mesa

    Full Text Available ABSTRACT In the last decades animal production has considerably increased worldwide to sustain an ever-growing human population. Among animal reared for consumption purposes, chickens are undoubtedly one of the most successful, mainly due to their rapid growth rate. The development of broiler farming has been accompanied in recent years by a substantial attention to animal welfare. This study is aimed at assessing the effects of different housing conditions on both feed conversion ratio and mortality of male broiler flocks through a large-scale study (more than 100 million birds involving 977 farms belonging to one major producer. For this, we evaluated nine features of the housing system using a linear model with random effect. The features were: roofing, floor, drinkers, feeders, water source, color curtain color, management, light and ventilation. A total of 3516 poultry flocks were assessed. Positive ventilation, metal and clay roof, dirt floor and owner management were shown to reduced mortality. Concrete floor, negative ventilation, blue curtains, fluorescent lightening, owner management, tap water and well water significantly improved FCR. We discuss our findings in relation with economic constraints and provide advices to encourage farmers using simple devices that will improve both production and chicken survival.

  13. Design of nest access grids and perches in front of the nests: Influence on the behavior of laying hens.

    Science.gov (United States)

    Stämpfli, K; Buchwalder, T; Fröhlich, E K F; Roth, B A

    2013-04-01

    In aviary systems for laying hens, it is important to provide suitable nest access platforms in front of the nests, allowing hens to reach and explore each of the nests easily. This access platform is needed to achieve good nest acceptance by the hens and thereby prevent mislaid eggs. In the present experiment, the behavior of hens using 2 different nest access platforms, a plastic grid and 2 wooden perches, was examined. Furthermore, the nests were placed on both sides of the aviary rack (corridor side and outdoor side), either integrated into the aviary rack itself (integrated nest; IN) or placed on the walls of the pens (wall nest; WN), resulting in a 2 × 2 factorial design Four thousand five hundred white laying hens were housed in 20 test pens. The eggs in the nests and mislaid eggs were collected daily, and the behavior of hens on the nest accesses was filmed during wk 25 and 26, using focal observation and scan sampling methods. More balancing, body contact, and agonistic interactions were expected for nests with perches, whereas more walking and nest inspections were expected for nests with grids. There were more mislaid eggs and balancing found in pens equipped with nests with wooden perches. More agonistic interactions and balancing, less standing, and a longer duration of nest inspection were found with the WN compared with the IN. Interactions between platform design and position of the nests were found for duration of nest visits, body contact, and walking, with the highest amount for WN equipped with plastic grids. Nests on the corridor side were favored by the hens. Nest-related behaviors, such as nest inspection, standing, and walking, decreased over time as did the number of hens on the nest accesses, whereas sitting increased. These results indicate that the hens had more difficulties in gripping the perches as designed. The lower number of hens on the nest access platforms in front of IN may be due to a better distribution around nests and tier

  14. Environmental assessment of three egg production systems–Part I: Monitoring system and indoor air quality

    Science.gov (United States)

    Zhao, Y.; Shepherd, T. A.; Li, H.; Xin, H.

    2015-01-01

    To comprehensively assess conventional vs. some alternative laying-hen housing systems under U.S. production conditions, a multi-institute and multi-disciplinary project, known as the Coalition for Sustainable Egg Supply (CSES) study, was carried out at a commercial egg production farm in the Midwestern United States over two single-cycle production flocks. The housing systems studied include a conventional cage house (200,000 hen capacity), an aviary house (50,000 hen capacity), and an enriched colony house (50,000 hen capacity). As an integral part of the CSES project, continual environmental monitoring over a 27-month period described in this paper quantifies indoor gaseous and particulate matter concentrations, thermal environment, and building ventilation rate of each house. Results showed that similar indoor thermal environments in all three houses were maintained through ventilation management and environmental control. Gaseous and particulate matter concentrations of the enriched colony house were comparable with those of the conventional cage house. In comparison, the aviary house had poorer indoor air quality, especially in wintertime, resulting from the presence of floor litter (higher ammonia levels) and hens’ activities (higher particulate matter levels) in it. Specifically, daily mean indoor ammonia concentrations had the 95% confidence interval values of 3.8 to 4.2 (overall mean of 4.0) ppm for the conventional cage house; 6.2 to 7.2 (overall mean of 6.7) ppm for the aviary house; and 2.7 to 3.0 (overall mean of 2.8) ppm for the enriched colony house. The 95% confidence interval (overall mean) values of daily mean indoor carbon dioxide concentrations were 1997 to 2170 (2083) ppm for the conventional cage house, 2367 to 2582 (2475) ppm for the aviary house, and 2124 to 2309 (2216) ppm for the enriched colony house. Daily mean indoor methane concentrations were similar for all three houses, with 95% confidence interval values of 11.1 to 11.9 (overall

  15. Switching hierarchical leadership mechanism in homing flight of pigeon flocks

    Science.gov (United States)

    Chen, Duxin; Vicsek, Tamás; Liu, Xiaolu; Zhou, Tao; Zhang, Hai-Tao

    2016-06-01

    To explore the fascinating inter-individual interaction mechanism governing the abundant biological grouping behaviors, more and more efforts have been devoted to collective motion investigation in recent years. Therein, bird flocking is one of the most intensively studied behaviors. A previous study (Nagy M. et al., Nature, 464 (2010) 890.) claims the existence of a well-defined hierarchical structure in pigeon flocks, which implies that a multi-layer leadership network leads to the occurrence of highly coordinated pigeon flock movements. However, in this study, by using high-resolution GPS data of homing flight of pigeon flocks, we reveal an explicit switching hierarchical mechanism underlying the group motions of pigeons. That is, a pigeon flock has a long-term leader for smooth moving trajectories, whereas the leading tenure passes to a temporary one upon sudden turns or zigzags. Therefore, the present observation helps explore more deeply into the principle of a huge volume of bird flocking dynamics. Meanwhile, from the engineering point of view, it may shed some light onto industrial multi-robot coordination and unmanned air vehicle formation control.

  16. Outdoor flocking of quadcopter drones with decentralized model predictive control.

    Science.gov (United States)

    Yuan, Quan; Zhan, Jingyuan; Li, Xiang

    2017-11-01

    In this paper, we present a multi-drone system featured with a decentralized model predictive control (DMPC) flocking algorithm. The drones gather localized information from neighbors and update their velocities using the DMPC flocking algorithm. In the multi-drone system, data packages are transmitted through XBee ® wireless modules in broadcast mode, yielding such an anonymous and decentralized system where all the calculations and controls are completed on an onboard minicomputer of each drone. Each drone is a double-layered agent system with the coordination layer running multi-drone flocking algorithms and the flight control layer navigating the drone, and the final formation of the flock relies on both the communication range and the desired inter-drone distance. We give both numerical simulations and field tests with a flock of five drones, showing that the DMPC flocking algorithm performs well on the presented multi-drone system in both the convergence rate and the ability of tracking a desired path. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  17. Starling flock networks manage uncertainty in consensus at low cost.

    Directory of Open Access Journals (Sweden)

    George F Young

    Full Text Available Flocks of starlings exhibit a remarkable ability to maintain cohesion as a group in highly uncertain environments and with limited, noisy information. Recent work demonstrated that individual starlings within large flocks respond to a fixed number of nearest neighbors, but until now it was not understood why this number is seven. We analyze robustness to uncertainty of consensus in empirical data from multiple starling flocks and show that the flock interaction networks with six or seven neighbors optimize the trade-off between group cohesion and individual effort. We can distinguish these numbers of neighbors from fewer or greater numbers using our systems-theoretic approach to measuring robustness of interaction networks as a function of the network structure, i.e., who is sensing whom. The metric quantifies the disagreement within the network due to disturbances and noise during consensus behavior and can be evaluated over a parameterized family of hypothesized sensing strategies (here the parameter is number of neighbors. We use this approach to further show that for the range of flocks studied the optimal number of neighbors does not depend on the number of birds within a flock; rather, it depends on the shape, notably the thickness, of the flock. The results suggest that robustness to uncertainty may have been a factor in the evolution of flocking for starlings. More generally, our results elucidate the role of the interaction network on uncertainty management in collective behavior, and motivate the application of our approach to other biological networks.

  18. Starling Flock Networks Manage Uncertainty in Consensus at Low Cost

    Science.gov (United States)

    Young, George F.; Scardovi, Luca; Cavagna, Andrea; Giardina, Irene; Leonard, Naomi E.

    2013-01-01

    Flocks of starlings exhibit a remarkable ability to maintain cohesion as a group in highly uncertain environments and with limited, noisy information. Recent work demonstrated that individual starlings within large flocks respond to a fixed number of nearest neighbors, but until now it was not understood why this number is seven. We analyze robustness to uncertainty of consensus in empirical data from multiple starling flocks and show that the flock interaction networks with six or seven neighbors optimize the trade-off between group cohesion and individual effort. We can distinguish these numbers of neighbors from fewer or greater numbers using our systems-theoretic approach to measuring robustness of interaction networks as a function of the network structure, i.e., who is sensing whom. The metric quantifies the disagreement within the network due to disturbances and noise during consensus behavior and can be evaluated over a parameterized family of hypothesized sensing strategies (here the parameter is number of neighbors). We use this approach to further show that for the range of flocks studied the optimal number of neighbors does not depend on the number of birds within a flock; rather, it depends on the shape, notably the thickness, of the flock. The results suggest that robustness to uncertainty may have been a factor in the evolution of flocking for starlings. More generally, our results elucidate the role of the interaction network on uncertainty management in collective behavior, and motivate the application of our approach to other biological networks. PMID:23382667

  19. Bacterial contamination of table eggs and the influence of housing systems

    NARCIS (Netherlands)

    Reu, de K.; Messens, W.; Heyndrickx, M.; Rodenburg, T.B.; Uyttendaele, M.; Herman, L.

    2008-01-01

    With the introduction of alternative housing systems for laying hens in the EU, recent research has focussed on the bacterial contamination of table eggs, e.g. eggshell and egg content contamination. Contamination of eggshells with aerobic bacteria is generally higher for nest eggs from non-cage

  20. Monochromatic light-emitting diode (LED source in layers hens during the second production cycle

    Directory of Open Access Journals (Sweden)

    Rodrigo Borille

    2015-09-01

    Full Text Available ABSTRACTLight is an important environmental factor for birds, allowing not only their vision, but also influencing their physiological responses, such as behavioral and reproductive activity. The objective of this experiment was to evaluate the impact of different colors of monochromatic light (LED sources in laying hens production during the second laying cycle. The study was conducted in an experimental laying house during 70 days. A total of 300 laying hens Isa Brown® genetic strain, aged 95 weeks, in the second laying cycle were used in the study. The artificial light sources used were blue, yellow, green, red and white. The light regimen was continuous illumination of 17 h per day (12 h natural and 5 h artificial in a daily light regimen of 17L:5D (light: dark. The Latin Square design was adopted with five treatments (five colors divided into five periods, and five boxes, with six replicates of ten birds in each box. The production and egg quality were evaluated. The different colors of light source did not affect production parameters or egg quality (p > 0.05. The monochromatic light source may be considered as an alternative to artificial lighting in laying hens during the second production cycle.

  1. The Influence of Keel Bone Damage on Welfare of Laying Hens

    Directory of Open Access Journals (Sweden)

    Anja B. Riber

    2018-02-01

    Full Text Available This article reviews current knowledge about welfare implications of keel bone damage in laying hens. As an initial part, we shortly describe the different conditions and present major risk factors as well as findings on the prevalence of the conditions. Keel bone damage is found in all types of commercial production, however with varying prevalence across systems, countries, and age of the hens. In general, the understanding of animal welfare is influenced by value-based ideas about what is important or desirable for animals to have a good life. This review covers different types of welfare indicators, including measures of affective states, basic health, and functioning as well as natural living of the birds, thereby including the typical public welfare concerns. Laying hens with keel bone fractures show marked behavioral differences in highly motivated behavior, such as perching, nest use, and locomotion, indicating reduced mobility and potentially negative affective states. It remains unclear whether keel bone fractures affect hen mortality, but there seem to be relations between the fractures and other clinical indicators of reduced welfare. Evidence of several types showing pain involvement in fractured keel bones has been published, strongly suggesting that fractures are a source of pain, at least for weeks after the occurrence. In addition, negative effects of fractures have been found in egg production. Irrespective of the underlying welfare concern, available scientific evidence showed that keel bone fractures reduce the welfare of layers in modern production systems. Due to the limited research into the welfare implications of keel bone deviation, evidence of the consequences of this condition is not as comprehensive and clear. However, indications have been found that keel bone deviations have a negative impact on the welfare of laying hens. In order to reduce the occurrence of the conditions as well as to examine how the affected

  2. Pop hole passages and welfare in furnished cages for laying hens.

    Science.gov (United States)

    Wall, H; Tauson, R; Elwinger, K

    2004-02-01

    1. This study included two designs of furnished cages for 16 hens; H-cages divided into two apartments by a partition with pop holes in the middle of the cage, and fully open O-cages, without a partition. The hypothesis was that in this rather large group of birds the pop hole partition would benefit the birds by allowing them to avoid or escape from potential cannibals, feather-peckers or aggressive hens. All cages had two nests, two perches and one litter box. 2. A total of 10 cages (5 H and 5 O) were stocked with Lohmann Selected Leghorn (LSL) and 8 cages (4 H and 4 O) with Hy-Line W36. No birds were beak-trimmed. 3. Heterophil/lymphocyte (H/L) ratios, duration of tonic immobility (TI) and exterior appearance (scoring of plumage condition and wounds at comb or around cloaca) were used as indicators of well-being. Total mortality and deaths due to cannibalism were also recorded. 4. Visits to nests and passages through partition pop holes were studied in samples of 35 and 21 birds, respectively, using a technique based on passive integrated transponder (PIT) tags. 5. Cage design (H- vs O-cage) had no effect on the welfare traits chosen. 6. Hy-Line birds showed higher H/L ratios, longer duration of TI and better plumage condition than LSL birds. These differences are discussed in terms of stress thresholds and copying strategies. 7. On days when a hen made visits to nests, the visiting frequency was 1.4 and the total time in the nest was 41 min on average. Hens made use of the pop hole passages between 1 and 8 times per hen and day. 8. Overall low levels of aggression, lack of injuries or deaths due to cannibalism, and plumage condition indicating moderate feather pecking, together imply a low need to escape. The pop holes were used frequently and birds distributed well between compartments showing that the system worked well. However, at this group size there was no evidence in the measured traits that H-cages provided a better housing environment.

  3. Flock sizes and sex ratios of canvasbacks in Chesapeake Bay and North Carolina

    Science.gov (United States)

    Haramis, G.M.; Derleth, E.L.; Link, W.A.

    1994-01-01

    Knowledge of the distribution, size, and sex ratios of flocks of wintering canvasbacks (Aythya valisineria) is fundamental to understanding the species' winter ecology and providing guidelines for management. Consequently, in winter 1986-87, we conducted 4 monthly aerial photographic surveys to investigate temporal changes in distribution, size, and sex ratios of canvasback flocks in traditional wintering areas of Chesapeake Bay and coastal North Carolina. Surveys yielded 35mm imagery of 194,664 canvasbacks in 842 flocks. Models revealed monthly patterns of flock size in North Carolina and Virginia, but no pattern of change in Maryland. A stepwise analysis of flock size and sex ratio fit a common positive slope (increasing proportion male) for all state-month datasets, except for North Carolina in February where the slope was larger (P lt 0.001). State and month effects on intercepts were significant (P lt 0.001) and confirmed a previously identified latitudinal gradient in sex ratio in the survey region. There was no relationship between flock purity (% canvasbacks vs. other species) and flock size except in North Carolina in January, February, and March when flock purity was related to flock size. Contrasting characteristics in North Carolina with regard to flock size (larger flocks) and flock purity suggested that proximate factors were reinforcing flocking behavior and possibly species fidelity there. Of possible factors, the need to locate foraging sites within this large, open-water environment was hypothesized to be of primary importance. Comparison of January 1981 and 1987 sex ratios indicated no change in Maryland, but lower (P lt 0.05) canvasback sex ratios (proportion male) in Virginia and North Carolina.

  4. Flocking of quad-rotor UAVs with fuzzy control.

    Science.gov (United States)

    Mao, Xiang; Zhang, Hongbin; Wang, Yanhui

    2018-03-01

    This paper investigates the flocking problem of quad-rotor UAVs. Considering the actual situations, we derived a new simplified quad-rotor UAV model which is more reasonable. Based on the model, the T-S fuzzy model of attitude dynamic equation and the corresponding T-S fuzzy feedback controller are discussed. By introducing a double-loop control construction, we adjust its attitude to realize the position control. Then a flocking algorithm is proposed to achieve the flocking of the quad-rotor UAVs. Compared with the flocking algorithm of the mass point model, we dealt with the collision problem of the quad-rotor UAVs. In order to improve the airspace utilization, a more compact configuration called quasi e-lattice is constructed to guarantee the compact flight of the quad-rotor UAVs. Finally, numerical simulations are provided to illustrate the effectiveness of the obtained theoretical results. Copyright © 2018 ISA. Published by Elsevier Ltd. All rights reserved.

  5. AD HOC TEAMWORK BEHAVIORS FOR INFLUENCING A FLOCK

    Directory of Open Access Journals (Sweden)

    Katie Genter

    2016-02-01

    Full Text Available Ad hoc teamwork refers to the challenge of designing agents that can influence the behavior of a team, without prior coordination with its teammates. This paper considers influencing a flock of simple robotic agents to adopt a desired behavior within the context of ad hoc teamwork. Specifically, we examine how the ad hoc agents should behave in order to orient a flock towards a target heading as quickly as possible when given knowledge of, but no direct control over, the behavior of the flock. We introduce three algorithms which the ad hoc agents can use to influence the flock, and we examine the relative importance of coordinating the ad hoc agents versus planning farther ahead when given fixed computational resources. We present detailed experimental results for each of these algorithms, concluding that in this setting, inter-agent coordination and deeper lookahead planning are no more beneficial than short-term lookahead planning.

  6. Flocking and rendezvous in distributed robotics

    CERN Document Server

    Francis, Bruce A

    2016-01-01

    This brief describes the coordinated control of groups of robots using only sensory input – and no direct external commands. Furthermore, each robot employs the same local strategy, i.e., there are no leaders, and the text also deals with decentralized control, allowing for cases in which no single robot can sense all the others. One can get intuition for the problem from the natural world, for example, flocking birds. How do they achieve and maintain their flying formation? Recognizing their importance as the most basic coordination tasks for mobile robot networks, the brief details flocking and rendezvous. They are shown to be physical illustrations of emergent behaviors with global consensus arising from local interactions. The authors extend the consideration of these fundamental ideas to describe their operation in flying robots and prompt readers to pursue further research in the field.  Flocking and Rendezvous in Distributed Robotics will provide graduate students a firm grounding in the subject, w...

  7. Pigeon interaction mode switch-based UAV distributed flocking control under obstacle environments.

    Science.gov (United States)

    Qiu, Huaxin; Duan, Haibin

    2017-11-01

    Unmanned aerial vehicle (UAV) flocking control is a serious and challenging problem due to local interactions and changing environments. In this paper, a pigeon flocking model and a pigeon coordinated obstacle-avoiding model are proposed based on a behavior that pigeon flocks will switch between hierarchical and egalitarian interaction mode at different flight phases. Owning to the similarity between bird flocks and UAV swarms in essence, a distributed flocking control algorithm based on the proposed pigeon flocking and coordinated obstacle-avoiding models is designed to coordinate a heterogeneous UAV swarm to fly though obstacle environments with few informed individuals. The comparative simulation results are elaborated to show the feasibility, validity and superiority of our proposed algorithm. Copyright © 2017 ISA. Published by Elsevier Ltd. All rights reserved.

  8. The ability of White Leghorn hens with trimmed comb and wattles to thermoregulate.

    Science.gov (United States)

    Al-Ramamneh, D S; Makagon, M M; Hester, P Y

    2016-08-01

    It is estimated that each year over 19 million pullets in the United States have their combs partially trimmed at a young age to improve egg production and feed efficiency. A possible disadvantage of trimming is that the comb and wattles may be essential for thermoregulation during hot weather allowing for conductive cooling of the blood through vasodilation of superficial vessels in these integumentary tissues. The objective of this study was to investigate the effects of partial comb and wattle removal, performed at 21 d of age, on the ability of White Leghorns to thermoregulate before, during, and after an imposed heating episode that averaged 34.6°C for 50.5 h. An increase in mortality at 20 h and body temperature at 48 h post initiation of the heating episode demonstrated that hens with trimmed comb and wattles were not able to cope with heat stress as effectively as controls. The increase in wattle temperature in controls as compared to trimmed hens during the heating episode and following heat stress provides supportive evidence that blood pools to the peripheral surface for conductive heat loss. During high temperatures typical of summer, trimmed hens attempted to compensate for their lack of ability to transfer heat from their comb and wattles to the environment through increased proportion of panting and wing spreading. Under less extreme conditions with lowered ambient temperatures, the trimming of the comb and wattles did not impair the ability of hens to thermoregulate, as body temperatures and behavior were similar to controls with no mortality. Egg weight was the only production parameter adversely affected by the trimming of the comb and wattles as compared to controls. The implication is that hens need their combs and wattles to thermoregulate effectively during periods of high environmental temperature. Pullets should not be subjected to a comb and wattle trim if they are housed in laying facilities that are not appropriately cooled during the

  9. Prevalence of Campylobacter jejuni in poultry breeder flocks

    Directory of Open Access Journals (Sweden)

    Ludovico Dipineto

    2010-01-01

    Full Text Available The aim of this work is to present the preliminary results of a study about the prevalence of Campylobacter jejuni in poultry breeder flocks. It was examined three different breeder flocks of Bojano in Molise region. A total of 360 cloacal swabs and 80 enviromental swabs was collected. Of the 3 flocks studied, 6.9% tested were positive for Campylobacter spp. The most-prevalent isolated species is C. jejuni (8.2%. Only 3 of the 360 cloacal swabs samples examined were associated with C. coli. The environmental swabs resulted negative. This results confirms again that poultry is a reservoir of this germ.

  10. Acute coenurosis of dairy sheep from 11 flocks in Greece.

    Science.gov (United States)

    Giadinis, N D; Psychas, V; Polizopoulou, Z; Papadopoulos, E; Papaioannou, N; Komnenou, A Th; Thomas, A-L; Petridou, E J; Kritsepi-Konstantinou, M; Lafi, S Q; Brellou, G D

    2012-07-01

    A syndrome of acute neurological dysfunction with increased mortality was observed in lambs of 10 dairy sheep flocks and adult animals in one flock in Central and Northern Greece. Each farmer completed a questionnaire regarding the management and feeding of their flocks. In seven of the 11 flocks the affected animals were grazing pasture, while in the remaining four flocks (5, 8, 9, 10) the animals were fed alfalfa hay (Medicago sativa) and concentrates indoors. A follow-up study of the affected flocks was conducted during the next 12 months. Of 42 sheep with acute coenurosis that were examined, the most prominent neurological abnormalities were ataxia, depression, blindness, scoliosis, coma and dysmetria. Except for the four sheep that were comatose, all other animals had normal body temperatures and their appetites remained normal or were slightly decreased. Haematological findings of 15 examined sheep were within normal limits. The affected sheep were subject to euthanasia. A histopathological examination was performed in 13 cases. Faecal samples from dogs associated with these flocks were negative for taeniid infections. During the following 12 months cases of chronic coenurosis in these flocks were observed. In the 42 animals that were necropsied, the main gross findings were cystic formations between 0.5-1 cm in diameter with translucent walls that were seen lying free on the leptomeninges or partly penetrating the brain tissue, sterile microabscecess and brain necrosis. Histopathological evaluation of tissue sections of 13 brains showed multifocal purulent or pyogranulomatous meningoencephalitis, accompanied by eosinophilic infiltrations. No bacteria were isolated following bacterial culture of brain tissue Parasitological examination of the cysts from five cases revealed whitish specks on the transparent cyst wall and germination membrane representing the scolices. Acute coenurosis was diagnosed in all cases studied. Acute coenurosis can be one of the

  11. Effect of Red Pepper (Capsicum frutescens) Powder or Red Pepper Pigment on the Performance and Egg Yolk Color of Laying Hens.

    Science.gov (United States)

    Li, Huaqiang; Jin, Liji; Wu, Feifei; Thacker, Philip; Li, Xiaoyu; You, Jiansong; Wang, Xiaoyan; Liu, Sizhao; Li, Shuying; Xu, Yongping

    2012-11-01

    Two experiments were conducted to study the effects of red pepper (Capsicum frutescens) powder or red pepper pigment on the performance and egg yolk color of laying hens. In Exp. 1, 210, thirty-wk old, Hy-line Brown laying hens were fed one of seven diets containing 0.3, 0.6, 1.2, 2.0, 4.8 or 9.6 ppm red pepper pigment or 0.3 ppm carophyll red. Each diet was fed to three replicate batteries of hens with each battery consisting of a row of five cages of hens with two hens per cage (n = 3). In Exp. 2, 180, thirty-wk old, Hyline Brown laying hens, housed similarly to those in Exp. 1, were fed an unsupplemented basal diet as well as treatments in which the basal diet was supplemented with 0.8% red pepper powder processed in a laboratory blender to an average particle size of 300 μm, 0.8% red pepper powder processed as a super fine powder with a vibrational mill (44 μm) and finally 0.8% red pepper powder processed as a super fine powder with a vibrational mill but mixed with 5% Na2CO3 either before or after grinding. A diet supplemented with 0.3 ppm carophyll red pigment was also included (n = 3). In both experiments, hens were fed the red pepper powder or pigment for 14 days. After feeding of the powder or pigment was terminated, all hens were fed the basal diet for eight more days to determine if the dietary treatments had any residual effects. In Exp. 1, there were no differences in egg-laying performance, feed consumption or feed conversion ratio due to inclusion of red pepper pigment in the diet. Average egg weight was higher (pfeeding red pepper powder did not affect egg-laying performance, feed consumption or feed conversion ratio (p>0.05). However, compared with the control group, supplementation with all of the red pepper powder treatments increased egg weight (pfeed additives for improving egg yolk color for laying hens.

  12. Emergence of the scale-invariant proportion in a flock from the metric-topological interaction.

    Science.gov (United States)

    Niizato, Takayuki; Murakami, Hisashi; Gunji, Yukio-Pegio

    2014-05-01

    Recently, it has become possible to more precisely analyze flocking behavior. Such research has prompted a reconsideration of the notion of neighborhoods in the theoretical model. Flocking based on topological distance is one such result. In a topological flocking model, a bird does not interact with its neighbors on the basis of a fixed-size neighborhood (i.e., on the basis of metric distance), but instead interacts with its nearest seven neighbors. Cavagna et al., moreover, found a new phenomenon in flocks that can be explained by neither metric distance nor topological distance: they found that correlated domains in a flock were larger than the metric and topological distance and that these domains were proportional to the total flock size. However, the role of scale-free correlation is still unclear. In a previous study, we constructed a metric-topological interaction model on three-dimensional spaces and showed that this model exhibited scale-free correlation. In this study, we found that scale-free correlation in a two-dimensional flock was more robust than in a three-dimensional flock for the threshold parameter. Furthermore, we also found a qualitative difference in behavior from using the fluctuation coherence, which we observed on three-dimensional flocking behavior. Our study suggests that two-dimensional flocks try to maintain a balance between the flock size and flock mobility by breaking into several smaller flocks. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  13. Serotype and genotype diversity and hatchery transmission of Campylobacter jejuni in commercial poultry flocks

    DEFF Research Database (Denmark)

    Petersen, L.; Nielsen, E.M.; On, Stephen L.W.

    2001-01-01

    , 314 C jejuni and 32 C coli isolates from parent and broiler flocks and from the surroundings of broiler houses were typed by flagellin gene PCR/RFLP fla-typing), and selected isolates were also typed by serotyping and macrorestriction profiling using PFGE (MRP/PFGE). The combined typing results showed...... discriminated by fla-typing as well as by MRP/PFGE, except for a few cases where individual isolates belonging to two different clones were found to have altered fla-types. Similarly, one C coli clone showed pronounced fla-type variation. The present results lead to the conclusion that vertical transmission...

  14. Effect of Red Pepper ( Powder or Red Pepper Pigment on the Performance and Egg Yolk Color of Laying Hens

    Directory of Open Access Journals (Sweden)

    Huaqiang Li

    2012-11-01

    Full Text Available Two experiments were conducted to study the effects of red pepper (Capsicum frutescens powder or red pepper pigment on the performance and egg yolk color of laying hens. In Exp. 1, 210, thirty-wk old, Hy-line Brown laying hens were fed one of seven diets containing 0.3, 0.6, 1.2, 2.0, 4.8 or 9.6 ppm red pepper pigment or 0.3 ppm carophyll red. Each diet was fed to three replicate batteries of hens with each battery consisting of a row of five cages of hens with two hens per cage (n = 3. In Exp. 2, 180, thirty-wk old, Hyline Brown laying hens, housed similarly to those in Exp. 1, were fed an unsupplemented basal diet as well as treatments in which the basal diet was supplemented with 0.8% red pepper powder processed in a laboratory blender to an average particle size of 300 μm, 0.8% red pepper powder processed as a super fine powder with a vibrational mill (44 μm and finally 0.8% red pepper powder processed as a super fine powder with a vibrational mill but mixed with 5% Na2CO3 either before or after grinding. A diet supplemented with 0.3 ppm carophyll red pigment was also included (n = 3. In both experiments, hens were fed the red pepper powder or pigment for 14 days. After feeding of the powder or pigment was terminated, all hens were fed the basal diet for eight more days to determine if the dietary treatments had any residual effects. In Exp. 1, there were no differences in egg-laying performance, feed consumption or feed conversion ratio due to inclusion of red pepper pigment in the diet. Average egg weight was higher (p0.05. However, compared with the control group, supplementation with all of the red pepper powder treatments increased egg weight (p<0.05. All the red pepper powder treatments also increased (p<0.05 the yolk color score compared with the control. The results of the present study suggest that both red pepper powder and pigment are effective feed additives for improving egg yolk color for laying hens.

  15. Oral food desensitization in children with IgE-mediated hen's egg allergy: a new protocol with raw hen's egg.

    Science.gov (United States)

    Meglio, Paolo; Giampietro, Paolo G; Carello, Rossella; Gabriele, Ida; Avitabile, Simona; Galli, Elena

    2013-02-01

    Hen's egg allergy affects young children and can cause severe allergic reactions. Avoidance results in dietary limitations and can affect the quality of life, especially in cases where potentially life-threatening reactions exist. Our objective was to desensitize children with moderate-severe IgE-mediated hen's egg allergy over a 6-month period, by introducing increasing and very gradual daily doses of raw hen's egg in order to enable the children to assume 25ml of this food, or to induce tolerance to the highest possible dose. The protocol foresaw the egg reintroduction in the home setting. In this randomized, controlled open study, 20 hen's egg allergic children (10 in the active group) were admitted. A convincing history or a positive double-blind placebo-controlled food challenge confirmed the diagnosis. Oral desensitization was performed with increasing doses starting from 0.27 mg of hen's egg proteins (1 drop of raw hen's egg diluted 1:100). We adopted an original, mathematically calculated protocol in order to ensure a constant, daily increment of doses. 8/10 children (80%) in the active group achieved the daily intake of 25ml over a 6-month period. One child (10%) could tolerate up to 2ml/day while another child (10%) failed the desensitization. Six months after enrolment only 2 children in the control group (20%) could tolerate hen's egg. We successfully desensitized 8/10 children with IgE-mediated hen's egg allergy in a 6-month period. The partial outcome in the child who could tolerate 2ml/day reduced the risk of severe reactions after unnoticed introduction of egg. A regular protocol that ensures a daily constant increase of doses helps to reduce possible adverse events, thus improving safety and effectiveness. © 2012 John Wiley & Sons A/S.

  16. Clusterflock: a flocking algorithm for isolating congruent phylogenomic datasets.

    Science.gov (United States)

    Narechania, Apurva; Baker, Richard; DeSalle, Rob; Mathema, Barun; Kolokotronis, Sergios-Orestis; Kreiswirth, Barry; Planet, Paul J

    2016-10-24

    Collective animal behavior, such as the flocking of birds or the shoaling of fish, has inspired a class of algorithms designed to optimize distance-based clusters in various applications, including document analysis and DNA microarrays. In a flocking model, individual agents respond only to their immediate environment and move according to a few simple rules. After several iterations the agents self-organize, and clusters emerge without the need for partitional seeds. In addition to its unsupervised nature, flocking offers several computational advantages, including the potential to reduce the number of required comparisons. In the tool presented here, Clusterflock, we have implemented a flocking algorithm designed to locate groups (flocks) of orthologous gene families (OGFs) that share an evolutionary history. Pairwise distances that measure phylogenetic incongruence between OGFs guide flock formation. We tested this approach on several simulated datasets by varying the number of underlying topologies, the proportion of missing data, and evolutionary rates, and show that in datasets containing high levels of missing data and rate heterogeneity, Clusterflock outperforms other well-established clustering techniques. We also verified its utility on a known, large-scale recombination event in Staphylococcus aureus. By isolating sets of OGFs with divergent phylogenetic signals, we were able to pinpoint the recombined region without forcing a pre-determined number of groupings or defining a pre-determined incongruence threshold. Clusterflock is an open-source tool that can be used to discover horizontally transferred genes, recombined areas of chromosomes, and the phylogenetic 'core' of a genome. Although we used it here in an evolutionary context, it is generalizable to any clustering problem. Users can write extensions to calculate any distance metric on the unit interval, and can use these distances to 'flock' any type of data.

  17. Flocking dynamics and roosting behaviour of Meyer's parrot ...

    African Journals Online (AJOL)

    For most of the year, Meyer's parrots in the Okavango Delta do not form large feeding flocks, and groups larger than two or three are probably the result of opportunistic aggregation at favoured food items after dispersion from communal roosts. Communal roosting likely does not facilitate flocking unless the food resources ...

  18. Semi-flocking algorithm for motion control of mobile sensors in large-scale surveillance systems.

    Science.gov (United States)

    Semnani, Samaneh Hosseini; Basir, Otman A

    2015-01-01

    The ability of sensors to self-organize is an important asset in surveillance sensor networks. Self-organize implies self-control at the sensor level and coordination at the network level. Biologically inspired approaches have recently gained significant attention as a tool to address the issue of sensor control and coordination in sensor networks. These approaches are exemplified by the two well-known algorithms, namely, the Flocking algorithm and the Anti-Flocking algorithm. Generally speaking, although these two biologically inspired algorithms have demonstrated promising performance, they expose deficiencies when it comes to their ability to maintain simultaneous robust dynamic area coverage and target coverage. These two coverage performance objectives are inherently conflicting. This paper presents Semi-Flocking, a biologically inspired algorithm that benefits from key characteristics of both the Flocking and Anti-Flocking algorithms. The Semi-Flocking algorithm approaches the problem by assigning a small flock of sensors to each target, while at the same time leaving some sensors free to explore the environment. This allows the algorithm to strike balance between robust area coverage and target coverage. Such balance is facilitated via flock-sensor coordination. The performance of the proposed Semi-Flocking algorithm is examined and compared with other two flocking-based algorithms once using randomly moving targets and once using a standard walking pedestrian dataset. The results of both experiments show that the Semi-Flocking algorithm outperforms both the Flocking algorithm and the Anti-Flocking algorithm with respect to the area of coverage and the target coverage objectives. Furthermore, the results show that the proposed algorithm demonstrates shorter target detection time and fewer undetected targets than the other two flocking-based algorithms.

  19. Flocking ferromagnetic colloids.

    Science.gov (United States)

    Kaiser, Andreas; Snezhko, Alexey; Aranson, Igor S

    2017-02-01

    Assemblages of microscopic colloidal particles exhibit fascinating collective motion when energized by electric or magnetic fields. The behaviors range from coherent vortical motion to phase separation and dynamic self-assembly. Although colloidal systems are relatively simple, understanding their collective response, especially under out-of-equilibrium conditions, remains elusive. We report on the emergence of flocking and global rotation in the system of rolling ferromagnetic microparticles energized by a vertical alternating magnetic field. By combing experiments and discrete particle simulations, we have identified primary physical mechanisms, leading to the emergence of large-scale collective motion: spontaneous symmetry breaking of the clockwise/counterclockwise particle rotation, collisional alignment of particle velocities, and random particle reorientations due to shape imperfections. We have also shown that hydrodynamic interactions between the particles do not have a qualitative effect on the collective dynamics. Our findings shed light on the onset of spatial and temporal coherence in a large class of active systems, both synthetic (colloids, swarms of robots, and biopolymers) and living (suspensions of bacteria, cell colonies, and bird flocks).

  20. Welfare of organic laying hens kept at different indoor stocking densities in a multi-tier aviary system. I: egg laying, and use of veranda and outdoor area

    DEFF Research Database (Denmark)

    Steenfeldt, Sanna; Nielsen, Birte L.

    2015-01-01

    Multi-tier aviary systems are becoming more common in organic egg production. The area on the tiers can be included in the net area available to the hens (also referred to as usable area) when calculating maximum indoor stocking densities in organic systems within the EU. In this article, results...... on egg production, laying behaviour and use of veranda and outdoor area are reported for organic laying hens housed in a multi-tier system with permanent access to a veranda and kept at stocking densities (D) of 6, 9 and 12 hens/m2 available floor area, with concomitant increases in the number of hens...... per trough, drinker, perch and nest space. In a fourth treatment, access to the top tier was blocked reducing vertical, trough and perch access at the lowest stocking density (treatment D6x). In all other aspects than stocking density, the experiment followed the EU regulations on the keeping...

  1. Buckwheat bran (Fagopyrum esculentum as partial replacement of corn and soybean meal in the laying hen diet

    Directory of Open Access Journals (Sweden)

    Domenico Gatta

    2012-01-01

    Full Text Available The effect of partial substitution of corn (-20% and soybean meal (-10% with buckwheat bran (+30% (Fagopyrum esculentum Moench in the diet of ISA-Brown hens was investigated in sixteen 74-week old hens, housed in couple wire cages and submitted to a 16 h light:8 h dark photoperiod. The following traits were measured: body weight, egg production, egg mass, egg quality, feed intake, feed conversion, comparative palatability of ingredients and digestibility of diet. χ2 and non-parametric tests were used for production rate and yolk color score, respectively. ANOVA was used for all other parameters. Comparative choice of buckwheat, corn and soy was checked under different forms in 3 free choice tests. Results show that egg production rate (43.3% vs 50.5%; P<0.05 and feed intake (78.3±0.68 eggs/hen d vs 87.8±0.68 eggs/hen d; P<0.05 increased with the partial introduction of buckwheat bran in the diet. There was no difference in feed conversion between treatments. Nutrient balance confirmed that AMEn of diet was deeply lowered by the buckwheat bran use (6.5 MJ/kg vs 10.1 MJ/kg , due to the high fibre content of buckwheat bran (263 g/kg. Maize was always the most preferred ingredient, buckwheat bran was consumed more than expected in absence of any preference, and soybean was the food least chosen. Buckwheat bran can be used as an ingredient feed for low-producing laying hens; it induces a feed-intake increase, partially balanced by improved egg-production rates and a tendency to better albumen Haugh units.

  2. Effects of phyto-oestrogen quercetin on productive performance, hormones, reproductive organs and apoptotic genes in laying hens.

    Science.gov (United States)

    Yang, J X; Chaudhry, M T; Yao, J Y; Wang, S N; Zhou, B; Wang, M; Han, C Y; You, Y; Li, Y

    2018-04-01

    Quercetin, a polyphenolic flavonoid with diverse biological activities including anti-inflammatory and antiviral, inhibits lipid peroxidation, prevents oxidative injury and cell death. The purpose of the research was to investigate the effect of quercetin on productive performance, reproductive organs, hormones and apoptotic genes in laying hens between 37 and 45 weeks of age, because of the structure and oestrogenic activities similar to 17β-oestradiol. The trial was conducted using 240 Hessian laying hens (37 weeks old), housed in wire cages with two hens in each cage. These hens were randomly allotted to four treatments with six replicates, 10 hens in each replicate and fed with diets containing quercetin as 0, 0.2, 0.4 and 0.6 g/kg feed for 8 weeks. The results showed that dietary quercetin significantly increased (p feed-egg ratio was decreased (p  .05) on average egg weight and average daily feed intake. Compared with control, secretion of hormones, oestradiol (E 2 ) , progesterone (P4), follicle-stimulating hormone (FSH), luteinizing hormone (LH), insulin-like growth factors-1 (IGF-1) and growth hormone (GH), was found to be significantly higher (p  .05) by quercetin, whereas magnum index, isthmus index, magnum length, isthmus length and follicle numbers were significantly increased (p < .05) with quercetin supplementation. Additionally, expression of apoptotic genes was significantly (p < .05) up-regulated or down-regulated by quercetin. These results indicated that quercetin improved productive performance, and its mechanism may be due to the oestrogen-like activities of quercetin. © 2017 Blackwell Verlag GmbH.

  3. Tracers as invisible evidence - The transfer and persistence of flock fibres during a car exchange.

    Science.gov (United States)

    Slot, Ana; van der Weerd, Jaap; Roos, Martin; Baiker, Martin; Stoel, Reinoud D; Zuidberg, Matthijs C

    2017-06-01

    This study assessed the recovery of flock fibres used as a tracer in a car exchange scenario. Flock fibres were deposited onto a car seat (or model thereof) and their transfer and persistence was investigated after a real or simulated car exchange. The overall aim of this study was to achieve an optimal use of flock fibres as tracers, i.e. to be able to select a fit-for-purpose flock fibre, to be able to predict the amount of flock fibres to be recovered from crime related items, and to be able to use these numbers to exclude accidental uptake. The effect of a number of variables on the transfer and persistence of flock fibres was studied, including flock fibre length, car upholstery, and trousers material. Laboratory based experiments were undertaken first, followed by realistic field based experiments. The flock fibres were captured in a non-destructive manner through fluorescence photography. A Matlab algorithm enabled fast automated counting of flock fibres on the images. Results indicate that an initial rapid loss of flock fibres from garments may be expected as a result of moderate movement. Although the amount of flock fibres to be recovered is affected by the flock fibre length, the type of car upholstery, and the type of trousers materials (if frictional force is taken into consideration), large numbers of flock fibres have been recovered from all target materials throughout the transfer route. These numbers are higher than the amount of flock fibres recovered due to accidental uptake. In conclusion, flock fibres can serve as invisible evidence to reconstruct a series of events. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. The influence of the cage system and colonisation of Salmonella Enteritidis on the microbial gut flora of laying hens studied by T-RFLP and 454 pyrosequencing

    DEFF Research Database (Denmark)

    Nordentoft, Steen; Mølbak, Lars; Bjerrum, Lotte Bjerrum

    2011-01-01

    is not known, and different microbiota may demonstrate different resistance towards colonization with Salmonella. To investigate this, ileal and caecal samples from two experimental studies where laying hens were inoculated with Salmonella Enteritidis and housed in different systems (conventional cage...

  5. Cucker-Smale Flocking with Bounded Cohesive and Repulsive Forces

    Directory of Open Access Journals (Sweden)

    Qiang Song

    2013-01-01

    Full Text Available This paper proposes two Cucker-Smale-type flocking models by introducing both cohesive and repulsive forces to second-order multiagent systems. Under some mild conditions on the initial state of the flocking system, it is shown that the velocity consensus of the agents can be reached independent of the parameter which describes the decay of communication rates. In particular, the collision between any two agents can always be avoided by designing an appropriate bounded repulsive function based on the initial energy of the flock. Numerical examples are given to demonstrate the effectiveness of the theoretical analysis.

  6. The confusion effect when attacking simulated three-dimensional starling flocks.

    Science.gov (United States)

    Hogan, Benedict G; Hildenbrandt, Hanno; Scott-Samuel, Nicholas E; Cuthill, Innes C; Hemelrijk, Charlotte K

    2017-01-01

    The confusion effect describes the phenomenon of decreasing predator attack success with increasing prey group size. However, there is a paucity of research into the influence of this effect in coherent groups, such as flocks of European starlings ( Sturnus vulgaris ). Here, for the first time, we use a computer game style experiment to investigate the confusion effect in three dimensions. To date, computerized studies on the confusion effect have used two-dimensional simulations with simplistic prey movement and dynamics. Our experiment is the first investigation of the effects of flock size and density on the ability of a (human) predator to track and capture a target starling in a realistically simulated three-dimensional flock of starlings. In line with the predictions of the confusion effect, modelled starlings appear to be safer from predation in larger and denser flocks. This finding lends credence to previous suggestions that starling flocks have anti-predator benefits and, more generally, it suggests that active increases in density in animal groups in response to predation may increase the effectiveness of the confusion effect.

  7. Topological Sound and Flocking on Curved Surfaces

    Science.gov (United States)

    Shankar, Suraj; Bowick, Mark J.; Marchetti, M. Cristina

    2017-07-01

    Active systems on curved geometries are ubiquitous in the living world. In the presence of curvature, orientationally ordered polar flocks are forced to be inhomogeneous, often requiring the presence of topological defects even in the steady state because of the constraints imposed by the topology of the underlying surface. In the presence of spontaneous flow, the system additionally supports long-wavelength propagating sound modes that get gapped by the curvature of the underlying substrate. We analytically compute the steady-state profile of an active polar flock on a two-sphere and a catenoid, and show that curvature and active flow together result in symmetry-protected topological modes that get localized to special geodesics on the surface (the equator or the neck, respectively). These modes are the analogue of edge states in electronic quantum Hall systems and provide unidirectional channels for information transport in the flock, robust against disorder and backscattering.

  8. Prevalence of Coxiella burnetii in clinically healthy German sheep flocks

    Directory of Open Access Journals (Sweden)

    Hilbert Angela

    2012-03-01

    Full Text Available Abstract Background Current epidemiological data on the situation of Coxiella (C. burnetii infections in sheep are missing, making risk assessment and the implementation of counteractive measures difficult. Using the German state of Thuringia as a model example, the estimated sero-, and antigen prevalence of C. burnetii (10% and 25%, respectively was assessed at flock level in 39/252 randomly selected clinically healthy sheep flocks with more than 100 ewes and unknown abortion rate. Results The CHECKIT™ Q-fever Test Kit identified 11 (28% antibody positive herds, whereas real-time PCR revealed the presence of C. burnetii DNA in 2 (5% of the flocks. Multiple-locus variable number of tandem repeats analysis of 9 isolates obtained from one flock revealed identical profiles. All isolates contained the plasmid QpH1. Conclusions The results demonstrate that C. burnetii is present in clinically inconspicuous sheep flocks and sporadic flare-ups do occur as the notifications to the German animal disease reporting system show. Although C. burnetii infections are not a primary veterinary concern due to the lack of significant clinical impact on animal health (with the exception of goats, the eminent zoonotic risk for humans should not be underestimated. Therefore, strategies combining the interests of public and veterinary public health should include monitoring of flocks, the identification and culling of shedders as well as the administration of protective vaccines.

  9. Stability of model flocks in turbulent-like flow

    International Nuclear Information System (INIS)

    Khurana, Nidhi; Ouellette, Nicholas T

    2013-01-01

    We report numerical simulations of a simple model of flocking particles in the presence of an uncertain background environment. We consider two types of environmental perturbations: random noise applied separately to each particle, and spatiotemporally correlated ‘noise’ provided by a turbulent-like flow field. The effects of these two types of noise are very different; surprisingly, the applied flow field tends to destroy the global order of the flocking model even for vanishingly small flow amplitudes. Local order, however, is preserved in smaller sub-flocks, although their composition changes dynamically. Our results suggest that realistic perturbations must be considered in assessing the stability of models of collective animal behavior, and that random noise is not a sufficient proxy. (paper)

  10. Flock-based surveillance for lowpathogenic avian influenza virus in ...

    African Journals Online (AJOL)

    Flock-based surveillance for lowpathogenic avian influenza virus in commercial breeders and layers, southwest Nigeria. ... African Journal of Infectious Diseases ... Background: Flock surveillance systems for avian influenza (AI) virus play a critical role in countries where vaccination is not practiced so as to establish the ...

  11. Epidemiological characteristics of classical scrapie outbreaks in 30 sheep flocks in the United Kingdom.

    Directory of Open Access Journals (Sweden)

    K Marie McIntyre

    Full Text Available Most previous analyses of scrapie outbreaks have focused on flocks run by research institutes, which may not reflect the field situation. Within this study, we attempt to rectify this deficit by describing the epidemiological characteristics of 30 sheep flocks naturally-infected with classical scrapie, and by exploring possible underlying causes of variation in the characteristics between flocks, including flock-level prion protein (PrP genotype profile. In total, the study involved PrP genotype data for nearly 8600 animals and over 400 scrapie cases.We found that most scrapie cases were restricted to just two PrP genotypes (ARQ/VRQ and VRQ/VRQ, though two flocks had markedly different affected genotypes, despite having similar underlying genotype profiles to other flocks of the same breed; we identified differences amongst flocks in the age of cases of certain PrP genotypes; we found that the age-at-onset of clinical signs depended on peak incidence and flock type; we found evidence that purchasing infected animals is an important means of introducing scrapie to a flock; we found some evidence that flock-level PrP genotype profile and flock size account for variation in outbreak characteristics; identified seasonality in cases associated with lambing time in certain flocks; and we identified one case that was homozygous for phenylalanine at codon 141, a polymorphism associated with a very high risk of atypical scrapie, and 28 cases that were heterozygous at this codon.This paper presents the largest study to date on commercially-run sheep flocks naturally-infected with classical scrapie, involving 30 study flocks, more than 400 scrapie cases and over 8500 PrP genotypes. We show that some of the observed variation in epidemiological characteristics between farms is related to differences in their PrP genotype profile; although much remains unexplained and may instead be attributed to the stochastic nature of scrapie dynamics.

  12. The Detection of a Low Pathogenicity Avian Influenza Virus Subtype H9 Infection in a Turkey Breeder Flock in the United Kingdom.

    Science.gov (United States)

    Reid, Scott M; Banks, Jill; Ceeraz, Vanessa; Seekings, Amanda; Howard, Wendy A; Puranik, Anita; Collins, Susan; Manvell, Ruth; Irvine, Richard M; Brown, Ian H

    2016-05-01

    In April 2013, an H9N2 low pathogenicity avian influenza (LPAI) virus was isolated in a turkey breeder farm in Eastern England comprising 4966 birds. Point-of-lay turkey breeding birds had been moved from a rearing site and within 5 days had shown rapid onset of clinical signs of dullness, coughing, and anorexia. Three houses were involved, two contained a total of 4727 turkey hens, and the third housed 239 male turkeys. Around 50% of the hens were affected, whereas the male turkeys demonstrated milder clinical signs. Bird morbidity rose from 10% to 90%, with an increase in mortality in both houses of turkey hens to 17 dead birds in one house and 27 birds in the second house by day 6. The birds were treated with an antibiotic but were not responsive. Postmortem investigation revealed air sacculitis but no infraorbital sinus swellings or sinusitis. Standard samples were collected, and influenza A was detected. H9 virus infection was confirmed in all three houses by detection and subtyping of hemagglutinating agents in embryonated specific-pathogen-free fowls' eggs, which were shown to be viruses of H9N2 subtype using neuraminidase inhibition tests and a suite of real-time reverse transcription PCR assays. LPAI virus pathotype was suggested by cleavage site sequencing, and an intravenous pathogenicity index of 0.00 confirmed that the virus was of low pathogenicity. Therefore, no official disease control measures were required, and despite the high morbidity, birds recovered and were kept in production. Neuraminidase sequence analysis revealed a deletion of 78 nucleotides in the stalk region, suggesting an adaptation of the virus to poultry. Hemagglutinin gene sequences of two of the isolates clustered with a group of H9 viruses containing other contemporary European H9 strains in the Y439/Korean-like group. The closest matches to the two isolates were A/turkey/Netherlands/11015452/11 (H9N2; 97.9-98% nucleotide identity) and A/mallard/Finland/Li13384/10 (H9N2; 97

  13. Composition of Mix Species Foraging Flocks of Birds in Riverstan of Montane Region, Sri Lanka

    Directory of Open Access Journals (Sweden)

    W.G.D.D.M. Shermila

    2013-04-01

    Full Text Available Montane zone mixed-species bird flock system is distinct from that of low-land wet zone of SriLanka, although some species are present in both systems. The present study identified the mixed speciesflocks of birds in Riverstan at Knuckles Region, Sri Lanka. Monthly transect counts and opportunisticobservations were made between January and May, 2012. A total of 78 flocks and 27 bird species wereencountered at Riverstan during the study period. The flock size varied between 2 to 13 species and 4 to58 individuals. The mean number of species per flock was 6.03 ± 2.25 and the mean number ofindividuals in a flock was 18.41±9.87. The flock size was positively correlated with the number of speciespresent (r = 0.756, P <0.05. Grey-headed Canary Flycatcher was the most abundant species (mean2.68±1.02 birds per flocks while Sri Lanka White-eye was the most frequent species (mean 5.69±3.92birds per flocks. Grey-headed Canary Flycatcher and Sri Lanka Scimitar-babbler were the nuclear speciesin Riverstan. The leading species were Sri Lanka white-eye and Sri Lanka Yellow-eared Bulbul. Differentbird species used different heights within flocks.Keywords: Mixed-species flock, Nuclear species, Abundance, Foraging flocks

  14. Comparison of strategies for substantiating freedom from scrapie in a sheep flock.

    Science.gov (United States)

    Durand, Benoit; Martinez, Marie-José; Calavas, Didier; Ducrot, Christian

    2009-04-30

    The public health threat represented by a potential circulation of bovine spongiform encephalopathy agent in sheep population has led European animal health authorities to launch large screening and genetic selection programmes. If demonstrated, such a circulation would have dramatic economic consequences for sheep breeding sector. In this context, it is important to evaluate the feasibility of qualification procedures that would allow sheep breeders demonstrating their flock is free from scrapie. Classical approaches, based on surveys designed to detect disease presence, do not account for scrapie specificities: the genetic variations of susceptibility and the absence of live diagnostic test routinely available. Adapting these approaches leads to a paradoxical situation in which a greater amount of testing is needed to substantiate disease freedom in genetically resistant flocks than in susceptible flocks, whereas probability of disease freedom is a priori higher in the former than in the latter. The goal of this study was to propose, evaluate and compare several qualification strategies for demonstrating a flock is free from scrapie. A probabilistic framework was defined that accounts for scrapie specificities and allows solving the preceding paradox. Six qualification strategies were defined that combine genotyping data, diagnostic tests results and flock pedigree. These were compared in two types of simulated flocks: resistant and susceptible flocks. Two strategies allowed demonstrating disease freedom in several years, for the majority of simulated flocks: a strategy in which all the flock animals are genotyped, and a strategy in which only founders animals are genotyped, the flock pedigree being known. In both cases, diagnostic tests are performed on culled animals. The less costly strategy varied according to the genetic context (resistant or susceptible) and to the relative costs of a genotyping exam and of a diagnostic test. This work demonstrates that

  15. Topological Sound and Flocking on Curved Surfaces

    Directory of Open Access Journals (Sweden)

    Suraj Shankar

    2017-09-01

    Full Text Available Active systems on curved geometries are ubiquitous in the living world. In the presence of curvature, orientationally ordered polar flocks are forced to be inhomogeneous, often requiring the presence of topological defects even in the steady state because of the constraints imposed by the topology of the underlying surface. In the presence of spontaneous flow, the system additionally supports long-wavelength propagating sound modes that get gapped by the curvature of the underlying substrate. We analytically compute the steady-state profile of an active polar flock on a two-sphere and a catenoid, and show that curvature and active flow together result in symmetry-protected topological modes that get localized to special geodesics on the surface (the equator or the neck, respectively. These modes are the analogue of edge states in electronic quantum Hall systems and provide unidirectional channels for information transport in the flock, robust against disorder and backscattering.

  16. Detection of antibodies against Chlamydophila abortus in Costa Rican sheep flocks

    Directory of Open Access Journals (Sweden)

    R. Villagra-Blanco

    2015-09-01

    Full Text Available A total of 359 sheep samples from 15 flocks were analyzed for the presence of antibodies against Chlamydophila abortus using a commercial Enzyme linked Immunosorbent Assay (ELISA. Antibodies were detected in 19 (5.29% sheep from 12 (80% flocks. Seropositive animals were found in all analyzed regions (Central, Chorotega, Atlantic Huetar, North Huetar and Central Pacific determining prevalence between 0.28% and 4.4%, and intra-flock positivity between 3.7% and 25.0%. The survey revealed two risk factors associated with seropositivity; introducing animals (males and females, embryos, or semen from other farms or from abroad without any sanitary certification, and flocks not having quarantine areas or separated boxes for diseased animals. No clinical signs of disease were observed in positive seroreactors. C. abortus seems to be present in Costa Rica in a very low prevalence in sheep flocks. Further studies, to isolate the bacteria are required. Finally, implementation of control measures to prevent the spread of C. abortus is recommended.

  17. Detection of antibodies against Chlamydophila abortus in Costa Rican sheep flocks

    Science.gov (United States)

    Villagra-Blanco, R.; Dolz, G.; Montero-Caballero, D.; Romero-Zúñiga, J.J.

    2015-01-01

    A total of 359 sheep samples from 15 flocks were analyzed for the presence of antibodies against Chlamydophila abortus using a commercial Enzyme linked Immunosorbent Assay (ELISA). Antibodies were detected in 19 (5.29%) sheep from 12 (80%) flocks. Seropositive animals were found in all analyzed regions (Central, Chorotega, Atlantic Huetar, North Huetar and Central Pacific) determining prevalence between 0.28% and 4.4%, and intra-flock positivity between 3.7% and 25.0%. The survey revealed two risk factors associated with seropositivity; introducing animals (males and females), embryos, or semen from other farms or from abroad without any sanitary certification, and flocks not having quarantine areas or separated boxes for diseased animals. No clinical signs of disease were observed in positive seroreactors. C. abortus seems to be present in Costa Rica in a very low prevalence in sheep flocks. Further studies, to isolate the bacteria are required. Finally, implementation of control measures to prevent the spread of C. abortus is recommended. PMID:26623377

  18. Carry-over of thermophilic Campylobacter spp. between sequential and adjacent poultry flocks.

    Science.gov (United States)

    Alter, Thomas; Weber, Rita Margarete; Hamedy, Ahmad; Glünder, Gerhard

    2011-01-10

    Nineteen flocks of four poultry species were monitored at a veterinary field station to investigate the distribution and spread of Campylobacter genotypes between sequential and adjacent flocks. Caecal and liver samples were obtained at frequent intervals from birds of all flocks and examined for Campylobacter. Amplified fragment length polymorphism (AFLP) analysis was performed to genotype Campylobacter isolates. Of the 1643 caecal and liver samples investigated, 452 (27.5%) caecal samples and 11 (0.7%) liver samples contained Campylobacter. Of the caecal isolates 76.3% were identified as Campylobacter jejuni and 23.7% were identified as Campylobacter coli. Poultry flocks were largely colonized by more than one AFLP type and an intense exchange of Campylobacter genotypes between different poultry flocks occurred. These findings indicate that multiple genotypes can constitute the Campylobacter population within single poultry flocks, hinting to different sources of exposure and/or genetic drifts within the Campylobacter population. Nevertheless, in most flocks single Campylobacter genotypes predominated. Some strains superseded others resulting in colonization by successive Campylobacter genotypes during the observation period. In conclusion, the data demonstrate that the large genetic diversity of Campylobacter must be considered in epidemiological evaluations and microbial risk assessments of Campylobacter in poultry. Copyright © 2010 Elsevier B.V. All rights reserved.

  19. Survey of egg farmers regarding the ban on conventional cages in the EU and their opinion of alternative layer housing systems in Flanders, Belgium.

    Science.gov (United States)

    Stadig, L M; Ampe, B A; Van Gansbeke, S; Van den Bogaert, T; D'Haenens, E; Heerkens, J L T; Tuyttens, F A M

    2016-03-01

    On 1 January 2012, conventional cages for laying hens were banned in the European Union (EU); all egg farmers must now use alternative hen housing systems. In total, 218 Flemish egg farmers were surveyed in 2013 to 2014 regarding which housing systems they currently use, their degree of satisfaction with the system, and how they experienced the transition from conventional cages to an alternative system. The response rate was 58.3% (127 respondents). Of these, 43 (33.9%) were no longer active as an egg farmer, mainly due to the ban on conventional cages. The respondents who were active as egg farmers both before and after the transition (84, 66.1%) mainly judged the ban as negative for their own finances and for the competitive position of the Belgian egg industry, but were neutral or positive regarding the general consequences for their own business. Most respondents' hens were housed in either aviary systems (47.7%) or in alternative cage systems (38.2%). When choosing a new system, the fit into the farm and consumer demand were the most important factors. Consumer demand was the main reason for choosing a system with free-range access. In general, egg farmers were satisfied with the system they chose, although this differs between systems. When asked to compare the alternative systems to conventional cages, alternatives were judged to be better for hen welfare and consumer demand, but similar or worse for all other aspects, especially labor. Egg farmers previously using conventional cages judged alternative systems more negatively than those who had no prior experience with conventional cages. Farmers who had experience with free-range systems judged these more positively than those without this experience, e.g., for egg consumer demand, profitability, and hen welfare. These results can possibly be extrapolated to other EU countries in which conventional cages were the most common housing system until 2012, and lessons can be drawn from the farmers' experiences

  20. Assessment of lighting needs by W-36 laying hens via preference test.

    Science.gov (United States)

    Ma, H; Xin, H; Zhao, Y; Li, B; Shepherd, T A; Alvarez, I

    2016-04-01

    Light intensity, spectrum and pattern may affect laying hen behaviors and production performance. However, requirements of these lighting parameters from the hens' standpoint are not fully understood. This study was conducted to investigate hens' needs for light intensity and circadian rhythm using a light tunnel with five identical compartments each at a different fluorescent light intensity of hens were able to move freely among the respective compartments. A group of four W-36 laying hens (23 to 30 weeks of age) were tested each time, and six groups or replicates were conducted. Behaviors of the hens were continuously recorded, yielding data on daily time spent, daily feed intake, daily feeding time, and eggs laid under each light intensity and daily inter-compartment movement. The results show that the hens generally spent more time in lower light intensities. Specifically, the hens spent 6.4 h (45.4%) at 5 lux, 3.0 h (22.1%) at 15 lux, 3.1 h (22.2%) at 30 lux and 1.5 h (10.3%) at 100 lux under light condition; and an accumulation of 10.0 h in darkness (feed intake (87.3 g/hen) among the different light conditions mirrored the trend of time spent in the respective light intensity, that is, highest at 5 lux (28.4 g/hen, 32.5% daily total) and lowest at 100 lux (5.8 g/hen, 6.7%). Hen-day egg production rate was 96.0%. Most of the eggs were laid in hens. Further studies to assess or verify welfare and performance responses of the hens to the preferred lighting conditions and rhythm over extended periods are recommended.

  1. Turkey-hen amino acid composition of brain and eyes

    International Nuclear Information System (INIS)

    Adeyeye, E.I.

    2015-01-01

    The amino acids composition of the brain and eyes of the mature Turkey-hen (Meleagris gallopavo L.), were determined on dry weight basis. Total essential amino acids ranged from 35.1-36.0 g/100 g as 49.5-49.8% of the total amino acids. The amino acid score showed that lysine ranged from 0.76-0.91 (on whole hen.s egg comparison), 0.85-1.03 (on provisional essential amino acid scoring pattern), and 0.81-0.98 (on suggested requirement of the essential amino acid of a preschool child). The predicted protein efficiency ratio was 1.94-2.41, whilst essential amino acid index range was 1.06-1.08 and the calculated isoelectric point range was 3.97-4.18. The correlation coefficient (rxy) was positively high and significant at r = 0.01 for the total amino acids, amino acid scores (on the whole hen.s egg comparisons made) and the isoelectric point. On the whole, the eyes were better in 12/18 or 66.7% parameters of the amino acids than the brain of Turkey-Hen. (author)

  2. The influence of hen age on fatty acid composition of commercial eggs

    Directory of Open Access Journals (Sweden)

    Tina Lešić

    2017-01-01

    Full Text Available The aim of this study was to investigate the nutritional composition of commercial eggs from Lohman Brown hens through fat and fatty acid content analysis, as well as to evaluate the effect of hen age on the above parameters. Egg samples (n=108 were collected every two weeks from 21- to 55- week old hens during the 2015/2016 autumn/winter period. The results revealed significant differences in fatty acid composition dependent on hen age (p 0.05. The total polyunsaturated fatty acid (PUFA content was statistically significantly higher in eggs laid by 55- week old hens as compared to those laid by 21- week old hens. The n-6/n-3 and PUFA/SFA ratios were more favourable in the elder hens. In general, the results revealed hen ageing-based variations in fatty acid composition of their eggs, in particular in the representation of linoleic (LA, alpha-linolenic (ALA and arachidonic acid (AA, for which statistically significant hen age-based differences were found.

  3. Pasture, multi-enzymes, benzoic acid and essential oils positively influence performance, intestinal organ weight and egg quality in free-range laying hens.

    Science.gov (United States)

    Iqbal, Z; Roberts, J; Perez-Maldonado, R A; Goodarzi Boroojeni, F; Swick, R A; Ruhnke, I

    2018-04-01

    1. The objective of this study was to investigate the effect of range type, multi-enzyme applications, and a combination of benzoic acid (BA) and essential oils (EO) on the productive performance, organ weight and egg quality of free-range laying hens. 2. Three hundred laying hens were evaluated for the short-term (6 weeks) and long-term (12 weeks) effects of range type (G = no pasture, P = pasture) and feed additives (T1 = control; T2 = betaglucanase/pectinase/protease; T3 = BA/EO). Body weight, feed intake (FI), feed conversion ratio (FCR), egg production (EP), digestive organ weight, and egg quality (EQ) were evaluated. Data were analysed using SPSS 2.2 in a 2×2×3 factorial arrangement. 3. Hens that ranged on pasture were significantly heavier (2043 g vs. 1996 g; p ranged on gravel. Hens fed T2 were significantly heavier (2050 g) compared to hens fed T1 (2005 g) or T3 (2008 g). Organ weights (gizzard, liver and pancreas) were significantly heavier in hens ranged on pasture (16.8 g/kg BW, 22.3 g/kg BW and 1.89 g/kg BW, respectively) compared to hens ranged on gravel (14.2 g/kg BW, 21.7 g/kg BW and 1.83 g/kg BW, respectively). Over time, body weight (1970-2070 g; p < 0.001) and egg weight (59.5-62.8 g; p < 0.001) increased, FI (123-120 g; p = 0.024) was reduced and FCR (2.36-2.10; p = 0.002) improved 4. In conclusion, hens housed on pasture and fed multi-enzyme supplemented diets had significantly heavier body weight and produced heavier eggs with darker yolk colour. Pasture intake and enzyme supplementation increased digestive organ weight significantly.

  4. A data envelope analysis to assess factors affecting technical and economic efficiency of individual broiler breeder hens.

    Science.gov (United States)

    Romero, L F; Zuidhof, M J; Jeffrey, S R; Naeima, A; Renema, R A; Robinson, F E

    2010-08-01

    This study evaluated the effect of feed allocation and energetic efficiency on technical and economic efficiency of broiler breeder hens using the data envelope analysis methodology and quantified the effect of variables affecting technical efficiency. A total of 288 Ross 708 pullets were placed in individual cages at 16 wk of age and assigned to 1 of 4 feed allocation groups. Three of them had feed allocated on a group basis with divergent BW targets: standard, high (standard x 1.1), and low (standard x 0.9). The fourth group had feed allocated on an individual bird basis following the standard BW target. Birds were classified in 3 energetic efficiency categories: low, average, and high, based on estimated maintenance requirements. Technical efficiency considered saleable chicks as output and cumulative ME intake and time as inputs. Economic efficiency of feed allocation treatments was analyzed under different cost scenarios. Birds with low feed allocation exhibited a lower technical efficiency (69.4%) than standard (72.1%), which reflected a reduced egg production rate. Feed allocation of the high treatment could have been reduced by 10% with the same chick production as the standard treatment. The low treatment exhibited reduced economic efficiency at greater capital costs, whereas high had reduced economic efficiency at greater feed costs. The average energetic efficiency hens had a lower technical efficiency in the low compared with the standard feed allocation. A 1% increment in estimated maintenance requirement changed technical efficiency by -0.23%, whereas a 1% increment in ME intake had a -0.47% effect. The negative relationship between technical efficiency and ME intake was counterbalanced by a positive correlation of ME intake and egg production. The negative relationship of technical efficiency and maintenance requirements was synergized by a negative correlation of hen maintenance and egg production. Economic efficiency methodologies are effective

  5. 9 CFR 146.23 - Terminology and classification; flocks and products.

    Science.gov (United States)

    2010-01-01

    ... layers through routine serological surveillance of each participating commercial table-egg layer flock. A... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR COMMERCIAL POULTRY Special Provisions for Commercial Table-Egg Layer Flocks § 146.23 Terminology and classification...

  6. Worm control practice against gastro-intestinal parasites in Norwegian sheep and goat flocks

    Science.gov (United States)

    2011-01-01

    Background Anthelmintic treatment is the most common way of controlling nematode infections in ruminants. However, several countries have reported anthelmintic resistance (AR), representing a limitation for sustainable small ruminant production. The knowledge regarding worm control management represents a baseline to develop a guideline for preventing AR. The aim of the present study was therefore to improve our knowledge about the worm control practices in small ruminant flocks in Norway. Methods A questionnaire survey regarding worm control practices was performed in small ruminant flocks in Norway. Flocks were selected from the three main areas of small ruminant farming, i.e. the coastal, inland and northern areas. A total of 825 questionnaires, comprising 587 sheep flocks (return rate of 51.3%) and 238 goat flocks (52.6%) were included. Results The results indicated that visual appraisal of individual weight was the most common means of estimating the anthelmintic dose used in sheep (78.6%) and goat (85.1%) flocks. The mean yearly drenching rate in lambs and ewes were 2.5 ± 1.7 and 1.9 ± 1.1, respectively, whereas it was 1.0 (once a year) in goats. However, these figures were higher in sheep in the coastal area with a rate of 3.4 and 2.2 in lambs and ewes, respectively. Benzimidazoles were the predominant anthelmintic class used in sheep flocks (64.9% in 2007), whereas benzimidazoles and macrocyclic lactones were both equally used in dairy goat flocks. In the period of 2005-2007, 46.3% of the sheep flocks never changed the anthelmintic class. The dose and move strategy was practiced in 33.2% of the sheep flocks. Conclusions The present study showed that inaccurate weight calculation gives a risk of under-dosing in over 90% of the sheep and goat flocks in Norway. Taken together with a high treatment frequency in lambs, a lack of anthelmintic class rotation and the common use of a dose-and-move strategy, a real danger for development of anthelmintic resistance

  7. Worm control practice against gastro-intestinal parasites in Norwegian sheep and goat flocks

    Directory of Open Access Journals (Sweden)

    Vatn Synnøve

    2011-05-01

    Full Text Available Abstract Background Anthelmintic treatment is the most common way of controlling nematode infections in ruminants. However, several countries have reported anthelmintic resistance (AR, representing a limitation for sustainable small ruminant production. The knowledge regarding worm control management represents a baseline to develop a guideline for preventing AR. The aim of the present study was therefore to improve our knowledge about the worm control practices in small ruminant flocks in Norway. Methods A questionnaire survey regarding worm control practices was performed in small ruminant flocks in Norway. Flocks were selected from the three main areas of small ruminant farming, i.e. the coastal, inland and northern areas. A total of 825 questionnaires, comprising 587 sheep flocks (return rate of 51.3% and 238 goat flocks (52.6% were included. Results The results indicated that visual appraisal of individual weight was the most common means of estimating the anthelmintic dose used in sheep (78.6% and goat (85.1% flocks. The mean yearly drenching rate in lambs and ewes were 2.5 ± 1.7 and 1.9 ± 1.1, respectively, whereas it was 1.0 (once a year in goats. However, these figures were higher in sheep in the coastal area with a rate of 3.4 and 2.2 in lambs and ewes, respectively. Benzimidazoles were the predominant anthelmintic class used in sheep flocks (64.9% in 2007, whereas benzimidazoles and macrocyclic lactones were both equally used in dairy goat flocks. In the period of 2005-2007, 46.3% of the sheep flocks never changed the anthelmintic class. The dose and move strategy was practiced in 33.2% of the sheep flocks. Conclusions The present study showed that inaccurate weight calculation gives a risk of under-dosing in over 90% of the sheep and goat flocks in Norway. Taken together with a high treatment frequency in lambs, a lack of anthelmintic class rotation and the common use of a dose-and-move strategy, a real danger for development of

  8. Prevalence of and risk factors associated with ovine progressive pneumonia in Wyoming sheep flocks.

    Science.gov (United States)

    Gerstner, Shelley; Adamovicz, Jeffrey J; Duncan, John V; Laegreid, William W; Marshall, Katherine L; Logan, James R; Schumaker, Brant A

    2015-10-15

    To determine the prevalence of antibodies against small ruminant lentivirus (SRLV), the causative agent of ovine progressive pneumonia (OPP), and to identify risk factors associated with OPP in Wyoming sheep flocks. Cross-sectional study. 1,415 sheep from 54 flocks in Wyoming. Flocks were surveyed as part of the National Animal Health Monitoring System (NAHMS) 2011 sheep study. Serum samples obtained from sheep in Wyoming were analyzed for anti-SRLV antibodies by use of a competitive-inhibition ELISA. The prevalence of seropositive animals overall and within each flock was calculated. Respective associations between flock OPP status and various demographic and management variables were assessed. The estimated prevalence of sheep seropositive for anti-SRLV antibodies and OPP-infected flocks in Wyoming was 18.0% and 47.5%, respectively. Within OPP-infected flocks, the prevalence of seropositive sheep ranged from 3.9% to 96%. Flocks maintained on nonfenced range were more likely to be infected with OPP than were flocks maintained on fenced range (OR, 3.4; 95% confidence interval, 1.1 to 10.7). The estimated prevalence of OPP-infected flocks in Wyoming did not vary substantially from that at the regional or national level reported in the NAHMS 2001 sheep study. Compared with results of the NAHMS 2011 sheep study, Wyoming producers were more familiar with OPP than were other US sheep producers, but only 61% of Wyoming producers surveyed reported being very or somewhat familiar with the disease. Results indicated that OPP is prevalent in many Wyoming sheep flocks, which suggested that continued efforts are necessary to increase producer knowledge about the disease and investigate practices to minimize economic losses associated with OPP.

  9. Prevalence and risk factors for Salmonella spp. colonization in broiler flocks in Shiraz, southern Iran

    Directory of Open Access Journals (Sweden)

    Maryam Ansari-Lari

    2014-04-01

    Full Text Available Salmonella spp. are important food borne pathogens worldwide that frequently infect poultry flocks. This cross-sectional study was conducted to determine the prevalence of Salmonella spp. colonization in broiler flocks in Shiraz (southern Iran and to find the possible association of infection status with some potential risk factors including vaccination program and use of antibiotics. During October 2009 to April 2010, a total of 40 broiler flocks were selected in slaughterhouse and 20 cloacae contents were collected from each flock. Every five cloacae contents were pooled and investigated for Salmonella spp. using appropriate culture methods. The flock was considered positive if any of the pooled samples turned positive in culture. Statistical analysis was performed using multiple logistic regression. Nine out of 40 flocks (22.50%, 95% CI: 9-36 were positive for Salmonella spp. colonization. Nearly 75.00% of flock owners reported that they used antibiotics during production period, more frequently fluoroquinolones, combination of trimethoprim-sulfonamides (TMP/SU and tetracycline. Nearly 60.00% of the flocks which had used TMP/SU were positive for Salmonella spp. compared with 10.00% of the flocks which did not use this antibiotic (p = 0.006. Increasing flock age was associated with a decreased chance of Salmonella spp. detection (p = 0.003. In flocks which received infectious bronchitis vaccine, 36.00% were positive for Salmonella spp. whereas this was 15.00% for flocks which did not receive this vaccine (p = 0.08. Careful monitoring of antibiotics use and further studies to determine the most appropriate vaccination program in the field is recommended.

  10. Evaluation of production parameters and nutrient utilization of hens ...

    African Journals Online (AJOL)

    Two hundred and fifty Babcock hens in their 10th week of lay were divided into 5 groups of 50 hens each and randomly assigned to the 5 treatment rations in a completely randomized design (CRD). Data were collected on average final weight, body weight change, average feed intake, average hen-day lay, average egg ...

  11. Nest sharing under semi-natural conditions in laying hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch

    2012-01-01

    problems to laying hens, and egg production may also be negatively affected. Understanding what causes this difference in nest location selection may provide solutions to the problems associated with simultaneous nest sharing. The aims were to investigate whether a commercial strain of laying hens normally...... daily of each nest with regard to number of eggs, position, and materials used. On five mornings nesting behaviour was observed. Nest sharing occurred on all but the first 5 days of egg-laying. The majority of hens (n = 14) chose to visit an occupied nest at least once, but no hens exclusively used...

  12. Age-Related Variations in Intestinal Microflora of Free-Range and Caged Hens.

    Science.gov (United States)

    Cui, Yizhe; Wang, Qiuju; Liu, Shengjun; Sun, Rui; Zhou, Yaqiang; Li, Yue

    2017-01-01

    Free range feeding pattern puts the chicken in a mixture of growth materials and enteric bacteria excreted by nature, while it is typically unique condition materials and enteric bacteria in commercial caged hens production. Thus, the gastrointestinal microflora in two feeding patterns could be various. However, it remains poorly understood how feeding patterns affect development and composition of layer hens' intestinal microflora. In this study, the effect of feeding patterns on the bacteria community in layer hens' gut was investigated using free range and caged feeding form. Samples of whole small intestines and cecal digesta were collected from young hens (8-weeks) and mature laying hens (30-weeks). Based on analysis using polymerase chain reaction-denaturing gradient gel electrophoresis and sequencing of bacterial 16S rDNA gene amplicons, the microflora of all intestinal contents were affected by both feeding patterns and age of hens. Firmicutes, Bacteroidetes, Actinobacteria, Proteobacteria, and Fusobacteria were the main components. Additionally, uncultured environmental samples were found too. There were large differences between young hens and adult laying hens, the latter had more Firmicutes and Bacteroidetes, and bacterial community is more abundant in 30-weeks laying hens of all six phyla than 8-weeks young hens of only two phyla. In addition, the differences were also observed between free range and caged hens. Free range hens had richer Actinobacteria, Bacteroidetes, and Proteobacteria. Most of strains found were detected more abundant in small intestines than in cecum. Also the selected Lactic acid bacteria from hens gut were applied in feed and they had beneficial effects on growth performance and jejunal villus growth of young broilers. This study suggested that feeding patterns have an importance effect on the microflora composition of hens, which may impact the host nutritional status and intestinal health.

  13. The Use of Radiation to Suppress the Impact of Aflatoxin B 1 Contaminated Diets on the Productive Performance and Immunological Response of Laying Hens

    International Nuclear Information System (INIS)

    Farag, M.D.H.; AbdulAzeem, A.M.; Abdalla, E.A.; Ahmed, N.A.H.

    2017-01-01

    Detoxification of aflatoxin (AF) from contaminated food and feed stuffs remains a major problem and there is a great demand for an effective decontamination technology. A recent approach to the problem is irradiation of food to destroy AFB 1 .In this study, the reduction of aflatoxicosis in Golden Montazah (GM ) local laying hens that were fed contaminated diets, was treated using gamma (γ) irradiation. This research included two phases: The first one (experimental duration) in which laying hens were fed (3 week s) on artificially contaminated diets with 0.2 mg AFB 1 kg −1 and subjected to 0, 10, 20 and 30 k Gy gamma irradiation. The second phase (recovery duration), the hens were fed non-contaminated diets for another 3 weeks to study the withdrawal time required for bringing back the flock to its normal production. After six week s of feeding, the hens were slaughtered. The significant adverse effect of AFB 1 on the feed intake, egg mass, feed conversion ratio (FCR), egg production, egg quality (shell weight, egg width, shell thickness and egg shape index), internal egg quality (albumin height, yolk height, yolk weight, albumin index, yolk index and haugh unit), relative organ weights (kidney, spleen and heart), and residues of AFB1 in eggs, breast muscle and organs (kidney, spleen and heart) were evaluated and hematological parameters ( Hemoglobin, total count of red and white blood cells as well as some differential counts of leucocytes (lymphocyte and heterophil percentages) and the immune response to Newcastle Disease Virus (NDV) and Infectious Bronchitis Virus (IBV) were also evaluated. The result ts showed that γ-radiation significantly (P<0.05) reduced the deleterious effects of AFB 1 on feed intake, egg mass and FCR ratio and the reduction was proportional with irradiation dose. Asignificant increase was observed in the mean egg production of laying hens fed on diets contaminated with AFB 1 and irradiated with γ-rays at 10, 20 and 30 k Gy, compared

  14. Utilization of a novel autologous killed tri-vaccine (serogroups B [Typhimurium], C [Mbandaka] and E [Orion]) for Salmonella control in commercial poultry breeders.

    Science.gov (United States)

    Pavic, Anthony; Groves, Peter J; Cox, Julian M

    2010-02-01

    An autologous killed trivalent vaccine (3x10(8) colony-forming units [CFU]), based on three Salmonella serovars (Typhimurium - serogroup B, Mbandaka - serogroup C, and Orion - serogroup E) prevalent in the flocks of Australian poultry companies, was developed using Salenvac techniques. At 20 weeks, hens vaccinated at 12 and 17 weeks as well as non-vaccinated hens were challenged (250 microl of 10(7) CFU) with autologous and heterologous serovars belonging to serogroup B (Typhimurium and Agona), serogroup C (Mbandaka and Infantis) and serogroup E (Orion and Zanzibar). Overall, vaccination resulted in a significant difference in carriage of Salmonella between non-vaccinated and vaccinated commercial Cobb hens (P 0.05) could be determined for serogroup E. All vaccinated flocks produced a significant antibody response (P<0.001) to the S. Typhimurium vaccine strain, measured using a S. Typhimurium enzyme-linked immunosorbent assay (Guildhay), which peaked at 20 weeks of age, with 39% of the hens positive. Maternal antibodies were detected in 16% of the yolks from eggs produced by these flocks. There was a significant difference after challenge with Salmonella (P <0.05) among 1-day-old chicks from vaccinated versus non-vaccinated parents, when challenged using 10(4) CFU but not when challenged with 10(8) CFU. The success of this trial resulted in the incorporation of this vaccine into a Salmonella control system in commercial broiler breeder production.

  15. Flocking algorithm for autonomous flying robots.

    Science.gov (United States)

    Virágh, Csaba; Vásárhelyi, Gábor; Tarcai, Norbert; Szörényi, Tamás; Somorjai, Gergő; Nepusz, Tamás; Vicsek, Tamás

    2014-06-01

    Animal swarms displaying a variety of typical flocking patterns would not exist without the underlying safe, optimal and stable dynamics of the individuals. The emergence of these universal patterns can be efficiently reconstructed with agent-based models. If we want to reproduce these patterns with artificial systems, such as autonomous aerial robots, agent-based models can also be used in their control algorithms. However, finding the proper algorithms and thus understanding the essential characteristics of the emergent collective behaviour requires thorough and realistic modeling of the robot and also the environment. In this paper, we first present an abstract mathematical model of an autonomous flying robot. The model takes into account several realistic features, such as time delay and locality of communication, inaccuracy of the on-board sensors and inertial effects. We present two decentralized control algorithms. One is based on a simple self-propelled flocking model of animal collective motion, the other is a collective target tracking algorithm. Both algorithms contain a viscous friction-like term, which aligns the velocities of neighbouring agents parallel to each other. We show that this term can be essential for reducing the inherent instabilities of such a noisy and delayed realistic system. We discuss simulation results on the stability of the control algorithms, and perform real experiments to show the applicability of the algorithms on a group of autonomous quadcopters. In our case, bio-inspiration works in two ways. On the one hand, the whole idea of trying to build and control a swarm of robots comes from the observation that birds tend to flock to optimize their behaviour as a group. On the other hand, by using a realistic simulation framework and studying the group behaviour of autonomous robots we can learn about the major factors influencing the flight of bird flocks.

  16. Selected pharmacokinetic parameters for Cefovecin in hens and green iguanas.

    Science.gov (United States)

    Thuesen, L R; Bertelsen, M F; Brimer, L; Skaanild, M T

    2009-12-01

    The third generation cephalosporin cefovecin has been shown to have an exceptionally long elimination half-life in dogs and cats, making it suitable for antibacterial treatment with a 14-day dosing interval in these species. Pharmacokinetic parameters for cefovecin were investigated in juvenile hens and green iguanas, following subcutaneous injections with 10 mg cefovecin/kg bodyweight. Preliminary studies in eight additional species of birds and reptiles were performed and results were compared with the parameters found in hens and green iguanas. The kinetics were characterized by rapid absorption with peak plasma concentration of 6 +/- 2 microg/mL in hens and 35 +/- 12 microg/mL in green iguanas. The mean plasma half-life for cefovecin was 0.9 +/- 0.3 h for hens and 3.9 h in green iguanas. Volume of distribution was 1.6 +/- 0.5 L/kg for hens and 0.3 L/kg for green iguanas and clearance was 1252 +/- 185 mL.h/kg for hens and 53 mL.h/kg for green iguanas. Results from preliminary studies did not differ notably from those seen in hens and green iguanas. Cefovecin is not suitable for the treatment of bacterial infections with a 14-day dosing interval in hens or green iguanas and seems not to be in a number of other bird and retile species either.

  17. An Improved Fast Flocking Algorithm with Obstacle Avoidance for Multiagent Dynamic Systems

    Directory of Open Access Journals (Sweden)

    Jialiang Wang

    2014-01-01

    Full Text Available Flocking behavior is a common phenomenon in nature, such as flocks of birds and groups of fish. In order to make the agents effectively avoid obstacles and fast form flocking towards the direction of destination point, this paper proposes a fast multiagent obstacle avoidance (FMOA algorithm. FMOA is illustrated based on the status of whether the flocking has formed. If flocking has not formed, agents should avoid the obstacles toward the direction of target. If otherwise, these agents have reached the state of lattice and then these agents only need to avoid the obstacles and ignore the direction of target. The experimental results show that the proposed FMOA algorithm has better performance in terms of flocking path length. Furthermore, the proposed FMOA algorithm is applied to the formation flying of quad-rotor helicopters. Compared with other technologies to perform the localization of quad-rotor helicopter, this paper innovatively constructs a smart environment by deploying some wireless sensor network (WSN nodes using the proposed localization algorithm. Finally, the proposed FMOA algorithm is used to conduct the formation flying of these quad-rotor helicopters in the smart environment.

  18. 9 CFR 145.63 - Terminology and classification; flocks and products.

    Science.gov (United States)

    2010-01-01

    ... Terminology and classification; flocks and products. Participating flocks, and the eggs and baby poultry... examination monitoring program of hatcher debris or eggs for ostriches, emus, rheas, or cassowaries acceptable... made that can be traced to a source in that State, that uses a bacteriological examination monitoring...

  19. Effects of Furnished Cage Type on Behavior and Welfare of Laying Hens.

    Science.gov (United States)

    Li, Xiang; Chen, Donghua; Li, Jianhong; Bao, Jun

    2016-06-01

    This study was conducted to compare the effects of layout of furniture (a perch, nest, and sandbox) in cages on behavior and welfare of hens. Two hundred and sixteen Hyline Brown laying hens were divided into five groups (treatments) with four replicates per group: small furnished cages (SFC), medium furnished cages type I (MFC-I), medium furnished cages type II (MFC-II), and medium furnished cages type III (MFC-III) and conventional cages (CC). The experiment started at 18 week of age and finished at 52 week of age. Hens' behaviors were filmed during the following periods: 8:00 to 10:00; 13:00 to 14:00; 16:00 to 17:00 on three separate days and two hens from each cage were measured for welfare parameters at 50 wk of age. The results showed that feeding and laying of all hens showed no effect by cage type (p>0.05), and the hens in the furnished cages had significantly lower standing and higher walking than CC hens (p0.05). The hens in MFC-I, -II, and -III showed a significant higher socializing behavior than SFC and CC (p<0.05). The lowest perching was for the hens in SFC and the highest perching found for the hens in MFC-III. Overall, the hens in CC showed poorer welfare conditions than the furnished cages, in which the feather condition score, gait score and tonic immobility duration of the hens in CC was significantly higher than SFC, MFC-I, MFC-II, and MFC-III (p<0.05). In conclusion, the furnished cage design affected both behavior and welfare states of hens. Overall, MFC-III cage design was better than SFC, MFC-I, and MFC-II cage designs.

  20. How many dissenters does it take to disorder a flock?

    Science.gov (United States)

    Yllanes, D.; Leoni, M.; Marchetti, M. C.

    2017-10-01

    We consider the effect of introducing a small number of non-aligning agents in a well-formed flock. To this end, we modify a minimal model of active Brownian particles with purely repulsive (excluded volume) forces to introduce an alignment interaction that will be experienced by all the particles except for a small minority of ‘dissenters’. We find that even a very small fraction of dissenters disrupts the flocking state. Strikingly, these motile dissenters are much more effective than an equal number of static obstacles in breaking up the flock. For the studied system sizes we obtain clear evidence of scale invariance at the flocking-disorder transition point and the system can be effectively described with a finite-size scaling formalism. We develop a continuum model for the system which reveals that dissenters act like annealed noise on aligners, with a noise strength that grows with the persistence of the dissenters’ dynamics.

  1. Graphics Processing Unit Enhanced Parallel Document Flocking Clustering

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Xiaohui [ORNL; Potok, Thomas E [ORNL; ST Charles, Jesse Lee [ORNL

    2010-01-01

    Analyzing and clustering documents is a complex problem. One explored method of solving this problem borrows from nature, imitating the flocking behavior of birds. One limitation of this method of document clustering is its complexity O(n2). As the number of documents grows, it becomes increasingly difficult to generate results in a reasonable amount of time. In the last few years, the graphics processing unit (GPU) has received attention for its ability to solve highly-parallel and semi-parallel problems much faster than the traditional sequential processor. In this paper, we have conducted research to exploit this archi- tecture and apply its strengths to the flocking based document clustering problem. Using the CUDA platform from NVIDIA, we developed a doc- ument flocking implementation to be run on the NVIDIA GEFORCE GPU. Performance gains ranged from thirty-six to nearly sixty times improvement of the GPU over the CPU implementation.

  2. Effect of the Feed Additive Clinoptilolite (ZeoFeed on Nutrient Metabolism and Production Performance of Laying Hens

    Directory of Open Access Journals (Sweden)

    Miroslav Macháček

    2010-01-01

    Full Text Available The aim of this study was to assess the effects of two levels of clinoptilolite administered in feed (2% and 4% on some selected performance indicators, metabolic utilization of basic nutrients and the health status of laying hens. The selected 24 Bovans Goldline hybrid laying hens were divided into three equal groups, two experimental groups (E1 and E2 and one control group (C. The laying hens were housed individually in cages with an automatic supply of drinking water, manual feeding, in a setting with controlled light and temperature regimens. Hens from individual groups were all fed a complete feed mix of the same composition and the only difference was in clinoptilolite supplementation: feed mixes for E1 and E2 groups contained 2% and 4% of clinoptilolite (commercial additive ZeoFeed respectively, replacing the same amounts of wheat. The hens received feed mixes and drinking water ad libitum. During this 28-day experiment, feed consumption and the number and weight of eggs laid were monitored individually for each hen. At the end of the experiment, the balance test using the indicator method (Cr2O3 was performed in all eight hens in each of the groups. The results of balance tests were then used to calculate the metabolic utilization of selected nutrients (nitrogen, fat, ash, nitrogen-free extracts, starch, gross energy, Ca, P. After the balance tests, blood samples for haematological and biochemical examinations were collected via puncture of the vena basilica. The addition of 2% clinoptilolite to feed mix resulted in a highly significant (P ⪬ 0.01 increase in mean egg weight to 64.69 g, but the addition of 4% clinoptilolite in group E2 resulted in a highly significant (P ⪬ 0.01 decrease in mean egg weight to 62.20 g compared to the control (63.73 g. Moreover, daily feed mix consumption in group E1 decreased to 114 g per one laying hen/day compared to the controls (118 g per one laying hen/day. In group E2 (4% clinoptilolite, daily

  3. Welfare of organic laying hens kept at different indoor stocking densities in a multi-tier aviary system. II: live weight, health measures and perching.

    Science.gov (United States)

    Steenfeldt, S; Nielsen, B L

    2015-09-01

    Multi-tier aviary systems, where conveyor belts below the tiers remove the manure at regular intervals, are becoming more common in organic egg production. The area on the tiers can be included in the net area available to the hens (also referred to as usable area) when calculating maximum indoor stocking densities in organic systems within the EU. In this article, results on live weight, health measures and perching are reported for organic laying hens housed in a multi-tier system with permanent access to a veranda and kept at stocking densities (D) of 6, 9 and 12 hens/m2 available floor area, with concomitant increases in the number of hens per trough, drinker, perch and nest space. In a fourth treatment, access to the top tier was blocked reducing vertical, trough, and perch access at the lowest stocking density (D6x). In all other aspects than stocking density, the experiment followed the EU regulations on the keeping of organic laying hens. Hen live weight, mortality and foot health were not affected by the stocking densities used in the present study. Other variables (plumage condition, presence of breast redness and blisters, pecked tail feathers, and perch use) were indirectly affected by the increase in stocking density through the simultaneous reduction in access to other resources, mainly perches and troughs. The welfare of the hens was mostly affected by these associated constraints, despite all of them being within the allowed minimum requirements for organic production in the EU. Although the welfare consequences reported here were assessed to be moderate to minor, it is important to take into account concurrent constraints on access to other resources when higher stocking densities are used in organic production.

  4. Flocking with minimal cooperativity: the panic model.

    Science.gov (United States)

    Pilkiewicz, Kevin R; Eaves, Joel D

    2014-01-01

    We present a two-dimensional lattice model of self-propelled spins that can change direction only upon collision with another spin. We show that even with ballistic motion and minimal cooperativity, these spins display robust flocking behavior at nearly all densities, forming long bands of stripes. The structural transition in this system is not a thermodynamic phase transition, but it can still be characterized by an order parameter, and we demonstrate that if this parameter is studied as a dynamical variable rather than a steady-state observable, we can extract a detailed picture of how the flocking mechanism varies with density.

  5. The impact of biosecurity and partial depopulation on Campylobacter prevalence in Irish broiler flocks with differing levels of hygiene and economic performance

    Directory of Open Access Journals (Sweden)

    Shaun Smith

    2016-05-01

    Full Text Available Background: Campylobacter jejuni is the leading bacterial food-borne pathogen within the European Union (EU, and poultry meat is the primary route for transmission to humans. Material and methods: This study examined the impact of partial depopulation (thinning, season, and farm performance (economic, hygiene, and biosecurity on Campylobacter prevalence in Irish broilers over a 13-month period. Ten caecal samples were taken per flock, for a total of 211 flocks from 23 farms during the duration of the study. Campylobacter was isolated and enumerated according to modified published ISO methods for veterinary samples. Biosecurity was evaluated through a questionnaire based on risk factors for Campylobacter identified in previous studies. Hygiene compliance was assessed from audit records taken over the course of 1 year. All information relating to biosecurity and hygiene was obtained directly from the processing company. This was done to ensure farmers were unaware they were being monitored for Campylobacter prevalence and prevent changes to their behaviour. Results and discussion: Farms with high performance were found to have significantly lower Campylobacter prevalence at first depopulation compared with low-performance farms across all seasons (P≤0.01. Peak Campylobacter levels were observed during the summer season at first thin in both the high- and low-performance groups. Campylobacter prevalence was found to increase to ≥85% in both high- and low-performance farms across all seasons at final depopulation, suggesting that Campylobacter was introduced during the first depopulation. On low-performance farms, four biosecurity interventions were found to significantly reduce the odds of a flock being Campylobacter positive (physical step-over barrier OR=0.17, house-specific footwear OR=0.13, absence of water body within 0.5 km OR=0.13, two or more broiler houses on a farm OR=0.16, compared with farms without these interventions. For high

  6. The impact of biosecurity and partial depopulation on Campylobacter prevalence in Irish broiler flocks with differing levels of hygiene and economic performance.

    Science.gov (United States)

    Smith, Shaun; Messam, Locksley L McV; Meade, Joseph; Gibbons, James; McGill, Kevina; Bolton, Declan; Whyte, Paul

    2016-01-01

    Campylobacter jejuni is the leading bacterial food-borne pathogen within the European Union (EU), and poultry meat is the primary route for transmission to humans. This study examined the impact of partial depopulation (thinning), season, and farm performance (economic, hygiene, and biosecurity) on Campylobacter prevalence in Irish broilers over a 13-month period. Ten caecal samples were taken per flock, for a total of 211 flocks from 23 farms during the duration of the study. Campylobacter was isolated and enumerated according to modified published ISO methods for veterinary samples. Biosecurity was evaluated through a questionnaire based on risk factors for Campylobacter identified in previous studies. Hygiene compliance was assessed from audit records taken over the course of 1 year. All information relating to biosecurity and hygiene was obtained directly from the processing company. This was done to ensure farmers were unaware they were being monitored for Campylobacter prevalence and prevent changes to their behaviour. Farms with high performance were found to have significantly lower Campylobacter prevalence at first depopulation compared with low-performance farms across all seasons (P≤0.01). Peak Campylobacter levels were observed during the summer season at first thin in both the high- and low-performance groups. Campylobacter prevalence was found to increase to ≥85% in both high- and low-performance farms across all seasons at final depopulation, suggesting that Campylobacter was introduced during the first depopulation. On low-performance farms, four biosecurity interventions were found to significantly reduce the odds of a flock being Campylobacter positive (physical step-over barrier OR=0.17, house-specific footwear OR=0.13, absence of water body within 0.5 km OR=0.13, two or more broiler houses on a farm OR=0.16), compared with farms without these interventions. For high-performance farms, no single biosecurity intervention was identified as

  7. Risk factors associated with Salmonella enterica serovar typhimurium infection in Danish broiler flocks

    DEFF Research Database (Denmark)

    Skov, M. N.; Angen, Øystein; Chriel, M.

    1999-01-01

    A retrospective longitudinal study was conducted to identify risk factors associated with Salmonella enterica serovar typhimurium (S. typhimurium) infection in Danish broiler flocks. The data included all broiler flocks slaughtered in 1995, and the epidemiological unit was the individual broiler...... flock. The S. typhimurium status was determined by microbiological examination of 60 fresh fecal samples. This procedure should detect an infected flock with a probability above 95%, if the prevalence is above 5%, and given that the sensitivity of the test is 100%. Nineteen variables were selected...... for analysis. Five factors and an interaction term were found significant by multivariate logistic regression analysis. An increased risk for S, typhimurium infection was associated with two parent flocks, one confirmed infected and one suspected of being infected with S. typhimurium, with two...

  8. Nitrogen emissions from broilers measured by mass balance over eighteen consecutive flocks.

    Science.gov (United States)

    Coufal, C D; Chavez, C; Niemeyer, P R; Carey, J B

    2006-03-01

    Emission of nitrogen in the form of ammonia from poultry rearing facilities has been an important topic for the poultry industry because of concerns regarding the effects of ammonia on the environment. Sound scientific data is needed to accurately estimate air emissions from poultry operations. Many factors, such as season of the year, ambient temperature and humidity, bird health, and management practices can influence ammonia volatilization from broiler rearing facilities. Precise results are often difficult to attain from commercial facilities, particularly over long periods of time. Therefore, an experiment was conducted to determine nitrogen loss from broilers in a research facility under conditions simulating commercial production for 18 consecutive flocks. Broilers were reared to 40 to 42 d of age and fed diets obtained from a commercial broiler integrator. New rice hulls were used for litter for the first flock, and the same litter was recycled for all subsequent flocks with caked litter removed between flocks. All birds, feeds, and litter materials entering and leaving the facility were quantified, sampled, and analyzed for total nitrogen content. Nitrogen loss was calculated by the mass balance method in which loss was equal to the difference between the nitrogen inputs and the nitrogen outputs. Nitrogen partitioning as a percentage of inputs averaged 15.29, 6.84, 55.52, 1.27, and 21.08% for litter, caked litter, broiler carcasses, mortalities, and nitrogen loss, respectively, over all eighteen flocks. During the production of 18 flocks of broilers on the same recycled litter, the average nitrogen emission rate was calculated to range from 4.13 to 19.74 g of N/ kg of marketed broiler (grams of nitrogen per kilogram) and averaged 11.07 g of N/kg. Nitrogen loss was significantly (P broiler grow-out facilities varies significantly on a flock-to-flock basis.

  9. Leadership of Winter Mixed-Species Flocks by Tufted Titmice (Baeolophus bicolor: Are Titmice Passive Nuclear Species?

    Directory of Open Access Journals (Sweden)

    Thomas A. Contreras

    2011-01-01

    Full Text Available The tufted titmouse (Baeolophus bicolor, TUTI is a nuclear species in winter foraging flocks whose antipredator calls are used to manage predation risk by diverse heterospecifics. We hypothesized that satellite species in mixed flocks follow TUTI (not vice versa, thereby defining the role of TUTI as a “passive” nuclear species. We followed 20 winter mixed-species flocks in North-Central Florida and assessed angular-angular correlations between overall flock, TUTI, and satellite species movement directions. We observed significant correlations between overall flock movement directions and those of TUTI, confirming our central prediction. Within flocks, however, fine-scale movement directions of satellite species were often more highly correlated with those of other satellites than with TUTI movements. We conclude that TUTI are passive nuclear species whose movements define flock paths, but within flocks, TUTI movements may have less influence on satellite movements than do other factors.

  10. Differences between spent hens of different genotype in performance, meat yield and suitability of the meat for sausage production.

    Science.gov (United States)

    Loetscher, Y; Albiker, D; Stephan, R; Kreuzer, M; Messikommer, R E

    2015-02-01

    The valorization of spent hens via the food chain has some major limitations, which include low meat yield and tough meat. The latter issue can be overcome by producing convenience foods; the first may be alleviated by employing a genotype with higher meatiness. To quantitatively compare two common layer genotypes in production performance, meat yield and sausage quality, 2200 57 weeks old Institut de Sélection Animale (ISA) Warren and Dekalb White hens each were investigated during the last 60 days of egg laying. The hens were housed in an aviary system in 2×10 compartments (10 compartments/each genotype). Measurements included feed intake, laying performance, egg weight and feed conversion ratio as measured per compartment. BW was determined twice on 10 animals per compartment. Finally, two sub-groups of five hens per compartment were slaughtered, meat yield was recorded and bratwurst-type sausages were produced (n=20 per genotype). Fat proportion, cooking loss, connective tissue properties and Kramer shear energy were measured. After 1, 4, 7 and 10 months of frozen storage, oxidative stability (thiobarbituric acid reactive substances (TBARS)) and microbiological status were determined as shelf-life related criteria. ANOVA was performed considering genotype as the main effect. The ISA Warren hens were inferior in laying performance (-11%) and feed conversion ratio (+10%) compared with Dekalb White, but had the same feed intake. The ISA Warren had higher BW and carcass weight than the Dekalb White. Carcass yield was higher by 5.9%. There were 80 g (23%) more meat available for sausage production from ISA Warren compared with Dekalb White. Sausages prepared from meat of ISA Warren hens contained less fat than those from Dekalb White, but showed the same cooking loss. Although the collagen proportion of the sausages produced from ISA Warren was lower than from Dekalb White, collagen solubility was lower and shear energy was higher. During the 10 months of frozen

  11. Prevalence and antimicrobial resistance among Escherichia coli and Salmonella in Ontario smallholder chicken flocks.

    Science.gov (United States)

    Lebert, L; Martz, S-L; Janecko, N; Deckert, A E; Agunos, A; Reid, A; Rubin, J E; Reid-Smith, R J; McEwen, S A

    2018-02-01

    Surveillance is an important component of an overall strategy to address antimicrobial resistant bacteria in food animals and the food chain. The poultry market has many points of entry into the Canadian food chain, and some production practices are underrepresented in terms of surveillance. For example, pathogen carriage and antimicrobial resistance surveillance data are limited in smallholder chicken flocks raised for slaughter at provincially inspected abattoirs. In Canada, antimicrobial resistance in Escherichia coli and Salmonella isolated from commercial broiler chicken flocks, slaughtered at federally inspected abattoirs, is monitored by the Canadian Integrated Program for Antimicrobial Resistance Surveillance (CIPARS). The objective of this study was to establish baseline information of antimicrobial resistance presence in E. coli and Salmonella isolated from smallholder flocks in Ontario, utilizing CIPARS collection and isolation methodologies, and to compare findings with CIPARS federally inspected abattoir data from Ontario, Canada. Five chickens per flock were sampled from 205 smallholder flocks. Of 1,025 samples, the E. coli prevalence was 99% (1,022/1,025), and 47% (483/1,022) of positive E. coli isolates were resistant to one or more of the 14 antimicrobials. Furthermore, as compared to results reported for the CIPARS commercial flocks, E. coli isolates from smallholder flocks had significantly lower resistance prevalence to six of 14 individual antimicrobials. Recovery of E. coli did not differ between federally inspected and provincially inspected flocks. Salmonella prevalence at the bird level in smallholder flocks was 0.3% (3/1,025), significantly lower (p ≪ 0.0001, 95% CI 0.080%-0.86%) than federally inspected commercial flocks. The overall differences found between the commercial and smallholder flocks may be explained by differences in poultry husbandry practices and hatchery sources. © 2017 Her Majesty the Queen in Right of Canada

  12. Decision-making in pigeon flocks: a democratic view of leadership.

    Science.gov (United States)

    Jorge, Paulo E; Marques, Paulo A M

    2012-07-15

    When travelling in groups, animals frequently have to make decisions on the direction of travel. These decisions can be based on consensus, when all individuals take part in the decision (i.e. democratic decision; social information), or leadership, when one member or a minority of members make the decision (i.e. despotic decision; personal information). Here we investigated whether decision-making on the navigation of small flocks is based on democratic or despotic decisions. Using individual and flock releases as the experimental approach, we compared the homing performances of homing pigeons that fly singly and in groups of three. Our findings show that although small groups were either governed (i.e. when individuals in the flock had age differences) or not (i.e. when individuals in the flock had the same age) by leaders, with concern to decision-making they were all ruled by democratic decisions. Moreover, the individual homing performances were not associated with leadership. Because true leaders did not assume right away the front position in the flock, we suggest that as in human groups, starting from a central position is more effective as it allows leaders to not only transmit their own information but also to average the tendencies of the other group members. Together, the results highlight the importance of democratic decisions in group decision-making.

  13. Time-asymptotic interactions of two ensembles of Cucker-Smale flocking particles

    Science.gov (United States)

    Ha, Seung-Yeal; Ko, Dongnam; Zhang, Xiongtao; Zhang, Yinglong

    2017-07-01

    We study the time-asymptotic interactions of two ensembles of Cucker-Smale flocking particles. For this, we use a coupled hydrodynamic Cucker-Smale system and discuss two frameworks, leading to mono-cluster and bi-cluster flockings asymptotically depending on initial configurations, coupling strengths, and the far-field decay property of communication weights. Under the proposed two frameworks, we show that mono-cluster and bi-cluster flockings emerge asymptotically exponentially fast and algebraically slow, respectively. Our asymptotic analysis uses the Lyapunov functional approach and a Lagrangian formulation of the coupled system.

  14. The epizootiology of Eimeria infections in commercial broiler chickens where anticoccidial drug programs were employed in six successive flocks to control coccidiosis.

    Science.gov (United States)

    Chapman, H D; Barta, J R; Hafeez, M A; Matsler, P; Rathinam, T; Raccoursier, M

    2016-08-01

    The course of natural Eimeria infections in 6 successive broiler flocks at a commercial farm comprising 4 houses, where different anticoccidial drug programs were employed, was studied by counting the number of oocysts in the litter at weekly intervals. The course of infection in all flocks followed a bell shaped curve in which oocyst numbers, initially low, increased to a peak ranging from 36 × 10(3) to 74 × 10(3) oocysts/g (OPG) of litter around 3 to 4 wk of age. Numbers subsequently declined to 3 × 10(3) to 15 × 10(3) OPG. Oocysts could be detected between flocks when birds were not present. Species of Eimeria identified included E. acervulina, E. maxima, and E. tenella Despite the presence of large numbers of oocysts in the litter, coccidial lesions were not observed in the intestines of the birds. The performance of broilers at the study site was comparable to that of other farms in the area where birds from the same settlement were reared to a similar age using the same drug programs. The results indicate the ubiquitous nature of Eimeria spp. infections in commercial broilers despite prophylactic medication. © 2016 Poultry Science Association Inc.

  15. Emergent behaviour of a generalized Viscek-type flocking model

    International Nuclear Information System (INIS)

    Ha, Seung-Yeal; Jeong, Eunhee; Kang, Moon-Jin

    2010-01-01

    We present a planar agent-based flocking model with a distance-dependent communication weight. We derive a sufficient condition for the asymptotic flocking in terms of the initial spatial and heading-angle diameters and a communication weight. For this, we employ differential inequalities for the spatial and phase diameters together with the Lyapunov functional approach. When the diameter of the agent's initial heading-angles is sufficiently small, we show that the diameter of the heading-angles converges to the average value of the initial heading-angles exponentially fast. As an application of flocking estimates, we also show that the Kuramoto model with a connected communication topology on the regular lattice Z d for identical oscillators exhibits a complete-phase-frequency synchronization, when coupled oscillators are initially distributed on the half circle

  16. Effects of Furnished Cage Type on Behavior and Welfare of Laying Hens

    Directory of Open Access Journals (Sweden)

    Xiang Li

    2016-06-01

    Full Text Available This study was conducted to compare the effects of layout of furniture (a perch, nest, and sandbox in cages on behavior and welfare of hens. Two hundred and sixteen Hyline Brown laying hens were divided into five groups (treatments with four replicates per group: small furnished cages (SFC, medium furnished cages type I (MFC-I, medium furnished cages type II (MFC-II, and medium furnished cages type III (MFC-III and conventional cages (CC. The experiment started at 18 week of age and finished at 52 week of age. Hens’ behaviors were filmed during the following periods: 8:00 to 10:00; 13:00 to 14:00; 16:00 to 17:00 on three separate days and two hens from each cage were measured for welfare parameters at 50 wk of age. The results showed that feeding and laying of all hens showed no effect by cage type (p>0.05, and the hens in the furnished cages had significantly lower standing and higher walking than CC hens (p0.05. The hens in MFC-I, −II, and −III showed a significant higher socializing behavior than SFC and CC (p<0.05. The lowest perching was for the hens in SFC and the highest perching found for the hens in MFC-III. Overall, the hens in CC showed poorer welfare conditions than the furnished cages, in which the feather condition score, gait score and tonic immobility duration of the hens in CC was significantly higher than SFC, MFC-I, MFC-II, and MFC-III (p<0.05. In conclusion, the furnished cage design affected both behavior and welfare states of hens. Overall, MFC-III cage design was better than SFC, MFC-I, and MFC-II cage designs.

  17. Hydrodynamic Equations for Flocking Models without Velocity Alignment

    Science.gov (United States)

    Peruani, Fernando

    2017-10-01

    The spontaneous emergence of collective motion patterns is usually associated with the presence of a velocity alignment mechanism that mediates the interactions among the moving individuals. Despite of this widespread view, it has been shown recently that several flocking behaviors can emerge in the absence of velocity alignment and as a result of short-range, position-based, attractive forces that act inside a vision cone. Here, we derive the corresponding hydrodynamic equations of a microscopic position-based flocking model, reviewing and extending previous reported results. In particular, we show that three distinct macroscopic collective behaviors can be observed: i) the coarsening of aggregates with no orientational order, ii) the emergence of static, elongated nematic bands, and iii) the formation of moving, locally polar structures, which we call worms. The derived hydrodynamic equations indicate that active particles interacting via position-based interactions belong to a distinct class of active systems fundamentally different from other active systems, including velocity-alignment-based flocking systems.

  18. Dietary menhaden oil contributes to hepatic lipidosis in laying hens.

    Science.gov (United States)

    Van Elswyk, M E; Hargis, B M; Williams, J D; Hargis, P S

    1994-05-01

    Clinical and epidemiological investigations have indicated that there may be substantial human cardiovascular benefits associated with increased consumption of n-3 fatty acids commonly found in fish oils. Recent studies have indicated that egg yolk n-3 fatty acid content is significantly increased when hens are fed diets enriched with selected fish oils such as menhaden oil (MO). In the present study, reproductively active females but not males exhibited increased hepatic lipidosis following 6 mo of feeding 3% MO. Hens fed 3% animal-vegetable oil (AV) did not exhibit hepatic lipid accumulation. Serum triglyceride and cholesterol concentrations were reduced (P < or = .05) in hens fed MO. Subsequently, yolk and total egg weights of hens fed MO were decreased as compared with those of hens fed AV. A significant interaction of dietary MO and exogenous 17 beta-estradiol was noted among chick liver and gallbladder weights. These data suggest that dietary MO and estradiol may interact in a manner that enhances the lipogenic activity of the liver, thereby inducing hepatic lipidosis in laying hens.

  19. Obesity-associated cardiac pathogenesis in broiler breeder hens: Pathological adaption of cardiac hypertrophy.

    Science.gov (United States)

    Chen, C Y; Lin, H Y; Chen, Y W; Ko, Y J; Liu, Y J; Chen, Y H; Walzem, R L; Chen, S E

    2017-07-01

    Broiler hens consuming feed to appetite (ad libitum; AL) show increased mortality. Feed restriction (R) typically improves reproductive performance and livability of hens. Rapidly growing broilers can exhibit increased mortality due to cardiac insufficiency but it is unknown whether the increased mortality of non-R broiler hens is also due to cardiac compromise. To assess cardiac growth and physiology in fully mature birds, 45-week-old hens were either continued on R rations or assigned to AL feeding for 7 or 21 days. AL hens exhibited increased bodyweight, adiposity, absolute and relative heart weight, ventricular hypertrophy, and cardiac protein/DNA ratio by d 21 (P hens (P Hens allowed AL feeding for 70 d exhibited a higher incidence of mortality (40% vs. 10%) in association with ascites, pericardial effusion, and ventricle dilation. A higher incidence of irregular ECG patterns and rhythmicity consistent with persistently elevated systolic blood pressure and ventricle fibrosis were observed in AL hens (P feeding in broiler hens results in maladaptive cardiac hypertrophy that progresses to overt pathogenesis in contractility and thereby increases mortality. Feed restriction provides clear physiological benefit to heart function of adult broiler hens. © 2017 Poultry Science Association Inc.

  20. Foraging intention affects whether willow tits call to attract members of mixed-species flocks.

    Science.gov (United States)

    Suzuki, Toshitaka N; Kutsukake, Nobuyuki

    2017-06-01

    Understanding how individual behaviour influences the spatial and temporal distribution of other species is necessary to resolve the complex structure of species assemblages. Mixed-species bird flocks provide an ideal opportunity to investigate this issue, because members of the flocks are involved in a variety of behavioural interactions between species. Willow tits ( Poecile montanus ) often produce loud calls when visiting a new foraging patch to recruit other members of mixed-species flocks. The costs and benefits of flocking would differ with individual foraging behaviours (i.e. immediate consumption or caching); thus, willow tits may adjust the production of loud calls according to their foraging intention. In this study, we investigated the link between foraging decisions and calling behaviour in willow tits and tested its influence on the temporal cohesion with members of mixed-species flocks. Observations at experimental foraging patches showed that willow tits produced more calls when they consumed food items compared with when they cached them. Playback experiments revealed that these calls attracted flock members and helped to maintain their presence at foraging patches. Thus, willow tits adjusted calling behaviour according to their foraging intention, thereby coordinating the associations with members of mixed-species flocks. Our findings demonstrate the influence of individual decision-making on temporal cohesion with other species and highlight the importance of interspecific communication in mixed-species flocking dynamics.

  1. Influence of Natural Zeolite on Performance of Laying Hens and Egg Quality

    OpenAIRE

    ÖZTÜRK, Ergin; ERENER, Güray; SARICA, Musa

    2014-01-01

    This experiment was conducted to study the effects of natural zeolite on the performance of laying hens. One hundred and eighty 37-week-old Babcock B-300 hens were fed with a diet containing 0, 20, 40, 60 and 80 g clinoptilolite/kg in an experiment consisting of 36 hens per treatment during a 4x28 days experimental period. All feeding programs were isocaloric and isonitrogenous. Hens were put at random into 5 treatment groups (12 replicates and 36 hens per treatment). No significant dietar...

  2. Does mixed-species flocking influence how birds respond to a gradient of land-use intensity?

    Science.gov (United States)

    Mammides, Christos; Chen, Jin; Goodale, Uromi Manage; Kotagama, Sarath Wimalabandara; Sidhu, Swati; Goodale, Eben

    2015-07-22

    Conservation biology is increasingly concerned with preserving interactions among species such as mutualisms in landscapes facing anthropogenic change. We investigated how one kind of mutualism, mixed-species bird flocks, influences the way in which birds respond to different habitat types of varying land-use intensity. We use data from a well-replicated, large-scale study in Sri Lanka and the Western Ghats of India, in which flocks were observed inside forest reserves, in 'buffer zones' of degraded forest or timber plantations, and in areas of intensive agriculture. We find flocks affected the responses of birds in three ways: (i) species with high propensity to flock were more sensitive to land use; (ii) different flock types, dominated by different flock leaders, varied in their sensitivity to land use and because following species have distinct preferences for leaders, this can have a cascading effect on followers' habitat selection; and (iii) those forest-interior species that remain outside of forests were found more inside flocks than would be expected by chance, as they may use flocks more in suboptimal habitat. We conclude that designing policies to protect flocks and their leading species may be an effective way to conserve multiple bird species in mixed forest and agricultural landscapes. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  3. Response of shaver brown hens to feeds of different sources in the ...

    African Journals Online (AJOL)

    A twelve-week study was conducted to determine the effect of feed type on performance of Shaver brown hens in the humid tropical environment. One hundred and twenty (120) Shaverbrown hens of 28 weeks of age were used for the study.The hens were divided into five groups of 24 hens each and each group was ...

  4. Depopulation of Caged Layer Hens with a Compressed Air Foam System

    Science.gov (United States)

    Gurung, Shailesh; Hoffman, John; Stringfellow, Kendre; Abi-Ghanem, Daad; Zhao, Dan; Caldwell, David; Lee, Jason; Styles, Darrel; Berghman, Luc; Byrd, James; Farnell, Yuhua; Archer, Gregory

    2018-01-01

    Simple Summary Reportable diseases, such as avian influenza, spread rapidly among poultry, resulting in the death of a large number of birds. Once such a disease has been diagnosed at a farm, infected and susceptible birds are rapidly killed to prevent the spread of the disease. The methods to eliminate infected caged laying hens are limited. An experiment was conducted to study the effectiveness of foam made from compressed air, water, and soap to kill laying hens in cages. The study found that stress levels of the hens killed using compressed air foam in cages to be similar to the hens killed by carbon dioxide or the negative control. Hens exposed to carbon dioxide died earlier as compared to the foam methods. The authors conclude that application of compressed air foam in cages is an alternative to methods such as gas inhalation and ventilation shutdown to rapidly and humanely kill laying hens during epidemics. Abstract During the 2014–2015 US highly pathogenic avian influenza (HPAI) outbreak, 50.4 million commercial layers and turkeys were affected, resulting in economic losses of $3.3 billion. Rapid depopulation of infected poultry is vital to contain and eradicate reportable diseases like HPAI. The hypothesis of the experiment was that a compressed air foam (CAF) system may be used as an alternative to carbon dioxide (CO2) inhalation for depopulating caged layer hens. The objective of this study was to evaluate corticosterone (CORT) and time to cessation of movement (COM) of hens subjected to CAF, CO2 inhalation, and negative control (NEG) treatments. In Experiment 1, two independent trials were conducted using young and spent hens. Experiment 1 consisted of five treatments: NEG, CO2 added to a chamber, a CO2 pre-charged chamber, CAF in cages, and CAF in a chamber. In Experiment 2, only spent hens were randomly assigned to three treatments: CAF in cages, CO2 added to a chamber, and aspirated foam. Serum CORT levels of young hens were not significantly

  5. Effect of in-house chicken litter composting on ammonia and nitrous oxide emissions and pathogen reduction

    Science.gov (United States)

    Inhouse composting is a management practice to reduce pathogen in poultry litter. In between flocks, growers windrow the litter inside the broiler houses. This results in high temperatures that can reduce some pathogens in the litter. However, this practice is likely to increase emissions of NH3 and...

  6. Modelling energy utilisation in broiler breeder hens.

    Science.gov (United States)

    Rabello, C B V; Sakomura, N K; Longo, F A; Couto, H P; Pacheco, C R; Fernandes, J B K

    2006-10-01

    1. The objective of this study was to determine a metabolisable energy (ME) requirement model for broiler breeder hens. The influence of temperature on ME requirements for maintenance was determined in experiments conducted in three environmental rooms with temperatures kept constant at 13, 21 and 30 degrees C using a comparative slaughter technique. The energy requirements for weight gain were determined based upon body energy content and efficiency of energy utilisation for weight gain. The energy requirements for egg production were determined on the basis of egg energy content and efficiency of energy deposition in the eggs. 2. The following model was developed using these results: ME = kgW0.75(806.53-26.45T + 0.50T2) + 31.90G + 10.04EM, where kgW0.75 is body weight (kg) raised to the power 0.75, T is temperature ( degrees C), G is weight gain (g) and EM is egg mass (g). 3. A feeding trial was conducted using 400 Hubbard Hi-Yield broiler breeder hens and 40 Peterson males from 31 to 46 weeks of age in order to compare use of the model with a recommended feeding programme for this strain of bird. The application of the model in breeder hens provided good productive and reproductive performance and better results in feed and energy conversion than in hens fed according to strain recommendation. In conclusion, the model evaluated predicted an ME intake which matched breeder hens' requirements.

  7. Flocking of the Motsch-Tadmor Model with a Cut-Off Interaction Function

    Science.gov (United States)

    Jin, Chunyin

    2018-04-01

    In this paper, we study the flocking behavior of the Motsch-Tadmor model with a cut-off interaction function. Our analysis shows that connectedness is important for flocking of this kind of model. Fortunately, we get a sufficient condition imposed only on the model parameters and initial data to guarantee the connectedness of the neighbor graph associated with the system. Then we present a theoretical analysis for flocking, and show that the system achieves consensus at an exponential rate.

  8. Micro-flock patterns and macro-clusters in chiral active Brownian disks

    Science.gov (United States)

    Levis, Demian; Liebchen, Benno

    2018-02-01

    Chiral active particles (or self-propelled circle swimmers) feature a rich collective behavior, comprising rotating macro-clusters and micro-flock patterns which consist of phase-synchronized rotating clusters with a characteristic self-limited size. These patterns emerge from the competition of alignment interactions and rotations suggesting that they might occur generically in many chiral active matter systems. However, although excluded volume interactions occur naturally among typical circle swimmers, it is not yet clear if macro-clusters and micro-flock patterns survive their presence. The present work shows that both types of pattern do survive but feature strongly enhance fluctuations regarding the size and shape of the individual clusters. Despite these fluctuations, we find that the average micro-flock size still follows the same characteristic scaling law as in the absence of excluded volume interactions, i.e. micro-flock sizes scale linearly with the single-swimmer radius.

  9. Herd immunity to Newcastle disease virus in broiler flocks in Israel.

    Science.gov (United States)

    Wiseman, Anat; Berman, Elyakum M

    2017-08-01

    Due to the ongoing need to protect poultry from virulent Newcastle disease virus, all commercial poultry flocks in Israel are vaccinated according to a defined programme using a combination of live and inactivated vaccines. The vaccination protocol for broilers during the years of the study comprised a live vaccine administered by spray on the day of hatching, inactivated vaccine by subcutaneous injection at 10-12 days of age, and another live vaccine given by aerosol at 17-21 days of age. A cross-sectional study was designed in order to examine the influence of herd immunity on the risk of Newcastle disease outbreak in broiler flocks. The study was based on the extensive field data kept in the Poultry Health Laboratories database. The results of serology tests employing haemagglutination inhibition for Newcastle disease virus were analysed and crossed with the list of flocks that had been diagnosed with ND in the years 2007-2014. At the peak of induced immunization (fifth week of growth), 87.5% of the tested flocks had achieved herd immunity (≥85% of birds in the flock with an HI titre ≥4). Based on a logistic regression model, the odds ratio for ND in flocks without herd immunity was 3.7 (95% CI 1.8-7.3, P-value < 0.001). The higher the percentage of birds with low HI titres the higher the risk of ND outbreak. Under field conditions, herd immunity is an important indicator for the risk of ND outbreak.

  10. Foraging efficiency of a predator flock for randomly moving prey: A simulation study

    Science.gov (United States)

    Lee, Sang-Hee; Kwon, Ohsung

    2016-03-01

    Flocking behavior of animals is highly advantageous for taking food resources. The degree of the advantage is related to the ability of flock members to detect their prey and the mobility of prey individuals. In this study, to explore the relation, we constructed a model to simulate a predator flock and its randomly moving prey. The predator members have the prey detection ability, which was characterized as sensing distance, R, and a sensing angle, θ. The mobility of the prey individuals was characterized as the maximum traveling distance of an iteration time step, L. The relative flock foraging efficiency, ɛ, was defined as ɛ = 1 - (Td/Tup). Tup and Td represent the spent time for the flock to eat all prey individuals and to uptake the last remaining 10% prey, respectively. Simulation results showed that ɛ increased, maximized, and decreased with the increase of R, regardless of L. As the number of prey, N, increased, the tendency of the increasing and decreasing was diluted. The result was briefly discussed in relation to the flock foraging behavior and the development of the model toward applications for real ecosystems.

  11. Hot Electron Nanoscopy and Spectroscopy (HENs)

    KAUST Repository

    Giugni, Andrea; Torre, Bruno; Allione, Marco; Perozziello, Gerardo; Candeloro, Patrizio; Di Fabrizio, Enzo M.

    2017-01-01

    This chapter includes a brief description of different laser coupling methods with guided surface plasmon polariton (SPP) modes at the surface of a cone. It shows some devices, their electromagnetic simulations, and their optical characterization. A theoretical section illustrates the optical and quantum description of the hot charge generation rate as obtained for the SPP propagation along the nanocone in adiabatic compression. The chapter also shows some experimental results concerning the application of the hot electron nanoscopy and spectroscopy (HENs) in the so-called Schottky configuration, highlighting the sensitivity and the nanoscale resolution of the technique. The comparison with Kelvin probe and other electric atomic force microscopy (AFM) techniques points out the intrinsic advantages of the HENs. In the end, some further insights are given about the possibility of exploiting HENs with a pulsed laser at the femtosecond time scale without significant pulse broadening and dispersion.

  12. Hot Electron Nanoscopy and Spectroscopy (HENs)

    KAUST Repository

    Giugni, Andrea

    2017-08-17

    This chapter includes a brief description of different laser coupling methods with guided surface plasmon polariton (SPP) modes at the surface of a cone. It shows some devices, their electromagnetic simulations, and their optical characterization. A theoretical section illustrates the optical and quantum description of the hot charge generation rate as obtained for the SPP propagation along the nanocone in adiabatic compression. The chapter also shows some experimental results concerning the application of the hot electron nanoscopy and spectroscopy (HENs) in the so-called Schottky configuration, highlighting the sensitivity and the nanoscale resolution of the technique. The comparison with Kelvin probe and other electric atomic force microscopy (AFM) techniques points out the intrinsic advantages of the HENs. In the end, some further insights are given about the possibility of exploiting HENs with a pulsed laser at the femtosecond time scale without significant pulse broadening and dispersion.

  13. Footpad dermatitis in Dutch broiler flocks: Prevalence and factors of influence

    NARCIS (Netherlands)

    Jong, de I.C.; Harn, van J.; Gunnink, H.; Hindle, V.A.; Lourens, A.

    2012-01-01

    In some European countries, footpad dermatitis (FPD) is measured as an indicator of broiler welfare. Prevalence and seasonal variation of FPD was determined within broiler flocks (fast-growing breeds) in the Netherlands. Samples were taken from 386 Dutch flocks at 8 slaughterhouses during a period

  14. Exposure to increased environmental complexity during rearing reduces fearfulness and increases use of three-dimensional space in laying hens (Gallus gallus domesticus

    Directory of Open Access Journals (Sweden)

    Margrethe eBrantsæter

    2016-02-01

    Full Text Available The complexity of the rearing environment is important for behavioral development and fearfulness. The aim of this study was to test the hypothesis that laying hens reared in a complex aviary system with exposure to mild intermittent stressors, would be less fearful, less sensitive to stress, and would use elevated areas of the pen more often as adults than hens reared in a barren cage environment. Laying hens (N = 160 were housed in the same rearing house; half of the birds (n = 80 in an aviary and the other half (n = 80 in cages. At 16 weeks of age, the birds were transported to the experimental facilities. Their behavior was recorded at 19 and 23 weeks of age and analyzed by ANOVA on individual scores for a fearfulness-related principal component generated using principal component analysis (PCA. The results indicate that aviary-reared birds had lower levels of fearfulness, compared with cage-reared birds both at 19 weeks and at 23 weeks of age. When comparing the response induced by initial exposure to a novel object at 19 and 23 weeks of age, more aviary-reared birds tended to fly up at 19 weeks compared to the cage-reared birds, indicating a tendency towards a more active behavioral response in the aviary- than in cage-reared birds. There was no difference between treatments in the flight response at 23 weeks. The groups did not differ in defecation frequency or the concentration of fecal corticosterone metabolites at either age. At 19 weeks, observation of the spatial distribution in the home pens indicated that more aviary-reared birds spent time on the low perch, the elevated platform and upper perch compared to the cage-reared birds. However, at 23 weeks of age, these differences were no longer detected. The results of this study support the hypothesis that increased environmental complexity during rearing reduces fearfulness of adult laying hens.

  15. 'As I told Henning the other day'

    DEFF Research Database (Denmark)

    Andersen, Nina Møller

    2008-01-01

    En analyse af sætningen 'Som jeg også sagde til Henning forleden dag' ud fra henholdsvis en klassisk argumentationsanalytisk synsvinkel, en sproghandlingsanalytisk synsvinkel og en dialogisk sysnvinkel (BAchtin)......En analyse af sætningen 'Som jeg også sagde til Henning forleden dag' ud fra henholdsvis en klassisk argumentationsanalytisk synsvinkel, en sproghandlingsanalytisk synsvinkel og en dialogisk sysnvinkel (BAchtin)...

  16. Decay of interspecific avian flock networks along a disturbance gradient in Amazonia

    Science.gov (United States)

    Mokross, Karl; Ryder, Thomas B.; Côrtes, Marina Corrêa; Wolfe, Jared D.; Stouffer, Philip C

    2014-01-01

    Our understanding of how anthropogenic habitat change shapes species interactions is in its infancy. This is in large part because analytical approaches such as network theory have only recently been applied to characterize complex community dynamics. Network models are a powerful tool for quantifying how ecological interactions are affected by habitat modification because they provide metrics that quantify community structure and function. Here, we examine how large-scale habitat alteration has affected ecological interactions among mixed-species flocking birds in Amazonian rainforest. These flocks provide a model system for investigating how habitat heterogeneity influences non-trophic interactions and the subsequent social structure of forest-dependent mixed-species bird flocks. We analyse 21 flock interaction networks throughout a mosaic of primary forest, fragments of varying sizes and secondary forest (SF) at the Biological Dynamics of Forest Fragments Project in central Amazonian Brazil. Habitat type had a strong effect on network structure at the levels of both species and flock. Frequency of associations among species, as summarized by weighted degree, declined with increasing levels of forest fragmentation and SF. At the flock level, clustering coefficients and overall attendance positively correlated with mean vegetation height, indicating a strong effect of habitat structure on flock cohesion and stability. Prior research has shown that trophic interactions are often resilient to large-scale changes in habitat structure because species are ecologically redundant. By contrast, our results suggest that behavioural interactions and the structure of non-trophic networks are highly sensitive to environmental change. Thus, a more nuanced, system-by-system approach may be needed when thinking about the resiliency of ecological networks. PMID:24335983

  17. Variability in amino acid digestibility of triticale grain from diverse genotypes as studied in cecectomized laying hens.

    Science.gov (United States)

    Zuber, T; Maurer, H P; Möhring, J; Nautscher, N; Siegert, W; Rosenfelder, P; Rodehutscord, M

    2016-12-01

    Triticale, an anthropogenic hybrid grain, is increasing in importance as a feed grain for laying hens. However, our limited knowledge of its nutritional qualities and their impact on hen performance prevents optimization of its use. The present study investigated the digestibility of amino acids ( AA: ) in triticale grain in laying hens, and additionally examined relationships between AA digestibility and chemical and physical characteristics of the grain. Twenty genotypes of triticale were grown under standardized agronomic and environmental conditions and were characterized according to their physical properties (thousand-seed weight, test weight, falling number, extract viscoelasticity), chemical composition (proximate nutrients, non-starch polysaccharides, AA, minerals, inositol phosphates) and gross energy concentration. Additionally, the in vitro solubility of nitrogen was determined. The animal trial comprised 4 Latin Squares (6 × 6) distributed among 2 subsequent runs. Twelve cecectomized LSL-Classic hens were individually housed in metabolism cages and either fed a basal diet containing 500 g/kg cornstarch or one of 20 triticale diets, each replacing the cornstarch with one triticale genotype, for 8 d. During the last 4 d, feed intake was recorded and excreta were collected quantitatively. Amino acid digestibility of the triticale genotypes was calculated by linear regression. The digestibility of all AA differed significantly between the 20 genotypes, including Lys (digestibility range 68 to 80%), Met (77 to 86%), Thr (68 to 78%) and Trp (74 to 83%). However, AA digestibility only correlated with characteristics of the grain in few cases, without a consistent pattern among AA. Equations to predict AA digestibility based on the grain's physical and chemical characteristics were calculated by multiple linear regression. The explanatory power (adjusted R 2 ;) of these prediction equations was below 0.7 for most AA and thus not sufficiently precise to be

  18. Obesity-associated cardiac pathogenesis in broiler breeder hens: Development of metabolic cardiomyopathy.

    Science.gov (United States)

    Chen, C Y; Huang, Y F; Ko, Y J; Liu, Y J; Chen, Y H; Walzem, R L; Chen, S E

    2017-07-01

    Feed intake is typically restricted (R) in broiler hens to avoid obesity and improve egg production and livability. To determine whether improved heart health contributes to improved livability, fully adult 45-week-old R hens were allowed to consume feed to appetite (ad libitum; AL) up to 10 wk (70 d). Mortality, contractile functions, and morphology at 70 d, and measurements of cardiac hypertrophic remodeling at 7 d and 21 d were made and compared between R and AL hens. Outcomes for cardiac electrophysiology and mortality, reported separately, found increased mortality in AL hens in association with cardiac pathological hypertrophy and contractile dysfunction. The present study aimed to delineate metabolic cardiomyopathies underlying the etiology of obesity-associated cardiac pathology. Metabolic measurements were made in hens continued on R rations or assigned to AL feeding after 7 d and 21 days. AL feeding increased plasma insulin, glucose, and non-esterified fatty acid (NEFA) concentrations by 21 d (P hens was confirmed by cardiac triacylglycerol (TG) and ceramide accumulation consistent with up-regulation of related enzyme gene expressions, and by increased indices of oxidation stress (P hens, cardiac pyruvate dehydrogenase (PDH) activity and glucose transporter (GLUT) gene expressions increased progressively while carnitine palmitoyltransferase-1 (CPT-1) transcript levels in AL hens declined from 7 d to 21 d (P hens was further indicated by increased leukocyte infiltrates, interleukin-1β (IL-1β) and IL-6 production, cellular apoptosis, interstitial fibrosis, and expression of the heart failure marker myosin heavy chain (MHC-β; cardiac muscle beta) (P hens. © 2017 Poultry Science Association Inc.

  19. 9 CFR 147.21 - Flock sanitation.

    Science.gov (United States)

    2010-01-01

    ... allow the litter to be maintained in a dry condition. Frequent stirring of the litter may be necessary... status of both the flock and introduced birds should be evaluated. (h) In rearing broiler or replacement...

  20. Effect of dietary supplementation of Ligustrum lucidum on performance, egg quality and blood biochemical parameters of Hy-Line Brown hens during the late laying period.

    Science.gov (United States)

    Li, X L; He, W L; Yang, M L; Yan, Y M; Xue, Y H; Zhao, S T

    2017-11-01

    The fruit of Ligustrum lucidum (FLL, Nuzhenzi in Chinese) is an important traditional medicine, and have attracted significant research attention because of their various biological activities. However, there are few research reports available on the use of FLL as a feed additive in livestock nutrition, particularly in layers. This study was conducted to determine the effects of supplementation of the diet of laying hens with FLL on laying performance, egg quality and blood metabolites. A total of 360 72-week-old hens were allocated to three dietary treatments (eight replications of 15 hens/treatment group) and were fed either a control diet or a diet supplemented with an inclusion level of 0.25% or 0.50% of FLL powder in the final feed, until 78 weeks of age. Hens were housed in a three-tier cage system. Feed and water were provided ad libitum. Blood samples and eggs were collected at the end of the experiment. The results showed that dietary supplementation with FLL did not affect egg weight, feed conversion ratio, eggshell thickness, albumen height, egg yolk color, eggshell breaking strength or egg shape index. However, FLL supplementation significantly decreased (Phens fed FLL compared with the control group. It can be concluded that FLL, at a supplementation level of 0.25% final feed, can be used as an effective feed additive to improve the performance of laying hens during the late laying period.

  1. Effect of refined functional carbohydrates from enzymatically hydrolyzed yeast on the presence of Salmonella spp. in the ceca of broiler breeder females.

    Science.gov (United States)

    Walker, G K; Jalukar, S; Brake, J

    2017-08-01

    Broiler breeders hatched from Salmo-nella negative grandparents received either zero or 50 g/MT of refined functional carbohydrates (RFC) in their diets from d of placement to end of lay. There were no other treatments used. Pullets and cockerels were reared separately in an enclosed litter-floor house to 21 wk of age when 28 randomly selected pullets from each diet were transferred to individual cages for an additional 14 d before they were killed, and their ceca were excised aseptically and tested for Salmonella spp. The remaining birds were transferred to a two-thirds slat and one-third litter curtain-sided laying house. There were 8 pens of 60 to 65 females and 8 to 18 males, depending upon flock age and housing type, fed each diet, and there was no effort made to isolate pens from typical daily foot traffic between pens. At 51 wk of age, male progeny broiler chicks were hatched and received either zero or 50 g/MT of RFC to complete a 2 × 2 design with 4 replicate pens of 12 males per interaction. All broilers were tested for cecal Salmonella spp. at 34 d of age. Ceca were collected from 30 breeder hens from each treatment at 64 wk of age and tested for Salmonella spp. Of the ceca sampled at 23 wk from the control pullets, 71.4% were found to contain Salmonella spp., while none of the ceca from the RFC pullets tested positive. Of the ceca sampled from the control hens at 64 wk, 40% were found to contain Salmonella spp., while none of the ceca from the RFC hens tested positive. Salmonella spp. was isolated from broilers in one pen of the control broilers that were also progeny of control breeders out of 4 replicates but not from any pens in which the breeders had been fed RFC. These data demonstrated that RFC reduced natural Salmonella spp. colonization of broiler breeder hen and broiler progeny ceca during a complete production cycle. © 2017 Poultry Science Association Inc.

  2. Corrosion resistance of tank material for flock storage in the Fukushima Daiichi Nuclear Power Plant

    International Nuclear Information System (INIS)

    Sano, Yuichi; Anbai, Hiromu; Takeuchi, Masayuki; Ogino, Hideki; Koizumi, Kenji

    2014-01-01

    The installation of the storage tank made of SS400 is under planning in the Fukushima Daiichi nuclear power plant for the flock which was generated in the coagulation process for radioactive contaminated water. The flock contains the seawater and has a possibility to make a crevice and local corrosion on the surface of the tank. Air agitation will be applied in the storage tank to prevent the accumulation of the flock and hydrogen generated by radiolysis, which will increase the diffusion of oxygen and the corrosion of SS400. In addition, the effect of radiation from the flock on the corrosion should be considered. In this study, we investigated the corrosion behavior of SS400 in the flock under the aeration-agitation condition with γ-ray irradiation. Based on the flock storage condition announced by Tokyo Electric Power Company (TEPCO), immersion tests were performed with SS400 coupons under several conditions and corrosion rates were estimated by the weight loss of the coupons. After the immersion tests, the surfaces of the coupons were observed by microscopy for evaluating the local corrosion. To evaluate corrosion mechanism in detail, electrochemical tests were also carried out. In all of these tests, the non-radioactive flock as a surrogate and artificial seawater were used. Corrosion rates of SS400 increased significantly with aeration flow rates in the seawater with/without the flock, but this tendency was weaker in the seawater with the flock, especially under the condition where coupons were buried in the flock. The electrochemical tests indicated the suppression of the cathodic reaction, i.e. dissolved oxygen reduction, in the seawater with the flock. The effect of γ-ray irradiation on the corrosion rates was not remarkable under the assumed dose rate. Microscopic analysis of the immersed coupons showed no severe corrosion including local corrosion occurred. The corrosion rate could be decreased effectively by suppressing the dissolved oxygen reduction

  3. Effects of Furnished Cage Type on Behavior and Welfare of Laying Hens

    Science.gov (United States)

    Li, Xiang; Chen, Donghua; Li, Jianhong; Bao, Jun

    2016-01-01

    This study was conducted to compare the effects of layout of furniture (a perch, nest, and sandbox) in cages on behavior and welfare of hens. Two hundred and sixteen Hyline Brown laying hens were divided into five groups (treatments) with four replicates per group: small furnished cages (SFC), medium furnished cages type I (MFC-I), medium furnished cages type II (MFC-II), and medium furnished cages type III (MFC-III) and conventional cages (CC). The experiment started at 18 week of age and finished at 52 week of age. Hens’ behaviors were filmed during the following periods: 8:00 to 10:00; 13:00 to 14:00; 16:00 to 17:00 on three separate days and two hens from each cage were measured for welfare parameters at 50 wk of age. The results showed that feeding and laying of all hens showed no effect by cage type (p>0.05), and the hens in the furnished cages had significantly lower standing and higher walking than CC hens (phens between the furnished cages (p>0.05). The hens in MFC-I, −II, and −III showed a significant higher socializing behavior than SFC and CC (phens in SFC and the highest perching found for the hens in MFC-III. Overall, the hens in CC showed poorer welfare conditions than the furnished cages, in which the feather condition score, gait score and tonic immobility duration of the hens in CC was significantly higher than SFC, MFC-I, MFC-II, and MFC-III (phens. Overall, MFC-III cage design was better than SFC, MFC-I, and MFC-II cage designs. PMID:26954171

  4. Who Is Spreading Avian Influenza in the Moving Duck Flock Farming Network of Indonesia?

    Directory of Open Access Journals (Sweden)

    Joerg Henning

    Full Text Available Duck populations are considered to be a reservoir of Highly pathogenic avian influenza (HPAI virus H5N1 in some agricultural production systems, as they are able to shed the virus for several days without clinical signs. Countries endemically affected with HPAI in Asia are characterised by production systems where ducks are fed on post-harvest spilled rice. During this scavenging process it is common for ducks to come into contact with other duck flocks or wild birds, thereby providing opportunities for virus spread. Effective risk management for HPAI has been significantly compromised by a limited understanding of management of moving duck flocks in these countries, despite of a small number of recent investigations. Here, for the first time, we described the management of moving duck flocks and the structure of the moving duck flock network in quantitative terms so that factors influencing the risk of HPAIV transmission can be identified. By following moving duck flock farmers over a period of 6 months in Java, Indonesia, we were able to describe the movement of flocks and to characterise the network of various types of actors associated with the production system. We used these data to estimate the basic reproductive number for HPAI virus spread. Our results suggest that focussing HPAI prevention measures on duck flocks alone will not be sufficient. Instead, the role of transporters of moving duck flocks, hatcheries and rice paddy owners, in the spread of the HPAI virus needs to be recognised.

  5. Effect of climate and farm environment on Campylobacter spp. colonisation in Norwegian broiler flocks

    DEFF Research Database (Denmark)

    Jonsson, Malin E.; Chriél, Mariann; Norström, Madelaine

    2012-01-01

    of Campylobacter spp. in Norwegian broiler flocks and factors related to the climate and the farm environment. Data from 18,488 broiler flocks from 623 different farms during 2002–2007 were included in the study. A logistic regression analysis was conducted where Campylobacter spp. status of a broiler flock...... at the time of slaughter was defined as the dependent variable and farm was modelled as a random effect. The following factors were found to increase the probability for a broiler flock to test positive for Campylobacter spp.: daily mean temperature above 6°C during the rearing period, private water supply...

  6. Boundary Information Inflow Enhances Correlation in Flocking

    Science.gov (United States)

    Cavagna, Andrea; Giardina, Irene; Ginelli, Francesco

    2013-04-01

    The most conspicuous trait of collective animal behavior is the emergence of highly ordered structures. Less obvious to the eye, but perhaps more profound a signature of self-organization, is the presence of long-range spatial correlations. Experimental data on starling flocks in 3D show that the exponent ruling the decay of the velocity correlation function, C(r)˜1/rγ, is extremely small, γ≪1. This result can neither be explained by equilibrium field theory nor by off-equilibrium theories and simulations of active systems. Here, by means of numerical simulations and theoretical calculations, we show that a dynamical field applied to the boundary of a set of Heisenberg spins on a 3D lattice gives rise to a vanishing exponent γ, as in starling flocks. The effect of the dynamical field is to create an information inflow from border to bulk that triggers long-range spin-wave modes, thus giving rise to an anomalously long-ranged correlation. The biological origin of this phenomenon can be either exogenous—information produced by environmental perturbations is transferred from boundary to bulk of the flock—or endogenous—the flock keeps itself in a constant state of dynamical excitation that is beneficial to correlation and collective response.

  7. Prevalence of Salmonella spp. in environmental samples from table egg barns in Alberta.

    Science.gov (United States)

    St Amand, Joan A; Cassis, Rashed; King, Robin K; Annett Christianson, Colleen B

    2017-12-01

    Some Salmonella spp. are zoonotic, a frequent cause of foodborne illness in Canada, and known to infect humans through contaminated poultry and poultry products. Certain serotypes of Salmonella spp. have been demonstrated to be vertically transmitted from hen to egg. The incidence of Salmonella spp. isolation in the flock has been correlated to its isolation from the environment. Twenty-one producers were enrolled in this study to examine the occurrence of Salmonella spp. in 48 table egg layer flocks housed in 35 barns in Alberta. The purpose of this study was to: (i) identify Salmonella serotypes isolated from the environment of table egg layer facilities in Alberta and (ii) record the prevalence of Salmonella spp. across eight defined environmental sampling points. Salmonella spp. were isolated from the environment of 20/35 barns representing 29/48 flocks. The most common serotypes isolated were S. Heidelberg, S. Kentucky and S. Mbandaka. The order of most to least contaminated sample location was manure belts (54.1%), feeders (47.9%), feed motors (45.8%), egg belts and walls (41.7%), fans (35.0%), cage bottoms (31.3%) and lobbies (27.1%). Salmonella spp. were isolated from 7/7 barns post cleaning and disinfection, demonstrating the persistence of this organism in the environment and the need for effective eradication protocols.

  8. Studies on the structure and problems of family poultry production in Tanzania

    International Nuclear Information System (INIS)

    Msami, H.M.

    2002-01-01

    In order to identify the major disease conditions and factors limiting family chicken production in Coast and Dar-es-Salaam regions of Tanzania a survey was undertaken in six villages in two zones involving a total of 43 households. Field data were collected through identified farmer interviews in the wet and dry seasons of 1999/2000. During farm visits, the birds were clinically examined, sick and dead ones autopsied. Blood smears, serum and faecal samples were collected for laboratory examination. There was significant variation in the flock size and structure in the interviewed households. The 43 households kept 1099 chickens with an average of 25.5 per household in the wet season while in the dry season the numbers were 1352 and an average of 31.4. The ratio of chicks:growers: aduIts was 10:10:14 in the wet season and 11:10:10 in the dry season. The cock:hen ratio was 1:3.5. Average numbers of clutches per year ranged from 2.80-3.02 (average 2-94). The average number of eggs per clutch was 12 and consequently the number of eggs was 36 per hen/year. Hatchability was recorded to be 84.5. Chick mortality was found to be 30% and resulted mainly from diseases and predation. Out of 43 households interviewed, 23 kept their chickens in the chicken house, 12 within the family house, four in the kitchen/store, three kept their birds perched in trees and one used a woven basket. In all the households, scavenging was the system of feeding and sometimes supplemented by household scraps and other feeds. Poultry movement into the household's flocks resulting in mixing of birds from different flocks was rampant. Several diseases and in particular Newcastle disease were mentioned by farmers in both zones as the major constraints restricting rural chicken development. Other diseases included coughing/sneezing, fowl pox and parasitic diseases (helminths, external parasites, protozoa). Women played a major role in family poultry development through provision of labour, but men

  9. Mobile Sensing of Pedestrian Flocks in Indoor Environments using WiFi Signals

    DEFF Research Database (Denmark)

    Kjærgaard, Mikkel Baun; Wirz, Martin; Roggen, Daniel

    2012-01-01

    a cohesive whole - specifically flocks - with clustering approaches operating on three different feature sets derived from WiFi signals which are comparatively analysed. Automatic detection of flocks has several important applications, including social and psychological sensing and emergency research studies...

  10. THE STUDY OF THE ECONOMIC EFFICIENCY IN AMINO-ACIDS SUPPLEMENTATION OF THE LAYING HEN`S FODDER

    Directory of Open Access Journals (Sweden)

    ELIZA SIMIZ

    2007-05-01

    Full Text Available The experiment has been carried out on 69 Tetra SL hens, 27-36 weeks old, distributed into 3 groups consisted of 23 hens. They were fed with fodder recipes with different protein levels (17, 16 and respectively 15%. These recipes have been supplemented with DL-methionine and L-lysine up to the level of 0.80% lysine and 0.38% methionine. Fish flour has participated in a proportion of 3% in group 1, 1.5% in group 2 and it was absent from the fodder structure used in group 3. The reduction of crude protein with 1-2p% compared to the available commercial products, but with an amino acid supplementation, has led to the improvement of the economic criteria regarding egg production, generating savings of 7.7% in the group with 16% CP and of 12.8% in the group with 15% CP. The egg mass has not been affected significantly (p>0.05, the best yield being achieved from the hens fed with a 16%CP recipe.

  11. Depopulation of Caged Layer Hens with a Compressed Air Foam System.

    Science.gov (United States)

    Gurung, Shailesh; Hoffman, John; Stringfellow, Kendre; Abi-Ghanem, Daad; Zhao, Dan; Caldwell, David; Lee, Jason; Styles, Darrel; Berghman, Luc; Byrd, James; Farnell, Yuhua; Archer, Gregory; Farnell, Morgan

    2018-01-11

    During the 2014-2015 US highly pathogenic avian influenza (HPAI) outbreak, 50.4 million commercial layers and turkeys were affected, resulting in economic losses of $3.3 billion. Rapid depopulation of infected poultry is vital to contain and eradicate reportable diseases like HPAI. The hypothesis of the experiment was that a compressed air foam (CAF) system may be used as an alternative to carbon dioxide (CO₂) inhalation for depopulating caged layer hens. The objective of this study was to evaluate corticosterone (CORT) and time to cessation of movement (COM) of hens subjected to CAF, CO₂ inhalation, and negative control (NEG) treatments. In Experiment 1, two independent trials were conducted using young and spent hens. Experiment 1 consisted of five treatments: NEG, CO₂ added to a chamber, a CO₂ pre-charged chamber, CAF in cages, and CAF in a chamber. In Experiment 2, only spent hens were randomly assigned to three treatments: CAF in cages, CO₂ added to a chamber, and aspirated foam. Serum CORT levels of young hens were not significantly different among the CAF in cages, CAF in a chamber, NEG control, and CO₂ inhalation treatments. However, spent hens subjected to the CAF in a chamber had significantly higher CORT levels than birds in the rest of the treatments. Times to COM of spent hens subjected to CAF in cages and aspirated foam were significantly greater than of birds exposed to the CO₂ in a chamber treatment. These data suggest that applying CAF in cages is a viable alternative for layer hen depopulation during a reportable disease outbreak.

  12. Ochratoxicosis in White Leghorn breeder hens: Production and breeding performance

    Directory of Open Access Journals (Sweden)

    Zahoor Ul Hassan*, Muhammad Zargham Khan, Ahrar Khan, Ijaz Javed1, Umer Sadique2 and Aisha Khatoon

    2012-10-01

    Full Text Available This study was designed to evaluate the effect of Ochratoxin A (OTA upon production and breeding parameters in White Leghorn (WL breeder hens. For this purpose, 84 WL breeder hens were divided into seven groups (A-G. The hens in these groups were maintained on feed contaminated with OTA @ 0.0 (control, 0.1, 0.5, 1.0, 3.0, 5.0 and 10.0 mg/Kg, respectively for 21 days. These hens were artificially inseminated with semen obtained from healthy roosters kept on OTA free feed. Egg production and their quality parameters were recorded. Fertile eggs obtained from each group were set for incubation on weekly basis. At the end of the experiment, hens in each group were killed to determined gross and microscopic lesions in different organs. OTA residue concentrations were determined in extracts of liver, kidneys and breast muscles by immunoaffinity column elution and HPLC-Fluorescent detection techniques. Feeing OTA contaminated diet resulted in a significant decrease in egg mass and egg quality parameters. Liver and kidneys showed characteristic lesions of ochratoxicosis. Residue concentration (ng/g of OTA in the hens fed 10 mg/kg OTA, was the highest in liver (26.336±1.16 followed by kidney (8.223±0.85 and were least in breast muscles (1.235±0.21. Embryonic mortalites were higher, while hatachabilites of the chicks were lower in the groups fed higher doses of OTA. Feeding OTA contaminated diets to breeder hen resulted in residues accumulation in their tissues along with significantly reduced production and breeding performance.

  13. Spontaneous fluctuations in a zero-noise model of flocking

    Science.gov (United States)

    Chakraborty, Abhijit; Bhattacharya, Kunal

    2016-11-01

    Investigations into the complex structure and dynamics of collectively moving groups of living organisms have provided valuable insights. Understanding the emergent features, especially, the origin of fluctuations, appears to be challenging in the current scheme of models. It has been argued that flocks are poised at criticality. We present a two-dimensional self-propelled particle model where neighbourhoods and forces are defined through topology-based rules. The attractive forces are modeled in order to maintain cohesion in the flock in open-boundary conditions. We find that fluctuations occur spontaneously in the absence of any external noise. For certain values of the parameters the flock shows a high degree of order as well as scale-free decay of spatial correlations in velocity and speed. We characterize the dynamical behaviour of the system using the Lyapunov spectrum. Largest exponents being positive but small in magnitude suggest that the apparent high susceptibility may result from the system operating near the borderline of order and chaos.

  14. Early enrichment in free-range laying hens: effects on ranging behaviour, welfare and response to stressors.

    Science.gov (United States)

    Campbell, D L M; Hinch, G N; Downing, J A; Lee, C

    2018-03-01

    Free-range laying hen systems are increasing within Australia. The pullets for these systems are typically reared indoors before being provided first range access around 21 to 26 weeks of age. Thus, the rearing and laying environments are disparate and hens may not adapt well to free-range housing. In this study, we reared 290 Hy-Line® Brown day-old chicks divided into two rooms each with feed, water and litter. In the enriched room, multiple structural, manipulable, visual and auditory stimuli were also provided from 4 to 21 days, the non-enriched room had no additional objects or stimuli. Pullets were transferred to the laying facility at 12 weeks of age and divided into six pens (three enriched-reared, three non-enriched-reared) with identical indoor resources and outdoor range area. All birds were first provided range access at 21 weeks of age. Video observations of natural disturbance behaviours on the range at 22 to 23 and 33 to 34 weeks of age showed no differences in frequency of disturbance occurrences between treatment groups (P=0.09) but a decrease in disturbance occurrences over time (Prange each day (Prange visits than non-enriched birds from 21 to 24 weeks of age (P=0.01). Enriched birds accessed the range on more days (P=0.03) but over time, most birds in both treatment groups accessed the range daily. Basic external health scoring showed minimal differences between treatment groups with most birds in visibly good condition. At 38 weeks of age all birds were locked inside for 2 days and from 40 to 42 weeks of age the outdoor range was reduced to 20% of its original size to simulate stressful events. The eggs from non-enriched birds had higher corticosterone concentrations following lock-in and 2 weeks following range reduction compared with the concentrations within eggs from enriched birds (Prange area reduction compared to non-enriched hens (P=0.02). Only one rearing room per treatment was used but these preliminary data indicate 3 weeks of early

  15. Flocking Transition in Confluent Tissues

    Science.gov (United States)

    Paoluzzi, Matteo; Giavazzi, Fabio; Macchi, Marta; Scita, Giorgio; Cerbino, Roberto; Manning, Lisa; Marchetti, Cristina

    The emerging of collective migration in biological tissues plays a pivotal role in embryonic morphogenesis, wound healing and cancer invasion. While many aspects of single cell movements are well established, the mechanisms leading to coherent displacements of cohesive cell groups are still poorly understood. Some of us recently proposed a Self-Propelled Voronoi (SPV) model of dense tissues that combines self-propelled particle models and vertex models of confluent cell layers and exhibits a liquid-solid transition as a function of cell shape and cell motility. We now examine the role of cell polarization on collective cell dynamics by introducing an orientation mechanism that aligns cell polarization with local cell motility. The model predicts a density-independent flocking transition tuned by the strength of the aligning interaction, with both solid and liquid flocking states existing in different regions of parameter space. MP and MCM were supported by the Simons Foundation Targeted Grant in the Mathematical Modeling of Living Systems Number: 342354 and by the Syracuse Soft Matter Program.

  16. To flock or fight: neurochemical signatures of divergent life histories in sparrows.

    Science.gov (United States)

    Goodson, James L; Wilson, Leah C; Schrock, Sara E

    2012-06-26

    Many bird species exhibit dramatic seasonal switches between territoriality and flocking, but whereas neuroendocrine mechanisms of territorial aggression have been extensively studied, those of seasonal flocking are unknown. We collected brains in spring and winter from male field sparrows (Spizella pusilla), which seasonally flock, and male song sparrows (Melospiza melodia), which are territorial year-round in much of their range. Spring collections were preceded by field-based assessments of aggression. Tissue series were immunofluorescently multilabeled for vasotocin, mesotocin (MT), corticotropin-releasing hormone (CRH), vasoactive intestinal polypeptide, tyrosine hydroxylase, and aromatase, and labeling densities were measured in many socially relevant brain areas. Extensive seasonal differences are shared by both species. Many measures correlate significantly with both individual and species differences in aggression, likely reflecting evolved mechanisms that differentiate the less aggressive field sparrow from the more aggressive song sparrow. Winter-specific species differences include a substantial increase of MT and CRH immunoreactivity in the dorsal lateral septum (LS) and medial amygdala of field sparrows but not song sparrows. These species differences likely relate to flocking rather than the suppression of winter aggression in field sparrows, because similar winter differences were found for two other emberizids that are not territorial in winter--dark-eyed juncos (Junco hyemalis), which seasonally flock, and eastern towhees (Pipilo erythropthalmus), which do not flock. MT signaling in the dorsal LS is also associated with year-round species differences in grouping in estrildid finches, suggesting that common mechanisms are targeted during the evolution of different life histories.

  17. Evaluation of aflatoxicosis in hens fed with commercial poultry feed

    OpenAIRE

    DHANASEKARAN, Dharumadurai; PANNEERSELVAM, Annamalai; THAJUDDIN, Noorudin

    2014-01-01

    The effect of aflatoxin in the growth of hens was histopathologically analyzed. Mycotoxigenic fungi were isolated and characterized as Aspergillus flavus and Aspergillus niger. The aflatoxin was extracted from Aspergillus flavus and their impact on the growth pattern of hens was evaluated. The histopathological analysis reveals that more lesions were found in the vital organs of hens in comparison with the control chick group. In the present study, it is concluded that the quality of poultry ...

  18. Reduction of campylobacter infections in broiler flocks by application of hygiene measures

    NARCIS (Netherlands)

    Giessen, A.W. van de; Tilburg, J.J.H.C.; Ritmeester, W.S.; Plas, J. van der

    1998-01-01

    Transmission routes of Campylobacter spp. in broilers and possibilities for prevention of infections were studied on two Dutch broiler farms. The occurrence of Campylobacter spp. was studied in successive broiler flocks, in the environment of the farms and in some of the parent flocks involved.

  19. The Effect of Dietary Protein Levels in Growing Period on Performance at Onset of Lay of Crossbred Hens between Cockerel Native Chickens and Commercial Laying Hens

    Directory of Open Access Journals (Sweden)

    Harimurti Februari Trisiwi

    2017-11-01

    Full Text Available This research aims to examine the effects of various dietary protein levels during growing period crossbreed hens between cockerel native chickens and laying hens on performance at onset of lay. The effects of the dietary protein levels on weight and other components of eggs were also examined. Eighteen hens aged thirteen weeks were randomly divided into three different treatment groups. Each group consists of six replications. The replication contains a hen. All the treatment hens were grown in a battery-cage until reaching sexual maturity then were fed with three different dietary protein levels which are 13,54%, 12,00%, and 9,80% formulated with 2600 kcal/kg ME. The collected data were analyzed by a one-way classification of variance analysis (CRD followed by testing the significant means using The Duncan,s MultipleRange Test (DMRT. The experiment result suggested that the treatment during hen’s growing period did not cause significance on performance at onset lay, egg weight, and egg components weight.

  20. Depopulation of Caged Layer Hens with a Compressed Air Foam System

    Directory of Open Access Journals (Sweden)

    Shailesh Gurung

    2018-01-01

    Full Text Available During the 2014–2015 US highly pathogenic avian influenza (HPAI outbreak, 50.4 million commercial layers and turkeys were affected, resulting in economic losses of $3.3 billion. Rapid depopulation of infected poultry is vital to contain and eradicate reportable diseases like HPAI. The hypothesis of the experiment was that a compressed air foam (CAF system may be used as an alternative to carbon dioxide (CO2 inhalation for depopulating caged layer hens. The objective of this study was to evaluate corticosterone (CORT and time to cessation of movement (COM of hens subjected to CAF, CO2 inhalation, and negative control (NEG treatments. In Experiment 1, two independent trials were conducted using young and spent hens. Experiment 1 consisted of five treatments: NEG, CO2 added to a chamber, a CO2 pre-charged chamber, CAF in cages, and CAF in a chamber. In Experiment 2, only spent hens were randomly assigned to three treatments: CAF in cages, CO2 added to a chamber, and aspirated foam. Serum CORT levels of young hens were not significantly different among the CAF in cages, CAF in a chamber, NEG control, and CO2 inhalation treatments. However, spent hens subjected to the CAF in a chamber had significantly higher CORT levels than birds in the rest of the treatments. Times to COM of spent hens subjected to CAF in cages and aspirated foam were significantly greater than of birds exposed to the CO2 in a chamber treatment. These data suggest that applying CAF in cages is a viable alternative for layer hen depopulation during a reportable disease outbreak.

  1. Haematophagus Mites in Poultry Farms of Iran

    Directory of Open Access Journals (Sweden)

    S Rahbari

    2009-12-01

    Full Text Available Background: Blood sucking mites are important avian ectoparasites which being found on bird species worldwide. Their presence are problematic for the producers either through potential direct effects on weight gain, egg produc­tion, sperm production in roosters or as nuisance pests on worker handle hens and eggs. The aim of this study was pointing out of the status of haematophagus mites.Methods: Eight caged layer and four breeder flocks were visited, monitoring for the presence of chicken mites per­formed by removing and examining debris from poultry house, infested nesting material collected into zip lock plas­tic bags and at least 20 birds were also randomly selected to examine the presence of chicken mites. Mites obtained from each population were mounted in Hoyer,s medium on microscope slides and identified. All eight caged layer and four breeder flocks were inspected, which were infested with chicken blood feeding mites.Results: Massive infestations of Dermanyssus gallinae were common with huge numbers of parasites on birds, cages and the conveyor belts for egg. Only one farm from Mazandaran Province was infested to Ornithonyssus bursa.Conclusion: Dermanyssus gallinae was the most prevalent blood feeder mite in the breeder and caged layer flocks in Iran, while O. bursa was reported as a first record, which found only in a breeder flock in Mazanderan Province. It seems that its presence is limited into the area which affected by both warm and humid environmental conditions.

  2. Digestibility of organic processed feed ingredients in laying hens

    OpenAIRE

    van Krimpen, M.M.; van Diepen, J.T.M; Reuvekamp, B.F.J.; van Harn, J.

    2011-01-01

    In two experiments, digestibility and nutritive value for laying hens of organically-grown feed raw materials was assessed. Digestibility and metabolisable energy content of the products differed considerably compared to those listed in the CVB Feedstuff Table. Laying hens, organic feed raw materials, digestibility, nutritive value

  3. Anomalous behaviour of mutual information in finite flocks

    Science.gov (United States)

    Barnett, L.; Brown, J.; Bossomaier, T.

    2017-11-01

    The existing consensus is that flocks are poised at criticality, entailing long correlation lengths and a maximal value of Shannon mutual information in the large-system limit. We show, by contrast, that for finite flocks which do not truly break ergodicity in the long-observation-time limit, mutual information may not only fail to peak at criticality —as observed for other critical systems— but also diverge as noise tends to zero. This result carries implications for other finite-size, out-of-equilibrium systems, where observation times may vary widely compared to time scales of internal system dynamics; thus it may not be assumed that mutual information locates the phase transition.

  4. EGG QUALITY OF CREOLE HENS REARED IN THE BACKYARD

    Directory of Open Access Journals (Sweden)

    Aureliano Juárez-Caratachea

    2009-09-01

    Full Text Available The egg quality from Creole backyard hens was determined by collecting samples from 11 municipalities from the central area of Michoacan State, Mexico. It was measured: egg weight (EW, longitude diameter (LD of the egg, transversal diameter (TD of the egg, shell weight (SW, shell thickness (ST, shell index (SI, white diameter (WD, yolk diameter (YD, white high (WH, yolk high (YH, air chamber high (ACH and Haugh units (HU. The averages obtained were: EW 50.7 g; LD 5.6 cm; TD 4.2 cm; SW 4.5 g.; ST 0.28 mm; SI 8.9 %; WD 10.0 cm; YD 4.5 cm; WH 6.3 mm; YH 1.6 cm; ACH 5.4 mm; HU 73.4, YP 12.1. In conclusion, the eggs of backyard hens were smaller than commercial eggs. However, the internal quality indicators suggested that backyard hen eggs have similar quality to that of commercial hens.

  5. Nutrient digestibility and mass balance in laying hens fed a commercial or acidifying diet.

    Science.gov (United States)

    Wu-Haan, W; Powers, W J; Angel, C R; Hale, C E; Applegate, T J

    2007-04-01

    The objectives of the current study were to evaluate the effect of an acidifying diet (gypsum) combined with zeolite and slightly reduced crude protein (R) vs. a control diet (C) on nutrient retention in laying hens and compare 3 approaches to estimating nutrient excretion from hens: 1) mass balance calculation (feed nutrients - egg nutrient), 2) use of an indigestible marker with analyzed feed and excreta nutrient content, and 3) an environmental chamber that allowed for capturing all excreted and volatilized nutrients. Hens (n = 640) were allocated randomly to 8 environmental chambers for 3-wk periods. Excreta samples were collected at the end of each trial to estimate apparent retention of N, S, P, and Ca. No diet effects on apparent retention of N were observed (53.44%, P > 0.05). Apparent retention of S, P, and Ca decreased in hens fed R diet (18.7, - 11.4, and 22.6%, respectively) compared with hens fed the C diet (40.7, 0.3, and 28.6%, respectively; P < 0.05). Total N excretion from hens fed the C and R diet was not different (1.16 g/hen/d); however, mass of chamber N remaining in excreta following the 3-wk period was less from hens fed the C diet (1.27 kg) than from hens fed the R diet (1.43 kg). Gaseous emissions of NH(3) over the 3-wk period from hens fed the C diet (0.74 kg per chamber) were greater than emissions from hens fed the R diet (0.45 kg). The 3-wk S excretion mass (estimated using the calculation, indigestible marker, and environmental chamber methods, respectively) was greater from hens fed the R diet (1.85, 1.54, and 1.27 kg, respectively) compared with hens fed the C diet (0.24, 0.20, and 0.14 kg, respectively). The 3-wk P excretion was similar between diets (0.68 kg). Results demonstrate that feeding the acidified diet resulted in decreased N emissions, but because of the acidulant fed, greatly increased S excretion and emissions.

  6. Brucellosis outbreak in a flock of seventeen sheep in Zaria | Onoja ...

    African Journals Online (AJOL)

    This work is a case report of brucellosis in a flock of sheep in Zaria. The flock comprised of seventeen Yankasa sheep, 14 ewes and 3 rams, with history of 2 recent cases of abortion, a presented case of uterine prolapse and 3 cases of carpal hygroma (1st and 2nd sheep bilaterally and the 3rd sheep left unilaterally).

  7. Within-Flock Population Dynamics of Dichelobacter nodosus

    Directory of Open Access Journals (Sweden)

    Laura E. Green

    2017-04-01

    Full Text Available Footrot causes 70–90% of lameness in sheep in Great Britain. With approximately 5% of 18 million adult sheep lame at any one time, it costs the UK sheep industry £24–84 million per year. The Gram-negative anaerobe Dichelobacter nodosus is the causative agent, with disease severity influenced by bacterial load, virulence, and climate. The aim of the current study was to characterize strains of D. nodosus isolated by culture of swabs from healthy and diseased feet of 99 ewes kept as a closed flock over a 10-month period and investigate persistence and transmission of strains within feet, sheep, and the flock. Overall 268 isolates were characterized into strains by serogroup, proline–glycine repeat (pgr status, and multi-locus variable number tandem repeat analysis (MLVA. The culture collection contained 87 unique MLVA profiles and two major MLVA complexes that persisted over time. A subset of 189 isolates tested for the virulence marker aprV2 were all positive. The two MLVA complexes (76 and 114 comprised 62 and 22 MLVA types and 237 and 28 isolates, respectively. Serogroups B, and I, and pgrB were associated with MLVA complex 76, whereas serogroups D and H were associated with MLVA complex 114. We conclude that within-flock D. nodosus evolution appeared to be driven by clonal diversification. There was no association (P > 0.05 between serogroup, pgr, or MLVA type and disease state of feet. Strains of D. nodosus clustered within sheep and were transmitted between ewes over time. D. nodosus was isolated at more than one time point from 21 feet, including 5 feet where the same strain was isolated on two occasions at an interval of 1–33 weeks. Collectively, our results indicate that D. nodosus strains persisted in the flock, spread between sheep, and possibly persisted on feet over time.

  8. Cyclic and Coherent States in Flocks with Topological Distance

    Science.gov (United States)

    Bhattacherjee, Biplab; Bhattacharya, Kunal; Manna, Subhrangshu

    2014-01-01

    A simple model of the two dimensional collective motion of a group of mobile agents have been studied. Like birds, these agents travel in open free space where each of them interacts with the first n neighbors determined by the topological distance with a free boundary condition. Using the same prescription for interactions used in the Vicsek model with scalar noise it has been observed that the flock, in absence of the noise, arrives at a number of interesting stationary states. One of the two most prominent states is the `single sink state' where the entire flock travels along the same direction maintaining perfect cohesion and coherence. The other state is the `cyclic state' where every individual agent executes a uniform circular motion, and the correlation among the agents guarantees that the entire flock executes a pulsating dynamics i.e., expands and contracts periodically between a minimum and a maximum size of the flock. We have studied another limiting situation when refreshing rate of the interaction zone is the fastest. In this case the entire flock gets fragmented into smaller clusters of different sizes. On introduction of scalar noise a crossover is observed when the agents cross over from a ballistic motion to a diffusive motion. Expectedly the crossover time is dependent on the strength of the noise η and diverges as η → 0. An even more simpler version of this model has been studied by suppressing the translational degrees of freedom of the agents but retaining their angular motion. Here agents are the spins, placed at the sites of a square lattice with periodic boundary condition. Every spin interacts with its n = 2, 3 or 4 nearest neighbors. In the stationary state the entire spin pattern moves as a whole when interactions are anisotropic with n = 2 and 3; but it is completely frozen when the interaction is isotropic with n=4$. These spin configu

  9. Cyclic and Coherent States in Flocks with Topological Distance

    Directory of Open Access Journals (Sweden)

    Biplab eBhattacherjee

    2014-01-01

    Full Text Available A simple model of the two dimensional collective motion of a group of mobile agents have been studied. Like birds, these agents travel in open free space where each of them interacts with the first $n$ neighbors determined by the topological distance with a free boundary condition. Using the same prescription for interactions used in the Vicsek model with scalar noise it has been observed that the flock, in absence of the noise, arrives at a number of interesting stationary states. One of the two most prominent states is the `single sink state' where the entire flock travels along the same direction maintaining perfect cohesion and coherence. The other state is the `cyclic state' where every individual agent executes a uniform circular motion, and the correlation among the agents guarantees that the entire flock executes a pulsating dynamics i.e., expands and contracts periodically between a minimum and a maximum size of the flock. We have studied another limiting situation when refreshing rate of the interaction zone is the fastest. In this case the entire flock gets fragmented into smaller clusters of different sizes. On introduction of scalar noise a crossover is observed when the agents cross over from a ballistic motion to a diffusive motion. Expectedly the crossover time is dependent on the strength of the noise $eta$ and diverges as $eta to 0$. An even more simpler version of this model has been studied by suppressing the translational degrees of freedom of the agents but retaining their angular motion. Here agents are the spins, placed at the sites of a square lattice with periodic boundary condition. Every spin interacts with its $n$ = 2, 3 or 4 nearest neighbors. In the stationary state the entire spin pattern moves as a whole when interactions are anisotropic with $n$ = 2 and 3; but it is completely frozen when the interaction is isotropic with $n=4$. These spin configu

  10. Vold, svensk uro og Henning Mankell

    DEFF Research Database (Denmark)

    Hansen, Kim Toft

    Paperet undersøger den fiktionelle repræsentation af vold hos Henning Mankell med fokus på Innan frosten fra 2002 og filmatiseringen heraf fra 2005, men med fyldige udblik til såvel andre af Mankells fortællinger og ikke mindst sociologiske og filosofiske diskussioner af volden, voldens forstyrre......Paperet undersøger den fiktionelle repræsentation af vold hos Henning Mankell med fokus på Innan frosten fra 2002 og filmatiseringen heraf fra 2005, men med fyldige udblik til såvel andre af Mankells fortællinger og ikke mindst sociologiske og filosofiske diskussioner af volden, voldens...

  11. Occurrence of quinolone- and beta-lactam-resistant Escherichia coli in danish broiler flocks

    DEFF Research Database (Denmark)

    Bortolaia, Valeria; Guardabassi, Luca; Bisgaard, Magne

    An increased concern for the possible transfer of resistant bacteria or mobile resistance elements from food animals to humans has resulted in rigorous legislation preventing i.e. practical use of fluoroquinolones in the Danish broiler industry (Olesen et al., 2004; Petersen et al., 2006...... and nalidixic acid resistances were detected in all flocks. The numbers of E. coli resistant to these drugs were higher in plates from parent flocks than in those from offspring flocks. A broiler parent flock without any history of quinolone usage tested positive for ciprofloxacin-resistant E. coli, although...... and mutations responsible for these types of resistance. References DANMAP 2005. 2006. Use of antimicrobial agents and occurrence of antimicrobial resistance in bacteria from food animals, foods and humans in Denmark. Danish Veterinary Laboratory, Copenhagen, Denmark, ISSN 1600-2032. Olesen, I., H. Hasman...

  12. Microclimate measuring and fluid‑dynamic simulation in an industrial broiler house: testing of an experimental ventilation system.

    Science.gov (United States)

    Bianchi, Biagio; Giametta, Ferruccio; La Fianza, Giovanna; Gentile, Andrea; Catalano, Pasquale

    2015-01-01

    The environment in the broiler house is a combination of physical and biological factors generating a complex dynamic system of interactions between birds, husbandry system, light, temperature, and the aerial environment. Ventilation plays a key role in this scenario. It is pivotal to remove carbon dioxide and water vapor from the air of the hen house. Adequate ventilation rates provide the most effective method of controlling temperature within the hen house. They allow for controlling the relative humidity and can play a key role in alleviating the negative effects of high stocking density and of wet litter. In the present study the results of experimental tests performed in a breeding broiler farm are shown. In particular the efficiency of a semi transversal ventilation system was studied against the use of a pure transversal one. In order to verify the efficiency of the systems, fluid dynamic simulations were carried out using the software Comsol multiphysics. The results of this study show that a correct architectural and structural design of the building must be supported by a design of the ventilation system able to maintain the environmental parameters within the limits of the thermo‑neutral and welfare conditions and to achieve the highest levels of productivity.

  13. PRODUCTIVITY OF LAYERS AND EGG QUALITY IN FREE RANGE AND CAGE SYSTEM OF HOUSING

    Directory of Open Access Journals (Sweden)

    Đ. Senčić

    2006-12-01

    Full Text Available The research was conducted with two groups of Lohmann Brown hybrid layers. Production of eggs lasted for 52 weeks. A control group of layers was kept in the conventional housing system, that is, in cages, while experimental group was kept in the free range system. Layers from the free range system, compared to those kept in cages, laid fewer eggs, (266:295, they consumed more feed on daily basis (129 g : 115 g, more feed per kilogram of egg weight (2.83 kg : 2.35 kg, they had higher mortality rate (6.80 % : 5.50 % and lower end of lay body weight (1.95 kg : 2.10 kg. Eggs from free range layers, compared to those from the cages system, had significantly (P0.05 were determined between the free range and the cages system of housing hens. Considering somewhat lower productivity and higher mortality rate of hens, higher feed consumption per kilogram of egg mass, but also better quality of eggs, profitability of egg production in the free range system will depend, to the maximum extent, on market evaluation of the production.

  14. Organic Turkey Flocks: A Reservoir of Streptococcus gallolyticus subspecies gallolyticus.

    Directory of Open Access Journals (Sweden)

    Jochen Schulz

    Full Text Available Streptococcus gallolyticus subspecies gallolyticus (S. gallolyticus can colonise the gastrointestinal tract of humans and animals and is known to cause similar infections in both humans and animals. Data about the spread or prevalence in farm animals are missing. In this study, Trypton Soya Agar was modified to a selective medium enabling the isolation and quantification of S. gallolyticus from faecal samples. The bacterium was observed in 82 out of 91 faecal samples obtained from 18 different organic turkey flocks. The prevalence of shedding birds was estimated by the number of positive fresh droppings and reached up to 100% on most farms. Furthermore, for the first time S. gallolyticus was quantified in faeces from poultry flocks. The median of colony forming units (CFU per gramme faeces was 3.6 x 10(5 CFU/g. Typing of one isolate from each positive faecal sample by multilocus sequence typing delivered 24 sequence types (STs. Most of the isolates belonged to the clonal complex CC58. The same STs of this complex were detected in up to six different flocks. Partly, these flocks were located in various regions and stocked with varying breeding lines. Regarding the biochemical profiles of the same STs from different farms, the results did not contradict a spread of specific STs in the organic turkey production. Moreover, checking the pubMLST database revealed that STs found in this study were also found in other animal species and in humans. The high detection rate and the number of S. gallolyticus in turkey faeces indicate that this bacterium probably belongs to the common microbiota of the gastrointestinal tract of turkeys from organic flocks. Furthermore, the findings of this study support the suggestion of a possible interspecies transmission.

  15. The influence of different single dietary sources on moult induction in laying hens.

    Science.gov (United States)

    Mansoori, Behzad; Modirsanei, Mehrdad; Farkhoy, Mohsen; Kiaei, Mohammad-Mehdi; Honarzad, Jila

    2007-11-01

    An investigation was carried out to assess the possibility of using single dietary sources as alternatives to feed deprivation for the induction of moult in commercial laying hens. The study involved six dietary groups of 29 laying hens: unmoulted, dried tomato pomace, alfalfa meal, rice bran, cumin seed meal and feed withdrawal. The birds received the above diets during the moulting period (11 days), and body weight loss and ovary weight regression were measured. Post-moult production parameters (number of eggs produced per hen per day, egg weight, shell weight, yolk colour and Haugh unit) were measured for 12 weeks. Results showed that all dietary sources were as effective as feed withdrawal in causing ovary weight regression in birds. Birds provided with tomato pomace or alfalfa showed lower weight losses than feed-deprived birds at the end of the moulting period. Hens moulted by tomato pomace or alfalfa exhibited post-moult levels of egg production over a 12 week period that were superior to those of hens moulted by feed withdrawal. Post-moult eggs laid by hens moulted by all dietary sources were of comparable quality to eggs from feed-deprived hens and superior to those from unmoulted hens. As fibrous feeds with low metabolisable energy and an appreciable amount of protein, dried tomato pomace and alfalfa meal may be fed to hens on an ad libitum basis for effective moult induction while reducing the stress of severe starvation and retaining comparable egg quality and production. Copyright © 2007 Society of Chemical Industry.

  16. Prevalence and characterization of Campylobacter jejuni isolated from pasture flock poultry.

    Science.gov (United States)

    Hanning, Irene; Biswas, Debabrata; Herrera, Paul; Roesler, Mary; Ricke, Steven C

    2010-09-01

    The growing interest in organic and natural foods warrants a greater need for information on the food safety of these products. In this study, samples were taken from 2 pasture flock farms (N = 178; feed, water, drag swabs, and insect traps), pasture flock retail carcasses (N = 48) and 1 pasture flock processing facility (N = 16) over a period of 8 mo. A total of 105 Campylobacter isolates were obtained from 53 (30%), 36 (75%), and 16 (100%) samples from the farms, retail carcasses, and processing facility, respectively. Of the 105 isolates collected, 65 were C. jejuni, 31 were C. coli, and 9 were other Campylobacter spp. Using PCR, the C. jejuni isolates were further analyzed for virulence genes involved in colonization and survival (flaA, flaC, cadF, dnaJ, racR, cbrR), invasion (virB11, ciaB, pldA), protection against harsh conditions (sodB, htrA, clpA), toxin production (cdtA, cdtB, cdtC), siderophore transport (ceuE), and ganglioside mimicry (wlaN). In addition, the short variable region of the flaA locus (flaA SVR) was sequenced to determine the genetic diversity of the C. jejuni isolates. The flaA SVR diversity indices increased along the farm to carcass continuum. PCR-based analysis indicated a low prevalence of 5 genes involved in colonization (dnaJ, ciaB, pldA, racR, virB11). The results of this survey indicate that the prevalence of Campylobacter on organic retail carcasses is similar to prevalence reports of Campylobacter on conventional retail carcasses. However, the genetic diversity of the flaA SVR genotypes increased along the farm to carcass continuum that contrasted with conventional poultry studies. Campylobacter jejuni is a leading cause of foodborne illness with poultry and poultry products being leading sources of infection. Free-range and pasture flock chickens are becoming more popular; however, there is an inherent biosecurity risk that can increase the prevalence of foodborne pathogens in these flocks. This study aimed to determine sources

  17. Epidemiology, production losses, and control measures associated with an outbreak of avian influenza subtype H7N2 in Pennsylvania (1996-98).

    Science.gov (United States)

    Henzler, D J; Kradel, D C; Davison, S; Ziegler, A F; Singletary, D; DeBok, P; Castro, A E; Lu, H; Eckroade, R; Swayne, D; Lagoda, W; Schmucker, B; Nesselrodt, A

    2003-01-01

    An outbreak of H7N2 low-pathogenicity (LP) avian influenza (AI) occurred in a two-county area in Pennsylvania from December of 1996 through April of 1998. The outbreak resulted in infection of 2,623,116 commercial birds on 25 premises encompassing 47 flocks. Twenty-one (one premise with infection twice) of the twenty-five infected premises housed egg-laying chickens and one premise each had turkeys, layer pullets, quail, and a mixed backyard dealer flock. Despite dose proximity of infected flocks to commercial broiler flocks, no infected broilers were identified. Experimentally, when market age broilers were placed on an influenza-infected premise they seroconverted and developed oviduct lesions. The outbreak was believed to have originated from two separate introductions into commercial layer flocks from premises and by individuals dealing in sales of live fowl in the metropolitan New York and New Jersey live-bird markets. Source flocks for these markets are primarily in the northeast and mid-Atlantic areas, including Pennsylvania. Mixed fowl sold include ducks, geese, guinea hens, quail, chukar partridges, and a variety of chickens grown on perhaps hundreds of small farms. Infections with the H7N2 AI virus were associated with variable morbidity and temporary decreases in egg production ranging from 1.6% to 29.1% in commercial egg-laying chickens. Egg production losses averaged 4.0 weeks duration. Mortality ranged from 1.5 to 18.3 times normal (mean of 4.3 times normal). Duration of mortality ranged from 2 to 13 weeks (average of 3.9 weeks) in flocks not depopulated. Lesions observed were primarily oviducts filled with a mucous and white gelatinous exudates and atypical egg yolk peritonitis. Quarantine of premises and complete depopulation were the early measures employed in control of this outbreak. Epidemiological studies suggested that depopulation furthered the spread of influenza to nearby flocks. Thereafter, later control measures included quarantine

  18. Functional Traits, Flocking Propensity, and Perceived Predation Risk in an Amazonian Understory Bird Community.

    Science.gov (United States)

    Martínez, Ari E; Gomez, Juan P; Ponciano, José Miguel; Robinson, Scott K

    2016-05-01

    Within a community, different species might share similar predation risks, and, thus, the ability of species to signal and interpret heterospecific threat information may determine species' associations. We combined observational, experimental, and phylogenetic approaches to determine the extent to which evolutionary history and functional traits determined flocking propensity and perceived predation risk (response to heterospecific alarm calls) in a lowland Amazonian bird community. We predicted that small birds that feed myopically and out in the open would have higher flocking propensities and account for a higher proportion of positive responses to alarms. Using generalized linear models and the incorporation of phylogeny on data from 56 species, our results suggest that phylogenetic relationships alongside body size, foraging height, vegetation density, and response to alarm calls influence flocking propensity. Conversely, phylogenetic relationships did not influence response to heterospecific alarm calls. Among functional traits, however, foraging strategy, foraging density, and flocking propensity partially explained responses to alarm calls. Our results suggest that flocking propensity and perceived predation risk are positively related and that functional ecological traits and evolutionary history may explain certain species' associations.

  19. Genetic analysis of feather pecking behavior in laying hens

    NARCIS (Netherlands)

    Buitenhuis, A.J.

    2003-01-01

    This thesis describes the genetic analysis of feather pecking behavior in laying hens. Feather pecking (FP) is a major welfare problem in laying hens.In the European

  20. Aflatoxins, hydroxylated metabolites, and aflatoxicol from breast muscle of laying hens.

    Science.gov (United States)

    Díaz-Zaragoza, M; Carvajal-Moreno, M; Méndez-Ramírez, I; Chilpa-Galván, N C; Avila-González, E; Flores-Ortiz, C M

    2014-12-01

    Aflatoxins (AF) are toxic fungal secondary metabolites that are pathological to animals and humans. This study identified and quantified AF (AFB(1), AFB(2), AFG(1), AFG(2)) and their hydroxylated metabolites (AFM(1), AFM(2), AFP(1)) and aflatoxicol (AFL) from laying hen breast muscles. Aflatoxins pass from cereal feed to the laying hen tissues, causing economic losses, and from there to humans. To detect the passage of AF from feed to hen breast muscle tissues, an experiment that included 25 Hy-Line W36 121-wk-old hens was performed for 8 d. Hens in individual cages were distributed into 3 groups: a control group, with feed free of AFB(1), and 2 experimental groups, with feed spiked with 2 AFB(1) dosages: 30 µg·kg(-1) (low) or 500 µg·kg(-1) (high). The daily feed consumption per hen was recorded and afterward hens were euthanized and breast muscles were collected, weighed, and dried individually. Aflatoxins were extracted by 2 chemical methods and quantified by HPLC. Both methods were validated by lineality (calibration curves), recovery percentage (>80%), limit of detection, and limit of quantification. The AF (µg·kg(-1)) averages recovered in control breast muscles were as follows: AFB(1) (18); AFG(1), AFM(2), and AFL (0); AFG(2) (1.3); AFM(1) (52), and AFP1 (79). Hens fed with feed spiked with 30 µg·kg(-1) of AFB(1) had AFG(1) (16); AFG(2) (72); AFM(1) (0); AFM(2) (18); AFP(1) (145); and AFL (5 µg·kg(-1)). Hens with feed spiked with 500 µg·kg(-1) of AFB(1) had AFG(1) (512); AFG(2) (7); AFM(1) (4,775); AFM(2) (0); AFP(1) (661); and AFL (21 µg·kg(-1)). The best AF extraction method was Qian and Yang's method, modified by adding additional AF from both Supelclean LC18 SPE columns; its limit of detection (0.5 ng·mL(-1)) was lower compared with that of Koeltzow and Tanner, which was 1 ng·mL(-1). ©2014 Poultry Science Association Inc.

  1. THE PERFORMANCE OF LAYING HENS FED DIFFERENT CALCIUM SOURCE

    Directory of Open Access Journals (Sweden)

    S. Kismiati

    2012-12-01

    Full Text Available The research was aimed to evaluate the performance of laying hens fed different calcium sources. Two hundreds of Isa Brown laying hens were used in this study. The hens were raised in individual battery cages units for 12 weeks. Four calcium source (limestone as a control, 5% limestone + 2.5% eggshells waste, 2.5% limestone + 5% eggshells waste and 7.5% eggshell waste were used in feed experiment. A completely randomized design was applied, with 4 treatments and 5 replications. Each experimental unit consisted of 10 laying hens. The parameters measured were feed intake, protein intake, calcium intake, phosphorus intake, egg production, egg weight and feed conversion ratio. Results of the research showed that the calcium source had significantly effect on performance productions. The use of eggshell waste 7.5% significantly increased the feed intake, calcium intake, phosphorus intake, egg production and egg weight except for feed conversion ratio. The conclusion of this research was that the use of eggshell waste as calcium source of feed resulted in better performance than using limestone or mixed limestone with eggshell waste.

  2. Distance Constrained Based Adaptive Flocking Control for Multiagent Networks with Time Delay

    Directory of Open Access Journals (Sweden)

    Qing Zhang

    2015-01-01

    Full Text Available The flocking control of multiagent system is a new type of decentralized control method, which has aroused great attention. The paper includes a detailed research in terms of distance constrained based adaptive flocking control for multiagent system with time delay. Firstly, the program on the adaptive flocking with time delay of multiagent is proposed. Secondly, a kind of adaptive controllers and updating laws are presented. According to the Lyapunov stability theory, it is proved that the distance between agents can be larger than a constant during the motion evolution. What is more, velocities of each agent come to the same asymptotically. Finally, the analytical results can be verified by a numerical example.

  3. Modeling and Flocking Consensus Analysis for Large-Scale UAV Swarms

    Directory of Open Access Journals (Sweden)

    Li Bing

    2013-01-01

    Full Text Available Recently, distributed coordination control of the unmanned aerial vehicle (UAV swarms has been a particularly active topic in intelligent system field. In this paper, through understanding the emergent mechanism of the complex system, further research on the flocking and the dynamic characteristic of UAV swarms will be given. Firstly, this paper analyzes the current researches and existent problems of UAV swarms. Afterwards, by the theory of stochastic process and supplemented variables, a differential-integral model is established, converting the system model into Volterra integral equation. The existence and uniqueness of the solution of the system are discussed. Then the flocking control law is given based on artificial potential with system consensus. At last, we analyze the stability of the proposed flocking control algorithm based on the Lyapunov approach and prove that the system in a limited time can converge to the consensus direction of the velocity. Simulation results are provided to verify the conclusion.

  4. Application of Paracoccus marcusii as a potential feed additive for laying hens.

    Science.gov (United States)

    Conradie, Tersia A; Pieterse, Elsje; Jacobs, Karin

    2018-03-01

    Carotenoids have been used for many years as an added pigment to enhance egg yolk color. One such carotenoid, astaxanthin, has a strong antioxidant activity and is produced by several microorganisms, including the bacterium Paracoccus marcusii, which has shown promise to be used as a feed additive. Therefore, this study investigated the use of P. marcusii as a possible source of pigmentation in layer hen feed to enhance egg yolk color. Paracoccus marcusii was fed to hens in a sucrose solution (10% m/v). The hens were fed daily and all eggs were collected for analysis. Dilutions of egg contents were plated onto selective media to detect the presence of known food pathogens (E. coli, Listeria, and Salmonella). In the feeding trial, there was no negative effect on hen body weight, egg production, or overall egg quality. There was a significant increase (P feed additive for laying hens.

  5. Selected pharmacokinetic parameters for cefovecin in hens and green iguanas

    DEFF Research Database (Denmark)

    Thuesen, Line Risager; Bertelsen, Mads Frost; Brimer, Leon

    2009-01-01

    hens and green iguanas, following subcutaneous injections with 10 mg cefovecin / kg bodyweight. Preliminary studies in eight additional species of birds and reptiles were performed and results were compared with the parameters found in hens and green iguanas. The kinetics were characterized by rapid...

  6. Quinolone- and ß-lactam-resistance in Escherichia coli from Danish and Italian broiler flocks

    DEFF Research Database (Denmark)

    Bortolaia, Valeria; Guardabassi, Luca; Bisgaard, Magne

    /ml), ampicillin (32 µg/ml), cefotaxime (2 µg/ml) or ceftiofur (8 µg/ml). The ß-glucuronidase test was performed for verification of presumptive E. coli. The same methods were used to analyse sock samples collected from six Italian broiler flocks. PCR with primers for the CTX-M-type ESBLs was performed...... usage and none of the flocks was positive for cephalosporin-resistant E. coli. In Italy, resistance to ciprofloxacin was detected in all flocks and resistances to ceftiofur and cefotaxime were detected in five flocks. Primers specific for the CTX-M-type ESBLs generated PCR amplicons from isolates from...

  7. Radiocaesium activity in sheep: variation within flocks and with time

    International Nuclear Information System (INIS)

    Pearce, J.; Moss, B.W.; Colgan, P.A.; Scully, B.J.

    1990-01-01

    The radiocaesium levels in sheep, assessed by in vivo monitoring, increased rapidly and in a parallel manner in both lambs and ewes grazing upland pasture in Ireland known to be contaminated with post-Chernobyl fallout for at least 10 weeks after the animals were moved on to this pasture. Considerable variability was noted in the individual animal radiocaesium values within all the flocks studied. A comparison of the radiocaesium contents of some flocks in 1987, 1988 and 1989 show similar values for the different years. (author)

  8. Effect of replacing dietary vitamin E by sage on performance and meatiness of spent hens, and the oxidative stability of sausages produced from their meat.

    Science.gov (United States)

    Loetscher, Y; Kreuzer, M; Albiker, D; Stephan, R; Messikommer, R E

    2014-01-01

    A total of 3960 hens (half ISA Warren and half Dekalb White) were housed in 18 compartments with 220 hens each. The effect of replacing dietary vitamin E by sage on productivity, meat yield and oxidative stability of sausages was studied. One third of all animals received either a vitamin E deficient diet (negative control) or diets supplemented with 30 mg/kg α-tocopherylacetate (positive control) or 25 g sage leaves/kg. At slaughter, meat yield was assessed and sausages were produced (n = 12 per treatment). The omission of vitamin E did not impair the oxidative stability of the raw sausage material or the spiced sausages in comparison to the positive control. Sage supplementation improved oxidative stability after 7 m of frozen storage, but not after 1, 4 and 10 m. Spice addition during meat processing had an antioxidant effect regardless of dietary treatment. Diet supplementation of any type did not affect laying performance and sausage meat yield. Feeding antioxidants to spent hens seemed to be not as efficient as in growing chickens, while seasoning with spices during sausage production proved to be a feasible way to delay lipid oxidation.

  9. Fluctuation-driven flocking movement in three dimensions and scale-free correlation.

    Science.gov (United States)

    Niizato, Takayuki; Gunji, Yukio-Pegio

    2012-01-01

    Recent advances in the study of flocking behavior have permitted more sophisticated analyses than previously possible. The concepts of "topological distances" and "scale-free correlations" are important developments that have contributed to this improvement. These concepts require us to reconsider the notion of a neighborhood when applied to theoretical models. Previous work has assumed that individuals interact with neighbors within a certain radius (called the "metric distance"). However, other work has shown that, assuming topological interactions, starlings interact on average with the six or seven nearest neighbors within a flock. Accounting for this observation, we previously proposed a metric-topological interaction model in two dimensions. The goal of our model was to unite these two interaction components, the metric distance and the topological distance, into one rule. In our previous study, we demonstrated that the metric-topological interaction model could explain a real bird flocking phenomenon called scale-free correlation, which was first reported by Cavagna et al. In this study, we extended our model to three dimensions while also accounting for variations in speed. This three-dimensional metric-topological interaction model displayed scale-free correlation for velocity and orientation. Finally, we introduced an additional new feature of the model, namely, that a flock can store and release its fluctuations.

  10. Fluctuation-driven flocking movement in three dimensions and scale-free correlation.

    Directory of Open Access Journals (Sweden)

    Takayuki Niizato

    Full Text Available Recent advances in the study of flocking behavior have permitted more sophisticated analyses than previously possible. The concepts of "topological distances" and "scale-free correlations" are important developments that have contributed to this improvement. These concepts require us to reconsider the notion of a neighborhood when applied to theoretical models. Previous work has assumed that individuals interact with neighbors within a certain radius (called the "metric distance". However, other work has shown that, assuming topological interactions, starlings interact on average with the six or seven nearest neighbors within a flock. Accounting for this observation, we previously proposed a metric-topological interaction model in two dimensions. The goal of our model was to unite these two interaction components, the metric distance and the topological distance, into one rule. In our previous study, we demonstrated that the metric-topological interaction model could explain a real bird flocking phenomenon called scale-free correlation, which was first reported by Cavagna et al. In this study, we extended our model to three dimensions while also accounting for variations in speed. This three-dimensional metric-topological interaction model displayed scale-free correlation for velocity and orientation. Finally, we introduced an additional new feature of the model, namely, that a flock can store and release its fluctuations.

  11. Chemical features, cholesterol and energy content of table hen eggs ...

    African Journals Online (AJOL)

    Chemical features, cholesterol and energy content of table hen eggs from conventional and alternative farming systems. ... South African Journal of Animal Science ... This study was carried out to investigate the effect of conventional farming systems for laying hens (standard cage batteries) and new alternative systems ...

  12. Effect of production system and flock age on eggshell and egg internal quality measurements.

    Science.gov (United States)

    Samiullah, Sami; Omar, Amal Saleh; Roberts, Juliet; Chousalkar, Kapil

    2017-01-01

    Egg quality was measured in eggs from different flocks that were reared together and then allocated to different production systems. Eggs were processed for measurements of eggshell and egg internal quality variables, scoring of ultrastructural mammillary layer features, completeness of cuticle cover, and protoporphyrin IX (PP IX) quantification. There was a significant main effect (P egg weight, and egg internal quality and significant effects of flock age on most measurements. The mammillary layer ultrastructural variables showed no clear relationship with production system and flock age. However, there was a significant interaction between production system and flock age for mammillary cap, early and late fusions. Cuticle cover ([Formula: see text]), was significantly higher in barn eggs (19.20), followed by free range (17.57), and cage eggs (15.99). Completeness of cuticle cover was significantly higher in eggs from the 44 week old flock than for 64 week and 73 week old flocks. For eggshells with cuticle intact, there was a significant main effect of both production system and flock age, and significant interaction between the two, for shell reflectivity, L*a*b* values and amount of PP IX. For PP IX, when this difference was calculated for the cuticle alone, there were no statistically significant differences. In 1 g of shell with and without cuticle, there was more PP IX in cage eggs (9.49 × 10 -8 , 7.90 × 10 -8  mM) followed by free range (8.24 × 10 -8 , 6.90 × 10 -8  mM), and barn eggs (8.64 × 10 -8 , 7.28 × 10 -8  mM). Similar trends were recorded for the amount of PP IX in 1 g of cuticle, but the difference was not statistically significant. The amount of PP IX decreased significantly with increasing flock age. Comparing the cage and barn production systems at 68 week of flock age, there was no difference for the amount of PP IX in shell with or without cuticle, or in the cuticle alone. Eggs from the cage production system were darker in color

  13. Spatial Cognition and Range Use in Free-Range Laying Hens.

    Science.gov (United States)

    Campbell, Dana L M; Talk, Andrew C; Loh, Ziyang A; Dyall, Tim R; Lee, Caroline

    2018-02-08

    Radio-frequency identification tracking shows individual free-range laying hens vary in range use, with some never going outdoors. The range is typically more environmentally complex, requiring navigation to return to the indoor resources. Outdoor-preferring hens may have improved spatial abilities compared to indoor-preferring hens. Experiment 1 tested 32 adult ISA Brown hens in a T-maze learning task that showed exclusively-indoor birds were slowest to reach the learning success criterion ( p 0.05), the age that coincided with the onset of lay. Enriched birds that were faster to learn the maze task showed more range visits in the first 4 weeks of range access. Enriched and non-enriched birds showed no differences in telencephalon or hippocampal volume ( p > 0.05). Fear may reduce spatial abilities but further testing with more pen replicates per early rearing treatments would improve our understanding of the relationship between spatial cognitive abilities and range use.

  14. Conium maculatum (poison hemlock) toxicosis in a flock of range turkeys.

    Science.gov (United States)

    Frank, A A; Reed, W M

    1987-01-01

    Five 20-week-old tom turkeys from a flock of range turkeys were presented for examination; the flock had a history of salivation, tremors, paralysis, and increased mortality. Necropsy revealed numerous seeds identified as seeds from Conium maculatum (poison hemlock) within the crop, proventriculus, and gizzard. Histopathologic alterations were limited to catarrhal enteritis. Clinical signs of Conium maculatum toxicosis abated after the turkeys were removed from their range, which was infested with poison hemlock.

  15. A flocking algorithm for multi-agent systems with connectivity preservation under hybrid metric-topological interactions.

    Science.gov (United States)

    He, Chenlong; Feng, Zuren; Ren, Zhigang

    2018-01-01

    In this paper, we propose a connectivity-preserving flocking algorithm for multi-agent systems in which the neighbor set of each agent is determined by the hybrid metric-topological distance so that the interaction topology can be represented as the range-limited Delaunay graph, which combines the properties of the commonly used disk graph and Delaunay graph. As a result, the proposed flocking algorithm has the following advantages over the existing ones. First, range-limited Delaunay graph is sparser than the disk graph so that the information exchange among agents is reduced significantly. Second, some links irrelevant to the connectivity can be dynamically deleted during the evolution of the system. Thus, the proposed flocking algorithm is more flexible than existing algorithms, where links are not allowed to be disconnected once they are created. Finally, the multi-agent system spontaneously generates a regular quasi-lattice formation without imposing the constraint on the ratio of the sensing range of the agent to the desired distance between two adjacent agents. With the interaction topology induced by the hybrid distance, the proposed flocking algorithm can still be implemented in a distributed manner. We prove that the proposed flocking algorithm can steer the multi-agent system to a stable flocking motion, provided the initial interaction topology of multi-agent systems is connected and the hysteresis in link addition is smaller than a derived upper bound. The correctness and effectiveness of the proposed algorithm are verified by extensive numerical simulations, where the flocking algorithms based on the disk and Delaunay graph are compared.

  16. A flocking algorithm for multi-agent systems with connectivity preservation under hybrid metric-topological interactions.

    Directory of Open Access Journals (Sweden)

    Chenlong He

    Full Text Available In this paper, we propose a connectivity-preserving flocking algorithm for multi-agent systems in which the neighbor set of each agent is determined by the hybrid metric-topological distance so that the interaction topology can be represented as the range-limited Delaunay graph, which combines the properties of the commonly used disk graph and Delaunay graph. As a result, the proposed flocking algorithm has the following advantages over the existing ones. First, range-limited Delaunay graph is sparser than the disk graph so that the information exchange among agents is reduced significantly. Second, some links irrelevant to the connectivity can be dynamically deleted during the evolution of the system. Thus, the proposed flocking algorithm is more flexible than existing algorithms, where links are not allowed to be disconnected once they are created. Finally, the multi-agent system spontaneously generates a regular quasi-lattice formation without imposing the constraint on the ratio of the sensing range of the agent to the desired distance between two adjacent agents. With the interaction topology induced by the hybrid distance, the proposed flocking algorithm can still be implemented in a distributed manner. We prove that the proposed flocking algorithm can steer the multi-agent system to a stable flocking motion, provided the initial interaction topology of multi-agent systems is connected and the hysteresis in link addition is smaller than a derived upper bound. The correctness and effectiveness of the proposed algorithm are verified by extensive numerical simulations, where the flocking algorithms based on the disk and Delaunay graph are compared.

  17. Fixed-Wing UAVs Flock Control through Cohesion and Repulsion Behaviours Combined with a Leadership

    Directory of Open Access Journals (Sweden)

    Cezary Kownacki

    2016-02-01

    Full Text Available The aim of this paper is to present a novel approach to swarm control of small fixed-wing UAVs, which combines only two flocking behaviours with a leadership feature. In the presented approach, two fundamental rules of Reynolds flocking are applied, i.e., cohesion and repulsion, as the base of a decentralized control of self-organization of the flock. These rules are combined with a leadership feature, which is responsible for a global behaviour of guidance, as in the case of animals. Such a bio-inspired combination allows the achievement of a coherent collective flight of a flock of fixed-wing UAVs without applying formal behaviours of migration and alignment. This highly simplifies an implementation of the algorithm. The presented results include both numerical simulations and experimental flights, which validate the hardware implementation of the approach.

  18. THE USE OF STABILIZED LIQUIDE CHLORINE DIOXIDE (ClO2 FOR INTERNAL WATER SUPPLY SYSTEM SANITATION OF FARM WITH LAYING FLOCK AFFECTED BY COLISEPTICEMIA

    Directory of Open Access Journals (Sweden)

    Abdulah Gagić

    2014-03-01

    Full Text Available A successful and harmless method for rehabilitation of hygienic status of water and its supply system using a stabilized liquid chlorine dioxide solution on a farm of the laying hens affected by severe colisepticemia is described. Source of infection was drinking water contaminated by slurry from two pig facilities located above the water tank. The contaminated water caused the emergence of biofilm consisting mainly of coliform bacteria on the interior surfaces of the plastic pipes. Through drinking the contaminated water the infection of the laying flocks occurred. With the aim of improving the flocks’ health status, a programme of sanitary treatment of external and internal water supply system and water was created and implemented. In order to prevent biofilm formation and improve sanitation prescribed was the use of stabilized liquid chlorine dioxide (ClO2 in the 4‰ concentration for so-called night "shock" treatments, and 2‰ concentration for prophylactic daily disinfection of drinking water. With the improvement of the flocks’ health status, the "shock" treatments with ClO2 were repeated in the upcoming months. As an add-on therapy, 40 mg per bird of vitamin C through drinking water for three days was prescribed. The use of non-resorptive antibiotics, AD3E vitamins and amino acid supplements was excluded because they had failed to improve the flocks’ health status in the acute phase. Therefore, the sanitation programme based on the use of stabilized liquid ClO2 in the water supply system of the laying flocks affected by severe colisepticemia resulted in radical decrease of mortality during the next three months. Key words: chlorine dioxide, biofilm, sanitation, disinfection, colisepticemia

  19. Keel-bone damage and foot injuries in commercial laying hens in Denmark

    DEFF Research Database (Denmark)

    Riber, Anja Brinch; Hinrichsen, Lena Karina

    2016-01-01

    . There was no difference between barn and organic production systems in the risk of having keel-bone fractures and foot injuries, except that barn hens were more likely to have foot-pad lesions than organic hens(32 weeks: 16.1 vs 3.1%). Hens in multi-tiered systems were more likely to have keel-bone fractures compared...... to hens in single-tiered systems (62 weeks: 11.6 vs 4.9 %). Of the four hybrids, Lohmann Brown Lite had a higher risk of keel-bone fractures, whereas bumble feet were found more frequently in Lohmann LSL. Keel-bone damage and foot injuries are less common in Danish non-cage systems compared to most...

  20. Sleep in the domestic hen (Gallus domesticus).

    Science.gov (United States)

    van Luijtelaar, E L; van der Grinten, C P; Blokhuis, H J; Coenen, A M

    1987-01-01

    Electrophysiological recordings were made of five closely observed hens, all permanently implanted with both EEG and EMG electrodes. Five behavioural postures were distinguished and percentages of wakefulness, sleep and presumably paradoxical sleep (PS) were determined during the third and sixth hour of the dark period. Substantial agreement was generally found between behaviour and sleep with the exception of sitting or standing motionless with at least one eye open. During two thirds of this behavioural posture, the EEG showed large amplitude slow waves undistinguishable from slow wave sleep. Characteristics of PS were determined: periods were short, whereas its percentage increased during the night. Furthermore, EMG atonia was never found. An all night recording was made, and delta activity (2-5 Hz) was filtered and plotted against time for three of the hens. A significant decrease in delta activity across the night was found. Differences and similarities between sleep in hens and in mammals are discussed. Although large similarities exist it is concluded that some properties of birds' sleep make it unique and are a challenge for further study.

  1. Robustness in laying hens

    NARCIS (Netherlands)

    Star, L.

    2008-01-01

    The aim of the project ‘The genetics of robustness in laying hens’ was to investigate nature and regulation of robustness in laying hens under sub-optimal conditions and the possibility to increase robustness by using animal breeding without loss of production. At the start of the project, a robust

  2. Generalised linear mixed models analysis of risk factors for contamination of Danish broiler flocks with Salmonella typhimurium

    DEFF Research Database (Denmark)

    Chriél, Mariann; Stryhn, H.; Dauphin, G.

    1999-01-01

    are the broiler flocks (about 4000 flocks) which are clustered within producers. Broiler flocks with ST-infected parent stocks show increased risk of salmonella infection, and also the hatchery affects the salmonella status significantly. Among the rearing factors, only the use of medicine as well as the time......We present a retrospective observational study of risk factors associated with the occurrence of Salmonella typhimurium (ST) in Danish broiler flocks. The study is based on recordings from 1994 in the ante-mortem database maintained by the Danish Poultry Council. The epidemiological units...

  3. Nutritional quality of eggs from hens fed distillers dried grains with solubles.

    Science.gov (United States)

    Trupia, S; Winkler-Moser, J K; Guney, A C; Beckstead, R; Chen, C-Y O

    2016-11-01

    A feeding trial was conducted with laying hens where either 10% or 20% regular-fat distiller's dried grains with solubles (R-DDGS) or low-fat DDGS (L-DDGS) were incorporated into the feed. Production parameters and the effect of DDGS on egg nutritional quality, focusing on yolk lipids, were evaluated. Neither R-DDGS nor L-DDGS at up to 20% of laying hen feeds had a statistically significant impact on hen weight gain, egg production, feed intake, feed efficiency, egg mass, or egg weight. Specific gravity was slightly lower for eggs from hens fed 10% R-DDGS or 20% L-DDGS. Eggs from layers fed DDGS had enhanced levels of tocopherols, tocotrienols, and xanthophylls in the yolk, as well as also increased yolk yellow and red color. Eggs from L-DDGS diet had higher tocopherol content, but eggs from R-DDGS diets had higher xanthophylls. Fatty acid composition in eggs was slightly altered by DDGS, but the ratio of saturated to unsaturated fatty acids was very similar. Feeding DDGS to layer hens had no effect on lecithin or cholesterol content of the eggs. Thus, inclusion of DDGS in the diet of laying hens resulted in increases of several beneficial lipophilic nutrients in egg yolks with no apparent detrimental effects. © 2016 Poultry Science Association Inc.

  4. Reproductive responses of white leghorn hens to graded concentrations of mercuric chloride

    Science.gov (United States)

    Hill, E.F.; Shaffner, C.S.

    1974-01-01

    White Leghorn hens were maintained on diets containing 0, 4, 12 or 36 p.p.m. Hg as HgCl2 from hatching in an effort to confirm (with a second species) our previously reported effects on Japanese quail reproduction. In the quail study both onset of laying and rate of egg production were accelerated by 16 and 32 p.p.m. Hg as HgCl2, but ferti ity was depressed. After 1 year on diets containing HgCl2 none of the Leghorn hens manifested any observed signs of Hg poisoning. Hens fed 4 or 12 p.p.m. Hg began ovipositing an average of 10 days earlier than the controls (P < 0.05). Young hens (< 9 months old) fed 4 or 12 p.p.m. Hg laid significantly more eggs per hen-day than did either controls or those fed 36 p.p.m. Hg. Beyond 9 months of age there were no perceptible differences in rate of egg production among the treatments. These findings support our quail results. When the hens were inseminated with pooled semen from untreated roosters fertility, embryonic development and hatchability appeared to be unaffected by the treatments. This contrasts with our previous experiment with quail in which both sexes were fed HgCl2.

  5. Does rearing laying hens in aviaries adversely affect long-term welfare following transfer to furnished cages?

    Directory of Open Access Journals (Sweden)

    Fernanda M Tahamtani

    Full Text Available This study tests the hypothesis that hens that are reared in aviaries but produce in furnished cages experience poorer welfare in production than hens reared in caged systems. This hypothesis is based on the suggestion that the spatial restriction associated with the transfer from aviaries to cages results in frustration or stress for the aviary reared birds. To assess the difference in welfare between aviary and cage reared hens in production, non-beak trimmed white leghorn birds from both rearing backgrounds were filmed at a commercial farm that used furnished cage housing. The videos were taken at 19 and 21 weeks of age, following the birds' transition to the production environment at 16 weeks. Videos were analysed in terms of the performance of aversion-related behaviour in undisturbed birds, comfort behaviour in undisturbed birds, and alert behaviour directed to a novel object in the home cage. A decrease in the performance of the former behaviour and increase in the performance of the latter two behaviours indicates improved welfare. The results showed that aviary reared birds performed more alert behaviour near to the object than did cage reared birds at 19 but not at 21 weeks of age (P = 0.03. Blood glucose concentrations did not differ between the treatments (P>0.10. There was a significant difference in mortality between treatments (P = 0.000, with more death in aviary reared birds (5.52% compared to cage birds (2.48%. The higher mortality of aviary-reared birds indicates a negative effect of aviary rearing on bird welfare, whereas the higher duration of alert behavior suggests a positive effect of aviary rearing.

  6. Flocking multiple microparticles with automatically controlled optical tweezers: solutions and experiments.

    Science.gov (United States)

    Chen, Haoyao; Wang, Can; Lou, Yunjiang

    2013-06-01

    This paper presents an efficient approach to achieve microparticles flocking with robotics and optical tweezers technologies. All particles trapped by optical tweezers can be automatically moved toward a predefined region without collision. The main contribution of this paper lies in the proposal of several solutions to the flocking manipulation of microparticles in microenvironments. First, a simple flocking controller is proposed to generate the desired positions and velocities for particles' movement. Second, a velocity saturation method is implemented to prevent the desired velocities from exceeding a safe limit. Third, a two-layer control architecture is proposed for the motion control of optical tweezers. This architecture can help make many robotic manipulations achievable under microenvironments. The proposed approach with these solutions can be applied to many bioapplications especially in cell engineering and biomedicine. Experiments on yeast cells with a robot-tweezers system are finally performed to verify the effectiveness of the proposed approach.

  7. Novel Polymorphisms of Adrenergic, Alpha-1B-, Receptor and Peroxisome Proliferator-activated Receptor Gamma, Coactivator 1 Beta Genes and Their Association with Egg Production Traits in Local Chinese Dagu Hens

    Directory of Open Access Journals (Sweden)

    F. Mu

    2016-09-01

    Full Text Available Adrenergic, alpha-1B-, receptor (ADRA1B and peroxisome proliferator-activated receptor gamma, coactivator 1 beta (PPARGC1B genes are involved in regulation of hen ovarian development. In this study, these two genes were investigated as possible molecular markers associated with hen-housed egg production, egg weight (EW and body weight in Chinese Dagu hens. Samples were analyzed using the polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP technique, followed by sequencing analysis. Two novel single nucleotide polymorphisms (SNPs were identified within the candidate genes. Among them, an A/G transition at base position 1915 in exon 2 of ADRA1B gene and a T/C mutation at base position 6146 in the 3′-untranslated region (UTR of PPARGC1B gene were found to be polymorphic and named SNP A1915G and T6146C, respectively. The SNP A1915G (ADRA1B leads to a non-synonymous substitution (aspartic acid 489-to-glycine. The 360 birds from the Dagu population were divided into genotypes AA and AG, allele A was found to be present at a higher frequency. Furthermore, the AG genotype correlated with significantly higher hen-housed egg production (HHEP at 30, 43, 57, and 66 wks of age and with a higher EW at 30 and 43 wks (p<0.05. For the SNP T6146C (PPARGC1B, the hens were typed into TT and TC genotypes, with the T allele shown to be dominant. The TC genotype was also markedly correlated with higher HHEP at 57 and 66 wks of age and EW at 30 and 43 wks (p<0.05. Moreover, four haplotypes were reconstructed based on these two SNPs, with the AGTC haplotype found to be associated with the highest HHEP at 30 to 66 wks of age and with higher EW at 30 and 43 wks (p<0.05. Collectively, the two SNPs identified in this study might be used as potential genetic molecular markers favorable in the improvement of egg productivity in chicken breeding.

  8. Both feather peckers and victims are more asymmetrical than control hens

    DEFF Research Database (Denmark)

    Machado Tahamtani, Fernanda; Forkman, Björn; Hinrichsen, Lena Karina

    2017-01-01

    Feather pecking is the major welfare issue facing the egg farming industry worldwide. Previous research has found a relationship between cannibalistic behaviour, fluctuating asymmetry of bilateral traits (FA) and body weight in laying hens. As cannibalism is linked to severe feather pecking......, it could be suggested that a relationship between feather pecking, FA and body weight also exists. The purpose of this study was to analyse the association between feather pecking behaviour and a) FA, b) body weight and c) comb size in laying hens. Sixty-four laying hens were categorised as feather peckers...

  9. Reflective properties of domestic fowl (Gallus g. domesticus), the fabric of their housing and the characteristics of the light environment in environmentally controlled poultry houses.

    Science.gov (United States)

    Prescott, N B; Wathes, C M

    1999-05-01

    1. The light intensity and spectral power distribution in 3 broiler and 6 layer houses were sampled and converted to a measure which takes account of the domestic fowl's spectral sensitivity (termed lux corrected). Light intensity was highly variable around the layer houses (mean 33.2, s.d. 37.7 lux (corrected)) and to a lesser extent in the broiler houses (mean 5.2, s.d. 2.2 lux (corrected)). The mean intensities were also very much lower than on a sunny, June day at midday at Silsoe (42,937 lux (corrected)) and of different power distributions. 2. The reflectivity of the plumage of 15 traditional breeds of domestic fowl was surveyed. Most feathers showed a characteristic pattern of reflectivity, increasing either side of a wavelength of lambda = 400 nm. In 13 breeds the tail and wing feathers were darker than the breast and back feathers. Reflectivity at lambda = 700 nm was a good predictor of reflectivity at lambda = 320 nm. Food, bedding, wood and skin all had similar reflectivities to feathers. Metal, plastic and rubber all had more constant reflectivities across the spectrum. 3. The reflectivities of the fresh, feathered carcases of 3 male broilers (Cobb) and 3 layer hens (ISA Brown) were measured. There were small changes in hue and saturation within and between individual carcases, even for the apparently white broiler chickens. 4. Photographs were taken, with and without a UV(A)-only pass filter, of a broiler cock (Cobb), layer hen (ISA Brown) and cock jungle fowl. No additional patternation was evident in the UV(A)-only photographs and the jungle fowl lost most of its ornamentation. The texture of bare skin was enhanced in the UV(A)-only photographs. 5. The implications of these results for poultry behaviour are discussed.

  10. Performance, egg quality, and liver lipid reserves of free-range laying hens naturally infected with Ascaridia galli.

    Science.gov (United States)

    Sharma, N; Hunt, P W; Hine, B C; Sharma, N K; Chung, A; Swick, R A; Ruhnke, I

    2018-03-16

    A study was conducted to determine the performance, egg quality, and liver lipid reserves of laying hens exposed to ranges contaminated with Ascaridia galli. Sixteen-week-old Lohmann Brown laying hens (n = 200) were divided into 4 treatments with 5 replicates containing 10 hens per pen. Hens of treatment 1 [negative control (NC)] ranged on a decontaminated area, and hens of treatments 2 (low infection) and 3 (medium infection) ranged on areas previously contaminated by hens artificially infected with 250 and 1,000 embryonated A. galli eggs, respectively. The hens of treatment 4 [positive control (PC)] ranged on areas previously contaminated by hens artificially infected with 2,500 embryonated A. galli eggs, and in addition these hens were orally inoculated with 1,000 embryonated eggs. Results indicated that hens of the medium infection group had a higher number of intestinal A. galli worms and A. galli eggs in the coprodeum excreta (43.9 ± 4.0 and 3,437 ± 459 eggs/g) compared to hens of the low infection group (23.8 ± 4.0 and 1,820 ± 450 eggs/g) (P  0.05). Egg production, egg mass, feed intake, and feed conversion ratio (FCR) were not affected by A. galli infection (P > 0.05). Egg quality parameters (egg weight, shell reflectivity, shell weight, shell thickness, shell percentage, shell breaking strength, deformation, albumen height, Haugh unit, and yolk score) were not affected by A. galli infection (P > 0.05). Highly infected hens had lower liver lipid content (2.72 ± 0.51 g) compared to uninfected hens (4.46 ± 0.58 g, P ranges contaminated with A. galli resulted in infection of the ranging hens, but this did not affect egg production or egg quality. Infection with A. galli lowered the liver lipid reserves of the host significantly, suggesting infected hens use more energy reserves for maintenance and production.

  11. Haematophagus Mites in Poultry Farms of Iran

    Directory of Open Access Journals (Sweden)

    S Rahbari

    2009-12-01

    Full Text Available Background: Blood sucking mites are important avian ectoparasites which being found on bird species worldwide. Their presence are problematic for the producers either through potential direct effects on weight gain, egg produc­tion, sperm production in roosters or as nuisance pests on worker handle hens and eggs. The aim of this study was pointing out of the status of haematophagus mites."nMethods: Eight caged layer and four breeder flocks were visited, monitoring for the presence of chicken mites per­formed by removing and examining debris from poultry house, infested nesting material collected into zip lock plas­tic bags and at least 20 birds were also randomly selected to examine the presence of chicken mites. Mites obtained from each population were mounted in Hoyer,s medium on microscope slides and identified. All eight caged layer and four breeder flocks were inspected, which were infested with chicken blood feeding mites."nResults: Massive infestations of Dermanyssus gallinae were common with huge numbers of parasites on birds, cages and the conveyor belts for egg. Only one farm from Mazandaran Province was infested to Ornithonyssus bursa."nConclusion: Dermanyssus gallinae was the most prevalent blood feeder mite in the breeder and caged layer flocks in Iran, while O. bursa was reported as a first record, which found only in a breeder flock in Mazanderan Province. It seems that its presence is limited into the area which affected by both warm and humid environmental conditions.  Keywords: Dermanyssus gallinae, Ornithonyssus bursa, Poultry, Iran

  12. Flocking Control of Multiple Mobile Agents with the Rules of Avoiding Collision

    Directory of Open Access Journals (Sweden)

    Hongtao Zhou

    2015-01-01

    Full Text Available This paper investigates the flocking and the coordinative control problems of multiple mobile agents with the rules of avoiding collision. We propose a set of control laws using hysteresis in adding new links and applying new potential function to guarantee that the fragmentation of the network can be avoided, under which all agents approach a common velocity vector, and asymptotically converge to a fixed value of interagent distances and collisions between agents can be avoided throughout the motion. Furthermore, we extend the flocking algorithm to solve the flocking situation of the group with a virtual leader agent. The laws can make all agents asymptotically approach the virtual leader and collisions can be avoided between agents in the motion evolution. Finally, some numerical simulations are showed to illustrate the theoretical results.

  13. Dynamics of CMY-2 producing E. coli in a broiler parent flock.

    Science.gov (United States)

    Dame-Korevaar, Anita; Fischer, Egil A J; Stegeman, Arjan; Mevius, Dik; van Essen-Zandbergen, Alieda; Velkers, Francisca; van der Goot, Jeanet

    2017-05-01

    Extended-spectrum β-lactamase and plasmid mediated AmpC β-lactamase (ESBL/pAmpC) producing bacteria are resistant to Extended Spectrum Cephalosporins (ESC), and are present in all levels of the broiler production chain. We determined the prevalence, concentration, and persistence of ESBL/pAmpC-Escherichia coli in a broiler parent flock during the rearing and laying period. One-day old chickens were housed in four separate pens. Until week 33 no antibiotics or coccidiostatics were used. During rearing 57 chickens in each pen (n=228), and in the laying period two groups of 33 chickens were individually sampled (n=66). Environmental samples were taken from week 16 onwards. ESBL/pAmpC-E. coli presence was determined by selective culturing. In the samples of week 16-19 the concentration of ESBL/pAmpC-E. coli was determined. All ESC-resistant isolates found were positive for pAmpC gene bla CMY-2 located on IncA/C plasmids, in several E. coli MLST types. CMY-2-E. coli prevalence decreased from 91% (95%CI 86-94%) at day 7 (week 1) to 0% (95%CI 0-5%) in week 21. However, CMY-2-E. coli remained present in the environmental samples during the whole study. CMY-2-E. coli concentration varied between detection limit (E. coli in this broiler parent flock in absence of antibiotics suggests a selective disadvantage of bla CMY-2 on IncA/C plasmids on animal level. The underlying mechanism should be studied further as this may provide new insights on how to reduce ESBL/pAmpC prevalence and transmission in the broiler production chain. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Influence of in-house composting of reused litter on litter quality, ammonia volatilisation and incidence of broiler foot pad dermatitis.

    Science.gov (United States)

    Martins, R S; Hötzel, M J; Poletto, R

    2013-01-01

    1. The objectives of this study were to evaluate the residual effects of two windrow composting methods for reused litter on its quality (pH, moisture, ammonia), ammonia (NH3) volatilisation and the prevalence (scores 0-4) of foot pad dermatitis (FPD) and hock burn (HB) on d 1, 7, 14 and 21 of age in broilers. Litter was allowed to compost for 8 d within a 14-d interval between flocks. 2. The composting methods studied were with or without a PVC plastic sheet. The same procedures were applied for three consecutive flocks, with litter initially having been used for 12 flocks. Data were analysed with a mixed model of repeated measures of day, with main effects and interactions of day, composting method, litter age (block) and house nested within method. 3. At d 1, litter NH3 and NH3 volatilisation were higher in the covered litter method. Litter moisture increased to 45.3% as broilers aged. The incidence of FPD also increased with age. No signs of HB were found in any bird throughout the trials. 4. There was no effect of litter composting methods on the prevalence of FPD or body weight at any age. 5. Litter moisture should be controlled to avoid NH3 volatilisation reaching critical levels. Windrow composting of litter with a PVC plastic sheet may not be required when considering the broiler housing environment.

  15. Birds, magnets, soap, and sandblasting: surprising connections in the theory of incompressible flocks

    Science.gov (United States)

    Toner, John

    In this talk I'll describe the hydrodynamic theory of the motion of incompressible flocks: that is, collections of self-propelled entities (birds\\x9D) that are packed so tightly together that their density cannot change as they move. In two dimensions, this problem can be mapped onto an equilibrium magnet with a peculiar constraint. This problem, in turn, can be shown to be equivalent to a 2d smectic (soap\\x9D), with the flow lines of the flock playing the role of the smectic layers. Finally, this smectic problem can be mapped onto the 1+1 dimensional KPZ equation, which describes the growth or corrosion (sandblasting\\x9D) of a one dimensional interface. The scaling properties of this last system, which have been known exactly for a long time, can thereby be used to determine those of incompressible 2d flocks. One important implication of the resulting scaling laws is that such flocks can exhibit long-ranged order in two dimensions, unlike their equilibrium counterparts.

  16. On the duality between interaction responses and mutual positions in flocking and schooling.

    Science.gov (United States)

    Perna, Andrea; Grégoire, Guillaume; Mann, Richard P

    2014-01-01

    Recent research in animal behaviour has contributed to determine how alignment, turning responses, and changes of speed mediate flocking and schooling interactions in different animal species. Here, we propose a complementary approach to the analysis of flocking phenomena, based on the idea that animals occupy preferential, anysotropic positions with respect to their neighbours, and devote a large amount of their interaction responses to maintaining their mutual positions. We test our approach by deriving the apparent alignment and attraction responses from simulated trajectories of animals moving side by side, or one in front of the other. We show that the anisotropic positioning of individuals, in combination with noise, is sufficient to reproduce several aspects of the movement responses observed in real animal groups. This anisotropy at the level of interactions should be considered explicitly in future models of flocking and schooling. By making a distinction between interaction responses involved in maintaining a preferred flock configuration, and interaction responses directed at changing it, our work provides a frame to discriminate movement interactions that signal directional conflict from interactions underlying consensual group motion.

  17. Effect of superdosing phytase on productive performance and egg quality in laying hens

    Directory of Open Access Journals (Sweden)

    Jong Hyuk Kim

    2017-07-01

    Full Text Available Objective An experiment was conducted to determine the effect of superdosing phytase on productive performance and egg quality in laying hens. Methods A total of 200 42-wk-old Hy-Line Brown laying hens were allotted into 1 of 5 dietary treatments with 5 replicates consisting of 8 hens per replicate. The positive control (PC and negative control diets (NC were prepared based on the recommended P levels in layer diets. Supplemental phytase was added to the negative control diet at 10,000 (SD10, 20,000 (SD20, or 30,000 (SD30 fytase units (FTU/kg. Productive performance was summarized for 6 weeks from 42 weeks to 47 weeks of age. Egg quality was assessed from 4 eggs per replicate randomly collected at the conclusion of the experiment. Results The SD20 treatment had greater (p<0.05 hen-day egg production than PC, NC, and SD10 treatment groups. There was no difference in hen-day egg production between SD20 and SD30 treatment groups. However, SD30 treatment had greater (p<0.05 hen-day egg production than PC treatment, but showed no difference in hen-day egg production as compared to NC and SD10 treatment groups. However, egg weight, egg mass, feed intake, and feed conversion ratio were not affected by dietary treatments. Egg quality including eggshell strength, eggshell color, egg yolk color, and haugh unit was not influenced by dietary treatments. Conclusion Superdosing level of 20,000 FTU/kg phytase in diets has a positive effect on egg production rate, but no beneficial effect on egg quality in laying hens.

  18. Flocking-based Document Clustering on the Graphics Processing Unit

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Xiaohui [ORNL; Potok, Thomas E [ORNL; Patton, Robert M [ORNL; ST Charles, Jesse Lee [ORNL

    2008-01-01

    Abstract?Analyzing and grouping documents by content is a complex problem. One explored method of solving this problem borrows from nature, imitating the flocking behavior of birds. Each bird represents a single document and flies toward other documents that are similar to it. One limitation of this method of document clustering is its complexity O(n2). As the number of documents grows, it becomes increasingly difficult to receive results in a reasonable amount of time. However, flocking behavior, along with most naturally inspired algorithms such as ant colony optimization and particle swarm optimization, are highly parallel and have found increased performance on expensive cluster computers. In the last few years, the graphics processing unit (GPU) has received attention for its ability to solve highly-parallel and semi-parallel problems much faster than the traditional sequential processor. Some applications see a huge increase in performance on this new platform. The cost of these high-performance devices is also marginal when compared with the price of cluster machines. In this paper, we have conducted research to exploit this architecture and apply its strengths to the document flocking problem. Our results highlight the potential benefit the GPU brings to all naturally inspired algorithms. Using the CUDA platform from NIVIDA? we developed a document flocking implementation to be run on the NIVIDA?GEFORCE 8800. Additionally, we developed a similar but sequential implementation of the same algorithm to be run on a desktop CPU. We tested the performance of each on groups of news articles ranging in size from 200 to 3000 documents. The results of these tests were very significant. Performance gains ranged from three to nearly five times improvement of the GPU over the CPU implementation. This dramatic improvement in runtime makes the GPU a potentially revolutionary platform for document clustering algorithms.

  19. A Distributed Agent Implementation of Multiple Species Flocking Model for Document Partitioning Clustering

    Energy Technology Data Exchange (ETDEWEB)

    Cui, Xiaohui [ORNL; Potok, Thomas E [ORNL

    2006-01-01

    The Flocking model, first proposed by Craig Reynolds, is one of the first bio-inspired computational collective behavior models that has many popular applications, such as animation. Our early research has resulted in a flock clustering algorithm that can achieve better performance than the Kmeans or the Ant clustering algorithms for data clustering. This algorithm generates a clustering of a given set of data through the embedding of the highdimensional data items on a two-dimensional grid for efficient clustering result retrieval and visualization. In this paper, we propose a bio-inspired clustering model, the Multiple Species Flocking clustering model (MSF), and present a distributed multi-agent MSF approach for document clustering.

  20. Speed Determines Leadership and Leadership Determines Learning during Pigeon Flocking.

    Science.gov (United States)

    Pettit, Benjamin; Ákos, Zsuzsa; Vicsek, Tamás; Biro, Dora

    2015-12-07

    A key question in collective behavior is how individual differences structure animal groups, affect the flow of information, and give some group members greater weight in decisions. Depending on what factors contribute to leadership, despotic decisions could either improve decision accuracy or interfere with swarm intelligence. The mechanisms behind leadership are therefore important for understanding its functional significance. In this study, we compared pigeons' relative influence over flock direction to their solo flight characteristics. A pigeon's degree of leadership was predicted by its ground speeds from earlier solo flights, but not by the straightness of its previous solo route. By testing the birds individually after a series of flock flights, we found that leaders had learned straighter homing routes than followers, as we would expect if followers attended less to the landscape and more to conspecifics. We repeated the experiment from three homing sites using multiple independent flocks and found individual consistency in leadership and speed. Our results suggest that the leadership hierarchies observed in previous studies could arise from differences in the birds' typical speeds. Rather than reflecting social preferences that optimize group decisions, leadership may be an inevitable consequence of heterogeneous flight characteristics within self-organized flocks. We also found that leaders learn faster and become better navigators, even if leadership is not initially due to navigational ability. The roles that individuals fall into during collective motion might therefore have far-reaching effects on how they learn about the environment and use social information. Copyright © 2015 Elsevier Ltd. All rights reserved.

  1. Utilization of sunflower seed in laying hen rations

    Directory of Open Access Journals (Sweden)

    Tsuzuki ET

    2003-01-01

    Full Text Available The objective of this trial was to evaluate the effect of sunflower seed inclusion (0, 1.4, 2.8, 4.2 and 5.6% in a laying hen diet containing corn, soybean meal, wheat meal and soybean oil as main ingredients on performance and egg quality. The evaluated variables were daily feed intake, average egg weight, feed conversion (kg.kg-1 and kg.dz-1, eggshell percentage, yolk color and Haugh unit. One hundred and sixty 25 week-old Lohmann laying hens were used in a completely randomized design with five treatments and four replications of eight birds per experimental unit. Four periods of 28 days were evaluated during 112 days. The inclusion of sunflower seed in the diet had no effect on production parameters during the experimental period. Thus, can be concluded that sunflower seed might be used at concentrations up to 5.6% in laying hen diets without affecting performance and egg quality.

  2. Effects of nanocalcium carbonate on egg production performance and plasma calcium of laying hens.

    Science.gov (United States)

    Ganjigohari, S; Ziaei, N; Ramzani Ghara, A; Tasharrofi, S

    2018-02-01

    This experiment was conducted to evaluate the effects of nanocalcium carbonate (NCC) instead of calcium carbonate (CC) on egg production, egg weight, egg mass, FCR, blood calcium and egg quality characteristics in laying hens. A total of 120 laying hens were used in a 10-weeks trial, from week 23 to 33 of age. Laying hens were randomly assigned to six treatments with four replications, five hens each. The experimental treatments involved replacing 50% of the CC in the diet by decreasing amounts of NCC and were T1 Basal diet (BD) with 8.06% CC; T2 (6.045% of CC as a negative control); T3 (4.03% of CC replaced by 2.015% NCC); T4 (4.03% of CC replaced by 1.01% NCC); T5 (4.03% of CC replaced by 0.252% NCC) and T6 (4.03 of CC replaced with 0.126%NCC).Egg weight was unaffected by dietary treatments (p > .05). However, the egg production percentage and egg mass in T6 were less than that of other treatments (p hens in the control group had the best average feed conversion ratio (p hens' blood was recorded for birds fed T6 (p hens. © 2017 Blackwell Verlag GmbH.

  3. Effect of thermal processing on retinol levels of free-range and caged hen eggs.

    Science.gov (United States)

    Ramalho, Héryka M M; Santos, Videanny V A; Medeiros, Vanessa P Q; Silva, Keith H D; Dimenstein, Roberto

    2006-01-01

    Purpose Eggs are a food item of high nutritional value, a source of vitamin A and readily accessible to the general population. Methods This paper analysed the effect of cooking on the retinol levels of free-range and caged hen eggs, using high performance liquid chromatography (HPLC). The retinol levels of hen and quail eggs were also compared. Results The raw egg yolk retinol concentrations of free-range and caged hen eggs were 476.53+/-39.44 and 474.93+/-41.10 microg/100 g and cooked egg yolk concentrations were 393.53+/-24.74 and 379.01+/-30.78 microg/100 g, respectively; quail egg concentration was 636.56+/-32.71 microg retinol/100 g. No significant difference was found between the retinol of free-range and caged hen egg yolks; however, cooking diminished retinol levels, causing a loss of 17 and 20% in the free-range and caged hen egg yolks, respectively. Quail egg retinol concentration was significantly higher than that of the hens. Conclusion The retinol found in 100 g of hen and quail egg yolks could supply around 42 and 70.7% of the vitamin A requirements of an adult man, and is accordingly considered an excellent source of this vitamin.

  4. Differential abundance of egg white proteins in laying hens treated with corticosterone.

    Science.gov (United States)

    Kim, Jimin; Choi, Yang-Ho

    2014-12-24

    Stressful environments can affect not only egg production and quality but also gene and protein abundance in the ovary and oviduct in laying hens. The oviductal magnum of laying hens is the organ responsible for the synthesis and secretion of egg white proteins. The objective of this study was to investigate the effects of dietary corticosterone as a stress model on the abundance of proteins in the egg white and of mRNA and proteins in the magnum in laying hens. After a 14-day acclimation, 40 laying hens were divided into two groups which were provided for the next 14 days with either control (Control) or corticosterone (Stress) diet containing at 30 mg/kg. Corticosterone treatment resulted in increased feed intake (P ≤ 0.05) and decreased egg production. Two-dimensional electrophoresis (2DE) with MALDI-TOF/TOF MS/MS using eggs obtained on days 0 and 5 revealed differential abundance of egg white proteins by Stress: transiently expressed in neural precursors (TENP), hemopexin (HPX), IgY-Fcυ3-4, and extracellular fatty acid-binding protein (Ex-FABP) were decreased while ovoinhibitor and ovalbumin-related protein X (OVAX) were increased on days 5 vs 0 (P ≤ 0.05). Expression of mRNAs and proteins was also significantly modulated in the magnum of hens in Stress on day 14 (P ≤ 0.05). In conclusion, the current study provides the first evidence showing that dietary corticosterone modulates protein abundance in the egg white in laying hens, and it suggests that environmental stress can differentially modify expression of egg white proteins in laying hens.

  5. Sand intake by laying hens and its effect on egg production parameters.

    Science.gov (United States)

    van der Meulen, J; Kwakernaak, C; Kan, C A

    2008-08-01

    Soil intake may be the most prominent source of environmental contaminants for free range and organic hens, but there are no quantitative data concerning soil intake by domestic hens. Consumption of soil of 14-32 g a day can be estimated from literature, but such a dilution of nutrient intake seems incompatible with high productivity. In this study laying hens were fed pelleted diets with 0%, 10%, 20%, 25% and 30% of sand addition to determine its effect on productivity. Feed intake, feed and nutrient (feed minus sand) conversion ratio, egg production, egg weight and body weight gain were measured over a 4-week period. Acid insoluble ash concentration in the faeces was measured to determine the accuracy of estimating the soil ingestion by the soil-ingestion equation for wildlife as a way to determine soil ingestion of free range and organic hens under practical circumstances. The hens were able to compensate the dilution of the diet with 20%, 25% and 30% of sand by increasing their feed intake. Feed intake increased significantly and feed to egg conversion ratio decreased significantly with increasing sand levels in the diet. The nutrient to egg conversion ratio of the diet without sand tended to be worse than for the diets with sand, presumably due to the total absence of coarse material in the diet. There were no differences in egg production and egg weight between hens fed the different diets but body weight gain was significantly lower for the hens fed the diets with 20%, 25% and 30% of sand. Estimation of sand ingestion was done by the soil-ingestion equation for wildlife. Provided that the actual dry matter digestibility coefficient of the nutrient part of the diet is taken into account, estimating the soil ingestion according to the soil-ingestion equation for wildlife seems an appropriate way to determine soil ingestion for free range and organic hens under practical circumstances.

  6. Electrostatic flocking of chitosan fibres leads to highly porous, elastic and fully biodegradable anisotropic scaffolds.

    Science.gov (United States)

    Gossla, Elke; Tonndorf, Robert; Bernhardt, Anne; Kirsten, Martin; Hund, Rolf-Dieter; Aibibu, Dilibar; Cherif, Chokri; Gelinsky, Michael

    2016-10-15

    Electrostatic flocking - a common textile technology which has been applied in industry for decades - is based on the deposition of short polymer fibres in a parallel aligned fashion on flat or curved substrates, covered with a layer of a suitable adhesive. Due to their highly anisotropic properties the resulting velvet-like structures can be utilised as scaffolds for tissue engineering applications in which the space between the fibres can be defined as pores. In the present study we have developed a fully resorbable compression elastic flock scaffold from a single material system based on chitosan. The fibres and the resulting scaffolds were analysed concerning their structural and mechanical properties and the biocompatibility was tested in vitro. The tensile strength and Young's modulus of the chitosan fibres were analysed as a function of the applied sterilisation technique (ethanol, supercritical carbon dioxide, γ-irradiation and autoclaving). All sterilisation methods decreased the Young's modulus (from 14GPa to 6-12GPa). The tensile strength was decreased after all treatments - except after the autoclaving of chitosan fibres submerged in water. Compressive strength of the highly porous flock scaffolds was 18±6kPa with a elastic modulus in the range of 50-100kPa. The flocked scaffolds did not show any cytotoxic effect during indirect or direct culture of human mesenchymal stem cells or the sarcoma osteogenic cell line Saos-2. Furthermore cell adhesion and proliferation of both cell types could be observed. This is the first demonstration of a fully biodegradable scaffold manufactured by electrostatic flocking. Most tissues possess anisotropic fibrous structures. In contrast, most of the commonly used scaffolds have an isotropic morphology. By utilising the textile technology of electrostatic flocking, highly porous and clearly anisotropic scaffolds can be manufactured. Flocking leads to parallel aligned short fibres, glued on the surface of a substrate

  7. Drug use and antimicrobial resistance among Escherichia coli and Enterococcus spp. isolates from chicken and turkey flocks slaughtered in Quebec, Canada.

    Science.gov (United States)

    Boulianne, Martine; Arsenault, Julie; Daignault, Danielle; Archambault, Marie; Letellier, Ann; Dutil, Lucie

    2016-01-01

    An observational study was conducted of chicken and turkey flocks slaughtered at federal processing plants in the province of Quebec, Canada. The objectives were to estimate prevalence of drug use at hatchery and on farm and to identify antimicrobial resistance (AMR) in cecal Escherichia coli and Enterococcus spp. isolates and factors associated with AMR. Eighty-two chicken flocks and 59 turkey flocks were sampled. At the hatchery, the most used antimicrobial was ceftiofur in chickens (76% of flocks) and spectinomycin in turkeys (42% of flocks). Virginiamycin was the antimicrobial most frequently added to the feed in both chicken and turkey flocks. At least 1 E. coli isolate resistant to third-generation cephalosporins was present in all chicken flocks and in a third of turkey flocks. Resistance to tetracycline, streptomycin, and sulfisoxazole was detected in > 90% of flocks for E. coli isolates. Antimicrobial resistance (AMR) was observed to bacitracin, erythromycin, lincomycin, quinupristin-dalfopristin, and tetracycline in both chicken and turkey flocks for Enterococcus spp. isolates. No resistance to vancomycin was observed. The use of ceftiofur at hatchery was significantly associated with the proportion of ceftiofur-resistant E. coli isolates in chicken flocks. In turkey flocks, ceftiofur resistance was more frequent when turkeys were placed on litter previously used by chickens. Associations between drug use and resistance were observed with tetracycline (turkey) in E. coli isolates and with bacitracin (chicken and turkey), gentamicin (turkey), and tylosin (chicken) in Enterococcus spp. isolates. Further studies are needed to provide producers and veterinarians with alternative management practices and tools in order to reduce the use of antimicrobial feed additives in poultry.

  8. QUALITY ASSESSMENT OF EGGS BROWN EGG LAYER HENS CREATION IN TWO SYSTEMS (CAGE AND NEST BED

    Directory of Open Access Journals (Sweden)

    J. Paula

    2015-02-01

    Full Text Available The research objective was to evaluate the effects on the eggs quality in two farming systems (bed + nest and cages for the laying hens brown-egg pullets were used 132 eggs, with six replicates for each treatment and 11 eggs each repetition, picked randomly from sheds both with 2000 DeKalb strain of laying hens housed in two sheds Brown, to create a nest bed + tubular feeders, the other one in cage system, all birds at approximately thirty weeks of age, which evaluated the following variables: weight of whole egg, egg weight without shell, albumen weight, yolk weight, yolk and albumen percentages, weight and thickness, color gem, the albumen pH and yolk, egg and classification according to RIISPOA. All collected data were analyzed by the statistical program SISVAR (2000 by Tukey test at 5% of probability. There were significant differences in the treatments studied in relation to the weight of whole egg, shelled egg weight, albumen%, skin thickness and coloration of the yolk, these results more significant to the breeding system in cages. However it can be concluded that in both systems when properly designed and managed can achieve good results and production performance of birds.

  9. Food restriction but not fish oil increases fertility in hens: role of RARRES2?

    Science.gov (United States)

    Mellouk, Namya; Ramé, Christelle; Delaveau, Joël; Rat, Christophe; Marchand, Maxime; Mercerand, Frédéric; Travel, Angélique; Brionne, Aurélien; Chartrin, Pascal; Ma, Linlin; Froment, Pascal; Dupont, Joëlle

    2018-04-01

    Overfed hens selected for their rapid growth become fatter and develop reproductive disorders. Herein, we aimed to demonstrate that food restriction leading to a weight reduction and/or a supplementation with fish oil may be effective in preventing reproductive disorders through the regulation of adipokine expression in broiler hens. This study included four groups of food restricted (Rt) or ad libitum hens (Ad, feeding at a rate 1.7 times greater than Rt hens) supplemented or unsupplemented with fish oil (1%). The Rt diet significantly increased plasma chemerin (RARRES2) levels during the laying period, delayed sexual maturity by one week and improved egg quality and fertility. These effects were associated with higher progesterone production in response to IGF1 (or LH) in cultured granulosa cells and in vivo egg yolk, as compared with Ad hens. Fish oil supplementation had similar effects to the Rt diet on progesterone ( P  food restriction but not fish oil supplementation improved fertility, and this was associated with variations in RARRES2 plasma and ovarian expression in hens. © 2018 Society for Reproduction and Fertility.

  10. The value of feed consumption data for breeding in laying hens

    NARCIS (Netherlands)

    Luiting, P.

    1991-01-01

    The results of statistical and experimental analyses of residual feed consumption (RFC) in White Leghorn laying hens are presented. RFC is defined as the difference between the observed feed consumption of a hen and its feed consumption predicted from its egg mass production, body weight

  11. Effect of heat stress on the gene expression of ion transporters/channels in the uterus of laying hens during eggshell formation.

    Science.gov (United States)

    Bahadoran, Shahab; Dehghani Samani, Amir; Hassanpour, Hossein

    2018-01-01

    Heat stress is a problem in laying hens as it decreases egg quality by decreasing eggshell mineralization. Heat stress alters gene expression, hence our aim was to investigate effects of heat stress on gene expression of ion transport elements involving in uterine mineralization (TRPV6, CALB1, ITPR3, SCNN1G, SLC4A4, KCNJ15, SLC4A9, and CLCN2) by real time quantitative PCR. Forty 23-week-old White Leghorn laying hens were housed in two rooms. The control group (n = 20) was maintained at 21-23 °C, and the heat stress group (n = 20) was exposed to 36-38 °C for 8 weeks. All parameters of egg quality including egg weight, surface area, volume, and eggshell weight, thickness, ash weight, and calcium content were decreased in the heat stress group compared to the control group (by 26.9%, 32.7%, 44.1%, 38.4%, 31.7%, 39.4%, and 11.1%, respectively). Total plasma calcium was decreased by 13.4%. Levels of ITPR3, SLC4A4, and SLC4A9 transcripts in the uterine lining were decreased in the heat stress group compared to the control group (by 61.4%, 66.1%, and 66.1%, respectively). CALB1 transcript level was increased (by 34.2 fold) in the heat stress group of hens compared to controls. TRPV6, SCNN1G, KCNJ15, and CLCN2 transcript levels did not significantly differ between control and heat stress groups of laying hens. It is concluded that the down-expression of ITPR3, SLC4A4, and SLC4A9 genes may impair transportation of Cl - , HCO 3 - , and Na + in eggshell mineralization during heat stress. Increased CALB1 gene expression may increase resistance of uterine cells to detrimental effects of heat stress.

  12. Flocking at a distance in active granular matter

    Science.gov (United States)

    Soni, Harsh; Kumar, Nitin; Ramaswamy, Sriram; Sood, Ajay

    2014-03-01

    Flocking, the self-organised motion of vast numbers of living creatures in a single direction, relies on organisms sensing each other's presence, orientation and direction of movement. We have attempted to emulate these properties in experiments of fore-aft asymmetric particles energised by a vertically vibrated horizontal surface, and validate and extend our results using computer simulations and a simple hydrodynamic theory. In these studies the asymmetric rods communicate their orientation and directed motion over several rod lengths through a medium of spherical beads. This results in a phase transition from an isotropic state to a coherently moving flock at exceptionally low rod concentrations, an observation reinforced by large-scale numerical simulations. Our findings include a phase diagram in the plane of rod and bead concentrations, power-law spatial correlations upon approaching the phase boundary, and insights into the underlying mechanisms.

  13. Long term dynamics of dermanyssus gallinae in relation to mite control measures in aviary systems for layers.

    Science.gov (United States)

    Nordenfors, H; Höglund, J

    2000-12-01

    1. The dynamics of the poultry red mite, Dermanyssus gallinae, in aviary systems for layers were studied in an empirical study in Sweden between 1994 and 1997. Fluctuations were monitored with mite traps at monthly intervals during 3 laying cycles at each of 2 commercial poultry farms. 2. When mites were first detected in the system it then took about 5 months for the populations to reach equilibrium levels around which they fluctuated. Within flocks when the population growth was unaffected by temporary control activities, it was demonstrated that the mite populations were significantly denser in summer than in winter. 3. Current control methods had limited effects as mite populations were only temporarily suppressed. One exception was the control achieved with permethrin impregnated plastic strips, which reduced the population at equilibrium level to approximately 22%, compared with the previous flock. 4. The distribution of mites was patchy horizontally, along the aviary system, at low burden wlhereas it became more evenly dispersed at equilibrium. 5. Significant differences in vertical mite distributions that correlated with the hybrids used and their rearing conditions were also observed. In flocks with brown hens, mites gathered at the lower tiers, whereas they were found at the highest tiers in association with white hens. As the hens are attacked mainly at night-time the most likely explanation is that the mites adjust their behavioural pattern to the birds' roosting behaviour.

  14. Biosecurity Assessment and Seroprevalence of Respiratory Diseases in Backyard Poultry Flocks Located Close to and Far from Commercial Premises.

    Science.gov (United States)

    Derksen, T; Lampron, R; Hauck, R; Pitesky, M; Gallardo, R A

    2018-03-01

    Raising backyard chickens is an ever-growing hobby in the United States. These flocks can be a substrate for respiratory disease amplification and transmission to commercial facilities. Five hundred fifty-four chickens from 41 backyard flocks were sampled in this study. ELISA kits were used to detect antibodies against avian influenza (AI), infectious laryngotracheitis (ILT), Newcastle disease (ND), infectious bronchitis (IB), Ornithobacterium rhinotracheale (ORT), Mycoplasma gallisepticum (MG), and Mycoplasma synoviae (MS). All visited flock owners answered a biosecurity questionnaire that assessed biosecurity measures. The questionnaire revealed that backyard poultry owners lack simple biosecurity measures such as use of dedicated shoes, their chicken sources are unreliable, and few of them benefit from veterinary oversight. Only one flock had a clear vaccination history against ND and IB. ORT, ND, IB, MS, MG, and ILT were the most seroprevalent in backyard poultry flocks with 97% (41/42), 77.5% (31/40), 75% (30/40), 73% (31/42), 69% (29/42), and 45% (19/42), respectively. The vaccinated flock was not considered in these calculations. When examining the distance between backyard flocks and the nearest commercial poultry facility, ND and MG were significantly more likely to be found in backyard flocks close to (4 miles) commercial poultry. Birds purchased directly from National Poultry Improvement Plan hatcheries showed a reduced ND, MG, and MS antibody prevalence. Wearing dedicated shoes decreased MS antibody-positive birds. Finally, history of wild bird contact had a clear effect on an increased seroprevalence of NDV and MG. Serological results suggest that backyard poultry flocks have the potential to serve as a reservoir or amplifier for poultry respiratory diseases. The information generated in this project should direct extension efforts toward emphasizing the importance of small flock biosecurity and chick acquisition sources.

  15. Novel Textile Scaffolds Generated by Flock Technology for Tissue Engineering of Bone and Cartilage.

    Science.gov (United States)

    Walther, Anja; Hoyer, Birgit; Springer, Armin; Mrozik, Birgit; Hanke, Thomas; Cherif, Chokri; Pompe, Wolfgang; Gelinsky, Michael

    2012-03-22

    Textile scaffolds can be found in a variety of application areas in regenerative medicine and tissue engineering. In the present study we used electrostatic flocking-a well-known textile technology-to produce scaffolds for tissue engineering of bone. Flock scaffolds stand out due to their unique structure: parallel arranged fibers that are aligned perpendicularly to a substrate, resulting in mechanically stable structures with a high porosity. In compression tests we demonstrated good mechanical properties of such scaffolds and in cell culture experiments we showed that flock scaffolds allow attachment and proliferation of human mesenchymal stem cells and support their osteogenic differentiation. These matrices represent promising scaffolds for tissue engineering.

  16. From phase to microphase separation in flocking models: the essential role of nonequilibrium fluctuations.

    Science.gov (United States)

    Solon, Alexandre P; Chaté, Hugues; Tailleur, Julien

    2015-02-13

    We show that the flocking transition in the Vicsek model is best understood as a liquid-gas transition, rather than an order-disorder one. The full phase separation observed in flocking models with Z(2) rotational symmetry is, however, replaced by a microphase separation leading to a smectic arrangement of traveling ordered bands. Remarkably, continuous deterministic descriptions do not account for this difference, which is only recovered at the fluctuating hydrodynamics level. Scalar and vectorial order parameters indeed produce different types of number fluctuations, which we show to be essential in selecting the inhomogeneous patterns. This highlights an unexpected role of fluctuations in the selection of flock shapes.

  17. Energy utilization and heat production of embryos from eggs originating from young and old broiler breeder flocks.

    Science.gov (United States)

    Nangsuay, A; Meijerhof, R; Ruangpanit, Y; Kemp, B; van den Brand, H

    2013-02-01

    Two experiments were conducted to study the interaction between breeder age and egg size on the energy utilization (experiment 1) and heat production (experiment 2) of broiler embryos. In experiment 1, a total of 4,800 Ross-308 hatching eggs from 2 breeder ages (29 and 53 wk of age, or young and old) and, within each age, 2 egg sizes (57 to 61 g and 66 to 70 g, or small and large) were used. In experiment 2, a total of 240 Ross-308 hatching eggs from 2 breeder flocks at 29 (young) and 53 (old) wk of age, and which were selected from the same egg weight range (58 to 61 g), were tested in 2 replicate chambers. In experiment 1, it was shown that the amount of yolk relative to albumen was higher in the old flock eggs, and this effect was more pronounced in the large eggs. The old flock eggs, especially the larger egg size, contained more energy as a result of a greater yolk size. Energy utilization of the embryos was positively related to yolk size and the amount of energy transferred to yolk-free body (YFB) was largely determined by the available egg energy. The efficiency of converting egg energy into chick body energy (E(YFB)) was equal for both egg sizes and both breeder age groups. Chick YFB weight of young and old flock eggs was equal. However, dry YFB weight of chicks from old flock eggs was higher than in chicks from young flock eggs, which was associated with more protein and fat content and thus more energy accumulated into YFB. As a consequence, embryos derived from old flock eggs produced more heat from d 16 of incubation onward than those of the young flock eggs. In conclusion, the higher energy deposition into chick YFB of old flock eggs, leading to higher embryonic heat production, is the result of a higher amount of available energy in the egg and is not due to changes in E(YFB).

  18. EFFECT OF THE DIETARY PELLET:MEAL RATIO ON THE PRODUCTIVE PERFORMANCE OF LAYING HENS

    Directory of Open Access Journals (Sweden)

    Luis Armando Sarmiento-Franco

    2009-07-01

    Full Text Available The effect of dietary pellet:meal ratio on the performance of laying hens was evaluated using 60 Plymouth Barred Rock 30 week old hens. Hens were distributed at random to three treatments: 100:0, 75:25 and 50:50% of pellet:meal ratio in the diet along 49 days, with 20 replicates each. Final body weight of hens, polar and ecuatorial diameters of the egg, eggshell weight, eggshell thickness, and yolk colour were not different between treatments (p>0.05. However, egg production, egg weight, egg mass, food consumption, food conversion and production cost were affected by treatments (p

  19. Motivation of hens to obtain feed during a molt induced by feed withdrawal, wheat middlings, or melengestrol acetate.

    Science.gov (United States)

    Koch, J M; Lay, D C; McMunn, K A; Moritz, J S; Wilson, M E

    2007-04-01

    Traditionally, molting was initiated by withdrawing feed. However, public criticism of feed deprivation, based on the perception that it inhumanely increases hunger, has led the poultry industry to ban the practice. Thus far, alternatives have not been demonstrated to ameliorate the increase in hunger that led to the ban on inducing molting by feed deprivation. Incorporating melengestrol acetate (MGA), an orally active progestin, into a balanced layer diet induces molting and increases postmolt egg quality. Hy-Line W-98 hens (n = 60) were randomly assigned to a balanced layer ration (control), a balanced layer ration containing MGA, or a 94% wheat middlings diet (wheat) for 20 d, or were feed deprived for 8 d. Hens were trained to peck a switch to receive a feed reward based on a progressive ratio reinforcement schedule. Motivation of hens to acquire feed was measured as the total number of pecks recorded in 15 min on d 0, 4, 8, 12, 16, and 20. On d 20, abdominal fat pad and digesta-free gizzards were weighed. The number of pecks in the feed-deprived group was greater than controls by d 4 and remained greater at d 8, when these hens were removed from the experiment. Hens in the wheat group that were rewarded with a layer diet pecked more than controls from d 8 to 20. Hens in the MGA group pecked for a reward at the same rate as control hens throughout the experiment. Hens fed the wheat diet had heavier gizzards compared with control and MGA-fed hens. Hens fed MGA had greater abdominal fat pad compared with wheat and control hens. Hens molted using a diet containing MGA have a similar motivation to obtain feed as control hens; therefore, this alternative does not appear to increase hunger. However, hens molted with a wheat middling diet appear to be as motivated to obtain feed as did the feed-deprived hens.

  20. Variability in amino acid digestibility and metabolizable energy of corn studied in cecectomized laying hens1.

    Science.gov (United States)

    Zuber, T; Rodehutscord, M

    2017-06-01

    To optimize the use of corn grain in diets for laying hens, differences in amino acid (AA) digestibility and metabolizable energy among different corn samples should be considered in feed formulation. The present study investigated the variability of AA digestibility and AMEn concentration of 20 corn samples in cecectomized laying hens. Corn grains were characterized based on their physical properties (thousand seed weight, test weight, grain density, and extract viscoelasticity), chemical composition (proximate nutrients, AA, minerals, and inositol phosphates), gross energy concentration, and in vitro solubility of nitrogen to study any relationship with AA digestibility or AMEn. The animal study comprised 4 Latin squares (6 × 6) distributed between 2 subsequent runs. Cecectomized LSL-Classic hens were individually housed in metabolism cages and fed either a basal diet containing 500 g/kg cornstarch or one of 20 corn diets, each replacing the cornstarch with one corn batch, for 8 days. During the last 4 d, feed intake was recorded and excreta were collected quantitatively. A linear regression approach was used to calculate AA digestibility of the corn. The digestibility of all AA differed significantly between the 20 corn batches, including Lys (digestibility range 64 to 85%), Met (86 to 94%), Thr (72 to 89%), and Trp (21 to 88%). The AMEn of the corn batches ranged between 15.7 and 17.1 MJ/kg DM. However, consistent correlations between AA digestibility or AMEn and the physical and chemical characteristics of the grains were not detected. Equations to predict AA digestibility or AMEn based on the grain's physical and chemical characteristics were calculated by multiple linear regressions. The explanatory power (adjusted R2;) of prediction equations was below 0.6 for the majority of AA and AMEn, and, thus, was not sufficiently precise for practical use. Possible explanations for the variation in AA digestibility and AMEn beyond the determined characteristics

  1. Biochemical Parameters and Histopathological Findings in the Forced Molt Laying Hens

    Directory of Open Access Journals (Sweden)

    N Mert

    Full Text Available ABSTRACT The aim of this study was to evaluate the effects of forced molting using biochemical parameters and histopathological findings in laying hens. 36 Hyline W36 strain laying hens, 90 weeks old were chosen for this research. Eight of these chickens were randomly selected and placed in a cage as the control group before the molting program began. All the others 28 chickens were used for the forced molting program. Eight laying hens were slaughtered at the end of the molting program named as molting group. The remaining 20 hens were fed for 37 days, weighted and slaughtered when they reached the maximum egg production (80% as postmolting group. Then, blood was analyzed for malondialdehyde, glutathione, catalase, glucose, calcium, phosphorus, albumin, globulin, total protein, triiodothyronine, thyroxine and Vitamin C. The malondialdehyde and glutathione levels of the thyroid and liver tissues were also analyzed along with an examination of the histopathological changes of the liver, ovarium and thyroid glands; and live body, liver, ovarium, thyroid weights and thyroid lengths. In conclusion, it was found that forced molting produces stress and notable side effects in hens, like the oxidant and antioxidant status of the organs, tissue weights and sizes, hormon profiles, blood biochemical and histopathological parameter changes. The activities of thyroid malondialdehyde (p<0.05, liver glutathione (p<0.01, plasma catalase (p<0.001 were significantly decreased in molting group compared to control values, while liver malondialdehyde levels were significantly increased (p<0.001 and thyroid glutathione levels had nonsignificant effect. These levels in molting hens were the first study for veterinary science.

  2. Radiocaesium variability in upland sheep flocks

    Energy Technology Data Exchange (ETDEWEB)

    Beresford, N.A

    2002-07-01

    Following the 1986 Chernobyl accident large areas of uplands in the United Kingdom were contaminated by radiocaesium. Consequently, the level of radiocaesium in the tissues of some sheep exceeded 1000 Bq kg{sup -1} fresh weight This is the limit adopted within the UK above which meat cannot enter the food chain. In 1986, restrictions were placed on the movement and slaughter of sheep in areas of west Cumbria, north Wales and Scotland. Whilst the number of farms under restriction has reduced considerably, some still remain restricted in 2002. Although a number of workers had noted considerable variability between the radiocaesium activities of individuals within sheep flocks there had been no analyses of causal effects. The work described here, combined studies on three upland farms within west Cumbria with controlled feeding experiments, to systematically assess the parameters which may contribute to such variability. Results from all three farms demonstrate a temporally consistent ranking of the {sup 137}Cs activity concentration of individual sheep within the study flocks. As there was also a correlation between the {sup 137}Cs activity concentration of ewes and their pre-weaned lambs it is likely that the same ewes are producing lambs in excess of the intervention limit in subsequent years. It is difficult to generalise as to which factors will contribute to {sup 137}Cs variability within a given upland flock; factors contributing to variation were not consistent between the study farms. However, the location grazed and/or vegetation selected by animals was a causal factor to the observed variability at all three farms. The transfer of radiocaesium from the diet to muscle of sheep was found to be determined by live-weight change and dry matter intake. Subsequent studies have suggested that protein turnover may be a potential mechanism for the relationship between dry matter intake and radiocaesium transfer. This hypothesis is supported by current understanding

  3. Radiocaesium variability in upland sheep flocks

    International Nuclear Information System (INIS)

    Beresford, N.A.

    2002-01-01

    Following the 1986 Chernobyl accident large areas of uplands in the United Kingdom were contaminated by radiocaesium. Consequently, the level of radiocaesium in the tissues of some sheep exceeded 1000 Bq kg -1 fresh weight This is the limit adopted within the UK above which meat cannot enter the food chain. In 1986, restrictions were placed on the movement and slaughter of sheep in areas of west Cumbria, north Wales and Scotland. Whilst the number of farms under restriction has reduced considerably, some still remain restricted in 2002. Although a number of workers had noted considerable variability between the radiocaesium activities of individuals within sheep flocks there had been no analyses of causal effects. The work described here, combined studies on three upland farms within west Cumbria with controlled feeding experiments, to systematically assess the parameters which may contribute to such variability. Results from all three farms demonstrate a temporally consistent ranking of the 137 Cs activity concentration of individual sheep within the study flocks. As there was also a correlation between the 137 Cs activity concentration of ewes and their pre-weaned lambs it is likely that the same ewes are producing lambs in excess of the intervention limit in subsequent years. It is difficult to generalise as to which factors will contribute to 137 Cs variability within a given upland flock; factors contributing to variation were not consistent between the study farms. However, the location grazed and/or vegetation selected by animals was a causal factor to the observed variability at all three farms. The transfer of radiocaesium from the diet to muscle of sheep was found to be determined by live-weight change and dry matter intake. Subsequent studies have suggested that protein turnover may be a potential mechanism for the relationship between dry matter intake and radiocaesium transfer. This hypothesis is supported by current understanding of protein-dry matter

  4. Effect of corticosterone on gene expression of feed intake regulatory peptides in laying hens.

    Science.gov (United States)

    Liu, Lei; Song, Zhigang; Sheikhahmadi, Ardashir; Jiao, Hongchao; Lin, Hai

    2012-08-01

    The present study was conducted to explore the effects of corticosterone (CORT) on the regulation of appetite-associated genes in laying hens. Forty eight laying hens were randomly divided into two groups: one received subcutaneous injection of CORT (2mg/kg body weight, CORT-exposed) and the other received sham-treatment (Control). Treatment of hens with CORT stimulated an increase (P0.05) on the mRNA levels of neuropeptide Y (NPY), corticotropin-releasing hormone (CRH), melanocortin receptor 4 and 5 (MCR-4 and MCR-5) and cholecystokinin (CCK) in the hypothalamus when compared with control hens. However, the expression of pro-opiomelanocortin (POMC), agouti-related protein (AgRP) and melanocortin recepter 1 (MCR-1) were significantly (Phens. Treatment of laying hens with CORT had no significant (P>0.05) effect on the mRNA levels of CCK in the glandular stomach and the duodenum, and those of ghrelin in the glandular stomach, the duodenum and the jejunum. However, the mRNA levels of CCK in the jejunum and the ileum, and those of ghrelin in the ileum were significantly (Pfeeding status of CORT-exposed laying hens. Copyright © 2012 Elsevier Inc. All rights reserved.

  5. The layering and physical characteristics of Shaver Brown Hens in a ...

    African Journals Online (AJOL)

    Eggs were collected from 120 Shaver Brown hens for a period of 56 days in order to determine their oviposition time, sequence of laying, lag time, laying intensity and egg weight. The hens were subsequently divided into three classes on the basis of their laying performance namely: good layers, intermediate layers and ...

  6. Intracellular lipid dysregulation interferes with leukocyte function in the ovaries of meat-type hens under unrestricted feed intake.

    Science.gov (United States)

    Liu, Zu-Chen; Su, Chia-Ming; Xie, Yi-Lun; Chang, Chai-Ju; Chen, Jiang-Young; Wu, Shu-Wei; Chen, Yu-Hui; Walzem, Rosemary L; Huang, San-Yuan; Chen, Shuen-Ei

    2016-04-01

    Meat-type Red-feather country hens fed ad libitum (AD-hens) exhibit obesity-associated morbidities and a number of ovarian irregularities. Leukocyte participations in ovarian activities are unstudied in AD-hens. In contrast to feed-restricted hens (R-hens), ovulatory process of the F1 follicle appeared delayed in AD-hens in association with reduced F1 follicle progesterone content, gelatinase A (MMP-2) and collagenase-3 (MMP-13) activities coincident with elevated IL-1β and no production (Pcultures of granulosa cells with increasing numbers of leukocytes from either AD-hens or R-hens exhibited dose dependent reductions in progesterone production and increases in cell death. AD-hen leukocytes were less proapoptotic than their R counterparts (Pcultures with heterophils or monocytes in a dose-dependent manner (Pcultures than their respective counterparts (P<0.05). Both basal and LPS-induced IL-1β secretion and MMP-22 or MMP-2 activities in freshly isolated AD-hen leukocytes were reduced (P<0.05). Exposure of AD or R leukocytes to 0.5mM palmitate impaired IL-1β secretion and MMP-22 or MMP-2 activity. Inhibition of ceramide synthesis with FB1 and ROS production with n-MPG scavenging rescued MMP activity and IL-1β production in palmitate treated heterophils, but exacerbated monocyte suppression. These latter findings suggest that intracellular lipid dysregulation in leukocytes contributes to ovarian dysfunction in AD-hens. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Flocking in Multi-Agent Systems with Multiple Virtual Leaders Based Only on Position Measurements

    International Nuclear Information System (INIS)

    Su Housheng

    2012-01-01

    Most existing flocking algorithms assume one single virtual leader and rely on information on both relative positions and relative velocities among neighboring agents. In this paper, the problem of controlling a flock of mobile autonomous agents to follow multiple virtual leaders is investigated by using only position information in the sense that agents with the same virtual leader asymptotically attain the same velocity and track the corresponding virtual leader based on only position measurements. A flocking algorithm is proposed under which every agent asymptotically attains its desired velocity, collision between agents can be avoided, and the final tight formation minimizes all agents' global potentials. A simulation example is presented to verify and illustrate the theoretical results. (general)

  8. Effects of alkoxy alkyl mercury derivative on hens in a feed test with disinfected cereal

    Energy Technology Data Exchange (ETDEWEB)

    Ring, O; Kalliokoski, P K

    1968-01-01

    Experiments were performed to determine the effects of feeding hens cereal that had been disinfected with either methoxyethyl mercury chloride or methoxyethyl mercury silicate. Two groups of hens were fed the grain and the results were compared. Both disinfectants decreased egg production and consumption of the feed. Two-thirds of the hens lost weight in the methoxyethyl mercury silicate test. The hens were not weighed in the other test. Estimated intakes of Hg were 2.5 mg for methoxyethyl mercury chloride and 0.45 mg for methoxyethyl mercury silicate.

  9. Isolation of Campylobacter from Brazilian broiler flocks using different culturing procedures.

    Science.gov (United States)

    Vaz, C S L; Voss-Rech, D; Pozza, J S; Coldebella, A; Silva, V S

    2014-11-01

    Conventional culturing methods enable the detection of Campylobacter in broiler flocks. However, laboratory culture of Campylobacter is laborious because of its fastidious behavior and the presence of competing nontarget bacteria. This study evaluated different protocols to isolate Campylobacter from broiler litter, feces, and cloacal and drag swabs. Samples taken from commercial Brazilian broiler flocks were directly streaked onto Preston agar (PA), Campy-Line agar (CLA), and modified charcoal cefoperazone deoxycholate agar (mCCDA) and also enriched in blood-free Bolton broth (bfBB) for 24 and 48 h followed by plating onto the different selective media. Higher numbers of Campylobacter-positive cloacal and drag swab samples were observed using either direct plating or enrichment for 24 h before plating onto PA, compared with enrichment for 48 h (P media. Together, these data showed that direct plating onto PA and onto either CLA or mCCDA as the second selective agar enabled the reliable isolation of thermophilic Campylobacter species from broiler samples. Finally, Campylobacter was detected in all broiler flocks sampled. ©2014 Poultry Science Association Inc.

  10. Flocking small smart machines: An experiment in cooperative, multi-machine control

    International Nuclear Information System (INIS)

    Klarer, P.R.

    1998-03-01

    The intent and purpose of this work was to investigate and demonstrate cooperative behavior among a group of mobile robot machines. The specific goal of this work was to build a small swarm of identical machines and control them in such a way as to show a coordinated movement of the group in a flocking manner, similar to that observed in nature. Control of the swarm's individual members and its overall configuration is available to the human user via a graphic man-machine interface running on a base station control computer. Any robot may be designated as the nominal leader through the interface tool, which then may be commanded to proceed to a particular geographic destination. The remainder of the flock follows the leader by maintaining their relative positions in formation, as specified by the human controller through the interface. The formation's configuration can be altered manually through an interactive graphic-based tool. An alternative mode of control allows for teleoperation of one robot, with the flock following along as described above

  11. Increased Toxoplasma gondii positivity relative to age in 125 Scottish sheep flocks; evidence of frequent acquired infection

    Science.gov (United States)

    2011-01-01

    Toxoplasma gondii seroprevalence was determined in 3333 sheep sera from 125 distinct sheep flocks in Scotland, with the majority of flocks being represented by 27 samples, which were collected between July 2006 and August 2008. The selected farms give a representative sample of 14 400 sheep holdings identified in the Scottish Government census data from 2004. Overall T. gondii seroprevalence, at individual sheep level, was determined to be 56.6%; each flock tested, had at least a single positive animal and in four flocks all ewes tested positive. The seroprevalence of sheep increased from 37.7% in one year old stock to 73.8% in ewes that were older than six years, showing that acquired infections during the life of the animals is frequent and that environmental contamination by T. gondii oocysts must be significant. The median within-flock seroprevalence varied significantly across Scotland, with the lowest seroprevalence of 42.3% in the South and the highest seroprevalence of 69.2% in the far North of Scotland and the Scottish Islands, while the central part of Scotland had a seroprevalence of 57.7%. This distribution disequilibrium may be due to the spread and survival of oocysts on pasture and lambing areas. A questionnaire accompanying sampling of flocks identified farms that used Toxovax®, a commercial vaccine that protects sheep from abortion due to T. gondii infection. Only 24.7% of farmers used the vaccine and the vaccine did not significantly affect the within flock seroprevalence for T. gondii. The implications for food safety and human infection are discussed. PMID:22189159

  12. Enantioselective Characteristics and Montmorillonite-Mediated Removal Effects of α-Hexachlorocyclohexane in Laying Hens.

    Science.gov (United States)

    Liu, Xueke; Shen, Zhigang; Wang, Peng; Liu, Chang; Yao, Guojun; Zhou, Zhiqiang; Liu, Donghui

    2016-06-07

    α-Hexachlorocyclohexane (α-HCH) is a chiral organochlorine pesticide that is often ubiquitously detected in various environmental matrices and may be absorbed by the human body via food consumption, with serious detriments to human health. In this study, enantioselective degradation kinetics and residues of α-HCH in laying hens were investigated after a single dose of exposure to the pesticide, whereas enantioselectivity and residues of α-HCH in eggs, droppings, and various tissues were investigated after long-term exposure. Meanwhile, montmorillonite (MMT), a feed additive with high capacity of adsorption, was investigated for its ability to remove α-HCH from laying hens. Most non-brain tissues enantioselectively accumulated (-)-α-HCH, while (+)-α-HCH was preferentially accumulated in the brain. The enantiomer fractions (EFs) in most tissues gradually decreased, implying continuous depletion of (+)-α-HCH in laying hens. After 30 days of exposure and 31 days of elimination, the concentration of α-HCH in eggs and tissues of laying hens with MMT-containing feed was lower than that with MMT-free feed, indicating the removal effects of MMT for α-HCH in laying hens. The findings presented herein suggest that modified MMT may potentially be useful in reducing the enrichment of α-HCH in laying hens and eggs, thus lowering the risk of human intake of α-HCH.

  13. Identification and phylogenetic diversity of parvovirus circulating in commercial chicken and turkey flocks in Croatia.

    Science.gov (United States)

    Bidin, M; Lojkić, I; Bidin, Z; Tiljar, M; Majnarić, D

    2011-12-01

    Phylogenetic diversity of parvovirus detected in commercial chicken and turkey flocks is described. Nine chicken and six turkey flocks from Croatian farms were tested for parvovirus presence. Intestinal samples from one turkey and seven chicken flocks were found positive, and were sequenced. Natural parvovirus infection was more frequently detected in chickens than in turkeys examined in this study. Sequence analysis of 400 nucleotide fragments of the nonstructural gene (NS) showed that our sequences had more similarity with chicken parvovirus (ChPV) (92.3%-99.7%) than turkey parvovirus (TuPV) (89.5%-98.9%) strains. Phylogenetic analysis grouped our sequences in two clades. Also, the higher prevalence of ChPV than TuPV in tested flocks was defined. The necropsy findings suggested a malabsorption syndrome followed by a preascitic condition. Further research of parvovirus infection, pathogenesis, and the possibility of its association with poult enteritis and mortality syndrome (PEMS) and runting and stunting syndrome (RSS) is needed to clarify its significance as an agent of enteric disease.

  14. A Screen-Peck Task for Investigating Cognitive Bias in Laying Hens.

    Directory of Open Access Journals (Sweden)

    Amanda Deakin

    Full Text Available Affect-induced cognitive judgement biases occur in both humans and animals. Animals in a more negative affective state tend to interpret ambiguous cues more negatively than animals in a more positive state and vice versa. Investigating animals' responses to ambiguous cues can therefore be used as a proxy measure of affective state. We investigated laying hens' responses to ambiguous stimuli using a novel cognitive bias task. In the 'screen-peck' task, hens were trained to peck a high/low saturation orange circle presented on a computer screen (positive cue-P to obtain a mealworm reward, and to not peck when the oppositely saturated orange circle was presented (negative cue-N to avoid a one second air puff. Ambiguous cues were orange circles of intermediate saturation between the P and N cue (near-positive-NP; middle-M; near-negative-NN, and were unrewarded. Cue pecking showed a clear generalisation curve from P through NP, M, NN to N suggesting that hens were able to associate colour saturation with reward or punishment, and could discriminate between stimuli that were more or less similar to learnt cues. Across six test sessions, there was no evidence for extinction of pecking responses to ambiguous cues. We manipulated affective state by changing temperature during testing to either ~20°C or ~29°C in a repeated measures cross-over design. Hens have been shown to prefer temperatures in the higher range and hence we assumed that exposure to the higher temperature would induce a relatively positive affective state. Hens tested under warmer conditions were significantly more likely to peck the M probe than those tested at cooler temperatures suggesting that increased temperature in the ranges tested here may have some positive effect on hens, inducing a positive cognitive bias.

  15. Feed intake alters immune cell functions and ovarian infiltration in broiler hens: implications for reproductive performance.

    Science.gov (United States)

    Liu, Zu-Chen; Xie, Yi-Lun; Chang, Chai-Ju; Su, Chia-Ming; Chen, Yu-Hui; Huang, San-Yuan; Walzem, Rosemary L; Chen, Shuen-Ei

    2014-06-01

    Leukocytes are known to participate in ovarian activities in several species, but there is a surprising lack of information for the common chicken. Broiler hens consuming feed ad libitum (AL) exhibit a number of ovarian irregularities, but leukocyte functions are unstudied. In contrast to feed-restricted (R) hens, AL feeding for 7 wk significantly reduced egg production and clutch length while increasing pause length and atretic follicle numbers (P hens contained less progesterone, and follicle walls were thicker with loose fibrous morphology and had less collagenase-3-like gelatinolytic activity but more IL-1beta (P hen peripheral heterophils and monocytes (P hens. © 2014 by the Society for the Study of Reproduction, Inc.

  16. Paul Henning Krogh on Soil Ecotoxicology

    DEFF Research Database (Denmark)

    Krogh, Paul Henning

    2008-01-01

    In a recent analysis of data from Essential Science Indicators SM from Thomson Reuters , Dr. Paul Henning Krogh was named a Rising Star in the field of Environment & Ecology. His current record in this field includes 48 papers cited a total of 410 times. Dr. Krogh is a Senior Scientist in the Dep......In a recent analysis of data from Essential Science Indicators SM from Thomson Reuters , Dr. Paul Henning Krogh was named a Rising Star in the field of Environment & Ecology. His current record in this field includes 48 papers cited a total of 410 times. Dr. Krogh is a Senior Scientist...... in the Department of Terrestrial Ecology at the National Environmental Research Institute, part of the University of Aarhus in Silkeborg, Denmark. This month, he talks with ScienceWatch.com correspondent Simon Mitton about his highly cited work. View Article...

  17. Effect of diatomaceous earth on parasite load, egg production, and egg quality of free-range organic laying hens.

    Science.gov (United States)

    Bennett, D C; Yee, A; Rhee, Y-J; Cheng, K M

    2011-07-01

    The effectiveness of diatomaceous earth (DE) as a treatment against parasites and to increase feed efficiency and egg production of organically raised free-range layer hens was evaluated in 2 breeds of commercial egg layers [Bovan Brown (BB) and Lowmann Brown (LB)] that differ in their resistance to internal parasitic infections. Half the hens of each breed were fed diets supplemented with DE (2%). Their internal parasite loads were assessed by biweekly fecal egg counts (FEC) and by postmortem examination of the gastrointestinal tract. Supplementing DE in diets of LB hens, the more parasite-resistant breed, did not significantly affect their FEC and adult parasite load. However, BB hens treated with dietary DE had significantly lower Capillaria FEC, slightly lower Eimeria FEC, fewer birds infected with Heterakis, and significantly lower Heterakis worm burden than control BB hens. Both BB and LB hens fed the diet containing DE were significantly heavier, laid more eggs, and consumed more feed than hens fed the control diet, but feed efficiency did not differ between the 2 dietary treatments. Additionally, BB hens consuming the DE diet laid larger eggs containing more albumen and yolk than hens consuming the control diet. In a subsequent experiment, the effectiveness of DE to treat a Northern fowl mite (Ornithonyssus sylviarum) infestation was tested. Relative to controls, both breeds of hens that were dusted with DE had reduced number of mites. The results of this study indicate the DE has the potential to be an effective treatment to help control parasites and improve production of organically raised, free-range layer hens.

  18. Performance And Egg Quality Of Hens Fed Cocoa Husk Based Diet ...

    African Journals Online (AJOL)

    Lowman Brown hens, 37 - week - old, were used to study the effect of dietary inclusion of 10 and 20% cocoa husk meal (CHM) at the expense of maize on hen performance and egg quality. The trial was conducted for 10 weeks. Egg production (EP), egg weight (EW), egg mass (EM), feed consumption (FC), and feed ...

  19. "We're just targeted as the flock that has HIV": health care experiences of members of the house/ball culture.

    Science.gov (United States)

    Rowan, Diana; DeSousa, Maysa; Randall, Ethan Makai; White, Chelsea; Holley, Lamont

    2014-01-01

    The house/ball community is an understudied sub-group of young Black men who have sex with men and transgender persons in urban centers of the United States who affiliate in social structures called houses and gather at elaborate dance and performance events called balls. In Charlotte, North Carolina, 12 house/ball members were interviewed about their experiences with health care providers and their assessment of any barriers to care due to their affiliation with the rather clandestine house/ball sub-culture. Additionally, HIV-specific health care providers were interviewed, to assess their knowledge of the sub-culture. House/ball members reported both positive and negative perceptions of treatment by their health care providers with respect to their house/ball involvement. Some reported feeling stigmatized, especially around HIV status. Results showed that increased knowledge about the house/ball community could improve practitioners' cultural competence, thereby reducing stigma-related barriers to care.

  20. INFRARED SPECTROSCOPY OF SYMBIOTIC STARS. XI. ORBITS FOR SOUTHERN S-TYPE SYSTEMS: HEN 3-461, SY MUS, HEN 3-828, AND AR PAV

    International Nuclear Information System (INIS)

    Fekel, Francis C.; Hinkle, Kenneth H.; Joyce, Richard R.; Wood, Peter R.

    2017-01-01

    Employing new infrared radial velocities, we have computed spectroscopic orbits of the cool giants in four southern S-type symbiotic systems. The orbits for two of the systems, Hen 3-461 and Hen 3-828, have been determined for the first time, while orbits of the other two, SY Mus and AR Pav, have previously been determined. For the latter two systems, we compare our results with those in the literature. The low mass of the secondary of SY Mus suggests that it has gone through a common envelope phase. Hen 3-461 has an orbital period of 2271 days, one of the longest currently known for S-type symbiotic systems. That period is very different from the orbital period proposed previously from its photometric variations. The other three binaries have periods between 600 and 700 day, values that are typical for S-type symbiotic orbits. Basic properties of the M giant components and the distance to each system are determined.

  1. Genetic correlations between behavioural responses and performance traits in laying hens

    Directory of Open Access Journals (Sweden)

    Iwona Rozempolska-Rucińska

    2017-12-01

    Full Text Available Objective The aim of the study was to evaluate genetic correlations between the behavioural profile and performance in laying hens as an indirect answer to the question whether the observed behavioural responses are associated with increased levels of stress in these birds. Methods The assessment of birds’ temperament was carried out using the novel objects test. The behavioural test was conducted in two successive generations comprising 9,483 Rhode Island White (RIW birds (approx. 4,700 individuals per generation and 4,326 Rhode Island Red (RIR birds (approx. 2,100 individuals per generation. Based on the recorded responses, the birds were divided into two groups: a fearful profile (1,418 RIW hens and 580 RIR hens and a brave/curious profile (8,065 RIW hens and 3,746 RIR hens. The birds were subjected to standard assessment of their performance traits, including SM, age at sexual maturity; ST, shell thickness; SG, egg specific gravity; EW, mean egg weight; IP, initial egg production; and HC, number of hatched chicks. The pedigree was three generations deep (including two behaviour-recorded generations. Estimation of the (covariance components was performed with the Gibbs sampling method, which accounts for the discrete character of the behavioural profile denotation. Results The analyses revealed negative correlations between the performance traits of the laying hens and the behavioural profile defined as fearful. In the group of fearful RIW birds, delayed sexual maturation (0.22 as well as a decrease in the initial egg production (−0.30, egg weight (−0.54, egg specific gravity (−0.331, shell thickness (−0.11, and the number of hatched chicks (−0.24 could be expected. These correlations were less pronounced in the RIR breed, in which the fearful birds exhibited a decline in hatchability (−0.37, egg specific gravity (−0.11, and the number of hatched chicks (−0.18. There were no correlations in the case of the other traits or

  2. Fatal systemic cladosporiosis in a merino sheep flock.

    Science.gov (United States)

    Haligur, Mehmet; Ozmen, Ozlem; Dorrestein, Gerry M

    2010-12-01

    Systemic cladosporiosis is described in 25 merino sheep from a flock consisting 250 animals. The fungal pneumonia appeared after an intensive antibiotic treatment, because of a respiratory system disorder. The pen of the flock was humid and crowded, and animals had signs of respiratory distress, coughing, fever and anorexia. All of the ill animals died, and necropsy was performed on 10 sheep. The lesions were characterized by a multifocal pyogranulomatous pneumonia and an abomasitis. Severe hemorrhages were observed in the lungs. At the histopathological examination, severe vasculitis with thrombosis was observed in various organs, especially in the lungs and abomasums, suggestive for a hematogenous dissemination of the infection in these organs. Numerous PAS-positive fungal elements were seen in the pyogranulomatous foci. Dark green fungal colonies were seen in the blood agar and Sabouraud dextrose agar that were identified as Cladosporium cladosporioides. This report highlights that phaeohyphomycosis can cause a severe systemic and fatal disease in merino sheep under insufficient management conditions.

  3. Flock size, diet composition, and habitat characteristics of the ...

    African Journals Online (AJOL)

    gla- cial history (Magin 2001). Some of the plant species endemic to SMNP are stonecrop. Rosularia simiensis and tussock grass Festuca gilbertiana. SMNP is home to 22 species. Flock size, diet composition, and habitat characteristics of ...

  4. Maatregelen ter vermindering van fijnstofemissie uit de pluimveehouderij; studie naar mogelijkheden van aanbrengen waterfilm op strooisel = Measures to reduce fine dust emissions from poultry houses; possibility of supplying a waterfilm on litter

    NARCIS (Netherlands)

    Ellen, H.H.; Harn, van J.

    2010-01-01

    In this desk study the possibilities of reducing fine dust emission from poultry housings by applying a water film on bedding material was studied. This measure can be perspective in laying hens, but not in broilers and parent stock.

  5. Applying the principles of welfare and quality of production in the organic farm of the laying hens

    Directory of Open Access Journals (Sweden)

    Jana Zdechovanová

    2013-07-01

    Full Text Available European Union  banned with Council Directive No. 74/1999/EC use of the conventional battery cages for laying hens in European Union with effect from January 1, 2012. By this time much attention was paid to the assessment of laying hens welfare in the modified breeding system,namely from aspect of behavior and expression fyziological stress. At present are used the enriched cages,   which device is defined by the Code of laying hens living conditions. Quantification of intensity and sequence of the events in different behaviour and a time regime can contribute to knowledge of time spending of the laying hens  in the breeding area and to determining of prioritizing their behavior.The aim of our research was assessment an application of principles laying hens welfare in the farm, their production and egg quality. An object of investigation was ecological farm of laying hens. In the experiment were observed thehousing conditions and nutrition of laying hens in farm, egg production, egg weight at laying hens old 42 weeks and selected indicators of chemical formation of the eggs. In the farm were reared laying hens ISA Brown, which are high-productive and the most   the most widely used in EU. The informations and data on farm, laying hen hall, breeding facility, breeding conditions, the behavior of the laying hens, nutrition, feeding and egg production were obtained by personal visit an organic farm and informations which  the farmer records and stores. The informations about the behavior of laying hens were obtained by observing and comparing with the knowledge and data of the Slovak Government regulation on December 11, 2002, which   minimum standards determine for the protection of laying hens.The informations on feed were obtained  directly from an organic farm and   feed company that followed by accordance  the minimum content of nutrients and energy in accordance with the needs of the laying hens. Egg production was

  6. Field estimation of the flock-level diagnostic specificity of an enzyme-linked immunosorbent assay for Avian metapneumovirus antibodies in turkeys.

    Science.gov (United States)

    Muñoz-Zanzi, Claudia; Trampel, Darrell; Hanson, Tim; Harrison, Kristen; Goyal, Sagar; Cortinas, Roberto; Lauer, Dale

    2009-03-01

    Routine serologic testing for Avian metapneumovirus (AMPV) infection of turkey flocks at slaughter is currently being used to monitor changes in the occurrence of AMPV infection in endemic areas and can also be used to detect the emergence of infection in currently unaffected areas. Because of the costs associated with false-positive results, particularly in areas that are free of AMPV infection, there is a need to obtain improved estimates of flock-level specificity (SP). The objective of this study was to estimate flock-level SP of a program to monitor AMPV infection in turkey flocks at processing using a standard enzyme-linked immunosorbent assay (ELISA). A study was carried out in which 37 AMPV-free flocks from 7 Midwest operations were followed serologically. Six percent, 3%, and 0.2% of total samples tested AMPV positive at 8 weeks, 12 weeks, and at processing, respectively. Overall, flock-level SP increased as the cutoff increased and as age increased. Flock-level SP at processing was 97%, if a cutoff of 1 was used (the flock was classified as positive if at least 1 sample tested positive), and 100%, if any other cutoff was used. Administration of antibiotics (P = 0.02) and vaccination for Bordetella avium (P = 0.08) were positively associated with the probability of (false) positive test results. These findings suggest possible cross-reactions with other infections and highlight the need to consider variable diagnostic performance depending on farm conditions.

  7. Evaluation of the performance of Hy-Line Brown laying hens fed soybean or soybean-free diets using cage or free-range rearing systems.

    Science.gov (United States)

    Al-Ajeeli, M N; Leyva-Jimenez, H; Abdaljaleel, R A; Jameel, Y; Hashim, M M; Archer, G; Bailey, C A

    2018-03-01

    This study evaluated egg production and quality variables of caged and free-range Hy-Line Brown laying hens fed soybean meal (SBM) and soybean-meal-free (SBMF) diets. Hens were randomly assigned to the same 2 dietary treatments within 3 location blocks. SBM and SBMF diets with equivalent calculated nutrient content were prepared based on Hy-Line Brown rearing guidelines. The SBMF diets utilized cottonseed meal, corn distillers dried grains with solubles, corn gluten meal, and wheat middlings in place of dehulled soybean meal. The experiment was conducted between August 2015 and January of 2016 within the TAMU Poultry Research Center and data analyzed over 6 consecutive 28-day periods. Data were analyzed as a split-plot with rearing systems designated whole plots and diets designated as subplots. Hens reared in the free-range rearing system peaked a couple of wk later than those hens within the more conventional indoor caged system, and cumulative production data were considerably more variable for hens raised in the free-range environment. Cumulative egg production, feed per dozen eggs and feed conversion ratio (g feed/g egg) were 92 ± 1.23 and 86 ± 1.84%, 1.45 ± 0.02 and 1.89 ± 0.05 kg, and 2.14 ± 0.04 and 2.77 ± 0.08 (P free-range rearing systems. Cumulative egg weight, feed per dozen eggs, and feed conversion ratio were 59.9 ± 0.59 and 56.5 ± 0.60 g, 1.57 ± 0.04 and 1.77 ± 0.05 kg, and 2.24 ± 0.06 and 2.67 ± 0.08 kg (P  0.05). With respect to egg quality, there were no differences in cumulative albumen height, Haugh unit, or breaking strength, but there was a significant rearing system by diet interaction for shell thickness, with the free-range hens averaging 40.77 ± 0.19 and 39.86 ± 0.31 μm (P free-range production is more variable than traditional closed-house cage systems based on standard errors, and SBMF diets containing cottonseed meal can be used in both caged and free-range production systems without

  8. 9 CFR 145.33 - Terminology and classification; flocks and products.

    Science.gov (United States)

    2010-01-01

    ... POULTRY Special Provisions for Multiplier Meat-Type Chicken Breeding Flocks and Products § 145.33... demonstrate pullorum or typhoid infection; (vii) All poultry, including exhibition, exotic, and game birds...

  9. Screening for hen's egg and chicken meat specific IgE antibodies in ...

    African Journals Online (AJOL)

    Background: Allergy to hen's egg and meat contributes significantly to the manifestations of food allergy all over the world. Objectives: This study was performed to assess the presence of hen's egg and meat specific IgE antibodies among patients investigated for various allergic disorders. Methods. This is a retrospective ...

  10. Screening for hen's egg and chicken meat specific IgE antibodies in ...

    African Journals Online (AJOL)

    Abstract. Background: Allergy to hen's egg and meat contributes significantly to the manifestations of food allergy all over the world. Objectives: This study was performed to assess the presence of hen's egg and meat specific IgE antibodies among patients investigated for various allergic disorders. Methods. This is a ...

  11. Using a feed-grade zinc propionate to achieve molt induction in laying hens and retain postmolt egg production and quality.

    Science.gov (United States)

    Park, S Y; Kim, W K; Birkhold, S G; Kubena, L F; Nisbet, D J; Ricke, S C

    2004-11-01

    A commercial-feed-grade form of zinc propionate was examined as a potential feed amendment at a concentration of 1% zinc to induce molt in 90-wk-old hens. Dietary treatments consisted of 4 treatment groups of 28 birds each randomly assigned to either (1) molted conventionally by feed withdrawal, (2) 1% zinc as Zn acetate, (3) 1% zinc as Zn propionate, or (4) nonmolted control for 9 d. Ovary weights of hens fed Zn acetate or Zn propionate were not significantly different from each other, but hens fed Zn acetate or Zn propionate were significantly (phens. Zinc concentrations in the kidney and liver were significantly (phens when compared to either nonmolted control-fed hens or feed-withdrawal molted hens. Over the entire 3-mo postmolt period, there were no significant differences in interior or exterior egg qualities among the four treatments. Egg production of hens fed Zn acetate was significantly lower than feed-withdrawal hens, Zn propionate-fed hens, or nonmolted control hens (pfeeding a feed grade of Zn propionate (1% Zn)-supplemented diet can induce molt and retain postmolt egg quality and production comparable to hens molted by feed withdrawal.

  12. Comparison of hen preference for nesting substrate material, and performance in a free range production system

    Science.gov (United States)

    This project consisted of 200 Hy-Line Brown hens and was conducted utilizing the brood-grow-lay range huts at the North Carolina Department of Agriculture and Consumer Services’ Piedmont Research Station. Fifty hens were placed in each pen/paddock providing 1338 cm2/hen of floor space in the hut an...

  13. Time-asymptotic interaction of flocking particles and an incompressible viscous fluid

    International Nuclear Information System (INIS)

    Bae, Hyeong-Ohk; Choi, Young-Pil; Ha, Seung-Yeal; Kang, Moon-Jin

    2012-01-01

    We present a new coupled kinetic-fluid model for the interactions between Cucker–Smale (C–S) flocking particles and incompressible fluid on the periodic spatial domain T d . Our coupled system consists of the kinetic C–S equation and the incompressible Navier–Stokes equations, and these two systems are coupled through the drag force. For the proposed model, we provide a global existence of weak solutions and a priori time-asymptotic exponential flocking estimates for any smooth flow, when the kinematic viscosity of the fluid is sufficiently large. The velocity of individual C–S particles and fluid velocity tend to the averaged time-dependent particle velocities exponentially fast

  14. Sand intake by laying hens and its effect on egg production parameters

    NARCIS (Netherlands)

    Meulen, van der J.; Kwakernaak, C.; Kan, C.A.

    2008-01-01

    Soil intake may be the most prominent source of environmental contaminants for free range and organic hens, but there are no quantitative data concerning soil intake by domestic hens. Consumption of soil of 14¿32 g a day can be estimated from literature, but such a dilution of nutrient intake seems

  15. Henning Witte : Estonia-film tuleb / Villem Valme

    Index Scriptorium Estoniae

    Valme, Villem, 1977-

    2000-01-01

    Kavandatavast katastrooffilmist "Baltic Storm", mis on ajendatud väidetest, et "Estonia" uppus maffiavandenõu tõttu. Stsenaristideks on Juta Rabe, Henning Witte ja Kaj Holmberg. Ka : Nädal nr. 47, lk. 5

  16. Fore-aft asymmetric flocking

    Science.gov (United States)

    Chen, Qiu-shi; Patelli, Aurelio; Chaté, Hugues; Ma, Yu-qiang; Shi, Xia-qing

    2017-08-01

    We show that fore-aft asymmetry, a generic feature of living organisms and some active matter systems, can have a strong influence on the collective properties of even the simplest flocking models. Specifically, an arbitrarily weak asymmetry favoring front neighbors changes qualitatively the phase diagram of the Vicsek model. A region where many sharp traveling band solutions coexist is present at low noise strength, below the Toner-Tu liquid, at odds with the phase-separation scenario well describing the usual isotropic model. Inside this region, a "banded-liquid" phase with algebraic density distribution coexists with band solutions. Linear stability analysis at the hydrodynamic level suggests that these results are generic and not specific to the Vicsek model.

  17. The Effect of Cooled Perches on Immunological Parameters of Caged White Leghorn Hens during the Hot Summer Months.

    Directory of Open Access Journals (Sweden)

    Rebecca A Strong

    Full Text Available The objective of this study was to determine if thermally cooled perches improve hen immunity during hot summer. White Leghorn pullets at 16 week of age were randomly assigned to 18 cages of 3 banks at 9 hens per cage. Each bank was assigned to 1 of the 3 treatments up to 32 week of age: 1 thermally cooled perches, 2 perches with ambient air, and 3 cages without perches. Hens were exposed to natural ambient temperatures from June through September 2013 in Indiana with a 4 h acute heat episode at 27.6 week of age. The packed cell volume, heterophil to lymphocyte (H/L ratio, plasma concentrations of total IgG, and cytokines of interleukin-1β and interleukin-6, plus lipopolysaccharide-induced tumor necrosis factor-α factor were measured at both 27.6 and 32 week of age. The mRNA expressions of these cytokines, toll-like receptor-4, and inducible nitric oxide synthase were also examined in the spleen of 32 week-old hens. Except for H/L ratio, thermally cooled perches did not significantly improve currently measured immunological indicators. These results indicated that the ambient temperature of 2013 summer in Indiana (24°C, 17.1 to 33.1°C was not high enough and the 4 h heat episode at 33.3°C (32 to 34.6°C was insufficient in length to evoke severe heat stress in hens. However, cooled perch hens had a lower H/L ratio than both air perch hens and control hens at 27.6 week of age and it was still lower compared to control hens (P < 0.05, respectively at 32 week of age. The lowered H/L ratio of cooled perch hens may suggest that they were able to cope with acute heat stress more effectively than control hens. Further studies are needed to evaluate the effectiveness of thermally cooled perches on hen health under higher ambient temperatures.

  18. Investigation of the metabolism of colostomized laying hens with 15N-labelled wheat. 6

    International Nuclear Information System (INIS)

    Gruhn, K.; Hennig, A.

    1980-01-01

    Three colostomized laving hens received 40 g 15 N-labelled wheat with 20.13 atom-% 15 N excess ( 15 N'), 19.18 atom-% 15 N'-lysine, 18.17 atom-% 15 N'-histidine and 20.43 atom-% 15 N'-arginine per day over a period of four days. After having received the same non-labelled feed ration on the following four days, the hens were slaughtered. The incorporation and distribution of 15 N' in the total nitrogen and the nitrogen of the basic amino acids was determined in liver, kidneys, muscles, bones and the remaining carcass (excluding blood, digestive tract and genital organs). The quota of nitrogen of natural isotope frequency ( 14 N) of the total 14 N of the hens' carcasses was 47% in the muscles, 14% in the bones and 20% in the feathers; the relative 15 N' values were 37%, 8% and 1%, resp. The atom-% 15 N' in the kidneys was twice as much as in the liver four days after the last 15 N' application. The average percentage of the nitrogen in the three basic amino acids of the total nitrogen in the tissues and organs (excluding feathers) is 25% concerning both 14 N and 15 N'. The 15N' balance revealed that in hen 1 100%, in hen 2 102% and in hen 3 101% of the consumed wheat 15 N' were found. (author)

  19. Pathogen Prevalence From Traditional Cage and Free Range Production

    Science.gov (United States)

    Overview: A study was conducted to determine if differences in pathogen prevalence occurred between a sister flock of conventional cage and free range laying hens. Both environmental and egg microbiology was monitored throughout 20 – 79 weeks of age. Salmonella, Campylobacter, and Listeria preval...

  20. Comparison of two different breeding systems laying hens in relation to egg damage and dirty, I

    Directory of Open Access Journals (Sweden)

    Mária Angelovičová

    2014-11-01

    Full Text Available The aim of work was to follow up and statistically evaluate the damage and dirty eggs and egg weight, depending on two different breeding systems and different ages of laying hens. Object of investigation were table eggs, their damage and dirty in the laying hens of the final hybrid ISA Brown reared in enriched cage system, and the free range system.  In both rearing systems were ensured the conditions for laying hens in accordance with legislation establishing minimum standards for the laying hens minimum standards for the protection of laying hens, protection of animals kept for farming purposes in accordance with the principles of the so-called five freedoms. That was used to feed a complete feed mixture HYD 10 in both breeding systems. The feeders were supplemented with feed by hand every day and the same day were supplemented water to drinking troughs.  Egg collection was hand in both breeding systems. This paper is a contribution to the solution of optimal breeding hens and production of high quality and safe of table eggs. Based on the results was formulated conclusion, which shows that to the damage and dirty eggs are not affected by the age of the breeding system and age of laying hens. Statistically significant difference     (p ≤ 0.05 in the egg weight was observed between breeding cage system and breeding free range system and   between age 30 and 40 weeks of laying hens.

  1. Calculations of long-range three-body interactions for He(n0λS )-He(n0λS )-He(n0'λL )

    Science.gov (United States)

    Yan, Pei-Gen; Tang, Li-Yan; Yan, Zong-Chao; Babb, James F.

    2018-04-01

    We theoretically investigate long-range interactions between an excited L -state He atom and two identical S -state He atoms for the cases of the three atoms all in spin-singlet states or all in spin-triplet states, denoted by He(n0λS )-He(n0λS )-He(n0'λL ), with n0 and n0' principal quantum numbers, λ =1 or 3 the spin multiplicity, and L the orbital angular momentum of a He atom. Using degenerate perturbation theory for the energies up to second-order, we evaluate the coefficients C3 of the first-order dipolar interactions and the coefficients C6 and C8 of the second-order additive and nonadditive interactions. Both the dipolar and dispersion interaction coefficients, for these three-body degenerate systems, show dependences on the geometrical configurations of the three atoms. The nonadditive interactions start to appear in second-order. To demonstrate the results and for applications, the obtained coefficients Cn are evaluated with highly accurate variationally generated nonrelativistic wave functions in Hylleraas coordinates for He(1 1S ) -He(1 1S ) -He(2 1S ) , He(1 1S ) -He(1 1S ) -He(2 1P ) , He(2 1S ) -He(2 1S ) -He(2 1P ) , and He(2 3S ) -He(2 3S ) -He(2 3P ) . The calculations are given for three like nuclei for the cases of hypothetical infinite mass He nuclei, and of real finite mass 4He or 3He nuclei. The special cases of the three atoms in equilateral triangle configurations are explored in detail, and for the cases in which one of the atoms is in a P state, we also present results for the atoms in an isosceles right triangle configuration or in an equally spaced collinear configuration. The results can be applied to construct potential energy surfaces for three helium atom systems.

  2. Deposition of melamine in eggs from laying hens exposed to melamine contaminated feed.

    Science.gov (United States)

    Chen, Yiqiang; Yang, Wenjun; Wang, Zongyi; Peng, Yong; Li, Bin; Zhang, Liying; Gong, Limin

    2010-03-24

    The deposition profile of melamine was studied in eggs obtained from laying hens fed melamine contaminated feed. A total of 180 laying hens were divided into five groups and were fed diets spiked with 0, 5, 25, 50, or 100 mg of melamine per kg of feed. Eggs collected on days 1, 3, 5, 7, 9, 11, 13, and 15 were analyzed by a gas chromatography-mass spectrometry method, which was fully validated for melamine analysis prior to use. For each treatment group, the melamine level in the eggs was similar from day 1 to day 15 (P > 0.05), suggesting that laying hens did not accumulate melamine for later deposition in eggs. The average melamine concentrations in eggs were 0.00 (below limit of detection), 0.16, 0.47, 0.84, and 1.48 mg/kg for the 0, 5, 25, 50, and 100 mg/kg treatment groups, respectively, which demonstrated an apparent dose-response relationship, and a safety threshold of 164 mg/kg melamine in the feed of laying hen was estimated when a maximum tolerance level of 2.5 mg/kg melamine in egg was adopted. These results provide a scientific basis for the risk assessment of melamine in feeds fed to laying hens.

  3. Habitat selection of Merriam's turkey (Meleagris gallopavo Merriami) hens with poults in the Black Hills, South Dakota

    Science.gov (United States)

    Mark A. Rumble; Stanley H. Anderson

    1993-01-01

    We studied habitat selection patterns of Merriam's Turkey (Meleagris gallopavo merriami) hens with poults in a ponderosa pine (Pinus ponderosa) ecosystem. Thirty-six radio-marked hens produced 19 broods, and we obtained 230 locations of hens with poults. We described vegetation of habitats using criteria from the Rocky...

  4. A method for hardening or curing adhesives for flocking thermally sensitive substrata by means of an electron-beam

    International Nuclear Information System (INIS)

    Nablo, S.V.; Fussa, A.D.

    1975-01-01

    The invention relates to a method for hardening or curing adhesives for flocking thermally sensitive substrata by means of an electron-beam. That method consists in accurately adjusting the parameters of irradiation by an electron-beam and the beam velocity so as to obtain, a very rapid hardening of adhesives used for fixing flocking materials, or the like, to thermally sensitive substrate. That can be applied to hardening or curing adhesives for flocking thermally-sensitive substrata which normally restrict the hardening rate [fr

  5. Cooled perch effects on performance and well-being traits in caged White Leghorn hens.

    Science.gov (United States)

    Hu, J Y; Hester, P Y; Makagon, M M; Vezzoli, G; Gates, R S; Xiong, Y J; Cheng, H W

    2016-12-01

    We assessed the effects of chilled water cooling perches on hen performance and physiological and behavioral parameters under "natural" high temperatures during the 2013 summer with a 4-hour acute heating episode. White Leghorns at 16 wk of age (N = 162) were randomly assigned to 18 cages (n = 9) arranged into 3 units. Each unit was assigned to one of the 3 treatments through 32 wk of age: 1) cooled perches, 2) air perches, and 3) no perches. Chilled water (10°C) was circulated through the cooled perches when cage ambient temperature exceeded 25°C. At the age of 27.6 wk, hens were subjected to a 4-hour acute heating episode of 33.3°C and plasma corticosterone was determined within 2 hours. Egg production was recorded daily. Feed intake and egg and shell quality were measured at 5-week intervals. Feather condition, foot health, adrenal and liver weights, plasma corticosterone, and heat shock protein 70 mRNA were determined at the end of the study at 32 wk of age. The proportion of hens per cage perching, feeding, drinking, panting, and wing spreading was evaluated over one d every 5 wks and on the d of acute heat stress. There were no treatment effects on the measured physiological and production traits except for nail length. Nails were shorter for cooled perch hens than control (P = 0.002) but not air perch hens. Panting and wing spread were observed only on the day of acute heat stress. The onset of both behaviors was delayed for cooled perch hens, and they perched more than air perch hens following acute heat stress (P = 0.001) and at the age 21.4 wk (P = 0.023). Cooled perch hens drank less than control (P = 0.019) but not air perch hens at the age 21.4 wk. These results indicate that thermally cooled perches reduced thermoregulatory behaviors during acute heat stress, but did not affect their performance and physiological parameters under the ambient temperature imposed during this study. Published by Oxford University Press on behalf of

  6. Limited Associations between Keel Bone Damage and Bone Properties Measured with Computer Tomography, Three-Point Bending Test, and Analysis of Minerals in Swiss Laying Hens

    Directory of Open Access Journals (Sweden)

    Sabine G. Gebhardt-Henrich

    2017-08-01

    Full Text Available Keel bone damage is a wide-spread welfare problem in laying hens. It is unclear so far whether bone quality relates to keel bone damage. The goal of the present study was to detect possible associations between keel bone damage and bone properties of intact and damaged keel bones and of tibias in end-of-lay hens raised in loose housing systems. Bones were palpated and examined by peripheral quantitative computer tomography (PQCT, a three-point bending test, and analyses of bone ash. Contrary to our expectations, PQCT revealed higher cortical and trabecular contents in fractured than in intact keel bones. This might be due to structural bone repair after fractures. Density measurements of cortical and trabecular tissues of keel bones did not differ between individuals with and without fractures. In the three-point bending test of the tibias, ultimate shear strength was significantly higher in birds with intact vs. fractured keel bones. Likewise, birds with intact or slightly deviated keel bones had higher mineral and calcium contents of the keel bone than birds with fractured keel bones. Calcium content in keel bones was correlated with calcium content in tibias. Although there were some associations between bone traits related to bone strength and keel bone damage, other factors such as stochastic events related to housing such as falls and collisions seem to be at least as important for the prevalence of keel bone damage.

  7. Chronic interstitial lung disease in nylon flocking industry workers--Rhode Island, 1992-1996.

    Science.gov (United States)

    1997-09-26

    Interstitial lung disease (ILD) occurs infrequently; some cases are attributed to sarcoidosis, pulmonary hemorrhage syndromes, connective tissue diseases, hypersensitivity pneumonitis, drugs, radiation, and mineral dusts (e.g., silica or asbestos). However, most cases of ILD are of uncertain classification or etiology. This report describes preliminary findings of the investigation in Rhode Island of an outbreak of ILD among workers involved in the manufacture of finely cut nylon (flock) and flocked fabric (used for upholstery, clothing, and automobiles); the findings provide evidence of a newly recognized occupational illness.

  8. Bidirectional sorting of flocking particles in the presence of asymmetric barriers.

    Science.gov (United States)

    Drocco, Jeffrey A; Olson Reichhardt, C J; Reichhardt, C

    2012-05-01

    We demonstrate numerically bidirectional sorting of flocking particles interacting with an array of V-shaped asymmetric barriers. Each particle aligns with the average swimming direction of its neighbors according to the Vicsek model and experiences additional steric interactions as well as repulsion from the fixed barriers. We show that particles preferentially localize to one side of the barrier array over time and that the direction of this rectification can be reversed by adjusting the particle-particle exclusion radius or the noise term in the equations of motion. These results provide a conceptual basis for isolation and sorting of single-cell and multicellular organisms that move collectively according to flocking-type interaction rules.

  9. Molecular phylogenetics and comparative modeling of HEN1, a methyltransferase involved in plant microRNA biogenesis

    Directory of Open Access Journals (Sweden)

    Obarska Agnieszka

    2006-01-01

    Full Text Available Abstract Background Recently, HEN1 protein from Arabidopsis thaliana was discovered as an essential enzyme in plant microRNA (miRNA biogenesis. HEN1 transfers a methyl group from S-adenosylmethionine to the 2'-OH or 3'-OH group of the last nucleotide of miRNA/miRNA* duplexes produced by the nuclease Dicer. Previously it was found that HEN1 possesses a Rossmann-fold methyltransferase (RFM domain and a long N-terminal extension including a putative double-stranded RNA-binding motif (DSRM. However, little is known about the details of the structure and the mechanism of action of this enzyme, and about its phylogenetic origin. Results Extensive database searches were carried out to identify orthologs and close paralogs of HEN1. Based on the multiple sequence alignment a phylogenetic tree of the HEN1 family was constructed. The fold-recognition approach was used to identify related methyltransferases with experimentally solved structures and to guide the homology modeling of the HEN1 catalytic domain. Additionally, we identified a La-like predicted RNA binding domain located C-terminally to the DSRM domain and a domain with a peptide prolyl cis/trans isomerase (PPIase fold, but without the conserved PPIase active site, located N-terminally to the catalytic domain. Conclusion The bioinformatics analysis revealed that the catalytic domain of HEN1 is not closely related to any known RNA:2'-OH methyltransferases (e.g. to the RrmJ/fibrillarin superfamily, but rather to small-molecule methyltransferases. The structural model was used as a platform to identify the putative active site and substrate-binding residues of HEN and to propose its mechanism of action.

  10. Prediction of the metabolizable energy requirements of free-range laying hens.

    Science.gov (United States)

    Brainer, M M A; Rabello, C B V; Santos, M J B; Lopes, C C; Ludke, J V; Silva, J H V; Lima, R A

    2016-01-01

    This experiment was conducted with the aim of estimating the ME requirements of free-range laying hens for maintenance, weight gain, and egg production. These experiments were performed to develop an energy requirement prediction equation by using the comparative slaughter technique and the total excreta collection method. Regression equations were used to relate the energy intake, the energy retained in the body and eggs, and the heat production of the hens. These relationships were used to determine the daily ME requirement for maintenance, the efficiency energy utilization above the requirements for maintenance, and the NE requirement for maintenance. The requirement for weight gain was estimated from the energy content of the carcass, and the diet's efficiency energy utilization was determined from the weight gain, which was measured during weekly slaughter. The requirement for egg production was estimated by considering the energy content of the eggs and the efficiency of energy deposition in the eggs. The requirement and efficiency energy utilization for maintenance were 121.8 kcal ME/(kg∙d)and 0.68, respectively. Similarly, the NE requirement for maintenance was 82.4 kcal ME/(kg∙d), and the efficiency energy utilization above maintenance was 0.61. Because the carcass body weight and energy did not increase during the trial, the weight gain could not be estimated. The requirements for egg production requirement and efficiency energy utilization for egg production were 2.48 kcal/g and 0.61, respectively. The following energy prediction equation for free-range laying hens (without weight gain) was developed: ME /(hen ∙ d) = 121.8 × W + 2.48 × EM, in which W = body weight (kg) and EM = egg mass (g/[hen ∙ d]).

  11. Broiler health status has a major negative impact on broiler flock contamination with Campylobacter spp. in Lithuania

    DEFF Research Database (Denmark)

    Legaudaite-Lydekaitiene, Viktorija; Serniene, Loreta; Vismantaite, Vaida

    2017-01-01

    analysed using the statistical package SPSS. Study revealed that 59.3% of the examined broiler flocks were contaminated with Campylobacter spp. Statistical analysis revealed that broiler flock contamination with Campylobacter was abattoir- and farm-dependent. Among a number of risk factors (e.g. the number...

  12. Outer membrane vesicles of Gallibacterium anatis induce protective immunity in egg-laying hens.

    Science.gov (United States)

    Pors, Susanne E; Pedersen, Ida J; Skjerning, Ragnhild Bager; Thøfner, Ida C N; Persson, Gry; Bojesen, Anders M

    2016-11-15

    Gallibacterium anatis causes infections in the reproductive tract of egg-laying hens and induce increased mortality and decreased egg production. New prophylactic measures are needed in order to improve animal welfare and production efficiency. Bacterial outer membrane vesicles (OMVs) have previously shown promising results in protection against infections and we hypothesized that OMVs could serve as an immunogen to protect egg-laying hens against G. anatis. To investigate the immunogenic potential of G. anatis OMVs, two in vivo studies in egg-laying hens were made. The trials assessedthe degree of protection provided by immunization with G. anatis OMV against challenge and the IgY responses in serum after immunization and challenge, respectively. A total of 64 egg-laying hens were included in the trials. OMVs for immunization were produced and purified from a high-producing G. anatis ΔtolR mutant. Challenge was done with G. anatis 12656-12 and evaluated by scoring lesions and bacterial re-isolation rates from peritoneum. Finally, levels of OMV-specific IgY in sera were assayed by ELISA. Immunization with OMVs decreased the lesions scores significantly, while the bacterial re-isolation remained unchanged. Furthermore, a high OMV-specific IgY response was induced by immunization and subsequent challenge of the hens. The results strongly indicate that immunization with G. anatis OMVs provides significant protection against G. anatis challenge and induces specific antibody responses with high titers of OMV-specific IgY in serum. The results therefore show great promise for OMV based vaccines aiming at providing protecting against G. anatis in egg-laying hens. Copyright © 2016 Elsevier B.V. All rights reserved.

  13. The Influence of Keel Bone Damage on Welfare of Laying Hens

    DEFF Research Database (Denmark)

    Riber, Anja Brinch; Casey-Trott, Teresa M.; Herskin, Mette S.

    2018-01-01

    This article reviews current knowledge about welfare implications of keel bone damage in laying hens. As an initial part, we shortly describe the different conditions and present major risk factors as well as findings on the prevalence of the conditions. Keel bone damage is found in all types...... of commercial production, however with varying prevalence across systems, countries, and age of the hens. In general, the understanding of animal welfare is influenced by value-based ideas about what is important or desirable for animals to have a good life. This review covers different types of welfare...... indicators, including measures of affective states, basic health, and functioning as well as natural living of the birds, thereby including the typical public welfare concerns. Laying hens with keel bone fractures show marked behavioral differences in highly motivated behavior, such as perching, nest use...

  14. Chlorinated drinking water for lightweight laying hens

    Directory of Open Access Journals (Sweden)

    A.F. Schneider

    Full Text Available ABSTRACT The study aimed to evaluate the effect of different levels of chlorine in drinking water of laying hens on zootechnical performance, eggs shell quality, hemogasometry levels and calcium content in tibia. 144 Hy-Line laying hens, 61 weeks old, were used distributed in 24 metabolism cages. They were subjected to water diets, for a period of 28 days, using sodium hypochlorite as a chlorine source in order to obtain the following concentrations: 5ppm (control, 20ppm, 50ppm, and 100ppm. Their performance was evaluated through water consumption, feed intake, egg production and weight, egg mass, feed conversion. Shell quality was measured by specific gravity. At the end of the experiment, arterial blood was collected for blood gas level assessment and a poultry of each replicate was sacrificed to obtain tibia and calcium content measurement. There was a water consumption reduction from 20ppm of chlorine and feed intake reduction in poultry receiving water with 100ppm of chlorine. The regression analysis showed that the higher the level of chlorine in water, the higher the reduction in consumption. There were no differences in egg production and weight, egg mass, feed conversion, specific gravity, tibia calcium content, and hemogasometry levels (hydrogenionic potential, carbon dioxide partial pressure, oxygen partial pressure, sodium, potassium, chloride, bicarbonate, carbon dioxide total concentration, anion gap and oxygen saturation. The use of levels above 5ppm of chlorine is not recommended in the water of lightweight laying hens.

  15. Validation of the effects of small differences in dietary metabolizable energy and feed restriction in first-cycle laying hens.

    Science.gov (United States)

    Murugesan, G R; Persia, M E

    2013-05-01

    An experiment was conducted to evaluate energy utilization of laying hens fed diets containing 2 ME concentrations, using response criteria including performance, BW, abdominal fat pad, and energy digestibility. The experiment was a 2 × 2 factorial with 2 feeding regimens (ad libitum and restriction fed), and 2 dietary ME levels [2,880 kcal/kg of ME (CON); and 2,790 kcal/kg of ME (LME)]. A total of 60 Hy-Line W36 first-cycle laying hens were fed experimental diets, resulting in 15 individually caged hens for each of the 4 treatments. Hens in the restriction-fed group were fed 90 g of feed per day. The CON diet was formulated to meet or exceed the NRC (1994) recommendations with 2,880 kcal/kg, whereas the LME diet was similar with the exception of a 90 kcal/kg reduction in ME. Hens were fed experimental diets for 12 wk from hen 28 to 39 wk of age. Hen day egg production, weekly feed intake, and every 2 wk, egg weights and egg mass were recorded, whereas hen BW was measured every 4 wk. Excreta samples were collected over the last 5 d of experiment to determine AMEn. Abdominal fat pads were measured individually for all hens at the end of experiment. There were no interactions between feeding regimens and dietary ME levels throughout the experiment. Feed restriction resulted in reductions (P ≤ 0.01) in hen day egg production, BW, and abdominal fat pad, indicating reduced nutrient availability to partition toward production, maintenance, and storage functions. The reduction in energy intake between CON and LME fed birds (90 kcal/kg) did not change the energy partitioned toward production or maintenance, but reduced (P = 0.03) the energy stored (reduced fat pad) of LME-fed hens. These results suggest that energy is used following the pattern of production and maintenance before storage requirements and that fat pad (energy storage) may be the most sensitive indicator of dietary energy status over short-term in Hy-Line W36 laying hens.

  16. FLOCK cluster analysis of mast cell event clustering by high-sensitivity flow cytometry predicts systemic mastocytosis.

    Science.gov (United States)

    Dorfman, David M; LaPlante, Charlotte D; Pozdnyakova, Olga; Li, Betty

    2015-11-01

    In our high-sensitivity flow cytometric approach for systemic mastocytosis (SM), we identified mast cell event clustering as a new diagnostic criterion for the disease. To objectively characterize mast cell gated event distributions, we performed cluster analysis using FLOCK, a computational approach to identify cell subsets in multidimensional flow cytometry data in an unbiased, automated fashion. FLOCK identified discrete mast cell populations in most cases of SM (56/75 [75%]) but only a minority of non-SM cases (17/124 [14%]). FLOCK-identified mast cell populations accounted for 2.46% of total cells on average in SM cases and 0.09% of total cells on average in non-SM cases (P < .0001) and were predictive of SM, with a sensitivity of 75%, a specificity of 86%, a positive predictive value of 76%, and a negative predictive value of 85%. FLOCK analysis provides useful diagnostic information for evaluating patients with suspected SM, and may be useful for the analysis of other hematopoietic neoplasms. Copyright© by the American Society for Clinical Pathology.

  17. Immune response of laying hens exposed to 30 ppm ammonia for 25 weeks

    Science.gov (United States)

    Ammonia is one of the most prominent aerial pollutants inside poultry production facilities, affecting chicken health and well-being based on its levels and exposure durations. The aim of this study was to investigate the effect of 30 ppm ammonia on the immune response of laying hens. Hens at 18 wk ...

  18. Effects of habitat and time of day on flock size of Turkey Vultures in Cuba (Cathartes aura

    Directory of Open Access Journals (Sweden)

    Piotr Tryjanowski

    2018-01-01

    Full Text Available In agricultural landscapes, the Turkey Vulture Cathartes aura feeds mainly on carcases of domestic animals. In spring 2017, data on 214 flocks of Turkey vultures were collected in a road survey in Cuba (in total 2384 km. Turkey Vultures were found to be common accross Cuba, but flock size varied between habitats, reaching a maximum of 43 in valleys and 31 in agricultural landscapes with domestic animal farms. Vultures were active throughout the day, but the time of day did not significantly affect flock size. This study corroborates previous studies which suggested that carrion resources located in agricultural habitats and river valleys is crucial for the continued survival of this still abundant species. Changes in Cuba’s socio-political system in the near future will likely impact agricultural practices, and this in turn will likely affect Turkey Vultures. Our study may serve as a baseline against which future population changes and flocking behaviour of Turkey Vultures can be compared.

  19. Lycopene Protects Against Spontaneous Ovarian Cancer Formation in Laying Hens.

    Science.gov (United States)

    Sahin, Kazim; Yenice, Engin; Tuzcu, Mehmet; Orhan, Cemal; Mizrak, Cengizhan; Ozercan, Ibrahim H; Sahin, Nurhan; Yilmaz, Bahiddin; Bilir, Birdal; Ozpolat, Bulent; Kucuk, Omer

    2018-03-01

    Dietary intake of lycopene has been associated with a reduced risk of ovarian cancer, suggesting its chemopreventive potential against ovarian carcinogenesis. Lycopene's molecular mechanisms of action in ovarian cancer have not been fully understood. Therefore, in the present study, we investigated the effects of lycopene on the ovarian cancer formation using the laying hen model, a biologically relevant animal model of spontaneous ovarian carcinogenesis due to high incidence rates similar to humans. In this study, a total of 150 laying hens at age of 102 weeks were randomized into groups of 50: a control group (0 mg of lycopene per kg of diet) and two treatment groups (200 mg or 400 mg of lycopene per kg of diet, or ~26 and 52 mg/d/hen, respectively). At the end of 12 months, blood, ovarian tissues and tumors were collected. We observed that lycopene supplementation significantly reduced the overall ovarian tumor incidence ( P Lycopene also significantly decreased the rate of adenocarcinoma, including serous and mucinous subtypes ( P lycopene-fed hens compared to control birds ( P lycopene reduced the expression of NF-κB while increasing the expression of nuclear factor erythroid 2 and its major target protein, heme oxygenase 1. In addition, lycopene supplementation decreased the expression of STAT3 by inducing the protein inhibitor of activated STAT3 expression in the ovarian tissues. Taken together, our findings strongly support the potential of lycopene in the chemoprevention of ovarian cancer through antioxidant and anti-inflammatory mechanisms.

  20. Behavioural repertoire of free-range laying hens indoors and outdoors, and in relation to distance from the shed.

    Science.gov (United States)

    Thuy Diep, A; Larsen, H; Rault, J-L

    2018-04-01

    Access to an outdoor area is believed to allow free-range hens to express a greater behavioural repertoire. However, very little research has been done in this area. We hypothesised that the type and frequency of behaviours would differ between areas that vary in their characteristics and distance from the shed. This preliminary study investigated the behaviour of free-range laying hens in indoor and outdoor areas on one commercial free-range farm, through video recordings and scan sampling of focal hens, with the aim of determining their behavioural repertoire and time budget. While ranging, hens spent most of their time foraging. Indoors, hens preened and rested. Behaviour in the wintergarden showed similarities to both the indoor and outdoor areas, with preening, resting and foraging behaviours. Differences were not in the main behavioural repertoire, but rather in terms of time budget, with access to the range and wintergarden encouraging exploration. There was no difference in the types of behaviours that hens performed in the outdoor range compared with inside the shed, but access to a wintergarden and the outdoor range were favoured by the hens for foraging. © 2018 Australian Veterinary Association.