WorldWideScience

Sample records for hens divergently selected

  1. The preference for high-fiber feed in laying hens divergently selected on feather pecking.

    Science.gov (United States)

    Kalmendal, R; Bessei, W

    2012-08-01

    Earlier studies in laying hens have demonstrated a negative correlation between feather pecking and the dietary fiber content of the feed. However, the factors underlying this relationship are not fully understood. In the present experiment, we hypothesized that birds prone to feather pecking would prefer a diet supplemented with dietary fiber. Thus, the aim was to investigate the voluntary consumption of a wheat-soy control diet (CON) and a diet supplemented with 8% spelt hulls (FIB) on the expense of wheat in 20 individually caged hens selected for high feather pecking (HFP) behavior and 20 individually caged hens selected for low feather pecking (LFP) behavior. The proportional intake of FIB was 0.39 and significantly different from 0.50 (Phens (0.36; Phens had inferior plumage condition (Pfeed intake (Phens plucked more feathers from a simple inanimate feather-pecking model, but the number of feathers being pulled out did not correlate with the proportional intake of FIB. It was concluded that the preference for feed supplemented with spelt hulls was different between hens displaying different feather-pecking behavior. The underlying reason for such a difference needs further investigation.

  2. Fearfulness and feather damage in laying hens divergently selected for high and low feather pecking

    DEFF Research Database (Denmark)

    Rodenburg, T Bas; de Haas, Elske N; Nielsen, Birte Lindstrøm

    2010-01-01

    Feather pecking (FP) remains a major welfare and economic problem in laying hens. FP has been found to be related to other behavioural characteristics, such as fearfulness. There are indications that fearful birds are more likely to develop FP. Furthermore, FP can lead to increased fearfulness...... in the victims. To investigate further the relationship between FP and fearfulness, feather damage and behavioural fear responses were recorded in three White Leghorn lines of laying hens: a line selected for high FP (HFP line), a line selected for low FP (LFP line) and an unselected control line (10th...... in fear responses between the HFP and LFP lines were not found, neither in the TI-test, nor in the HA or NO test. As expected, birds from the HFP line had considerably more feather damage than birds from the LFP line and birds from the unselected control line were intermediate. Cages that withdrew from...

  3. Altered Circulating Levels of Serotonin and Immunological Changes in Laying Hens Divergently Selected for Feather Pecking Behavior

    DEFF Research Database (Denmark)

    Buitenhuis, Albert Johannes; Kjaer, Jørgen B.; Labouriau, Rodrigo

    2006-01-01

    The aim of this study was to investigate the changes in immunological parameters as well as changes with respect to plasma levels of serotonin and tryptophan in lines selected for and against feather pecking (FP) behavior [high FP (HP) line and low FP (LP) line] for 5 generations. The hens from...... response to infectious bursal disease virus vaccination after 1 wk post-vaccination compared with the control and LP lines. The number of white blood cells (P

  4. Chicken lines divergently selected for antibody responses to sheep red blood cells show line-specific differences in sensitivity to immunomodulation by diet. Part I: Humoral parameters

    NARCIS (Netherlands)

    Adriaansen-Tennekes, R.; Vries Reilingh, de G.; Nieuwland, M.G.B.; Parmentier, H.K.; Savelkoul, H.F.J.

    2009-01-01

    Individual differences in nutrient sensitivity have been suggested to be related with differences in stress sensitivity. Here we used layer hens divergently selected for high and low specific antibody responses to SRBC (i.e., low line hens and high line hens), reflecting a genetically based

  5. Variation in selection of microhabitats by Merriam's turkey brood hens

    Science.gov (United States)

    Mark A. Rumble; Stanley H. Anderson

    1997-01-01

    We studied microhabitats of Merriam‘s turkey (Meleagris gallopavo merriami) brood hens in a ponderosa pine (Pinus ponderosa) ecosystem in South Dakota from 1986 to 1988. Cluster analysis indicated three groups of microhabitats, open-shrub, open-grasslforb and forest, based on vegetation characteristics at sites selected by brood...

  6. Serotonin release in the caudal nidopallium of adult laying hens genetically selected for high and low feather pecking behavior: An in vivo microdialysis study

    NARCIS (Netherlands)

    Kops, M.S.; Kjaer, J.B.; Güntürkün, O.; Westphal, K.C.G.; Korte-Bouws, G.A.H.; Olivier, B.; Bolhuis, J.E.; Korte, S.M.

    2014-01-01

    Severe feather pecking (FP) is a detrimental behavior causing welfare problems in laying hens. Divergent genetic selection for FP in White Leghorns resulted in strong differences in FP incidences between lines. More recently, it was shown that the high FP (HFP) birds have increased locomotor

  7. 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.

  8. 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...

  9. 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...

  10. Divergent clonal selection dominates medulloblastoma at recurrence

    Science.gov (United States)

    Morrissy, A. Sorana; Garzia, Livia; Shih, David J. H.; Zuyderduyn, Scott; Huang, Xi; Skowron, Patryk; Remke, Marc; Cavalli, Florence M. G.; Ramaswamy, Vijay; Lindsay, Patricia E.; Jelveh, Salomeh; Donovan, Laura K.; Wang, Xin; Luu, Betty; Zayne, Kory; Li, Yisu; Mayoh, Chelsea; Thiessen, Nina; Mercier, Eloi; Mungall, Karen L.; Ma, Yusanne; Tse, Kane; Zeng, Thomas; Shumansky, Karey; Roth, Andrew J. L.; Shah, Sohrab; Farooq, Hamza; Kijima, Noriyuki; Holgado, Borja L.; Lee, John J. Y.; Matan-Lithwick, Stuart; Liu, Jessica; Mack, Stephen C.; Manno, Alex; Michealraj, K. A.; Nor, Carolina; Peacock, John; Qin, Lei; Reimand, Juri; Rolider, Adi; Thompson, Yuan Y.; Wu, Xiaochong; Pugh, Trevor; Ally, Adrian; Bilenky, Mikhail; Butterfield, Yaron S. N.; Carlsen, Rebecca; Cheng, Young; Chuah, Eric; Corbett, Richard D.; Dhalla, Noreen; He, An; Lee, Darlene; Li, Haiyan I.; Long, William; Mayo, Michael; Plettner, Patrick; Qian, Jenny Q.; Schein, Jacqueline E.; Tam, Angela; Wong, Tina; Birol, Inanc; Zhao, Yongjun; Faria, Claudia C.; Pimentel, José; Nunes, Sofia; Shalaby, Tarek; Grotzer, Michael; Pollack, Ian F.; Hamilton, Ronald L.; Li, Xiao-Nan; Bendel, Anne E.; Fults, Daniel W.; Walter, Andrew W.; Kumabe, Toshihiro; Tominaga, Teiji; Collins, V. Peter; Cho, Yoon-Jae; Hoffman, Caitlin; Lyden, David; Wisoff, Jeffrey H.; Garvin, James H.; Stearns, Duncan S.; Massimi, Luca; Schüller, Ulrich; Sterba, Jaroslav; Zitterbart, Karel; Puget, Stephanie; Ayrault, Olivier; Dunn, Sandra E.; Tirapelli, Daniela P. C.; Carlotti, Carlos G.; Wheeler, Helen; Hallahan, Andrew R.; Ingram, Wendy; MacDonald, Tobey J.; Olson, Jeffrey J.; Van Meir, Erwin G.; Lee, Ji-Yeoun; Wang, Kyu-Chang; Kim, Seung-Ki; Cho, Byung-Kyu; Pietsch, Torsten; Fleischhack, Gudrun; Tippelt, Stephan; Ra, Young Shin; Bailey, Simon; Lindsey, Janet C.; Clifford, Steven C.; Eberhart, Charles G.; Cooper, Michael K.; Packer, Roger J.; Massimino, Maura; Garre, Maria Luisa; Bartels, Ute; Tabori, Uri; Hawkins, Cynthia E.; Dirks, Peter; Bouffet, Eric; Rutka, James T.; Wechsler-Reya, Robert J.; Weiss, William A.; Collier, Lara S.; Dupuy, Adam J.; Korshunov, Andrey; Jones, David T. W.; Kool, Marcel; Northcott, Paul A.; Pfister, Stefan M.; Largaespada, David A.; Mungall, Andrew J.; Moore, Richard A.; Jabado, Nada; Bader, Gary D.; Jones, Steven J. M.; Malkin, David; Marra, Marco A.; Taylor, Michael D.

    2016-01-01

    The development of targeted anti-cancer therapies through the study of cancer genomes is intended to increase survival rates and decrease treatment-related toxicity. We treated a transposon–driven, functional genomic mouse model of medulloblastoma with ‘humanized’ in vivo therapy (microneurosurgical tumour resection followed by multi-fractionated, image-guided radiotherapy). Genetic events in recurrent murine medulloblastoma exhibit a very poor overlap with those in matched murine diagnostic samples (sequencing of 33 pairs of human diagnostic and post-therapy medulloblastomas demonstrated substantial genetic divergence of the dominant clone after therapy (recurrence). In both mice and humans, the dominant clone at recurrence arose through clonal selection of a pre-existing minor clone present at diagnosis. Targeted therapy is unlikely to be effective in the absence of the target, therefore our results offer a simple, proximal, and remediable explanation for the failure of prior clinical trials of targeted therapy. PMID:26760213

  11. Variance components and selection response for feather-pecking behavior in laying hens.

    Science.gov (United States)

    Su, G; Kjaer, J B; Sørensen, P

    2005-01-01

    Variance components and selection response for feather pecking behavior were studied by analyzing the data from a divergent selection experiment. An investigation indicated that a Box-Cox transformation with power lambda = -0.2 made the data approximately normally distributed and gave the best fit for the model. Variance components and selection response were estimated using Bayesian analysis with Gibbs sampling technique. The total variation was rather large for the investigated traits in both the low feather-pecking line (LP) and the high feather-pecking line (HP). Based on the mean of marginal posterior distribution, in the Box-Cox transformed scale, heritability for number of feather pecking bouts (FP bouts) was 0.174 in line LP and 0.139 in line HP. For number of feather-pecking pecks (FP pecks), heritability was 0.139 in line LP and 0.105 in line HP. No full-sib group effect and observation pen effect were found in the 2 traits. After 4 generations of selection, the total response for number of FP bouts in the transformed scale was 58 and 74% of the mean of the first generation in line LP and line HP, respectively. The total response for number of FP pecks was 47 and 46% of the mean of the first generation in line LP and line HP, respectively. The variance components and the realized selection response together suggest that genetic selection can be effective in minimizing FP behavior. This would be expected to reduce one of the major welfare problems in laying hens.

  12. Long term selection for reduced or increased pecking behaviour in laying hens

    DEFF Research Database (Denmark)

    Buitenhuis, A J; Kjaer, J B

    2008-01-01

    Feather pecking in laying hens is an important issue in animal welfare. Four studies in laying hens were selected which investigated increased or reduced pecking behaviour using direct or indirect measures of feather pecking behaviour. Direct comparison of the selected experiments is difficult......, as the selection criteria and even the selection procedures varied. Keeping these differences in mind, the results of the experiments showed that a) It is possible to change pecking behaviour in the desired direction using selection, b) Aggressive pecking is not related to feather pecking, c) There is no clear...... that dopamine also plays a role in the regulation of pecking behaviour, and finally e) There are differences between the selected lines and their control lines with regard to the immune parameters both in the individual selected lines as the group selected lines, indicating that direct as well as indirect...

  13. The effects of selection on low mortality and brooding by a mother hen on open-field response, feather pecking and cannibalism in laying hens

    NARCIS (Netherlands)

    Rodenburg, T.B.; Uitdehaag, K.A.; Ellen, E.D.; Komen, J.

    2009-01-01

    The aim of the present study was to investigate the effects of selection on low mortality in combination with brooding by a mother hen on open-field response at 5-6 weeks of age and on plumage and body condition at 42 weeks of age. Birds in the experiment were either selected for low mortality in

  14. Effect of a plant preparation Citrosept on selected immunity indices in blood of slaughter turkey hens

    Directory of Open Access Journals (Sweden)

    Elzbieta Rusinek-Prystupa

    2014-09-01

    Full Text Available [b]Introduction and objective[/b]. The objective of this study was to determine the effect of per os administration of 3 various dosages of a Citrosept preparation (a grapefruit extractto growing turkey hens on changes in their selected haematological and immunological blood indices. An attempt was also undertaken to select the most efficient dose of the preparation with respect to the mentioned indices in turkey hens. [b]Materials and methods[/b]. The experiment was conducted on 180 turkey hens allocated at random to 4 groups, 45 birds in each group. Samples of their full blood were analyzed for haematological indices, such as red blood cell count (RBS, haemoglobin content (Hb, haematocrit value (Ht, and white blood cell count (WBC. Samples of blood plasma were assayed to determine the activity of lysozyme (chamber-diffusive method and heterophils capability to reduce nitro blue tetrazolium (stimulated and spontaneous NBT test. Phagocytic activity of leucocytes against Staphylococcus aureus 209P strain was assessed and expressed as the percentage of phagocytic cells (% PC and phagocytic index (PI. [b]Results[/b]. The administration of the grapefruit extract to turkey hens with drinking water caused a significant increase in haemoglobin content in blood, as well as an increase in non-specific humoral immunity marker (activity of lysozyme and non-specific cellular immunity marker (percentage of phagocytic cells; P ≤ 0.05. [b]Conclusions[/b]. The results obtained enabled the positive evaluation of the advisability of applying the Citrosept preparation in the feeding of turkey hens at the age of 6–9 weeks. Among the doses examined, the most efficient with respect to the stimulation of the non-specific humoral and cellular immunity was the dose of 0.021 ml/kg of body weight.

  15. Effect of a plant preparation Citrosept on selected immunity indices in blood of slaughter turkey hens.

    Science.gov (United States)

    Rusinek-Prystupa, Elzbieta; Tatara, Marcin R

    2014-01-01

    The objective of this study was to determine the effect of per os administration of 3 various dosages of a Citrosept preparation (a grapefruit extract)to growing turkey hens on changes in their selected haematological and immunological blood indices. An attempt was also undertaken to select the most efficient dose of the preparation with respect to the mentioned indices in turkey hens. The experiment was conducted on 180 turkey hens allocated at random to 4 groups, 45 birds in each group. Samples of their full blood were analyzed for haematological indices, such as red blood cell count (RBS), haemoglobin content (Hb), haematocrit value (Ht), and white blood cell count (WBC). Samples of blood plasma were assayed to determine the activity of lysozyme (chamber-diffusive method) and heterophils capability to reduce nitro blue tetrazolium (stimulated and spontaneous NBT test). Phagocytic activity of leucocytes against Staphylococcus aureus 209P strain was assessed and expressed as the percentage of phagocytic cells (% PC) and phagocytic index (PI). The administration of the grapefruit extract to turkey hens with drinking water caused a significant increase in haemoglobin content in blood, as well as an increase in non-specific humoral immunity marker (activity of lysozyme) and non-specific cellular immunity marker (percentage of phagocytic cells; P ≤ 0.05). The results obtained enabled the positive evaluation of the advisability of applying the Citrosept preparation in the feeding of turkey hens at the age of 6-9 weeks. Among the doses examined, the most efficient with respect to the stimulation of the non-specific humoral and cellular immunity was the dose of 0.021 ml/kg of body weight.

  16. Analysis of growth characteristics in short-term divergently selected ...

    African Journals Online (AJOL)

    weeks of age body weight in divergent lines of Japanese quail. Growth curves for both sexes within each selection group resembled the general sigmoid shape of a typical growth curve. Gompertz model curves and the observed growth curves were ...

  17. On the Critical Role of Divergent Selection in Evolvability

    Directory of Open Access Journals (Sweden)

    Joel Lehman

    2016-08-01

    Full Text Available An ambitious goal in evolutionary robotics is to evolve increasingly complex robotic behaviors with minimal human design effort. Reaching this goal requires evolutionary algorithms that can unlock from genetic encodings their latent potential for evolvability. One issue clouding this goal is conceptual confusion about evolvability, which often obscures the aspects of evolvability that are important or desirable. The danger from such confusion is that it may establish unrealistic goals for evolvability that prove unproductive in practice. An important issue separate from conceptual confusion is the common misalignment between selection and evolvability in evolutionary robotics. While more expressive encodings can represent higher-level adaptations (e.g. sexual reproduction or developmental systems that increase long-term evolutionary potential (i.e. evolvability, realizing such potential requires gradients of fitness and evolvability to align. In other words, selection is often a critical factor limiting increasing evolvability. Thus, drawing from a series of recent papers, this article seeks to both (1 clarify and focus the ways in which the term evolvability is used within artificial evolution, and (2 argue for the importance of one type of selection, i.e. divergent selection, for enabling evolvability. The main argument is that there is a fundamental connection between divergent selection and evolvability (on both the individual and population level that does not hold for typical goal-oriented selection. The conclusion is that selection pressure plays a critical role in realizing the potential for evolvability, and that divergent selection in particular provides a principled mechanism for encouraging evolvability in artificial evolution.

  18. 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

  19. VARIANCE COMPONENTS AND SELECTION FOR FEATHER PECKING BEHAVIOR IN LAYING HENS

    OpenAIRE

    Su, Guosheng; Kjaer, Jørgen B.; Sørensen, Poul

    2005-01-01

    Variance components and selection response for feather pecking behaviour were studied by analysing the data from a divergent selection experiment. An investigation show that a Box-Cox transformation with power =-0.2 made the data be approximately normally distributed and fit best by the given model. Variance components and selection response were estimated using Bayesian analysis with Gibbs sampling technique. The total variation was rather large for the two traits in both low feather peckin...

  20. Chicken lines divergently selected for antibody responses to sheep red blood cells show line-specific differences in sensitivity to immunomodulation by diet. Part I: Humoral parameters.

    Science.gov (United States)

    Adriaansen-Tennekes, R; de Vries Reilingh, G; Nieuwland, M G B; Parmentier, H K; Savelkoul, H F J

    2009-09-01

    Individual differences in nutrient sensitivity have been suggested to be related with differences in stress sensitivity. Here we used layer hens divergently selected for high and low specific antibody responses to SRBC (i.e., low line hens and high line hens), reflecting a genetically based differential immune competence. The parental line of these hens was randomly bred as the control line and was used as well. Recently, we showed that these selection lines differ in their stress reactivity; the low line birds show a higher hypothalamic-pituitary-adrenal (HPA) axis reactivity. To examine maternal effects and neonatal nutritional exposure on nutrient sensitivity, we studied 2 subsequent generations. This also created the opportunity to examine egg production in these birds. The 3 lines were fed 2 different nutritionally complete layer feeds for a period of 22 wk in the first generation. The second generation was fed from hatch with the experimental diets. At several time intervals, parameters reflecting humoral immunity were determined such as specific antibody to Newcastle disease and infectious bursal disease vaccines; levels of natural antibodies binding lipopolysaccharide, lipoteichoic acid, and keyhole limpet hemocyanin; and classical and alternative complement activity. The most pronounced dietary-induced effects were found in the low line birds of the first generation: specific antibody titers to Newcastle disease vaccine were significantly elevated by 1 of the 2 diets. In the second generation, significant differences were found in lipoteichoic acid natural antibodies of the control and low line hens. At the end of the observation period of egg parameters, a significant difference in egg weight was found in birds of the high line. Our results suggest that nutritional differences have immunomodulatory effects on innate and adaptive humoral immune parameters in birds with high HPA axis reactivity and affect egg production in birds with low HPA axis reactivity.

  1. Divergência genética entre linhagens de matrizes de corte por meio de análise de agrupamento Genetic divergence in meat-type hens using cluster analysis

    Directory of Open Access Journals (Sweden)

    Marcos Yamaki

    2008-05-01

    Full Text Available Este trabalho foi realizado com o objetivo de avaliar a divergência genética de três linhagens de matrizes de corte do Programa de Melhoramento Genético da UFV. Foram avaliados dados de 270 aves, 90 de cada linhagem, para estudo das características dias para o primeiro ovo (DPPO, taxa de postura da 22ª à 56ª semana (TP, peso médio individual na 32ª (PMI1, 40ª (PMI2, 48ª (PMI3, 56ª (PMI4 e 64ª semanas de idade (PMI5; e peso médio do ovo, obtido pela média da pesagem de três ovos na 32ª (PMO1, 40ª (PMO2, 48ª (PMO3, 56ª (PMO4 e 64ª semanas de idade (PMO5. Para avaliar a divergência, foram utilizados dois métodos: hierárquico do vizinho mais próximo e otimização de Tocher. Pelo método hierárquico do vizinho mais próximo, utilizando-se a distância de Mahalanobis ao quadrado (D² como medida de dissimilaridade, formou-se um único grupo. Pelo método de otimização de Tocher, foram formados dois grupos, comprovando que os dois métodos foram discordantes na avaliação da divergência genética de linhas de aves de corte. As características que apresentaram as contribuições relativas mais expressivas para a divergência foram, respectivamente, PMO1 (25,71%, DDPO (21,76%, PMI4 (17,65% e PMI2 (13,04%.Genetic divergence among three lineages of meat-type hens from the Genetic Breeding Program of the Universidade Federal de Viçosa was evaluated for the following traits: days at first egg (DPPO, egg production rate (TP from 22nd to 56th week, body weight on the 32nd (PMI1, on 40th (PMI2, at 48th (PMI3, at 56th (PMI4 and at the 64th week (PMI5, egg weight on the 32nd (PMO1, on 40th (PMO2, at 48th (PMO3, at 56th (PMO4 and at the 64th week (PMO5. Traits were measured on 270 hens (90 of each lineage and two different methods were used to evaluate genetic divergence. For the single linkage hierarchical method, using the squared Mahalanobis distance (D² as the dissimilarity measure, only one single group was formed. When

  2. Selection is stronger in early-versus-late stages of divergence in a Neotropical livebearing fish.

    Science.gov (United States)

    Ingley, Spencer J; Johnson, Jerald B

    2016-03-01

    How selection acts to drive trait evolution at different stages of divergence is of fundamental importance in our understanding of the origins of biodiversity. Yet, most studies have focused on a single point along an evolutionary trajectory. Here, we provide a case study evaluating the strength of divergent selection acting on life-history traits at early-versus-late stages of divergence in Brachyrhaphis fishes. We find that the difference in selection is stronger in the early-diverged population than the late-diverged population, and that trait differences acquired early are maintained over time. © 2016 The Author(s).

  3. Selection on feather pecking affects response to novelty and foraging behaviour in laying hens

    NARCIS (Netherlands)

    Haas, de E.N.; Nielsen, B.; Rodenburg, T.B.; Buitenhuis, A.J.

    2010-01-01

    Feather pecking (FP) is a major welfare problem in laying hens, influenced by multiple factors. FP is thought to be redirected foraging behaviour, however fearful birds are also known to be more sensitive to develop FP. The relationship between fear-responses, foraging and FP is not well understood,

  4. 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.

  5. Determining the Effect of Natural Selection on Linked Neutral Divergence across Species.

    Science.gov (United States)

    Phung, Tanya N; Huber, Christian D; Lohmueller, Kirk E

    2016-08-01

    A major goal in evolutionary biology is to understand how natural selection has shaped patterns of genetic variation across genomes. Studies in a variety of species have shown that neutral genetic diversity (intra-species differences) has been reduced at sites linked to those under direct selection. However, the effect of linked selection on neutral sequence divergence (inter-species differences) remains ambiguous. While empirical studies have reported correlations between divergence and recombination, which is interpreted as evidence for natural selection reducing linked neutral divergence, theory argues otherwise, especially for species that have diverged long ago. Here we address these outstanding issues by examining whether natural selection can affect divergence between both closely and distantly related species. We show that neutral divergence between closely related species (e.g. human-primate) is negatively correlated with functional content and positively correlated with human recombination rate. We also find that neutral divergence between distantly related species (e.g. human-rodent) is negatively correlated with functional content and positively correlated with estimates of background selection from primates. These patterns persist after accounting for the confounding factors of hypermutable CpG sites, GC content, and biased gene conversion. Coalescent models indicate that even when the contribution of ancestral polymorphism to divergence is small, background selection in the ancestral population can still explain a large proportion of the variance in divergence across the genome, generating the observed correlations. Our findings reveal that, contrary to previous intuition, natural selection can indirectly affect linked neutral divergence between both closely and distantly related species. Though we cannot formally exclude the possibility that the direct effects of purifying selection drive some of these patterns, such a scenario would be possible only

  6. Natural and sexual selection giveth and taketh away reproductive barriers: models of population divergence in guppies.

    Science.gov (United States)

    Labonne, Jacques; Hendry, Andrew P

    2010-07-01

    The standard predictions of ecological speciation might be nuanced by the interaction between natural and sexual selection. We investigated this hypothesis with an individual-based model tailored to the biology of guppies (Poecilia reticulata). We specifically modeled the situation where a high-predation population below a waterfall colonizes a low-predation population above a waterfall. Focusing on the evolution of male color, we confirm that divergent selection causes the appreciable evolution of male color within 20 generations. The rate and magnitude of this divergence were reduced when dispersal rates were high and when female choice did not differ between environments. Adaptive divergence was always coupled to the evolution of two reproductive barriers: viability selection against immigrants and hybrids. Different types of sexual selection, however, led to contrasting results for another potential reproductive barrier: mating success of immigrants. In some cases, the effects of natural and sexual selection offset each other, leading to no overall reproductive isolation despite strong adaptive divergence. Sexual selection acting through female choice can thus strongly modify the effects of divergent natural selection and thereby alter the standard predictions of ecological speciation. We also found that under no circumstances did divergent selection cause appreciable divergence in neutral genetic markers.

  7. Effects of genetic group selection against mortality on behavior and peripheral serotonin in domestic laying hens with trimmed and intact beaks

    NARCIS (Netherlands)

    Bolhuis, J.E.; Ellen, E.D.; Reenen, van C.G.; Groot, de J.; Napel, ten J.; Koopmanschap, R.E.; Vries Reilingh, de G.; Uitdehaag, K.A.; Kemp, B.; Rodenburg, T.B.

    2009-01-01

    Severe feather pecking is a maladaptive behavior in laying hens that may result in cannibalism and ultimately death of the victims. Selection methods in which the genetic effect of an animal on the survival of its group members is taken into account, i.e. `group selection¿, have been shown to be

  8. 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...

  9. Selection from parasites favours immunogenetic diversity but not divergence among locally adapted host populations.

    Science.gov (United States)

    Tobler, M; Plath, M; Riesch, R; Schlupp, I; Grasse, A; Munimanda, G K; Setzer, C; Penn, D J; Moodley, Y

    2014-05-01

    The unprecedented polymorphism in the major histocompatibility complex (MHC) genes is thought to be maintained by balancing selection from parasites. However, do parasites also drive divergence at MHC loci between host populations, or do the effects of balancing selection maintain similarities among populations? We examined MHC variation in populations of the livebearing fish Poecilia mexicana and characterized their parasite communities. Poecilia mexicana populations in the Cueva del Azufre system are locally adapted to darkness and the presence of toxic hydrogen sulphide, representing highly divergent ecotypes or incipient species. Parasite communities differed significantly across populations, and populations with higher parasite loads had higher levels of diversity at class II MHC genes. However, despite different parasite communities, marked divergence in adaptive traits and in neutral genetic markers, we found MHC alleles to be remarkably similar among host populations. Our findings indicate that balancing selection from parasites maintains immunogenetic diversity of hosts, but this process does not promote MHC divergence in this system. On the contrary, we suggest that balancing selection on immunogenetic loci may outweigh divergent selection causing divergence, thereby hindering host divergence and speciation. Our findings support the hypothesis that balancing selection maintains MHC similarities among lineages during and after speciation (trans-species evolution). © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  10. The impact of selection, gene flow and demographic history on heterogeneous genomic divergence: three-spine sticklebacks in divergent environments.

    Science.gov (United States)

    Ferchaud, Anne-Laure; Hansen, Michael M

    2016-01-01

    Heterogeneous genomic divergence between populations may reflect selection, but should also be seen in conjunction with gene flow and drift, particularly population bottlenecks. Marine and freshwater three-spine stickleback (Gasterosteus aculeatus) populations often exhibit different lateral armour plate morphs. Moreover, strikingly parallel genomic footprints across different marine-freshwater population pairs are interpreted as parallel evolution and gene reuse. Nevertheless, in some geographic regions like the North Sea and Baltic Sea, different patterns are observed. Freshwater populations in coastal regions are often dominated by marine morphs, suggesting that gene flow overwhelms selection, and genomic parallelism may also be less pronounced. We used RAD sequencing for analysing 28 888 SNPs in two marine and seven freshwater populations in Denmark, Europe. Freshwater populations represented a variety of environments: river populations accessible to gene flow from marine sticklebacks and large and small isolated lakes with and without fish predators. Sticklebacks in an accessible river environment showed minimal morphological and genomewide divergence from marine populations, supporting the hypothesis of gene flow overriding selection. Allele frequency spectra suggested bottlenecks in all freshwater populations, and particularly two small lake populations. However, genomic footprints ascribed to selection could nevertheless be identified. No genomic regions were consistent freshwater-marine outliers, and parallelism was much lower than in other comparable studies. Two genomic regions previously described to be under divergent selection in freshwater and marine populations were outliers between different freshwater populations. We ascribe these patterns to stronger environmental heterogeneity among freshwater populations in our study as compared to most other studies, although the demographic history involving bottlenecks should also be considered in the

  11. Two generations of selection on restricted best linear unbiased prediction breeding values for income minus feed cost in laying hens.

    Science.gov (United States)

    Hagger, C

    1992-07-01

    Two generations of selection on restricted BLUP breeding values were applied in an experiment with laying hens. Selection had been on phenotype of income minus feed cost (IFC) between 21 and 40 wk of age in the previous five generations. The restriction of no genetic change in egg weight was included in the EBV for power-transformed IFC (i.e., IFCt, with t-values of 3.7 and 3.6 in the two generations, respectively). The experiment consisted of two selection lines plus a randomly bred control of 20 male and 80 female breeders each. Observations on 8,844 survivors to 40 wk were available. Relative to the base population average, the restriction reduced genetic gain in IFC from 4.1 and 3.9% to 2.0 and 2.2% per generation in the two selection lines, respectively. Average EBV for egg weight remained nearly constant after a strong increase in the previous five generations. Rates of genetic gain for egg number, body weight, and feed conversion (feed/egg mass) were not affected significantly. In the seventh generation, a genetic gain in feed conversion of 10.3% relative to the phenotypic mean of the base population was obtained.

  12. Functional divergence caused by ancient positive selection of a Drosophila hybrid incompatibility locus.

    Directory of Open Access Journals (Sweden)

    Daniel A Barbash

    2004-06-01

    Full Text Available Interspecific hybrid lethality and sterility are a consequence of divergent evolution between species and serve to maintain the discrete identities of species. The evolution of hybrid incompatibilities has been described in widely accepted models by Dobzhansky and Muller where lineage-specific functional divergence is the essential characteristic of hybrid incompatibility genes. Experimentally tractable models are required to identify and test candidate hybrid incompatibility genes. Several Drosophila melanogaster genes involved in hybrid incompatibility have been identified but none has yet been shown to have functionally diverged in accordance with the Dobzhansky-Muller model. By introducing transgenic copies of the X-linked Hybrid male rescue (Hmr gene into D. melanogaster from its sibling species D. simulans and D. mauritiana, we demonstrate that Hmr has functionally diverged to cause F1 hybrid incompatibility between these species. Consistent with the Dobzhansky-Muller model, we find that Hmr has diverged extensively in the D. melanogaster lineage, but we also find extensive divergence in the sibling-species lineage. Together, these findings implicate over 13% of the amino acids encoded by Hmr as candidates for causing hybrid incompatibility. The exceptional level of divergence at Hmr cannot be explained by neutral processes because we use phylogenetic methods and population genetic analyses to show that the elevated amino-acid divergence in both lineages is due to positive selection in the distant past-at least one million generations ago. Our findings suggest that multiple substitutions driven by natural selection may be a general phenomenon required to generate hybrid incompatibility alleles.

  13. Positive selection and propeptide repeats promote rapid interspecific divergence of a gastropod sperm protein.

    Science.gov (United States)

    Hellberg, M E; Moy, G W; Vacquier, V D

    2000-03-01

    Male-specific proteins have increasingly been reported as targets of positive selection and are of special interest because of the role they may play in the evolution of reproductive isolation. We report the rapid interspecific divergence of cDNA encoding a major acrosomal protein of unknown function (TMAP) of sperm from five species of teguline gastropods. A mitochondrial DNA clock (calibrated by congeneric species divided by the Isthmus of Panama) estimates that these five species diverged 2-10 MYA. Inferred amino acid sequences reveal a propeptide that has diverged rapidly between species. The mature protein has diverged faster still due to high nonsynonymous substitution rates (> 25 nonsynonymous substitutions per site per 10(9) years). cDNA encoding the mature protein (89-100 residues) shows evidence of positive selection (Dn/Ds > 1) for 4 of 10 pairwise species comparisons. cDNA and predicted secondary-structure comparisons suggest that TMAP is neither orthologous nor paralogous to abalone lysin, and thus marks a second, phylogenetically independent, protein subject to strong positive selection in free-spawning marine gastropods. In addition, an internal repeat in one species (Tegula aureotincta) produces a duplicated cleavage site which results in two alternatively processed mature proteins differing by nine amino acid residues. Such alternative processing may provide a mechanism for introducing novel amino acid sequence variation at the amino-termini of proteins. Highly divergent TMAP N-termini from two other tegulines (Tegula regina and Norrisia norrisii) may have originated by such a mechanism.

  14. Natural selection on MHC IIβ in parapatric lake and stream stickleback: Balancing, divergent, both or neither?

    Science.gov (United States)

    Stutz, William E; Bolnick, Daniel I

    2017-09-01

    Major histocompatibility complex (MHC) genes encode proteins that play a central role in vertebrates' adaptive immunity to parasites. MHC loci are among the most polymorphic in vertebrates' genomes, inspiring many studies to identify evolutionary processes driving MHC polymorphism within populations and divergence between populations. Leading hypotheses include balancing selection favouring rare alleles within populations, and spatially divergent selection. These hypotheses do not always produce diagnosably distinct predictions, causing many studies of MHC to yield inconsistent or ambiguous results. We suggest a novel strategy to distinguish balancing vs. divergent selection on MHC, taking advantage of natural admixture between parapatric populations. With divergent selection, individuals with immigrant alleles will be more infected and less fit because they are susceptible to novel parasites in their new habitat. With balancing selection, individuals with locally rare immigrant alleles will be more fit (less infected). We tested these contrasting predictions using three-spine stickleback from three replicate pairs of parapatric lake and stream habitats. We found numerous positive and negative associations between particular MHC IIβ alleles and particular parasite taxa. A few allele-parasite comparisons supported balancing selection, and others supported divergent selection between habitats. But, there was no overall tendency for fish with immigrant MHC alleles to be more or less heavily infected. Instead, locally rare MHC alleles (not necessarily immigrants) were associated with heavier infections. Our results illustrate the complex relationship between MHC IIβ allelic variation and spatially varying multispecies parasite communities: different hypotheses may be concurrently true for different allele-parasite combinations. © 2017 John Wiley & Sons Ltd.

  15. Island biology and morphological divergence of the Skyros wall lizard Podarcis gaigeae: a combined role for local selection and genetic drift on color morph frequency divergence?

    Directory of Open Access Journals (Sweden)

    Runemark Anna

    2010-09-01

    Full Text Available Abstract Background Patterns of spatial variation in discrete phenotypic traits can be used to draw inferences about the adaptive significance of traits and evolutionary processes, especially when compared to patterns of neutral genetic variation. Population divergence in adaptive traits such as color morphs can be influenced by both local ecology and stochastic factors such as genetic drift or founder events. Here, we use quantitative color measurements of males and females of Skyros wall lizard, Podarcis gaigeae, to demonstrate that this species is polymorphic with respect to throat color, and the morphs form discrete phenotypic clusters with limited overlap between categories. We use divergence in throat color morph frequencies and compare that to neutral genetic variation to infer the evolutionary processes acting on islet- and mainland populations. Results Geographically close islet- and mainland populations of the Skyros wall lizard exhibit strong divergence in throat color morph frequencies. Population variation in throat color morph frequencies between islets was higher than that between mainland populations, and the effective population sizes on the islets were small (Ne:s ST for throat color morph frequencies fell within the neutral FST-distribution estimated from microsatellite markers, and genetic drift could thus not be rejected as an explanation for the pattern. Moreover, for both comparisons among mainland-mainland population pairs and between mainland-islet population pairs, morph frequency divergence was significantly correlated with neutral divergence, further pointing to some role for genetic drift in divergence also at the phenotypic level of throat color morphs. Conclusions Genetic drift could not be rejected as an explanation for the pattern of population divergence in morph frequencies. In spite of an expected stabilising selection, throat color frequencies diverged in the islet populations. These results suggest that

  16. Convergent evolution and divergent selection: lizards at the White Sands ecotone.

    Science.gov (United States)

    Rosenblum, Erica Bree

    2006-01-01

    Ecological transition zones, where organismal phenotypes result from a delicate balance between selection and migration, highlight the interplay of local adaptation and gene flow. Here, I study the response of an entire species assemblage to natural selection across a common ecotone. Three lizard species, distributed along a dramatic environmental gradient in substrate color, display convergent adaptation of blanched coloration on the gypsum dunes of White Sands National Monument. I investigate the role of gene flow in modulating phenotypic response to selection by quantifying color variation and genetic variation across the ecotone. I find species differences in degree of background matching and in genetic connectivity of populations across the ecotone. Differences among species in phenotypic response to selection scale precisely to levels of genetic isolation. Species with higher levels of gene flow across the ecotone exhibit less dramatic responses to selection. Results also reveal a strong signal of ecologically mediated divergence for White Sands lizards. For all species, phenotypic variation is better explained by habitat similarity than genetic similarity. Convergent evolution of blanched coloration at White Sands clearly reflects the action of strong divergent selection; however, adaptive response appears to be modulated by gene flow and demographic history and can be predicted by divergence-with-gene-flow models.

  17. GENETIC DIVERGENCE AND MORPHO - AGRONOMIC PERFORMANCE OF JATROPHA CURCAS L. CLONES FOR SELECTION OF CLONAL VARIETIES

    Directory of Open Access Journals (Sweden)

    ADRIANA QUEIROZ DE ALMEIDA

    2016-01-01

    Full Text Available The knowledge about genetic diversity of jatropha crop is important for genetic conservation resources and breeding of this species. The aim of this study was to evaluate the genetic diversity and performance of jatropha clones through morphological characterization to selection of clonal varieties for biofuels production. The clones were obtained through shoot cuttings from previous selection in a population of half - sibs progenies. The morphoagronomic analyses of clones was carried out at 180 days after transplantation and were evaluated plant height, stem diameter, number of primary branches and number of secondary branches, number of bunches and number of fruits per plant. Evaluating clones performance, significant results were found for the number of secondary branches. About analysis of genetic diversity, the measures of dissimilarity genetic varied from 0.62 to 13.11, this way, the UFRBPR14 and UFRBPR15 clones were more divergent. The Tocher method was efficient to verify formation of four groups. The characteristics that most contributed to the divergence among clones were branches number, height and number of bunches, and, stem diameter had lower contribution. The jatropha clones differed only in the secondary branches number and multivariate analysis showed divergence among the jatropha clones with formation of four groups. Also, branches number, plant height and number of bunches were characteristic that contributed to genetic divergence.

  18. Laying hens selected for low mortality: Behaviour in tests of fearfulness, anxiety and cognition

    NARCIS (Netherlands)

    Nordquist, R.E.; Heerkens, J.L.T.; Rodenburg, T.B.; Boks, S.; Ellen, E.D.; Staaij, van der F.

    2011-01-01

    Feather pecking and cannibalism in chickens can lead to injury or to death of the victims, and is thus a serious welfare and economic issue in modern poultry farming. A sib selection scheme has been initiated to genetically select a low mortality line (LML), which shows decreased mortality due to

  19. Distributions of Mutational Effects and the Estimation of Directional Selection in Divergent Lineages of Arabidopsis thaliana.

    Science.gov (United States)

    Park, Briton; Rutter, Matthew T; Fenster, Charles B; Symonds, V Vaughan; Ungerer, Mark C; Townsend, Jeffrey P

    2017-08-01

    Mutations are crucial to evolution, providing the ultimate source of variation on which natural selection acts. Due to their key role, the distribution of mutational effects on quantitative traits is a key component to any inference regarding historical selection on phenotypic traits. In this paper, we expand on a previously developed test for selection that could be conducted assuming a Gaussian mutation effect distribution by developing approaches to also incorporate any of a family of heavy-tailed Laplace distributions of mutational effects. We apply the test to detect directional natural selection on five traits along the divergence of Columbia and Landsberg lineages of Arabidopsis thaliana , constituting the first test for natural selection in any organism using quantitative trait locus and mutation accumulation data to quantify the intensity of directional selection on a phenotypic trait. We demonstrate that the results of the test for selection can depend on the mutation effect distribution specified. Using the distributions exhibiting the best fit to mutation accumulation data, we infer that natural directional selection caused divergence in the rosette diameter and trichome density traits of the Columbia and Landsberg lineages. Copyright © 2017 by the Genetics Society of America.

  20. Population structure, genetic variation and linkage disequilibrium in perennial ryegrass populations divergently selected for freezing tolerance

    Directory of Open Access Journals (Sweden)

    Mallikarjuna Rao eKovi

    2015-11-01

    Full Text Available Low temperature is one of the abiotic stresses seriously affecting the growth of perennial ryegrass (Lolium perenne L. Understanding the genetic control of freezing tolerance would aid in the development of cultivars of perennial ryegrass with improved adaptation to frost. A total number of 80 individuals (24 of High frost [HF]; 29 of Low frost [LF] and 27 of Unselected [US] from the second generation of the two divergently selected populations and an unselected control population were genotyped using 278 genome-wide SNPs derived from Lolium perenne L. transcriptome sequence. Our studies showed that the HF and LF populations are very divergent after selection for freezing tolerance, whereas the HF and US populations are more similar. Linkage disequilibrium (LD decay varied across the seven chromosomes and the conspicuous pattern of LD between the HF and LF population confirmed their divergence in freezing tolerance. Furthermore, two Fst outlier methods; finite island model (fdist by LOSITAN and hierarchical structure model using ARLEQUIN detected six loci under directional selection. These outlier loci are most probably linked to genes involved in freezing tolerance, cold adaptation and abiotic stress and might be the potential marker resources for breeding perennial ryegrass cultivars with improved freezing tolerance.

  1. 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

  2. Chemical variation in a dominant tree species: population divergence, selection and genetic stability across environments.

    Directory of Open Access Journals (Sweden)

    Julianne M O'Reilly-Wapstra

    Full Text Available Understanding among and within population genetic variation of ecologically important plant traits provides insight into the potential evolutionary processes affecting those traits. The strength and consistency of selection driving variability in traits would be affected by plasticity in differences among genotypes across environments (G×E. We investigated population divergence, selection and environmental plasticity of foliar plant secondary metabolites (PSMs in a dominant tree species, Eucalyptus globulus. Using two common garden trials we examined variation in PSMs at multiple genetic scales; among 12 populations covering the full geographic range of the species and among up to 60 families within populations. Significant genetic variation in the expression of many PSMs resides both among and within populations of E. globulus with moderate (e.g., sideroxylonal A h(2op = 0.24 to high (e.g., macrocarpal G h(2op = 0.48 narrow sense heritabilities and high coefficients of additive genetic variation estimated for some compounds. A comparison of Qst and Fst estimates suggest that variability in some of these traits may be due to selection. Importantly, there was no genetic by environment interaction in the expression of any of the quantitative chemical traits despite often significant site effects. These results provide evidence that natural selection has contributed to population divergence in PSMs in E. globulus, and identifies the formylated phloroglucinol compounds (particularly sideroxylonal and a dominant oil, 1,8-cineole, as candidates for traits whose genetic architecture has been shaped by divergent selection. Additionally, as the genetic differences in these PSMs that influence community phenotypes is stable across environments, the role of plant genotype in structuring communities is strengthened and these genotypic differences may be relatively stable under global environmental changes.

  3. Intrinsic incompatibilities evolving as a by-product of divergent ecological selection: Considering them in empirical studies on divergence with gene flow.

    Science.gov (United States)

    Kulmuni, J; Westram, A M

    2017-06-01

    The possibility of intrinsic barriers to gene flow is often neglected in empirical research on local adaptation and speciation with gene flow, for example when interpreting patterns observed in genome scans. However, we draw attention to the fact that, even with gene flow, divergent ecological selection may generate intrinsic barriers involving both ecologically selected and other interacting loci. Mechanistically, the link between the two types of barriers may be generated by genes that have multiple functions (i.e., pleiotropy), and/or by gene interaction networks. Because most genes function in complex networks, and their evolution is not independent of other genes, changes evolving in response to ecological selection can generate intrinsic barriers as a by-product. A crucial question is to what extent such by-product barriers contribute to divergence and speciation-that is whether they stably reduce gene flow. We discuss under which conditions by-product barriers may increase isolation. However, we also highlight that, depending on the conditions (e.g., the amount of gene flow and the strength of selection acting on the intrinsic vs. the ecological barrier component), the intrinsic incompatibility may actually destabilize barriers to gene flow. In practice, intrinsic barriers generated as a by-product of divergent ecological selection may generate peaks in genome scans that cannot easily be interpreted. We argue that empirical studies on divergence with gene flow should consider the possibility of both ecological and intrinsic barriers. Future progress will likely come from work combining population genomic studies, experiments quantifying fitness and molecular studies on protein function and interactions. © 2017 The Authors. Molecular Ecology Published by John Wiley & Sons Ltd.

  4. Effects of selected feed additives on the performance of laying hens given a diet rich in maize dried distiller's grains with solubles (DDGS).

    Science.gov (United States)

    Świątkiewicz, S; Arczewska-Włosek, A; Krawczyk, J; Puchała, M; Józefiak, D

    2013-01-01

    1. A total of 192 ISA Brown hens were given diets containing a high concentration of maize dried distiller's grains with solubles (DDGS) and the effect of selected feed additives on laying performance and egg quality was determined. 2. Birds were allocated to 8 treatment groups with 12 replicates (cages) of two hens and were given, from week 26 to 55, iso-caloric and iso-nitrogenous experimental diets with or without a high concentration of DDGS (200 g/kg). The diet containing DDGS was not supplemented or supplemented with enzymes (xylanase and phytase), sodium butyrate, probiotic bacteria (Lactobacillus salivarius) and a mixture of herbal extracts (Taraxaci siccum, Urticae siccum and Salviae siccum), inulin or chitosan. 3. The inclusion of DDGS in the diet had no effect on number of eggs produced, total egg mass, mean egg weight, feed intake or feed conversion ratio. Egg and eggshell quality parameters were also unaffected by dietary DDGS. The yolk colour score (points in Roche scale) was significantly increased by DDGS inclusion. DDGS in the diet caused some changes in the yolk lipid profile that were rather unfavourable from a dietary perspective (an increase of cholesterol content, and PUFA n-6/PUFA n-3 ratio). 4. During the experimental period (26-55 weeks of age) supplementation of the diet containing a high concentration of DDGS with enzymes, inulin as well as chitosan, increased number of eggs produced and daily egg mass. In older hens (50 weeks of age) inulin positively affected eggshell quality parameters, i.e. shell percentage, thickness and density. Diet supplementation with herb extracts, inulin or chitosan, decreased the content of cholesterol in yolks. 5. The results of this study suggest that DDGS may be incorporated up to a concentration of 200 g/kg in the diet of laying hens without any negative effects on egg performance. Moreover, supplementation of xylanase and phytase, as well as inulin and chitosan, can positively affect the performance of

  5. Population structure and strong divergent selection shape phenotypic diversification in maize landraces.

    Science.gov (United States)

    Pressoir, G; Berthaud, J

    2004-02-01

    To conserve the long-term selection potential of maize, it is necessary to investigate past and present evolutionary processes that have shaped quantitative trait variation. Understanding the dynamics of quantitative trait evolution is crucial to future crop breeding. We characterized population differentiation of maize landraces from the State of Oaxaca, Mexico for quantitative traits and molecular markers. Qst values were much higher than Fst values obtained for molecular markers. While low values of Fst (0.011 within-village and 0.003 among-villages) suggest that considerable gene flow occurred among the studied populations, high levels of population differentiation for quantitative traits were observed (ie an among-village Qst value of 0.535 for kernel weight). Our results suggest that although quantitative traits appear to be under strong divergent selection, a considerable amount of gene flow occurs among populations. Furthermore, we characterized nonproportional changes in the G matrix structure both within and among villages that are consequences of farmer selection. As a consequence of these differences in the G matrix structure, the response to multivariate selection will be different from one population to another. Large changes in the G matrix structure could indicate that farmers select for genes of major and pleiotropic effect. Farmers' decision and selection strategies have a great impact on phenotypic diversification in maize landraces.

  6. Divergent Selection and Then What Not: The Conundrum of Missing Reproductive Isolation in Misty Lake and Stream Stickleback

    Directory of Open Access Journals (Sweden)

    Katja Räsänen

    2012-01-01

    Full Text Available In ecological speciation, reproductive isolation evolves as a consequence of adaptation to different selective environments. A frequent contributor to this process is the evolution of positive assortative mate choice between ecotypes. We tested this expectation for lake and inlet stream threespine stickleback (Gasterosteus aculeatus from the Misty system (Vancouver Island, Canada, which show strong genetically based adaptive divergence and little genetic exchange in nature. This, and work on other stickleback systems, led us to expect positive assortative mating. Yet, our standard “no-choice” laboratory experiment on common-garden fish revealed no evidence for this—despite divergence in traits typically mediating assortative mating in stickleback. These results remind us that divergent natural selection may not inevitably lead to the evolution of positive assortative mate choice. The apparent lack of strong and symmetric reproductive barriers in this system presents a conundrum: why are such barriers not evident despite strong adaptive divergence and low gene flow in nature?

  7. Minimising the Kullback–Leibler Divergence for Model Selection in Distributed Nonlinear Systems

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    Oliver M. Cliff

    2018-01-01

    Full Text Available The Kullback–Leibler (KL divergence is a fundamental measure of information geometry that is used in a variety of contexts in artificial intelligence. We show that, when system dynamics are given by distributed nonlinear systems, this measure can be decomposed as a function of two information-theoretic measures, transfer entropy and stochastic interaction. More specifically, these measures are applicable when selecting a candidate model for a distributed system, where individual subsystems are coupled via latent variables and observed through a filter. We represent this model as a directed acyclic graph (DAG that characterises the unidirectional coupling between subsystems. Standard approaches to structure learning are not applicable in this framework due to the hidden variables; however, we can exploit the properties of certain dynamical systems to formulate exact methods based on differential topology. We approach the problem by using reconstruction theorems to derive an analytical expression for the KL divergence of a candidate DAG from the observed dataset. Using this result, we present a scoring function based on transfer entropy to be used as a subroutine in a structure learning algorithm. We then demonstrate its use in recovering the structure of coupled Lorenz and Rössler systems.

  8. The effects of testosterone on immune function in quail selected for divergent plasma corticosterone response.

    Science.gov (United States)

    Roberts, Mark L; Buchanan, Katherine L; Evans, Matthew R; Marin, Raul H; Satterlee, Daniel G

    2009-10-01

    The immunocompetence handicap hypothesis (ICHH) suggests that the male sex hormone testosterone has a dual effect; it controls the development and expression of male sexually selected signals, and it suppresses the immune system. Therefore only high quality males are able to fully express secondary sexual traits because only they can tolerate the immunosuppressive qualities of testosterone. A modified version of the ICHH suggests that testosterone causes immunosuppression indirectly by increasing the stress hormone corticosterone (CORT). Lines of Japanese quail (Coturnix japonica) selected for divergent responses in levels of plasma CORT were used to test these hypotheses. Within each CORT response line (as well as in a control stock) we manipulated levels of testosterone in castrated quail by treatment with zero (sham), low or high testosterone implants, before testing the birds' humoral immunity and phytohaemagglutinin (PHA)-induced immune response, as well as body condition. The PHA-induced response was not significantly affected by CORT selected line, testosterone treatment or their interaction. There was, however, a significant effect of CORT line on humoral immunity in that the control birds exhibited the greatest antibody production, but there was no significant effect of testosterone manipulation on humoral immunity. The males in the sham implant treatment group had significantly greater mass than the males in the high testosterone group, suggesting a negative effect of high testosterone on general body condition. We discuss these results in the context of current hypotheses in the field of sexual selection.

  9. Creativity and sensory gating indexed by the P50: selective versus leaky sensory gating in divergent thinkers and creative achievers.

    Science.gov (United States)

    Zabelina, Darya L; O'Leary, Daniel; Pornpattananangkul, Narun; Nusslock, Robin; Beeman, Mark

    2015-03-01

    Creativity has previously been linked with atypical attention, but it is not clear what aspects of attention, or what types of creativity are associated. Here we investigated specific neural markers of a very early form of attention, namely sensory gating, indexed by the P50 ERP, and how it relates to two measures of creativity: divergent thinking and real-world creative achievement. Data from 84 participants revealed that divergent thinking (assessed with the Torrance Test of Creative Thinking) was associated with selective sensory gating, whereas real-world creative achievement was associated with "leaky" sensory gating, both in zero-order correlations and when controlling for academic test scores in a regression. Thus both creativity measures related to sensory gating, but in opposite directions. Additionally, divergent thinking and real-world creative achievement did not interact in predicting P50 sensory gating, suggesting that these two creativity measures orthogonally relate to P50 sensory gating. Finally, the ERP effect was specific to the P50 - neither divergent thinking nor creative achievement were related to later components, such as the N100 and P200. Overall results suggest that leaky sensory gating may help people integrate ideas that are outside of focus of attention, leading to creativity in the real world; whereas divergent thinking, measured by divergent thinking tests which emphasize numerous responses within a limited time, may require selective sensory processing more than previously thought. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. The Effect of Divergent Selection on 4-wk BW on the Shape of Growth Curve in Japanese Quail

    Directory of Open Access Journals (Sweden)

    H Beyki

    2011-12-01

    Full Text Available The current study was conducted to investigate the effect of short-term divergent selection on the shape growth curve in different lines of Japanese quail. The Quail lines utilized in this study were two divergently selected for high (HW and low (LW 4-wk body weight during 7 generation and also a control line (C. The Richard function parameters were used to describe growth curves of different lines. The weight at hatch was approximately similar among lines (8.08 g, 7.55 g and 8.76 g for HW, LW and C line respectively. The results of current study indicated that the selected lines (HW & LW were immediately diverged from the C line after hatch. Sexes within each line had no difference in average growth rate, age and body weight at inflection point and adult body weight. However significant differences were found in the growth curve parameters among lines. The results of current study indicated that short term divergent selection for 4-wk BW in Japanese quail can change the growth pattern and the carcass compartments of the selected birds. Therefore to avoid undesirable side effects due to selection in Japanese quails it is recommended to consider the growth pattern changes of the selected birds in the breeding programs

  11. Balancing selection on a regulatory region exhibiting ancient variation that predates human-neandertal divergence.

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    Omer Gokcumen

    2013-04-01

    Full Text Available Ancient population structure shaping contemporary genetic variation has been recently appreciated and has important implications regarding our understanding of the structure of modern human genomes. We identified a ∼36-kb DNA segment in the human genome that displays an ancient substructure. The variation at this locus exists primarily as two highly divergent haplogroups. One of these haplogroups (the NE1 haplogroup aligns with the Neandertal haplotype and contains a 4.6-kb deletion polymorphism in perfect linkage disequilibrium with 12 single nucleotide polymorphisms (SNPs across diverse populations. The other haplogroup, which does not contain the 4.6-kb deletion, aligns with the chimpanzee haplotype and is likely ancestral. Africans have higher overall pairwise differences with the Neandertal haplotype than Eurasians do for this NE1 locus (p<10⁻¹⁵. Moreover, the nucleotide diversity at this locus is higher in Eurasians than in Africans. These results mimic signatures of recent Neandertal admixture contributing to this locus. However, an in-depth assessment of the variation in this region across multiple populations reveals that African NE1 haplotypes, albeit rare, harbor more sequence variation than NE1 haplotypes found in Europeans, indicating an ancient African origin of this haplogroup and refuting recent Neandertal admixture. Population genetic analyses of the SNPs within each of these haplogroups, along with genome-wide comparisons revealed significant FST (p = 0.00003 and positive Tajima's D (p = 0.00285 statistics, pointing to non-neutral evolution of this locus. The NE1 locus harbors no protein-coding genes, but contains transcribed sequences as well as sequences with putative regulatory function based on bioinformatic predictions and in vitro experiments. We postulate that the variation observed at this locus predates Human-Neandertal divergence and is evolving under balancing selection, especially among European

  12. Holstein-Friesian calves selected for divergence in residual feed intake during growth exhibited significant but reduced residual feed intake divergence in their first lactation.

    Science.gov (United States)

    Macdonald, K A; Pryce, J E; Spelman, R J; Davis, S R; Wales, W J; Waghorn, G C; Williams, Y J; Marett, L C; Hayes, B J

    2014-03-01

    Residual feed intake (RFI), as a measure of feed conversion during growth, was estimated for around 2,000 growing Holstein-Friesian heifer calves aged 6 to 9 mo in New Zealand and Australia, and individuals from the most and least efficient deciles (low and high RFI phenotypes) were retained. These animals (78 New Zealand cows, 105 Australian cows) were reevaluated during their first lactation to determine if divergence for RFI observed during growth was maintained during lactation. Mean daily body weight (BW) gain during assessment as calves had been 0.86 and 1.15 kg for the respective countries, and the divergence in RFI between most and least efficient deciles for growth was 21% (1.39 and 1.42 kg of dry matter, for New Zealand and Australia, respectively). At the commencement of evaluation during lactation, the cows were aged 26 to 29 mo. All were fed alfalfa and grass cubes; it was the sole diet in New Zealand, whereas 6 kg of crushed wheat/d was also fed in Australia. Measurements of RFI during lactation occurred for 34 to 37 d with measurements of milk production (daily), milk composition (2 to 3 times per week), BW and BW change (1 to 3 times per week), as well as body condition score (BCS). Daily milk production averaged 13.8 kg for New Zealand cows and 20.0 kg in Australia. No statistically significant differences were observed between calf RFI decile groups for dry matter intake, milk production, BW change, or BCS; however a significant difference was noted between groups for lactating RFI. Residual feed intake was about 3% lower for lactating cows identified as most efficient as growing calves, and no negative effects on production were observed. These results support the hypothesis that calves divergent for RFI during growth are also divergent for RFI when lactating. The causes for this reduced divergence need to be investigated to ensure that genetic selection programs based on low RFI (better efficiency) are robust. Copyright © 2014 American Dairy

  13. A phenome database (NEAUHLFPD) designed and constructed for broiler lines divergently selected for abdominal fat content.

    Science.gov (United States)

    Li, Min; Dong, Xiang-yu; Liang, Hao; Leng, Li; Zhang, Hui; Wang, Shou-zhi; Li, Hui; Du, Zhi-Qiang

    2017-05-20

    Effective management and analysis of precisely recorded phenotypic traits are important components of the selection and breeding of superior livestocks. Over two decades, we divergently selected chicken lines for abdominal fat content at Northeast Agricultural University (Northeast Agricultural University High and Low Fat, NEAUHLF), and collected large volume of phenotypic data related to the investigation on molecular genetic basis of adipose tissue deposition in broilers. To effectively and systematically store, manage and analyze phenotypic data, we built the NEAUHLF Phenome Database (NEAUHLFPD). NEAUHLFPD included the following phenotypic records: pedigree (generations 1-19) and 29 phenotypes, such as body sizes and weights, carcass traits and their corresponding rates. The design and construction strategy of NEAUHLFPD were executed as follows: (1) Framework design. We used Apache as our web server, MySQL and Navicat as database management tools, and PHP as the HTML-embedded language to create dynamic interactive website. (2) Structural components. On the main interface, detailed introduction on the composition, function, and the index buttons of the basic structure of the database could be found. The functional modules of NEAUHLFPD had two main components: the first module referred to the physical storage space for phenotypic data, in which functional manipulation on data can be realized, such as data indexing, filtering, range-setting, searching, etc.; the second module related to the calculation of basic descriptive statistics, where data filtered from the database can be used for the computation of basic statistical parameters and the simultaneous conditional sorting. NEAUHLFPD could be used to effectively store and manage not only phenotypic, but also genotypic and genomics data, which can facilitate further investigation on the molecular genetic basis of chicken adipose tissue growth and development, and expedite the selection and breeding of broilers

  14. A genome-wide association study in a large F2-cross of laying hens reveals novel genomic regions associated with feather pecking and aggressive pecking behavior

    OpenAIRE

    Lutz, Vanessa; Stratz, Patrick; Preu?, Siegfried; Tetens, Jens; Grashorn, Michael A.; Bessei, Werner; Bennewitz, J?rn

    2017-01-01

    Background Feather pecking and aggressive pecking in laying hens are serious economic and welfare issues. In spite of extensive research on feather pecking during the last decades, the motivation for this behavior is still not clear. A small to moderate heritability has frequently been reported for these traits. Recently, we identified several single-nucleotide polymorphisms (SNPs) associated with feather pecking by mapping selection signatures in two divergent feather pecking lines. Here, we...

  15. Unemployment and health selection in diverging economic conditions: Compositional changes? Evidence from 28 European countries.

    Science.gov (United States)

    Heggebø, Kristian; Dahl, Espen

    2015-11-04

    Unemployment and health selection in diverging economic conditions: Compositional changes? Evidence from 28 european countries. People with ill health tend to be overrepresented among the unemployment population. The relationship between health and unemployment might, however, be sensitive to the overall economic condition. Specifically, the health composition of the unemployment population could change dramatically when the economy takes a turn for the worse. Using EU-SILC cross sectional data from 2007 (pre-crisis) and 2011 (during crisis) and linear regression models, this paper investigates the relationship between health and unemployment probabilities under differing economic conditions in 28 European countries. The countries are classified according to (i) the level of and (ii) increase in unemployment rate (i.e. >10 percent and doubling of unemployment rate = crisis country). Firstly, the unemployment likelihood for people with ill health is remarkably stable over time in Europe: the coefficients are very similar in pre-crisis and crisis years. Secondly, people with ill health have experienced unemployment to a lesser extent than those with good health status in the crisis year (when we pool the data and compare 2007 and 2011), but only in the countries with a high and rising unemployment rate. The health composition of the unemployment population changes significantly for the better, but only in those European countries that have been severely hit by the current economic crisis.

  16. Spatially variable natural selection and the divergence between parapatric subspecies of lodgepole pine (Pinus contorta, Pinaceae).

    Science.gov (United States)

    Eckert, Andrew J; Shahi, Hurshbir; Datwyler, Shannon L; Neale, David B

    2012-08-01

    Plant populations arrayed across sharp environmental gradients are ideal systems for identifying the genetic basis of ecologically relevant phenotypes. A series of five uplifted marine terraces along the northern coast of California represents one such system where morphologically distinct populations of lodgepole pine (Pinus contorta) are distributed across sharp soil gradients ranging from fertile soils near the coast to podzolic soils ca. 5 km inland. A total of 92 trees was sampled across four coastal marine terraces (N = 10-46 trees/terrace) located in Mendocino County, California and sequenced for a set of 24 candidate genes for growth and responses to various soil chemistry variables. Statistical analyses relying on patterns of nucleotide diversity were employed to identify genes whose diversity patterns were inconsistent with three null models. Most genes displayed patterns of nucleotide diversity that were consistent with null models (N = 19) or with the presence of paralogs (N = 3). Two genes, however, were exceptional: an aluminum responsive ABC-transporter with F(ST) = 0.664 and an inorganic phosphate transporter characterized by divergent haplotypes segregating at intermediate frequencies in most populations. Spatially variable natural selection along gradients of aluminum and phosphate ion concentrations likely accounted for both outliers. These results shed light on some of the genetic components comprising the extended phenotype of this ecosystem, as well as highlight ecotones as fruitful study systems for the detection of adaptive genetic variants.

  17. 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...

  18. Metabolic risk factors in mice divergently selected for BMR fed high fat and high carb diets.

    Science.gov (United States)

    Sadowska, Julita; Gębczyński, Andrzej K; Konarzewski, Marek

    2017-01-01

    Factors affecting contribution of spontaneous physical activity (SPA; activity associated with everyday tasks) to energy balance of humans are not well understood, as it is not clear whether low activity is related to dietary habits, precedes obesity or is a result of thereof. In particular, human studies on SPA and basal metabolic rates (BMR, accounting for >50% of human energy budget) and their associations with diet composition, metabolic thrift and obesity are equivocal. To clarify these ambiguities we used a unique animal model-mice selected for divergent BMR rates (the H-BMR and L-BMR line type) presenting a 50% between-line type difference in the primary selected trait. Males of each line type were divided into three groups and fed either a high fat, high carb or a control diet. They then spent 4 months in individual cages under conditions emulating human "sedentary lifestyle", with SPA followed every month and measurements of metabolic risk indicators (body fat mass %, blood lipid profile, fasting blood glucose levels and oxidative damage in the livers, kidneys and hearts) taken at the end of study. Mice with genetically determined high BMR assimilated more energy and had higher SPA irrespective of type of diet. H-BMR individuals were characterized by lower dry body fat mass %, better lipid profile and lower fasting blood glucose levels, but higher oxidative damage in the livers and hearts. Genetically determined high BMR may be a protective factor against diet-induced obesity and most of the metabolic syndrome indicators. Elevated spontaneous activity is correlated with high BMR, and constitutes an important factor affecting individual capability to sustain energy balance even under energy dense diets.

  19. Effect of dietary restriction on immune response of laboratory mice divergently selected for basal metabolic rate.

    Science.gov (United States)

    Książek, Aneta; Konarzewski, Marek

    2012-01-01

    To study whether dietary restriction (DR; 70% of ad lib. feeding)-elicited immunosuppression results from the trade-off between the costs of mounting an immune response and the metabolic costs of maintenance, we subjected mice from two divergent lines selected for high basal metabolic rate (H-BMR) and low BMR (L-BMR) to 4 wk of DR and then challenged them with keyhole limpet hemocyanin (KLH) antigen. Those line types differ genetically with respect to BMR and to the mass of metabolically expensive internal organs, which are larger in H-BMR mice. In mice of both line types, DR resulted in a significant reduction of body mass, an immune response, and the downsizing of spleen, lymph nodes, thymus, heart, and kidneys but not small intestines. DR resulted in a greater reduction of the spleen and lymph nodes in mice of the H-BMR line type, whereas the thymus was more affected in L-BMR line type. In contrast, immunization resulted in an increase of liver mass in DR mice of both line types. A comparison of the results of current and earlier studies on the same mouse line types suggests that metabolic trade-offs involving the costs of an immune response are more apparent when animals are forced to increase energy demands (e.g., by cold exposure) compared to when energy demands are decreased through DR. Our findings also suggest that divelrgent selection on BMR resulted in between-line-type differences in T-cell- and B-cell-mediated types of an immune response. More generally, our results indicate that production of a wide repertoire of antibodies is not correlated with high BMR.

  20. Short-term spatial memory responses in aged Japanese quail selected for divergent adrenocortical stress responsiveness.

    Science.gov (United States)

    Suhr, C L; Schmidt, J B; Treese, S T; Satterlee, D G

    2010-04-01

    Stress-induced glucocorticoids can dampen learning and spatial memory via neuronal damage to the hippocampus. Cognition losses can be transient (associated with acute stress episodes) or permanent as in aged individuals who show chronic glucocorticoid-induced accelerated brain aging and neurodegeneration (dementia). Thus, chronic versus acute stress effects on spatial memory responses of quail selected for reduced (low stress, LS) or exaggerated (high stress, HS) plasma corticosterone (B) response to brief restraint were assessed. Aged food-motivated male LS and HS quail were tested for 10 min in a feed-baited 8-arm radial arm maze (RAM) 1) at 255 d of age (quail who had experienced lifelong management stressors but who were otherwise never intentionally stressed; that is, chronically stressed birds), 2) on the next day post-acute stressor treatment (5 min of restraint), and 3) on the next day without treatment (acute stress recovery). The RAM tests used the win-shift procedure in which visited arms were not rebaited. Radial arm maze performance was measured by determination of the total number of arm choices made, the number of correct entries made into baited arms out of the first 8 choices, the time required to make a choice, and the number of pellets eaten. Line effects (P LS), and number of pellets eaten (HS RAM testing nor its interaction with line further influenced these variables. Thus, although selection for divergent plasma B responsiveness to an acute stressor was found to be associated with severe impairment of spatial memory in aged male HS compared with LS quail, the observed spatial memory impairments (HS > LS) could not be further altered by acute stressor treatment. Line differences in cognition may reflect lifelong management-induced stress episodes that periodically produce higher plasma B responses in HS than LS quail, which underlie HS quail memory deficits, or other etiologies, or both.

  1. Henning Bergenholtz

    African Journals Online (AJOL)

    Riette Ruthven

    tion of the grammatical variant, selection of collocations, etc.)? In many ways ..... infinitive as lemma, followed by the present, the preterite and the past tense: (1) vejlede verb 〈-r, vejledte (710 ... nary user. He is a teacher of Danish at a secondary school, and his name is Os- kar. ... Here a very simple division with an extreme ...

  2. Life cycle biological efficiency of mice divergently selected for heat loss.

    Science.gov (United States)

    Bhatnagar, A S; Nielsen, M K

    2014-08-01

    Divergent selection in mice for heat loss was conducted in 3 independent replicates creating a high maintenance, high heat loss (MH) and low maintenance, low heat loss (ML) line and unselected control (MC). Improvement in feed efficiency was observed in ML mice due to a reduced maintenance energy requirement but there was also a slight decline in reproductive performance, survivability, and lean content, particularly when compared to MC animals. The objective of this study was to model a life cycle scenario similar to a livestock production system and calculate total inputs and outputs to estimate overall biological efficiency of these lines and determine if reduced feed intake resulted in improved life cycle efficiency. Feed intake, reproductive performance, growth, and body composition were recorded on 21 mating pairs from each line × replicate combination, cohabitated at 7 wk of age and maintained for up to 1 yr unless culled. Proportion of animals at each parity was calculated from survival rates estimated from previous research when enforcing a maximum of 4, 8, or 12 allowed parities. This parity distribution was then combined with values from previous studies to calculate inputs and outputs of mating pairs and offspring produced in a single cycle at equilibrium. Offspring output was defined as kilograms of lean output of offspring at 49 d. Offspring input was defined as megacalories of energy intake for growing offspring from 21 to 49 d. Parent output was defined as kilograms of lean output of culled parents. Parent input was defined as megacalories of energy intake for mating pairs from weaning of one parity to weaning of the next. Offspring output was greatest in MC mice due to superior BW and numbers weaned, while output was lowest in ML mice due to smaller litter sizes and lean content. Parent output did not differ substantially between lines but was greatest in MH mice due to poorer survival rates resulting in more culled animals. Input was greatest in

  3. Finite Divergence

    DEFF Research Database (Denmark)

    Hansen, Michael Edberg; Pandya, P. K.; Chaochen, Zhou

    1995-01-01

    the framework of duration calculus. Axioms and proof rules are given. Patterns of occurrence of divergence are classified into dense divergence, accumulative divergence and discrete divergence by appropriate axioms. Induction rules are given for reasoning about discrete divergence...

  4. Selection and geographic isolation influence hummingbird speciation: genetic, acoustic and morphological divergence in the wedge-tailed sabrewing (Campylopterus curvipennis

    Directory of Open Access Journals (Sweden)

    Ornelas Juan

    2011-02-01

    Full Text Available Abstract Background Mesoamerica is one of the most threatened biodiversity hotspots in the world, yet we are far from understanding the geologic history and the processes driving population divergence and speciation for most endemic taxa. In species with highly differentiated populations selective and/or neutral factors can induce rapid changes to traits involved in mate choice, promoting reproductive isolation between allopatric populations that can eventually lead to speciation. We present the results of genetic differentiation, and explore drift and selection effects in promoting acoustic and morphological divergence among populations of Campylopterus curvipennis, a lekking hummingbird with an extraordinary vocal variability across Mesoamerica. Results Analyses of two mitochondrial genes and ten microsatellite loci genotyped for 160 individuals revealed the presence of three lineages with no contemporary gene flow: C. c. curvipennis, C. c. excellens, and C. c. pampa disjunctly distributed in the Sierra Madre Oriental, the Tuxtlas region and the Yucatan Peninsula, respectively. Sequence mtDNA and microsatellite data were congruent with two diversification events: an old vicariance event at the Isthmus of Tehuantepec (c. 1.4 Ma, and a more recent Pleistocene split, isolating populations in the Tuxtlas region. Hummingbirds of the excellens group were larger, and those of the pampa group had shorter bills, and lineages that have been isolated the longest shared fewer syllables and differed in spectral and temporal traits of a shared syllable. Coalescent simulations showed that fixation of song types has occurred faster than expected under neutrality but the null hypothesis that morphological divergence resulted from drift was not rejected. Conclusions Our phylogeographic analyses uncovered the presence of three Mesoamerican wedge-tailed sabrewing lineages, which diverged at different time scales. These results highlight the importance of the

  5. The large soybean (Glycine max) WRKY TF family expanded by segmental duplication events and subsequent divergent selection among subgroups.

    Science.gov (United States)

    Yin, Guangjun; Xu, Hongliang; Xiao, Shuyang; Qin, Yajuan; Li, Yaxuan; Yan, Yueming; Hu, Yingkao

    2013-10-03

    WRKY genes encode one of the most abundant groups of transcription factors in higher plants, and its members regulate important biological process such as growth, development, and responses to biotic and abiotic stresses. Although the soybean genome sequence has been published, functional studies on soybean genes still lag behind those of other species. We identified a total of 133 WRKY members in the soybean genome. According to structural features of their encoded proteins and to the phylogenetic tree, the soybean WRKY family could be classified into three groups (groups I, II, and III). A majority of WRKY genes (76.7%; 102 of 133) were segmentally duplicated and 13.5% (18 of 133) of the genes were tandemly duplicated. This pattern was not apparent in Arabidopsis or rice. The transcriptome atlas revealed notable differential expression in either transcript abundance or in expression patterns under normal growth conditions, which indicated wide functional divergence in this family. Furthermore, some critical amino acids were detected using DIVERGE v2.0 in specific comparisons, suggesting that these sites have contributed to functional divergence among groups or subgroups. In addition, site model and branch-site model analyses of positive Darwinian selection (PDS) showed that different selection regimes could have affected the evolution of these groups. Sites with high probabilities of having been under PDS were found in groups I, II c, II e, and III. Together, these results contribute to a detailed understanding of the molecular evolution of the WRKY gene family in soybean. In this work, all the WRKY genes, which were generated mainly through segmental duplication, were identified in the soybean genome. Moreover, differential expression and functional divergence of the duplicated WRKY genes were two major features of this family throughout their evolutionary history. Positive selection analysis revealed that the different groups have different evolutionary rates

  6. Identifying selected regions from heterozygosity and divergence using a light-coverage genomic dataset from two human populations.

    Directory of Open Access Journals (Sweden)

    Taras K Oleksyk

    2008-03-01

    Full Text Available When a selective sweep occurs in the chromosomal region around a target gene in two populations that have recently separated, it produces three dramatic genomic consequences: 1 decreased multi-locus heterozygosity in the region; 2 elevated or diminished genetic divergence (F(ST of multiple polymorphic variants adjacent to the selected locus between the divergent populations, due to the alternative fixation of alleles; and 3 a consequent regional increase in the variance of F(ST (S(2F(ST for the same clustered variants, due to the increased alternative fixation of alleles in the loci surrounding the selection target. In the first part of our study, to search for potential targets of directional selection, we developed and validated a resampling-based computational approach; we then scanned an array of 31 different-sized moving windows of SNP variants (5-65 SNPs across the human genome in a set of European and African American population samples with 183,997 SNP loci after correcting for the recombination rate variation. The analysis revealed 180 regions of recent selection with very strong evidence in either population or both. In the second part of our study, we compared the newly discovered putative regions to those sites previously postulated in the literature, using methods based on inspecting patterns of linkage disequilibrium, population divergence and other methodologies. The newly found regions were cross-validated with those found in nine other studies that have searched for selection signals. Our study was replicated especially well in those regions confirmed by three or more studies. These validated regions were independently verified, using a combination of different methods and different databases in other studies, and should include fewer false positives. The main strength of our analysis method compared to others is that it does not require dense genotyping and therefore can be used with data from population-based genome SNP scans

  7. Adaptive divergence in flowering time among natural populations of Arabidopsis thaliana: Estimates of selection and QTL mapping.

    Science.gov (United States)

    Ågren, Jon; Oakley, Christopher G; Lundemo, Sverre; Schemske, Douglas W

    2017-03-01

    To identify the ecological and genetic mechanisms of local adaptation requires estimating selection on traits, identifying their genetic basis, and evaluating whether divergence in adaptive traits is due to conditional neutrality or genetic trade-offs. To this end, we conducted field experiments for three years using recombinant inbred lines (RILs) derived from two ecotypes of Arabidopsis thaliana (Italy, Sweden), and at each parental site examined selection on flowering time and mapped quantitative trait loci (QTL). There was strong selection for early flowering in Italy, but weak selection in Sweden. Eleven distinct flowering time QTL were detected, and for each the Italian genotype caused earlier flowering. Twenty-seven candidate genes were identified, two of which (FLC and VIN3) appear under major flowering time QTL in Italy. Seven of eight QTL in Italy with narrow credible intervals colocalized with previously reported fitness QTL, in comparison to three of four in Sweden. The results demonstrate that the magnitude of selection on flowering time differs strikingly between our study populations, that the genetic basis of flowering time variation is multigenic with some QTL of large effect, and suggest that divergence in flowering time between ecotypes is due mainly to conditional neutrality. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  8. Genomic architecture of habitat-related divergence and signature of directional selection in the body shapes of Gnathopogon fishes.

    Science.gov (United States)

    Kakioka, Ryo; Kokita, Tomoyuki; Kumada, Hiroki; Watanabe, Katsutoshi; Okuda, Noboru

    2015-08-01

    Evolution of ecomorphologically relevant traits such as body shapes is important to colonize and persist in a novel environment. Habitat-related adaptive divergence of these traits is therefore common among animals. We studied the genomic architecture of habitat-related divergence in the body shape of Gnathopogon fishes, a novel example of lake-stream ecomorphological divergence, and tested for the action of directional selection on body shape differentiation. Compared to stream-dwelling Gnathopogon elongatus, the sister species Gnathopogon caerulescens, exclusively inhabiting a large ancient lake, had an elongated body, increased proportion of the caudal region and small head, which would be advantageous in the limnetic environment. Using an F2 interspecific cross between the two Gnathopogon species (195 individuals), quantitative trait locus (QTL) analysis with geometric morphometric quantification of body shape and restriction-site associated DNA sequencing-derived markers (1622 loci) identified 26 significant QTLs associated with the interspecific differences of body shape-related traits. These QTLs had small to moderate effects, supporting polygenic inheritance of the body shape-related traits. Each QTL was mostly located on different genomic regions, while colocalized QTLs were detected for some ecomorphologically relevant traits that are proxy of body and caudal peduncle depths, suggesting different degree of modularity among traits. The directions of the body shape QTLs were mostly consistent with the interspecific difference, and QTL sign test suggested a genetic signature of directional selection in the body shape divergence. Thus, we successfully elucidated the genomic architecture underlying the adaptive changes of the quantitative and complex morphological trait in a novel system. © 2015 John Wiley & Sons Ltd.

  9. Single nucleotide polymorphisms unravel hierarchical divergence and signatures of selection among Alaskan sockeye salmon (Oncorhynchus nerka populations

    Directory of Open Access Journals (Sweden)

    Habicht Christopher

    2011-02-01

    Full Text Available Abstract Background Disentangling the roles of geography and ecology driving population divergence and distinguishing adaptive from neutral evolution at the molecular level have been common goals among evolutionary and conservation biologists. Using single nucleotide polymorphism (SNP multilocus genotypes for 31 sockeye salmon (Oncorhynchus nerka populations from the Kvichak River, Alaska, we assessed the relative roles of geography (discrete boundaries or continuous distance and ecology (spawning habitat and timing driving genetic divergence in this species at varying spatial scales within the drainage. We also evaluated two outlier detection methods to characterize candidate SNPs responding to environmental selection, emphasizing which mechanism(s may maintain the genetic variation of outlier loci. Results For the entire drainage, Mantel tests suggested a greater role of geographic distance on population divergence than differences in spawn timing when each variable was correlated with pairwise genetic distances. Clustering and hierarchical analyses of molecular variance indicated that the largest genetic differentiation occurred between populations from distinct lakes or subdrainages. Within one population-rich lake, however, Mantel tests suggested a greater role of spawn timing than geographic distance on population divergence when each variable was correlated with pairwise genetic distances. Variable spawn timing among populations was linked to specific spawning habitats as revealed by principal coordinate analyses. We additionally identified two outlier SNPs located in the major histocompatibility complex (MHC class II that appeared robust to violations of demographic assumptions from an initial pool of eight candidates for selection. Conclusions First, our results suggest that geography and ecology have influenced genetic divergence between Alaskan sockeye salmon populations in a hierarchical manner depending on the spatial scale. Second

  10. THE EFFECTS OF SODIUM SELENITE AND SELENIZED YEAST SUPPLEMENTATION INTO DIET FOR LAYING HENS ON SELECTED QUALITATIVE PARAMETERS OF TABLE EGGS

    Directory of Open Access Journals (Sweden)

    HENRIETA ARPÁŠOVÁ

    2009-10-01

    Full Text Available In this experiment the effects of supplementation of the diet for laying hens with sodium selenite (SS or selenized yeast (SY on whole egg and egg shell quality of layers were studied. The chickens of Shaver Starcross 288 strain were randomly divided at the day of hatching into 4 groups (n=12; in each. The birds were fed from Day 1 of life to 9 months of age with diets differing in amounts and/or forms of selenium. Control group received basal diet (BD containing selenium naturally occurring in feeds (0.1 mg Se/kg of dry matter (DM. First and second experimental group of chickens were fed with a same BD enriched with equivalent dose of Se 0.4 mg/kg DM in form of sodium selenite or selenized yeast, respectively. The feed for third experimental group of birds consisted of BD supplemented with selenized yeast to the final amount of selenium 1.0 mg/kg DM. The egg weight was significantly higher in the groups with SY supplementation only. On the contrary the egg shell ratio was significantly lower in the groups with SY supplementation in both amounts. The width of egg was significantly increased in the groups with selenium supplementation in both forms. The value of egg shell strength was significantly decreased in group with SY in the highest amount 0.9 mg/kg DM The average egg shell thickness was the highest in the experimental group with Se-yeast in amount 0.9 mg/kg DM, however different was not significant compared with control group. The results showed that the most of selected parameters of egg quality appeared to be significantly influenced by selenium supplementation into laying hen’s basal diet.

  11. Changes in genetic architecture during relaxation in Drosophila melanogaster selected on divergent virgin life span

    NARCIS (Netherlands)

    Vermeulen, CJ; Bijlsma, R

    Artificial selection experiments often confer important information on the genetic correlations constraining the evolution of life history. After artificial selection has ceased however, selection pressures in the culture environment can change the correlation matrix again. Here, we reinvestigate

  12. Can interbreeding of wild and artificially propagated animals be prevented by using broodstock selected for a divergent life history?

    Science.gov (United States)

    Seamons, Todd R; Hauser, Lorenz; Naish, Kerry A; Quinn, Thomas P

    2012-01-01

    Two strategies have been proposed to avoid negative genetic effects of artificially propagated individuals on wild populations: (i) integration of wild and captive populations to minimize domestication selection and (ii) segregation of released individuals from the wild population to minimize interbreeding. We tested the efficacy of the strategy of segregation by divergent life history in a steelhead trout, Oncorhynchus mykiss, system, where hatchery fish were selected to spawn months earlier than the indigenous wild population. The proportion of wild ancestry smolts and adults declined by 10–20% over the three generations since the hatchery program began. Up to 80% of the naturally produced steelhead in any given year were hatchery/wild hybrids. Regression model selection analysis showed that the proportion of hatchery ancestry smolts was lower in years when stream discharge was high, suggesting a negative effect of flow on reproductive success of early-spawning hatchery fish. Furthermore, proportions of hybrid smolts and adults were higher in years when the number of naturally spawning hatchery-produced adults was higher. Divergent life history failed to prevent interbreeding when physical isolation was ineffective, an inadequacy that is likely to prevail in many other situations. PMID:23144657

  13. Variation in Linked Selection and Recombination Drive Genomic Divergence during Allopatric Speciation of European and American Aspens.

    Science.gov (United States)

    Wang, Jing; Street, Nathaniel R; Scofield, Douglas G; Ingvarsson, Pär K

    2016-07-01

    Despite the global economic and ecological importance of forest trees, the genomic basis of differential adaptation and speciation in tree species is still poorly understood. Populus tremula and Populus tremuloides are two of the most widespread tree species in the Northern Hemisphere. Using whole-genome re-sequencing data of 24 P. tremula and 22 P. tremuloides individuals, we find that the two species diverged ∼2.2-3.1 million years ago, coinciding with the severing of the Bering land bridge and the onset of dramatic climatic oscillations during the Pleistocene. Both species have experienced substantial population expansions following long-term declines after species divergence. We detect widespread and heterogeneous genomic differentiation between species, and in accordance with the expectation of allopatric speciation, coalescent simulations suggest that neutral evolutionary processes can account for most of the observed patterns of genetic differentiation. However, there is an excess of regions exhibiting extreme differentiation relative to those expected under demographic simulations, which is indicative of the action of natural selection. Overall genetic differentiation is negatively associated with recombination rate in both species, providing strong support for a role of linked selection in generating the heterogeneous genomic landscape of differentiation between species. Finally, we identify a number of candidate regions and genes that may have been subject to positive and/or balancing selection during the speciation process. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

  14. 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

  15. 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.

  16. Phenotypic differentiation is associated with divergent sexual selection among closely related barn swallow populations

    Czech Academy of Sciences Publication Activity Database

    Wilkins, M. R.; Karaardic, H.; Vortman, Y.; Parchman, T. L.; Albrecht, Tomáš; Petrželková, Adéla; Özkan, L.; Pap, P. L.; Hubbard, J. K.; Hund, A. K.; Safran, R. J.

    2016-01-01

    Roč. 29, č. 12 (2016), s. 2410-2421 ISSN 1010-061X R&D Projects: GA MŠk(CZ) LH14045 Institutional support: RVO:68081766 Keywords : birds * natural selection * population genetics * sexual selection & conflicts * speciation Subject RIV: EG - Zoology Impact factor: 2.792, year: 2016

  17. Divergent selection on 63-day body weight in the rabbit: response on growth, carcass and muscle traits

    Directory of Open Access Journals (Sweden)

    Combes Sylvie

    2005-01-01

    Full Text Available Abstract The effects of selection for growth rate on weights and qualitative carcass and muscle traits were assessed by comparing two lines selected for live body weight at 63 days of age and a cryopreserved control population raised contemporaneously with generation 5 selected rabbits. The animals were divergently selected for five generations for either a high (H line or a low (L line body weight, based on their BLUP breeding value. Heritability (h2 was 0.22 for 63-d body weight (N = 4754. Growth performance and quantitative carcass traits in the C group were intermediate between the H and L lines (N = 390. Perirenal fat proportion (h2 = 0.64 and dressing out percentage (h2 = 0.55 ranked in the order L Semitendinosus muscle, and the mean diameter of the constitutive myofibres were reduced in the L line only (N = 140. In the Longissimus muscle (N = 180, the ultimate pH (h2 = 0.16 and the maximum shear force reached in the Warner-Braztler test (h2 = 0.57 were slightly modified by selection.

  18. The roles of genetic drift and natural selection in quantitative trait divergence along an altitudinal gradient in Arabidopsis thaliana.

    Science.gov (United States)

    Luo, Y; Widmer, A; Karrenberg, S

    2015-02-01

    Understanding how natural selection and genetic drift shape biological variation is a central topic in biology, yet our understanding of the agents of natural selection and their target traits is limited. We investigated to what extent selection along an altitudinal gradient or genetic drift contributed to variation in ecologically relevant traits in Arabidopsis thaliana. We collected seeds from 8 to 14 individuals from each of 14 A. thaliana populations originating from sites between 800 and 2700 m above sea level in the Swiss Alps. Seed families were grown with and without vernalization, corresponding to winter-annual and summer-annual life histories, respectively. We analyzed putatively neutral genetic divergence between these populations using 24 simple sequence repeat markers. We measured seven traits related to growth, phenology and leaf morphology that are rarely reported in A. thaliana and performed analyses of altitudinal clines, as well as overall QST-FST comparisons and correlation analyses among pair-wise QST, FST and altitude of origin differences. Multivariate analyses suggested adaptive differentiation along altitude in the entire suite of traits, particularly when expressed in the summer-annual life history. Of the individual traits, a decrease in rosette leaf number in the vegetative state and an increase in leaf succulence with increasing altitude could be attributed to adaptive divergence. Interestingly, these patterns relate well to common within- and between-species trends of smaller plant size and thicker leaves at high altitude. Our results thus offer exciting possibilities to unravel the underlying mechanisms for these conspicuous trends using the model species A. thaliana.

  19. Multifarious selection through environmental change: acidity and predator-mediated adaptive divergence in the moor frog (Rana arvalis).

    Science.gov (United States)

    Egea-Serrano, Andrés; Hangartner, Sandra; Laurila, Anssi; Räsänen, Katja

    2014-04-07

    Environmental change can simultaneously cause abiotic stress and alter biological communities, yet adaptation of natural populations to co-changing environmental factors is poorly understood. We studied adaptation to acid and predator stress in six moor frog (Rana arvalis) populations along an acidification gradient, where abundance of invertebrate predators increases with increasing acidity of R. arvalis breeding ponds. First, we quantified divergence among the populations in anti-predator traits (behaviour and morphology) at different rearing conditions in the laboratory (factorial combinations of acid or neutral pH and the presence or the absence of a caged predator). Second, we evaluated relative fitness (survival) of the populations by exposing tadpoles from the different rearing conditions to predation by free-ranging dragonfly larvae. We found that morphological defences (relative tail depth) as well as survival of tadpoles under predation increased with increasing pond acidity (under most experimental conditions). Tail depth and larval size mediated survival differences among populations, but the contribution of trait divergence to survival was strongly dependent on prior rearing conditions. Our results indicate that R. arvalis populations are adapted to the elevated predator pressure in acidified ponds and emphasize the importance of multifarious selection via both direct (here: pH) and indirect (here: predators) environmental changes.

  20. Multifarious selection through environmental change: acidity and predator-mediated adaptive divergence in the moor frog (Rana arvalis)

    Science.gov (United States)

    Egea-Serrano, Andrés; Hangartner, Sandra; Laurila, Anssi; Räsänen, Katja

    2014-01-01

    Environmental change can simultaneously cause abiotic stress and alter biological communities, yet adaptation of natural populations to co-changing environmental factors is poorly understood. We studied adaptation to acid and predator stress in six moor frog (Rana arvalis) populations along an acidification gradient, where abundance of invertebrate predators increases with increasing acidity of R. arvalis breeding ponds. First, we quantified divergence among the populations in anti-predator traits (behaviour and morphology) at different rearing conditions in the laboratory (factorial combinations of acid or neutral pH and the presence or the absence of a caged predator). Second, we evaluated relative fitness (survival) of the populations by exposing tadpoles from the different rearing conditions to predation by free-ranging dragonfly larvae. We found that morphological defences (relative tail depth) as well as survival of tadpoles under predation increased with increasing pond acidity (under most experimental conditions). Tail depth and larval size mediated survival differences among populations, but the contribution of trait divergence to survival was strongly dependent on prior rearing conditions. Our results indicate that R. arvalis populations are adapted to the elevated predator pressure in acidified ponds and emphasize the importance of multifarious selection via both direct (here: pH) and indirect (here: predators) environmental changes. PMID:24552840

  1. Effects of Divergent Selection for Fear of Humans on Behaviour in Red Junglefowl.

    Directory of Open Access Journals (Sweden)

    Beatrix Agnvall

    Full Text Available Domestication has caused a range of similar phenotypic changes across taxa, relating to physiology, morphology and behaviour. It has been suggested that this recurring domesticated phenotype may be a result of correlated responses to a central trait, namely increased tameness. We selected Red Junglefowl, the ancestors of domesticated chickens, during five generations for reduced fear of humans. This caused a marked and significant response in tameness, and previous studies have found correlated effects on growth, metabolism, reproduction, and some behaviour not directly selected for. Here, we report the results from a series of behavioural tests carried out on the initial parental generation (P0 and the fifth selected generation (S5, focusing on behaviour not functionally related to tameness, in order to study any correlated effects. Birds were tested for fear of humans, social reinstatement tendency, open field behaviour at two different ages, foraging/exploration, response to a simulated aerial predator attack and tonic immobility. In S5, there were no effects of selection on foraging/exploration or tonic immobility, while in the social reinstatement and open field tests there were significant interactions between selection and sex. In the aerial predator test, there were significant main effects of selection, indicating that fear of humans may represent a general wariness towards predators. In conclusion, we found only small correlated effects on behaviours not related to the tameness trait selected for, in spite of them showing high genetic correlations to fear of humans in a previous study on the same population. This suggests that species-specific behaviour is generally resilient to changes during domestication.

  2. Effects of Divergent Selection for Fear of Humans on Behaviour in Red Junglefowl

    Science.gov (United States)

    Agnvall, Beatrix; Jensen, Per

    2016-01-01

    Domestication has caused a range of similar phenotypic changes across taxa, relating to physiology, morphology and behaviour. It has been suggested that this recurring domesticated phenotype may be a result of correlated responses to a central trait, namely increased tameness. We selected Red Junglefowl, the ancestors of domesticated chickens, during five generations for reduced fear of humans. This caused a marked and significant response in tameness, and previous studies have found correlated effects on growth, metabolism, reproduction, and some behaviour not directly selected for. Here, we report the results from a series of behavioural tests carried out on the initial parental generation (P0) and the fifth selected generation (S5), focusing on behaviour not functionally related to tameness, in order to study any correlated effects. Birds were tested for fear of humans, social reinstatement tendency, open field behaviour at two different ages, foraging/exploration, response to a simulated aerial predator attack and tonic immobility. In S5, there were no effects of selection on foraging/exploration or tonic immobility, while in the social reinstatement and open field tests there were significant interactions between selection and sex. In the aerial predator test, there were significant main effects of selection, indicating that fear of humans may represent a general wariness towards predators. In conclusion, we found only small correlated effects on behaviours not related to the tameness trait selected for, in spite of them showing high genetic correlations to fear of humans in a previous study on the same population. This suggests that species-specific behaviour is generally resilient to changes during domestication. PMID:27851792

  3. Testing for the Occurrence of Selective Episodes During the Divergence of Otophysan Fishes: Insights from Mitogenomics.

    Science.gov (United States)

    D'Anatro, Alejandro; Giorello, Facundo; Feijoo, Matías; Lessa, Enrique P

    2017-04-01

    How natural selection shapes biodiversity constitutes a topic of renewed interest during the last few decades. The division Otophysi comprises approximately two-thirds of freshwater fish diversity and probably underwent an extensive adaptive radiation derived from a single invasion of the supercontinent Pangaea, giving place to the evolution of the main five Otophysan lineages during a short period of time. Little is known about the factors involved in the processes that lead to lineage diversification among this group of fishes and identifying directional selection acting over protein-coding genes could offer clues about the processes acting on species diversification. The main objective of this study was to explore the otophysan mitochondrial genome evolution, in order to account for the possible signatures of selective events in this lineage, and to explore for the functional connotations of these molecular substitutions. Mainly, three different approaches were used: the "ω-based" BS-REL and MEME methods, implemented in the DATAMONKEY web server, and analysis of selection on amino acid properties, implemented in the software TreeSAAP. We found evidence of selective episodes along several branches of the evolutionary history of othophysan fishes. Analyses carried out using the BS-REL algorithm suggest episodic diversifying selection at basal branches of the otophysan lineage, which was also supported by analyses implemented in MEME and TreeSAAP. These results suggest that throughout the Siluriformes radiation, an important number of adaptive changes occurred in their mitochondrial genome. The metabolic consequences and ecological correlates of these molecular substitutions should be addressed in future studies.

  4. Selection in the thymus: pathway divergence and the commitment to life or death

    NARCIS (Netherlands)

    Canté-Barrett, K.

    2007-01-01

    Positive and negative selection are processes specific to thymocytes and are crucial to establish a diverse, yet self-tolerant T cell repertoire. Millions of thymocytes each contain a unique T cell receptor (TCR) due to random rearrangement of TCR gene segments, creating immense diversity. However,

  5. Genetic and non-genetic factors affecting rabbit doe sexual receptivity as estimated from one generation of divergent selection

    Directory of Open Access Journals (Sweden)

    M. Theau.Clément

    2015-09-01

    Full Text Available Sexual receptivity of rabbit does at insemination greatly influences fertility and is generally induced by hormones or techniques known as “biostimulation”. Searching for more sustainable farming systems, an original alternative would be to utilise the genetic pathway to increase the does’receptivity. The purpose of the present study was to identify genetic and non-genetic factors that influence rabbit doe sexual receptivity, in the context of a divergent selection experiment over 1 generation. The experiment spanned 2 generations: the founder generation (G0 consisting of 140 rabbit does, and the G1 generation comprising 2 divergently selected lines (L and H lines with 70 does each and 2 successive batches from each generation. The selection rate of the G0 females to form the G1 lines was 24/140. The selection tests consisted of 16 to 18 successive receptivity tests at the rate of 3 tests per week. On the basis of 4716 tests from 275 females, the average receptivity was 56.6±48.2%. A batch effect and a test operator effect were revealed. The contribution of females to the total variance was 20.0%, whereas that of bucks was only 1.1%. Throughout the experiment, 18.2% of does expressed a low receptivity (< 34%, 50.7% a medium one and 33.1% a high one (>66%. Some does were frequently receptive, whereas others were rarely receptive. The repeatability of sexual receptivity was approximately 20%. The results confirmed the high variability of sexual receptivity of non-lactating rabbit does maintained without any biostimulation or hormonal treatment. A lack of selection response on receptivity was observed. Accordingly, the heritability of receptivity was estimated at 0.01±0.02 from an animal model and at 0.02±0.03 from a  sire and dam model. The heritability of the average receptivity of a doe was calculated as 0.04. In agreement with the low estimated heritability, the heritability determined was no different from zero

  6. AFLP genome scanning reveals divergent selection in natural populations of Liriodendron chinense (Magnoliaceae along a latitudinal transect

    Directory of Open Access Journals (Sweden)

    Aihong eYang

    2016-05-01

    Full Text Available Understanding adaptive genetic variation and its relation to environmental factors are important for understanding how plants adapt to climate change and for managing genetic resources. Genome scans for the loci exhibiting either notably high or low levels of population differentiation (outlier loci provide one means of identifying genomic regions possibly associated with convergent or divergent selection. In this study, we combined AFLP genome scan and environmental association analysis to test for signals of natural selection in natural populations of Liriodendron chinense (Chinese Tulip Tree; Magnoliaceae along a latitudinal transect. We genotyped 276 individuals from 11 populations of L. chinense using 987 AFLP markers. Two complementary methods (Dfdist and BayeScan and association analysis between AFLP loci and climate factors were applied to detect outlier loci. Our analyses recovered both neutral and potentially adaptive genetic differentiation among populations of L. chinense. We found moderate genetic diversity within populations and high genetic differentiation among populations with reduced genetic diversity towards the periphery of the species ranges. Nine AFLP marker loci showed evidence of being outliers for population differentiation for both detection methods. Of these, six were strongly associated with at least one climate factor. Temperature, precipitation and radiation were found to be three important factors influencing local adaptation of L. chinense. The outlier AFLP loci are likely not the target of natural selection, but the neighboring genes of these loci might be involved in local adaptation. Hence, these candidates should be validated by further studies.

  7. Effects of wheat cultivar, metabolizable energy level, and xylanase supplementation to laying hens diet on performance, egg quality traits, and selected blood parameters

    Directory of Open Access Journals (Sweden)

    Masoud Mirzaee

    2014-10-01

    Full Text Available A 2 x 2 x 2 factorial arrangement of treatments was conducted to evaluate the effects of two dietary apparent metabolizable energy (AME levels (2,720 and 2,580 kcal kg-1 diet and enzyme (0 and 0.3 g kg-1 diet, Grindazym® GP 15,000 with mostly xylanase activity supplementation on the performance of laying hens fed diets based on two wheat cultivars (Marvdasht and Sardari. Experimental diets were formulated to have a constant energy to protein ratio and were fed to 65-wk-old Lohmann LSL-Lite laying hens for 7 wk. The lower level of AME reduced egg production and egg mass (p<0.05 and increased feed conversion ratio (p<0.05. Enzyme addition increased feed intake of the birds fed a diet with Sardari cultivar (p<0.05 but had no effect on feed intake of the birds fed a diet with Marvdasht cultivar (p>0.05. Nevertheless, birds receiving diets based on Marvdasht cultivar had higher feed intake and egg mass than that of those receiving diets based on Sardari cultivar (p<0.05. The birds fed diets based on Marvdasht cultivar produced less undesired eggs and had better yolk color as compared with the birds fed diets based on Sardari cultivar (p<0.05. The serum concentration of glucose increased by enzyme supplementation when birds receiving lower AME level (p<0.05. These results indicate that enzyme supplementation may have a positive effect on the feed intake of laying hens when fed on wheat-based diets; however, this effect is cultivar dependent and does not necessarily mean that enzyme supplementation always benefit production.

  8. Divergent Streams: Race-Gender Achievement Gaps at Selective Colleges and Universities

    OpenAIRE

    Massey, Douglas S.; Probasco, LiErin

    2010-01-01

    In this paper, we extend previous research on racial performance gaps at 28 selective US colleges and universities by examining differences in grade achievement and graduate rates across race-gender categories. Using data from the National Longitudinal Survey of Freshmen, we show that black males, black females, and Hispanic males attain significantly lower grades than other race-gender groups, and that black males are 35% less likely to graduate on-time than other race-gender groups. Analyse...

  9. Coevolution of parental investment and sexually selected traits drives sex-role divergence.

    Science.gov (United States)

    Fromhage, Lutz; Jennions, Michael D

    2016-08-18

    Sex-role evolution theory attempts to explain the origin and direction of male-female differences. A fundamental question is why anisogamy, the difference in gamete size that defines the sexes, has repeatedly led to large differences in subsequent parental care. Here we construct models to confirm predictions that individuals benefit less from caring when they face stronger sexual selection and/or lower certainty of parentage. However, we overturn the widely cited claim that a negative feedback between the operational sex ratio and the opportunity cost of care selects for egalitarian sex roles. We further argue that our model does not predict any effect of the adult sex ratio (ASR) that is independent of the source of ASR variation. Finally, to increase realism and unify earlier models, we allow for coevolution between parental investment and investment in sexually selected traits. Our model confirms that small initial differences in parental investment tend to increase due to positive evolutionary feedback, formally supporting long-standing, but unsubstantiated, verbal arguments.

  10. Divergent Streams: Race-Gender Achievement Gaps at Selective Colleges and Universities.

    Science.gov (United States)

    Massey, Douglas S; Probasco, Lierin

    2010-03-01

    In this paper, we extend previous research on racial performance gaps at 28 selective US colleges and universities by examining differences in grade achievement and graduate rates across race-gender categories. Using data from the National Longitudinal Survey of Freshmen, we show that black males, black females, and Hispanic males attain significantly lower grades than other race-gender groups, and that black males are 35% less likely to graduate on-time than other race-gender groups. Analyses consider an array of personal and institutional indicators of academic performance. Grades and graduation rates are improved by academic preparation (particularly high school GPA), scholarly effort, and, for graduation rates, membership in career-oriented or majority-white campus groups. Grade performance and graduation rates are undermined by a hostile racial climate on campus, family stress, and stereotype threat, all of which disproportionately affect minority students. We conclude with recommendations to college administrators for ways of selecting and supporting minority students to reduce differentials in academic achievement across race-gender groups.

  11. Cytokines Expression and Nitric Oxide Production under Induced Infection to Typhimurium in Chicken Lines Divergently Selected for Cutaneous Hypersensitivity

    Directory of Open Access Journals (Sweden)

    Rani Singh

    2012-07-01

    Full Text Available In the present study, the impact of Salmonella Typhimurium on cell-mediated immunity (CMI was investigated in 5 week-old immuno divergent broiler lines selected for the high and low response to phytohemagglutinin-P. The immune response was assessed in peripheral-blood mononuclear cells (PBMCs induced with Salmonella Typhimurium at different time intervals (0 h, 0.5 h, 2 h, 4 h, 6 h, 12 h and 24 h. The differential mRNA expression patterns of IFN-γ, IL-2 and iNOS were evaluated by quantitative real time PCR. In-vitro production of nitric oxide (NO was also estimated in the culture supernatant and correlated with iNOS mRNA expression. Present study showed higher production of NO in the high cell-mediated line (HCMI as compared to the low cell-mediated line (LCMI upon stimulation with Salmonella Typhimurium. Correspondingly, higher mRNA expression of iNOS and IFN-γ were observed in high response birds (HCMI; but IL-2 was down regulated in this line compared to the low response birds (LCMI. Significantly (p<0.05 higher expression of iNOS, IFN-γ and higher production of NO in high line indicated that the selection for PHA-P response might be employed for increasing the immune competence against Salmonella Typhimurium in chicken flocks.

  12. 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.

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

    Science.gov (United States)

    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.

  14. AFLP genome scans suggest divergent selection on colour patterning in allopatric colour morphs of a cichlid fish.

    Science.gov (United States)

    Mattersdorfer, Karin; Koblmüller, Stephan; Sefc, Kristina M

    2012-07-01

    Genome scan-based tests for selection are directly applicable to natural populations to study the genetic and evolutionary mechanisms behind phenotypic differentiation. We conducted AFLP genome scans in three distinct geographic colour morphs of the cichlid fish Tropheus moorii to assess whether the extant, allopatric colour pattern differentiation can be explained by drift and to identify markers mapping to genomic regions possibly involved in colour patterning. The tested morphs occupy adjacent shore sections in southern Lake Tanganyika and are separated from each other by major habitat barriers. The genome scans revealed significant genetic structure between morphs, but a very low proportion of loci fixed for alternative AFLP alleles in different morphs. This high level of polymorphism within morphs suggested that colour pattern differentiation did not result exclusively from neutral processes. Outlier detection methods identified six loci with excess differentiation in the comparison between a bluish and a yellow-blotch morph and five different outlier loci in comparisons of each of these morphs with a red morph. As population expansions and the genetic structure of Tropheus make the outlier approach prone to false-positive signals of selection, we examined the correlation between outlier locus alleles and colour phenotypes in a genetic and phenotypic cline between two morphs. Distributions of allele frequencies at one outlier locus were indeed consistent with linkage to a colour locus. Despite the challenges posed by population structure and demography, our results encourage the cautious application of genome scans to studies of divergent selection in subdivided and recently expanded populations. © 2012 Blackwell Publishing Ltd.

  15. Regulation of metabolism by dietary carbohydrates in two lines of rainbow trout divergently selected for muscle fat content.

    Science.gov (United States)

    Kamalam, Biju Sam; Medale, Françoise; Kaushik, Sadasivam; Polakof, Sergio; Skiba-Cassy, Sandrine; Panserat, Stephane

    2012-08-01

    Previous studies in two rainbow trout lines divergently selected for lean (L) or fat (F) muscle suggested that they differ in their ability to metabolise glucose. In this context, we investigated whether genetic selection for high muscle fat content led to a better capacity to metabolise dietary carbohydrates. Juvenile trout from the two lines were fed diets with or without gelatinised starch (17.1%) for 10 weeks, after which blood, liver, muscle and adipose tissues were sampled. Growth rate, feed efficiency and protein utilisation were lower in the F line than in the L line. In both lines, intake of carbohydrates was associated with a moderate post-prandial hyperglycaemia, a protein sparing effect, an enhancement of nutrient (TOR-S6) signalling cascade and a decrease of energy-sensing enzyme (AMPK). Gene expression of hepatic glycolytic enzymes was higher in the F line fed carbohydrates compared with the L line, but concurrently transcripts for the gluconeogenic enzymes was also higher in the F line, possibly impairing glucose homeostasis. However, the F line showed a higher gene expression of hepatic enzymes involved in lipogenesis and fatty acid bioconversion, in particular with an increased dietary carbohydrate intake. Enhanced lipogenic potential coupled with higher liver glycogen content in the F line suggests better glucose storage ability than the L line. Overall, the present study demonstrates the changes in hepatic intermediary metabolism resulting from genetic selection for high muscle fat content and dietary carbohydrate intake without, however, any interaction for an improved growth or glucose utilisation in the peripheral tissues.

  16. 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

  17. Divergent evolution and purifying selection of the H (FUT1 gene in New World monkeys (Primates, Platyrrhini

    Directory of Open Access Journals (Sweden)

    Bárbara do Nascimento Borges

    2004-01-01

    Full Text Available In the present study, the coding region of the H gene was sequenced and analyzed in fourteen genera of New World primates (Alouatta, Aotus, Ateles, Brachyteles, Cacajao, Callicebus, Callithrix, Cebus, Chiropotes, Lagothrix, Leontopithecus, Pithecia, Saguinus, and Saimiri, in order to investigate the evolution of the gene. The analyses revealed that this coding region contains 1,101 nucleotides, with the exception of Brachyteles, the callitrichines (Callithrix, Leontopithecus, and Saguinus and one species of Callicebus (moloch, in which one codon was deleted. In the primates studied, the high GC content (63%, the nonrandom distribution of codons and the low evolution rate of the gene (0.513 substitutions/site/MA in the order Primates suggest the action of a purifying type of selective pressure, confirmed by the Z-test. Our analyses did not identify mutations equivalent to those responsible for the H-deficient phenotypes found in humans, nor any other alteration that might explain the lack of expression of the gene in the erythrocytes of Neotropical monkeys. The phylogenetic trees obtained for the H gene and the distance matrix data suggest the occurrence of divergent evolution in the primates.

  18. Transcriptomic analysis of genes in the nitrogen recycling pathway of meat-type chickens divergently selected for feed efficiency.

    Science.gov (United States)

    Aggrey, S E; Lee, J; Karnuah, A B; Rekaya, R

    2014-04-01

    The understanding of the dynamics of ammonia detoxification and excretion in uricotelic species is lagging behind ureotelic species. The relative expression of genes involved in nitrogen recycling and feed efficiency in chickens is unknown. The objective of this study was to investigate the transcriptomics differences in key genes in the nitrogen (N) metabolism and purine biosynthesis pathway in a chicken population divergently selected for low (LRFI) or high (HRFI) residual feed intake at days 35 and 42 using duodenum, liver, pectoralis major (P. major) and kidney. There was a significant positive correlation between RFI and fecal N. The purine salvage pathway was activated in the LRFI compared with HRFI at days 42. The birds in the LRFI population attained greater feed efficiency by having lower FI, increasing their protein retention and producing adequate glutamine to maintain growth compared with the HRFI line. To maintain growth, excess N is deaminated mostly to generate purine nucleotides. Generating purine nucleotides primarily from the purine biosynthesis pathway is energetically costly, and to preserve energy, they preferentially generate nucleotides from the purine salvage pathway. The LRFI birds need to generate sufficient nucleotides to maintain growth despite reduced FI that then results in reduced fecal N. © 2013 Stichting International Foundation for Animal Genetics.

  19. Heat dissipation does not suppress an immune response in laboratory mice divergently selected for basal metabolic rate (BMR).

    Science.gov (United States)

    Książek, Aneta; Konarzewski, Marek

    2016-05-15

    The capacity for heat dissipation is considered to be one of the most important constraints on rates of energy expenditure in mammals. To date, the significance of this constraint has been tested exclusively under peak metabolic demands, such as during lactation. Here, we used a different set of metabolic stressors, which do not induce maximum energy expenditures and yet are likely to expose the potential constraining effect of heat dissipation. We compared the physiological responses of mice divergently selected for high (H-BMR) and low basal metabolic rate (L-BMR) to simultaneous exposure to the keyhole limpet haemocyanin (KLH) antigen and high ambient temperature (Ta). At 34°C (and at 23°C, used as a control), KLH challenge resulted in a transient increase in core body temperature (Tb) in mice of both line types (by approximately 0.4°C). Warm exposure did not produce line-type-dependent differences in Tb (which was consistently higher by ca. 0.6°C in H-BMR mice across both Ta values), nor did it result in the suppression of antibody synthesis. These findings were also supported by the lack of between-line-type differences in the mass of the thymus, spleen or lymph nodes. Warm exposure induced the downsizing of heat-generating internal organs (small intestine, liver and kidneys) and an increase in intrascapular brown adipose tissue mass. However, these changes were similar in scope in both line types. Mounting a humoral immune response in selected mice was therefore not affected by ambient temperature. Thus, a combined metabolic challenge of high Ta and an immune response did not appreciably compromise the capacity to dissipate heat, even in the H-BMR mice. © 2016. Published by The Company of Biologists Ltd.

  20. Effect of calorie restriction on spontaneous physical activity and body mass in mice divergently selected for basal metabolic rate (BMR).

    Science.gov (United States)

    Brzęk, Paweł; Gębczyński, Andrzej K; Książek, Aneta; Konarzewski, Marek

    2016-07-01

    Spontaneous physical activity (SPA) represents an important component of daily energy expenditures in animals and humans. Intra-specific variation in SPA may be related to the susceptibility to metabolic disease or obesity. In particular, reduced SPA under conditions of limited food availability may conserve energy and prevent loss of body and fat mass ('thrifty genotype hypothesis'). However, both SPA and its changes during food restriction show wide inter-individual variations. We studied the effect of 30% caloric restriction (CR) on SPA in laboratory mice divergently selected for high (H-BMR) and low (L-BMR) basal metabolic rate. Selection increased SPA in the H-BMR line but did not change it in the L-BMR mice. This effect reflected changes in SPA intensity but not SPA duration. CR increased SPA intensity more strongly in the L-BMR line than in the H-BMR line and significantly modified the temporal variation of SPA. However, the initial between-line differences in SPA were not affected by CR. Loss of body mass during CR did not differ between both lines. Our results show that the H-BMR mice can maintain their genetically determined high SPA under conditions of reduced food intake without sacrificing their body mass. We hypothesize that this pattern may reflect the higher flexibility in the energy budget in the H-BMR line, as we showed previously that mice from this line reduced their BMR during CR. These energy savings may allow for the maintenance of elevated SPA in spite of reduced food intake. We conclude that the effect of CR on SPA is in large part determined by the initial level of BMR, whose variation may account for the lack of universal pattern of behavioural responses to CR. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. A short-term divergent selection for resistance to Teladorsagia circumcincta in Romanov sheep using natural or artificial challenge

    Directory of Open Access Journals (Sweden)

    Cortet Jacques

    2004-03-01

    Full Text Available Abstract This experiment was conducted to assess the efficiency of selection on the basis of response to artificial challenges in order to breed sheep resistant to natural infection. A short-term divergent selection process was designed to estimate the genetic parameters of these two traits. Two flocks, including 100 Romanov ram lambs each, were challenged in 1990 when they were 6 months old. One flock received three artificial infections with 20 000 third-stage Teladorsagia circumcincta larvae, at intervals of 7 weeks. Faecal egg counts (FEC were performed on Days 22, 25 and 28 post infection (p.i. and the animals were drenched on Day 28 p.i. The other flock was grazed for 5 months on a pasture contaminated with the same species. Faecal samples were taken from the lambs at similar ages. About 5 rams with the lowest FEC and 5 with the highest FEC were selected in each flock and mated with unselected ewes. Their offspring (200 animals were challenged in 1992, half in the same way as their sires, and the other half by the other method. Because of a drought in the summer of 1990, it was necessary to repeat part of the experiment, and in 1992 the 5 and 8 rams with the lowest and highest FEC, respectively, were selected from the offspring challenged on the pasture in 1992 and were mated with unselected ewes. Their progeny (about 80 animals were challenged in 1994, half by natural infection, half by artificial infection. The mean FEC of the flock increased from the first to the third artificial infection. The natural infection was highly variable in different years, reflecting the difficulty of assessing resistance using this mode of challenge. Genetic parameters were estimated using animal models and REML solutions. The repeatabilities of the FEC following artificial and natural infection were 0.49 and 0.70 respectively within a period of one week, and 0.22 and 0.41 respectively for periods separated by intervals of 7 weeks; the heritabilities of the

  2. Short communication: grazing pattern of dairy cows that were selected for divergent residual feed intake as calves.

    Science.gov (United States)

    Gregorini, P; Waghorn, G C; Kuhn-Sherlock, B; Romera, A J; Macdonald, K A

    2015-09-01

    The aim of this study was to investigate and assess differences in the grazing pattern of 2 groups of mature dairy cows selected as calves for divergent residual feed intake (RFI). Sixteen Holstein-Friesian cows (471±31kg of body weight, 100 d in milk), comprising 8 cows selected as calves (6-8 mo old) for low (most efficient: CSCLowRFI) and 8 cows selected as calves for high (least efficient: CSCHighRFI) RFI, were used for the purpose of this study. Cows (n=16) were managed as a single group, and strip-grazed (24-h pasture allocation at 0800h) a perennial ryegrass sward for 31 d, with measurements taken during the last 21 d. All cows were equipped with motion sensors for the duration of the study, and jaw movements were measured for three 24-h periods during 3 random nonconsecutive days. Measurements included number of steps and jaw movements during grazing and rumination, plus fecal particle size distribution. Jaw movements were analyzed to identify bites, mastication (oral processing of ingesta) during grazing bouts, chewing during rumination, and to calculate grazing and rumination times for 24-h periods. Grazing and walking behavior were also analyzed in relation to the first meal of the day after the new pasture was allocated. Measured variables were subjected to multivariate analysis. Cows selected for low RFI as calves appeared to (a) prioritize grazing and rumination over idling; (b) take fewer steps, but with a higher proportion of grazing steps at the expense of nongrazing steps; and (c) increase the duration of the first meal and commenced their second meal earlier than CSCHighRFI. The CSCLowRFI had fewer jaw movements during eating (39,820 vs. 45,118 for CSCLowRFI and CSCHighRFI, respectively), more intense rumination (i.e., 5 more chews per bolus), and their feces had 30% less large particles than CSCHighRFI. These results suggest that CSCLowRFI concentrate their grazing activity to the time when fresh pasture is allocated, and graze more efficiently

  3. Altitudinal divergence in maternal thermoregulatory behaviour may be driven by differences in selection on offspring survival in a viviparous lizard

    NARCIS (Netherlands)

    Uller, Tobias; While, Geoffrey M.; Cadby, Chloe D.; Harts, Anna; O'Connor, Katherine; Pen, Ido; Wapstra, Erik

    Plastic responses to temperature during embryonic development are common in ectotherms, but their evolutionary relevance is poorly understood. Using a combination of field and laboratory approaches, we demonstrate altitudinal divergence in the strength of effects of maternal thermal opportunity on

  4. Mice divergently selected for high and low basal metabolic rates evolved different cell size and organ mass.

    Science.gov (United States)

    Maciak, S; Bonda-Ostaszewska, E; Czarnołęski, M; Konarzewski, M; Kozłowski, J

    2014-03-01

    Evolution of metabolic rates of multicellular organisms is hypothesized to reflect the evolution of their cell architecture. This is likely to stem from a tight link between the sizes of cells and nuclei, which are expected to be inversely related to cell metabolism. Here, we analysed basal metabolic rate (BMR), internal organ masses and the cell/nucleus size in different tissues of laboratory mice divergently selected for high/low mass-corrected BMR and four random-bred mouse lines. Random-bred lines had intermediate levels of BMR as compared to low- and high-BMR lines. Yet, this pattern was only partly consistent with the between-line differences in cell/nucleus sizes. Erythrocytes and skin epithelium cells were smaller in the high-BMR line than in other lines, but the cells of low-BMR and random-bred mice were similar in size. On the other hand, the size of hepatocytes, kidney proximal tubule cells and duodenum enterocytes were larger in high-BMR mice than other lines. All cell and nucleus sizes were positively correlated, which supports the role of the nucleus in cell size regulation. Our results suggest that the evolution of high BMR involves a reduction in cell size in specialized tissues, whose functions are primarily dictated by surface-to-volume ratios, such as erythrocytes. High BMR may, however, also incur an increase in cell size in tissues with an intense transcription and translation, such as hepatocytes. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  5. Genetic Divergence and Signatures of Natural Selection in Marginal Populations of a Keystone, Long-Lived Conifer, Eastern White Pine (Pinus strobus) from Northern Ontario

    Science.gov (United States)

    Chhatre, Vikram E.; Rajora, Om P.

    2014-01-01

    Marginal populations are expected to provide the frontiers for adaptation, evolution and range shifts of plant species under the anticipated climate change conditions. Marginal populations are predicted to show genetic divergence from central populations due to their isolation, and divergent natural selection and genetic drift operating therein. Marginal populations are also expected to have lower genetic diversity and effective population size (N e) and higher genetic differentiation than central populations. We tested these hypotheses using eastern white pine (Pinus strobus) as a model for keystone, long-lived widely-distributed plants. All 614 eastern white pine trees, in a complete census of two populations each of marginal old-growth, central old-growth, and central second-growth, were genotyped at 11 microsatellite loci. The central populations had significantly higher allelic and genotypic diversity, latent genetic potential (LGP) and N e than the marginal populations. However, heterozygosity and fixation index were similar between them. The marginal populations were genetically diverged from the central populations. Model testing suggested predominant north to south gene flow in the study area with curtailed gene flow to northern marginal populations. Signatures of natural selection were detected at three loci in the marginal populations; two showing divergent selection with directional change in allele frequencies, and one balancing selection. Contrary to the general belief, no significant differences were observed in genetic diversity, differentiation, LGP, and N e between old-growth and second-growth populations. Our study provides information on the dynamics of migration, genetic drift and selection in central versus marginal populations of a keystone long-lived plant species and has broad evolutionary, conservation and adaptation significance. PMID:24859159

  6. Genetic divergence and signatures of natural selection in marginal populations of a keystone, long-lived conifer, Eastern White Pine (Pinus strobus) from Northern Ontario.

    Science.gov (United States)

    Chhatre, Vikram E; Rajora, Om P

    2014-01-01

    Marginal populations are expected to provide the frontiers for adaptation, evolution and range shifts of plant species under the anticipated climate change conditions. Marginal populations are predicted to show genetic divergence from central populations due to their isolation, and divergent natural selection and genetic drift operating therein. Marginal populations are also expected to have lower genetic diversity and effective population size (Ne) and higher genetic differentiation than central populations. We tested these hypotheses using eastern white pine (Pinus strobus) as a model for keystone, long-lived widely-distributed plants. All 614 eastern white pine trees, in a complete census of two populations each of marginal old-growth, central old-growth, and central second-growth, were genotyped at 11 microsatellite loci. The central populations had significantly higher allelic and genotypic diversity, latent genetic potential (LGP) and Ne than the marginal populations. However, heterozygosity and fixation index were similar between them. The marginal populations were genetically diverged from the central populations. Model testing suggested predominant north to south gene flow in the study area with curtailed gene flow to northern marginal populations. Signatures of natural selection were detected at three loci in the marginal populations; two showing divergent selection with directional change in allele frequencies, and one balancing selection. Contrary to the general belief, no significant differences were observed in genetic diversity, differentiation, LGP, and Ne between old-growth and second-growth populations. Our study provides information on the dynamics of migration, genetic drift and selection in central versus marginal populations of a keystone long-lived plant species and has broad evolutionary, conservation and adaptation significance.

  7. Contrasted zinc hyperaccumulation levels between metallicolous and non-metallicolous populations of Arabidopsis halleri is driven by divergent selection

    Science.gov (United States)

    Babst-Kostecka, Alicja; Waldmann, Patrik; Pauwels, Maxime; Schat, Henk; Bourceaux, Angélique; Saumitou-Laprade, Pierre; Grodzińska, Krystyna; Frérot, Hélène

    2017-04-01

    hyperaccumulation (3000 mg kg-1) under these experimental conditions. The heritability estimates of zinc concentration in shoots for each population ranged from 0.277 to 0.903, and were considerably higher in metallicolous than non-metallicolous populations. The results of Qst-Fst comparisons suggested that differences in zinc hyperaccumulation levels between metallicolous and non-metallicolous populations may be driven by divergent selection, supporting the occurrence of local adaptation. These findings encourage further genetic and genomic research to uncover the genetic basis of local adaptation of A. halleri to contaminated environments. In particular, due to their enhanced zinc hyperaccumulation capacities non-metallicolous populations may be particularly promising for phytoremediation efforts.

  8. Henning Bergenholtz: Bibliovita

    DEFF Research Database (Denmark)

    Nielsen, Sandro; Tarp, Sven

    2009-01-01

    of languages include books and papers on the development of theories and principles for the compilation of dictionaries as well as reviews of dictionaries and monographs in a constant quest to learn from other scholars. The dictionaries he has authored and co-authored cover the spectrum from monolingual...... contributed to research and therefore influenced both national and international research communities. Not only has Henning Bergenholtz published theoretical works on lexicography and other topics, but he is also the author and co-author of a range of dictionaries. His theoretical publications in a variety...... general dictionaries to bilingual specialised dictionaries with languages such as Danish, Dutch, English, Malagasy and Spanish within fields as diverse as microbiology and accounting. In addition, he has been the editor of several books and academic journals, e.g. Hermes and LexicoNordica (he is one...

  9. 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.

  10. Evolution under domestication: ongoing artificial selection and divergence of wild and managed Stenocereus pruinosus (Cactaceae) populations in the Tehuacán Valley, Mexico

    Science.gov (United States)

    Parra, Fabiola; Casas, Alejandro; Peñaloza-Ramírez, Juan Manuel; Cortés-Palomec, Aurea C.; Rocha-Ramírez, Víctor; González-Rodríguez, Antonio

    2010-01-01

    Background and Aims The Tehuacán Valley in Mexico is a principal area of plant domestication in Mesoamerica. There, artificial selection is currently practised on nearly 120 native plant species with coexisting wild, silvicultural and cultivated populations, providing an excellent setting for studying ongoing mechanisms of evolution under domestication. One of these species is the columnar cactus Stenocereus pruinosus, in which we studied how artificial selection is operating through traditional management and whether it has determined morphological and genetic divergence between wild and managed populations. Methods Semi-structured interviews were conducted with 83 households of three villages to investigate motives and mechanisms of artificial selection. Management effects were studied by comparing variation patterns of 14 morphological characters and population genetics (four microsatellite loci) of 264 plants from nine wild, silvicultural and cultivated populations. Key Results Variation in fruit characters was recognized by most people, and was the principal target of artificial selection directed to favour larger and sweeter fruits with thinner or thicker peel, fewer spines and pulp colours others than red. Artificial selection operates in agroforestry systems favouring abundance (through not felling plants and planting branches) of the preferred phenotypes, and acts more intensely in household gardens. Significant morphological divergence between wild and managed populations was observed in fruit characters and plant vigour. On average, genetic diversity in silvicultural populations (HE = 0·743) was higher than in wild (HE = 0·726) and cultivated (HE = 0·700) populations. Most of the genetic variation (90·58 %) occurred within populations. High gene flow (NmFST > 2) was identified among almost all populations studied, but was slightly limited by mountains among wild populations, and by artificial selection among wild and managed populations. Conclusions

  11. Evolution under domestication: ongoing artificial selection and divergence of wild and managed Stenocereus pruinosus (Cactaceae) populations in the Tehuacan Valley, Mexico.

    Science.gov (United States)

    Parra, Fabiola; Casas, Alejandro; Peñaloza-Ramírez, Juan Manuel; Cortés-Palomec, Aurea C; Rocha-Ramírez, Víctor; González-Rodríguez, Antonio

    2010-09-01

    The Tehuacán Valley in Mexico is a principal area of plant domestication in Mesoamerica. There, artificial selection is currently practised on nearly 120 native plant species with coexisting wild, silvicultural and cultivated populations, providing an excellent setting for studying ongoing mechanisms of evolution under domestication. One of these species is the columnar cactus Stenocereus pruinosus, in which we studied how artificial selection is operating through traditional management and whether it has determined morphological and genetic divergence between wild and managed populations. Semi-structured interviews were conducted with 83 households of three villages to investigate motives and mechanisms of artificial selection. Management effects were studied by comparing variation patterns of 14 morphological characters and population genetics (four microsatellite loci) of 264 plants from nine wild, silvicultural and cultivated populations. Variation in fruit characters was recognized by most people, and was the principal target of artificial selection directed to favour larger and sweeter fruits with thinner or thicker peel, fewer spines and pulp colours other than red. Artificial selection operates in agroforestry systems favouring abundance (through not felling plants and planting branches) of the preferred phenotypes, and acts more intensely in household gardens. Significant morphological divergence between wild and managed populations was observed in fruit characters and plant vigour. On average, genetic diversity in silvicultural populations (H(E) = 0.743) was higher than in wild (H(E) = 0.726) and cultivated (H(E) = 0.700) populations. Most of the genetic variation (90.58 %) occurred within populations. High gene flow (Nm(FST) > 2) was identified among almost all populations studied, but was slightly limited by mountains among wild populations, and by artificial selection among wild and managed populations. Traditional management of S. pruinosus involves

  12. A genome-wide association study in a large F2-cross of laying hens reveals novel genomic regions associated with feather pecking and aggressive pecking behavior.

    Science.gov (United States)

    Lutz, Vanessa; Stratz, Patrick; Preuß, Siegfried; Tetens, Jens; Grashorn, Michael A; Bessei, Werner; Bennewitz, Jörn

    2017-02-03

    Feather pecking and aggressive pecking in laying hens are serious economic and welfare issues. In spite of extensive research on feather pecking during the last decades, the motivation for this behavior is still not clear. A small to moderate heritability has frequently been reported for these traits. Recently, we identified several single-nucleotide polymorphisms (SNPs) associated with feather pecking by mapping selection signatures in two divergent feather pecking lines. Here, we performed a genome-wide association analysis (GWAS) for feather pecking and aggressive pecking behavior, then combined the results with those from the recent selection signature experiment, and linked them to those obtained from a differential gene expression study. A large F2 cross of 960 F2 hens was generated using the divergent lines as founders. Hens were phenotyped for feather pecks delivered (FPD), aggressive pecks delivered (APD), and aggressive pecks received (APR). Individuals were genotyped with the Illumina 60K chicken Infinium iSelect chip. After data filtering, 29,376 SNPs remained for analyses. Single-marker GWAS was performed using a Poisson model. The results were combined with those from the selection signature experiment using Fisher's combined probability test. Numerous significant SNPs were identified for all traits but with low false discovery rates. Nearly all significant SNPs were located in clusters that spanned a maximum of 3 Mb and included at least two significant SNPs. For FPD, four clusters were identified, which increased to 13 based on the meta-analysis (FPD meta ). Seven clusters were identified for APD and three for APR. Eight genes (of the 750 investigated genes located in the FPD meta clusters) were significantly differentially-expressed in the brain of hens from both lines. One gene, SLC12A9, and the positional candidate gene for APD, GNG2, may be linked to the monomanine signaling pathway, which is involved in feather pecking and aggressive behavior

  13. Characterization and Profiling of Liver microRNAs by RNA-sequencing in Cattle Divergently Selected for Residual Feed Intake

    Directory of Open Access Journals (Sweden)

    Wijdan Al-Husseini

    2016-10-01

    Full Text Available MicroRNAs (miRNAs are short non-coding RNAs that post-transcriptionally regulate expression of mRNAs in many biological pathways. Liver plays an important role in the feed efficiency of animals and high and low efficient cattle demonstrated different gene expression profiles by microarray. Here we report comprehensive miRNAs profiles by next-gen deep sequencing in Angus cattle divergently selected for residual feed intake (RFI and identify miRNAs related to feed efficiency in beef cattle. Two microRNA libraries were constructed from pooled RNA extracted from livers of low and high RFI cattle, and sequenced by Illumina genome analyser. In total, 23,628,103 high quality short sequence reads were obtained and more than half of these reads were matched to the bovine genome (UMD 3.1. We identified 305 known bovine miRNAs. Bta-miR-143, bta-miR-30, bta-miR-122, bta-miR-378, and bta-let-7 were the top five most abundant miRNAs families expressed in liver, representing more than 63% of expressed miRNAs. We also identified 52 homologous miRNAs and 10 novel putative bovine-specific miRNAs, based on precursor sequence and the secondary structure and utilizing the miRBase (v. 21. We compared the miRNAs profile between high and low RFI animals and ranked the most differentially expressed bovine known miRNAs. Bovine miR-143 was the most abundant miRNA in the bovine liver and comprised 20% of total expressed mapped miRNAs. The most highly expressed miRNA in liver of mice and humans, miR-122, was the third most abundant in our cattle liver samples. We also identified 10 putative novel bovine-specific miRNA candidates. Differentially expressed miRNAs between high and low RFI cattle were identified with 18 miRNAs being up-regulated and 7 other miRNAs down-regulated in low RFI cattle. Our study has identified comprehensive miRNAs expressed in bovine liver. Some of the expressed miRNAs are novel in cattle. The differentially expressed miRNAs between high and low RFI

  14. 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.

  15. Welfare indicators in laying hens in relation to nest exclusion

    DEFF Research Database (Denmark)

    Alm, M; Tauson, R; Holm, L

    2016-01-01

    Consumer concerns about the welfare of laying hens are increasing, leading to increased interest in identifying reliable ways to assess welfare. The present study evaluated invasive and non-invasive welfare indicators in relation to a stressful challenge. The study included 126 Lohmann Selected...

  16. Diverging Cohesion?

    DEFF Research Database (Denmark)

    Charron, Nicholas

    2016-01-01

    – which we define here as a combination of impartial bureaucratic practices, corruption and the rule of law – limits, and in some cases reverses the tendency towards greater divergence linked to trade. Countries with high levels of state capacity – that is, those that have greater government effectiveness......, stronger rule of law and lower corruption – experience lower levels of divergence, as they have the mechanisms to counterbalance the strong centripetal forces linked to openness. This claim is tested on countries that have experienced relatively high levels of increases in levels of economic and political......Why do increases in globalisation in the face of European expansion lead to sharp levels of regional divergences in wealth in some countries but not in others? The central crux of this paper is that convergence/divergence trends in European states are conditioned by ‘state capacity’. State capacity...

  17. Extreme MHC class I diversity in the sedge warbler (Acrocephalus schoenobaenus); selection patterns and allelic divergence suggest that different genes have different functions.

    Science.gov (United States)

    Biedrzycka, Aleksandra; O'Connor, Emily; Sebastian, Alvaro; Migalska, Magdalena; Radwan, Jacek; Zając, Tadeusz; Bielański, Wojciech; Solarz, Wojciech; Ćmiel, Adam; Westerdahl, Helena

    2017-07-05

    Recent work suggests that gene duplications may play an important role in the evolution of immunity genes. Passerine birds, and in particular Sylvioidea warblers, have highly duplicated major histocompatibility complex (MHC) genes, which are key in immunity, compared to other vertebrates. However, reasons for this high MHC gene copy number are yet unclear. High-throughput sequencing (HTS) allows MHC genotyping even in individuals with extremely duplicated genes. This HTS data can reveal evidence of selection, which may help to unravel the putative functions of different gene copies, i.e. neofunctionalization. We performed exhaustive genotyping of MHC class I in a Sylvioidea warbler, the sedge warbler, Acrocephalus schoenobaenus, using the Illumina MiSeq technique on individuals from a wild study population. The MHC diversity in 863 genotyped individuals by far exceeds that of any other bird species described to date. A single individual could carry up to 65 different alleles, a large proportion of which are expressed (transcribed). The MHC alleles were of three different lengths differing in evidence of selection, diversity and divergence within our study population. Alleles without any deletions and alleles containing a 6 bp deletion showed characteristics of classical MHC genes, with evidence of multiple sites subject to positive selection and high sequence divergence. In contrast, alleles containing a 3 bp deletion had no sites subject to positive selection and had low divergence. Our results suggest that sedge warbler MHC alleles that either have no deletion, or contain a 6 bp deletion, encode classical antigen presenting MHC molecules. In contrast, MHC alleles containing a 3 bp deletion may encode molecules with a different function. This study demonstrates that highly duplicated MHC genes can be characterised with HTS and that selection patterns can be useful for revealing neofunctionalization. Importantly, our results highlight the need to consider the

  18. 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

  19. 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 ...

  20. 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

  1. Effect of heterogeneity of nest boxes on occurrence of gregarious nesting in laying hens

    DEFF Research Database (Denmark)

    Clausen, Tina; Riber, Anja Brinch

    2012-01-01

    Gregarious nesting, where hens select already occupied nest boxes even when other nest boxes are unoccupied, is an unwanted behaviour in laying hens that may reduce animal welfare and pose a financial cost to the producer. It has been suggested that gregarious nesting is caused by the difficulties...... nesting was higher in experimental groups compared to control groups (P right were higher compared to nest boxes positioned...

  2. Comparison of two different breeding systems laying hens in relation to egg shell quality, II

    OpenAIRE

    Mária Angelovičová; Viera Ševčíková; Marek Angelovič; Ondřej Bučko

    2014-01-01

    The aim of work was to follow up and statistically evaluate the selected quality indicators of egg shell according to two different breeding systems and different age of laying hens. An object of investigation were shell weight, share of the shell, strength and thickness of the shell for table eggs. There were used the laying hens of final hybrid ISA Brown reared in enriched cage system, and free range system. In both breeding systems were ensured the conditions with application of the welfar...

  3. Genetic analysis of a divergent selection for resistance to Rous sarcomas in chickens†. This article is dedicated to the memory of Pierrick Thoraval (1960–2000.

    Directory of Open Access Journals (Sweden)

    Dambrine Ginette

    2004-01-01

    Full Text Available Abstract Selection for disease resistance related traits is a tool of choice for evidencing and exploring genetic variability and studying underlying resistance mechanisms. In this framework, chickens originating from a base population, homozygote for the B19 major histocompatibility complex (MHC were divergently selected for either progression or regression of tumors induced at 4 weeks of age by a SR-D strain of Rous sarcoma virus (RSV. The first generation of selection was based on a progeny test and subsequent selections were performed on full-sibs. Data of 18 generations including a total of 2010 birds measured were analyzed for the tumor profile index (TPI, a synthetic criterion of resistance derived from recording the volume of the tumors and mortality. Response to selection and heritability of TPI were estimated using a restricted maximum likelihood method with an animal model. Significant progress was shown in both directions: the lines differing significantly for TPI and mortality becoming null in the "regressor" line. Heritability of TPI was estimated as 0.49 ± 0.05 and 0.53 ± 0.06 within the progressor and regressor lines respectively, and 0.46 ± 0.03 when estimated over lines. Preliminary results showed within the progressor line a possible association between one Rfp-Y type and the growth of tumors.

  4. Effects of asymmetric nuclear introgression, introgressive mitochondrial sweep, and purifying selection on phylogenetic reconstruction and divergence estimates in the Pacific clade of Locustella warblers.

    Science.gov (United States)

    Drovetski, Sergei V; Semenov, Georgy; Red'kin, Yaroslav A; Sotnikov, Vladimir N; Fadeev, Igor V; Koblik, Evgeniy A

    2015-01-01

    When isolated but reproductively compatible populations expand geographically and meet, simulations predict asymmetric introgression of neutral loci from a local to invading taxon. Genetic introgression may affect phylogenetic reconstruction by obscuring topology and divergence estimates. We combined phylogenetic analysis of sequences from one mtDNA and 12 nuDNA loci with analysis of gene flow among 5 species of Pacific Locustella warblers to test for presence of genetic introgression and its effects on tree topology and divergence estimates. Our data showed that nuDNA introgression was substantial and asymmetrical among all members of superspecies groups whereas mtDNA showed no introgression except a single species pair where the invader's mtDNA was swept by mtDNA of the local species. This introgressive sweep of mtDNA had the opposite direction of the nuDNA introgression and resulted in the paraphyly of the local species' mtDNA haplotypes with respect to those of the invader. Тhe multilocus nuDNA species tree resolved all inter- and intraspecific relationships despite substantial introgression. However, the node ages on the species tree may be underestimated as suggested by the differences in node age estimates based on non-introgressing mtDNA and introgressing nuDNA. In turn, the introgressive sweep and strong purifying selection appear to elongate internal branches in the mtDNA gene tree.

  5. Divergent stress responses and coping styles in psychogenetically selected Roman high-(RHA) and low-(RLA) avoidance rats: behavioural, neuroendocrine and developmental aspects.

    Science.gov (United States)

    Steimer, Thierry; Driscoll, Peter

    2003-06-01

    The Swiss sublines of Roman high-(RHA/Verh) and low-(RLA/Verh) avoidance rats have been genetically selected for good vs. poor performance in two-way active avoidance since 1972. RLA/Verh rats show increased stress responses (e.g. freezing behaviour, ACTH, corticosterone and prolactin secretion) and adopt a more passive (or reactive) coping style when confronted with a novel environment. In the open field, elevated plus-maze, black/white box test, and in a new light/dark open field test, RLA/Verh rats appear to be more anxious than their RHA/Verh counterparts. Anxiety may result from their particular psychophysiological profile, i.e. increased emotionality combined with a passive coping style. In contrast, RHA/Verh rats are less responsive to stress, they show little anxiety in novel situations and tend to be impulsive and novelty (sensation) seekers. Some behavioural differences are already noticeable shortly after birth, but the full pattern appears to stabilize only after puberty. Gene-environment interactions are critical in establishing this pattern. The data reviewed indicate that the differences between RHA/Verh and RLA/Verh rats probably result from a complex interaction among divergent anxiety/emotionality characteristics, differences in locomotor activity and novelty/reward seeking, as well as active vs. passive coping styles. It is proposed further that these divergent personality types are to be found not only in other selective breeding programs but in the form of individual differences in most populations of rats used for this type of research.

  6. Natural selection drives the fine-scale divergence of a coevolutionary arms race involving a long-mouthed weevil and its obligate host plant

    Directory of Open Access Journals (Sweden)

    Toju Hirokazu

    2009-01-01

    Full Text Available Abstract Background One of the major recent advances in evolutionary biology is the recognition that evolutionary interactions between species are substantially differentiated among geographic populations. To date, several authors have revealed natural selection pressures mediating the geographically-divergent processes of coevolution. How local, then, is the geographic structuring of natural selection in coevolutionary systems? Results I examined the spatial scale of a "geographic selection mosaic," focusing on a system involving a seed-predatory insect, the camellia weevil (Curculio camelliae, and its host plant, the Japanese camellia (Camellia japonica. In this system, female weevils excavate camellia fruits with their extremely-long mouthparts to lay eggs into seeds, while camellia seeds are protected by thick pericarps. Quantitative evaluation of natural selection demonstrated that thicker camellia pericarps are significantly favored in some, but not all, populations within a small island (Yakushima Island, Japan; diameter ca. 30 km. At the extreme, camellia populations separated by only several kilometers were subject to different selection pressures. Interestingly, in a population with the thickest pericarps, camellia individuals with intermediate pericarp thickness had relatively high fitness when the potential costs of producing thick pericarps were considered. Also importantly, some parameters of the weevil - camellia interaction such as the severity of seed infestation showed clines along temperature, suggesting the effects of climate on the fine-scale geographic differentiation of the coevolutionary processes. Conclusion These results show that natural selection can drive the geographic differentiation of interspecific interactions at surprisingly small spatial scales. Future studies should reveal the evolutionary/ecological outcomes of the "fine scale geographic mosaics" in biological communities.

  7. Comparison of two different breeding systems laying hens in relation to egg shell quality, II

    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 selected quality indicators of egg shell according to two different breeding systems and different age of laying hens. An object of investigation were shell weight, share of the shell, strength and thickness of the shell for table eggs. There were used the laying hens of final hybrid ISA Brown reared in enriched cage system, and free range system. In both breeding systems were ensured the conditions with application of the welfare principles. There was used to feed a complete feed mixture HYD 10 in the both breeding systems.  The feeders were supplemented with feed by hand, daily and the same day was supplemented water to drinking troughs. Egg collection was hand in both breeding systems. This paper is a contribution to the solution of optimal breeding laying hens and production of high quality and safe production of table eggs. From the evaluation of the results was formulated conclusion, which shows that statistically significant (p ≤ 0.05 higher egg shell thickness was observed in the breeding free range system compared to the thickness of the egg shell in the breeding cage system, and in age 40 weeks of laying hens in both breeding systems compared to the thickness of the egg shell in age 30 weeks of laying hens. No statistically significant difference (p ≥ 0.05 was observed in egg shell weight between breeding cage system and free range system. Statistically significant (p ≤ 0.05 higher egg shell weight was observed in the age 40 weeks of laying hens in both breeding  systems compared to age 30 weeks of laying hens. There no statistically significant difference (p ≥ 0.05 was observed in the share of egg shell and egg shell strength between breeding cage system and free range system, nor between age 30 and 40 weeks of laying hens.

  8. 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.

  9. Effects of phytoestrogen supplementation in the feed on the shell gland of laying hens at the end of the laying period.

    Science.gov (United States)

    Wistedt, A; Ridderstråle, Y; Wall, H; Holm, L

    2012-08-01

    Shell quality decreases as laying hens age and the aim of present study was to investigate how a supplement of daidzein, a natural phytoestrogen in soya, affects key factors in the shell gland and eggshell quality in late-stage laying hens. Hybrids of Lohmann Selected Leghorn (LSL) and Lohmann Brown (LB), received either a daidzein diet (50 mg/kg feed) or a control diet from 60 to 72 weeks of age. Both the total number of capillaries and capillaries with carbonic anhydrase (CA) activity were higher in the LSL hybrid than in the LB. After daidzein supplementation the number of CA positive capillaries was unaffected in the LSL but increased in the LB hybrid indicating a higher sensitivity to daidzein in this hybrid. Estrogen receptor alpha and beta (ERα, ERβ) were localized and the complete picture of the two ERs can now be described in shell gland of domestic hens. Nuclear and cytoplasmic staining was generally stronger for ERβ, while membrane associated staining was present only for ERα. Interestingly, capillary endothelium contained only ERβ and since estrogen regulation of CA is well documented, the presence of an endothelial ER provides one possible route for the increase in CA positive capillaries found in LB hybrids. Eggshell quality or egg production was not affected by daidzein supplementation. The hybrids used in this study showed anatomical differences and reacted differently to daidzein supplementation, but if this can be explained by the divergences in ERβ localization noted between the hybrids remains to be clarified. Copyright © 2012 Elsevier B.V. All rights reserved.

  10. Nonlinear selection and a blend of convergent, divergent and parallel evolution shapes natural variation in glucosinolates

    DEFF Research Database (Denmark)

    Kliebenstein, Daniel James; Cacho, N. Ivalú

    2016-01-01

    and traits that is highly similar both within and between species. Further, early field trials with single gene recreations of natural variation are showing that selection is highly fluctuating both from site to site and from year to year within a location. This review goes into the specific ecological......The molecular mechanisms underlying organismal fitness in complex environments is just beginning to be illuminated. One of the pre-eminent model systems that span the molecular to field fitness chasm is the natural variation in glucosinolate defence metabolites within the Capparales. In this system......, evolutionary and molecular observations for each of the major loci controlling natural variation in glucosinolates....

  11. Heritability of body surface temperature in hens estimated by infrared thermography at normal or hot temperatures and genetic correlations with egg and feather quality

    NARCIS (Netherlands)

    Loyau, T.; Zerjal, T.; Rodenburg, T.B.; Fablet, J.; Tixier-Boichard, M.; Pinard-van der Laan, M.H.; Mignon-Grasteau, S.

    2016-01-01

    Exposure of laying hens to chronic heat stress results in loss of egg production. It should be possible to improve hen resilience to chronic heat stress by genetic selection but measuring their sensitivity through internal temperature is time consuming and is not very precise. In this study we

  12. Phenotypic flexibility of traits related to energy acquisition in mice divergently selected for basal metabolic rate (BMR).

    Science.gov (United States)

    Ksiazek, Aneta; Czerniecki, Jan; Konarzewski, Marek

    2009-03-01

    Theoretical considerations suggest that one of the main factors determining phenotypic flexibility of the digestive system is the size (mass) of internal organs. To test this, we used mice from two lines selected for high and low levels of basal metabolic rate (BMR). Mice with higher BMRs also have larger internal organs and higher daily food consumption (C) under non-stressful conditions. We exposed animals from both lines to a sudden cold exposure by transferring them (without prior acclimation) from an ambient temperature of 23 degrees C to 5 degrees C. Cold exposure elicited a twofold increase in C and a 25% reduction of apparent digestive efficiency. For the same body mass-corrected C, small intestine, kidneys, heart and liver of cold-exposed low-BMR mice were smaller than those of the high-BMR line. Therefore, the internal organs of low-BMR animals were burdened with substantially higher metabolic loads (defined as C or digestible food intake per total mass of a particular organ). The mass-specific activity of citrate synthase (CS) in the liver and kidneys (but not heart) was also lower in the low-BMR mice. The magnitude of phenotypic flexibility of internal organ size and CS activity was strictly proportional to the organ mass (in the case of kidneys and liver, also mass-specific CS activity) prior to an increased energy demand. Thus, phenotypic flexibility had additive rather than multiplicative dynamics. Our results also suggest that variation in BMR positively correlates with the magnitude of an immediate spare capacity that fuels the initial response of internal organs to a sudden metabolic stress.

  13. 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.

  14. Genetic characterization of a core collection of flax (Linum usitatissimum L.) suitable for association mapping studies and evidence of divergent selection between fiber and linseed types.

    Science.gov (United States)

    Soto-Cerda, Braulio J; Diederichsen, Axel; Ragupathy, Raja; Cloutier, Sylvie

    2013-05-06

    Flax is valued for its fiber, seed oil and nutraceuticals. Recently, the fiber industry has invested in the development of products made from linseed stems, making it a dual purpose crop. Simultaneous targeting of genomic regions controlling stem fiber and seed quality traits could enable the development of dual purpose cultivars. However, the genetic diversity, population structure and linkage disequilibrium (LD) patterns necessary for association mapping (AM) have not yet been assessed in flax because genomic resources have only recently been developed. We characterized 407 globally distributed flax accessions using 448 microsatellite markers. The data was analyzed to assess the suitability of this core collection for AM. Genomic scans to identify candidate genes selected during the divergent breeding process of fiber flax and linseed were conducted using the whole genome shotgun sequence of flax. Combined genetic structure analysis assigned all accessions to two major groups with six sub-groups. Population differentiation was weak between the major groups (F(ST) = 0.094) and for most of the pairwise comparisons among sub-groups. The molecular coancestry analysis indicated weak relatedness (mean = 0.287) for most individual pairs. Abundant genetic diversity was observed in the total panel (5.32 alleles per locus), and some sub-groups showed a high proportion of private alleles. The average genome-wide LD (r²) was 0.036, with a relatively fast decay of 1.5 cM. Genomic scans between fiber flax and linseed identified candidate genes involved in cell-wall biogenesis/modification, xylem identity and fatty acid biosynthesis congruent with genes previously identified in flax and other plant species. Based on the abundant genetic diversity, weak population structure and relatedness and relatively fast LD decay, we concluded that this core collection is suitable for AM studies targeting multiple agronomic and quality traits aiming at the improvement of flax as a

  15. A quantitative and efficient approach to select MIRU-VNTR loci based on accumulation of the percentage differences of strains for discriminating divergent Mycobacterium tuberculosis sublineages.

    Science.gov (United States)

    Pan, Xin-Ling; Zhang, Chun-Lei; Nakajima, Chie; Fu, Jin; Shao, Chang-Xia; Zhao, Li-Na; Cui, Jia-Yi; Jiao, Na; Fan, Chang-Long; Suzuki, Yasuhiko; Hattori, Toshio; Li, Di; Ling, Hong

    2017-07-26

    Although several optimal mycobacterial interspersed repetitive units-variable number tandem repeat (MIRU-VNTR) loci have been suggested for genotyping homogenous Mycobacterium tuberculosis, including the Beijing genotype, a more efficient and convenient selection strategy for identifying optimal VNTR loci is needed. Here 281 M. tuberculosis isolates were analyzed. Beijing genotype and non-Beijing genotypes were identified, as well as Beijing sublineages, according to single nucleotide polymorphisms. A total of 22 MIRU-VNTR loci were used for genotyping. To efficiently select optimal MIRU-VNTR loci, we established accumulations of percentage differences (APDs) between the strains among the different genotypes. In addition, we constructed a minimum spanning tree for clustering analysis of the VNTR profiles. Our findings showed that eight MIRU-VNTR loci displayed disparities in h values of ≥0.2 between the Beijing genotype and non-Beijing genotype isolates. To efficiently discriminate Beijing and non-Beijing genotypes, an optimal VNTR set was established by adding loci with APDs ranging from 87.2% to 58.8%, resulting in the construction of a nine-locus set. We also found that QUB11a is a powerful locus for separating ST10s (including ST10, STF and STCH1) and ST22s (including ST22 and ST8) strains, whereas a combination of QUB11a, QUB4156, QUB18, Mtub21 and QUB26 could efficiently discriminate Beijing sublineages. Our findings suggested that two nine-locus sets were not only efficient for distinguishing the Beijing genotype from non-Beijing genotype strains, but were also suitable for sublineage genotyping with different discriminatory powers. These results indicate that APD represents a quantitative and efficient approach for selecting MIRU-VNTR loci to discriminate between divergent M. tuberculosis sublineages.

  16. A quantitative and efficient approach to select MIRU–VNTR loci based on accumulation of the percentage differences of strains for discriminating divergent Mycobacterium tuberculosis sublineages

    Science.gov (United States)

    Pan, Xin-Ling; Zhang, Chun-Lei; Nakajima, Chie; Fu, Jin; Shao, Chang-Xia; Zhao, Li-Na; Cui, Jia-Yi; Jiao, Na; Fan, Chang-Long; Suzuki, Yasuhiko; Hattori, Toshio; Li, Di; Ling, Hong

    2017-01-01

    Although several optimal mycobacterial interspersed repetitive units–variable number tandem repeat (MIRU–VNTR) loci have been suggested for genotyping homogenous Mycobacterium tuberculosis, including the Beijing genotype, a more efficient and convenient selection strategy for identifying optimal VNTR loci is needed. Here 281 M. tuberculosis isolates were analyzed. Beijing genotype and non-Beijing genotypes were identified, as well as Beijing sublineages, according to single nucleotide polymorphisms. A total of 22 MIRU–VNTR loci were used for genotyping. To efficiently select optimal MIRU–VNTR loci, we established accumulations of percentage differences (APDs) between the strains among the different genotypes. In addition, we constructed a minimum spanning tree for clustering analysis of the VNTR profiles. Our findings showed that eight MIRU–VNTR loci displayed disparities in h values of ≥0.2 between the Beijing genotype and non-Beijing genotype isolates. To efficiently discriminate Beijing and non-Beijing genotypes, an optimal VNTR set was established by adding loci with APDs ranging from 87.2% to 58.8%, resulting in the construction of a nine-locus set. We also found that QUB11a is a powerful locus for separating ST10s (including ST10, STF and STCH1) and ST22s (including ST22 and ST8) strains, whereas a combination of QUB11a, QUB4156, QUB18, Mtub21 and QUB26 could efficiently discriminate Beijing sublineages. Our findings suggested that two nine-locus sets were not only efficient for distinguishing the Beijing genotype from non-Beijing genotype strains, but were also suitable for sublineage genotyping with different discriminatory powers. These results indicate that APD represents a quantitative and efficient approach for selecting MIRU–VNTR loci to discriminate between divergent M. tuberculosis sublineages. PMID:28745309

  17. Identification of differentially expressed genes in the oviduct of two rabbit lines divergently selected for uterine capacity using suppression subtractive hybridization.

    Science.gov (United States)

    Ballester, M; Castelló, A; Peiró, R; Argente, M J; Santacreu, M A; Folch, J M

    2013-06-01

    Suppressive subtractive hybridization libraries from oviduct at 62 h post-mating of two lines of rabbits divergently selected for uterine capacity were generated to identify differentially expressed genes. A total of 438 singletons and 126 contigs were obtained by cluster assembly and sequence alignment of 704 expressed sequence tags (ESTs), of which 54% showed homology to known proteins of the non-redundant NCBI databases. Differential screening by dot blot validated 71 ESTs, of which 47 showed similarity to known genes. Transcripts of genes were functionally annotated in the molecular function and the biological process gene ontology categories using the BLAST2GO software and were assigned to reproductive developmental process, immune response, amino acid metabolism and degradation, response to stress and apoptosis terms. Finally, three interesting genes, PGR, HSD17B4 and ERO1L, were identified as overexpressed in the low line using RT-qPCR. Our study provides a list of candidate genes that can be useful to understanding the molecular mechanisms underlying the phenotypic differences observed in early embryo survival and development traits. © 2012 The Authors, Animal Genetics © 2012 Stichting International Foundation for Animal Genetics.

  18. Mapping quantitative trait loci affecting fatness and breast muscle weight in meat-type chicken lines divergently selected on abdominal fatness

    Directory of Open Access Journals (Sweden)

    Neau André

    2006-01-01

    Full Text Available Abstract Quantitative trait loci (QTL for abdominal fatness and breast muscle weight were investigated in a three-generation design performed by inter-crossing two experimental meat-type chicken lines that were divergently selected on abdominal fatness. A total of 585 F2 male offspring from 5 F1 sires and 38 F1 dams were recorded at 8 weeks of age for live body, abdominal fat and breast muscle weights. One hundred-twenty nine microsatellite markers, evenly located throughout the genome and heterozygous for most of the F1 sires, were used for genotyping the F2 birds. In each sire family, those offspring exhibiting the most extreme values for each trait were genotyped. Multipoint QTL analyses using maximum likelihood methods were performed for abdominal fat and breast muscle weights, which were corrected for the effects of 8-week body weight, dam and hatching group. Isolated markers were assessed by analyses of variance. Two significant QTL were identified on chromosomes 1 and 5 with effects of about one within-family residual standard deviation. One breast muscle QTL was identified on GGA1 with an effect of 2.0 within-family residual standard deviation.

  19. '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)...

  20. Impact of divergent selection for ultimate pH of pectoralis major muscle on biochemical, histological, and sensorial attributes of broiler meat.

    Science.gov (United States)

    Alnahhas, N; Le Bihan-Duval, E; Baéza, E; Chabault, M; Chartrin, P; Bordeau, T; Cailleau-Audouin, E; Meteau, K; Berri, C

    2015-09-01

    The impact of divergent selection based on the ultimate pH (pHu) of pectoralis major (P. major) muscle on the chemical, biochemical, and histological profiles of the muscle and sensorial quality of meat was investigated in broiler chickens. The protein, lipid, DM, glycogen and lactate content, glycolytic potential, proteolysis, lipid and protein oxidation index, muscle fiber cross-sectional area, capillary density, and collagen surface were determined on the breast P. major muscle of 6-wk-old broilers issued from the high-pHu (pHu+) and low-pHu (pHu-) lines. Sensory attributes were also evaluated on the breast (roasted or grilled) and thigh (roasted) meat of the 2 lines. Protein, lipid, and DM content of P. major muscle were not affected by selection ( > 0.05). However, the P. major muscle of the pHu+ line was characterized by lower residual glycogen (-16%; ≤ 0.001) and lactate (-14%; ≤ 0.001) content and lower glycolytic potential (-14%; ≤ 0.001) compared with the pHu- line. Although the average cross-sectional area of muscle fibers and surface occupied by collagen were similar ( > 0.05) in both lines, fewer capillaries per fiber (-15%; ≤ 0.05) were observed in the pHu+ line. The pHu+ line was also characterized by lower lipid oxidation (thiobarbituric acid reactive substance index: -23%; ≤ 0.05) but protein oxidation and proteolysis index were not different ( > 0.05) between the 2 lines. At the sensory level, selection on breast muscle pHu mainly affected the texture of grilled and roast breast meat, which was judged significantly more tender ( ≤ 0.001) in the pHu+ line, and the acid taste, which was less pronounced in the roasted breast meat of the pHu+ line ( ≤ 0.002). This study highlighted that selection based on pHu does not affect the chemical composition and structure of breast meat. However, by modifying muscle blood supply and glycogen turnover, it affects meat acidity and oxidant status, both of which are likely to contribute to the large

  1. improving performance of laying hens

    Directory of Open Access Journals (Sweden)

    A.P Sinurat

    2012-10-01

    Full Text Available A trial was conducted in order to study the effect of the supplementation of Avizyme 1500® (Danisco Animal Nutrition, Marlborough, UK on the performance of laying hens for one year. A control diet based on corn – soybean meal was formulated to meet nutrient requirement of ISA Brown laying hens. Two treatments, the control diet (C and C + 1000 g Avizyme/tonne diet were tested. Each diet was fed to 80 birds (20 replicates of 4 birds from 20 to 72 weeks of age, and performances of birds (feed intake, egg production, egg size, egg mass, feed conversion ratio, and egg quality were measured. All data were subject to analyses of variance following the t-test. Results showed that the addition of Avizyme 1500 to the feed reduced feed intake by 4% (P < 0.01, mortality by 75 % or from 15% to 3.75% (P < 0.01 and improved the feed conversion ratio by 3 % (P < 0.05. The high mortality of the control treatment (15% is explained by an E.coli infection that was observed following the post-mortem examination of dead birds. The egg production (HD and HH, egg size and egg mass however were not significantly affected by the Avizyme supplementation. Egg quality (HU, yolk colour score, yolk weight and shell thickness was not significantly affected by Avizyme supplementation. It can be concluded that the supplementation of 1000 g Avizyme /tonne of diet improved feed efficiency and this was mediated via a reduction in feed intake.

  2. 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.

  3. Effect of Different Levels of L-Carnitine on the Productive Performance, Egg Quality, Blood Parameters and Egg Yolk Cholesterol in Laying Hens

    Directory of Open Access Journals (Sweden)

    Kazemi-Fard M

    2015-12-01

    Full Text Available This experiment was conducted to investigate the effects of different levels of L-carnitine on productive performance, egg quality and blood parameters in laying hens. Forty-eight Hy-Line W-36 egg Layers were weighed at 90 weeks of age and randomly allocated into 16 cages (three hens per cage. Four dietary treatments were prepared by supplementing L-carnitine (0, 50, 100 and 150 mg/kg of diet to corn-soybean meal diet and offered ad libitum to hens. After two weeks of acclimatization, the eggs were weighed daily and feed intake as well as egg quality traits were measured biweekly. At the end of the experiment, two hens from each cage were selected to determine blood parameters and two eggs from each replicate were collected for cholesterol analysis. Results showed that L-carnitine supplementation at 100 and 150 mg/kg significantly increased egg production and egg mass, but decreased yolk cholesterol content. Laying hens receiving diet containing 50 mg/kg L-carnitine had significantly higher Hough unit, but lower progesterone than the hens fed control diet (P < 0.05. The results of this study showed that supplementing hens' diet with L-carnitine had beneficial effects on productive performance and decreased yolk cholesterol concentration; so it can be used as an effective supplement in the diet of laying hens.

  4. Effects of Divergent Selection Body Weight and the Quail Laying Eggs on some Physical and Mechanical Properties of Japanese Quail Eggs

    Directory of Open Access Journals (Sweden)

    mousareza baghani

    2016-08-01

    Full Text Available Introduction Breeding quail and quail egg industrial production because of the high nutritional value of these products has been developing these years. Considering the high demand and economical production, further development in the future is predicted. In order to design and effective utilization of the equipment for transportation, separation, packaging and storage, the physical and mechanical properties of quail eggs are needed. It is of great importance to study the factors which are influencing these properties. Strength of the shell is an important factor in determination of quail egg quality. Quail egg shell strength depends on several variables including specific gravity, egg weight and volume, shell thickness, weight and percentage of shell, hardness, breaking force, breaking energy, egg surface, farming conditions, type and species of birds, nutrition and geometric characteristics of eggs. Materials and Methods In this paper, initially in three phases, at 15 weeks, 19 weeks and 23 weeks, shell strength changes and physical properties of quail eggs on 90 quails during their first period of laying eggs were studied. Measured properties were included dimensions, weight, volume, specific gravity, shell thickness, weight and percentage of shell, breaking force, breaking energy, egg surface and some other properties. In the second part the effects of divergent selection for the bird’s body weight at four weeks of age on the quail eggs of fifth generation were studied. Measured properties were included dimensions, weight, volume, breaking force, breaking energy and some factors for direct and indirect measurement of strength of quail eggs. For direct measurement of the strength of eggshell of quail, two methods were employed: The first method was quasi-static compression test between two parallel plates of the universal testing machine and the second method was measuring specific gravity. In the first method, eggs were compressed between

  5. Transcriptional analysis of abdominal fat in chickens divergently selected on bodyweight at two ages reveals novel mechanisms controlling adiposity: validating visceral adipose tissue as a dynamic endocrine and metabolic organ.

    Science.gov (United States)

    Resnyk, C W; Carré, W; Wang, X; Porter, T E; Simon, J; Le Bihan-Duval, E; Duclos, M J; Aggrey, S E; Cogburn, L A

    2017-08-16

    Decades of intensive genetic selection in the domestic chicken (Gallus gallus domesticus) have enabled the remarkable rapid growth of today's broiler (meat-type) chickens. However, this enhanced growth rate was accompanied by several unfavorable traits (i.e., increased visceral fatness, leg weakness, and disorders of metabolism and reproduction). The present descriptive analysis of the abdominal fat transcriptome aimed to identify functional genes and biological pathways that likely contribute to an extreme difference in visceral fatness of divergently selected broiler chickens. We used the Del-Mar 14 K Chicken Integrated Systems microarray to take time-course snapshots of global gene transcription in abdominal fat of juvenile [1-11 weeks of age (wk)] chickens divergently selected on bodyweight at two ages (8 and 36 wk). Further, a RNA sequencing analysis was completed on the same abdominal fat samples taken from high-growth (HG) and low-growth (LG) cockerels at 7 wk, the age with the greatest divergence in body weight (3.2-fold) and visceral fatness (19.6-fold). Time-course microarray analysis revealed 312 differentially expressed genes (FDR ≤ 0.05) as the main effect of genotype (HG versus LG), 718 genes in the interaction of age and genotype, and 2918 genes as the main effect of age. The RNA sequencing analysis identified 2410 differentially expressed genes in abdominal fat of HG versus LG chickens at 7 wk. The HG chickens are fatter and over-express numerous genes that support higher rates of visceral adipogenesis and lipogenesis. In abdominal fat of LG chickens, we found higher expression of many genes involved in hemostasis, energy catabolism and endocrine signaling, which likely contribute to their leaner phenotype and slower growth. Many transcription factors and their direct target genes identified in HG and LG chickens could be involved in their divergence in adiposity and growth rate. The present analyses of the visceral fat transcriptome in

  6. 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 ...

  7. 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.

  8. 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...

  9. 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.

  10. 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.

  11. 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.

  12. String perturbation theory diverges

    International Nuclear Information System (INIS)

    Gross, D.J.; Periwal, V.

    1988-01-01

    We prove that perturbation theory for the bosonic string diverges for arbitrary values of the coupling constant and is not Borel summable. This divergence is independent of the existence of the infinities that occur in the theory due to the presence of tachyons and dilaton tadpoles. We discuss the physical implications of such a divergence

  13. 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.

  14. 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.

  15. Genetic correlations between behavioural responses and performance traits in laying hens

    Directory of Open Access Journals (Sweden)

    Iwona Rozempolska-Rucińska

    2017-12-01

    they were positive but exhibited a substantial standard error, as for the egg weight. Conclusion To sum up the results obtained, it can be noted that behavioural responses indicating fearfulness, i.e. escape, avoidance, and approach-avoidance may reflect negative emotions experienced by birds. The negative correlations with performance in the group of fearful hens may indirectly indicate a high level of stress in these birds, especially in the white-feathered birds, where stronger performance-fearfulness correlations were found. Fearful birds should be eliminated from breeding by inclusion of the behavioural profile in the selection criterion in the case of laying hens.

  16. 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.

  17. Domination versus disjunctive domination in graphs | Henning ...

    African Journals Online (AJOL)

    Domination versus disjunctive domination in graphs. Michael A Henning, Sinclair A Marcon. Abstract. A dominating set in a graph G is a set S of vertices of G such that every vertex not in S is adjacent to a vertex of S. The domination number of G is the minimum cardinality of a dominating set of G. For a positive integer b, ...

  18. EFFICACY OF PROBIOTICS INTAKE ON INTERNAL MILIEU OF HENS

    Directory of Open Access Journals (Sweden)

    Martin Mellen

    2014-12-01

    Full Text Available The aim of present study was to evaluate the functional efficiency of probiotic preparation on selected blood biochemical parameters of ISA Brown hens. Feed in the experimental group of hens was enriched with a probiotic preparation in the dose of 500g.t-1 consisted of freeze-dried cultures: Lactobacillus bulgaricus LAT 187, L. acidophilus LAT 180, L. helveticus LAT 179, L. delbrueckii ssp. Lactis LAT 182, Streptococcus thermophiles LAT 205, Enterococcus faecium E-253 with concentration of 5.109 (CFU LAB living organisms in 1 gram. Blood samples were collected in 25 and 48 week of hens’ age. Biochemical parameters of mineral profile (calcium, phosphorus, magnesium, sodium, potassium, chlorides, energetic profile (plasma total cholesterol, triglycerides, total proteins, bilirubin, glucose, and activities of serum liver enzymes (aspartate aminotransferase AST, alanine aminotransferase ALT, alkaline phosphatase ALP were analysed using Ecoline kits and a semi-automated clinical chemistry analyser Microlab 300 (Vilat Scientific, Dieren, The Nederland. Probiotic preparation reduced (P<0.05 serum cholesterol and triglycerides content. No significant effects of probiotic on remaining parameters were confirmed.

  19. 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

  20. 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.

  1. Association of Egg Mass and Egg Sex: Gene Expression Analysis from Maternal RNA in the Germinal Disc Region of Layer Hens (Gallus gallus).

    Science.gov (United States)

    Aslam, Muhammad Aamir; Schokker, Dirkjan; Groothuis, Ton G G; de Wit, Agnes A C; Smits, Mari A; Woelders, Henri

    2015-06-01

    Female birds have been shown to manipulate offspring sex ratio. However, mechanisms of sex ratio bias are not well understood. Reduced feed availability and change in body condition can affect the mass of eggs in birds that could lead to a skew in sex ratio. We employed feed restriction in laying chickens (Gallus gallus) to induce a decrease in body condition and egg mass using 45 chicken hens in treatment and control groups. Feed restriction led to an overall decline of egg mass. In the second period of treatment (Days 9-18) with more severe feed restriction and a steeper decline of egg mass, the sex ratio per hen (proportion of male eggs) had a significant negative association with mean egg mass per hen. Based on this association, two groups of hens were selected from feed restriction group, that is, hens producing male bias with low egg mass and hens producing female bias with high egg mass with overall sex ratios of 0.71 and 0.44 respectively. Genomewide transcriptome analysis on the germinal disks of F1 preovulatory follicles collected at the time of occurrence of meiosis-I was performed. We did not find significantly differentially expressed genes in these two groups of hens. However, gene set enrichment analysis showed that a number of cellular processes related to cell cycle progression, mitotic/meiotic apparatus, and chromosomal movement were enriched in female-biased hens or high mean egg mass as compared with male-biased hens or low mean egg mass. The differentially expressed gene sets may be involved in meiotic drive regulating sex ratio in the chicken. © 2015 by the Society for the Study of Reproduction, Inc.

  2. The Patchwork Divergence Theorem

    OpenAIRE

    Dray, Tevian; Hellaby, Charles

    1994-01-01

    The divergence theorem in its usual form applies only to suitably smooth vector fields. For vector fields which are merely piecewise smooth, as is natural at a boundary between regions with different physical properties, one must patch together the divergence theorem applied separately in each region. We give an elegant derivation of the resulting "patchwork divergence theorem" which is independent of the metric signature in either region, and which is thus valid if the signature changes. (PA...

  3. Divergent Cumulative Cultural Evolution

    OpenAIRE

    Marriott, Chris; Chebib, Jobran

    2016-01-01

    Divergent cumulative cultural evolution occurs when the cultural evolutionary trajectory diverges from the biological evolutionary trajectory. We consider the conditions under which divergent cumulative cultural evolution can occur. We hypothesize that two conditions are necessary. First that genetic and cultural information are stored separately in the agent. Second cultural information must be transferred horizontally between agents of different generations. We implement a model with these ...

  4. 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 ...

  5. On infrared divergences

    International Nuclear Information System (INIS)

    Parisi, G.

    1979-01-01

    The structure of infrared divergences is studied in superrenormalizable interactions. It is conjectured that there is an extension of the Bogoliubov-Parasiuk-Hepp theorem which copes also with infrared divergences. The consequences of this conjecture on the singularities of the Borel transform in a massless asymptotic free field theory are discussed. The application of these ideas to gauge theories is briefly discussed. (Auth.)

  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. 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...

  8. 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...

  9. Phosphorus and phytase levels for layer hens

    OpenAIRE

    Juliana Cristina Ramos Rezende; Antonio Carlos de Laurentiz; Rosemeire da Silva Filardi; Vitor Barbosa Fascina; Daniella Aparecida Berto; Sérgio Turra Sobrane Filho

    2013-01-01

    The objective of this research was to evaluate the performance and bone quality of laying hens after peak production fed diets containing phosphorus levels and phytase. An experiment was conducted with 384 Hy-line distributed in a completely randomized in a factorial 4 x 3 with 4 levels of available phosphorus and 3 levels of phytase. The experimental period was divided into four periods of 28 days, at the end of each cycle were determined experimental feed intake, egg production, egg weight,...

  10. Distracting laying hens with a 'toy'

    African Journals Online (AJOL)

    use of a commercially available plastic device, intended to distract laying hens, was investigated and found not to have the claimed effect. ... table for the white birds, 15 week egg production. Source of variation df2. SS3. MS4. F ratio. SLs. East. Blocks. 35. 67627.61. 1932.22. Treatments. I. 1233.39. 1233.39. 0.7104. 0.4050.

  11. 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.

  12. 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.

  13. Quantum skew divergence

    Energy Technology Data Exchange (ETDEWEB)

    Audenaert, Koenraad M. R., E-mail: koenraad.audenaert@rhul.ac.uk [Department of Mathematics, Royal Holloway University of London, Egham TW20 0EX, United Kingdom and Department of Physics and Astronomy, University of Ghent, S9, Krijgslaan 281, B-9000 Ghent (Belgium)

    2014-11-15

    In this paper, we study the quantum generalisation of the skew divergence, which is a dissimilarity measure between distributions introduced by Lee in the context of natural language processing. We provide an in-depth study of the quantum skew divergence, including its relation to other state distinguishability measures. Finally, we present a number of important applications: new continuity inequalities for the quantum Jensen-Shannon divergence and the Holevo information, and a new and short proof of Bravyi's Small Incremental Mixing conjecture.

  14. Evaluation of Two Compressed Air Foam Systems for Culling Caged Layer Hens

    Directory of Open Access Journals (Sweden)

    Eric R. Benson

    2018-04-01

    Full Text Available Outbreaks of avian influenza (AI and other highly contagious poultry diseases continue to be a concern for those involved in the poultry industry. In the situation of an outbreak, emergency depopulation of the birds involved is necessary. In this project, two compressed air foam systems (CAFS were evaluated for mass emergency depopulation of layer hens in a manure belt equipped cage system. In both experiments, a randomized block design was used with multiple commercial layer hens treated with one of three randomly selected depopulation methods: CAFS, CAFS with CO2 gas, and CO2 gas. In Experiment 1, a Rowe manufactured CAFS was used, a selection of birds were instrumented, and the time to unconsciousness, brain death, altered terminal cardiac activity and motion cessation were recorded. CAFS with and without CO2 was faster to unconsciousness, however, the other parameters were not statistically significant. In Experiment 2, a custom Hale based CAFS was used to evaluate the impact of bird age, a selection of birds were instrumented, and the time to motion cessation was recorded. The difference in time to cessation of movement between pullets and spent hens using CAFS was not statistically significant. Both CAFS depopulate caged layers, however, there was no benefit to including CO2.

  15. Evaluation of Two Compressed Air Foam Systems for Culling Caged Layer Hens.

    Science.gov (United States)

    Benson, Eric R; Weiher, Jaclyn A; Alphin, Robert L; Farnell, Morgan; Hougentogler, Daniel P

    2018-04-24

    Outbreaks of avian influenza (AI) and other highly contagious poultry diseases continue to be a concern for those involved in the poultry industry. In the situation of an outbreak, emergency depopulation of the birds involved is necessary. In this project, two compressed air foam systems (CAFS) were evaluated for mass emergency depopulation of layer hens in a manure belt equipped cage system. In both experiments, a randomized block design was used with multiple commercial layer hens treated with one of three randomly selected depopulation methods: CAFS, CAFS with CO₂ gas, and CO₂ gas. In Experiment 1, a Rowe manufactured CAFS was used, a selection of birds were instrumented, and the time to unconsciousness, brain death, altered terminal cardiac activity and motion cessation were recorded. CAFS with and without CO₂ was faster to unconsciousness, however, the other parameters were not statistically significant. In Experiment 2, a custom Hale based CAFS was used to evaluate the impact of bird age, a selection of birds were instrumented, and the time to motion cessation was recorded. The difference in time to cessation of movement between pullets and spent hens using CAFS was not statistically significant. Both CAFS depopulate caged layers, however, there was no benefit to including CO₂.

  16. Evaluation of inbreeding in laying hens by applying optimum genetic contribution and gene flow theory.

    Science.gov (United States)

    König, S; Tsehay, F; Sitzenstock, F; von Borstel, U U; Schmutz, M; Preisinger, R; Simianer, H

    2010-04-01

    Due to consistent increases of inbreeding of on average 0.95% per generation in layer populations, selection tools should consider both genetic gain and genetic relationships in the long term. The optimum genetic contribution theory using official estimated breeding values for egg production was applied for 3 different lines of a layer breeding program to find the optimal allocations of hens and sires. Constraints in different scenarios encompassed restrictions related to additive genetic relationships, the increase of inbreeding, the number of selected sires and hens, and the number of selected offspring per mating. All these constraints enabled higher genetic gain up to 10.9% at the same level of additive genetic relationships or in lower relationships at the same gain when compared with conventional selection schemes ignoring relationships. Increases of inbreeding and genetic gain were associated with the number of selected sires. For the lowest level of the allowed average relationship at 10%, the optimal number of sires was 70 and the estimated breeding value for egg production of the selected group was 127.9. At the highest relationship constraint (16%), the optimal number of sires decreased to 15, and the average genetic value increased to 139.7. Contributions from selected sires and hens were used to develop specific mating plans to minimize inbreeding in the following generation by applying a simulated annealing algorithm. The additional reduction of average additive genetic relationships for matings was up to 44.9%. An innovative deterministic approach to estimate kinship coefficients between and within defined selection groups based on gene flow theory was applied to compare increases of inbreeding from random matings with layer populations undergoing selection. Large differences in rates of inbreeding were found, and they underline the necessity to establish selection tools controlling long-term relationships. Furthermore, it was suggested to use

  17. 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

  18. 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 ...

  19. 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

  20. 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

  1. 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 ...

  2. Selectivity and evolutionary divergence of metabotropic glutamate receptors for endogenous ligands and G proteins coupled to phospholipase C or TRP channels.

    Science.gov (United States)

    Kang, Hye Jin; Menlove, Kit; Ma, Jianpeng; Wilkins, Angela; Lichtarge, Olivier; Wensel, Theodore G

    2014-10-24

    To define the upstream and downstream signaling specificities of metabotropic glutamate receptors (mGluR), we have examined the ability of representative mGluR of group I, II, and III to be activated by endogenous amino acids and catalyze activation of G proteins coupled to phospholipase C (PLC), or activation of G(i/o) proteins coupled to the ion channel TRPC4β. Fluorescence-based assays have allowed us to observe interactions not previously reported or clearly identified. We have found that the specificity for endogenous amino acids is remarkably stringent. Even at millimolar levels, structurally similar compounds do not elicit significant activation. As reported previously, the clear exception is L-serine-O-phosphate (L-SOP), which strongly activates group III mGluR, especially mGluR4,-6,-8 but not group I or II mGluR. Whereas L-SOP cannot activate mGluR1 or mGluR2, it acts as a weak antagonist for mGluR1 and a potent antagonist for mGluR2, suggesting that co-recognition of L-glutamate and L-SOP arose early in evolution, and was followed later by divergence of group I and group II mGluR versus group III in l-SOP responses. mGluR7 has low affinity and efficacy for activation by both L-glutamate and L-SOP. Molecular docking studies suggested that residue 74 corresponding to lysine in mGluR4 and asparagine in mGluR7 might play a key role, and, indeed, mutagenesis experiments demonstrated that mutating this residue to lysine in mGluR7 enhances the potency of L-SOP. Experiments with pertussis toxin and dominant-negative Gα(i/o) proteins revealed that mGluR1 couples strongly to TRPC4β through Gα(i/o), in addition to coupling to PLC through Gα(q/11). © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. Selectivity and Evolutionary Divergence of Metabotropic Glutamate Receptors for Endogenous Ligands and G Proteins Coupled to Phospholipase C or TRP Channels*

    Science.gov (United States)

    Kang, Hye Jin; Menlove, Kit; Ma, Jianpeng; Wilkins, Angela; Lichtarge, Olivier; Wensel, Theodore G.

    2014-01-01

    To define the upstream and downstream signaling specificities of metabotropic glutamate receptors (mGluR), we have examined the ability of representative mGluR of group I, II, and III to be activated by endogenous amino acids and catalyze activation of G proteins coupled to phospholipase C (PLC), or activation of Gi/o proteins coupled to the ion channel TRPC4β. Fluorescence-based assays have allowed us to observe interactions not previously reported or clearly identified. We have found that the specificity for endogenous amino acids is remarkably stringent. Even at millimolar levels, structurally similar compounds do not elicit significant activation. As reported previously, the clear exception is l-serine-O-phosphate (l-SOP), which strongly activates group III mGluR, especially mGluR4,-6,-8 but not group I or II mGluR. Whereas l-SOP cannot activate mGluR1 or mGluR2, it acts as a weak antagonist for mGluR1 and a potent antagonist for mGluR2, suggesting that co-recognition of l-glutamate and l-SOP arose early in evolution, and was followed later by divergence of group I and group II mGluR versus group III in l-SOP responses. mGluR7 has low affinity and efficacy for activation by both l-glutamate and l-SOP. Molecular docking studies suggested that residue 74 corresponding to lysine in mGluR4 and asparagine in mGluR7 might play a key role, and, indeed, mutagenesis experiments demonstrated that mutating this residue to lysine in mGluR7 enhances the potency of l-SOP. Experiments with pertussis toxin and dominant-negative Gαi/o proteins revealed that mGluR1 couples strongly to TRPC4β through Gαi/o, in addition to coupling to PLC through Gαq/11. PMID:25193666

  4. The adoption of ‘International Accounting Standard (IAS) 12 Income Taxes’: Convergence or divergence with local accounting standards in selected ASEAN countries?

    OpenAIRE

    Prem W.S. Yapa; Diane Kraal; Mahesh Joshi

    2015-01-01

    This article concerns inter-disciplinary research on questions about the socio-economic impact of the adoption and convergence of International Financial Reporting Standards (IFRS) with local standards in selected countries. The article approaches the research in two stages. The first stage concerns the findings and analysis relating to the general impact of the IFRS standards on Singapore and Malaysia. Findings reveal that respondents expressed reservations about cited IFRS adoption benefits...

  5. Phosphorus and phytase levels for layer hens

    Directory of Open Access Journals (Sweden)

    Juliana Cristina Ramos Rezende

    2013-02-01

    Full Text Available The objective of this research was to evaluate the performance and bone quality of laying hens after peak production fed diets containing phosphorus levels and phytase. An experiment was conducted with 384 Hy-line distributed in a completely randomized in a factorial 4 x 3 with 4 levels of available phosphorus and 3 levels of phytase. The experimental period was divided into four periods of 28 days, at the end of each cycle were determined experimental feed intake, egg production, egg weight, feed conversion, mortality, and average egg weight, shell thickness, Haugh units and specific gravity. At the end of the experimental period were determined amounts of calcium and phosphorus excreted by the method of total excreta collection and a fowl per experimental unit was sacrificed for collection of bones and evaluation of width, length and level of robustness from femur and tibia. There was interaction between phosphorus levels and phytase on feed intake, feed conversion and percentage of posture. For inclusion levels of phytase all egg quality variables showed no significant differences. The treatments did not affect bone characteristics of laying hens.

  6. Shrimp cephalothorax meal in laying hen diets

    International Nuclear Information System (INIS)

    Salas-Duran, Catalina; Chacon-Villalobos, Alejandro; Zamora-Sanchez, Laura

    2015-01-01

    The effect of shrimp meal (SM) was measure in commercial laying hen diets. Pleuroncodes planipes was used in Costa Rica, from April to September 2013, to obtain a meal (SM) with a yield of 15%, particle size of 256 μg and negative for Salmonella sp. Proximate analysis was performed to the SM: crude protein (40,67%), ether extract (11,05%), crude fiber (7,12%), ash (27,48%), calcium (9,03%), phosphorus (2,66%), amino acid profile, pepsin digestibility (84%) and acidity (8,34). Subsequently, a trial was performed with 140 40-week-old Hy-Line Brown laying hens, fed with four different diets containing increasing levels of inclusion of SM (0%, 5%, 10%, and 15%) during four weeks; and formulated according to the ideal protein and digestible amino acids concepts; being isocaloric and isoproteic. The variables experimentally evaluated were: production percentage, feed intake, body weight, mortality, egg weight and feed conversion ratio. Only egg weight changed significantly between treatments in the third week (p [es

  7. 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

  8. Converging or Diverging Lens?

    Science.gov (United States)

    Branca, Mario

    2013-01-01

    Why does a lens magnify? Why does it shrink objects? Why does this happen? The activities that we propose here are useful in helping us to understand how lenses work, and they show that the same lens can have different magnification capabilities. A converging lens can also act as a diverging lens. (Contains 4 figures.)

  9. Local divergence and curvature divergence in first order optics

    Science.gov (United States)

    Mafusire, Cosmas; Krüger, Tjaart P. J.

    2018-06-01

    The far-field divergence of a light beam propagating through a first order optical system is presented as a square root of the sum of the squares of the local divergence and the curvature divergence. The local divergence is defined as the ratio of the beam parameter product to the beam width whilst the curvature divergence is a ratio of the space-angular moment also to the beam width. It is established that the beam’s focusing parameter can be defined as a ratio of the local divergence to the curvature divergence. The relationships between the two divergences and other second moment-based beam parameters are presented. Their various mathematical properties are presented such as their evolution through first order systems. The efficacy of the model in the analysis of high power continuous wave laser-based welding systems is briefly discussed.

  10. The adoption of ‘International Accounting Standard (IAS 12 Income Taxes’: Convergence or divergence with local accounting standards in selected ASEAN countries?

    Directory of Open Access Journals (Sweden)

    Prem W.S. Yapa

    2015-09-01

    Full Text Available This article concerns inter-disciplinary research on questions about the socio-economic impact of the adoption and convergence of International Financial Reporting Standards (IFRS with local standards in selected countries. The article approaches the research in two stages. The first stage concerns the findings and analysis relating to the general impact of the IFRS standards on Singapore and Malaysia. Findings reveal that respondents expressed reservations about cited IFRS adoption benefits, including increases of foreign investment and equity cost reductions; and stakeholder confidence has been eroded by the complex harmonising of principles-based ‘fair value’ requirements. Debate continues on the application of IFRS regarding standards on financial instruments, real estate and agriculture. Our qualitative research methodology of survey uses institutional theory and stakeholder theory for analysis. The second stage posits further research for IAS12 Income Taxes, given accounting standards are one starting point for tax compliance, and that income taxes form part of financial statements. A test questionnaire was prepared and industry respondents were asked questions on the extent of IAS12’s challenges to practitioners in Australia.

  11. The response of broiler breeder hens to dietary balanced protein

    African Journals Online (AJOL)

    Research

    2016-08-26

    Aug 26, 2016 ... between the two feeding strategies or dietary protein levels, nor were ... supplied, whilst in other cases hens may not consume their daily allocation, ..... Aviagen, 2014. http://en.aviagen.com/assets/Tech_Center/Ross_Broiler/ ...

  12. 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

  13. Performance comparison of dwarf laying hens segregating for the naked neck gene in temperate and subtropical environments

    Directory of Open Access Journals (Sweden)

    Bordas André

    2009-01-01

    Full Text Available Abstract This study compares laying performances between two environments of dwarf laying hen lines segregating for the naked neck mutation (NA locus, a selected dwarf line of brown-egg layers and its control line. Layers with one of the three genotypes at the NA locus were produced from 11 sires from the control line and 12 sires from the selected line. Two hatches produced 216 adult hens in Taiwan and 297 hens in France. Genetic parameters for laying traits were estimated in each environment and the ranking of sire breeding values was compared between environments. Laying performance was lower, and mortality was higher in Taiwan than in France. The line by environment interaction was highly significant for body weight at 16 weeks, clutch length and egg number, with or without Box-Cox transformation. The selected line was more sensitive to environmental change but in Taiwan it could maintain a higher egg number than the control line. Estimated heritability values in the selected line were higher in France than in Taiwan, but not for all the traits in the control line. The rank correlations between sire breeding values were low within the selected line and slightly higher in the control line. A few sire families showed a good ranking in both environments, suggesting that some families may adapt better to environmental change.

  14. Universal portfolios generated by the Bregman divergence

    Science.gov (United States)

    Tan, Choon Peng; Kuang, Kee Seng

    2017-04-01

    The Bregman divergence of two probability vectors is a stronger form of the f-divergence introduced by Csiszar. Two versions of the Bregman universal portfolio are presented by exploiting the mean-value theorem. The explicit form of the Bregman universal portfolio generated by a function of a convex polynomial is derived and studied empirically. This portfolio can be regarded as another generalized of the well-known Helmbold portfolio. By running the portfolios on selected stock-price data sets from the local stock exchange, it is shown that it is possible to increase the wealth of the investor by using the portfolios in investment.

  15. Convergence from divergence

    Science.gov (United States)

    Costin, Ovidiu; Dunne, Gerald V.

    2018-01-01

    We show how to convert divergent series, which typically occur in many applications in physics, into rapidly convergent inverse factorial series. This can be interpreted physically as a novel resummation of perturbative series. Being convergent, these new series allow rigorous extrapolation from an asymptotic region with a large parameter, to the opposite region where the parameter is small. We illustrate the method with various physical examples, and discuss how these convergent series relate to standard methods such as Borel summation, and also how they incorporate the physical Stokes phenomenon. We comment on the relation of these results to Dyson’s physical argument for the divergence of perturbation theory. This approach also leads naturally to a wide class of relations between bosonic and fermionic partition functions, and Klein-Gordon and Dirac determinants.

  16. 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)

  17. Mallard Use of Hen HousesTM in Eastern Ontario

    Directory of Open Access Journals (Sweden)

    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.

  18. Testing evolutionary hypotheses for phenotypic divergence using landscape genetics.

    Science.gov (United States)

    Funk, W Chris; Murphy, Melanie A

    2010-02-01

    Understanding the evolutionary causes of phenotypic variation among populations has long been a central theme in evolutionary biology. Several factors can influence phenotypic divergence, including geographic isolation, genetic drift, divergent natural or sexual selection, and phenotypic plasticity. But the relative importance of these factors in generating phenotypic divergence in nature is still a tantalizing and unresolved problem in evolutionary biology. The origin and maintenance of phenotypic divergence is also at the root of many ongoing debates in evolutionary biology, such as the extent to which gene flow constrains adaptive divergence (Garant et al. 2007) and the relative importance of genetic drift, natural selection, and sexual selection in initiating reproductive isolation and speciation (Coyne & Orr 2004). In this issue, Wang & Summers (2010) test the causes of one of the most fantastic examples of phenotypic divergence in nature: colour pattern divergence among populations of the strawberry poison frog (Dendrobates pumilio) in Panama and Costa Rica (Fig. 1). This study provides a beautiful example of the use of the emerging field of landscape genetics to differentiate among hypotheses for phenotypic divergence. Using landscape genetic analyses, Wang & Summers were able to reject the hypotheses that colour pattern divergence is due to isolation-by-distance (IBD) or landscape resistance. Instead, the hypothesis left standing is that colour divergence is due to divergent selection, in turn driving reproductive isolation among populations with different colour morphs. More generally, this study provides a wonderful example of how the emerging field of landscape genetics, which has primarily been applied to questions in conservation and ecology, now plays an essential role in evolutionary research.

  19. Regularization of divergent integrals

    OpenAIRE

    Felder, Giovanni; Kazhdan, David

    2016-01-01

    We study the Hadamard finite part of divergent integrals of differential forms with singularities on submanifolds. We give formulae for the dependence of the finite part on the choice of regularization and express them in terms of a suitable local residue map. The cases where the submanifold is a complex hypersurface in a complex manifold and where it is a boundary component of a manifold with boundary, arising in string perturbation theory, are treated in more detail.

  20. Effects of organic and inorganic dietary selenium supplementation on gene expression profiles in oviduct tissue from broiler-breeder hens.

    Science.gov (United States)

    Brennan, K M; Crowdus, C A; Cantor, A H; Pescatore, A J; Barger, J L; Horgan, K; Xiao, R; Power, R F; Dawson, K A

    2011-05-01

    Selenium (Se) is an essential component of at least 25 selenoproteins involved in a multitude of physiological functions, including reproduction. However, relatively little is known about the mechanisms by which Se exerts its physiological effects in reproductive tissue. The objective of this study was to compare the effect of long-term inorganic Se (sodium selenite, SS) and organic yeast-derived Se (Sel-Plex(®), SP) supplementations on tissue Se content and gene expression patterns in the oviduct of broiler-breeder hens. Hens were randomly assigned at 6 weeks of age to one of the three treatments: basal semi-purified diet (control), basal diet+0.3 ppm Se as SP or basal diet+0.3 ppm Se as SS. At 49 weeks, oviduct tissue from hens randomly selected from each treatment (n=7) was analyzed for Se content and gene expression profiles using the Affymetrix Chicken genome array. Gene expression data were evaluated using GeneSpring GX 10.0 (Silicon Genetics, Redwood, CA) and Ingenuity Pathways Analysis software (Ingenuity Systems, Redwood City, CA). Oviduct Se concentration was greater with Se supplementation compared with the control (P≤0.05) but did not differ between SS- and SP-supplemented groups. Gene expression analysis revealed that the quantity of gene transcripts associated with energy production and protein translation were greater in the oviduct with SP but not SS supplementation. Targets up-regulated by SP, but not SS, included genes encoding several subunits of the mitochondrial respiratory complexes, ubiquinone production and ribosomal subunits. SS hens showed a decrease in transcripts of genes involved in respiratory complexes, ATP synthesis and protein translation and metabolism in oviduct relative to control hens. In this study, although tissue Se concentrations did not differ between hens fed SS- and SP-supplemented diets, expression patterns of genes involved in energy production and protein synthesis pathways differed between treatments. These

  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. 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.

  4. Selección masal divergente por prolificidad en maíz y sus efectos en las características de la espiga Divergence mass selection for prolificacy in maize and their effects over the tassel characteristics

    Directory of Open Access Journals (Sweden)

    Martínez. Orlando

    1992-06-01

    Full Text Available Uno de los caracteres más importantes en maíz, es la prolificidad, medida como el número de mazorcas por planta, puesto que es uno de los principales componentes del rendimiento. Se espera que a mayor prolificidad corresponda mayor productividad. Este estudio se realizó con el propósito
    de evaluar la respuesta directa debida a la selección masal divergente por número de mazorcas por planta en maíz y su efecto indirecto sobre las características de la espiga. La población original correspondió a la variedad sintética de maíz, Harinoso Mosquera I. Sin.2, y sus últimos 9 de 22
    ciclos de seleción masal divergente. La presente investigación se desarrollo en el CI.Tibaitatá, ubicado en el municipio de
    Mosquera, a 2543 m.s.n.m., una temperatura promedia de 14° C y precipitación promedio anual de 750 mm. La selección resultó de un incremento de 1.06 a 1.70
    mazorcas por planta (2,32% por ciclo cuando la selección fue en favor de la prolificidad y una reducción de 1.06 a 0.92 mazorcas por planta (-4,46% por ciclo cuando fue
    contraria. El rendimiento estuvo positiva y altamente correlacionado (r=0,87** con prolificidad. El efecto colateral de la selección divergente, no se manifestó en la
    longitud de la espiguilla (centro y ramificaciones
    y el índice de condensación. Se plantea la utilidad de estas características para la clasificación de las razas de maíz.The number of ears per plant or prolificacy is one of the most important traits in maize, since it is one of the mayor yield
    components. It is expect that to a higher number of earsper plantit would correspond a higher yield. This study was conducted with the purpose of evaluating both the
    direct response due to divergence mass selection per prolificacy ande the correlated response overthe male inflorescence. The base population was the synthetic Harinoso
    Mosquera I Sin. 2, and the last 9 of 22 cycles of divergence mass

  5. Characterization of Egg Laying Hen and Broiler Fecal Microbiota in Poultry Farms in Croatia, Czech Republic, Hungary and Slovenia

    OpenAIRE

    Videnska, Petra; Rahman, Md. Masudur; Faldynova, Marcela; Babak, Vladimir; Matulova, Marta Elsheimer; Prukner-Radovcic, Estella; Krizek, Ivan; Smole-Mozina, Sonja; Kovac, Jasna; Szmolka, Ama; Nagy, Bela; Sedlar, Karel; Cejkova, Darina; Rychlik, Ivan

    2014-01-01

    Poultry meat is the most common protein source of animal origin for humans. However, intensive breeding of animals in confined spaces has led to poultry colonisation by microbiota with a zoonotic potential or encoding antibiotic resistances. In this study we were therefore interested in the prevalence of selected antibiotic resistance genes and microbiota composition in feces of egg laying hens and broilers originating from 4 different Central European countries determined by real-time PCR an...

  6. Low genetic diversity and local adaptive divergence of Dracaena cambodiana (Liliaceae) populations associated with historical population bottlenecks and natural selection: an endangered long-lived tree endemic to Hainan Island, China.

    Science.gov (United States)

    Zheng, D-J; Xie, L-S; Zhu, J-H; Zhang, Z-L

    2012-09-01

    Historical population bottlenecks and natural selection have important effects on the current genetic diversity and structure of long-lived trees. Dracaena cambodiana is an endangered, long-lived tree endemic to Hainan Island, China. Our field investigations showed that only 10 populations remain on Hainan Island and that almost all have been seriously isolated and grow in distinct habitats. A considerable amount of genetic variation at the species level, but little variation at the population level, and a high level of genetic differentiation among the populations with limited gene flow in D. cambodiana were detected using inter-simple sequence repeat (ISSR) and random amplified polymorphic DNA (RAPD) analyses. No significant correlation was found between genetic diversity and actual population size, as the genetic diversities were similar regardless of population size. The Mantel test revealed that there was no correlation between genetic and geographic distances among the 10 populations. The UPGMA, PCoA and Bayesian analyses showed that local adaptive divergence has occurred among the D. cambodiana populations, which was further supported by habitat-private fragments. We suggest that the current genetic diversity and population differentiation of D. cambodiana resulted from historical population bottlenecks and natural selection followed by historical isolation. However, the lack of natural regeneration of D. cambodiana indicates that former local adaptations with low genetic diversity may have been genetically weak and are unable to adapt to the current ecological environments. © 2012 German Botanical Society and The Royal Botanical Society of the Netherlands.

  7. 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

  8. Short communication Divergent selection for reproduction affects ...

    African Journals Online (AJOL)

    1 Institute for Animal Production: Elsenburg, Private Bag X1, Elsenburg 7607, South Africa ... strike prevention method is now considered unethical and it is accepted that it ... The resource flock was maintained at Elsenburg Research Farm.

  9. 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.

  10. Hen på bibliotek : En diskursanalys av genusintresserade bibliotekariers tal om begreppet hen

    OpenAIRE

    Almström, Vera Henrika

    2013-01-01

    This master’s thesis looks at discourses that use the pronoun ”hen”. The media debate in Sweden over this pronoun in 2012 started in connection with the publishing of a children’s picture book: Kivi och monsterhund, by Jesper Lundqvist and Bettina Jansson. The essay investigates how eight librarians, who take an interest in and work with gender issues, talk about the pronoun hen and about this picture book and other books that have characters which are not named as a sex/gender. The essay tak...

  11. Behavioural divergence, interfertility and speciation: a review.

    Science.gov (United States)

    Pillay, Neville; Rymer, Tasmin L

    2012-11-01

    Behavioural compatibility between mates is fundamental for maintaining species boundaries and is achieved through appropriate communication between males and females. A breakdown in communication will lead to behavioural divergence and reduced interfertility. In this review, we summarise the current knowledge on male signals and female perception of these signals, integrating the literature from several taxa. We advocate that signaller-perceiver coevolution, which is usually under strong stabilising selection to enable mating, forms the basis of species-specific mate recognition systems. The mechanisms (phylogeny, geography, ecology, biology) shaping signaller-perceiver systems are briefly discussed to demonstrate the factors underpinning the evolution of signaller-perceiver couplings. Since divergence and diversification of communication systems is driven by changes in the mechanical properties of sensory pathways and morphology of sensory organs, we highlight signal modalities (auditory, olfactory, visual, tactile) and their importance in communication, particularly in mate selection. Next, using available examples and generating a stylised model, we suggest how disruption (biological, ecological, stochastic) of signaller-perceiver systems drives behavioural divergence and consequently results in reduced interfertility and speciation. Future studies should adopt an integrative approach, combining multiple parameters (phylogeny, adaptive utility of communication systems, genetics and biomechanical/biochemical properties of signals and perception) to explore how disruption of signaller-perceiver systems results in behavioural divergence and reduced interfertility. Finally, we question the impact that rapid environmental change will have on disruption of communication systems, potentially interfering with signaller-perceiver couplings. Copyright © 2012 Elsevier B.V. All rights reserved.

  12. Evaluation of Two Compressed Air Foam Systems for Culling Caged Layer Hens

    Science.gov (United States)

    Weiher, Jaclyn A.; Alphin, Robert L.; Hougentogler, Daniel P.

    2018-01-01

    Simple Summary Control of avian influenza and similar diseases in commercial poultry operations is challenging; the six major steps are surveillance, biosecurity, quarantine, depopulation, disposal, and cleaning and disinfection. Depopulation is used to cull animals that are terminally ill and to reduce the number of animals that can spread an untreatable disease. Water-based foam depopulation was used effectively during the 2014–2015 highly pathogenic avian influenza outbreak in the United States. Water-based foam, however, cannot be used effectively in caged poultry operations. Compressed air foam systems were initially developed for structural fire-fighting and, with modifications, can provide the conditions required to effectively penetrate a poultry cage and provide sufficient residence time for depopulation. In this experiment, compressed air foam was used to depopulate caged layer hens. Compressed air foam resulted in faster unconsciousness than carbon dioxide gassing. The experiment demonstrated that compressed air foam systems have promise for depopulating birds raised in cages. Abstract Outbreaks of avian influenza (AI) and other highly contagious poultry diseases continue to be a concern for those involved in the poultry industry. In the situation of an outbreak, emergency depopulation of the birds involved is necessary. In this project, two compressed air foam systems (CAFS) were evaluated for mass emergency depopulation of layer hens in a manure belt equipped cage system. In both experiments, a randomized block design was used with multiple commercial layer hens treated with one of three randomly selected depopulation methods: CAFS, CAFS with CO2 gas, and CO2 gas. In Experiment 1, a Rowe manufactured CAFS was used, a selection of birds were instrumented, and the time to unconsciousness, brain death, altered terminal cardiac activity and motion cessation were recorded. CAFS with and without CO2 was faster to unconsciousness, however, the other

  13. Divergent Perturbation Series

    International Nuclear Information System (INIS)

    Suslov, I.M.

    2005-01-01

    Various perturbation series are factorially divergent. The behavior of their high-order terms can be determined by Lipatov's method, which involves the use of instanton configurations of appropriate functional integrals. When the Lipatov asymptotic form is known and several lowest order terms of the perturbation series are found by direct calculation of diagrams, one can gain insight into the behavior of the remaining terms of the series, which can be resummed to solve various strong-coupling problems in a certain approximation. This approach is demonstrated by determining the Gell-Mann-Low functions in φ 4 theory, QED, and QCD with arbitrary coupling constants. An overview of the mathematical theory of divergent series is presented, and interpretation of perturbation series is discussed. Explicit derivations of the Lipatov asymptotic form are presented for some basic problems in theoretical physics. A solution is proposed to the problem of renormalon contributions, which hampered progress in this field in the late 1970s. Practical perturbation-series summation schemes are described both for a coupling constant of order unity and in the strong-coupling limit. An interpretation of the Borel integral is given for 'non-Borel-summable' series. Higher order corrections to the Lipatov asymptotic form are discussed

  14. 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...

  15. 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...

  16. Transcriptome-wide patterns of divergence during allopatric evolution.

    Science.gov (United States)

    Pereira, Ricardo J; Barreto, Felipe S; Pierce, N Tessa; Carneiro, Miguel; Burton, Ronald S

    2016-04-01

    Recent studies have revealed repeated patterns of genomic divergence associated with species formation. Such patterns suggest that natural selection tends to target a set of available genes, but is also indicative that closely related taxa share evolutionary constraints that limit genetic variability. Studying patterns of genomic divergence among populations within the same species may shed light on the underlying evolutionary processes. Here, we examine transcriptome-wide divergence and polymorphism in the marine copepod Tigriopus californicus, a species where allopatric evolution has led to replicate sets of populations with varying degrees of divergence and hybrid incompatibility. Our analyses suggest that relatively small effective population sizes have resulted in an exponential decline of shared polymorphisms during population divergence and also facilitated the fixation of slightly deleterious mutations within allopatric populations. Five interpopulation comparisons at three different stages of divergence show that nonsynonymous mutations tend to accumulate in a specific set of proteins. These include proteins with central roles in cellular metabolism, such as those encoded in mtDNA, but also include an additional set of proteins that repeatedly show signatures of positive selection during allopatric divergence. Although our results are consistent with a contribution of nonadaptive processes, such as genetic drift and gene expression levels, generating repeatable patterns of genomic divergence in closely related taxa, they also indicate that adaptive evolution targeting a specific set of genes contributes to this pattern. Our results yield insights into the predictability of evolution at the gene level. © 2016 John Wiley & Sons Ltd.

  17. Investigation on the effects of dietary protein reduction with constant ratio of digestible sulfur amino acids and threonine to lysine on performance, egg quality and protein retention in two strains of laying hens

    Directory of Open Access Journals (Sweden)

    Farhad Foroudi

    2013-01-01

    Full Text Available An experiment was conducted to determine the possibility of using various levels of crude protein (CP by providing laying hens with constant levels of digestible sulfur amino acid, threonine and lysine to improve performance and egg quality. The experiment was conducted as a completely randomized block design in a factorial arrangement (4 × 2 with 8 replicates of 10 hens in each. Factors included 4 levels of CP (18.5%, 17.5%, 16.5% and 15.5% and 2 strains (LSL and Hy-Line W-36 of laying hens. Hens were fed experimental diets from 25 to 33 weeks of age. Production performance was measured for eight weeks and egg quality characteristics were determined at 29 and 33 weeks of age. Protein reduction decreased egg weight, egg mass and hen body weight linearly (P≤0.01. Egg production was not affected by protein reduction but feed efficiency, and average daily feed intake increased significantly (P≤0.01. Lohmann Selected Leghorn laying hens showed significantly higher egg production, egg weight, egg mass, weight gain, feed efficiency and feed intake compared to the W-36 laying hens (P≤0.01. Shell thickness increased linearly as protein levels decreased (P≤0.05. There were significant differences between two strains on the egg quality characteristics (P≤0.01. Significant (P≤0.05 CP × strain interactions were observed for hen weight, albumen height, Haugh units, yolk and shell percentage. Based on the results of this experiment, a reduction in dietary protein level (from 18.5% to 15.5%, without any alteration in digestible TSAA and Thr: Lys ratio, led to inferior egg mass and feed conversion ratio during the peak production period.

  18. Riverscape genetics identifies replicated ecological divergence across an Amazonian ecotone.

    Science.gov (United States)

    Cooke, Georgina M; Landguth, Erin L; Beheregaray, Luciano B

    2014-07-01

    Ecological speciation involves the evolution of reproductive isolation and niche divergence in the absence of a physical barrier to gene flow. The process is one of the most controversial topics of the speciation debate, particularly in tropical regions. Here, we investigate ecologically based divergence across an Amazonian ecotone in the electric fish, Steatogenys elegans. We combine phylogenetics, genome scans, and population genetics with a recently developed individual-based evolutionary landscape genetics approach that incorporates selection. This framework is used to assess the relative contributions of geography and divergent natural selection between environments as biodiversity drivers. We report on two closely related and sympatric lineages that exemplify how divergent selection across a major Amazonian aquatic ecotone (i.e., between rivers with markedly different hydrochemical properties) may result in replicated ecologically mediated speciation. The results link selection across an ecological gradient with reproductive isolation and we propose that assortative mating based on water color may be driving the divergence. Divergence resulting from ecologically driven selection highlights the importance of considering environmental heterogeneity in studies of speciation in tropical regions. Furthermore, we show that framing ecological speciation in a spatially explicit evolutionary landscape genetics framework provides an important first step in exploring a wide range of the potential effects of spatial dependence in natural selection. © 2014 The Author(s). Evolution © 2014 The Society for the Study of Evolution.

  19. Active learning for noisy oracle via density power divergence.

    Science.gov (United States)

    Sogawa, Yasuhiro; Ueno, Tsuyoshi; Kawahara, Yoshinobu; Washio, Takashi

    2013-10-01

    The accuracy of active learning is critically influenced by the existence of noisy labels given by a noisy oracle. In this paper, we propose a novel pool-based active learning framework through robust measures based on density power divergence. By minimizing density power divergence, such as β-divergence and γ-divergence, one can estimate the model accurately even under the existence of noisy labels within data. Accordingly, we develop query selecting measures for pool-based active learning using these divergences. In addition, we propose an evaluation scheme for these measures based on asymptotic statistical analyses, which enables us to perform active learning by evaluating an estimation error directly. Experiments with benchmark datasets and real-world image datasets show that our active learning scheme performs better than several baseline methods. Copyright © 2013 Elsevier Ltd. All rights reserved.

  20. 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.

  1. Design of a divergence and alignment indicator

    International Nuclear Information System (INIS)

    Brenizer, J.S. Jr.; Raine, D.A.; Gao, J.; Chen, J.

    1996-01-01

    The divergence and alignment indicator (DAI) is an extension of the ASTM E803 L/D thermal neutron radiography L/D device that allows the user to determine both the beam centerline and the beam divergence. The DAI was made using aluminium plate and rods, and incorporated cadmium wire for contrast. Circular symmetry was utilized to simplify manufacture. The DAI was placed with the five posts against the film cassette or radioscopic imaging device in the physical center of the beam. The DAI was perpendicular to the selected beam radius when the front and back center Cd wire images overlap. The degree of misalignment was indicated by their image positions. After the DAI was aligned, analysis of the cadmium wire ''+'' image spacing yielded the beam divergence. The DAI was tested in a neutron beam which has an L/D of 30 but a small degree of divergence. The DAI was also imaged using an X-ray source. The point source predictions of Cd wire image locations showed good agreement with those measured from the X-ray radiograph. The neutron radiographic locations could be predicted using the point source equations, even though the neutron beam was a complex distributed source. (orig.)

  2. 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...

  3. Quadratic divergences and dimensional regularisation

    International Nuclear Information System (INIS)

    Jack, I.; Jones, D.R.T.

    1990-01-01

    We present a detailed analysis of quadratic and quartic divergences in dimensionally regulated renormalisable theories. We perform explicit three-loop calculations for a general theory of scalars and fermions. We find that the higher-order quartic divergences are related to the lower-order ones by the renormalisation group β-functions. (orig.)

  4. 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.

  5. 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.

  6. Safety evaluation of phytosterols in laying hens: effects on laying performance, clinical blood parameters, and organ development.

    Science.gov (United States)

    Shi, S R; Shen, Y R; Chang, L L; Zhou, C J; Bo, Z; Wang, Z Y; Tong, H B; Zou, J M

    2014-03-01

    Phytosterols are intended for use as a novel food ingredient with plasma cholesterol-lowering activity. Although phytosterols are naturally present in the normal diet, daily consumption is insufficient to ensure plasma cholesterol-lowering levels. Therefore, phytosterols may be added to the diets to achieve the desired cholesterol-lowering activity. A subchronic laying hen safety study was conducted to examine if high-dose phytosterols could affect the safety of hens. Three hundred sixty 21-wk-old Hy-Line Brown laying hens were randomly assigned to 5 groups with 6 replicates of 12 birds each; after 3 wk, birds were fed diets supplemented with 0, 20, 80, 400, and 800 mg/kg of phytosterols for 12 wk. Throughout the study, clinical observations and laying performance were measured. At the end of the study, birds were subjected to a full postmortem examination: blood samples were taken for clinical pathology, selected organs were weighed, and specified tissues were taken for subsequent histological examination. No treatment-related changes that were considered to be of toxicological significance were observed. Therefore, a nominal phytosterol concentration of 800 mg/kg was considered to be the no-observed-adverse-effect level.

  7. 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.

  8. Haematology and serum biochemistry of laying hens fed red pepper ...

    African Journals Online (AJOL)

    The hematology and serum biochemistry of ISA brown laying hens fed red pepper (Capsicum annum. L.) as feed additive in their diet was studied. Sixty (60) laying birds (in their 32nd week) were randomly allotted to four different dietary treatments with graded levels of red pepper (Capsicum annum. L.) as additive.

  9. Enrichment of bifidobacteria in the hen caeca by dietary inulin

    Czech Academy of Sciences Publication Activity Database

    Marounek, Milan; Rada, V.; Dušková, D.; Petr, J.

    2001-01-01

    Roč. 46, č. 1 (2001), s. 73-75 ISSN 0015-5632 R&D Projects: GA ČR GA524/99/0480; GA AV ČR KSK5020115 Keywords : bifidobacteria * hen * inulin Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 0.776, year: 2001

  10. 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...

  11. Consumers’ Preferences for Shell Eggs Regarding Laying Hen Welfare

    OpenAIRE

    Heng, Yan; Peterson, Hikaru Hanawa; Li, Xianghong

    2012-01-01

    DRAFT, do not cite. Please cite formally published version: Heng, Yan, Hikaru Hanawa Peterson, and Xianghong Li. "Consumer Attitudes toward Farm-Animal Welfare: The Case of Laying Hens." Journal of Agricultural and Resource Economics 38.3 (2013): 418-434. Available at: http://purl.umn.edu/165936

  12. Performance and economy of production of laying hens fed graded ...

    African Journals Online (AJOL)

    Experiments were carried out to evaluate the performance of laying hens fed fermented wild cocoyam corm (FWCC) as a partial replacement for maize. Two hundred and forty (240) Nera black laying birds were randomly allocated to four experimental diets formulated on 0, 10, 20 and 30% FWCC as graded replacement ...

  13. Utilisation of synthetic amino acids by broiler breeder hens | Nonis ...

    African Journals Online (AJOL)

    This study was conducted to examine the response of broiler breeder hens to feeds supplemented with synthetic lysine and methionine when fed once or twice daily during peak production. Replacing intact protein with increasing amounts of free lysine and methionine, up to 2.3 g/kg feed, had no effect on feed intake, ...

  14. The effect of feeding clinoptilolite (zeolite) to laying hens

    African Journals Online (AJOL)

    The effect of feeding clinoptilolite (zeolite) to laying hens. M.D. Olver. Animal and Dairy Science Research Institute, lrene. One hundred and twenty 4-month-old, single-combed, brown. Hy-Line pullets were fed two isocaloric diets containing 16 or. 13,5o/o protein with and without 5% clinoptilolite in four.

  15. One Hen: Teaching Elementary-Level Economics for Civic Engagement

    Science.gov (United States)

    Whitlock, Annie McMahon

    2013-01-01

    This dissertation is a qualitative case study focused on describing and analyzing the student and teacher experience with One Hen, a project-based learning unit specifically designed to teach civic engagement. In this study I address three questions: 1) Do fifth-grade students' knowledge and skills in economics change after participating in a…

  16. 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.

  17. The Case for Bull Dogs and Mother Hens.

    Science.gov (United States)

    Neugebauer, Bonnie; Neugebauer, Roger

    1996-01-01

    Describes traits of effective child care team members: instigator--develops ideas; day-dream believer--suggests solutions; jester--relieves tension; mother hen--ensures fair treatment; nervous Nellie--critiques ideas; keeper of the faith--focuses on center's mission; bull dog--keeps on task; compromiser--preserves unity; and mover and…

  18. Charged Analogues of Henning Knutsen Type Solutions in General Relativity

    Science.gov (United States)

    Gupta, Y. K.; Kumar, Sachin; Pratibha

    2011-11-01

    In the present article, we have found charged analogues of Henning Knutsen's interior solutions which join smoothly to the Reissner-Nordstrom metric at the pressure free interface. The solutions are singularity free and analyzed numerically with respect to pressure, energy-density and charge-density in details. The solutions so obtained also present the generalization of A.L. Mehra's solutions.

  19. 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.

  20. Linear energy divergences in Coulomb gauge QCD

    OpenAIRE

    Andrasi, A.

    2011-01-01

    The structure of linear energy divergences is analysed on the example of one graph to 3-loop order. Such dangerous divergences do cancel when all graphs are added, but next to leading divergences do not cancel out.

  1. 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.

  2. 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.

  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

    2016-06-01

    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.

  4. Boiling flow through diverging microchannel

    Indian Academy of Sciences (India)

    such systems, for small pressure drop penalty and with good flow stability. .... ied the effect of divergence angle on mean and transient pressure/temperature distribution and .... supplying a fixed voltage and current using a power source meter.

  5. Atmospheric horizontal divergence and diffusion

    International Nuclear Information System (INIS)

    Castans, M.

    1981-01-01

    The action of horizontal divergence on diffusion near the ground is established through.a very simple flow model. The shape of the well-known Pasquill-Gifford-Turner curves, that apparently take account in some way of divergence, is justified. The possibility of explaining the discre--pancies between the conventional straight line model and experimental results, mainly under low-wind-speed satable conditions, is considered. Some hints for further research are made. (auth.)

  6. 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

  7. 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

  8. 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.

  9. 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.

  10. Modification of the lipid profile and antioxidant status of the blood plasma of turkey hens fed mixtures with raw or extruded linseed.

    Science.gov (United States)

    Czech, A; Ognik, K; Laszewska, M; Cholewińska, E; Stępniowska, A

    2018-02-01

    The aim of the study was to determine the most beneficial proportion of raw linseed in complete feed mixtures for turkey hens on the basis of lipid and redox indicators in the blood. In experiment 1, the turkey hens received the complete mixture with 2%, 4% or 6% linseed. On the basis of the results obtained in experiment 1, we selected the most effective proportion of linseed, which was given to the birds in the group receiving a 4% linseed additive. In experiment 2, the birds were fed mixtures with a 4% addition of raw or extruded linseed. The use of 4% raw linseed was found to improve production effects (improvement of weight gain, and lower feed conversion ratios), while extruded linseed in the diet of turkey hens did not affect growth performance. The use of linseed (4% and 6%) as a feed component for turkey hens led to an increase in indicators of antioxidant potential, that is the total antioxidant potential of the plasma, vitamins E and C, bilirubin and creatinine. A benefit resulting from the use of linseed, particularly in the amounts of 2% and 4% was a marked improvement in lipid indicators in the blood. The reduced percentage of unsaturated fatty acids (n-3) following the use of extruded linseed resulted in a decrease in lipid peroxidation (lower content of malondialdehyde, superoxide and vitamins C and E in the blood). The most effective dose and form of linseed in the diet of turkey hens is 4% raw linseed. © 2017 Blackwell Verlag GmbH.

  11. 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.

  12. 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.

  13. 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

  14. 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.

  15. Identification of Potential Plasma Biomarkers for Nonalcoholic Fatty Liver Disease by Integrating Transcriptomics and Proteomics in Laying Hens.

    Science.gov (United States)

    Tsai, Meng-Tsz; Chen, Yu-Jen; Chen, Ching-Yi; Tsai, Mong-Hsun; Han, Chia-Li; Chen, Yu-Ju; Mersmann, Harry J; Ding, Shih-Torng

    2017-03-01

    Background: Prevalent worldwide obesity is associated with increased incidence of nonalcoholic fatty liver disease (NAFLD) and metabolic syndrome. The identification of noninvasive biomarkers for NAFLD is of recent interest. Because primary de novo lipogenesis occurs in chicken liver as in human liver, adult chickens with age-associated steatosis resembling human NAFLD is an appealing animal model. Objective: The objective of this study was to screen potential biomarkers in the chicken model for NAFLD by transcriptomic and proteomic analysis. Methods: Hy-Line W-36 laying hens were fed standard feed from 25 to 45 wk of age to induce fatty liver. They were killed every 4 wk, and liver and plasma were collected at each time point to assess fatty liver development and for transcriptomic and proteomic analysis. Next, selected biomarkers were confirmed in additional experiments by providing supplements of the hepatoprotective nutrients betaine [300, 600, or 900 parts per million (ppm) in vivo; 2 mM in vitro] or docosahexaenoic acid (DHA; 1% in vivo; 100 μM in vitro) to 30-wk-old Hy-Line W-36 laying hens for 4 mo and to Hy-Line W-36 chicken primary hepatocytes with oleic acid-induced steatosis. Liver or hepatocyte lipid contents and the expression of biomarkers were then examined. Results: Plasma acetoacetyl-CoA synthetase (AACS), dipeptidyl-peptidase 4 (DPP4), glutamine synthetase (GLUL), and glutathione S -transferase (GST) concentrations are well-established biomarkers for NAFLD. Selected biomarkers had significant positive associations with hepatic lipid deposition ( P steatosis accompanied by the reduced expression of selected biomarkers in vivo and in vitro ( P < 0.05). Conclusion: This study used adult laying hens to identify biomarkers for NAFLD and indicated that AACS, DPP4, GLUL, and GST could be considered to be potential diagnostic indicators for NAFLD in the future. © 2017 American Society for Nutrition.

  16. Health and Welfare in Dutch Organic Laying Hens

    Directory of Open Access Journals (Sweden)

    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

  17. 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

  18. 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

  19. String loop divergences and effective lagrangians

    International Nuclear Information System (INIS)

    Fischler, W.; Klebanov, I.; Susskind, L.

    1988-01-01

    We isolate logarithmic divergences from bosonic string amplitudes on a disc. These divergences are compared with 'tadpole' divergences in the effective field theory, with a covariant cosmological term implied by the counting of string coupling constants. We find an inconsistency between the two. This might be a problem in eliminating divergences from the bosonic string. (orig.)

  20. Adding of ascorbic acid to the culture medium influences the antioxidant status and some biochemical parameters in the hen granulosa cells.

    Science.gov (United States)

    Capcarova, M; Kolesarova, A; Kalafova, A; Bulla, J; Sirotkin, A V

    2015-07-01

    The aim of the present study was to determine the activity of superoxide dismutase (SOD), total antioxidant status (TAS) of the hen granulosa cells, and selected biochemical parameters, including calcium, phosphorus, sodium, potassium, glucose, cholesterol, proteins, in the culture medium of granulosa cells after exposing them to ascorbic acid in vitro conditions. Ovarian granulosa cells of hens were incubated with various doses of ascorbic acid (E1 0.09 mg/ml, E2 0.13 mg/ml, E3 0.17 mg/ml, E4 0.33 mg/ml, E5 0.5 mg/ml). Ascorbic acid did not manifest antioxidant potential and higher doses of ascorbic acid (0.17; 0.33 and 0.5 mg/ml) decreased the activity of SOD in granulosa cells. Vitamin application resulted in a significantly (pascorbic acid might be involved in the regulation of selected biochemical and physiological processes in ovarian granulosa cells.

  1. Semantic search during divergent thinking.

    Science.gov (United States)

    Hass, Richard W

    2017-09-01

    Divergent thinking, as a method of examining creative cognition, has not been adequately analyzed in the context of modern cognitive theories. This article casts divergent thinking responding in the context of theories of memory search. First, it was argued that divergent thinking tasks are similar to semantic fluency tasks, but are more constrained, and less well structured. Next, response time distributions from 54 participants were analyzed for temporal and semantic clustering. Participants responded to two prompts from the alternative uses test: uses for a brick and uses for a bottle, for two minutes each. Participants' cumulative response curves were negatively accelerating, in line with theories of search of associative memory. However, results of analyses of semantic and temporal clustering suggested that clustering is less evident in alternative uses responding compared to semantic fluency tasks. This suggests either that divergent thinking responding does not involve an exhaustive search through a clustered memory trace, but rather that the process is more exploratory, yielding fewer overall responses that tend to drift away from close associates of the divergent thinking prompt. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Fiber level for laying hens during the growing phase

    Directory of Open Access Journals (Sweden)

    Ednardo Rodrigues Freitas

    2014-04-01

    Full Text Available Feeding management of laying hens has been focused on the direct influence of nutrient intake on weight gain, especially at growing phase. This study evaluates nutrient digestibility, performance, development of the digestive tract, body composition, and bone quality of two strains of laying hens fed with different levels of neutral detergent fiber (NDF during the growing phase from the 7th to the 12th week of age. A total of 1,296 birds were distributed in a completely randomized design in a 2 x 3 factorial arrangement (two strains x three levels of NDF with four replicates of 54 birds per treatment. Semi-heavy (Hy Line Brown and light-strain (Lohman LSL pullets were allotted to dietary treatments consisting of 14.50, 16.50, and 18.50% NDF. An interaction between strains and NDF levels was observed only for feed/gain ratio and light-strain pullets had lower performance with 18.50% NDF. The increasing levels of NDF in the diet reduced the coefficients of digestibility of dry matter, nitrogen and gross energy, and the values of metabolizable energy. Higher levels of NDF in the diet increased the relative weight of liver and intestines and reduced gizzard weight. It was also observed differences between bone quality and composition of the femur and tibia of light and semi-heavy hens. The increase in NDF level in ration for growing phase laying hens above 14.50% decreases the nutrient digestibility and the metabolizable energy of the diet; however, it does not affect the carcass composition, bone quality, feed intake, and weight gain, although it may impair feed conversion of light-strain pullets.

  3. Response analysis of the dynamic excitation of hen eggs

    OpenAIRE

    Libor Severa

    2007-01-01

    Commercially produced hen eggs have been tested by means of dynamic excitation of the egg-shells with following analysis of their response. The falling steel ball have been chosen as a exciting instrument and the laser vibrometer have been used as a measuring device for the egg response. The reproductibility of the experiments has been relatively high and the surface velocity has been found to be significantly dependent on the position around the meridian. Analysed frequency spectrum has show...

  4. dd →3 Hen Reaction at Intermediate Energies

    International Nuclear Information System (INIS)

    Ladygina, N. B.

    2012-01-01

    The dd → 3 Hen reaction is considered at the energies between 200 and 520 MeV. The Alt-Grassberger-Sandhas equations are iterated up to the lowest order terms over the nucleon-nucleon t-matrix. The parameterized 3He wave function including five components is used. The angular dependence of the differential cross section and energy dependence of tensor analyzing power T 20 at the zero scattering angle are presented in comparison with the experimental data. (author)

  5. Divergent picornavirus IRES elements

    DEFF Research Database (Denmark)

    Belsham, Graham

    2009-01-01

    Internal ribosome entry site (IRES) elements were first identified about 20 years ago within the 5' untranslated region of picornavirus RNAs. They direct a cap-independent mechanism of translation initiation on the viral RNA. Within the picornavirus family it is now known that there are four...... classes of IRES element which vary in size (450-270nt), they also have different, complex, secondary structures and distinct requirements for cellular proteins to allow them to function. This review describes the features of each class of picornavirus IRES element but focuses on the characteristics...... of the most recently described group, initially identified within the porcine teschovirus-1 RNA, which has strong similarities to the IRES elements from within the genomes of hepatitis C virus and the pestiviruses which are members of the flavivirus family. The selection of the initiation codon...

  6. CASHEW NUT MEAL IN THE FEEDING OF BROWN LAYING HENS

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Braga Cruz

    2015-02-01

    Full Text Available The use of alternative foods to replace conventional foods is becoming a source of research for many researchers. The cashew nut meal (CNM has high energy and protein value, may be a partial substitute for corn and soybean meal for poultry feed. In this context, this research was conducted to evaluate the effect of inclusion of CNM on the utilization of nutrients in the ration for laying hens, as well as the performance and characteristics of the eggs. The study used 180 Dekalb Brown laying hens 27 weeks of age, distributed in a completely randomized design with six treatments and five replicates of six birds. Treatments consisted of a control diet without CNM and others with the inclusion of this food at levels of 5, 10, 15, 20 and 25%. Upon regression analysis, a linear increase in nitrogen metabolism, crude energy and apparently metabolizable energy was seen. The dry matter digestibility and metabolizable energy corrected for rations were not affected by the inclusion of the CNM. Feed intake and egg weight were not affected by the inclusion of the CNM; however, egg production, egg mass, feed conversion, and yolk color worsened linearly with inclusion of CNM. Compared to control diet, the inclusion of CNM worsened the egg mass and feed conversion from 15%, and yolk color from 20%. As a result, it is recommended the inclusion of the CNM in the diet of laying hens at a maximum level of 10%.

  7. 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.

  8. ISOLATION AND PURIFICATION OF LYSOZYME FROM THE HEN EGG WHITE

    Directory of Open Access Journals (Sweden)

    S. S.

    2015-12-01

    Full Text Available The aim of the research was the development of the method of lysozyme isolation from hen egg proteins. Lysozyme was isolated by differential heat denaturation of proteins with changing of the medium pH value, followed by neutralization, dialysis and additional purification by gel chromatography on Sephadex G-50. Activity was determined by bacteriolytic method (with Micrococcus lysodeikticus 4698 as a substrate. The enzyme purity and molecular mass were determined using SDS-electrophoresis and massspectrometry. The method of lysozyme isolation from hen egg proteins with the enzyme yield of 3.2 ± 0.2% and bacteriolytic activity of 22 025 ± 1 500 U/mg is modified. According to electrophoresis data, the isolated enzyme is characterized by high degree of purity (~95–98% and is comparable with lysozyme of AppliChem company by main physical and chemical characteristics. The obtaining product is stored in a crystalline form at low temperature (–24 оC for 9 months. The proposed method allows obtaining active and stable lysozyme with high purity from hen egg protein in laboratory conditions for the usage in biotechnology.

  9. Hyperreal Numbers for Infinite Divergent Series

    OpenAIRE

    Bartlett, Jonathan

    2018-01-01

    Treating divergent series properly has been an ongoing issue in mathematics. However, many of the problems in divergent series stem from the fact that divergent series were discovered prior to having a number system which could handle them. The infinities that resulted from divergent series led to contradictions within the real number system, but these contradictions are largely alleviated with the hyperreal number system. Hyperreal numbers provide a framework for dealing with divergent serie...

  10. 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

  11. Chained Kullback-Leibler Divergences

    Science.gov (United States)

    Pavlichin, Dmitri S.; Weissman, Tsachy

    2017-01-01

    We define and characterize the “chained” Kullback-Leibler divergence minw D(p‖w) + D(w‖q) minimized over all intermediate distributions w and the analogous k-fold chained K-L divergence min D(p‖wk−1) + … + D(w2‖w1) + D(w1‖q) minimized over the entire path (w1,…,wk−1). This quantity arises in a large deviations analysis of a Markov chain on the set of types – the Wright-Fisher model of neutral genetic drift: a population with allele distribution q produces offspring with allele distribution w, which then produce offspring with allele distribution p, and so on. The chained divergences enjoy some of the same properties as the K-L divergence (like joint convexity in the arguments) and appear in k-step versions of some of the same settings as the K-L divergence (like information projections and a conditional limit theorem). We further characterize the optimal k-step “path” of distributions appearing in the definition and apply our findings in a large deviations analysis of the Wright-Fisher process. We make a connection to information geometry via the previously studied continuum limit, where the number of steps tends to infinity, and the limiting path is a geodesic in the Fisher information metric. Finally, we offer a thermodynamic interpretation of the chained divergence (as the rate of operation of an appropriately defined Maxwell’s demon) and we state some natural extensions and applications (a k-step mutual information and k-step maximum likelihood inference). We release code for computing the objects we study. PMID:29130024

  12. 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

  13. 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.

  14. 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

  15. 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

  16. 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 ...

  17. Recombinant proteins from Gallibacterium anatis induces partial protection against heterologous challenge in egg-laying hens

    DEFF Research Database (Denmark)

    Pors, Susanne Elisabeth; Skjerning, Ragnhild Bager; Flachs, Esben M.

    2016-01-01

    Gallibacterium anatis is a Gram-negative bacterium and major cause of salpingitis and peritonitis in egg-laying hens, thereby contributing to decreased egg production and increased mortality among the hens. Due to widespread drug resistance and antigenic diversity, novel prophylactic measures...

  18. 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 ...

  19. Quality of foraging material and the effect on hens feed intake, egg production and - quality

    DEFF Research Database (Denmark)

    Steenfeldt, Sanna; Hammershøj, Marianne

    2010-01-01

    In a project with organic egg laying hens, the effect of different kind of foraging material was studied on feed intake, egg-production and -quality. Udgivelsesdato: August......In a project with organic egg laying hens, the effect of different kind of foraging material was studied on feed intake, egg-production and -quality. Udgivelsesdato: August...

  20. 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 ...

  1. 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

  2. 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

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

    NARCIS (Netherlands)

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

    2010-01-01

    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

  4. 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

  5. Heritability of feather pecking and open-field response of laying hens at two different ages

    NARCIS (Netherlands)

    Rodenburg, T.B.; Buitenhuis, A.J.; Ask, B.; Uitdehaag, K.A.; Koene, P.; Poel, van der J.J.; Bovenhuis, H.

    2003-01-01

    The objective of the current study was to estimate heritabilities. (h(2)) of feather pecking and open-field response of laying hens at two different ages. An F-2 cross, originating from a high and a low feather pecking line of laying hens, was used for the experiment. Each of the 630 birds of the

  6. 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 ...

  7. 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 ...

  8. The prevention and control of feather pecking in laying hens : identifying the underlying principles

    NARCIS (Netherlands)

    Rodenburg, T. B.; van Krimpen, M. M.; de Jong, I. C.; de Haas, E. N.; Kops, M. S.; Riedstra, B. J.; Nordquist, R. E.; Wagenaar, J. P.; Bestman, M.; Nicol, C. J.

    Feather pecking (FP) in laying hens remains an important economic and welfare issue. This paper reviews the literature on causes of FP in laying hens. With the ban on conventional cages in the EU from 2012 and the expected future ban on beak trimming in many European countries, addressing this

  9. 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

  10. 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.

  11. 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 ...

  12. Variation in Phytochemical Composition Reveals Distinct Divergence of Aloe vera (L.) Burm.f. From Other Aloe Species: Rationale Behind Selective Preference of Aloe vera in Nutritional and Therapeutic Use

    Science.gov (United States)

    Dey, Priyankar; Dutta, Somit; Chowdhury, Anurag; Das, Abhaya Prasad; Chaudhuri, Tapas Kumar

    2017-01-01

    In the present study, we have phytochemically characterized 5 different abundant Aloe species, including Aloe vera (L.) Burm.f., using silylation followed by Gas Chromatography-Mass Spectrometry technique and compared the data using multivariate statistical analysis. The results demonstrated clear distinction of the overall phytochemical profile of A vera, highlighted by its divergent spatial arrangement in the component plot. Lowest correlation of the phytochemical profiles were found between A vera and A aristata Haw. (−0.626), whereas highest correlation resided between A aristata and A aspera Haw. (0.899). Among the individual phytochemicals, palmitic acid was identified in highest abundance cumulatively, and carboxylic acids were the most predominant phytochemical species in all the Aloe species. Compared to A vera, linear correlation analysis revealed highest and lowest correlation with A aspera (R 2 = 0.9162) and A aristata (R 2 = 0.6745), respectively. Therefore, A vera demonstrated distinct spatial allocation, reflecting its greater phytochemical variability. PMID:29228808

  13. 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

  14. 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.

  15. Transcutaneous vagus nerve stimulation (tVNS) enhances divergent thinking.

    Science.gov (United States)

    Colzato, Lorenza S; Ritter, Simone M; Steenbergen, Laura

    2018-03-01

    Creativity is one of the most important cognitive skills in our complex and fast-changing world. Previous correlative evidence showed that gamma-aminobutyric acid (GABA) is involved in divergent but not convergent thinking. In the current study, a placebo/sham-controlled, randomized between-group design was used to test a causal relation between vagus nerve and creativity. We employed transcutaneous vagus nerve stimulation (tVNS), a novel non-invasive brain stimulation technique to stimulate afferent fibers of the vagus nerve and speculated to increase GABA levels, in 80 healthy young volunteers. Creative performance was assessed in terms of divergent thinking (Alternate Uses Task) and convergent thinking tasks (Remote Associates Test, Creative Problem Solving Task, Idea Selection Task). Results demonstrate active tVNS, compared to sham stimulation, enhanced divergent thinking. Bayesian analysis reported the data to be inconclusive regarding a possible effect of tVNS on convergent thinking. Therefore, our findings corroborate the idea that the vagus nerve is causally involved in creative performance. Even thought we did not directly measure GABA levels, our results suggest that GABA (likely to be increased in active tVNS condition) supports the ability to select among competing options in high selection demand (divergent thinking) but not in low selection demand (convergent thinking). Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.

  16. 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.

  17. 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.

  18. 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

  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. 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.

  1. 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

  2. Commercial Hy-Line W-36 pullet and laying hen venous blood gas and chemistry profiles utilizing the portable i-STAT®1 analyzer.

    Science.gov (United States)

    Schaal, T P; Arango, J; Wolc, A; Brady, J V; Fulton, J E; Rubinoff, I; Ehr, I J; Persia, M E; O'Sullivan, N P

    2016-02-01

    Venous blood gas and chemistry reference ranges were determined for commercial Hy-Line W-36 pullets and laying hens utilizing the portable i-STAT®1 analyzer and CG8+ cartridges. A total of 632 samples were analyzed from birds between 4 and 110 wk of age. Reference ranges were established for pullets (4 to 15 wk), first cycle laying hens (20 to 68 wk), and second cycle (post molt) laying hens (70 to 110 wk) for the following traits: sodium (Na mmol/L), potassium (K mmol/L), ionized calcium (iCa mmol/L), glucose (Glu mg/dl), hematocrit (Hct% Packed Cell Volume [PCV]), pH, partial pressure carbon dioxide (PCO2 mm Hg), partial pressure oxygen (PO2 mm Hg), total concentration carbon dioxide (TCO2 mmol/L), bicarbonate (HCO3 mmol/L), base excess (BE mmol/L), oxygen saturation (sO2%), and hemoglobin (Hb g/dl). Data were analyzed using ANOVA to investigate the effect of production status as categorized by bird age. Trait relationships were evaluated by linear correlation and their spectral decomposition. All traits differed significantly among pullets and mature laying hens in both first and second lay cycles. Levels for K, iCa, Hct, pH, TCO2, HCO3, BE, sO2, and Hb differed significantly between first cycle and second cycle laying hens. Many venous blood gas and chemistry parameters were significantly correlated. The first 3 eigenvalues explained ∼2/3 of total variation. The first 2 principal components (PC) explained 51% of the total variation and indicated acid-balance and relationship between blood O2 and CO2. The third PC explained 16% of variation and seems to be related to blood iCa. Establishing reference ranges for pullet and laying hen blood gas and chemistry with the i-STAT®1 handheld unit provides a mechanism to further investigate pullet and layer physiology, evaluate metabolic disturbances, and may potentially serve as a means to select breeder candidates with optimal blood gas or chemistry levels on-farm. © The Author 2015. Published by Oxford University

  3. On Hölder Projective Divergences

    KAUST Repository

    Nielsen, Frank

    2017-03-16

    We describe a framework to build distances by measuring the tightness of inequalities and introduce the notion of proper statistical divergences and improper pseudo-divergences. We then consider the Holder ordinary and reverse inequalities and present two novel classes of Holder divergences and pseudo-divergences that both encapsulate the special case of the Cauchy-Schwarz divergence. We report closed-form formulas for those statistical dissimilarities when considering distributions belonging to the same exponential family provided that the natural parameter space is a cone (e.g., multivariate Gaussians) or affine (e.g., categorical distributions). Those new classes of Holder distances are invariant to rescaling and thus do not require distributions to be normalized. Finally, we show how to compute statistical Holder centroids with respect to those divergences and carry out center-based clustering toy experiments on a set of Gaussian distributions which demonstrate empirically that symmetrized Holder divergences outperform the symmetric Cauchy-Schwarz divergence.

  4. On Hölder Projective Divergences

    KAUST Repository

    Nielsen, Frank; Sun, Ke; Marchand-Maillet, Stephane

    2017-01-01

    We describe a framework to build distances by measuring the tightness of inequalities and introduce the notion of proper statistical divergences and improper pseudo-divergences. We then consider the Holder ordinary and reverse inequalities and present two novel classes of Holder divergences and pseudo-divergences that both encapsulate the special case of the Cauchy-Schwarz divergence. We report closed-form formulas for those statistical dissimilarities when considering distributions belonging to the same exponential family provided that the natural parameter space is a cone (e.g., multivariate Gaussians) or affine (e.g., categorical distributions). Those new classes of Holder distances are invariant to rescaling and thus do not require distributions to be normalized. Finally, we show how to compute statistical Holder centroids with respect to those divergences and carry out center-based clustering toy experiments on a set of Gaussian distributions which demonstrate empirically that symmetrized Holder divergences outperform the symmetric Cauchy-Schwarz divergence.

  5. Study of Salmonella Typhimurium infection in laying hens

    Directory of Open Access Journals (Sweden)

    Kapil eChousalkar

    2016-02-01

    Full Text Available Members of Salmonella enterica are frequently involved in egg and egg product related human food poisoning outbreaks worldwide. In Australia, Salmonella Typhimurium is frequently involved in egg and egg product related foodborne illness and Salmonella Mbandaka has also been found to be a contaminant of the layer farm environment. The ability possessed by Salmonella Enteritidis to colonise reproductive organs and contaminate developing eggs has been well described. However, there are few studies investigating this ability for Salmonella Typhimurium. The hypothesis of this study was that the Salmonella Typhimurium can colonise the gut for a prolonged period of time and that horizontal infection through feces is the main route of egg contamination. At 14 weeks of age hens were orally infected with either S. Typhimurium PT 9 or S. Typhimurium PT 9 and Salmonella Mbandaka. Salmonella shedding in feces and eggs was monitored for 15 weeks post infection. Egg shell surface and internal contents of eggs laid by infected hens were cultured independently for detection of Salmonella spp. The mean Salmonella load in feces ranged from 1.54 to 63.35 and 0.31 to 98.38 most probable number/g (MPN/g in the S. Typhimurium and S. Typhimurium + S. Mbandaka group respectively. No correlation was found between mean fecal Salmonella load and frequency of egg shell contamination. Egg shell contamination was higher in S. Typhimurium + S. Mbandaka infected group (7.2% Typhimurium, 14.1% Mbandaka compared to birds infected with S. Typhimurium (5.66% however, co-infection had no significant impact on egg contamination by S. Typhimurium. Throughout the study Salmonella was not recovered from internal contents of eggs laid by hens. Salmonella was isolated from different segments of oviduct of hens from both the groups, however pathology was not observed on microscopic examination. This study investigated Salmonella shedding for up to 15 weeks p.i which is a longer period of

  6. Genetic Divergence in Sugarcane Genotypes

    OpenAIRE

    Tahir, Mohammad; Rahman, Hidayatur; Gul, Rahmani; Ali, Amjad; Khalid, Muhammad

    2012-01-01

    To assess genetic divergence of sugarcane germplasm, an experiment comprising 25 sugarcane genotypes was conducted at Sugar Crops Research Institute (SCRI), Mardan, Khyber Pakhtunkhwa, Pakistan, in quadruple lattice design during 2008-09. Among the 14 parameters evaluated, majority exhibited significant differences while some showed nonsignificant mean squares. The initial correlation matrix revealed medium to high correlations. Principal Component Analysis (PCA) showed that there were two pr...

  7. Computer recognition of divergences in Feynman graphs

    Energy Technology Data Exchange (ETDEWEB)

    Calmet, J

    1973-05-01

    The program described recognizes whether or not a graph is divergent. It determines the kind of the divergences found: vacuum polarizations, electron self energies and vertices. it does not consider infrared divergences. The programming language used is REDUCE. A LISP version is also available. The nature of the divergences and their counter terms was extensively used to write down this program, therefore it is limited to the case of quantum electrodynamics. (auth)

  8. 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.

  9. Genetic divergence of tomato subsamples

    Directory of Open Access Journals (Sweden)

    André Pugnal Mattedi

    2014-02-01

    Full Text Available Understanding the genetic variability of a species is crucial for the progress of a genetic breeding program and requires characterization and evaluation of germplasm. This study aimed to characterize and evaluate 101 tomato subsamples of the Salad group (fresh market and two commercial controls, one of the Salad group (cv. Fanny and another of the Santa Cruz group (cv. Santa Clara. Four experiments were conducted in a randomized block design with three replications and five plants per plot. The joint analysis of variance was performed and characteristics with significant complex interaction between control and experiment were excluded. Subsequently, the multicollinearity diagnostic test was carried out and characteristics that contributed to severe multicollinearity were excluded. The relative importance of each characteristics for genetic divergence was calculated by the Singh's method (Singh, 1981, and the less important ones were excluded according to Garcia (1998. Results showed large genetic divergence among the subsamples for morphological, agronomic and organoleptic characteristics, indicating potential for genetic improvement. The characteristics total soluble solids, mean number of good fruits per plant, endocarp thickness, mean mass of marketable fruit per plant, total acidity, mean number of unmarketable fruit per plant, internode diameter, internode length, main stem thickness and leaf width contributed little to the genetic divergence between the subsamples and may be excluded in future studies.

  10. 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.

  11. Genomic islands of divergence are not affected by geography of speciation in sunflowers.

    Science.gov (United States)

    Renaut, S; Grassa, C J; Yeaman, S; Moyers, B T; Lai, Z; Kane, N C; Bowers, J E; Burke, J M; Rieseberg, L H

    2013-01-01

    Genomic studies of speciation often report the presence of highly differentiated genomic regions interspersed within a milieu of weakly diverged loci. The formation of these speciation islands is generally attributed to reduced inter-population gene flow near loci under divergent selection, but few studies have critically evaluated this hypothesis. Here, we report on transcriptome scans among four recently diverged pairs of sunflower (Helianthus) species that vary in the geographical context of speciation. We find that genetic divergence is lower in sympatric and parapatric comparisons, consistent with a role for gene flow in eroding neutral differences. However, genomic islands of divergence are numerous and small in all comparisons, and contrary to expectations, island number and size are not significantly affected by levels of interspecific gene flow. Rather, island formation is strongly associated with reduced recombination rates. Overall, our results indicate that the functional architecture of genomes plays a larger role in shaping genomic divergence than does the geography of speciation.

  12. Speciation in rapidly diverging systems: lessons from Lake Malawi.

    Science.gov (United States)

    Danley, P D; Kocher, T D

    2001-05-01

    Rapid evolutionary radiations provide insight into the fundamental processes involved in species formation. Here we examine the diversification of one such group, the cichlid fishes of Lake Malawi, which have radiated from a single ancestor into more than 400 species over the past 700 000 years. The phylogenetic history of this group suggests: (i) that their divergence has proceeded in three major bursts of cladogenesis; and (ii) that different selective forces have dominated each cladogenic event. The first episode resulted in the divergence of two major lineages, the sand- and rock-dwellers, each adapted to a major benthic macrohabitat. Among the rock-dwellers, competition for trophic resources then drove a second burst of cladogenesis, which resulted in the differentiation of trophic morphology. The third episode of cladogenesis is associated with differentiation of male nuptial colouration, most likely in response to divergent sexual selection. We discuss models of speciation in relation to this observed pattern. We advocate a model, divergence with gene flow, which reconciles the disparate selective forces responsible for the diversification of this group and suggest that the nonadaptive nature of the tertiary episode has significantly contributed to the extraordinary species richness of this group.

  13. Sufficient Statistics for Divergence and the Probability of Misclassification

    Science.gov (United States)

    Quirein, J.

    1972-01-01

    One particular aspect is considered of the feature selection problem which results from the transformation x=Bz, where B is a k by n matrix of rank k and k is or = to n. It is shown that in general, such a transformation results in a loss of information. In terms of the divergence, this is equivalent to the fact that the average divergence computed using the variable x is less than or equal to the average divergence computed using the variable z. A loss of information in terms of the probability of misclassification is shown to be equivalent to the fact that the probability of misclassification computed using variable x is greater than or equal to the probability of misclassification computed using variable z. First, the necessary facts relating k-dimensional and n-dimensional integrals are derived. Then the mentioned results about the divergence and probability of misclassification are derived. Finally it is shown that if no information is lost (in x = Bz) as measured by the divergence, then no information is lost as measured by the probability of misclassification.

  14. 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.

  15. 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.

  16. 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.

  17. Process model simulations of the divergence effect

    Science.gov (United States)

    Anchukaitis, K. J.; Evans, M. N.; D'Arrigo, R. D.; Smerdon, J. E.; Hughes, M. K.; Kaplan, A.; Vaganov, E. A.

    2007-12-01

    We explore the extent to which the Vaganov-Shashkin (VS) model of conifer tree-ring formation can explain evidence for changing relationships between climate and tree growth over recent decades. The VS model is driven by daily environmental forcing (temperature, soil moisture, and solar radiation), and simulates tree-ring growth cell-by-cell as a function of the most limiting environmental control. This simplified representation of tree physiology allows us to examine using a selection of case studies whether instances of divergence may be explained in terms of changes in limiting environmental dependencies or transient climate change. Identification of model-data differences permits further exploration of the effects of tree-ring standardization, atmospheric composition, and additional non-climatic factors.

  18. 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.

  19. 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.

  20. Growth divergence: a challenging opportunity for dendrochronology

    Science.gov (United States)

    Buras, Allan; Sass-Klaassen, Ute; Wilmking, Martin

    2017-04-01

    Dendrochronology is an essential cornerstone of paleoclimatology and the evaluation of climate change impacts on forest ecosystems. However, a growing body of literature indicates that the standard dendrochronological approach may too rigorously neglect individualistic tree-growth (e.g. Wilmking et al., 2004, Buras et al., 2016). Amongst others, these studies showed convincing evidence that individual trees of the same species sampled at one site expressed different long-term growth patterns and therefore differing climate-growth relationships. This phenomenon is commonly termed growth divergence (GD) and possibly weakens our ability to correctly estimate past climate variability as discussed in the context of the so-called divergence phenomenon (D'Arrigo et al., 2008). In this context, climate change may naturally select for trees on the stand-level which are better adapted to future conditions. Although GD has been reported for several sites, the standard dendrochronological approach yet does not consider the existence of GD. A possible reason for this methodological persistence is the lack of detailed information on the frequency, magnitude, and impact of GD occurrence. To assess GD occurrence and related tree-individual variations in climate-growth response we conducted a global GD study by using 134 ring-width data representing 52 tree species and 16 genera distributed over 115 sites across 22 countries. Our analyses clearly reveal GD to be a common phenomenon as occurring in 85 % of all sites. GD was clearly related to the degree of tree-individual differences in climate-growth response. Respective transfer functions which appropriately accounted for GD by selection of tree-cohorts with a high share of long-term variance on average increased the precision and stability of tree-ring based climate reconstructions. Concluding, incorporation of GD assessments into the dendrochronological approach has a strong potential to improve the precision of our predictions

  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. 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.

  3. Immune cells in the normal ovary and spontaneous ovarian tumors in the laying hen (Gallus domesticus) model of human ovarian cancer.

    Science.gov (United States)

    Bradaric, Michael J; Penumatsa, Krishna; Barua, Animesh; Edassery, Seby L; Yu, Yi; Abramowicz, Jacques S; Bahr, Janice M; Luborsky, Judith L

    2013-01-01

    Spontaneous ovarian cancer in chickens resembles human tumors both histologically and biochemically. The goal was to determine if there are differences in lymphocyte content between normal ovaries and ovarian tumors in chickens as a basis for further studies to understand the role of immunity in human ovarian cancer progression. Hens were selected using grey scale and color Doppler ultrasound to determine if they had normal or tumor morphology. Cells were isolated from ovaries (n = 6 hens) and lymphocyte numbers were determined by flow cytometry using antibodies to avian CD4 and CD8 T and B (Bu1a) cells. Ovarian sections from another set of hens (n = 26) were assessed to verify tumor type and stage and to count CD4, CD8 and Bu1a immunostained cells by morphometric analysis. T and B cells were more numerous in ovarian tumors than in normal ovaries by flow cytometry and immunohistochemistry. There were less CD4+ cells than CD8+ and Bu1a+ cells in normal ovaries or ovarian tumors. CD8+ cells were the dominant T cell sub-type in both ovarian stroma and in ovarian follicles compared to CD4+ cells. Bu1a+ cells were consistently found in the stroma of normal ovaries and ovarian tumors but were not associated with follicles. The number of immune cells was highest in late stage serous tumors compared to endometrioid and mucinous tumors. The results suggest that similar to human ovarian cancer there are comparatively more immune cells in chicken ovarian tumors than in normal ovaries, and the highest immune cell content occurs in serous tumors. Thus, this study establishes a foundation for further study of tumor immune responses in a spontaneous model of ovarian cancer which will facilitate studies of the role of immunity in early ovarian cancer progression and use of the hen in pre-clinical vaccine trials.

  4. Statistical inference based on divergence measures

    CERN Document Server

    Pardo, Leandro

    2005-01-01

    The idea of using functionals of Information Theory, such as entropies or divergences, in statistical inference is not new. However, in spite of the fact that divergence statistics have become a very good alternative to the classical likelihood ratio test and the Pearson-type statistic in discrete models, many statisticians remain unaware of this powerful approach.Statistical Inference Based on Divergence Measures explores classical problems of statistical inference, such as estimation and hypothesis testing, on the basis of measures of entropy and divergence. The first two chapters form an overview, from a statistical perspective, of the most important measures of entropy and divergence and study their properties. The author then examines the statistical analysis of discrete multivariate data with emphasis is on problems in contingency tables and loglinear models using phi-divergence test statistics as well as minimum phi-divergence estimators. The final chapter looks at testing in general populations, prese...

  5. Effect of heat exposure on gene expression of feed intake regulatory peptides in laying hens.

    Science.gov (United States)

    Song, Zhigang; Liu, Lei; Sheikhahmadi, Ardashir; Jiao, Hongchao; Lin, Hai

    2012-01-01

    The aim of this paper was to investigate the effect of heat stress on the regulation of appetite-associated genes in laying hens. Forty eight laying hens were randomly divided into two circumstances: high (31 ± 1.5°C; relative humidity, 82.0 ± 2.2%) or normal (20 ± 2°C, control; relative humidity, 60.1 ± 4.5%) ambient environment. Heat stress decreased body weight gain (P feed intake (P feed efficiency (P feed intake in laying hens under high ambient temperature.

  6. 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...

  7. Effect of Free-range Rearing on Meat Composition, Physical Properties and Sensory Evaluation in Taiwan Game Hens.

    Science.gov (United States)

    Lin, Cheng-Yung; Kuo, Hsiao-Yun; Wan, Tien-Chun

    2014-06-01

    Experiments were conducted to evaluate the effect of an outdoor-grazed raising model on meat composition, physical properties and sensory attributes of Taiwan game hens. Six hundred 1-d old female chicks were raised on a floor for 8 weeks. On day 57, 600 healthy birds, with similar body weight, were selected and randomly assigned to three treatment groups (cage, floor-pen and free-range). The results showed that different feeding models had no effect on drip loss, cooking loss, moisture, crude protein, crude fat, crude ash, zinc and calorie contents in breast meat and moisture content in thigh meat. The free-range group had the lowest fat content in both breast and thigh meat, and the lowest calorie content in thigh meat. The firmness and toughness in both thigh and breast of the free-range group were the highest values (pmeat and total collagen content in breast meat of the free-range group were significantly higher than those of the cage-feeding group (pmeat sensory scores of flavor, chewiness and overall acceptability of both thigh and breast meat of the free-range group were significantly (pgame hens of the free-range feeding model displayed well-received carcass traits and meat quality, with higher scores for flavor, chewiness and overall acceptability for greater sensory satisfaction in both breast and thigh meat. In addition, the thigh meat contained high protein and total collage but low fat, offering a healthier diet choice.

  8. Ultraviolet divergences and supersymmetric theories

    International Nuclear Information System (INIS)

    Sagnotti, A.

    1984-09-01

    This article is closely related to the one by Ferrara in these same Proceedings. It deals with what is perhaps the most fascinating property of supersymmetric theories, their improved ultraviolet behavior. My aim here is to present a survey of the state of the art as of August, 1984, and a somewhat more detailed discussion of the breakdown of the superspace power-counting beyond N = 2 superfields. A method is also described for simplifying divergence calculations that uses the locality of subtracted Feynman integrals. 74 references

  9. Ultraviolet divergences of Einstein gravity

    International Nuclear Information System (INIS)

    Goroff, M.H.

    1986-01-01

    The author discuss a two-loop calculation showing that the S matrix of Einstein's theory of gravity contains nonrenormalizable ultraviolet divergences in four dimension. The author discusses the calculation in both background field and normal field theory. The author describes a new method for dealing with ghost fields in gauge theories by combining them with suitable extensions of the gauge fields in higher dimensions. The author shows how using subtracted integrals in the calculation of higher loop graphs simplifies the calculation in the background field method by eliminating the need for mixed counterterms. Finally, the author makes some remarks about the implications of the result for supergravity theories

  10. 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.

  11. Early-life sensitization to hen's egg predicts asthma and rhinoconjunctivitis at 14 years of age

    DEFF Research Database (Denmark)

    Christiansen, Elisabeth Soegaard; Kjaer, Henrik Fomsgaard; Eller, Esben

    2017-01-01

    to groups of and to individual allergens and asthma and RC at 6 and 14 years compared to a reference group with no sensitization. RESULTS: Both transient and persistent early-life sensitization to cow's milk or hen's egg proteins were associated with asthma (aOR 3.99(1.41-11.32) and 5.95(1.78-19.92)) and RC...... (aOR 2.94(1.19-7.28) and 6.18(1.86-20.53)) at 14 years, this association being driven mainly by sensitization to hen's egg. Transient early-life sensitization to HDM had increased risk of asthma (aOR 3.80(1.17-12.41)) at 14 years. CONCLUSIONS: Early transient and persistent IgE sensitization to hen......'s egg was associated with asthma and RC at 14 years. Furthermore, sensitization to HDM was associated with asthma at 14 years. This article is protected by copyright. All rights reserved....

  12. Verteerbaarheid van biologisch geteelde veevoedergrondstoffen bij leghennen = Digestibility of organic processed feed ingredients in laying hens

    NARCIS (Netherlands)

    Krimpen, van M.M.; Diepen, van J.T.M.; Reuvekamp, B.F.J.; Harn, van 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.

  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. 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...

  15. 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.

  16. Divergent thinking and constructing episodic simulations.

    Science.gov (United States)

    Addis, Donna Rose; Pan, Ling; Musicaro, Regina; Schacter, Daniel L

    2016-01-01

    Divergent thinking likely plays an important role in simulating autobiographical events. We investigated whether divergent thinking is differentially associated with the ability to construct detailed imagined future and imagined past events as opposed to recalling past events. We also examined whether age differences in divergent thinking might underlie the reduced episodic detail generated by older adults. The richness of episodic detail comprising autobiographical events in young and older adults was assessed using the Autobiographical Interview. Divergent thinking abilities were measured using the Alternative Uses Task. Divergent thinking was significantly associated with the amount of episodic detail for imagined future events. Moreover, while age was significantly associated with imagined episodic detail, this effect was strongly related to age-related changes in episodic retrieval rather than divergent thinking.

  17. 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.

  18. 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.

  19. 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.

  20. Traits and behaviour affecting social status in red junglefowl (Gallus gallus) hens

    OpenAIRE

    Lindblom, Emelie

    2012-01-01

    Social status is commonly established among individuals within groups of animals. Despite this common characteristic of social animals it is still unclear how individuals establish their status. I investigated the relationships between morphology, posture and behaviours with social status in red junglefowl hens. The hens tested were measured (weight, comb length, comb height and tarsus length) and exposed to three different behavioural tests (novel arena, novel object and interaction test). N...

  1. 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.

  2. 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.

  3. 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.

  4. Response analysis of the dynamic excitation of hen eggs

    Directory of Open Access Journals (Sweden)

    Libor Severa

    2007-01-01

    Full Text Available Commercially produced hen eggs have been tested by means of dynamic excitation of the egg-shells with following analysis of their response. The falling steel ball have been chosen as a exciting instrument and the laser vibrometer have been used as a measuring device for the egg response. The reproductibility of the experiments has been relatively high and the surface velocity has been found to be significantly dependent on the position around the meridian. Analysed frequency spectrum has shown the peak frequency and frequency history. Proposed numerical model has demonstrated reasonable agreement with experimental results and can be used as an effective tool in modelling of analogous or similar experiments.

  5. The response to selection for broad male response to female sex pheromone and its implications for divergence in close-range mating behavior in the European corn borer moth, Ostrinia nubilalis.

    Science.gov (United States)

    Droney, David C; Musto, Callie J; Mancuso, Katie; Roelofs, Wendell L; Linn, Charles E

    2012-12-01

    Coordinated sexual communication systems, seen in many species of moths, are hypothesized to be under strong stabilizing natural selection. Stabilized communication systems should be resistant to change, but there are examples of species/populations that show great diversification. A possible solution is that it is directional sexual selection on variation in male response that drives evolution. We tested a component of this model by asking whether 'rare' males (ca. 5 % of all males in a population) of the European corn borer moth (ECB), Ostrinia nubilalis, that respond to the sex pheromones of both ECB and a different Ostrinia species (O. furnacalis, the Asian corn borer, ACB), might play an important role in diversification. We specifically tested, via artificial selection, whether this broad male response has an evolvable genetic component. We increased the frequency of broad male response from 5 to 70 % in 19 generations, showing that broad-responding males could be important for the evolution of novel communication systems in ECB. We did not find a broader range of mating acceptance of broad males by females of the base population, however, suggesting that broad response would be unlikely to increase in frequency without the involvement of other factors. However, we found that ECB selection-line females accepted a broader range of courting males, including those of ACB, than did females of the base population. Thus, a genetic correlation exists between broad, long-range response to female sex pheromone and the breadth of female acceptance of males at close range. These results are discussed in the context of evolution of novel communication systems in Ostrinia.

  6. 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.

  7. 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.

  8. 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)

  9. 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.

  10. 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.

  11. 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.

  12. Genetic divergence analysis in pumpkin

    International Nuclear Information System (INIS)

    Quamruzzaman, A.M.; Moniruzzaman, M.

    2013-01-01

    Genetic divergence among 18 punpkin genotypes was estimated using Mahalanohis's 1) statistic. Altogether lour clusters were formed where cluster I contained the highest number of genotypes (8) and cluster II contained the lowest (I). The highest intra-cluster distance was observed h.ir cluster I (0.83 I) and the lowest for clustcr IV (0.65 I). The highest inter-cluster distance was observed between cluster I and 11(24.346). Cluster II recorded the highest mean for fruit number/plant, TSS, fruit yield and niinitnuiii III cavity length and cavity diameter. Cluster III had the second highest mean for fruit diameter, fruit number/plant, individual unit weight, fruit yield and the fewest number of days to 1st Female flowering, earliness being a desirable trait. These crosses may produce new recombinants with desirable traits. (author)

  13. Divergence operator and related inequalities

    CERN Document Server

    Acosta, Gabriel

    2017-01-01

    This Brief is mainly devoted to two classical and related results: the existence of a right inverse of the divergence operator and the so-called Korn Inequalities. It is well known that both results are fundamental tools in the analysis of some classic differential equations, particularly in those arising in fluid dynamics and elasticity. Several connections between these two topics and improved Poincaré inequalities are extensively treated. From simple key ideas the book is growing smoothly in complexity. Beginning with the study of these problems on star-shaped domains the arguments are extended first to John domains and then to Hölder α domains where the need of weighted spaces arises naturally. In this fashion, the authors succeed in presenting in an unified and concise way several classic and recent developments in the field. These features certainly makes this Brief useful for students, post-graduate students, and researchers as well.

  14. Ramanujan summation of divergent series

    CERN Document Server

    Candelpergher, Bernard

    2017-01-01

    The aim of this monograph is to give a detailed exposition of the summation method that Ramanujan uses in Chapter VI of his second Notebook. This method, presented by Ramanujan as an application of the Euler-MacLaurin formula, is here extended using a difference equation in a space of analytic functions. This provides simple proofs of theorems on the summation of some divergent series. Several examples and applications are given. For numerical evaluation, a formula in terms of convergent series is provided by the use of Newton interpolation. The relation with other summation processes such as those of Borel and Euler is also studied. Finally, in the last chapter, a purely algebraic theory is developed that unifies all these summation processes. This monograph is aimed at graduate students and researchers who have a basic knowledge of analytic function theory.

  15. Beam divergence scaling in neutral beam injectors

    International Nuclear Information System (INIS)

    Holmes, A.J.T.

    1976-01-01

    One of the main considerations in the design of neutral beam injectors is to monimize the divergence of the primary ion beam and hence maximize the beam transport and minimize the input of thermal gas. Experimental measurements of the divergence of a cylindrical ion beam are presented and these measurements are used to analyze the major components of ion beam divergence, namely: space charge expansion, gas-ion scattering, emittance and optical aberrations. The implication of these divergence components in the design of a neutral beam injector system is discussed and a method of maximizing the beam current is described for a given area of source plasma

  16. Guises and disguises of quadratic divergences

    Energy Technology Data Exchange (ETDEWEB)

    Cherchiglia, A.L., E-mail: adriano@fisica.ufmg.br [Departamento de Física, ICEx, Universidade Federal de Minas Gerais, P.O. BOX 702, 30.161-970, Belo Horizonte, MG (Brazil); Vieira, A.R., E-mail: arvieira@fisica.ufmg.br [Departamento de Física, ICEx, Universidade Federal de Minas Gerais, P.O. BOX 702, 30.161-970, Belo Horizonte, MG (Brazil); Hiller, Brigitte, E-mail: brigitte@teor.fis.uc.pt [Departamento de Física, Faculdade de Ciências e Tecnologia, Universidade de Coimbra, 3004-516 Coimbra (Portugal); Baêta Scarpelli, A.P., E-mail: scarpelli.apbs@dpf.gov.br [Setor Técnico-Científico, Departamento de Polícia Federal, Rua Hugo D’Antola, 95 - Lapa, São Paulo (Brazil); Sampaio, Marcos, E-mail: marcos.sampaio@durham.ac.uk [Departamento de Física, ICEx, Universidade Federal de Minas Gerais, P.O. BOX 702, 30.161-970, Belo Horizonte, MG (Brazil); Centre for Particle Theory, Department of Mathematical Sciences, Durham University, South Road Durham DH1 3LE (United Kingdom)

    2014-12-15

    In this contribution, we present a new perspective on the control of quadratic divergences in quantum field theory, in general, and in the Higgs naturalness problem, in particular. Our discussion is essentially based on an approach where UV divergences are parameterized, after being reduced to basic divergent integrals (BDI) in one internal momentum, as functions of a cutoff and a renormalization group scale λ. We illustrate our proposal with well-known examples, such as the gluon vacuum self energy of QCD and the Higgs decay in two photons within this approach. We also discuss frameworks in effective low-energy QCD models, where quadratic divergences are indeed fundamental.

  17. Divergence Palsy due to Divalproex and Oxcarbazepine.

    Science.gov (United States)

    Bouffard, Marc Albert; Caplan, Louis R; Torun, Nurhan

    This case series is the first to describe divergence palsy as an adverse effect of antiepileptic drug use. Diplopia is a common adverse effect of antiepileptic drugs, but no explanatory motility deficit has ever been reported. We present 2 patients, 1 on oxcarbazepine and 1 on divalproex, each with a normal examination result between spells and divergency palsy when symptomatic. Discontinuation of the antiepileptic medication led to resolution of the episodes in both cases. Rechallenge with the offending agent after washout in one patient resulted in recurrence of diplopia and divergence palsy, both resolving after subsequent withdrawal of the antiepileptic. Antiepileptic drugs may cause divergence palsy.

  18. Differentiation of ruminal bacterial species by enzyme-linked immunosorbent assay using egg yolk antibodies from immunized chicken hens.

    OpenAIRE

    Ricke, S C; Schaefer, D M; Cook, M E; Kang, K H

    1988-01-01

    Cross-reactivity among four species of ruminal bacteria was examined by using egg yolk antibodies from immunized Leghorn laying hens and an enzyme-linked-immunosorbent assay. The effects of the four species on the hens were compared on various days postimmunization. Hens injected with the same bacterial species had similar apparent antibody levels over the entire postimmunization period, but only Bacteroides ruminicola B1(4) and Selenomonas ruminantium D antigens elicited early increases in a...

  19. Genetic correlation between traits in the ESALQ-PB1 maize population divergently selected for tassel size and ear height Correlação genética entre caracteres na população de milho ESALQ-PB1 após seleção divergente para tamanho do pendão e altura da espiga

    Directory of Open Access Journals (Sweden)

    Austeclínio Lopes Farias Neto

    2001-03-01

    Full Text Available Full-sib and selfed (S1 progenies were obtained from sub-populations of ESALQ-PB1, divergently selected for tassel size (T+ and T- and ear height (E+ and E-, and used for estimating genetic and phenotypic correlation coefficients between traits. The analyzed traits were: EW- total ear weight (g/plant, PH- plant height (cm, EH- ear height (cm, TB- tassel branch number and TL- tassel length. The highest genetic (rG and phenotypic (rF correlation was observed for the combination PH x EH, as expected, with average of 0.800 and 0.778, respectively over sub-populations and locations. It is apparent that divergent selection for tassel size did not affect greatly the correlation between PH and EH in the full sib progenies, but in the inbred progenies the correlation was smaller in the sub-population selected for larger tassels. Genetic correlation between PH and EH with tassel traits was always positive but ranged from 0.020 to 0.668 in Piracicaba and from 0.06 to 0.309 in Rio Verde. Genetic correlation between PH and EH with yield (EW also was positive in the range of 0.087 to 0.503. EH showed higher correlation with EW in relation to PH x EW and differences were larger in the sub-populations divergently selected for ear height. Correlation between tassel traits with other traits was positive in most of instances and a lack of consistency was observed among sub-populations. Generally the coefficients of genetic and phenotypic correlation differed substantially from the estimates in the base population ESALQ-PB1 before divergent selection for tassel size and ear placement. Divergent selection affected the correlation between traits under unpredicted and varying magnitudes.Progênies de irmãos germanos e de autofecundação (S1 foram obtidas de sub-populações de ESALQ-PB1 após seleção divergente para tamanho do pendão (T+ e T- e altura da espiga (E+ e E- e utilizadas para estimar os coeficientes de correlação genética e fenotípica entre

  20. Pedigree and genomic analyses of feed consumption and residual feed intake in laying hens.

    Science.gov (United States)

    Wolc, Anna; Arango, Jesus; Jankowski, Tomasz; Settar, Petek; Fulton, Janet E; O'Sullivan, Neil P; Fernando, Rohan; Garrick, Dorian J; Dekkers, Jack C M

    2013-09-01

    Efficiency of production is increasingly important with the current escalation of feed costs and demands to minimize the environmental footprint. The objectives of this study were 1) to estimate heritabilities for daily feed consumption and residual feed intake and their genetic correlations with production and egg-quality traits; 2) to evaluate accuracies of estimated breeding values from pedigree- and marker-based prediction models; and 3) to localize genomic regions associated with feed efficiency in a brown egg layer line. Individual feed intake data collected over 2-wk trial periods were available for approximately 6,000 birds from 8 generations. Genetic parameters were estimated with a multitrait animal model; methods BayesB and BayesCπ were used to estimate marker effects and find genomic regions associated with feed efficiency. Using pedigree information, feed efficiency was found to be moderately heritable (h(2) = 0.46 for daily feed consumption and 0.47 for residual feed intake). Hens that consumed more feed and had greater residual feed intake (lower efficiency) had a genetic tendency to lay slightly more eggs with greater yolk weights and albumen heights. Regions on chromosomes 1, 2, 4, 7, 13, and Z were found to be associated with feed intake and efficiency. The accuracy from genomic prediction was higher and more persistent (better maintained across generations) than that from pedigree-based prediction. These results indicate that genomic selection can be used to improve feed efficiency in layers.

  1. k-Means Clustering with Hölder Divergences

    KAUST Repository

    Nielsen, Frank; Sun, Ke; Marchand-Maillet, Sté phane

    2017-01-01

    We introduced two novel classes of Hölder divergences and Hölder pseudo-divergences that are both invariant to rescaling, and that both encapsulate the Cauchy-Schwarz divergence and the skew Bhattacharyya divergences. We review the elementary concepts of those parametric divergences, and perform a clustering analysis on two synthetic datasets. It is shown experimentally that the symmetrized Hölder divergences consistently outperform significantly the Cauchy-Schwarz divergence in clustering tasks.

  2. k-Means Clustering with Hölder Divergences

    KAUST Repository

    Nielsen, Frank

    2017-10-24

    We introduced two novel classes of Hölder divergences and Hölder pseudo-divergences that are both invariant to rescaling, and that both encapsulate the Cauchy-Schwarz divergence and the skew Bhattacharyya divergences. We review the elementary concepts of those parametric divergences, and perform a clustering analysis on two synthetic datasets. It is shown experimentally that the symmetrized Hölder divergences consistently outperform significantly the Cauchy-Schwarz divergence in clustering tasks.

  3. Lexicographic presentation of grammatical divergence in Sesotho ...

    African Journals Online (AJOL)

    Relying on existing insights from the field of theoretical lexicography this article gives an innovative application to the relation of divergence by introducing the notion of grammatical divergence. In bilingual dictionaries with English and Sesotho sa Leboa as language pair lexicographers are confronted with a real challenge ...

  4. Divergent Thinking and Age-Related Changes

    Science.gov (United States)

    Palmiero, Massimiliano; Di Giacomo, Dina; Passafiume, Domenico

    2014-01-01

    Aging can affect cognition in different ways. The extent to which aging affects divergent thinking is unclear. In this study, younger and older adults were compared at the performance on the Torrance Test of Creative Thinking in visual and verbal form. Results showed that older adults can think divergently as younger participants, although they…

  5. Ecological Divergence and the Origins of Intrinsic Postmating Isolation with Gene Flow

    Directory of Open Access Journals (Sweden)

    Aneil F. Agrawal

    2011-01-01

    Full Text Available The evolution of intrinsic postmating isolation has received much attention, both historically and in recent studies of speciation genes. Intrinsic isolation often stems from between-locus genetic incompatibilities, where alleles that function well within species are incompatible with one another when brought together in the genome of a hybrid. It can be difficult for such incompatibilities to originate when populations diverge with gene flow, because deleterious genotypic combinations will be created and then purged by selection. However, it has been argued that if genes underlying incompatibilities are themselves subject to divergent selection, then they might overcome gene flow to diverge between populations, resulting in the origin of incompatibilities. Nonetheless, there has been little explicit mathematical exploration of such scenarios for the origin of intrinsic incompatibilities during ecological speciation with gene flow. Here we explore theoretical models for the origin of intrinsic isolation where genes subject to divergent natural selection also affect intrinsic isolation, either directly or via linkage disequilibrium with other loci. Such genes indeed overcome gene flow, diverge between populations, and thus result in the evolution of intrinsic isolation. We also examine barriers to neutral gene flow. Surprisingly, we find that intrinsic isolation sometimes weakens this barrier, by impeding differentiation via ecologically based divergent selection.

  6. Individual differences in personality in laying hens are related to learning a colour cue association.

    Science.gov (United States)

    de Haas, Elske N; Lee, Caroline; Hernandez, Carlos E; Naguib, Marc; Rodenburg, T Bas

    2017-01-01

    Personality can influence how animals perceive and learn cues. The behaviour and physiological responses animals show during stressful events is indicative of their personality. Acute induced stress prior to a cognitive test are known to affect the judgement of a stimulus, but personality of an individual could also affect learning of a specific cognitive paradigm. Here, we assessed if adult laying hens' behaviour and physiological responses, as indicators of their personality, were related to their cognitive performance. We assessed their behavioural responses to a tonic immobility test, an open field test, and a manual restraint test, and measured plasma corticosterone levels after manual restraint. After that, hens (n=20) were trained in a pre-set training schedule to associate a colour-cue with a reward. In a two-choice go-go test, hens needed to choose between a baited or non-baited food container displayed randomly on the left or right side of an arena. Success in learning was related to personality, with better performance of hens which showed a reactive personality type by a long latency to walk, struggle or vocalize during the tests. Only eight out of 20 hens reached the training criteria. The non-learners showed a strong side preference during all training days. Side preferences were strong in hens with high levels of plasma corticosterone and with a long duration of tonic immobility, indicating that fearful, stress-sensitive hens are more prone to develop side biases. Our results show that learning can be hindered by side biases, and fearful animals with a more proactive personality type are more sensitive to develop such biases. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. 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.

  8. Immunological status of the progeny of breeder hens kept on ochratoxin A (OTA)-contaminated feed.

    Science.gov (United States)

    Zahoor-Ul-Hassan; Khan, Muhammad Zargham; Khan, Ahrar; Javed, Ijaz; Saleemi, Muhammad Kashif

    2011-06-01

    This study aimed to evaluate the immunological status of the progeny of breeder hens kept on ochratoxin A (OTA)-contaminated feed. For this purpose, 84 White Leghorn (WL) layer breeder hens (40-weeks-of-age) were divided into seven groups (A-G). Hens in the Group A were fed a commercial layer ration while those in Groups B-G were kept on a diet amended with 0.1, 0.5, 1.0, 3.0, 5.0, or 10.0 mg OTA/kg, respectively, for 3 weeks. Fertile eggs were set for hatching on the weekly basis to get the progeny of each week separately. Hatched chicks (n = 10 from each group) were euthanized at Day 14 of age, and their immunological organs weighed and fixed in neutral buffered formalin. An indirect immunoperoxidase method was applied to study the frequency of immunoglobulin(s)-bearing cells in the spleen and bursa of Fabricius from these progeny. From other chicks within each set, at Day 16 of age, lymphoblastogenic responses against an intradermal administration of phytohemagglutinin (PHA-P) were determined. Relative weights of the bursa of Fabricius and of the thymus were significantly lower in the progeny of hens fed OTA-contaminated diet for 14 and 21 days. The frequencies of IgA-, IgG-, and IgM-bearing cells were also significantly (P ≤ 0.05) lower in the bursa of Fabricius and spleen of the progeny chicks obtained from dams fed the OTA-mixed diet. Progeny chicks obtained from the breeder hens fed higher doses of OTA showed significantly lower responses to PHA-P than did counterpart chicks from control hens. The findings of this study suggested that there were immunosuppressive effects from OTA in the progeny obtained from breeder hens kept on OTA-contaminated diets.

  9. 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.

  10. The effect of the clove essential oil to the production and quality of lyaing hens eggs

    Directory of Open Access Journals (Sweden)

    Henrieta Arpášová

    2017-05-01

    Full Text Available The aim of this study was to determinate the effect of the clove (Syzygium aromaticum essential oil to the egg production parameters and egg quality of laying hens. A total of 40 Lohmann Brown laying hens were divided into 4 groups (n = 10. The laying hens were fed 20 weeks ad libitum. The control group was fed with complete feed mixtures without additives. The first group of hens was fed a diet with complete feed mixtures with 0.3 mg.kg-1 of clove essential oil. The second group of hens was fed a diet with complete feed mixtures with 0.6 mg.kg-1 of clove oil and the third group of hens was fed a diet with complete feed mixtures with 1 mg.kg-1 of clove oil. Egg production, egg weight (g, specific egg weight, albumen weight (g, albumen index, Haugh Units (HU, yolk weight (g, yolk index, yolk color (HLR were studied. The results show that the addition of clove oil, especially in the group of laying hens with the addition of 1 mg.kg-1 clove oil had no significantly different (P>0.05 to the egg production (the order of the groups: 90.3; 91.8; 91.3; 92.6 %. In egg weight were found no significant differences between groups. The addition of 1 mg.kg-1 clove oil had significant (P>0.05 influenced the albumen index and the addition of 0.6 mg.kg-1 and 1 mg.kg-1 clove oil had significant (P>0.05 influenced Haugh units. In the control group was found not significant (P>0.05 different in yolk weight compared with other groups. In the other parameters of egg quality (albumen weight, yolk index, yolk colour with the addition of clove oil were found no significant differences between groups.

  11. 405 Nigerian Indigenous vs Exotic Hens: the Correlation Factor in ...

    African Journals Online (AJOL)

    FIRST LADY

    2011-01-18

    Jan 18, 2011 ... The weights of the birds were taken at weekly intervals ... Shell Percent (%) was expressed as a percentage of the egg weight and recorded as .... of Nigerian indigenous guinea fowl as influenced by egg size and hatch weight. Nig. J. Anim. Prod. 21 : 59 – 65. Benoff, F.H. and Renden, J.A. (1983). Divergent ...

  12. 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.

  13. The use of distillers dried grains plus solubles as a feed ingredient on air emissions and performance from laying hens.

    Science.gov (United States)

    Wu-Haan, W; Powers, W; Angel, R; Applegate, T J

    2010-07-01

    The objectives of the current study were to evaluate the effect of feeding diets containing 0, 10, or 20% distillers dried grains plus solubles (DDGS) to laying hens (21 to 26 wk of age) on emissions of NH3 and H2S. Hy-Line W-36 hens (n = 640) were allocated randomly to 8 environmental rooms for a 5-wk period (hens in 3 rooms were offered the 10% and 20% DDGS diets each; hens in 2 rooms were offered the 0% DDGS diet). Diets were formulated to contain similar CP levels (18.3%), nonphytate P (0.46%), and Ca (4.2%). On an analyzed basis, the 0, 10, and 20% DDGS diets contained 0.22, 0.27, and 0.42% S. Egg weight (50.9 g), egg production (85%), and feed intake (87.9 g/hen per d) were unaffected by diet (P > 0.05) over the study period. Daily NH3 emissions from hens fed diets containing 0, 10, and 20% DDGS were 105.4, 91.7, and 80.2 mg/g of N consumed, respectively (P hens fed commercial diets containing 0, 10, and 20% DDGS were 2.6, 2.4, and 1.1 mg/g of S consumed, respectively. Overall, feeding 21- to 26-wk-old laying hens diets containing 20% DDGS decreased daily NH3 emissions by 24% and H2S emissions by 58%. Each hen emitted approximately 280 mg of NH3 and 0.5 mg of H2S daily when fed a control diet containing 18% CP and 0.2% S. The results of this study demonstrate that 20% DDGS derived from ethanol production can be fed to laying hens, resulting in lower emissions of NH3 and H2S with no apparent adverse effects on hen performance.

  14. 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.

  15. 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.

  16. Extensive behavioural divergence following colonisation of the freshwater environment in threespine sticklebacks.

    Directory of Open Access Journals (Sweden)

    Carole Di-Poi

    Full Text Available Colonisation of novel environments means facing new ecological challenges often resulting in the evolution of striking divergence in phenotypes. However, little is known about behavioural divergence following colonisation, despite the predicted importance of the role of behavioural phenotype-environment associations in adaptive divergence. We studied the threespine stickleback (Gasterosteus aculeatus, a model system for postglacial colonisation of freshwater habitats largely differing in ecological conditions from the ones faced by the descendants of the marine ancestor. We found that common-environment reared freshwater juveniles were less social, more active and more aggressive than their marine counterparts. This behavioural divergence could represent the result of natural selection that acted on individuals following freshwater colonisation, with predation as a key selection agent. Alternatively, the behavioural profile of freshwater juveniles could represent the characteristics of individuals that preferentially invaded freshwater after the glacial retreat, drawn from the standing variation present in the marine population.

  17. Genetic divergence of common bean cultivars.

    Science.gov (United States)

    Veloso, J S; Silva, W; Pinheiro, L R; Dos Santos, J B; Fonseca, N S; Euzebio, M P

    2015-09-22

    The aim of this study was to evaluate genetic divergence in the 'Carioca' (beige with brown stripes) common bean cultivar used by different institutions and in 16 other common bean cultivars used in the Rede Cooperativa de Pesquisa de Feijão (Cooperative Network of Common Bean Research), by using simple sequence repeats associated with agronomic traits that are highly distributed in the common bean genome. We evaluated 22 polymorphic loci using bulks containing DNA from 30 plants. There was genetic divergence among the Carioca cultivar provided by the institutions. Nevertheless, there was lower divergence among them than among the other cultivars. The cultivar used by Instituto Agronômico do Paraná was the most divergent in relation to the Carioca samples. The least divergence was observed among the samples used by Universidade Federal de Lavras and by Embrapa Arroz e Feijão. Of all the cultivars, 'CNFP 10104' and 'BRSMG Realce' showed the greatest dissimilarity. The cultivars were separated in two groups of greatest similarity using the Structure software. Genetic variation among cultivars was greater than the variation within or between the groups formed. This fact, together with the high estimate of heterozygosity observed and the genetic divergence of the samples of the Carioca cultivar in relation to the original provided by Instituto Agronômico de Campinas, indicates a mixture of cultivars. The high divergence among cultivars provides potential for the utilization of this genetic variability in plant breeding.

  18. 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.

  19. 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

  20. 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

  1. 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...

  2. The estimation of genetic divergence

    Science.gov (United States)

    Holmquist, R.; Conroy, T.

    1981-01-01

    Consideration is given to the criticism of Nei and Tateno (1978) of the REH (random evolutionary hits) theory of genetic divergence in nucleic acids and proteins, and to their proposed alternative estimator of total fixed mutations designated X2. It is argued that the assumption of nonuniform amino acid or nucleotide substitution will necessarily increase REH estimates relative to those made for a model where each locus has an equal likelihood of fixing mutations, thus the resulting value will not be an overestimation. The relative values of X2 and measures calculated on the basis of the PAM and REH theories for the number of nucleotide substitutions necessary to explain a given number of observed amino acid differences between two homologous proteins are compared, and the smaller values of X2 are attributed to (1) a mathematical model based on the incorrect assumption that an entire structural gene is free to fix mutations and (2) the assumptions of different numbers of variable codons for the X2 and REH calculations. Results of a repeat of the computer simulations of Nei and Tateno are presented which, in contrast to the original results, confirm the REH theory. It is pointed out that while a negative correlation is observed between estimations of the fixation intensity per varion and the number of varions for a given pair of sequences, the correlation between the two fixation intensities and varion numbers of two different pairs of sequences need not be negative. Finally, REH theory is used to resolve a paradox concerning the high rate of covarion turnover and the nature of general function sites as permanent covarions.

  3. Verbal and visual divergent thinking in aging.

    Science.gov (United States)

    Palmiero, Massimiliano; Nori, Raffaella; Piccardi, Laura

    2017-04-01

    According to the peak and decline model divergent thinking declines at a specific age (in or after middle age). However, if divergent thinking declines steadily in aging still has to be clarified. In order to explore the age-related changes in verbal and visual divergent thinking, in the present study a sample of 159 participants was divided in five age groups: young adults (18-35 years), middle-aged adults (36-55), young old (56-74), old (75-85) and the oldest-old (86-98). Two divergent thinking tasks were administered: the alternative uses for cardboard boxes, aimed at assessing verbal ideational fluency, flexibility and originality; the completion drawing task, aimed at assessing visual ideational fluency, flexibility and originality. Results showed that after peaking in the young adult group (20-35 years) all components of verbal and visual divergent thinking stabilized in the middle-aged adult group (36-55 years) and then started declining in the young old group (56-75). Interestingly, all components were found to be preserved after declining. Yet, verbal and visual divergent thinking were found at the same extent across age groups, with the exception of visual ideational fluency, that was higher in the young old group, the old group and the oldest-old group than verbal ideational fluency. These results support the idea that divergent thinking does not decline steadily in the elderly. Given that older people can preserve to some extent verbal and visual divergent thinking, these findings have important implications for active aging, that is, divergent thinking might be fostered in aging in order to prevent the cognitive decline.

  4. Adding value to the meat of spent laying hens manufacturing sausages with a healthy appeal

    Directory of Open Access Journals (Sweden)

    KMR de Souza

    2011-03-01

    Full Text Available The aim of this study was to evaluate the viability of the use of spent laying hens' meat in the manufacturing of mortadella-type sausages with healthy appeal by using vegetable oil instead of animal fat. 120 Hy-line® layer hens were distributed in a completely randomized design into two treatments of six replicates with ten birds each. The treatments were birds from light Hy-line® W36 and semi-heavy Hy-line® Brown lines. Cold carcass, wing, breast and leg fillets yields were determined. Dry matter, protein, and lipid contents were determined in breast and leg fillets. The breast and legg fillets of three replicates per treatment were used to manufacture mortadella. After processing, sausages were evaluated for proximal composition, objective color, microbiological parameters, fatty acid profile and sensory acceptance. The meat of light and semi-heavy spent hens presented good yield and composition, allowing it to be used as raw material for the manufacture of processed products. Mortadellas were safe from microbiological point of view, and those made with semi-heavy hens fillets were redder and better accepted by consumers. Values for all sensory attributes were evaluated over score 5 (neither liked nor disliked. Both products presented high polyunsaturated fatty acid contents and good polyunsaturated to saturated fatty acid ratio. The excellent potential for the use of meat from spent layer hens of both varieties in the manufacturing of healthier mortadella-type sausage was demonstrated.

  5. Digestible threonine to lysine ratio in diets for laying hens aged 24-40 weeks

    Directory of Open Access Journals (Sweden)

    Tatiana Cristina da Rocha

    2013-12-01

    Full Text Available Two-hundred sixteen white laying hens were used to assess the ideal ratio of digestible threonine:lysine in diets for laying hens at 24 to 40 weeks of age. Birds were assigned to a randomized block design, with six treatments, six replicates per treatment and six birds per experimental unit. The cage was used as the blocking criterion. Experimental diets contained different digestible threonine:digestible lysine ratios (65, 70, 75, 80, 85 and 90% with 142 g/kg of crude protein. Experimental diets were formulated to be isonitrogenous and isocaloric with different contents of L-glutamic acid. Feed intake (g/hen/d, egg production (%, egg weight (g, egg mass (g/hen/d, feed conversion ratio (kg/dozen and kg/kg egg, eggshell weight (g, albumen weight (g, yolk weight (g and body weight gain (g were assessed. The maximum egg production was observed at 78% digestible threonine:digestible lysine ratio, while the best values of feed conversion ratio (kg/dozen egg and feed conversion ratio (kg/kg of egg were observed at 77.6% and 75%, respectively. Feed intake, egg mass and egg contents (yolk, albumen and eggshell were not affected by treatments. The estimated digestible threonine:digestible lysine ratio of Hy-Line W36 laying hens at 24 to 40 weeks of age is 78%, corresponding to 5.70 g/kg of dietary digestible threonine.

  6. An integrated analysis of social stress in laying hens: The interaction between physiology, behaviour, and hierarchy.

    Science.gov (United States)

    Carvalho, Renata Rezende; Palme, Rupert; da Silva Vasconcellos, Angélica

    2018-04-01

    Livestock is the category of animals that suffers the most severe welfare problems. Among these, physical, physiological, and behavioural distress caused by artificial grouping are some of the challenges faced by these animals. Groups whose members are frequently changed have been reported as socially unstable, which could jeopardise the welfare of animals. Here, we assessed the effect of social instability on aggression, stress, and productivity in groups of laying hens (Gallus gallus domesticus). We studied 36 females, distributed into three stable groups (without group membership change) and three unstable groups (where the dominant member was rotated every week) over the course of 10 weeks. We evaluated the frequency of agonistic interactions, glucocorticoid metabolites (GCM) concentrations, and egg production. In both treatments, dominant hens produced more eggs compared to intermediate and subordinates, and intermediate hens had the highest GCM concentrations. Socially unstable groups had lower productivity and higher frequencies of agonistic interactions than stable groups. Social instability also affected GCM of the animals: in stable groups, subordinate hens had higher concentrations than dominants; in unstable groups, this pattern was reversed. Our results point to a social destabilisation in groups whose members were alternated, and suggest the welfare of individuals in unstable groups was compromised. Our results pointed to a complex relationship between hierarchy, productivity, physiological stress and aggression in laying hens, and have implications for their husbandry and management and, consequently, for their welfare levels. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. 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.

  8. 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.

  9. Effect of lipopolysaccharide on sickness behaviour in hens kept in cage and free range environments.

    Science.gov (United States)

    Gregory, N G; Payne, S R; Devine, C D; Cook, C J

    2009-08-01

    The aim of this study was to assess whether environmental enrichment and environmental conditions can influence the expression of sickness behaviour. The behaviour in response to injection of lipopolysaccharide or saline was examined in a total of 96 62-weeks old hatchmate hens kept in a free range or cage environment. There were eight experimental treatments, each with 12 birds. Half the birds were sourced from a commercial cage layer unit (C/-) and half from a commercial free range unit (FR/-). After intraperitoneal injection with either lipopolysaccharide or saline (as a control), the hens were placed in either a cage (-/C) or free range (-/FR) environment. Lipopolysaccharide caused greater suppression of activity in free range (FR/FR) than in caged hens, including less walking (53% reduction), roosting (-86%) and preening (-60%) (pfree range, nor in free range birds introduced to cages, suggesting that both the presence of and the familiarity with an environment affected sickness behaviour patterns. Increased sleeping was the most consistent response (+147%; pfree range layer hens can express a greater range of sickness behaviours than caged hens, and this may make it more difficult to recognise disease expression in the caged environment.

  10. Diagnostic utility of egg yolk for the detection of avian metapneumovirus antibodies in laying hens.

    Science.gov (United States)

    Choi, Kang-Seuk; Lee, Eun-Kyoung; Jeon, Woo-Jin; Park, Mi-Ja; Yoo, Yae-Na; Kwon, Jun-Hun

    2010-12-01

    Surveillance and diagnosis of avian metapneumovirus (AMPV) infection typically involve measurement of serum antibodies. In the current study, eggs instead of serum samples were used for the detection of AMPV antibodies in egg-laying chicken hens by enzyme-linked immunosorbent assay (ELISA). AMPV-free commercial layer hens were experimentally challenged with AMPV strain SC1509 through intravenous or oculonasal administration. Antibody levels were determined by ELISA. AMPV antibodies were detected in egg yolks from challenged hens by 7 days postinoculation (dpi), with the peak titer at 16 dpi. Antibody levels in eggs laid at 28 dpi correlated well (r = 0.93) with sera taken 28 dpi from the same hens. In a field trial of the yolk ELISA, six broiler breeder farms were surveyed, and all tested positive for AMPV antibodies in hen eggs, although positivity varied from farm to farm. Abnormal discolored eggs collected from outbreak farms had significantly higher titers of AMPV yolk antibodies than normal eggs from the same farm, unlike clinically healthy farms, where normal and abnormal eggs had similar antibody titers. These results indicate that diagnosis of AMPV infection by yolk ELISA to detect anti-AMPV antibodies may be a suitable alternative to serologic testing.

  11. Performance of Commercial Laying Hen Submitted to Different Debeaking Methods

    Directory of Open Access Journals (Sweden)

    CH Oka

    Full Text Available ABSTRACT Among the several factors required in breeding laying hens, debeaking is a factor that interferes with batch performance and affects animal welfare. Thus, the objective of this study was to evaluate three different debeaking procedures and to verify the best technique to be used. For this, the performance of the birds, the incidence of cannibalism, and in rearing phase, the quality of the eggs were evaluated. Dekalb White birds were distributed in a completely randomized design with three treatments, T1 (infrared radiation debeaking T2 (hot blade debeaking and T3 (V debeaking.The data was submitted to Analysis of Variance and compared by Tukey’s test (95%, using statistical software R. The frequencies of mortality and cannibalism were submitted to the Chi-Square test (Software R. It was observed that mortality was lower with IR debeaking in the breeding phase. Already in the rearing phase, the mortality was similar between the debeaking techniques and the cannibalism was null. The final mean weight (g, mean weight gain (g and average daily weight gain in the rearing and egg quality variables were higher for V debeaking when compared to other techniques. It is concluded that V-debeaking provides better bird performance, resistance and shell thickness when compared to the infrared radiations and hot blade debeaking, in addition to subjecting the birds to less stress.

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

    NARCIS (Netherlands)

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

    2017-01-01

    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

  13. Influence of Dermanyssus gallinae and Ascaridia galli infections on behaviour and health of laying hens (Gallus gallus domesticus)

    DEFF Research Database (Denmark)

    Kilpinen, O.; Roepstorff, Allan Knud; Permin, A.

    2005-01-01

    gain, anaemia and even death of some of the hens. Behavioural changes were also observed, as the mite-infected hens showed higher self-grooming and head scratching both during the day and night. 4. A. galli resulted in a lower weight gain but no significant changes were seen in blood variables...

  14. Changes of blood parameters associated with bone remodeling following experimentally induced fatty liver disorder in laying hens

    Science.gov (United States)

    Studies have demonstrated that obesity and osteoporosis are two linked disorders in humans. This study examined if excessive lipid consumption affects bone metabolism in laying hens. One hundred 63-week-old laying hens were randomly divided into two treatments, i.e., fed with a regular diet (control...

  15. 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

  16. 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

  17. Genetic and phenotypic correlations between feather pecking and open-field reponse in laying hens at two different ages

    NARCIS (Netherlands)

    Rodenburg, T.B.; Buitenhuis, A.J.; Ask, B.; Uitdehaag, K.A.; Koene, P.; Poel, van der J.J.; Arendonk, van J.A.M.; Bovenhuis, H.

    2004-01-01

    The object of this research was to study the relationship between feather pecking and open-field activity in laying hens at two different ages. A population of 550 birds of a laying hen cross was subjected to an open-field test at 5 and 29 weeks of age and to a social feather pecking test at 6 and

  18. 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...

  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. Complete Genome Sequence of Gallibacterium anatis Strain UMN179, Isolated from a Laying Hen with Peritonitis ▿

    OpenAIRE

    Johnson, Timothy J.; Fernandez-Alarcon, Claudia; Bojesen, Anders Miki; Nolan, Lisa K.; Trampel, Darrell W.; Seemann, Torsten

    2011-01-01

    Gallibacterium anatis is a member of the normal flora of avian hosts and an important causative agent of peritonitis and salpingitis in laying hens. Here we report the availability of the first completed G. anatis genome sequence of strain UMN179, isolated from an Iowa laying hen with peritonitis.

  1. Complete Genome Sequence of Gallibacterium anatis Strain UMN179, Isolated from a Laying Hen with Peritonitis ▿

    Science.gov (United States)

    Johnson, Timothy J.; Fernandez-Alarcon, Claudia; Bojesen, Anders Miki; Nolan, Lisa K.; Trampel, Darrell W.; Seemann, Torsten

    2011-01-01

    Gallibacterium anatis is a member of the normal flora of avian hosts and an important causative agent of peritonitis and salpingitis in laying hens. Here we report the availability of the first completed G. anatis genome sequence of strain UMN179, isolated from an Iowa laying hen with peritonitis. PMID:21602325

  2. 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

  3. Two New Measures of Fuzzy Divergence and Their Properties

    Directory of Open Access Journals (Sweden)

    Om Parkash

    2006-06-01

    Full Text Available Several measures of directed divergence and their corresponding measures of fuzzy divergence are available in the exiting literature. Two new measures of fuzzy divergence have been developed and their desirable properties have been discussed.

  4. Effect of Free-range Rearing on Meat Composition, Physical Properties and Sensory Evaluation in Taiwan Game Hens

    Directory of Open Access Journals (Sweden)

    Cheng-Yung Lin

    2014-06-01

    Full Text Available Experiments were conducted to evaluate the effect of an outdoor-grazed raising model on meat composition, physical properties and sensory attributes of Taiwan game hens. Six hundred 1-d old female chicks were raised on a floor for 8 weeks. On day 57, 600 healthy birds, with similar body weight, were selected and randomly assigned to three treatment groups (cage, floor-pen and free-range. The results showed that different feeding models had no effect on drip loss, cooking loss, moisture, crude protein, crude fat, crude ash, zinc and calorie contents in breast meat and moisture content in thigh meat. The free-range group had the lowest fat content in both breast and thigh meat, and the lowest calorie content in thigh meat. The firmness and toughness in both thigh and breast of the free-range group were the highest values (p<0.05. The crude protein, total collagen, zinc and iron contents in thigh meat and total collagen content in breast meat of the free-range group were significantly higher than those of the cage-feeding group (p<0.05. The meat sensory scores of flavor, chewiness and overall acceptability of both thigh and breast meat of the free-range group were significantly (p<0.05 better than those of the other two groups. Moreover, the current findings also indicate that the Taiwan game hens of the free-range feeding model displayed well-received carcass traits and meat quality, with higher scores for flavor, chewiness and overall acceptability for greater sensory satisfaction in both breast and thigh meat. In addition, the thigh meat contained high protein and total collage but low fat, offering a healthier diet choice.

  5. 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.

  6. Treatment of divergent expansions in scattering theory

    International Nuclear Information System (INIS)

    Gersten, A.; Malin, S.

    1978-01-01

    One of the biggest obstacles in applying quantum field theory to realistic scattering problems are the divergencies of pertubation expansions for large coupling constants and the divergencies of partial wave expansions for massless particles exchanges. There exist, however, methods of summation of the divergent expansions which can lead to significant application in physics. In this paper we treat the problem of summing such expansions using three methods: (i) a generalization of the Pade approximation to the multivariable case. The suggested definition is unique and preserves unitarity. (ii) The summation of divergent partial waves for arbitrary spins. (iii) A successful application of a series inversion to the 3 P 1 nucleon-nucleon phase shift up to 200 MeV. (orig./WL) [de

  7. Divergence and convergence in nutrition science

    NARCIS (Netherlands)

    Penders, Bart; Spruit, Shannon L.; Sikkema, Jan; Maat, Jan; Schuurbiers, Daan

    2015-01-01

    Nutrigenomics diverged from mainstream nutrition science, ideologically, instrumentally and culturally, due to the establishment of a protective niche. That protection is fading. This article chronicles a case in which convergence between nutrigenomics and nutrition science is pursued. Here we

  8. Sympatric and allopatric divergence of MHC genes in threespine stickleback.

    Directory of Open Access Journals (Sweden)

    Blake Matthews

    2010-06-01

    Full Text Available Parasites can strongly affect the evolution of their hosts, but their effects on host diversification are less clear. In theory, contrasting parasite communities in different foraging habitats could generate divergent selection on hosts and promote ecological speciation. Immune systems are costly to maintain, adaptable, and an important component of individual fitness. As a result, immune system genes, such as those of the Major Histocompatibility Complex (MHC, can change rapidly in response to parasite-mediated selection. In threespine stickleback (Gasterosteus aculeatus, as well as in other vertebrates, MHC genes have been linked with female mating preference, suggesting that divergent selection acting on MHC genes might influence speciation. Here, we examined genetic variation at MHC Class II loci of sticklebacks from two lakes with a limnetic and benthic species pair, and two lakes with a single species. In both lakes with species pairs, limnetics and benthics differed in their composition of MHC alleles, and limnetics had fewer MHC alleles per individual than benthics. Similar to the limnetics, the allopatric population with a pelagic phenotype had few MHC alleles per individual, suggesting a correlation between MHC genotype and foraging habitat. Using a simulation model we show that the diversity and composition of MHC alleles in a sympatric species pair depends on the amount of assortative mating and on the strength of parasite-mediated selection in adjacent foraging habitats. Our results indicate parallel divergence in the number of MHC alleles between sympatric stickleback species, possibly resulting from the contrasting parasite communities in littoral and pelagic habitats of lakes.

  9. Effect of Olive Leaf ( Powder on Laying Hens Performance, Egg Quality and Egg Yolk Cholesterol Levels

    Directory of Open Access Journals (Sweden)

    H. Cayan

    2015-04-01

    Full Text Available This experiment was conducted to measure the effects of olive leaf powder on performance, egg yield, egg quality and yolk cholesterol level of laying hens. A total of 120 Lohmann Brown laying hens of 22 weeks old were used in this experiment. The birds were fed on standard layer diets containing 0, 1%, 2%, or 3% olive leaf powder for 8 weeks. Egg weight and yield were recorded daily; feed intake weekly; egg quality and cholesterol content at the end of the trial. Olive leaf powder had no effect on feed intake, egg weight, egg yield and feed conversion ratio (p>0.05 while olive leaf powder increased final body weight of hens (p0.05. To conclude, olive leaf powder can be used for reducing egg yolk cholesterol content and egg yolk coloring agent in layer diets.

  10. 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...

  11. 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.

  12. Decoding divergent series in nonparaxial optics.

    Science.gov (United States)

    Borghi, Riccardo; Gori, Franco; Guattari, Giorgio; Santarsiero, Massimo

    2011-03-15

    A theoretical analysis aimed at investigating the divergent character of perturbative series involved in the study of free-space nonparaxial propagation of vectorial optical beams is proposed. Our analysis predicts a factorial divergence for such series and provides a theoretical framework within which the results of recently published numerical experiments concerning nonparaxial propagation of vectorial Gaussian beams find a meaningful interpretation in terms of the decoding operated on such series by the Weniger transformation.

  13. 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.

  14. Pulse radiolysis studies of intramolecular electron transfer in model peptides and proteins. 7. Trp -> TyrO radical transformation in hen egg-white lysozyme. Effects of pH, temperature, Trp62 oxidation and inhibitor binding

    DEFF Research Database (Denmark)

    Bobrowski, K.; Holcman, J.; Poznanski, J.

    1997-01-01

    Intramolecular long-range electron transfer (LRET) in hen egg-white lysozyme (HEWL) accompanying Trp --> TyrO radical transformation was investigated in aqueous solution by pulse radiolysis as a function of pH (5.2-7.4) and temperature (283-328K). The reaction was induced by highly selective...... below its denaturation temperature. Selective oxidation by ozone of the Trp62 indole side-chain in HEWL to N'-formylkynurenine (NFKyn62-HEWL) caused a large drop in the initial yield of Trp(.) radicals, G(Trp(.))(i). This was accompanied by a relatively small decrease in k(5) but selective oxidation...

  15. Collinearity, convergence and cancelling infrared divergences

    International Nuclear Information System (INIS)

    Lavelle, Martin; McMullan, David

    2006-01-01

    The Lee-Nauenberg theorem is a fundamental quantum mechanical result which provides the standard theoretical response to the problem of collinear and infrared divergences. Its argument, that the divergences due to massless charged particles can be removed by summing over degenerate states, has been successfully applied to systems with final state degeneracies such as LEP processes. If there are massless particles in both the initial and final states, as will be the case at the LHC, the theorem requires the incorporation of disconnected diagrams which produce connected interference effects at the level of the cross-section. However, this aspect of the theory has never been fully tested in the calculation of a cross-section. We show through explicit examples that in such cases the theorem introduces a divergent series of diagrams and hence fails to cancel the infrared divergences. It is also demonstrated that the widespread practice of treating soft infrared divergences by the Bloch-Nordsieck method and handling collinear divergences by the Lee-Nauenberg method is not consistent in such cases

  16. 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.

  17. 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.

  18. Comparison of amino acid digestibility of feed ingredients in broilers, laying hens and caecectomised roosters.

    Science.gov (United States)

    Adedokun, S A; Utterback, P; Parsons, C M; Adeola, O; Lilburn, M S; Applegate, T J

    2009-05-01

    1. This study determined the effect of bird type (broilers, laying hens, or caecectomised roosters) on amino acid digestibility of feedstuffs from 5 plant sources and one animal source. 2. The standardised amino acid digestibility (SAAD) were obtained by correcting apparent ileal amino acid digestibility (AIAAD) values for basal ileal endogenous amino acid (EAA) flow obtained by feeding a N-free diet (NFD) to broilers and laying hens or from fasted EAA flow from caecectomised roosters. 3. The apparent total amino acid (TAA) digestibilities did not differ between broilers and roosters for three of the 6 feed ingredients. 4. Broilers had higher apparent total amino acid (TAA) digestibility than laying hens and roosters when fed on the maize diet (canola meal, maize, and soybean meal). 5. The apparent TAA digestibilities were similar across bird types for the dark distillers' dried grain with solubles, but the apparent lysine digestibility was much lower in the caecectomised roosters (15%) than the broilers (49%) and laying hens (43%). 6. The standardised TAA digestibility values in roosters were higher than in broilers for three of the 6 feed ingredients (canola meal, soybean meal, or meat and bone meal). 7. There were no differences between broilers and roosters, however, in the standardised TAA digestibility values for maize, dark and light DDGS. 8. The standardised TAA digestibility values for laying hens were lower for maize, higher for meat and bone meal, but no different for the remaining ingredients when compared with broilers. 9. The results from this study showed that both the apparent and standardised amino acid digestibility values in caecectomised roosters, laying hens, and broilers ingredients are similar for some, but not all, feed ingredients. 10. Nutritionists should, therefore, be cautious about using digestibility coefficients obtained by different methodologies as values may differ.

  19. Comparison of the characteristics in hen and quail corneas as experimental models of refractive surgery.

    Science.gov (United States)

    Gonçalves, G C; Pérez-Merino, P; Martínez-García, M C; Barcía, A; Merayo-Loves, J

    2016-07-01

    To compare the histological, morphological and the biophysical measurements between hen and quail corneas, in order to determine which of them were better suited for use as an animal model for research into corneal refractive surgery. A study was performed using the biophysical measurements of the cornea (curvature, thickness, refraction, and axial length) of 20 animals (10 hens and 10 quails). The corneas were then prepared for histological analysis under microscopy light. The analysis showed that both groups have the same number of corneal layers as the human cornea and with an evident Bowman's layer. The thickness of the hen cornea and axial length of the eye, 225.3±18.4μm and 12.8±0.25mm, respectively, were larger than that of the quail (Phen central cornea, 3.65±0.08mm, was greater than that for the quail (Ppower of each cornea was similar. The proportion of total corneal thickness of the hen stroma, 82.6%, was more similar to that of the human than was the quail stroma, 72.5%. Within the hen stroma, the density of keratocytes, 8.57±1.49 per 5,000μm(2), was about half that in the quail stroma (Phen cornea, the stromal thickness and proportional similarity of the corneal layers with human cornea, the hen maybe better than the quail as an alternative species suitable for use in studies of corneal refractive surgery. Copyright © 2016 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.

  20. Relationships between range access as monitored by radio frequency identification technology, fearfulness, and plumage damage in free-range laying hens.

    Science.gov (United States)

    Hartcher, K M; Hickey, K A; Hemsworth, P H; Cronin, G M; Wilkinson, S J; Singh, M

    2016-05-01

    Severe feather-pecking (SFP), a particularly injurious behaviour in laying hens (Gallus gallus domesticus), is thought to be negatively correlated with range use in free-range systems. In turn, range use is thought to be inversely associated with fearfulness, where fearful birds may be less likely to venture outside. However, very few experiments have investigated the proposed association between range use and fearfulness. This experiment investigated associations between range use (time spent outside), fearfulness, plumage damage, and BW. Two pens of 50 ISA Brown laying hens (n=100) were fitted with radio frequency identification (RFID) transponders (contained within silicone leg rings) at 26 weeks of age. Data were then collected over 13 days. A total of 95% of birds accessed the outdoor run more than once per day. Birds spent an average duration of 6.1 h outside each day over 11 visits per bird per day (51.5 min per visit). The top 15 and bottom 15 range users (n=30), as determined by the total time spent on the range over 13 days, were selected for study. These birds were tonic immobility (TI) tested at the end of the trial and were feather-scored and weighed after TI testing. Birds with longer TI durations spent less time outside (P=0.01). Plumage damage was not associated with range use (P=0.68). The small group sizes used in this experiment may have been conducive to the high numbers of birds utilising the outdoor range area. The RFID technology collected a large amount of data on range access in the tagged birds, and provides a potential means for quantitatively assessing range access in laying hens. The present findings indicate a negative association between fearfulness and range use. However, the proposed negative association between plumage damage and range use was not supported. The relationships between range use, fearfulness, and SFP warrant further research.

  1. Divergent Ah Receptor Ligand Selectivity during Hominin Evolution.

    Science.gov (United States)

    Hubbard, Troy D; Murray, Iain A; Bisson, William H; Sullivan, Alexis P; Sebastian, Aswathy; Perry, George H; Jablonski, Nina G; Perdew, Gary H

    2016-10-01

    We have identified a fixed nonsynonymous sequence difference between humans (Val381; derived variant) and Neandertals (Ala381; ancestral variant) in the ligand-binding domain of the aryl hydrocarbon receptor (AHR) gene. In an exome sequence analysis of four Neandertal and Denisovan individuals compared with nine modern humans, there are only 90 total nucleotide sites genome-wide for which archaic hominins are fixed for the ancestral nonsynonymous variant and the modern humans are fixed for the derived variant. Of those sites, only 27, including Val381 in the AHR, also have no reported variability in the human dbSNP database, further suggesting that this highly conserved functional variant is a rare event. Functional analysis of the amino acid variant Ala381 within the AHR carried by Neandertals and nonhuman primates indicate enhanced polycyclic aromatic hydrocarbon (PAH) binding, DNA binding capacity, and AHR mediated transcriptional activity compared with the human AHR. Also relative to human AHR, the Neandertal AHR exhibited 150-1000 times greater sensitivity to induction of Cyp1a1 and Cyp1b1 expression by PAHs (e.g., benzo(a)pyrene). The resulting CYP1A1/CYP1B1 enzymes are responsible for PAH first pass metabolism, which can result in the generation of toxic intermediates and perhaps AHR-associated toxicities. In contrast, the human AHR retains the ancestral sensitivity observed in primates to nontoxic endogenous AHR ligands (e.g., indole, indoxyl sulfate). Our findings reveal that a functionally significant change in the AHR occurred uniquely in humans, relative to other primates, that would attenuate the response to many environmental pollutants, including chemicals present in smoke from fire use during cooking. © The Author 2016. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  2. Metabolic rate and thyroid activity of hens in relation to the state of feathering.

    Science.gov (United States)

    Pietras, M

    1981-01-01

    Heat production, rectal temperature and thyroid activity were determined in NH X Lg hens that were 40 and 80% defeathered. Within individual groups there was a significant increase in heat production only in hens that were 80% defeathered. In comparison with the control group, defeathered chickens had higher metabolic rates during each examined period. During the third week of the experiment there was a temporary drop in the rectal temperature of the experimental birds. After nine weeks chicken with the greatest degree of defeathering had the highest thyroid weight and the highest levels of thyroxin in the blood plasma.

  3. Effects of initiating anaerobic digestion of layer-hen poultry dung at sub-atmospheric pressure

    OpenAIRE

    Ngumah, Chima C.; Ogbulie, Jude N.; Orji, Justina C.; Amadi, Ekperechi S.

    2013-01-01

    This study investigated the effects of initiating anaerobic digestion (AD) of dry layer-hen poultry dung at the sub-atmospheric pressure of -30 cmHg on biodegradation, biogasification, and biomethanation. The setup was performed as a batch process at an average ambient temperature of 29±2 ºC and a retention time of 15 days. Comparisons were made with two other experiments which were both begun at ambient atmospheric pressure; one was inoculated with digestate from a previous layer-hen dung AD...

  4. 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

  5. Supplementation of extract of Lafoensia pacari in the diet of semi heavy laying hens

    OpenAIRE

    Moreira, Janaina da Silva; Stringhini, José Henrique; Conceição, Edemilson Cardoso da; Arhnold, Emmanuel; Noleto, Raiana Almeida; Carvalho, Fabyola Barros de

    2017-01-01

    ABSTRACT. It was intended to evaluate the supplementation of Lafoensia pacari standardized in tannins extract in the diet of laying hens on the performance, internal and external quality of eggs and metabolism of the feed nutrients. A total of 168 Isa Brown laying hens, aged 24 weeks, with the mean weight of 2.6 kg and the mean posture rate of 87% were used during 4 periods of 28 days each. The treatments consisted of Halquinol performance-enhancing antibiotic, Mannanoligosaccharide (MOS) pre...

  6. Examinations of hens' eggs on residues of Chloramphenicol using a radioimmunoassay

    International Nuclear Information System (INIS)

    Scherk, F.; Agthe, O.

    1986-01-01

    In the Federal Republic of Germany the application of Chloramphenicol to animals used for human food supply is restricted by law. Milk and dairy products as well as hen's eggs and egg products are not allowed to contain more than 1 ppb Chloramphenicol. 18 hens were fed with water treated with Chloramphenicol. The eggs of the treated animals were then analysed by means of radioimmunoassay. The applied radioimmunoassay is suitable for routine analysis to a minimum detection limit of 1 ppb. 378 eggs from the Weser-Ems district were tested for Chloramphenicol. No sample contained Chloramphenicol. (orig.) [de

  7. preservation of irradiated mechanically separated turkey hen meat based Vienna sausages

    International Nuclear Information System (INIS)

    Ben Abderabba, N.

    1996-01-01

    This study evaluates the influence of growing doses of irradiation on the microbiological quality (pathogenic bacteria, faecal contaminants, total germs) and the physical and chemical characteristics (pH, humidity, total free fat materials, chloride and protein) of mechanically separated turkey hen meat. This study also permitted the measuring of the effects of incorporation of mechanical y separated turkey hen meat irradiated at 5 KGy on the microbiological, physical, chemical and structural qualities of Vienna sausages, as manufactured in a private company in Tunis (author)

  8. Possibilities of reducing radiocesium transfer to hen eggs. II. Using bentonite from Polish geological deposits

    International Nuclear Information System (INIS)

    Rachubik, J.; Kowalski, B.

    2000-01-01

    The decontamination effectiveness of bentonite from Polish geological deposits in reducing the radiocesium transfer to hen eggs was examined. The egg white radiocesium concentration was higher than that in egg yolk. The highest decontamination efficacy in all egg components was noticed in animals treated with bentonite from the first day of radionuclide administration. Generally, the radioactivity concentration in hens treated simultaneously with 137CsCl and a cesium binder were lower by 50% than those in the controls. The decontamination efficiency lowered with the delayed bentonite treatment. In Poland bentonite seems to be an alternative to other decontamination agents. (author)

  9. Divergence of iron metabolism in wild Malaysian yeast.

    Science.gov (United States)

    Lee, Hana N; Mostovoy, Yulia; Hsu, Tiffany Y; Chang, Amanda H; Brem, Rachel B

    2013-12-09

    Comparative genomic studies have reported widespread variation in levels of gene expression within and between species. Using these data to infer organism-level trait divergence has proven to be a key challenge in the field. We have used a wild Malaysian population of S. cerevisiae as a test bed in the search to predict and validate trait differences based on observations of regulatory variation. Malaysian yeast, when cultured in standard medium, activated regulatory programs that protect cells from the toxic effects of high iron. Malaysian yeast also showed a hyperactive regulatory response during culture in the presence of excess iron and had a unique growth defect in conditions of high iron. Molecular validation experiments pinpointed the iron metabolism factors AFT1, CCC1, and YAP5 as contributors to these molecular and cellular phenotypes; in genome-scale sequence analyses, a suite of iron toxicity response genes showed evidence for rapid protein evolution in Malaysian yeast. Our findings support a model in which iron metabolism has diverged in Malaysian yeast as a consequence of a change in selective pressure, with Malaysian alleles shifting the dynamic range of iron response to low-iron concentrations and weakening resistance to extreme iron toxicity. By dissecting the iron scarcity specialist behavior of Malaysian yeast, our work highlights the power of expression divergence as a signpost for biologically and evolutionarily relevant variation at the organismal level. Interpreting the phenotypic relevance of gene expression variation is one of the primary challenges of modern genomics.

  10. Increased genetic divergence between two closely related fir species in areas of range overlap

    Science.gov (United States)

    Wang, Jing; Abbott, Richard J; Ingvarsson, Pär K; Liu, Jianquan

    2014-01-01

    Because of introgressive hybridization, closely related species can be more similar to each other in areas of range overlap (parapatry or sympatry) than in areas where they are geographically isolated from each other (allopatry). Here, we report the reverse situation based on nuclear genetic divergence between two fir species, Abies chensiensis and Abies fargesii, in China, at sites where they are parapatric relative to where they are allopatric. We examined genetic divergence across 126 amplified fragment length polymorphism (AFLP) markers in a set of 172 individuals sampled from both allopatric and parapatric populations of the two species. Our analyses demonstrated that AFLP divergence was much greater between the species when comparisons were made between parapatric populations than between allopatric populations. We suggest that selection in parapatry may have largely contributed to this increased divergence. PMID:24772279

  11. Dynamics of hydration in hen egg white lysozyme.

    Science.gov (United States)

    Sterpone, F; Ceccarelli, M; Marchi, M

    2001-08-10

    We investigate the hydration dynamics of a small globular protein, hen egg-white lysozyme. Extensive simulations (two trajectories of 9 ns each) were carried out to identify the time-scales and mechanism of water attachment to this protein. The location of the surface and integral water molecules in lysozyme was also investigated. Three peculiar temporal scales of the hydration dynamics can be discerned: two among these, with sub-nanosecond mean residence time, tau(w), are characteristic of surface hydration water; the slower time-scale (tau(w) approximately 2/3 ns) is associated with buried water molecules in hydrophilic pores and in superficial clefts. The computed tau(w) values in the two independent runs fall in a similar range and are consistent with each other, thus adding extra weight to our result. The tau(w) of surface water obtained from the two independent trajectories is 20 and 24 ps. In both simulations only three water molecules are bound to lysozyme for the entire length of the trajectories, in agreement with nuclear magnetic relaxation dispersion estimates. Locations other than those identified in the protein crystal are found to be possible for these long-residing water molecules. The dynamics of the hydration water molecules observed in our simulations implies that each water molecule visits a multitude of residues during the lifetime of its bound with the protein. The number of residues seen by a single water molecule increases with the time-scale of its residence time and, on average, is equal to one only for the water molecules with shorter residence time. Thus, tau(w) values obtained from inelastic neutron scattering and based on jump-diffusion models are likely not to account for the contribution of water molecules with longer residence time. Copyright 2001 Academic Press.

  12. Utilization of nitrogen-15 from wheat by growing poultry and laying hens

    International Nuclear Information System (INIS)

    Hennig, A.; Gruhn, K.; Jahreis, G.

    1976-01-01

    Nitrogen-15 offered to broiler chickens and laying hens has been tested. The test animals were given wheat (atom % 15 N-excess 20-25%) or 15 N-lysine in balanced rations. The results showed that different feedstuffs are transported selectively through the gastro-intestinal tract. Therefore the atom % 15 N-excess is higher in the contents of the crop, the proventriculus and the gizzard in comparison with the feed. Some hours after feeding the atom % 15 N-excess in the contents of the small intestine is lower than in other parts of the intestinal tract (3 to 12 hours after feeding). As to atom % 15 N, there is a significant correlation between the contents of the small intestine and the gut wall (r=0.99). As the amount of nitrogen in the contents of the small intestine does not change between 3 and 12 hours after feeding, the obvious dilution of 15 N does not allow conclusions to be made regarding the endogenic secretion. In the steady state, 24% of the 15 N of wheat lysine, 12% of the 15 N of wheat histidine and 9% of arginine were excreted in the faeces. Four days after the last feed intake of labelled wheat or lysine we found more 15 N in the carcass than in the total sum of eggs. Four days after the last feeding the albumen showed a higher labelling rate than urine. The 15 N of wheat was differently incorporated into thoracic, leg and heart muscles. We found a different half-life time for the individual muscle protein types in the following order: heart, leg, thoracic. Within the eight-day period no changes were observed in the level of labelling in the thoracic muscle. (author)

  13. Accelerated shelf-life testing of quality loss for a commercial hydrolysed hen egg white powder.

    Science.gov (United States)

    Rao, Qinchun; Rocca-Smith, Jeancarlo R; Schoenfuss, Tonya C; Labuza, Theodore P

    2012-11-15

    In recent years, due to the specific health benefits associated with bioactive peptides and the reduction of protein allergenicity by enzymatic hydrolysis, the utilisation of protein hydrolysates in functional foods and beverages for both protein supplementation and clinical use has significantly increased. However, few studies have explored the moisture-induced effects on food protein hydrolysates, and the resulting changes in the structure and texture of the food matrix as well as the loss in functional properties of bioactive peptides during storage. The main purpose of this study is to determine the influence of water activity (a(w)) on the storage quality of a commercial spray-dried hydrolysed hen egg white powder (HEW). During storage at 45 °C for two months at different a(w)s (0.05-0.79), the selected physicochemical properties of the HEW samples were analysed. Overall, the effect of a(w) on the colour change of HEW at 45 °C for one month was similar to that of HEW after four months at 23 °C due to the presence of a small amount of glucose in HEW. Several structural changes occurred at a(w)s from 0.43 to 0.79 including agglomeration, stickiness and collapse. Kinetic analysis showed a first-order hyperbolic model fit for the change in the L(∗) value, the total colour difference (ΔE(∗)) and the fluorescence intensity (FI). There was a high correlation between colour change and fluorescence, as expected for the Maillard reaction. The reduction in the remaining free amino groups was about 5% at a(w) 0.50 and 6% at a(w) 0.79 after one month storage. In summary, during storage, the Maillard reaction and/or its resulting products could decrease the nutritional value and the quality of HEW. Copyright © 2012 Elsevier Ltd. All rights reserved.

  14. Differential Survival between Visual Environments Supports a Role of Divergent Sensory Drive in Cichlid Fish Speciation.

    Science.gov (United States)

    Maan, Martine E; Seehausen, Ole; Groothuis, Ton G G

    2017-01-01

    Identifying the selective forces that initiate ecological speciation is a major challenge in evolutionary biology. Sensory drive has been implicated in speciation in various taxa, largely based on phenotype-environment correlations and signatures of selection in sensory genes. Here, we present a reciprocal transplant experiment revealing species differences in performance in alternative visual environments, consistent with speciation by divergent sensory drive. The closely related cichlids Pundamilia pundamilia and Pundamilia nyererei inhabit different visual environments in Lake Victoria and show associated differences in visual system properties. Mimicking the two light environments in the laboratory, we find a substantial reduction in survival of both species when reared in the other species' visual environment. This implies that the observed differences in Pundamilia color vision are indeed adaptive and substantiates the implicit assumption in sensory drive speciation models that divergent environmental selection is strong enough to drive divergence in sensory properties.

  15. 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

  16. Kernel and divergence techniques in high energy physics separations

    Science.gov (United States)

    Bouř, Petr; Kůs, Václav; Franc, Jiří

    2017-10-01

    Binary decision trees under the Bayesian decision technique are used for supervised classification of high-dimensional data. We present a great potential of adaptive kernel density estimation as the nested separation method of the supervised binary divergence decision tree. Also, we provide a proof of alternative computing approach for kernel estimates utilizing Fourier transform. Further, we apply our method to Monte Carlo data set from the particle accelerator Tevatron at DØ experiment in Fermilab and provide final top-antitop signal separation results. We have achieved up to 82 % AUC while using the restricted feature selection entering the signal separation procedure.

  17. Effects of energy concentration of the diet on productive performance and egg quality of brown egg-laying hens differing in initial body weight.

    Science.gov (United States)

    Pérez-Bonilla, A; Novoa, S; García, J; Mohiti-Asli, M; Frikha, M; Mateos, G G

    2012-12-01

    The influence of AME(n) concentration of the diet on productive performance and egg quality traits was studied in Hy-Line brown egg-laying hens differing in initial BW from 24 to 59 wk of age. Eight treatments were arranged factorially with 4 diets varying in energy content (2,650, 2,750, 2,850, and 2,950 kcal of AME(n)/kg) and 2 initial BW of the hens (1,733 vs. 1,606 g). Each treatment was replicated 5 times (13 hens per replicate), and all diets had similar nutrient content per unit of energy. No interactions between energy content of the diet and initial BW of the hens were detected for any trait. An increase in energy concentration of the diet increased (linear, P feed conversion ratio per kilogram of eggs (linear, P Feed intake (114.6 vs. 111.1 g/hen per day), AME(n) intake (321 vs. 311 kcal/hen per day), egg weight (64.2 vs. 63.0 g), and egg mass (58.5 vs. 57.0 g) were higher for the heavier than for the lighter hens (P feed conversion ratio per kilogram of eggs and energy efficiency were not affected. Eggs from the heavier hens had a higher proportion of yolk and lower proportion of albumen (P hens. Consequently, the yolk-to-albumen ratio was higher (P hens. It is concluded that brown egg-laying hens respond with increases in egg production and egg mass to increases in AME(n) concentration of the diet up to 2,850 kcal/kg. Heavy hens had higher feed intake and produced heavier eggs and more egg mass than light hens. However, feed and energy efficiency were better for the lighter hens.

  18. Effects of feeding grains naturally contaminated with Fusarium mycotoxins on brain regional neurochemistry of laying hens, turkey poults, and broiler breeder hens.

    Science.gov (United States)

    Yegani, M; Chowdhury, S R; Oinas, N; MacDonald, E J; Smith, T K

    2006-12-01

    Three experiments were conducted to compare the effects of feeding blends of grains naturally contaminated with Fusarium mycotoxins on brain regional neurochemistry of laying hens, turkey poults, and broiler breeder hens. In Experiment 1, thirty-six 45-wk-old laying hens were fed diets including the following for 4 wk: 1) control, 2) contaminated grains, and 3) contaminated grains + 0.2% polymeric glucomannan mycotoxin adsorbent (GMA). Concentrations of brain neurotransmitters and metabolites were analyzed in pons, hypothalamus, and cortex by HPLC with electrochemical detection. Neurotransmitters and the metabolites measured included dopamine, 3,4-dihydroxylphenyacetic acid, homovanillic acid, serotonin [5-hydroxytryptamine (5-HT)], 5-hydroxyindolacetic acid, epinephrine, and norepinephrine. The feeding of contaminated grains significantly increased concentrations of 5-HT and decreased the 5-hydroxyindolacetic acid:5-HT in the pons region in the brain stem. Dietary supplementation with GMA prevented these effects. There was no effect of diet on concentrations of other neurotransmitters or metabolites in the pons, hypothalamus, or cortex. In Experiment 2, thirty-six 1-d-old turkey poults were fed diets including the following for 4 wk: 1) control, 2) contaminated grains, and 3) contaminated grains + 0.2% GMA. Hypothalamic, pons, and cortex neurotransmitter concentrations were not affected by diet. In Experiment 3, forty-two 26-wk-old broiler breeder hens were fed diets including the following for 15 wk: 1) control, 2) contaminated grains, and 3) contaminated grains + 0.2% GMA. There was no effect of diet on neurotransmitter concentrations in the pons, hypothalamus, or cortex. It was concluded that differences in intraspecies effects of these mycotoxins on brain neurotransmitter concentrations might explain the intraspecies differences in the severity of Fusarium mycotoxin-induced reductions in feed intake.

  19. The constancy of gene conservation across divergent bacterial orders

    Directory of Open Access Journals (Sweden)

    Ackermann Martin

    2009-01-01

    Full Text Available Abstract Background Orthologous genes are frequently presumed to perform similar functions. However, outside of model organisms, this is rarely tested. One means of inferring changes in function is if there are changes in the level of gene conservation and selective constraint. Here we compare levels of gene conservation across three bacterial groups to test for changes in gene functionality. Findings The level of gene conservation for different orthologous genes is highly correlated across clades, even for highly divergent groups of bacteria. These correlations do not arise from broad differences in gene functionality (e.g. informational genes vs. metabolic genes, but instead seem to result from very specific differences in gene function. Furthermore, these functional differences appear to be maintained over very long periods of time. Conclusion These results suggest that even over broad time scales, most bacterial genes are under a nearly constant level of purifying selection, and that bacterial evolution is thus dominated by selective and functional stasis.

  20. Effect of dietary inclusion of sugar syrup on production performance, egg quality and blood biochemical parameters in laying hens

    Directory of Open Access Journals (Sweden)

    Ahmed S. Hussein

    2018-03-01

    Full Text Available The effects of dietary inclusion of sugar syrup on quality of egg, cholesterol level, production performance, serum total protein and blood biochemical parameters were evaluated in laying hens. A total of 300 commercial Lohmann LSL hens (30 weeks of age were randomly distributed into 3 dietary treatments which consisted of a normal corn diet containing corn–soy and 2 diets containing 5% and 10% sugar syrup. Each treatment was replicated 5 times (n = 20. Egg production, feed intake, body weight and egg weight of laying hens fed different diets were recorded. The experiment lasted for 20 weeks. The Haugh unit scores of hens fed diets with sugar syrup were significantly increased (P < 0.05 compared with the control treatment. The sugar syrup had no significant effect on liver enzymes, total protein, blood glucose and creatinine in all treatments. The eggs laid by hens fed sugar syrup diets had lower cholesterol level (P < 0.05 compared with those laid by hens fed the control diet. Electrophoresis analysis showed that comparable electrophoretic patterns were noticed between serum proteins of treatment groups. From the results, it can be concluded that sugar syrup diets and corn diets have similar effects on feed intake, body weight, production of eggs and blood biochemical parameters in layer hens, which suggests sugar syrup can be used as an energy source for replacing part of corn in poultry layer diets. Keywords: Cholesterol, Sugar syrup diet, Egg, Egg quality, Protein

  1. An RFID-Based Smart Nest Box: An Experimental Study of Laying Performance and Behavior of Individual Hens

    Directory of Open Access Journals (Sweden)

    Ying-Ren Chien

    2018-03-01

    Full Text Available This study designed a radio-frequency identification (RFID-based Internet of Things (IoT platform to create the core of a smart nest box. At the sensing level, we have deployed RFID-based sensors and egg detection sensors. A low-frequency RFID reader is installed in the bottom of the nest box and a foot ring RFID tag is worn on the leg of individual hens. The RFID-based sensors detect when a hen enters or exits the nest box. The egg-detection sensors are implemented with a resistance strain gauge pressure sensor, which weights the egg in the egg-collection tube. Thus, the smart nest box makes it possible to analyze the laying performance and behavior of individual hens. An evaluative experiment was performed using an enriched cage, a smart nest box, web camera, and monitoring console. The hens were allowed 14 days to become accustomed to the experimental environment before monitoring began. The proposed IoT platform makes it possible to analyze the egg yield of individual hens in real time, thereby enabling the replacement of hens with egg yield below a pre-defined level in order to meet the overall target egg yield rate. The results of this experiment demonstrate the efficacy of the proposed RFID-based smart nest box in monitoring the egg yield and laying behavior of individual hens.

  2. 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.

  3. Properties of classical and quantum Jensen-Shannon divergence

    NARCIS (Netherlands)

    J. Briët (Jop); P. Harremoës (Peter)

    2009-01-01

    htmlabstractJensen-Shannon divergence (JD) is a symmetrized and smoothed version of the most important divergence measure of information theory, Kullback divergence. As opposed to Kullback divergence it determines in a very direct way a metric; indeed, it is the square of a metric. We consider a

  4. Beam Angular Divergence Effects in Ion Implantation

    International Nuclear Information System (INIS)

    Horsky, T. N.; Hahto, S. K.; Bilbrough, D. G.; Jacobson, D. C.; Krull, W. A.; Goldberg, R. D.; Current, M. I.; Hamamoto, N.; Umisedo, S.

    2008-01-01

    An important difference between monomer ion beams and heavy molecular beams is a significant reduction in beam angular divergence and increased on-wafer angular accuracy for molecular beams. This advantage in beam quality stems from a reduction in space-charge effects within the beam. Such improved angular accuracy has been shown to have a significant impact on the quality and yield of transistor devices [1,12]. In this study, B 18 H x + beam current and angular divergence data collected on a hybrid scanned beam line that magnetically scans the beam across the wafer is presented. Angular divergence is kept below 0.5 deg from an effective boron energy of 200 eV to 3000 eV. Under these conditions, the beam current is shown analytically to be limited by space charge below about 1 keV, but by the matching of the beam emittance to the acceptance of the beam line above 1 keV. In addition, results of a beam transport model which includes variable space charge compensation are presented, in which a drift mode B 18 H x + beam is compared to an otherwise identical boron beam after deceleration. Deceleration is shown to introduce significant space-charge blow up resulting in a large on-wafer angular divergence. The divergence effects introduced by wafer charging are also discussed.

  5. Ion divergence in magnetically insulated diodes

    International Nuclear Information System (INIS)

    Slutz, S.A.; Lemke, R.W.; Pointon, T.D.; Desjarlais, M.P.; Johnson, D.J.; Mehlhorn, T.A.; Filuk, A.; Bailey, J.

    1995-01-01

    Magnetically insulated ion diodes are being developed to drive inertial confinement fusion. Ion beam microdivergence must be reduced to achieve the very high beam intensities required to achieve this goal. Three-dimensional particle-in-cell simulations indicate that instability induced fluctuations can produce significant ion divergence during acceleration. These simulations exhibit a fast growing mode early in time, which has been identified as the diocotron instability. The divergence generated by this mode is modest due to the relatively high frequency (>1GHz). Later, a low-frequency low-phase-velocity instability develops. This instability couples effectively to the ions, since the frequency is approximately the reciprocal of the ion transit time, and can generate unacceptably large ion divergences (>30 mrad). Linear stability theory reveals that this mode requires perturbations parallel to the applied magnetic field and is related to the modified two stream instability. Measurements of ion density fluctuations and energy-momentum correlations have confirmed that instabilities develop in ion diodes and contribute to the ion divergence. In addition, spectroscopic measurements indicate that the ions have a significant transverse temperature very close to the emission surface. Passive lithium fluoride (LiF) anodes have larger transverse beam temperatures than laser irradiated active sources. Calculations of source divergence expected from the roughness of LiF surfaces and the possible removal of this layer is presented

  6. 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.

  7. The divergence theorem for divergence measure vectorfields on sets with fractal boundaries

    Czech Academy of Sciences Publication Activity Database

    Šilhavý, Miroslav

    2009-01-01

    Roč. 14, č. 5 (2009), s. 445-455 ISSN 1081-2865 Institutional research plan: CEZ:AV0Z10190503 Keywords : divergence measure vectorfields * fractal s * divergence theorem Subject RIV: BA - General Mathematics Impact factor: 1.065, year: 2009

  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. Genetic parameters for egg and related characteristics of white Leghorn hens in a subtropical environment

    Directory of Open Access Journals (Sweden)

    Hani M. Sabri

    1999-06-01

    Full Text Available Estimates of heritability and phenotypic and genetic correlations between egg number, weight, specific gravity, mass, and estimated shell weight were obtained, along with phenotypic and genetic correlations of specific gravity and weight with body weight, weight change, metabolizable energy intake, residual feed consumption, and weight and age at sexual maturity. Data were from 350 White Leghorn hens by 50 sires and 175 dams. Heritabilities of the egg traits ranged from 0.20 to 0.55, increasing with age of bird from 26 to 54 weeks of age. Their standard errors ranged from 0.07 (all data to 0.17 (26 to 29 weeks. Phenotypic correlations ranged from 0.80 to -0.13, and genetic correlations from 0.91 to -0.27, depending on egg trait. The highest phenotypic and genetic correlations were between egg number and mass. Genetic correlations for specific gravity and estimated shell weight were, with body weight, -0.02 and 0.56; weight change, 0.29 and 0.44; daily metabolizable energy intake, -0.10 and 0.33; residual consumption, -0.16 and 0.11; age at sexual maturity, -0.61 and -0.46, and weight at sexual maturity, 0.02 and 0.63. Results should contribute to the design of efficient selection programs for economically important traits in hens.Estimativas de herdabilidade e correlações fenotípicas e genéticas entre o número de ovos, peso, gravidade específica, massa e peso estimado da casca foram obtidas, assim como correlações fenotípicas e genéticas de gravidade específica e peso com peso corporal, alterações ponderais, ingestão de energia metabolizável, consumo alimentar residual e peso e idade ao atingir a maturidade sexual. Os dados foram obtidos de 350 galinhas da raça Leghorn Branca obtidas de 50 pais e 175 mães. A herdabilidade dos caracteres dos ovos variou de 0,20 a 0,55, aumentando com a idade da ave de 26 a 54 semanas. O desvio padrão variou de 0,07 (todos os dados a 0,17 (26 a 29 semanas. As correlações fenotípicas variaram

  10. Effect of four processed animal proteins in the diet on behavior in laying hens

    NARCIS (Netherlands)

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

    2011-01-01

    An experiment was performed to investigate the effect of animal versus vegetable protein sources in the diet on the development of behavior in laying hens. A diet containing protein sources of only vegetable origin was compared with four diets, each containing one of four processed animal proteins

  11. Development of hen antihepatitis B antigen IgY-based conjugate for ELISA assay

    Directory of Open Access Journals (Sweden)

    Najat Muayed Nafea

    2015-01-01

    Conclusions: This study showed that laying hens can be used as an alternative source for production of polyclonal antibodies against HBsAg and anti-HBs IgY could be labeled with HRP enzyme and could subsequently be used successfully as secondary antibody in ELISA for detection of HBsAg in the patients sera.

  12. Arsenic in Eggs and Excreta of Laying Hens in Bangladesh: A Preliminary Study

    Science.gov (United States)

    Awal, M. A.; Majumder, Shankar; Mostofa, Mahbub; Khair, Abul; Islam, M. Z.; Rao, D. Ramkishan

    2012-01-01

    The aim of this study was to detect arsenic concentrations in feed, well-water for drinking, eggs, and excreta of laying hens in arsenic-prone areas of Bangladesh and to assess the effect of arsenic-containing feed and well-water on the accumulation of arsenic in eggs and excreta of the same subject. One egg from each laying hen (n=248) and its excreta, feed, and well-water for drinking were collected. Total arsenic concentrations were determined by atomic absorption spectrophotometer, coupled with hydride generator. Effects of arsenic-containing feed and drinking-water on the accumulation of arsenic in eggs and excreta were analyzed by multivariate regression model, using Stata software. Mean arsenic concentrations in drinking-water, feed (dry weight [DW]), egg (wet weight [WW]), and excreta (DW) of hens were 77.3, 176.6, 19.2, and 1,439.9 ppb respectively. Significant (pBangladesh, the arsenic shows low biological transmission capability from body to eggs and, thus, the value was below the maximum tolerable limit for humans. However, arsenic in drinking-water and/or feed makes a significant contribution to the arsenic accumulations in eggs and excreta of laying hens. PMID:23304904

  13. THE INFLUENCE OF AGE HENS ON THE INTENSITY LOAD CAPACITY FROM DIFFERENT WEIGHT GROUPS EGGS

    Directory of Open Access Journals (Sweden)

    Tatjana Pandurević

    2015-05-01

    Full Text Available The aim of this study was to determine the effect of age of hens on the intensity of load from different weight groups eggs. This paper presents the correlation connection, meaning and significance of differences connection for two weight classes (M - 53 to 63g and L – 63g to 73g, which make up the largest part of the total number of eggs produced during the entire production cycle, as well as for all of the eggs produced, as compared to age-laying hens. Between age and intensity of load to 53 weeks of age hens (SN53/34, there is a strong positive, medium and slight correlation coefficients determined and phenotypic correlation are statistically confirmed at the level of P 0.05. Between the age of hens and intensity of load hardest groups (classes eggs (L there is a complete and very strong connections and established correlation coefficients were statistically significant at P <0.001.

  14. Experimental Route to Scanning Probe Hot Electron Nanoscopy (HENs) Applied to 2D Material

    KAUST Repository

    Giugni, Andrea; Torre, Bruno; Allione, Marco; Das, Gobind; Wang, Zhenwei; He, Xin; Alshareef, Husam N.; Di Fabrizio, Enzo M.

    2017-01-01

    for applications in electronics: 2D MoS2 single crystal and a p-type SnO layer. Results are supported by complementary scanning Kelvin probe microscopy, traditional conductive AFM, and Raman measurements. New features highlighted by HEN technique reveal details

  15. QUALITY AND SHELF LIFE EVALUATION OF NUGGETS PREPARED FROM SPENT DUCK AND SPENT HEN MEAT

    Directory of Open Access Journals (Sweden)

    Rajesh Kumar

    2015-12-01

    Full Text Available A study was conducted to compare the quality of nuggets prepared from spent hen and duck meat. The cooked nuggets were analyzed for pH, thiobarbituric acid (TBA, tyrosine value (TV, moisture, fat, protein, total plate count (TPC and sensory evaluations. Nuggets prepared from spent hen meat showed significantly higher (p<0.05 moisture content however pH, fat and protein content were significantly higher (p<0.05 in duck nuggets. TBA values, TVs and (TPC were highest in duck nuggets but were within the acceptable level up to 7th day of refrigerated storage (4±1°C in both types of nuggets. Both nuggets maintain their sensory quality up to 7th day of refrigeration storage but spent hen nuggets were preferred by consumers compared to nuggets prepared from spent duck meat. Result of the study indicated that, despite the comparative differences among these nuggets, spent duck and hen meat could be used for preparation of nutritionally rich and acceptable nuggets.

  16. The Laywell project: welfare implications of changes in production systems for laying hens

    NARCIS (Netherlands)

    Blokhuis, H.J.; Fiks, T.G.C.M.; Bessei, W.; Elson, H.A.; Guémené, D.; Kjaer, J.B.; Maria Levrino, G.A.; Nicol, C.J.; Tauson, R.K.; Weeks, C.A.; Weerd, v.d. H.A.

    2007-01-01

    The conditions under which laying hens are kept remain a major animal welfare concern. It is one of the most intensive forms of animal production and the number of animals involved is very high. Widespread public debate has stimulated the call for more animal friendly, alternative systems to barren

  17. Early life experiences affect the adaptive capacity of rearing hens during infectious challenges

    NARCIS (Netherlands)

    Walstra, I.; Napel, ten J.; Kemp, B.; Schipper, H.; Brand, van den H.

    2010-01-01

    This study aimed to investigate whether pre- and early postnatal experiences of rearing hens contribute to the ability to cope with infectious challenges at an older age. In a 2 × 2 factorial arrangement, 352 Lohmann Brown chicks were exposed to either suboptimal or optimized incubation plus hatch

  18. Improving Tenderness of Spent Layer Hens Meat Using Papaya Leaves (Carica papaya

    Directory of Open Access Journals (Sweden)

    H. O. Abdalla, N. N. A. Ali, F. S. Siddig and S. A. M. Ali*

    2013-01-01

    Full Text Available Two experiments were performed to study the use of papaya leaves as a meat tenderizer. The first experiment was to evaluate the effect of papaya dry leaves added to hen’s diet before slaughter. Spent hens (n=48 were used, half of them were fed a concentrate ration containing10% dried papaya leaves powder (DPLP while others received layer ration (Control, for 10 days. The second experiment involved a comparison between papaya leaves juice (PLJ, fresh papaya leaves (FPL and vinegar solution (VS as marinades applied to meat for one or two hours before cooking. Spent layer hens (n=42 were used for tenderness evaluation method. After slaughtering and preparing the chickens two methods of cooking were used (oven and moist cooking. The cooked parts (breast, thigh and drumstick were subjected to a panel test evaluation according to a designed questionnaire. Addition of dried papaya leaves powder to spent layer hens ration significantly (P≤0.05 increased the level of meat tenderness. Moist cooking had significantly (P≤0.05 improved meat tenderization compared to oven cooking. Meat treated with fresh papaya leaves had significantly (P≤0.05 improved tenderness. It was concluded that wrapping the tough meat of spent layer hens with fresh papaya leaves for one hour and moist cooking improve tenderness of meat.

  19. Does enhancement of specific immune responses predispose laying hens for feather pecking?

    NARCIS (Netherlands)

    Parmentier, H.K.; Rodenburg, T.B.; Vries Reilingh, de G.; Beerda, B.; Kemp, B.

    2009-01-01

    To mimic airborne immune challenges, layer hens were intratracheally and concurrently challenged with various doses of the protein antigen human serum albumin (HuSA) and the pathogen-associated molecular pattern lipopolysaccharide (LPS) at 7 and 13 wk of age. All groups received 1 similar dose of

  20. 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

  1. Effecten van voeding op darmgezondheid van leghennen = Effects of nutrition on intestinal health of laying hens

    NARCIS (Netherlands)

    Veldkamp, T.; Krimpen, van M.M.

    2012-01-01

    Intestinal health is of vital importance for health and welfare of laying hens and nutrition may have a significant contribution. Insoluble non-starch polysaccharides (NSP) and feed additives such as herbs, phytogenic material, probiotics and prebiotics, organic acids and enzymes may have a

  2. ( Vicia faba cv. Fiord) as a protein source for laying hens

    African Journals Online (AJOL)

    Dehulled faba beans were evaluated as an alternative to soybeans as a protein source for laying hens using 240 individually caged birds, 50 weeks of age. Two basal feeds were formulated to the same nutrient specifications but with one containing no faba beans and the other containing 200 g dehulled faba bean meal/kg.

  3. Effect of increasing levels of apparent metabolizable energy on laying hens in barn system.

    Science.gov (United States)

    Kang, Hwan Ku; Park, Seong Bok; Jeon, Jin Joo; Kim, Hyun Soo; Park, Ki Tae; Kim, Sang Ho; Hong, Eui Chul; Kim, Chan Ho

    2018-04-12

    This experiment was to investigate the effect of increasing levels of apparent metabolizable energy (AMEn) on the laying performance, egg quality, blood parameter, blood biochemistry, intestinal morphology, and apparent total tract digestibility (ATTD) of energy and nutrients in diets fed to laying hens. A total of three-hundred twenty 33-week-old Hy-Line Brown laying hens (Gallus domesticus) were evenly assigned to four experimental diets of 2,750, 2,850, 2,950, and 3,050 kcal AMEn/kg in floor with deep litter of rice hulls. There were four replicates of each treatment, each consisting of 20 birds in a pen. AMEn intake was increased (linear, p Feed intake and feed conversion ratio were improved (linear, p hen-day egg production tended to be increased as increasing level of AMEn in diets increased. During the experiment, leukocyte concentration and blood biochemistry (total cholesterol, triglyceride, glucose, total protein, calcium, asparate aminotransferase (AST), and alanine transferase (ALT) were not influenced by increasing level of AMEn in diets. Gross energy and ether extract were increased (linear, p hens fed high AMEn diet (i.e., 3,050 kcal/kg in the current experiment) tended to overconsume energy with a positive effect on feed intake, feed conversion ratio, nutrient digestibility, and intestinal morphology but not in egg production and egg mass.

  4. Spin structure of the 3He from the dd → 3Hen reaction

    International Nuclear Information System (INIS)

    Ladygin, V.P.; Ladygina, N.B.

    1995-01-01

    The polarization observables in the reaction dd → 3 Hen are considered. Their high sensitivity to the 3 He wave function at short distances is shown. Using of both polarized target and beam allows to extend sufficiently the number of possible experiments and to separate 3 He structure from the reaction mechanisms using different relative orientations of initial deuteron spins. 27 refs., 5 figs

  5. Angular dependences of the tensor analyzing powers in the dd→3Hen reaction at intermediate energies

    International Nuclear Information System (INIS)

    Ladygin, V.P.; Ladygina, N.B.

    2002-01-01

    The tensor analyzing powers A yy , A xx , and A xz in the dd→ 3 Hen reaction at intermediate energies are considered in the framework of the one-nucleon-exchange approximation. Their strong sensitivity to the 3 He and deuteron spin structure at short distances is shown

  6. Learning and judgment can be affected by predisposed fearfulness in laying hens

    NARCIS (Netherlands)

    Haas, de Elske N.; Lee, Caroline; Rodenburg, Bas

    2017-01-01

    High fearfulness could disrupt learning and likely affects judgment in animals, especially when it is part of an animals' personality, i.e., trait anxiety. Here, we tested whether high fearfulness affects discrimination learning and judgment bias (JB) in laying hens. Based on the response to an open

  7. 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.

  8. Welfare Quality assessment protocol for laying hens = Welfare Quality assessment protocol voor leghennen

    NARCIS (Netherlands)

    Niekerk, van T.G.C.M.; Gunnink, H.; Reenen, van C.G.

    2012-01-01

    Results of a study on the Welfare Quality® assessment protocol for laying hens. It reports the development of the integration of welfare assessment as scores per criteria as well as simplification of the Welfare Quality® assessment protocol. Results are given from assessment of 122 farms.

  9. Effect of an early bitter taste experience on subsequent feather-pecking behaviour in laying hens

    NARCIS (Netherlands)

    Harlander, A.; Beck, P.S.A.; Rodenburg, T.B.

    2010-01-01

    Recent studies showed that laying hens learn not to peck at bitter-tasting feathers from conspecifics. In the present experiment, feathers of newly hatched chicks were made distasteful by spraying them with a bitter-tasting substance (quinine). It was hypothesized that chicks could detect quinine

  10. Xanthophyll supplementation reduced inflammatory mediators and apoptosis in hens and chicks.

    Science.gov (United States)

    Gao, Y-Y; Jin, L; Ji, J; Sun, B-L; Xu, L-H; Wang, Q-X; Wang, C-K; Bi, Y-Z

    2016-05-01

    This study investigated effects of xanthophylls (containing 40% lutein and 60% zeaxanthin) on gene expression of inflammatory mediators ( [] and []) and apoptosis ( [] and ) of breeding hens and chicks. In Exp. 1, 432 hens were divided into 3 groups and fed diets supplemented with 0 (as the control group), 20, or 40 mg/kg xanthophylls. The liver, duodenum, jejunum, and ileum were sampled after 35 d. Results showed that 40 mg/kg of xanthophyll addition decreased in the liver, in the liver and duodenum, and in the liver and jejunum while increasing level in the liver and jejunum. Experiment 2 was a 2 × 2 factorial design. Male chicks hatched from hens fed 0 or 40 mg/kg xanthophyll diets were fed diets containing either 0 or 40 mg/kg xanthophylls. The liver, duodenum, jejunum, and ileum were sampled at 0, 7, 14, and 21 d after hatching. Results showed that in ovo xanthophylls reduced inflammatory mediators and apoptosis in the liver, duodenum, and jejunum of chicks mainly within 1 wk after hatching, whereas dietary xanthophylls only decreased expression in the liver from 2 wk onward. These results underlined important anti-inflammatory and antiapoptotic effects of maternal but not progeny dietary xanthophylls. In conclusion, xanthophylls can suppress inflammatory mediators and apoptosis in different tissues of hens and chicks.

  11. The fearful feather pecker : applying the principles to practice to prevent feather pecking in laying hens

    NARCIS (Netherlands)

    Haas, de E.N.

    2014-01-01

    Billions of laying hens are kept worldwide. Severe feather pecking (SFP) is a behaviour which occurs with a high prevalence on commercial farms. SFP, the pecking and plucking of feathers of another bird, induces pain and stress and can ultimately lead to cannibalism. Moreover, SFP can occur if a

  12. Parents and Early Life Environment Affect Behavioral Development of Laying Hen Chickens

    NARCIS (Netherlands)

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

    2014-01-01

    Severe feather pecking (SFP) in commercial laying hens is a maladaptive behavior which is associated with anxiety traits. Many experimental studies have shown that stress in the parents can affect anxiety in the offspring, but until now these effects have been neglected in addressing the problem of

  13. Magnetic cation exchange isolation of lysozyme from native hen egg white

    Czech Academy of Sciences Publication Activity Database

    Šafařík, Ivo; Maděrová, Zdeňka; Tokar, O.; Šafaříková, Miroslava

    2007-01-01

    Roč. 45, - (2007), s. 355-359 ISSN 1330-9862 R&D Projects: GA MŠk(CZ) 1P05OC053 Institutional research plan: CEZ:AV0Z60870520 Keywords : magnetic separation * lysozyme * hen egg white Subject RIV: EI - Biotechnology ; Bionics Impact factor: 0.906, year: 2007

  14. Parents and early life environment affect behavioral development of laying hen chickens

    NARCIS (Netherlands)

    Haas, Elske N. de; Bolhuis, J. Elizabeth; Kemp, Bas; Groothuis, Ton G.G.; Rodenburg, T. Bas

    Severe feather pecking (SFP) in commercial laying hens is a maladaptive behavior which is associated with anxiety traits. Many experimental studies have shown that stress in the parents can affect anxiety in the offspring, but until now these effects have been neglected in addressing the problem of

  15. Adaptive divergence with gene flow in incipient speciation of Miscanthus floridulus / sinensis complex (Poaceae)

    KAUST Repository

    Huang, Chao-Li; Ho, Chuan-Wen; Chiang, Yu-Chung; Shigemoto, Yasumasa; Hsu, Tsai-Wen; Hwang, Chi-Chuan; Ge, Xue-Jun; Chen, Charles; Wu, Tai-Han; Chou, Chang-Hung; Huang, Hao-Jen; Gojobori, Takashi; Osada, Naoki; Chiang, Tzen-Yuh

    2014-01-01

    Young incipient species provide ideal materials for untangling the process of ecological speciation in the presence of gene flow. The Miscanthus floridulus/sinensis complex exhibits diverse phenotypic and ecological differences despite recent divergence (approximately 1.59million years ago). To elucidate the process of genetic differentiation during early stages of ecological speciation, we analyzed genomic divergence in the Miscanthus complex using 72 randomly selected genes from a newly assembled transcriptome. In this study, rampant gene flow was detected between species, estimated as M=3.36x10(-9) to 1.20x10(-6), resulting in contradicting phylogenies across loci. Nevertheless, beast analyses revealed the species identity and the effects of extrinsic cohesive forces that counteracted the non-stop introgression. As expected, early in speciation with gene flow, only 3-13 loci were highly diverged; two to five outliers (approximately 2.78-6.94% of the genome) were characterized by strong linkage disequilibrium, and asymmetrically distributed among ecotypes, indicating footprints of diversifying selection. In conclusion, ecological speciation of incipient species of Miscanthus probably followed the parapatric model, whereas allopatric speciation cannot be completely ruled out, especially between the geographically isolated northern and southern M.sinensis, for which no significant gene flow across oceanic barriers was detected. Divergence between local ecotypes in early-stage speciation began at a few genomic regions under the influence of natural selection and divergence hitchhiking that overcame gene flow.

  16. Adaptive divergence with gene flow in incipient speciation of Miscanthus floridulus / sinensis complex (Poaceae)

    KAUST Repository

    Huang, Chao-Li

    2014-11-11

    Young incipient species provide ideal materials for untangling the process of ecological speciation in the presence of gene flow. The Miscanthus floridulus/sinensis complex exhibits diverse phenotypic and ecological differences despite recent divergence (approximately 1.59million years ago). To elucidate the process of genetic differentiation during early stages of ecological speciation, we analyzed genomic divergence in the Miscanthus complex using 72 randomly selected genes from a newly assembled transcriptome. In this study, rampant gene flow was detected between species, estimated as M=3.36x10(-9) to 1.20x10(-6), resulting in contradicting phylogenies across loci. Nevertheless, beast analyses revealed the species identity and the effects of extrinsic cohesive forces that counteracted the non-stop introgression. As expected, early in speciation with gene flow, only 3-13 loci were highly diverged; two to five outliers (approximately 2.78-6.94% of the genome) were characterized by strong linkage disequilibrium, and asymmetrically distributed among ecotypes, indicating footprints of diversifying selection. In conclusion, ecological speciation of incipient species of Miscanthus probably followed the parapatric model, whereas allopatric speciation cannot be completely ruled out, especially between the geographically isolated northern and southern M.sinensis, for which no significant gene flow across oceanic barriers was detected. Divergence between local ecotypes in early-stage speciation began at a few genomic regions under the influence of natural selection and divergence hitchhiking that overcame gene flow.

  17. Genetic Coupling of Female Mate Choice with Polygenic Ecological Divergence Facilitates Stickleback Speciation.

    Science.gov (United States)

    Bay, Rachael A; Arnegard, Matthew E; Conte, Gina L; Best, Jacob; Bedford, Nicole L; McCann, Shaugnessy R; Dubin, Matthew E; Chan, Yingguang Frank; Jones, Felicity C; Kingsley, David M; Schluter, Dolph; Peichel, Catherine L

    2017-11-06

    Ecological speciation with gene flow is widespread in nature [1], but it presents a conundrum: how are associations between traits under divergent natural selection and traits that contribute to assortative mating maintained? Theoretical models suggest that genetic mechanisms inhibiting free recombination between loci underlying these two types of traits (hereafter, "genetic coupling") can facilitate speciation [2-4]. Here, we perform a direct test for genetic coupling by mapping both divergent traits and female mate choice in a classic model of ecological speciation: sympatric benthic and limnetic threespine stickleback (Gasterosteus aculeatus). By measuring mate choice in F2 hybrid females, we allowed for recombination between loci underlying assortative mating and those under divergent ecological selection. In semi-natural mating arenas in which females had access to both benthic and limnetic males, we found that F2 females mated with males similar to themselves in body size and shape. In addition, we found two quantitative trait loci (QTLs) associated with female mate choice that also predicted female morphology along the benthic-limnetic trait axis. Furthermore, a polygenic genetic model that explains adaptation to contrasting benthic and limnetic feeding niches [5] also predicted F2 female mate choice. Together, these results provide empirical evidence that genetic coupling of assortative mating with traits under divergent ecological selection helps maintain species in the face of gene flow, despite a polygenic basis for adaptation to divergent environments. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Vibhakti Divergence between Sanskrit and Hindi

    Science.gov (United States)

    Shukla, Preeti; Shukl, Devanand; Kulkarni, Amba

    Translation divergence at various levels between languages arises due to the different conventions followed by different languages for coding the information of grammatical relations. Though Sanskrit and Hindi belong to the same Indo-Aryan family and structurally as well as lexically Hindi inherits a lot from Sanskrit, yet divergences are observed at the level of function words such as vibhaktis. Pāṇini in his Aṣṭādhyāyī has assigned a default vibhakti to kārakas alongwith many scopes for exceptions. He handles these exceptions either by imposing a new kāraka role or by assigning a special vibhakti. However, these methods are not acceptable in Hindi in toto. Based on the nature of deviation, we propose seven cases of divergences in this paper.

  19. 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.

  20. 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.

  1. Applying the principles of welfare and quality of production in the organic farm of the laying hens

    OpenAIRE

    Jana Zdechovanová; Martin Mellen; Mária Angelovičová

    2013-01-01

    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...

  2. Leptin receptor signaling inhibits ovarian follicle development and egg laying in chicken hens

    Science.gov (United States)

    2014-01-01

    Background Nutrition intake during growth strongly influences ovarian follicle development and egg laying in chicken hens, yet the underlying endocrine regulatory mechanism is still poorly understood. The relevant research progress is hindered by difficulties in detection of leptin gene and its expression in the chicken. However, a functional leptin receptor (LEPR) is present in the chicken which has been implicated to play a regulatory role in ovarian follicle development and egg laying. The present study targeted LEPR by immunizing against its extracellular domain (ECD), and examined the resultant ovarian follicle development and egg-laying rate in chicken hens. Methods Hens that have been immunized four times with chicken LEPR ECD were assessed for their egg laying rate and feed intake, numbers of ovarian follicles, gene expression profiles, serum lipid parameters, as well as STAT3 signaling pathway. Results Administrations of cLEPR ECD antigen resulted in marked reductions in laying rate that over time eventually recovered to the levels exhibited by the Control hens. Together with the decrease in egg laying rate, cLEPR-immunized hens also exhibited significant reductions in feed intake, plasma concentrations of glucose, triglyceride, high-density lipoprotein, and low-density lipoprotein. Parallelled by reductions in feed intake, mRNA gene expression levels of AgRP, orexin, and NPY were down regulated, but of POMC, MC4R and lepR up-regulated in Immunized hen hypothalamus. cLEPR-immunization also promoted expressions of apoptotic genes such as caspase3 in theca and fas in granulosa layer, but severely depressed IGF-I expression in both theca and granulosa layers. Conclusions Immunization against cLEPR ECD in egg-laying hens generated antibodies that mimic leptin bioactivity by enhancing leptin receptor transduction. This up-regulated apoptotic gene expression in ovarian follicles, negatively regulated the expression of genes that promote follicular development

  3. Diverging expectations in buyer-seller relationships

    DEFF Research Database (Denmark)

    Andersen, Poul Houman; Christensen, Poul Rind; Damgaard, Torben

    2009-01-01

    Many firms assume that outsourcing partnerships may allow them to strengthen their overall competitiveness. Lured by its intuitive appeal, several enter into such partnerships, only to realize that they represent a marginal rather than a magical solution to their quest for increasing market...... performance. We explore the proposed impact of diverging relationship norms on relationship expectations using data from an ongoing field study of Danish buyers and Chinese suppliers. We link these diverging expectations to the business practices of Danish buyers and Chinese and their institutional contexts...

  4. Evolutionary divergence in sexual signals: Insights from within and among barn swallow populations

    Science.gov (United States)

    Wilkins, Matthew Reed

    A wealth of studies across diverse animal groups indicate the importance of sexual selection in shaping phenotypes within and across breeding populations. In recent decades, much research has focused on how divergent sexual selection pressures among populations may lead to speciation. For my first dissertation chapter, I performed a literature review on the causes and consequences of evolutionary divergence in acoustic signals and developed the acoustic window conceptual framework for understanding the contributions of selection, genetic drift, and evolutionary constraint to signal divergence. Further, I found that sexual selection explains acoustic differences between recently diverged populations of the best-studied taxa. However, the relative contributions of ecological selection, sexual selection, and drift to acoustic divergence have not typically been considered within the same study systems. The remainder of my dissertation used the Northern Hemisphere-distributed barn swallow ( Hirundo rustica) species complex as a model system to study sender-receiver dynamics, intra- and intersexual selection pressures, and visual and acoustic signal interactions at the local scale, and signal divergence across populations at the global scale. From song recordings taken across 19 sampling sites, spanning five of six described subspecies, I demonstrated considerable conservation in song structure. However, temporal traits were highly divergent across subspecies, and in particular, the speed of the terminal trill of songs. In a detailed study of the multimodal communication system of the barn swallow (including visual and acoustic traits), I demonstrated that males and females use different types of signals to mediate competition and mate choice. One of the only exceptions to this rule was trill rate, which was also implicated in song divergence across populations. In order to test the function of trill rate in communication, I performed a two-year playback study within the

  5. Plasma dispositions and concentrations of ivermectin in eggs following treatment of laying hens.

    Science.gov (United States)

    Cirak, V Y; Aksit, D; Cihan, H; Gokbulut, C

    2018-05-01

    To determine the plasma disposition and concentrations of ivermectin (IVM) in eggs produced by laying hens following S/C, oral and I/V administration. Twenty-four laying hens, aged 37 weeks and weighing 1.73 (SD 0.12) kg were allocated to three groups of eight birds. The injectable formulation of IVM was administered either orally, S/C, or I/V, at a dose of 0.2 mg/kg liveweight, following dilution (1:5, v/v) with propylene glycol. Heparinised blood samples were collected at various times between 0.25 hours and 20 days after drug administration. Eggs produced by hens were also collected daily throughout the study period. Samples of plasma and homogenised egg were analysed using HPLC. Maximum concentrations of IVM in plasma and mean residence time of IVM were lower after oral (10.2 (SD 7.2) ng/mL and 0.38 (SD 0.14) days, respectively) than after S/C (82.9 (SD 12.4) ng/mL and 1.05 (SD 0.24) days, respectively) administration (pV administration, and until 15 days after S/C administration. Peak concentrations of IVM were 15.7, 23.3 and 1.9 µg/kg, observed 2, 5 and 4 days after I/V, S/C and oral administration, respectively. The low plasma bioavailability of IVM observed after oral administration in laying hens could result in lower efficacy or subtherapeutic plasma concentrations, which may promote the development of parasitic drug resistance. Due to high IVM residues in eggs compared to the maximum residue limits for other food-producing animal species, a withdrawal period should be necessary for eggs after IVM treatment in laying hens.

  6. Utilizing fungus myceliated grain for molt induction and performance in commercial laying hens.

    Science.gov (United States)

    Willis, W L; Isikhuemhen, O S; Allen, J W; Byers, A; King, K; Thomas, C

    2009-10-01

    Molting in poultry is used to rejuvenate hens for a second or third laying cycle. Feed withdrawal was once the most effective method used for molt induction; however, it has being phased out due to food safety and animal welfare concerns. This study evaluated the utilization of fungus myceliated grain as a safe and effective alternative for inducing molt, enhancing immunity, reducing Salmonella growth, and returning to egg production. Laying hens were subjected to 1 of 5 treatments: 1) nonfed (NF), 2) full-fed (FF), 3) fungus myceliated meal (FM), 4) 90% fungus myceliated meal+10% standard layer ration (FM-90), and 5) 90% alfalfa meal+10% fungus myceliated meal (AF-90). Each treatment condition was replicated 9 times during a 9-d molt period. The results revealed that egg production for treatments 1 and 3 ceased completely by d 5, whereas hens in treatments 4 and 5 ceased egg production by d 6. The percentage of BW loss decreased significantly (P<0.05) in treatments 1 (57%), 2 (8%), 3 (35%), 4 (37%), and 5 (44%). Ovary weights of hens fed all molting diets decreased significantly from the full-fed control but did not differ significantly (P<0.05) from each other. Salmonella population in the crop, ovary, and ceca from hens differed significantly (P<0.05) among treatments. Return to egg production differed between treatments with higher production beginning in treatment 3 and ending in treatment 5. Antibody titers did differ (P<0.05) among treatments. From these results, fungus myceliated meal appears to be a viable alternative to conventional feed withdrawal and other methods for the successful induction of molt and retention of postmolt performance.

  7. Effect of nutrient dilution on feed intake, eating time and performance of hens in early lay.

    Science.gov (United States)

    van Krimpen, M M; Kwakkel, R P; André, G; van der Peet-Schwering, C M C; den Hartog, L A; Verstegen, M W A

    2007-08-01

    1. An experiment with 480 ISA Brown layers was conducted to measure the effect of dietary energy (11.8, 11.2 and 10.6 MJ/kg) and non-starch polysaccharides (NSP) (128, 146 and 207 g/kg) concentration, soluble NSP content (64 and 85 g/kg), particle size distribution of the NSP fraction (fine and coarse) and feed form (mash and crumble) on feed intake, eating time and egg performance of laying hens in early lay (from 18 to 26 weeks of age). Twelve experimental diets were tested, each replicated 4 times. 2. Laying hens in early lay that were fed low- or high-NSP diets were able to compensate for 10% dietary dilution by 9.5 and 4.9% higher feed intakes, respectively. Feeding crumble or coarsely ground mash did not affect feed intake. 3. Eating time of the hens fed the undiluted diets increased over the experimental period from 16.4 to 24.6% of the observation period, but was not affected by sand or grit addition, particle size distribution or feed form. Feeding high-NSP diets increased eating time by 22%. 4. Egg performance and body weight gain of the hens that were fed low-NSP or high-NSP diets were similar or better compared to the undiluted diets, whereas coarse grinding of the diets showed 7 to 10% lower egg performance and weight gain. Egg performance and weight gain were not affected by feed form. 5. It is concluded that hens in early lay, fed energy-diluted diets, by adding sand or grit (low-NSP) or NSP-rich raw materials (high-NSP) to the control diet, were able to increase their feed intake, resulting in energy intake and egg performance comparable to the control group. Supplementing diets with insoluble NSP also decreased eating rate. Prolonged eating time using insoluble NSP could be useful in reducing feather pecking behaviour.

  8. 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

  9. Prevalence of gastrointestinal helminth infections in free-range laying hens under mountain farming production conditions.

    Science.gov (United States)

    Wuthijaree, K; Lambertz, C; Gauly, M

    2017-12-01

    1. A cross-sectional study was conducted from September 2015 to July 2016 in South Tyrol, Northern Italy to examine the prevalence of gastrointestinal helminths in free-range laying hens under mountain farming production conditions. 2. A total of 280 laying hens from 14 free-range mountain farms (4 organic, 10 conventional) were randomly collected at the end of the laying period. Faecal samples were taken to analyse faecal egg counts (FEC) and faecal oocyst counts (FOC). The gastrointestinal tracts were removed post mortem and examined for the presence of helminths. 3. In faeces, FEC values averaged 258 eggs per g of faeces, which were dominated by Ascaridia galli and Heterakis gallinarum. Mean FOC was 80 oocysts/g. In the gastrointestinal tract, at least one nematode species was found in 99.3% of the examined hens. H. gallinarum was the most prevalent nematode (95.7%), followed by Capillaria spp. (66.8%) and A. galli (63.6%). Thirty per cent of the chickens were infected with cestodes (tapeworms). Correlation coefficients between worm counts of H. gallinarum, Capillaria spp. and A. galli ranged from 0.41 to 0.51. 5. The helminth prevalence did not differ between conventional and organic farms, whereas total worm burden was higher in organic compared with conventional farms (318.9 vs. 112.0). Prevalence and infection intensity did not differ between farms that used anthelmintic treatments and those that did not. 6. In conclusion, free-range laying hens under the studied mountain farming conditions are at high risk of nematode infection, especially in organic systems. The vast majority of hens are subclinical infected with at least one helminth species.

  10. Kinetic study of chlordecone orally given to laying hens (Gallus domesticus).

    Science.gov (United States)

    Jondreville, Catherine; Fournier, Agnès; Mahieu, Maurice; Feidt, Cyril; Archimède, Harry; Rychen, Guido

    2014-11-01

    The former use of chlordecone (CLD) in the French West Indies has resulted in long-term pollution of soils. In this area, CLD may be transferred into eggs of hens reared outdoors, through soil ingestion. In order to assess this risk, a kinetic study involving the contamination of laying hens (22 weeks of age) with a diet containing 500 μg CLD kg(-1) during 42 d, followed by a depuration period of 35 d was carried out. Forty-four hens were sequentially slaughtered all over the experimental period and their liver, egg, abdominal fat and serum were collected. Two additional edible tissues, pectoral and leg muscles, were collected in hens slaughtered at the end of the contamination period. The depuration half-life of CLD in liver, egg, abdominal fat and serum was estimated at 5.0 ± 0.38 (mean ± SE), 5.5 ± 0.29, 5.3 ± 0.37 and 5.1 ± 0.66 d, respectively. CLD concentration at the end of the contamination period reached 1640 ± 274, 460 ± 41, 331 ± 23, and 213 ± 8.5 μg kg(-1) fresh matter (FM), respectively. The corresponding concentrations in pectoral and leg muscles were 119 ± 8.4, 127 ± 11 μg kg(-1) FM, respectively. The steady state carry over rate of CLD in eggs reached 43 ± 7.6%. This experiment demonstrates the preferential accumulation of CLD in liver, its significant transfer to eggs and its quite short half-life. It is concluded that raising hens on even mildly contaminated areas would lead to products exceeding the regulatory maximum residue limit of 20 μg CLD kg(-1). Copyright © 2014 Elsevier Ltd. All rights reserved.

  11. Supplementation of xanthophylls increased antioxidant capacity and decreased lipid peroxidation in hens and chicks.

    Science.gov (United States)

    Gao, Yu-Yun; Xie, Qing-Mei; Ma, Jing-Yun; Zhang, Xiang-Bin; Zhu, Ji-Mei; Shu, Ding-Ming; Sun, Bao-Li; Jin, Ling; Bi, Ying-Zuo

    2013-03-28

    The present study investigated the effects of xanthophyll supplementation on production performance, antioxidant capacity (measured by glutathione peroxidase, superoxide dismutase (SOD), catalase, total antioxidant capacity (T-AOC), and reduced glutathione:oxidised glutathione ratio (GSH:GSSG)) and lipid peroxidation (measured by malondialdehyde (MDA)) in breeding hens and chicks. In Expt 1, 432 hens were fed diets supplemented with 0 (control group), 20 or 40 mg xanthophyll/kg diet. Blood samples were taken at 7, 14, 21, 28 and 35 d of the trial. Liver and jejunal mucosa were sampled at 35 d. Both xanthophyll groups improved serum SOD at 21 and 28 d, serum T-AOC at 21 d and liver T-AOC, and serum GSH:GSSG at 21, 28 and 35 d and liver GSH:GSSG. Xanthophylls also decreased serum MDA at 21 d in hens. Expt 2 was a 2 × 2 factorial design. Male chicks hatched from 0 or 40 mg in ovo xanthophyll/kg diet of hens were fed a diet containing either 0 or 40 mg xanthophyll/kg diet. Liver samples were collected at 0, 7, 14 and 21 d after hatching. Blood samples were also collected at 21 d. In ovo-deposited xanthophylls increased antioxidant capacity and decreased MDA in the liver mainly within 1 week after hatching. Maternal effects gradually vanished during 1-2 weeks after hatching. Dietary xanthophylls increased antioxidant capacity and decreased MDA in the liver and serum mainly from 2 weeks onwards. Data suggested that xanthophyll supplementation enhanced antioxidant capacity and reduced lipid peroxidation in different tissues of hens and chicks.

  12. Xanthophylls increased HDLC level and nuclear factor PPARγ, RXRγ and RARα expression in hens and chicks.

    Science.gov (United States)

    Gao, Y-Y; Jin, L; Peng, H; Xu, L-H; Wang, Q-X; Ji, J; Wang, C-K; Bi, Y-Z

    2018-02-01

    This study was designed to investigate effects of xanthophylls on serum lipid profile (triglyceride, TG; cholesterol, CHO; high-density lipoprotein cholesterol, HDLC; and low-density lipoprotein cholesterol, LDLC) and nuclear factor (peroxisome proliferator-activated receptor gamma, PPARγ; PPAR gamma coactivator 1 alpha, PGC1α; retinoid X receptor gamma, RXRγ; and retinoic acid receptor alpha, RARα) gene expression of breeding hens and chicks. In experiment 1, 432 hens were divided into three groups and fed diets supplemented with 0 (as control group), 20 or 40 mg/kg xanthophylls. Blood was sampled at 7, 14, 21, 28 and 35 days of trial. Liver, duodenum, jejunum and ileum were sampled at 35 days of trial. Results showed that serum HDLC level of hens was increased after dietary 40 mg/kg xanthophyll addition for 21, 28 and 35 days, while serum TG, CHO and LDLC were not affected. Xanthophyll addition also increased PPARγ expression in jejunum, RXRγ expression in duodenum and jejunum, and RARα expression in liver and duodenum. Experiment 2 was a 2 × 2 factorial design. Male chicks hatched from 0 or 40 mg/kg xanthophyll diet of hens were fed diet containing either 0 or 40 mg/kg xanthophylls. Liver, duodenum, jejunum and ileum were sampled at 0, 7, 14 and 21 days after hatching. Blood samples were also collected at 21 days. Results showed that in ovo xanthophylls elevated PPARγ in duodenum and jejunum, and RXRγ and RARα in liver of chicks mainly within 1 week after hatching, while dietary xanthophylls increased serum HDLC level and PPARγ and RXRγ in liver from 2 weeks onwards. In conclusion, our research suggested xanthophylls can regulate serum lipid profile and nuclear factor expression in hens and chicks. © 2017 Blackwell Verlag GmbH.

  13. 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]).

  14. Highly divergent 16S rRNA sequences in ribosomal operons of Scytonema hyalinum (Cyanobacteria.

    Directory of Open Access Journals (Sweden)

    Jeffrey R Johansen

    Full Text Available A highly divergent 16S rRNA gene was found in one of the five ribosomal operons present in a species complex currently circumscribed as Scytonema hyalinum (Nostocales, Cyanobacteria using clone libraries. If 16S rRNA sequence macroheterogeneity among ribosomal operons due to insertions, deletions or truncation is excluded, the sequence heterogeneity observed in S. hyalinum was the highest observed in any prokaryotic species thus far (7.3-9.0%. The secondary structure of the 16S rRNA molecules encoded by the two divergent operons was nearly identical, indicating possible functionality. The 23S rRNA gene was examined for a few strains in this complex, and it was also found to be highly divergent from the gene in Type 2 operons (8.7%, and likewise had nearly identical secondary structure between the Type 1 and Type 2 operons. Furthermore, the 16S-23S ITS showed marked differences consistent between operons among numerous strains. Both operons have promoter sequences that satisfy consensus requirements for functional prokaryotic transcription initiation. Horizontal gene transfer from another unknown heterocytous cyanobacterium is considered the most likely explanation for the origin of this molecule, but does not explain the ultimate origin of this sequence, which is very divergent from all 16S rRNA sequences found thus far in cyanobacteria. The divergent sequence is highly conserved among numerous strains of S. hyalinum, suggesting adaptive advantage and selective constraint of the divergent sequence.

  15. 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.

  16. Adaptive divergence in resistance to herbivores in Datura stramonium

    Directory of Open Access Journals (Sweden)

    Guillermo Castillo

    2015-11-01

    Full Text Available Defensive traits exhibited by plants vary widely across populations. Heritable phenotypic differentiation is likely to be produced by genetic drift and spatially restricted gene flow between populations. However, spatially variable selection exerted by herbivores may also give rise to differences among populations. To explore to what extent these factors promote the among-population differentiation of plant resistance of 13 populations of Datura stramonium, we compared the degree of phenotypic differentiation (PST of leaf resistance traits (trichome density, atropine and scopolamine concentration against neutral genetic differentiation (FST at microsatellite loci. Results showed that phenotypic differentiation in defensive traits among-population is not consistent with divergence promoted by genetic drift and restricted gene flow alone. Phenotypic differentiation in scopolamine concentration was significantly higher than FST across the range of trait heritability values. In contrast, genetic differentiation in trichome density was different from FST only when heritability was very low. On the other hand, differentiation in atropine concentration differed from the neutral expectation when heritability was less than or equal to 0.3. In addition, we did not find a significant correlation between pair-wise neutral genetic distances and distances of phenotypic resistance traits. Our findings reinforce previous evidence that divergent natural selection exerted by herbivores has promoted the among-population phenotypic differentiation of defensive traits in D. stramonium.

  17. 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.

  18. Stora's fine notion of divergent amplitudes

    Directory of Open Access Journals (Sweden)

    Joseph C. Várilly

    2016-11-01

    Full Text Available Stora and coworkers refined the notion of divergent quantum amplitude, somewhat upsetting the standard power-counting recipe. This unexpectedly clears the way to new prototypes for free and interacting field theories of bosons of any mass and spin.

  19. Taming infrared divergences in the effective potential

    Energy Technology Data Exchange (ETDEWEB)

    Elias-Miro, J. [IFAE, Univ. Autonoma de Barcelona (Spain); Universitat Autonoma de Barcelona (Spain). Dept. de Fisica; Espinosa, J.R. [IFAE, Univ. Autonoma de Barcelona (Spain); ICREA, Institucio Catalana de Recerca i Estudis Avancats, Barcelona (Spain); Konstandin, T. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2014-06-15

    The Higgs effective potential in the Standard Model (SM), calculated perturbatively, generically suffers from infrared (IR) divergences when the (field-dependent) tree-level mass of the Goldstone bosons goes to zero. Such divergences can affect both the potential and its first derivative and become worse with increasing loop order. In this paper we show that these IR divergences are spurious, we perform a simple resummation of all IR-problematic terms known (up to three loops) and explain how to extend the resummation to cure all such divergences to any order. The method is of general applicability and would work in scenarios other than the SM. Our discussion has some bearing on a scenario recently proposed as a mechanism for gauge mediation of scale breaking in the ultraviolet, in which it is claimed that the low-energy Higgs potential is non-standard. We argue that all non-decoupling effects from the heavy sector can be absorbed in the renormalization of low-energy parameters leading to a SM-like effective theory.

  20. Bounding the bias of contrastive divergence learning

    DEFF Research Database (Denmark)

    Fischer, Anja; Igel, Christian

    2011-01-01

    Optimization based on k-step contrastive divergence (CD) has become a common way to train restricted Boltzmann machines (RBMs). The k-step CD is a biased estimator of the log-likelihood gradient relying on Gibbs sampling. We derive a new upper bound for this bias. Its magnitude depends on k...