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Sample records for mexican charolais herds

  1. Forecasting the Brazilian real and the Mexican peso: Asymmetric loss, forecast rationality, and forecaster herding

    DEFF Research Database (Denmark)

    Stadtmann, Georg; Fritsche, Ulrich; Pierdzioch, Christian

    2015-01-01

    Using forecasts of exchange rates of the Brazilian real and the Mexican peso against the US dollar, we analyze the symmetry of the loss function of exchange-rate forecasters and the rationality of their forecasts. Symmetry of the loss function can be rejected for some forecasters but not all. Even...... when allowing for asymmetric loss functions, the predictions of some forecasters do not fit the traditional definition of rational forecasts. We interpret our results in terms of recent research on forecaster (anti-)herding....

  2. First calving date and productivity of Charolais cows in Coahuila, Mexico.

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    Ramiro López-Trujillo

    2016-06-01

    Full Text Available The aim of the study was to evaluate the effect of first calving date of Charolais cows on their productive efficiency in a cow- calf system in the southeast of Coahuila, Mexico. Ten- year records of the herd were analyzed to test such effect. Each cow (n=201 was assigned to one of the two consecutive calving groups of 42 days each, according to the date of its first calving. Cows calving early lost this trait in subsequent parturitions; calving date repeatability (Ri was 0.25, indicating that improvement of herd fertility, discarding cows that first calving was late, would be modest. Weaning age and weight of calves showed similar tendencies (p≤0.01. Ri for calf’s weaning weight and cow’s weaning efficiency were 0.11 and 0.27, respectively. Cow’s weaning weight (Ri=0.66 presented a quadratic response to parity number, but late first calving cows consistently weighed less. Cows, that first calving was at the beginning of the calving season, had better productive efficiency as a result of their performance at first calving. . Low calving date Ri indicates that this variable was sensitive to the reproductive and nutritional management of the herd.

  3. The scurs inheritance: new insights from the French Charolais breed

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    Gautier Mathieu

    2009-07-01

    Full Text Available Abstract Background Polled animals are valued in cattle industry because the absence of horns has a significant economic impact. However, some cattle are neither polled nor horned but have so-called scurs on their heads, which are corneous growths loosely attached to the skull. A better understanding of the genetic determinism of the scurs phenotype would help to fine map the polled locus. To date, only one study has attempted to map the scurs locus in cattle. Here, we have investigated the inheritance of the scurs phenotype in the French Charolais breed and examined whether the previously proposed localisation of the scurs locus on bovine chromosome 19 could be confirmed or not. Results Our results indicate that the inheritance pattern of the scurs phenotype in the French Charolais breed is autosomal recessive with complete penetrance in both sexes, which is different from what is reported for other breeds. The frequency of the scurs allele (Sc reaches 69.9% in the French Charolais population. Eleven microsatellite markers on bovine chromosome 19 were genotyped in 267 offspring (33 half-sib and full-sib families. Both non-parametric and parametric linkage analyses suggest that in the French Charolais population the scurs locus may not map to the previously identified region. A new analysis of an Angus-Hereford and Hereford-Hereford pedigree published in 1978 enabled us to calculate the frequency of the Sc allele in the Hereford breed (89.4% and to study the penetrance of this allele in males heterozygous for both polled and scurs loci (40%. This led us to revise the inheritance pattern of the scurs phenotype proposed for the Hereford breed and to suggest that allele Sc is not fully but partially dominant in double heterozygous males while it is always recessive in females. Crossbreeding involving the Charolais breed and other breeds gave results similar to those reported in the Hereford breed. Conclusion Our results suggest the existence of

  4. ASSESSMENT OF CHAROLAIS BULLS POPULATION STRUCTURE BASED ON SNPs ANALYSES

    OpenAIRE

    Nina Moravčíková; Tomáš Minarovič; Anna Trakovická

    2014-01-01

    The aim of this study was identification of SNPs in leptin (LEP), leptin receptor (LEPR), growth hormone (GH) and specific pituitary transcription factor (Pit-1) genes in order to analyze genetic structure of Charolais bulls’ population. The total numbers of genomic DNA samples were taken from 52 breeding bulls and analyzed by PCR-RFLP method. After digestion with restriction enzymes were detected in bulls’ population alleles with frequency: LEP/Sau3AI A 0.83 and B 0.17 (±0.037); LEPR/BseGI C...

  5. CALVING ANALYSIS IN COWS OF CHAROLAIS BREED AT SELECTED FARM

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    KLÁRA VAVRIŠÍNOVÁ

    2001-09-01

    Full Text Available At our work we have analysed the organisation of calving in Charolais breed during the years from 1998 to 2001 at selected farm. Our monitoring of calving during winter season (from January to February shows the percentage of calving was in particular years ranged from 43.2 to 71.1. The most calves were born in February. We found out (total all years diffi cult calving (value 3 in 2 cases in April (1998 and 1999 and 1 case in February (1998 and 1 in March (1999. Calving marked with value 2 (total of all years we found out in January (2 cases, February (3 cases, March (4 cases and from September to December past one case. From 18 cases of diffi cult calving what we found out, 11 calves (61.11 % come from CHV 529 bull. In calves born by normal calving was found out average weight 34.75 kg, in ones born by calving with level 2 of diffi culty 36.36 kg, and in calves born by calving with diffi culty 3 was recorded average weight 41.5 kg. Recorded weight at 210 days of age in mostly cases was similar like in published breed standard.

  6. Genetic parameters for calving ease, gestation length, and birth weight in Charolais cattle.

    Science.gov (United States)

    Mujibi, F D N; Crews, D H

    2009-09-01

    In this study, a 3-trait linear model was used to obtain genetic parameters for direct and maternal components of calving ease (CE), gestation length (GEST), and birth weight (BWT). Calving ease scores were transformed into Snell scores and expressed as percent unassisted calving (SC), ranging from 0 to 100% (least to greatest ease). A total of 40,420 records (n = 14,403 for CE) were obtained from the Canadian Charolais Association field database. The animal model included fixed effects of contemporary group (herd x year of birth combinations), age of heifer, and sex of calf (only for CE), whereas random effects included direct and maternal genetic effects, residual error, and permanent environmental effects (for CE). The BWT and GEST were preadjusted for age of dam and sex of calf effects. Variance components were estimated using REML. Mean SC was 83.31% (SD = 23.30) and ranged from 3.44 to 100%. Mean BWT was 46.54 kg (SD = 4.79), whereas mean GEST was 286.48 d (SD = 4.93). Direct heritability estimates for SC, BWT, and GEST were 0.14 +/- 0.02, 0.46 +/- 0.03, and 0.62 +/- 0.04, respectively, and maternal heritability estimates were 0.06 +/- 0.02, 0.14 +/- 0.02, and 0.10 +/- 0.02, respectively. The permanent environmental effect as a proportion of SC phenotypic variance was 0.35 +/- 0.11, indicating a large influence on CE. Genetic correlations of direct SC with direct BWT and GEST were -0.93 +/- 0.04 and -0.38 +/- 0.08, respectively, whereas maternal correlations were -0.69 +/- 0.14 and -0.49 +/- 0.17, respectively, illustrating the importance of including both traits in CE evaluations. Within trait direct x maternal genetic correlations were substantial and negative. Regression of average direct and average maternal EBV on year of birth yielded significant genetic trends for the direct effects of BWT, GEST, and CE, whereas no trends were detected for maternal effects. Even though CE is routinely analyzed, no study has evaluated transformed CE scores with 2

  7. The Effect of Selected Factors on the Growth Ability of Charolais Cattle

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    Renáta Toušová

    2014-01-01

    Full Text Available The aim of this work was to analyze the growth abilities of bull and heifer calves (n = 190 of the Charolais breed calved in one herd from 2006 to 2011. The evaluation was carried out during the period of calf raising, focusing to the effects of sex, parity and the mating method on live birth weight (BLW and the live weight at 120 (LW120, 210 (LW210 and 365 (LW365 days of life, as well as the average daily weight gain reached by the age of 120 (G120, 210 (G210, and 365 (G365 days. Statistical analysis was carried out with the use of the SAS 9.3 program. The effect of sex on the live weight and average daily weight gain was statistically significant on the level of P < 0.01 always in favour of the bull calves (BLW +3.05 kg, LW120 +29.35 kg, LW210 +36.98 kg, and LW365 +117.23 kg. The lowest live birth weight was detected in the calves of primiparous cows (BLW = 45.46 kg; P < 0.01. The higher parity, the higher live birth weight was determined, with maximum values in cows from the fourth calving. The trends were similar in live weight at 120, 210 and 365 days of age, when significance level was P < 0.05. The parity effect on the average daily weight gain (G120, G210 a G365 was statistically insignificant (P > 0.05. The effect of embryo transfer (ET and other commonly used reproduction methods (insemination and natural mating, AI/PP was evaluated as well as. The calves born after embryo transfer showed a significantly (P < 0.01 higher the live birth weight as well as weight at different ages (BLW +5.85 kg, LW120 +18.15 kg, LW210 +22.94 kg and LW365 +35.43 kg, and G120 only (+100 g×day−1; P < 0.05. These results pointed the suitability of using the biotechnological reproduction methods, especially in relation to the total weight of the reared and fattened animals.

  8. ASSESSMENT OF CHAROLAIS BULLS POPULATION STRUCTURE BASED ON SNPs ANALYSES

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    Nina Moravčíková

    2014-02-01

    Full Text Available The aim of this study was identification of SNPs in leptin (LEP, leptin receptor (LEPR, growth hormone (GH and specific pituitary transcription factor (Pit-1 genes in order to analyze genetic structure of Charolais bulls’ population. The total numbers of genomic DNA samples were taken from 52 breeding bulls and analyzed by PCR-RFLP method. After digestion with restriction enzymes were detected in bulls’ population alleles with frequency: LEP/Sau3AI A 0.83 and B 0.17 (±0.037; LEPR/BseGI C 0.95 and T 0.05 (±0.021, GH/AluI L 0.62 and V 0.38 (±0.048 and Pit1/HinfI A 0.40 and B 0.60 (±0.048. Based on the observed vs. expected genotypes frequencies population across loci were in Hardy-Weinberg equilibrium (P>0.05, only in case of Pit-1 locus was detected disequilibrium. Predominant were in analyzed breeding bulls LEP/Sau3AIAA (0.69, LEPR/T945MCC (0.90, GH/AluILL (0.43 and Pit-1/HinfIAB (0.65 genotypes. The observed heterozygosity of SNPs was also transferred to the low (LEP/Sau3AI/0.248 and LEPR/T945M/0.088 or median polymorphic information content (GH/AluI/0.366 and Pit-1/HinfI/0.370. Within genetic variability estimating negative (LEPR/T945M and Pit-1/HinfI and positive values (LEP/Sau3AI and GH/AluI of fixation indexes FIS indicating slight heterozygote excess or deficiency based on analyzed genetic marker were observed.

  9. Pension funds' herding

    NARCIS (Netherlands)

    Broeders, D.; Chen, D.; Minderhoud, P.; Schudel, W.

    2016-01-01

    This paper uses unique and detailed transaction data to analyse herding behavior among pension funds. We distinguish between weak, semi strong and strong herding behaviour. Weak herding occurs if pension funds have similar rebalancing strategies. Semi strong herding arises when pension funds react s

  10. Relationship of lactate dehydrogenase activity with body measeurements of Angus x Charolais cows and calves

    Science.gov (United States)

    Angus x Charolais cows (n = 87) and their Angus-sired, spring-born calves (n = 86) were utilized to examine relationships between lactate dehydrogenase (LDH) activity and body measurements of beef cows; and the relationship between maternal LDH activity in late gestation and subsequent calf birth we...

  11. Mentasta Caribou Herd

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Mentasta caribou herd is located in southeast mainland Alaska and Western Yukonn Territory. This small herd has declined from a high Of approximately 3,100...

  12. Milk composition and its relationship with weaning weight in Charolais catte

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    Víctor Inocencio Pacheco Contreras

    2015-06-01

    Full Text Available To determine the effects of a number of non-genetic factors on milk components and estimate their indirect relationships with weaning weight (WW205, the percentages of protein, fat, lactose and solids non-fat in Charolais cows from Mexico were estimated. Lactation period (LP and calving season (CS had significant effects on protein and fat, whereas lactose and solids non-fat were only affected by the LP. Sire line and age of the dam had significant effects on calf birth weight, while CS affected WW205. Residual correlations between milk components and WW205 suggest a low but significant correlation with lactose. These results demonstrate the importance of several non-genetic factors on the composition of milk from Charolais cows managed under extensive cow-calf production systems and the indirect relationships between these factors and the weaning weight of a calf.

  13. Age of dam and sex of calf adjustments and genetic parameters for gestation length in Charolais cattle.

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    Crews, D H

    2006-01-01

    To estimate adjustment factors and genetic parameters for gestation length (GES), AI and calving date records (n = 40,356) were extracted from the Canadian Charolais Association field database. The average time from AI to calving date was 285.2 d (SD = 4.49 d) and ranged from 274 to 296 d. Fixed effects were sex of calf, age of dam (2, 3, 4, 5 to 10, > or = 11 yr), and gestation contemporary group (year of birth x herd of origin). Variance components were estimated using REML and 4 animal models (n = 84,332) containing from 0 to 3 random maternal effects. Model 1 (M1) contained only direct genetic effects. Model 2 (M2) was G1 plus maternal genetic effects with the direct x maternal genetic covariance constrained to zero, and model 3 (M3) was G2 without the covariance constraint. Model 4 (M4) extended G3 to include a random maternal permanent environmental effect. Direct heritability estimates were high and similar among all models (0.61 to 0.64), and maternal heritability estimates were low, ranging from 0.01 (M2) to 0.09 (M3). Likelihood ratio tests and parameter estimates suggested that M4 was the most appropriate (P or = 11-yr-old cows, respectively. Bivariate animal models were used to estimate genetic parameters for GES with birth and adjusted 205-d weaning weights, and postweaning gain. Direct GES was positively correlated with direct birth weight (BWT; 0.34 +/- 0.04) but negatively correlated with maternal BWT (-0.20 +/- 0.07). Maternal GES had a low, negative genetic correlation with direct BWT (-0.15 +/- 0.05) but a high and positive genetic correlation with maternal BWT (0.62 +/- 0.07). Generally, GES had near-zero genetic correlations with direct and maternal weaning weights. Results suggest that important genetic associations exist for GES with BWT, but genetic correlations with weaning weight and postweaning gain were less important.

  14. Accuracy of predicting genomic breeding values for carcass merit traits in Angus and Charolais beef cattle.

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    Chen, L; Vinsky, M; Li, C

    2015-02-01

    Accuracy of predicting genomic breeding values for carcass merit traits including hot carcass weight, longissimus muscle area (REA), carcass average backfat thickness (AFAT), lean meat yield (LMY) and carcass marbling score (CMAR) was evaluated based on 543 Angus and 400 Charolais steers genotyped on the Illumina BovineSNP50 Beadchip. For the genomic prediction within Angus, the average accuracy was 0.35 with a range from 0.32 (LMY) to 0.37 (CMAR) across different training/validation data-splitting strategies and statistical methods. The within-breed genomic prediction for Charolais yielded an average accuracy of 0.36 with a range from 0.24 (REA) to 0.46 (AFAT). The across-breed prediction had the lowest accuracy, which was on average near zero. When the data from the two breeds were combined to predict the breeding values of either breed, the prediction accuracy averaged 0.35 for Angus with a range from 0.33 (REA) to 0.39 (CMAR) and averaged 0.33 for Charolais with a range from 0.18 (REA) to 0.46 (AFAT). The prediction accuracy was slightly higher on average when the data were split by animal's birth year than when the data were split by sire family. These results demonstrate that the genetic relationship or relatedness of selection candidates with the training population has a great impact on the accuracy of predicting genomic breeding values under the density of the marker panel used in this study. © 2014 Her Majesty the Queen in Right of Canada. Animal Genetics © 2014 Stichting International Foundation for Animal Genetics.

  15. Vaccine herd effect.

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    Kim, Tae Hyong; Johnstone, Jennie; Loeb, Mark

    2011-09-01

    Vaccination ideally protects susceptible populations at high risk for complications of the infection. However, vaccines for these subgroups do not always provide sufficient effectiveness. The herd effect or herd immunity is an attractive way to extend vaccine benefits beyond the directly targeted population. It refers to the indirect protection of unvaccinated persons, whereby an increase in the prevalence of immunity by the vaccine prevents circulation of infectious agents in susceptible populations. The herd effect has had a major impact in the eradication of smallpox, has reduced transmission of pertussis, and protects against influenza and pneumococcal disease. A high uptake of vaccines is generally needed for success. In this paper we aim to provide an update review on the herd effect, focusing on the clinical benefit, by reviewing data for specific vaccines.

  16. Herd-level risk factors for antimicrobial demanding gastrointestinal diseases in Danish herds with finisher pigs

    DEFF Research Database (Denmark)

    Hybschmann, G. K.; Ersbøll, A.K.; Vigre, Håkan

    2011-01-01

    quarter per herd. Three potential herd-level risk factors were evaluated: herd size (number of finishers delivered for slaughter); herd health status (herds in the Specific Pathogen Free (SPF) System, conventional herds); and herd type (herds including only finishers, integrated herds). Data were analyzed...... using general linear mixed models with repeated measurements. Smaller herds had a larger AMU per finisher than larger herds. Integrated herds had lower AMU as compared with herds with only finishers. Herds within the SPF System had a larger decrease in AMU with increasing herd size compared...

  17. MEAT QUALITY FROM CHAROLAIS BULLS FED DIETS WITH DIFFERENT LEVELS OF CORN SILAGE INCLUSION

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    G. Cozzi

    2007-06-01

    Full Text Available A sample of 6 intensive beef farms was selected according to the feeding plan adopted during the fattening period of Charolais bulls. Two farms did not include any corn silage in the diet (CS0, while corn silage represented 22% of the dietary DM in the second group of 2 farms (CS22, and it raised up to 44% of the dietary DM in the last 2 farms (CS44. Five bulls were randomly selected from each farm to be slaughtered in the same abattoir. Bulls age was similar across treatments but the CS44 bulls had a lower carcass weight (396 kg than the other two treatments (436 and 446 kg for CS0 and CS22, respectively. Carcass fleshiness (SEUROP and fatness scores were not affected by the level of corn silage in the diet. Meat quality was evaluated on a joint sample of the m. Longissimus thoracis, excised from the 5th to the 9th rib of each right half carcass 24 h post-mortem, after an ageing period of 10 d vacuum packaged at 4°C. Meat chemical analysis showed no variations in pH, DM, intramuscular fat and protein content due to the different silage inclusion in the diet. Only the cholesterol content was progressively reduced in the meat of bulls fed increasing quantities of corn silage according to a significant negative linear trend. Meat colour, cooking losses and shear force values were not affected by the diet. Therefore, based on these findings there are no substantial arguments against the use of a large amount of corn silage in the fattening diets of Charolais bulls.

  18. Indirect effects by meningococcal vaccines: herd protection versus herd immunity.

    Science.gov (United States)

    Bröker, Michael

    2011-08-01

    The term "herd immunity" for the indirect effect of meningococcal conjugate vaccines is inaccurate. A more appropriate term is "herd protection," because this term correctly describes the public effects imparted by vaccination campaigns against the meningococcus.

  19. Understanding Herd Immunity.

    Science.gov (United States)

    Metcalf, C J E; Ferrari, M; Graham, A L; Grenfell, B T

    2015-12-01

    Individual immunity is a powerful force affecting host health and pathogen evolution. Importantly, the effects of individual immunity also scale up to affect pathogen transmission dynamics and the success of vaccination campaigns for entire host populations. Population-scale immunity is often termed 'herd immunity'. Here we outline how individual immunity maps to population outcomes and discuss implications for control of infectious diseases. Particular immunological characteristics may be more or less likely to result in a population level signature of herd immunity; we detail this and also discuss other population-level outcomes that might emerge from individual-level immunity.

  20. Risk factors for brucellosis seropositivity of goat herds in the Mexicali Valley of Baja California, Mexico.

    Science.gov (United States)

    Mikolon, A B; Gardner, I A; Hernandez De Anda, J; Hietala, S K

    1998-12-01

    A case-control study was conducted in the Mexicali Valley to identify risk factors for goat-herd seropositivity for Brucella melitensis. Nineteen case herds (> or = 2 positive results with the 8% rose bengal plate test (RBT)) and 55 control herds (zero positive results in RBT), matched for herdsize and geographic location, were enrolled. Conditional logistic regression was used to construct a multivariable model of the odds of seropositivity using variables assessed in a questionnaire administered to goat ranchers. The final model for herd seropositivity included increased risk from importation of goats from other Mexican states, the presence of La Mancha breed does, and the presence of does born outside the herd. Increasing herdsize was also highly significant (p < 0.01). In addition, a significant (p < 0.05) positive association was found between the presence of seropositive dogs (as assessed by RBT) and seropositive goats on the same ranch.

  1. Online Anti-Brand Herds

    DEFF Research Database (Denmark)

    Langley, David J.; Tan, Chee-Wee; Worm, Daniël

    the Netherlands, we develop an analytical model to investigate drivers of herd formation, growth, and dissolution. Finally, combining environmental turbulence literature with our empirical findings, we derive a novel typology of online anti-brand herd behaviors, and put forward six propositions to guide theory...... light on the formation, growth, and dissolution of online anti-brand herds. First we expand on the concept of environmental turbulence to advance core properties unique to online herd behavior. Next, based on evidence gathered from 40 online anti-brand herd episodes targeting two prominent firms from...

  2. Phenotypic and genetic relationships of feed efficiency with growth performance, ultrasound, and carcass merit traits in Angus and Charolais steers.

    Science.gov (United States)

    Mao, F; Chen, L; Vinsky, M; Okine, E; Wang, Z; Basarab, J; Crews, D H; Li, C

    2013-05-01

    Feed efficiency is of particular importance to the beef industry, as feed costs represent the single largest variable cost in beef production systems. Selection for more efficient cattle will lead to reduction of feed related costs, but should not have adverse impacts on quality of the carcass. In this study, we evaluated phenotypic and genetic correlations of residual feed intake (RFI), RFI adjusted for end-of-test ultrasound backfat thickness (RFIf), and RFI adjusted for ultrasound backfat thickness and LM area (RFIfr) with growth, ultrasound, and carcass merit traits in an Angus population of 551 steers and in a Charolais population of 417 steers. In the Angus steer population, the phenotypic and genetic correlation of RFI with carcass merit traits including HCW, carcass backfat, carcass LM area, lean meat yield, and carcass marbling were not significant or weak with correlations coefficients ranging from -0.0007 ± 0.05 to 0.18 ± 0.21. In the Charolais steer population, the phenotypic and genetic correlations of RFI with the carcass merit traits were also weak, with correlation coefficients ranging from -0.07 ± 0.06 to 0.19 ± 0.18, except for the genetic correlation with carcass average backfat, which was moderate with a magnitude of 0.42 ± 0.29. Inclusion of ultrasound backfat thickness in the model to predict the expected daily DMI for maintenance explained on average an additional 0.5% variation of DMI in the Angus steers and 2.3% variation of DMI in the Charolais steer population. Inclusion of both the ultrasound backfat and LM area in the model explained only 0.7% additional variance in DMI in the Angus steer population and only 0.6% in the Charolais steer population on top of the RFIf model. We concluded that RFIf adjusted for ultrasound backfat at the end of the test will lead to decreases of both the phenotypic and genetic correlations with carcass backfat and marbling score to a greater extent for late-maturing beef breeds such as Charolais than

  3. Online Anti-Brand Herds

    DEFF Research Database (Denmark)

    Langley, David J.; Tan, Chee-Wee; Worm, Daniël

    light on the formation, growth, and dissolution of online anti-brand herds. First we expand on the concept of environmental turbulence to advance core properties unique to online herd behavior. Next, based on evidence gathered from 40 online anti-brand herd episodes targeting two prominent firms from...... the Netherlands, we develop an analytical model to investigate drivers of herd formation, growth, and dissolution. Finally, combining environmental turbulence literature with our empirical findings, we derive a novel typology of online anti-brand herd behaviors, and put forward six propositions to guide theory......The online environment offers a fertile breeding ground for anti-brand herds of disgruntled consumers. Firms are often caught off guard by the unpredictability of such herds and, as a consequence, are forced into a reactive, defensive stance. We conduct a social media analysis that aims to shed...

  4. HIPOPLASIA CEREBELAR E PORENCEFALIA EM BOVINOS CHAROLÊS NO SUL DO RIO GRANDE DO SUL CEREBELLAR HYPOPLASIA AND PORENCEPHALY IN CHAROLAIS CATLLE IN SOUTHERN BRAZIL

    Directory of Open Access Journals (Sweden)

    Ana Lucia Schild

    2001-02-01

    Full Text Available Descrevem-se dois casos de hipoplasia cerebelar congênita observados em terneiros da raça Charolês, pertencentes a um estabelecimento localizado no município de Capão do Leão. Um dos animais apresentava sinais clínicos cerebelares ao nascimento, caracterizados por severa incoordenação motora, hipermetria e tremores de intenção, principalmente da cabeça e do pescoço. O outro animal não conseguia manter-se em estação e apresentava opistótono acentuado. As lesões macroscópicas caracterizaram-se por hipoplasia cerebelar, observando-se apenas remanescentes das regiões do flóculo e do paraflóculo cerebelares e uma cavidade preenchida por líquido e recoberta pelas leptomeninges, que estavam aderidas aos resquícios das folhas cerebelares. Ao corte do encéfalo, havia hidrocefalia discreta e a presença de cavidades císticas (porencefalia. São discutidas as possíveis etiologias, sugerindo-se a possibilidade de que a enfermidade tenha sido causada pelo vírus da diarréia viral bovina-doença das mucosas, apesar dos resultados negativos da imuno-histoquímica realizada em fragmentos do cerebelo dos animais doentes para detecção desse vírus.Two cases of cerebellar hypoplasia in Charolais calves from a herd of a farm located in the municipality of Capão do Leão, Southern Brazil are described. One calf with cerebellar clinical signs at birth, showed incoordination, hypermetria and intention tremors, mainly in the neck and head. The other calf was recumbent with opisthotonos. The gross lesions were characterized by cerebellar hypoplasia, with only remnants of cerebellar floculus and parafloculus and an expanded fluid-filled space covered by leptomeninges. Mild hydrocephalus and porencephaly were observed in the cerebrum. It was discussed the possible etiologies and suggested the possibility of the disease has been caused by bovine viral diarrhea-mucosal disease (BVD-MD virus despite of negative results of imuno

  5. Prevalence of VTEC O157 in dairy and veal herds and risk factors for veal herds

    NARCIS (Netherlands)

    Berends, I.M.G.A.; Graat, E.A.M.; Swart, W.A.J.M.; Weber, M.F.; Giessen, van de A.W.; Lam, T.J.G.M.; Heuvelink, A.E.; Weering, H.J.

    2008-01-01

    The aim of this study was to determine the herd prevalence of veal and dairy herds and to identify risk factors for VTEC O157 positive veal herds. The study was based on monitoring data from November 1996 through July 2005 of 1051 dairy herds and 930 veal herds. The herd level prevalence (95% CI) wa

  6. Loci asociados con enfermedades genéticas y calidad de carne en bovinos Charolais Mexicanos

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    Ana María Sifuentes Rincón

    2015-01-01

    Full Text Available Se determinaron las frecuencias alélicas y genotípicas de ocho marcadores localizados en los genes calpaína (CAPN, 4 751 y 316, calpastatina (CASTT1 y tiroglobulina (TG5, asociados a calidad de carne, y en los genes, m iost atina (MSTN, Q204X, arginino succinato sintasa (ASS, monofosfato sintasa (UMPS y miofosforilasa (PYGM, asocia dos a enfermedade s genéticas de ganado bovino. Se muestrearon 493 animales Charolais de registro de dos hatos ubicado s en Sonora (n=157 y tres en Nuevo León (n=336. No se encontraron portadores de los alelos T-ASS y T-UM PS, pero sí portadores del alelo Q204X del gen MSTN en frecuencias de  1 % en las poblaciones de Sonora y de 8.6 a 14.4 % en las de Nuevo León. Además, se identificaron portadores del marcador del gen PYGM, en frecuencias del 6.5 y de 1.0 % para un hato de Sonora y otro de Nuevo León, respectivamente. El análisis de diferenciación génica p areado entre las poblaciones y con los cuatro loci mostró que hay diferencias altamente significativas dentro de pobl aciones del noroeste ( P <0.0001 y entre éstas y las del noreste ( P <0.001, la cual es explicada principalmente por los loci CAPN-316 y TG5. De acuerdo a los resultados obtenidos se recomienda el monitoreo del marcador del gen PYGM y del ale lo Q204X del gen MSTN, así como también implementar estrategias para confirmar la utilidad de los marcadores asociado s a calidad y productividad como herramienta para complementar los progra mas de mejoramiento genético.

  7. Herd immunity and herd effect: new insights and definitions.

    Science.gov (United States)

    John, T J; Samuel, R

    2000-01-01

    The term herd immunity has been used by various authors to conform to different definitions. Earlier this situation had been identified but not corrected. We propose that it should have precise meaning for which purpose a new definition is offered: "the proportion of subjects with immunity in a given population". This definition dissociates herd immunity from the indirect protection observed in the unimmunised segment of a population in which a large proportion is immunised, for which the term 'herd effect' is proposed. It is defined as: "the reduction of infection or disease in the unimmunised segment as a result of immunising a proportion of the population". Herd immunity can be measured by testing a sample of the population for the presence of the chosen immune parameter. Herd effect can be measured by quantifying the decline in incidence in the unimmunised segment of a population in which an immunisation programme is instituted. Herd immunity applies to immunisation or infection, human to human transmitted or otherwise. On the other hand, herd effect applies to immunisation or other health interventions which reduce the probability of transmission, confined to infections transmitted human to human, directly or via vector. The induced herd immunity of a given vaccine exhibits geographic variation as it depends upon coverage and efficacy of the vaccine, both of which can vary geographically. Herd effect is determined by herd immunity as well as the force of transmission of the corresponding infection. Clear understanding of these phenomena and their relationships will help improve the design of effective and efficient immunisation programmes aimed at control, elimination or eradication of vaccine preventable infectious diseases.

  8. Análise produtiva da utilização de touros BBB e Charoleses em vacadas comerciais Charolais and BBB bulls at suckling cow herds

    Directory of Open Access Journals (Sweden)

    A. Perdigão

    2007-01-01

    Full Text Available O Branco Azul Belga (BBB é uma raça bovina para cruzamentos terminais que, através de exposição em feiras, tem vindo a tentar convencer os criadores nacionais do seu interesse. Estamos como é lógico perante um efeito de marketing! Este trabalho pretende demonstrar, como contributo, o que realmente acontece quando utilizamos os touros BBB (via inseminação artificial, comparativamente com os touros de raça Charolesa, em termos de resposta reprodutiva e produtiva. Foi interessante o incremento de peso desmamado (+15%, assim como a quase inexistência de distócias (vacas todas multíparas. No entanto, a nível da inseminação artificial como instrumento zootécnico, temos de focar o incremento das dificuldades de maneio, que podem desencorajar os criadores, para a respectiva utilização.The Belgian Blue White (BBB, is a beef cattle breed for terminal crossings that have come, through exposition in fairs, trying to convince the national cattleman about its interest. We are as it is logical before a marketing effect! This work intends to demonstrate, as contribution, what really happens when we use BBB bulls (by artificial insemination, still compared with the bulls of Charolesa breed, in terms of reproductive and productive reply. The increment of weaned weight through BBB was interesting (+15%, as well as almost the inexistence of distocia (all mature cows. However, about the artificial insemination, as a livestock instrument, we have to point out the increment of the difficulties of management that can discourage the producers, for the use of the BBB breed.

  9. Análise produtiva da utilização de touros BBB e Charoleses em vacadas comerciais Charolais and BBB bulls at suckling cow herds

    OpenAIRE

    2007-01-01

    O Branco Azul Belga (BBB) é uma raça bovina para cruzamentos terminais que, através de exposição em feiras, tem vindo a tentar convencer os criadores nacionais do seu interesse. Estamos como é lógico perante um efeito de marketing! Este trabalho pretende demonstrar, como contributo, o que realmente acontece quando utilizamos os touros BBB (via inseminação artificial), comparativamente com os touros de raça Charolesa, em termos de resposta reprodutiva e produtiva. Foi interessante o incremento...

  10. Effect of region, herd size, and milk production on reasons cows leave the herd.

    Science.gov (United States)

    Smith, J W; Ely, L O; Chapa, A M

    2000-12-01

    Dairy Herd Improvement Holstein herd summary records (n = 11,259) were obtained for the year ending 1998. Reasons cows reportedly left the herd based on termination codes were analyzed for the effect of region, herd size, and herd milk production level. Regions were: North, Midsouth, and South. Herd sizes were: small (25 to 99), low medium (100 to 149), high medium (150 to 299), and large (greater than or equal to 300 cows). Milk production levels were: low (less than 7258 kg), medium (7258 to 9072 kg), and high (greater than 9072 kg). The overall percentage of cows leaving the herd was higher in the Midsouth than the South and increased with herd size. Low producing herds reported a lower percentage of cows left than high producing herds. Herds in the South reported more cows leaving for reproduction, death, and low production and fewer leaving for mastitis. Herds in the North and Midsouth reported more cows leaving for injury/other and disease, respectively. Cows left herds for disease less frequently in the North. Large herds in the South had a higher percentage leaving for low production than any herd size group in the North. Small herds reported more cows leaving for reproduction and mastitis than high medium and low medium size herds. The percentage of cows leaving for feet and leg problems was lowest for small size herds. High producing herds reported more cows leaving for reproduction, mastitis, feet and legs and disease.

  11. Behavior patterns of cows with Charolais or Nellore breed predominance fed diets with plant extract or monensin sodium

    Directory of Open Access Journals (Sweden)

    Luciane Rumpel Segabinazzi

    2011-12-01

    Full Text Available The objective of this research was to study the ingestive behavior of feedlot cows fed additives based on plant extracts or monensin sodium. Twenty-four Charolais and Nellore crossbred cows with age and average initial weight of 7 years and 423 kg, respectively, were used. The experimental diets were plant extracts: basal diet + 5 g/animal/day of a natural additive composed of 750 mg of essential oil of thyme (Thymus vulgaris, 150 mg of garlic (Allium sativum, 250 mg of rosemary extract (Rosmarimus officinalis, 250 mg of canola oil (Brassica napus, 250 mg extract of quillaja (Quillaja saponaria, and 3350 mg of corn starch; sodium monensin: basal diet + 300 mg/monensin/animal/day; and control: basal diet without additive. The basal diet contained sorghum silage and concentrate in a 62:38 ratio. The experimental design was completely randomized with a 3 × 2 (3 diets and 2 breed predominances factorial arrangement, and means were compared using DMS test at 5% of significance. The type of additive consumed did not alter animal feeding behavior. Cows with Charolais predominance consumed more dry matter (13.78 vs. 12.38 kg/day and neutral detergent fiber (7.81 vs. 6.89 kg/day, ruminated for longer (8.47 vs. 7.82 h, spent more time chewing (13.05 vs 12.01 h, had a greater number of chews per minute (58.88 vs 53.21 and a greater number of ruminal bolus (541.43 vs. 464.09 boluses/day; however, cows with Nellore predominance had greater idling time (11.82 vs. 10.74 h.

  12. INFORMATION ASYMMETRY AND HERDING BEHAVIOR

    Directory of Open Access Journals (Sweden)

    Puput Tri Komalasari

    2016-06-01

    Full Text Available Conceptually, the stock market is strong form efficient in the long term. However, in practice, there are various forms of market anomalies that undermine the accuracy of the efficient market hypothesis. One factor suspected as the cause of market inefficiency is herding behavior. Investors herd when they imitate the actions of other investors. This behavior occurs when there is a continuous interaction among rational investors that prevents them from seeking information about market fundamentals. This study provides new insights by including information asymmetry as a moderating variable. This research examines the phenomenon of herding behavior in the Indonesia Stock Exchange as well as examines directly the effect of information asymmetry on herding behavior. The period of study is 2008 using time series of daily stocks data that actively traded in the capital market. Results of this study find that investor tends to follow market consensus when price changes at the low level, but when there is large price swing market participant acts independently from other investors. Interestingly, this study finds that information asymmetry is a necessary condition for the existence of herding behavior.

  13. "Herd immunity": a rough guide.

    Science.gov (United States)

    Fine, Paul; Eames, Ken; Heymann, David L

    2011-04-01

    The term "herd immunity" is widely used but carries a variety of meanings. Some authors use it to describe the proportion immune among individuals in a population. Others use it with reference to a particular threshold proportion of immune individuals that should lead to a decline in incidence of infection. Still others use it to refer to a pattern of immunity that should protect a population from invasion of a new infection. A common implication of the term is that the risk of infection among susceptible individuals in a population is reduced by the presence and proximity of immune individuals (this is sometimes referred to as "indirect protection" or a "herd effect"). We provide brief historical, epidemiologic, theoretical, and pragmatic public health perspectives on this concept.

  14. Herd Immunity: A Brief Review.

    Science.gov (United States)

    Alam, M J; Rahman, M F

    2016-04-01

    Immunization is a means of protecting the greatest number of people. By reducing the number of susceptible in the community, it augments "herd immunity" making the infection more difficult to spread. It also reduces the risk for those individuals who have escaped vaccination or those who have not developed satisfactory protection. It is well to bear in mind that immunizations are not at all 100 per cent effective, particularly when an individual is exposed to a large dose of pathogenic organisms.

  15. Control of Yersinia enterocolitica in pigs at herd level

    DEFF Research Database (Denmark)

    Skjerve, Eystein; Lium, Bjørn; Nielsen, Bent

    1998-01-01

    A higher herd prevalence of antibodies (ELISA) to Yersinia enterocolitica O:3 was found in conventional slaughter production (86.0% seropositive herds) than in conventional farrow-to-finish herds (53.1% seropositive herds). The herd prevalence of antibodies to Y. enterocolitica in multiplying herds.......41) and using straw bedding for slaughter pigs (OR = 2.25) were other factors that increased the risk. In conclusion, the epidemiological data suggest that it is possible to reduce the herd prevalence of Yersinia enterocolitica O:3 by minimising contact between infected herds and non-infected herds. Further...

  16. Biosecurity in 121 Danish sow herds

    DEFF Research Database (Denmark)

    Boklund, Anette; Mortensen, Sten; Houe, H.

    2003-01-01

    questions. The 121 units were situated in three areas with different swine densities. Sow units were described by their sizes (units with >110 sows were regarded as large herds) and health status (SPF herds or conventional herds). Of the 121 sow herds, 63 (52%) sold weaners. Most sow units (71%) used...... to be cleaned (16%) or cleaned and disinfected (48%) before the transport; large sites and SPF sites more often required stricter biosecurity measures, for example a quarantine period before the transport of weaners....

  17. Herd-level risk factors for subclinical Salmonella infection in European finishing-pig herds

    DEFF Research Database (Denmark)

    Wong, Danilo Lo Fo; Dahl, J.; Stege, H.

    2004-01-01

    . Pigs produced in batches in herds with hygienic-lock facilities had >3-times lower odds for testing seropositive compared to pigs in herds where only one or neither factor was present. In herds where the caretaker(s) washed hands consistently before tending to the animals, pigs had 1.5-times lower odds...

  18. Phenotypic and genetic relationships of feeding behavior with feed intake, growth performance, feed efficiency, and carcass merit traits in Angus and Charolais steers.

    Science.gov (United States)

    Chen, L; Mao, F; Crews, D H; Vinsky, M; Li, C

    2014-03-01

    Feeding behavior traits including daily feeding duration (FD), daily feeding head down time (HD), average feeding duration per feeding event (FD_AVE), average feeding head down time per feeding event (HD_AVE), feeding frequency (FF), and meal eating rate (ER) were analyzed to estimate their phenotypic and genetic correlations with feed intake, growth performance, residual feed intake (RFI), ultrasound, and carcass merit traits in Angus and Charolais finishing steers. Heritability estimates for FD, HD, FD_AVE, HD_AVE, FF, and ER were 0.27 ± 0.09 (SE), 0.25 ± 0.09, 0.19 ± 0.06, 0.11 ± 0.05, 0.24 ± 0.08, and 0.38 ± 0.10, respectively, in the Angus population and 0.49 ± 0.12, 0.38 ± 0.11, 0.31 ± 0.09, 0.29 ± 0.10, 0.43 ± 0.11, and 0.56 ± 0.13, respectively, in the Charolais population. In both the Angus and Charolais steer populations, FD and HD had relatively stronger phenotypic (0.17 ± 0.06 to 0.32 ± 0.04) and genetic (0.29 ± 0.17 to 0.54 ± 0.18) correlations with RFI in comparison to other feeding behavior traits investigated, suggesting the potential of FD and HD as indicators in assessing variation of RFI. In general, feeding behavior traits had weak phenotypic correlations with most of the ultrasound and carcass merit traits; however, estimated genetic correlations of the feeding behavior traits with some fat deposition related traits were moderate to moderately strong but differed in magnitude or sign between the Angus and Charolais steer populations, likely reflecting their different biological types. Genetic parameter estimation studies involving feeding behavior traits in beef cattle are lacking and more research is needed to better characterize the relationships between feeding behavior and feed intake, growth, feed utilization, and carcass merit traits, in particular with respect to different biological types of cattle.

  19. Biosecurity in 121 Danish sow herds

    DEFF Research Database (Denmark)

    Boklund, Anette; Mortensen, Sten; Houe, H.

    2003-01-01

    Herds are under constant risk of introducing new pathogens from different sources. In this article we describe biosecurity practices in Danish sow herds. Between December 1, 1999 and February 29, 2000, 121 sow units were interviewed regarding biosecurity on the site. The questionnaire contained 6...

  20. Forecasting metal prices: Do forecasters herd?

    DEFF Research Database (Denmark)

    Pierdzioch, C.; Rulke, J. C.; Stadtmann, G.

    2013-01-01

    We analyze more than 20,000 forecasts of nine metal prices at four different forecast horizons. We document that forecasts are heterogeneous and report that anti-herding appears to be a source of this heterogeneity. Forecaster anti-herding reflects strategic interactions among forecasters...

  1. Herd- and sow-related risk factors for lameness in organic and conventional sow herds

    DEFF Research Database (Denmark)

    Knage-Rasmussen, Kristian Møllegaard; Houe, Hans; Rousing, Tine;

    2014-01-01

    Lameness in sows is an animal welfare problem which also presents an economic challenge to pig producers. Information about the prevalence of herd lameness in organic sows is relatively scarce. The first objective of this study was to establish the prevalence of lameness and to identify risk...... and fifty four gestation sows from 44 indoor conventional and nine organic sow herds were included in this study. The nine organic herds were visited twice: once in summer/autumn 2011, and once in winter/spring 2012. In winter/spring 2011, a total of 44 indoor conventional herds were visited. Risk factors...... assigned scores for lameness, body condition and bursitis. A multivariable analysis was carried out by logistic regression with the herd and observer as random effects. The average herd lameness prevalence in gestation and lactation sows in organic herds was 11% in summer/autumn and 4.6% in winter...

  2. My Mexican Friend Chabolla

    Institute of Scientific and Technical Information of China (English)

    MiLan

    2005-01-01

    Chabolla is a Mexican learning Chinese from me. His Chinese name is Xia Boyang, pronounced similarly with his Mexican surname. On one occasion,I told him that “Xia Boyang” is a translated name of the hero in a Russian novel, he felt quite surprised and said seriously to me, “I am not Russian. I am Mexican.”

  3. Mexican Parenting Questionnaire (MPQ)

    Science.gov (United States)

    Halgunseth, Linda C.; Ispa, Jean M.

    2012-01-01

    The present study was conducted in four phases and constructed a self-report parenting instrument for use with Mexican immigrant mothers of children aged 6 to 10. The 14-item measure was based on semistructured qualitative interviews with Mexican immigrant mothers (N = 10), was refined by a focus group of Mexican immigrant mothers (N = 5), and was…

  4. Herd immunity: recent uses in vaccine assessment.

    Science.gov (United States)

    Gonçalves, Guilherme

    2008-12-01

    Human communities defend themselves against specific infectious agents in a way that extends beyond the simple sum of the immune status of its individuals. By analogy with individual immunity to specific agents, the community level of immunity may vary from complete susceptibility to full protection. Herd immunity has been used to name this community property, which is the result of evolution through natural selection, leading to relationships between two species, typical of prey-predator systems. Varying uses of the term herd immunity led to the use of other expressions, such as herd protection, herd effect and community immunity. Knowledge derived from observational studies and models on herd immunity has supported decisions on the choice of vaccines and vaccination strategies for the benefit of populations. This knowledge is most likely to be extended in the future, with far-reaching effects.

  5. Molecular traceability of beef from synthetic Mexican bovine breeds.

    Science.gov (United States)

    Rodríguez-Ramírez, R; Arana, A; Alfonso, L; González-Córdova, A F; Torrescano, G; Guerrero Legarreta, I; Vallejo-Cordoba, B

    2011-10-06

    Traceability ensures a link between carcass, quarters or cuts of beef and the individual animal or the group of animals from which they are derived. Meat traceability is an essential tool for successful identification and recall of contaminated products from the market during a food crisis. Meat traceability is also extremely important for protection and value enhancement of good-quality brands. Molecular meat traceability would allow verification of conventional methods used for beef tracing in synthetic Mexican bovine breeds. We evaluated a set of 11 microsatellites for their ability to identify animals belonging to these synthetic breeds, Brangus and Charolais/Brahman (78 animals). Seven microsatellite markers allowed sample discrimination with a match probability, defined as the probability of finding two individuals sharing by chance the same genotypic profile, of 10(-8). The practical application of the marker set was evaluated by testing eight samples from carcasses and pieces of meat at the slaughterhouse and at the point of sale. The DNA profiles of the two samples obtained at these two different points in the production-commercialization chain always proved that they came from the same animal.

  6. On the surveillance for animal diseases in small herds

    DEFF Research Database (Denmark)

    Greiner, Matthias; Dekker, Aldo

    2005-01-01

    Small herds may present a problem in surveillance for infectious animal diseases because typical levels of a within-herd design prevalence are not directly applicable. We suggest a definition of small herds as those smaller than 2/(within-herd design prevalence) on the basis that such herds would...... be expected to have less than two (i.e. only one) infected animals. Consequently, the probability of detecting small herds cannot be improved by choosing a larger sample size within the herd. We derive necessary sample sizes of herds and the probability ("confidence") of detecting disease within a stratum...... of small herds, given the among-herd design prevalence and test diagnostic sensitivity. Both a binomial model and a Poisson model can be used to establish the confidence for a given sample size of herds (and vice versa). The results of a simulation study suggest that the Poisson model provides more...

  7. Ecology of the Porcupine caribou herd

    Directory of Open Access Journals (Sweden)

    Kenneth R. Whitten

    1996-01-01

    Full Text Available Researchers have described general patterns of population regulation that fit most caribou (Rangifer tarandus herds. Nevertheless, specific factors operating on particular populations vary greatly, and efforts to categorize herds according to the general patterns often lead to confusion. It is difficult for biologists to attempt to describe population dynamics in terms of density relationships for wide-ranging arctic caribou such as the Porcupine Herd. In these herds density varies as a function of dispersal and erratic movement patterns and is not simply the number of caribou divided by a fixed range area. Density is also a poor surrogate for resource availability per individual caribou because climatic factors affect forage and/or access to forage independendy of caribou numbers. Thus classic signs of nutritional stress such as delayed puberty, reduced productivity, and winter starvation can occur when a population is small as well as large and do not necessarily denote food competition brought on by high density, per se. Nutritional stress and exacerbated predation due to adverse weather conditions occasionally cause the Porcupine Herd to decline, and limiting factors such as poor nutrition, predation, harvest, accidents, and disease act in combination to keep herd growth rates low during periods of good weather. Adverse weather setbacks occur frequently, and the herd remains within a fairly restricted range of densities over long time periods. There is no true density dependent regulation and no equilibrium in this system.

  8. Gastrointestinal nematodes and anthelmintic resistance in Danish goat herds

    DEFF Research Database (Denmark)

    Holm, Signe A.; Sørensen, Camilla; Thamsborg, Stig M.

    2014-01-01

    The prevalence of gastrointestinal parasites in Danish goats and the presence of anthelmintic resistance (AR) in 10 selected herds were investigated during April-September 2012. All Danish herds (n = 137) with 10 or more adult goats were invited to participate, and of these 27 herds met......, resistance to the most commonly used anthelmintics is widespread in larger goat herds throughout Denmark....

  9. Herd size, distribution, harvest, management issues, and research priorities relevant to caribou herds in Alaska

    Directory of Open Access Journals (Sweden)

    Patrick Valkenburg

    1998-03-01

    Full Text Available There are presently about 960 000 caribou in 32 herds in Alaska, including 4 herds shared with Yukon and Northwest Territories. Since complete population data were last published in the mid-1980s, Alaska's caribou population has doubled in size, largely from increases in the Western Arctic and Mulchatna herds. The number of recognized herds has increased by 6, largely because of increased use of radiotelemetry to inventory small caribou herds in inaccessible areas, and transplanting caribou to unoccupied ranges. About 33 000 caribou are harvested annually in Alaska, mostly from the Western Arctic, Mulchatna, and Nelchina herds. The primary wildlife management problem in Alaska for caribou and other species is the lack of clear management authority among state and federal agencies. Research priorities include work on the influence of short-term and long-term weather trends on nutritional ecology of caribou, and predation mitigation including sterilization, translocation, and diversionary feeding of wolves during the caribou calving period.

  10. Forecasting Housing Approvals in Australia: Do Forecasters Herd?

    DEFF Research Database (Denmark)

    Stadtmann, Georg; Pierdzioch; Rülke

    2012-01-01

    Price trends in housing markets may reflect herding of market participants. A natural question is whether such herding, to the extent that it occurred, reflects herding in forecasts of professional forecasters. Using more than 6,000 forecasts of housing approvals for Australia, we did not find...... evidence of forecaster herding. On the contrary, forecasters anti-herd and, thereby, tend to intentionally scatter their forecasts around the consensus forecast. The extent of anti-herding seems to vary over time.We also found that more pronounced anti-herding leads to less accurate forecasts....

  11. Within-herd prevalence of Salmonella Dublin in endemically infected dairy herds

    DEFF Research Database (Denmark)

    Nielsen, Liza Rosenbaum

    2013-01-01

    SUMMARY In this study within-herd prevalence of Salmonella Dublin was investigated in three age groups (calves, young stock, adult cows) during five herd visits at 3-month intervals of 14 endemically infected dairy herds. A total of 10162 paired faecal cultures and antibody measurements were used...... stock and adult cows than in calves. Hierarchical mixed-model results showed that seroprevalence was associated with the bacteriological status in calves and cows, but not in young stock. These results can be used to develop and validate theoretical infection dynamics models and to design effective...... control programmes for Salmonella Dublin in dairy herds....

  12. The Porcupine herd of barren ground caribou

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers the porcupine herd of the barren ground caribou. The report covers the short history, the winter range, migration route, phenology, movements and...

  13. Herd behaviour, strategic complementarities and technology adoption

    OpenAIRE

    2004-01-01

    In technology adoption, herd behaviour can lead to a suboptimal outcome. An example is given by Choi (1997): it is a model of technology choice under uncertainty where herding arises because of strategic complementarities and risk aversion. It causes a positive experimenting bias against the adoption of a more efficient (in terms of expected value) technology. We introduce in his model an additional element upon which firms base their technology decision: the economic environment. We investig...

  14. Assessment of beef production from Brahman x Thai native and Charolais x Thai native crossbred bulls slaughtered at different weights. I: growth performance and carcass quality.

    Science.gov (United States)

    Waritthitham, A; Lambertz, C; Langholz, H-J; Wicke, M; Gauly, M

    2010-05-01

    Effects of genotype and slaughter weight on growth performance and carcass quality of Brahman x Thai native (BRA) and Charolais x Thai native (CHA) crossbred bulls were studied. Thirty-four BRA and 34 CHA bulls raised under practical fattening beef farm conditions were randomly selected and slaughtered at 500, 550 and 600 kg live weight, respectively. Parameters of growth performance, carcass quality and commercial prime cuts were determined. Results showed that growth performance and carcass quality of CHA was better, since they showed higher weight gain, better body muscle score, higher carcass weight high dressing percentage, higher carcass muscle, less carcass fat and bone plus connective tissue proportions, better carcass classifications, greater loin eye area and higher commercial prime cut percentage. Slaughter weights up to 600 kg resulted in increased carcass weight, loin eye area and percentage of commercial prime cuts and can therefore be recommended.

  15. Herd-level diagnosis for Salmonella enterica subsp enterica serovar Dublin infection in bovine dairy herds

    NARCIS (Netherlands)

    Veling, J.; Barkema, H.W.; Schans, van de J.; Zijderveld, van F.G.; Verhoeff, J.

    2002-01-01

    Herd-level sensitivities of bacteriological and serological methods were compared in 79 bovine dairy herds, recently infected with Salmonella enterica subsp. enterica serovar Dublin. All farms experienced clinical signs of salmonellosis for the first time and had no history of vaccination against sa

  16. Herd-level risk factors for subclinical Salmonella infection in European finishing-pig herds

    DEFF Research Database (Denmark)

    Wong, Danilo Lo Fo; Dahl, J.; Stege, H.

    2004-01-01

    Our objective was to find herd factors associated with pigs testing seropositive for Salmonella. Data were collected from 359 finishing-pig herds in Germany, Denmark, Greece, The Netherlands and Sweden, between 1996 and 1998. Pigs fed non-pelleted feed (dry or wet) had 2- and 2.5-times lower odds...

  17. Population decline in the Delta caribou herd with reference to other Alaskan herds

    Directory of Open Access Journals (Sweden)

    Patrick Valkenburg et al.

    1996-01-01

    Full Text Available After growing continuously for nearly 15 years, the Delta caribou herd began to decline in 1989. Most other Interior Alaskan herds also began declining. In the Delta herd, and in other herds, the declines were caused primarily by high summer mortality of calves and increased natural mortality of adult females. Other minor causes included increased winter mortality of calves, and reduced parturition rates of 3-year-old and older females. The decline in the Delta herd also coincided with increased wolf (Canis lupus numbers, winters with deeper than normal snow, and warm summers. Mean body weight of annual samples of 10-month-old female calves was consistently low during the decline. Except in some of the smallest Interior Alaskan herds, we conclude that evidence for population regulation in Alaskan caribou is weak, and that herds are likely to fluctuate within a wide range of densities due to complex interactions of predation and weather. Unless wolf numbers are influenced by man, the size of a caribou herd in a given year is likely to be largely a function of its size during the previous population low and the number of years of favorable weather in the interim.

  18. Benchmarking dairy herd health status using routinely recorded herd summary data.

    Science.gov (United States)

    Parker Gaddis, K L; Cole, J B; Clay, J S; Maltecca, C

    2016-02-01

    Genetic improvement of dairy cattle health through the use of producer-recorded data has been determined to be feasible. Low estimated heritabilities indicate that genetic progress will be slow. Variation observed in lowly heritable traits can largely be attributed to nongenetic factors, such as the environment. More rapid improvement of dairy cattle health may be attainable if herd health programs incorporate environmental and managerial aspects. More than 1,100 herd characteristics are regularly recorded on farm test-days. We combined these data with producer-recorded health event data, and parametric and nonparametric models were used to benchmark herd and cow health status. Health events were grouped into 3 categories for analyses: mastitis, reproductive, and metabolic. Both herd incidence and individual incidence were used as dependent variables. Models implemented included stepwise logistic regression, support vector machines, and random forests. At both the herd and individual levels, random forest models attained the highest accuracy for predicting health status in all health event categories when evaluated with 10-fold cross-validation. Accuracy (SD) ranged from 0.61 (0.04) to 0.63 (0.04) when using random forest models at the herd level. Accuracy of prediction (SD) at the individual cow level ranged from 0.87 (0.06) to 0.93 (0.001) with random forest models. Highly significant variables and key words from logistic regression and random forest models were also investigated. All models identified several of the same key factors for each health event category, including movement out of the herd, size of the herd, and weather-related variables. We concluded that benchmarking health status using routinely collected herd data is feasible. Nonparametric models were better suited to handle this complex data with numerous variables. These data mining techniques were able to perform prediction of health status and could add evidence to personal experience in herd

  19. Cultural Vignette: Mexican Americans.

    Science.gov (United States)

    Boyer, Mary Ellen; And Others

    Developed as part of a multicultural research project in the San Diego Community College District, this booklet presents the findings of a 10-member research team about various elements of Mexican-American culture. The areas covered are: (1) historical background on the Mexican heritage of the United States from pre-colonial times to the present…

  20. Gastrointestinal nematodes and anthelmintic resistance in Danish goat herds

    DEFF Research Database (Denmark)

    Holm, Signe A.; Sørensen, Camilla; Thamsborg, Stig M.

    2014-01-01

    The prevalence of gastrointestinal parasites in Danish goats and the presence of anthelmintic resistance (AR) in 10 selected herds were investigated during April-September 2012. All Danish herds (n = 137) with 10 or more adult goats were invited to participate, and of these 27 herds met the inclu......The prevalence of gastrointestinal parasites in Danish goats and the presence of anthelmintic resistance (AR) in 10 selected herds were investigated during April-September 2012. All Danish herds (n = 137) with 10 or more adult goats were invited to participate, and of these 27 herds met...

  1. Características de Carcaça e da Carne de Novilhos Filhos de Vacas 1/2 Nelore 1/2 Charolês e 1/2 Charolês 1/2 Nelore Acasaladas com Touros Charolês ou Nelore Carcass and Meat Characteristics of Steers Produced by 1/2 Nellore 1/2 Charolais and 1/2 Charolais 1/2 Nellore Cows Mated with Charolais and Nellore Bulls

    Directory of Open Access Journals (Sweden)

    Fabiano Nunes Vaz

    2002-07-01

    Full Text Available Este experimento foi conduzido com o objetivo de avaliar o efeito do cruzamento entre vacas 1/2 Nelore 1/2 Charolês com touros Charolês e 1/2 Charolês 1/2 Nelore com touros Nelore, sobre as características de carcaça e da carne de novilhos oriundos desses acasalamentos, abatidos aos dois anos de idade. Foram utilizados 80 novilhos 3/4 Nelore (N 1/4 Charolês (C e 136 novilhos 3/4 C 1/4 N. Os dados foram coletados de setembro de 1986 a dezembro de 1998. O modelo estatístico utilizado incluiu os efeitos classificatórios de grupo contemporâneo, idade da vaca e composição racial, bem como o efeito da idade do animal ao abate como covariável. Os novilhos 3/4 C 1/4 N foram superiores em peso de fazenda (468 contra 448 kg, conformação de carcaça (11,3 contra 10,4 pontos, porcentagem de músculo (66,9 contra 64,8%, área de Longissimus dorsi (69,5 contra 64,7 cm², área de Longissimus dorsi ajustada para o peso de carcaça fria (27,9 contra 26,6 cm², comprimento de carcaça (126 contra 123 cm, perímetro de braço (36,5 contra 35,4 cm e maciez da carne (6,50 contra 5,20 pontos, enquanto os 3/4 N 1/4 C apresentaram maiores rendimento de carcaça (54,6 contra 53,7%, comprimento de perna (74,0 contra 72,0 cm e de braço (41,5 contra 39,7 cm, espessura de gordura subcutânea (3,29 contra 2,70 mm e porcentagem de gordura na carcaça (19,5 contra 17,8%. Não foi verificada diferença significativa para peso de carcaça fria, cor, textura, marmoreio, palatabilidade e suculência da carne.The objective of the experiment was to evaluate the carcass and meat characteristics of two year old steers, produced by the mating of 1/2 Nellore 1/2 Charolais cows with Charolais bulls and by mating 1/2 Charolais 1/2 Nellore cows with Nellore bulls. Eighty 3/4 Nellore 1/4 Charolais (NC and 136 3/4 Charolais 1/4 Nellore steers were used. The data were collected from September 1986 to December 1998. In the statistical model were included the contemporary group

  2. Bacteriological etiology and treatment of mastitis in Finnish dairy herds

    National Research Council Canada - National Science Library

    Johanna Vakkamaki; Suvi Taponen; Anna-Maija Heikkila; Satu Pyorala

    2017-01-01

    .... This study addressed pathogen-specific microbiological data and treatment and culling records, in combination with cow and herd characteristics, from the Finnish dairy herd recording system during 2010-2012...

  3. The profitability and production of a beef herd on transitional ...

    African Journals Online (AJOL)

    The profitability and production of a beef herd on transitional Cymbopogon- Themeda ... emphasizes the need to optimize, rather than maximize, the rate of reproduction. ... Keywords: Beef cattle, cow herd production, extensive farming, lick ...

  4. An analysis of herding behavior in security analysts’ networks

    Science.gov (United States)

    Zhao, Zheng; Zhang, YongJie; Feng, Xu; Zhang, Wei

    2014-11-01

    In this paper, we build undirected weighted networks to study herding behavior among analysts and to analyze the characteristics and the structure of these networks. We then construct a new indicator based on the average degree of nodes and the average weighted clustering coefficient to research the various types of herding behavior. Our findings suggest that every industry has, to a certain degree, herding behavior among analysts. While there is obvious uninformed herding behavior in real estate and certain other industries, industries such as mining and nonferrous metals have informed herding behavior caused by analysts’ similar reactions to public information. Furthermore, we relate the two types of herding behavior to stock price and find that uninformed herding behavior has a positive effect on market prices, whereas informed herding behavior has a negative effect.

  5. Management plan for the Chisana caribou herd 2010-2015

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Chisana caribou herd (CCH) is a small international herd occurring in Yukon and Alaska on the Klutlan Plateau and near the headwaters of the White River. During...

  6. Gastrointestinal nematodes and anthelmintic resistance in Danish goat herds

    DEFF Research Database (Denmark)

    Holm, Signe A.; Sørensen, Camilla; Thamsborg, Stig M.;

    2014-01-01

    the presence of AR was analysed by egg hatch assay and FEC reduction tests using ivermectin (0.3 mg/kg) or fenbendazole (10.0 mg/kg). AR against both fenbendazole and ivermectin was detected in seven herds; AR against fenbendazole in one herd, and AR against ivermectin in another herd. In conclusion...

  7. E-herding : patterns of online mass-behavior

    NARCIS (Netherlands)

    Langley, D.J.; Hoeve, M.; Ortt, J.R.; Pals, N.

    2012-01-01

    Herding is convergent social behavior driven by inter-personal interaction, without centralized coordination. Herding in the online setting, which we call e-herding, is important for marketing scholars and practitioners because of its potential impact on product adoption and brand image and because

  8. Maximum herd efficiency in meat production I. Optima for slaughter ...

    African Journals Online (AJOL)

    changes in product value are important, it is easy to join them to herd cost efficiency for ... should be evaluated in terms of total herd or life cycle effi- ciency, and not only for a ..... The decline of herd efficiency with increases in b in. Table 2 is in ...

  9. House Price Forecasts, Forecaster Herding, and the Recent Crisis

    DEFF Research Database (Denmark)

    Stadtmann, Georg; Pierdzioch; Ruelke

    2013-01-01

    We used the Wall Street Journal survey data for the period 2006–2012 to analyze whether forecasts of house prices and housing starts provide evidence of (anti-)herding of forecasters. Forecasts are consistent with herding (anti-herding) of forecasters if forecasts are biased towards (away from...

  10. Some herding, record keeping and treatment methods used in Alaskan reindeer herds

    Directory of Open Access Journals (Sweden)

    Robert A. Dieterich

    1986-06-01

    Full Text Available Approximately 20000 reindeer (Rangifer tarandus in Alaska are gathered once or twice yearly to facilitate identification, serologic sampling, treatment and antler removal. Various air and land craft are used to bring the animals into a corral system from which they can be herded into a padded, pneumatically operated, squeeze apparatus. Ear tags are applied or read if already in place and ears are notched. A portable, computerized rapid data retrieval system is used to record reproductive success, vaccination and treatment status and other miscellaneous information. Ivermectin is being administered in the early winter months to treat reindeer in many herds for warbles, nasal bots and internal parasites. A killed, homologous Brucella suis type 4 vaccine is being used in two large (3500 herds. Efforts are being made to incorporate other innovative methods to improve herding and corralling methods.

  11. Herd- and sow-related risk factors for lameness in organic and conventional sow herds

    DEFF Research Database (Denmark)

    Knage-Rasmussen, Kristian Møllegaard; Houe, Hans; Rousing, Tine

    2014-01-01

    included in the study were clinical parameters and factors related to the production system. Sows were examined visually by one of four trained observers. The organic sows were assigned scores for lameness, body condition, hoof length, bursitis, abscesses and leg wounds, while the conventional sows were...... assigned scores for lameness, body condition and bursitis. A multivariable analysis was carried out by logistic regression with the herd and observer as random effects. The average herd lameness prevalence in gestation and lactation sows in organic herds was 11% in summer/autumn and 4.6% in winter....../spring. ‘Wounds, bursitis and abscess’ on legs (OR=4.7, P3 (OR=1.79, P=0.008) were associated with increased risk of lameness in Danish organic sow herds. Season (winter/spring v. summer/autumn) lowered the risk of lameness (OR=0.37, P

  12. Vaccination and herd immunity to infectious diseases

    Science.gov (United States)

    Anderson, Roy M.; May, Robert M.

    1985-11-01

    An understanding of the relationship between the transmission dynamics of infectious agents and herd immunity provides a template for the design of effective control programmes based on mass immunization. Mathematical models of the spread and persistence of infection provide important insights into the problem of how best to protect the community against disease.

  13. Diagnostic herd sensitivity using environmental samples

    DEFF Research Database (Denmark)

    Vigre, Håkan; Josefsen, Mathilde Hartmann; Seyfarth, Anne Mette;

    Due to logistic and economic benefits, the animal industry has an increased interest in using environmental samples to classify herds free of infections. For a valid interpretation of results obtained from environmental samples, the performance of the diagnostic method using these samples must...

  14. Cubicle Refusal in Norwegian Dairy Herds

    Directory of Open Access Journals (Sweden)

    Myren HJ

    2001-03-01

    Full Text Available In order to survey the behaviour of choosing the alley area instead of a cubicle as a lying place (cubicle refusal, a questionnaire was sent to the 273 dairy farms in Norway known to keep cows in cubicle housing systems. Sixty-six percent of the farmers contacted were included in the study. The median herd size was 18 cows (range 7–118. More than 85% of the herds had sheds providing one or more cubicles per cow. The mean herd occurrence of cubicle refusal was 6%, but showed great variation (range 0–55%. Regression analysis showed a significant association between rearing heifers in slatted floor pens and an increased cubicle refusal occurrence (p = 0.02, R2 = 0.05, while herd size, use of litter, or cubicle-to-animal ratio were not found to be associated with cubicle refusal. The practice of rearing heifers in slatted floor pens accounted for about one half of the observed cubicle refusal (etiologic fraction = 0.51.

  15. Visual monitoring of reproduction in dairy herds

    DEFF Research Database (Denmark)

    Thysen, Iver; Enevoldsen, Carsten

    1994-01-01

    Two complementary approaches to produce visual information from reproduction records are described and exemplified. The Event Display shows all reproductive events, over a year, for all cows in a herd, by symbols placed in an array with columns representing calendar weeks and rows representing in...

  16. Herd behavior in a complex adaptive system

    Science.gov (United States)

    Zhao, Li; Yang, Guang; Wang, Wei; Chen, Yu; Huang, J. P.; Ohashi, Hirotada; Stanley, H. Eugene

    2011-01-01

    In order to survive, self-serving agents in various kinds of complex adaptive systems (CASs) must compete against others for sharing limited resources with biased or unbiased distribution by conducting strategic behaviors. This competition can globally result in the balance of resource allocation. As a result, most of the agents and species can survive well. However, it is a common belief that the formation of a herd in a CAS will cause excess volatility, which can ruin the balance of resource allocation in the CAS. Here this belief is challenged with the results obtained from a modeled resource-allocation system. Based on this system, we designed and conducted a series of computer-aided human experiments including herd behavior. We also performed agent-based simulations and theoretical analyses, in order to confirm the experimental observations and reveal the underlying mechanism. We report that, as long as the ratio of the two resources for allocation is biased enough, the formation of a typically sized herd can help the system to reach the balanced state. This resource ratio also serves as the critical point for a class of phase transition identified herein, which can be used to discover the role change of herd behavior, from a ruinous one to a helpful one. This work is also of value to some fields, ranging from management and social science, to ecology and evolution, and to physics. PMID:21876133

  17. Herd factors associated with the serological Yersinia prevalence in fattening pig herds.

    Science.gov (United States)

    von Altrock, Alexandra; Roesler, Uwe; Waldmann, Karl-Heinz

    2011-12-01

    Recent epidemiological evidence has demonstrated that pork is an important source of yersiniosis in humans. Identifying risk factors and potential interventions in swine production that may decrease the risk of pork production contamination during harvest and processing is an important step before controlling Yersinia spp. Therefore, management strategies and production processes that might be associated with fattening pigs testing seropositive for pathogenic Yersinia spp. were investigated in 80 fattening pig farms. Although >70 farm characteristics were included in the risk assessment, there were only a few that seemed to be connected with serological prevalence: housing on a fully slatted floor and the use of municipal water were observed more often in herds with low serological Yersinia prevalence, whereas recurring health problems and a low daily weight gain compared with the mean of the herds included in the study were found in herds with a high prevalence. Besides, the Yersinia prevalence seemed to be inversely proportional to the herds' serological Salmonella status collected in accordance with German legislation. Additionally, the development of the serological Yersinia status of selected herds was assessed over a period of a year to gain knowledge of the dynamics of Yersinia infections in fattening pig herds. Three out of four serological negative herds maintained a low level of Yersinia prevalence, whereas one herd shifted between negative status and a prevalence of 100%. The reason for these considerable fluctuations could not be explained, and there was no direct association with the analyzed risk factors. Further research should be carried out to prove the given risk factors, especially the possible relation to the Salmonella prevalence before implementing a combined zoonoses surveillance and control program.

  18. House Price Forecasts, Forecaster Herding, and the Recent Crisis

    Directory of Open Access Journals (Sweden)

    Christian Pierdzioch

    2012-11-01

    Full Text Available We used the Wall Street Journal survey data for the period 2006–2012 to analyze whether forecasts of house prices and housing starts provide evidence of (anti-herding of forecasters. Forecasts are consistent with herding (anti-herding of forecasters if forecasts are biased towards (away from the consensus forecast. We found that anti-herding is prevalent among forecasters of house prices. We also report that, following the recent crisis, the prevalence of forecaster anti-herding seems to have changed over time.

  19. Herd-level risk factors for infection with bovine leukemia virus in Canadian dairy herds.

    Science.gov (United States)

    Nekouei, Omid; VanLeeuwen, John; Sanchez, Javier; Kelton, David; Tiwari, Ashwani; Keefe, Greg

    2015-05-01

    Enzootic bovine leukosis (EBL) is an economically important infection of dairy cattle worldwide, which is caused by bovine leukemia virus (BLV). The prevalence of infection in Canadian dairy herds is high and continues to increase; however, there has not been a national program to control BLV. This cross-sectional study was conducted to identify potentially important risk factors for BLV infection on Canadian dairy herds, which is a prerequisite to developing an effective control program. During 1998-2003, based on a stratified two-stage random sampling process, 315 dairy farms from seven provinces of Canada were selected. Within each farm, 9-45 cows were bled and tested with a commercial serum ELISA kit for BLV antibodies. A comprehensive questionnaire, targeting potentially important herd-level management indicators, was successfully administered in 272 herds. A zero-inflated negative binomial (ZINB) regression model was fit to the resulting data to assess the potential associations between BLV seropositivity and a variety of herd-level factors. Seventy-eight percent of the herds were identified as BLV-positive (had one or more test positive animals). In the negative-binomial part of the final ZINB model, herds with clinical cases of leukosis during the 12 months prior to sampling, as well as herds which purchased animals with unknown BLV infection status in the last five years, had a significantly larger proportion of BLV positive animals. Based on a significant interaction between two of the risk factors, changing gloves between cows during pregnancy examination was not statistically associated with lower proportion of infected cows compared with not changing gloves, in the western Canadian provinces. In the logistic part of the model, herds from eastern Canadian provinces and those not purchasing cows in the last five years had increased odds of being free from BLV. The high prevalence of infection across Canada should be addressed through the development and

  20. Comportamiento reproductivo de razas bovinas de carne europeas en condiciones de trópico húmedo mexicano (Reproductive behavior of european bovine races of meat under conditions of tropic humid mexican

    Directory of Open Access Journals (Sweden)

    Córdova-Izquierdo Alejandro

    2005-11-01

    Full Text Available El objetivo de este trabajo fue valorar el comportamiento reproductivo de razas bovinas europeas introducidas a condiciones de trópico húmedo mexicano. Se emplearon 36 novillonas prepúberes de raza Charolais, 2 sementales de la misma raza y 2 sementales de raza Limousin. Las vaquillas y los 2 sementales de la raza Charolais oscilando entre 250-310 kg. de peso corporal, con una edad promedio entre los 13 meses; los 2 sementales de raza Limousin con peso entre 480-500 Kg. y una edad de 20 meses promedio. El estudio se realizó en el Estado de Campeche, México, donde se valoró el comportamiento reproductivo de las novillonas, hasta alcanzar la madures sexual y empadre por mota directa. Posteriormente se evaluó diagnóstico de gestación por palpación rectal y se obtuvo el porcentaje de fertilidad, de 30.5%, aunque este porcentaje es bajo, estos resultados indican la posibilidad de introducir vaquillas Bos taurus al trópico húmedo sin problemas reproductivos, como días a primer calor, tiempo de empadre por mota directa y de comportamiento en ciclos estrales; no obstante, debe ser tomado en cuenta las condiciones físicas y biológicas de los animales y del medio en el cual se encuentren. The objective of this work was to value the reproductive behavior of races bovine Europeans introduced to conditions of tropic humid Mexican. 36 heifers of Charolais race, 2 sires of the same race and 2 sires of race Limousin was used. The heifers and the 2 sires of the race Charolais oscillating among 250-310 kg. of corporal weight, with an age average among the 13 months; the 2 sires of race Limousin with weight among 480-500 Kg. and an age of 20 months average. The study was carried out in the State of Campeche, Mexico, where the reproductive behavior of the heifers was valued, until reaching the you mature sexual and pair for direct mount. Later on it was evaluated diagnostic of gestation for rectal palpation and the percentage of fertility was

  1. A model for the contagion and herding

    Science.gov (United States)

    Caetano, Marco Antonio Leonel; Yoneyama, Takashi

    2011-11-01

    This work concerns the modeling of contagion and herding effects which can cause significant movements of prices and volatilities. The idea is to adapt some concepts borrowed from the Biological Sciences and that have emerged as useful analogies to model a variety of phenomena in a large variety of fields such as Engineering and Economics. In this work, the allegory of interacting particles is used to describe the contagion and emergence of herding behavior of financial agents leading to the formation of clusters. The main idea is to adapt the schemes originally employed in particle swarm optimization algorithms, together with the concepts of leaders and followers. As an illustration of the applicability of the proposed model, a case study is presented using data from the World Bank.

  2. Controlling herding in minority game systems

    CERN Document Server

    Zhang, Ji-Qiang; Wu, Zhi-Xi; Su, Riqi; Lai, Ying-Cheng

    2015-01-01

    Resource allocation takes place in various types of real-world complex systems such as urban traf- fic, social services institutions, economical and ecosystems. Mathematically, the dynamical process of complex resource allocation can be modeled as minority games in which the number of resources is limited and agents tend to choose the less used resource based on available information. Spontaneous evolution of the resource allocation dynamics, however, often leads to a harmful herding behavior accompanied by strong fluctuations in which a large majority of agents crowd temporarily for a few resources, leaving many others unused. Developing effective control strategies to suppress and elim- inate herding is an important but open problem. Here we develop a pinning control method. That the fluctuations of the system consist of intrinsic and systematic components allows us to design a control scheme with separated control variables. A striking finding is the universal existence of an optimal pinning fraction to mi...

  3. The Wealth of Mexican Americans

    Science.gov (United States)

    Cobb-Clark, Deborah A.; Hildebrand, Vincent A.

    2006-01-01

    This paper analyzes the sources of disparities in the relative wealth position of Mexican Americans. Results reveal that--unlike the racial wealth gap--Mexican Americans' wealth disadvantage is in large part not the result of differences in wealth distributions conditional on the underlying determinants of wealth. Rather, Mexican Americans' wealth…

  4. Demythologizing the Mexican American Father

    Science.gov (United States)

    Saracho, Olivia N.; Spodek, Bernard

    2008-01-01

    This review presents recent studies on Mexican American fathers in the United Sates to provide researchers with an understanding of contemporary fatherhood of Mexican American individuals. It describes the myths that create methodological and conceptual problems in conducting research studies to characterize Mexican American fathers. It also…

  5. [Herd immunity and effectiveness of vaccination].

    Science.gov (United States)

    Zielinski, Andrzej; Stefanoff, Pawel

    2004-01-01

    The effectiveness of vaccinations is discussed in relation to vaccine efficacy and effectiveness of vaccination programs. The types of epidemiological studies used in the assessment of vaccine effectiveness are presented, and most common sources of bias in such studies are listed. Basic formulas for calculation of vaccine effectiveness are given as applied for cohort and case-control studies. The definitions and ways of estimation of indicators of herd immunity as applied to the analysis of the effectiveness of vaccinations are presented.

  6. Monte Carlo Simulation of HERD Calorimeter

    CERN Document Server

    Xu, M; Dong, Y W; Lu, J G; Quan, Z; Wang, L; Wang, Z G; Wu, B B; Zhang, S N

    2014-01-01

    The High Energy cosmic-Radiation Detection (HERD) facility onboard China's Space Station is planned for operation starting around 2020 for about 10 years. It is designed as a next generation space facility focused on indirect dark matter search, precise cosmic ray spectrum and composition measurements up to the knee energy, and high energy gamma-ray monitoring and survey. The calorimeter plays an essential role in the main scientific objectives of HERD. A 3-D cubic calorimeter filled with high granularity crystals as active material is a very promising choice for the calorimeter. HERD is mainly composed of a 3-D calorimeter (CALO) surrounded by silicon trackers (TK) from all five sides except the bottom. CALO is made of 9261 cubes of LYSO crystals, corresponding to about 55 radiation lengths and 3 nuclear interaction lengths, respectively. Here the simulation results of the performance of CALO with GEANT4 and FLUKA are presented: 1) the total absorption CALO and its absorption depth for precise energy measure...

  7. Population dynamics of caribou herds in southwestern Alaska

    Directory of Open Access Journals (Sweden)

    Patrick Valkenburg

    2003-04-01

    Full Text Available The five naturally occurring and one transplanted caribou (Rangifer tarandus granti herd in southwestern Alaska composed about 20% of Alaska's caribou population in 2001. All five of the naturally occurring herds fluctuated considerably in size between the late 1800s and 2001 and for some herds the data provide an indication of long-term periodic (40-50 year fluctuations. At the present time, the Unimak (UCH and Southern Alaska Peninsula (SAP are recovering from population declines, the Northern Alaska Peninsula Herd (NAP appears to be nearing the end of a protracted decline, and the Mulchatna Herd (MCH appears to now be declining after 20 years of rapid growth. The remaining naturally occurring herd (Kilbuck has virtually disappeared. Nutrition had a significant effect on the size of 4-month-old and 10-month-old calves in the NAP and the Nushagak Peninsula Herd (NPCH and probably also on population growth in at least 4 (SAP, NAP, NPCH, and MCH of the six caribou herds in southwestern Alaska. Predation does not appear to be sufficient to keep caribou herds in southwestern Alaska from expanding, probably because rabies is endemic in red foxes (Vulpes vulpes and is periodically transferred to wolves (Canis lupus and other canids. However, we found evidence that pneumonia and hoof rot may result in significant mortality of caribou in southwestern Alaska, whereas there is no evidence that disease is important in the dynamics of Interior herds. Cooperative conservation programs, such as the Kilbuck Caribou Management Plan, can be successful in restraining traditional harvest and promoting growth in caribou herds. In southwestern Alaska we also found evidence that small caribou herds can be swamped and assimilated by large herds, and fidelity to traditional calving areas can be lost.

  8. Short communication: Bulk milk somatic cell penalties in herds enrolled in Dairy Herd Improvement programs.

    Science.gov (United States)

    Hand, K J; Godkin, M A; Kelton, D F

    2012-01-01

    The objective of this study was to determine the effect of somatic cell count (SCC) monitoring at the cow level through Dairy Herd Improvement (DHI) programs on the risk of bulk tank SCC (BTSCC) penalties. For the year 2009, BTSCC for all producers in Ontario were examined, for a total of 2,898 DHI herds, 1,186 non-DHI herds, and 48,250 BTSCC records. Two penalty levels were examined, where BTSCC exceeded 499,000 (P500) and 399,000 (P400) cells/mL. Data were modeled first to determine the odds of a BTSCC exceeding a set penalty threshold and second to determine the odds of incurring a penalty under the Ontario Milk Act. All data were modeled as a generalized mixed model with a binary link function. Random effects included herd, fixed effects included season of BTSCC (summer, May to September, and winter, October to April), total milk shipped per month (L), fat paid per month (kg), protein paid per month (kg), and participation or not in the DHI program. The likelihood of a BTSCC exceeding a penalty threshold in a non-DHI herd compared with a DHI herd was significantly greater than 1 at both penalty levels, where the odds ratios were estimated to be 1.42 [95% confidence interval (CI): 1.19 to 1.69] and 1.38 (95% CI: 1.25 to 1.54) for P500 and P400, respectively. The likelihood of incurring a BTSCC penalty (where 3 out of 4 consecutive BTSCC exceeded penalty thresholds) was not significantly different at P500; however, it was significantly different for P400, where the odds ratio was estimated to be 1.42 (95% CI: 1.12 to 1.81).

  9. k-Casein, b-lactoglobulin and growth hormone allele frequencies and genetic distances in Nelore, Gyr, Guzerá, Caracu, Charolais, Canchim and Santa Gertrudis cattle

    Directory of Open Access Journals (Sweden)

    Paola Augusta Kemenes

    1999-12-01

    Full Text Available The genotypes for k-casein (k-CN, b-lactoglobulin (b-LG and growth hormone (GH were determined by polymerase chain reaction (PCR and restriction enzyme digestion in seven breeds of cattle (Nelore, Gyr, Guzerá, Caracu, Charolais, Canchim and Santa Gertrudis. k-Casein had two alleles with the A allele occurring at a higher frequency in Bos indicus breeds (0.93, 0.92 and 0.91% for Gyr, Guzerá and Nelore, respectively. The b-lactoglobulin locus had two alleles in all of the breeds. European breeds had a higher frequency of the b-LG A allele than Zebu breeds. The GH locus had two alleles (L and V in Bos taurus and was monomorphic (L allele only in all of the Bos indicus breeds evaluated. The highest frequency for the V allele was observed in Charolais cattle. The markers used revealed a considerable similarity among breeds, with two main groups being discernible. One group consisted of Zebu and Santa Gertrudis breeds and the other consisted of European and Canchim breeds.Os genótipos de k-caseína (k-CN, b-lactoglobulina (b-LG e hormônio de crescimento foram determinados por reação em cadeia de polimerase (PCR e digestão com enzima de restrição em sete raças de bovinos (Nelore, Gir, Guzerá, Caracu, Charolesa, Canchim and Santa Gertrudis. A k-caseína apresentou dois alelos e as freqüências mais elevadas para o alelo A foram observadas em Bos indicus (0,93, 0,92 e 0,91% para as raças Gir, Guzerá e Nelore, respectivamente. A b-lactoglobulina apresentou dois alelos em todas as raças estudadas, sendo a freqüência do alelo A mais elevada nas raças européias. O loco de hormônio de crescimento apresentou dois alelos em Bos taurus e foi monomórfico (alelo L em todas as raças zebuínas. A maior freqüência para o alelo V foi observado na raça Charolesa. Os marcadores investigados revelaram alta similaridade entre as raças, com a formação de dois grupos principais: um composto de raças zebuínas e a raça Santa Gertrudis e outro

  10. Herding behaviour and sentiment: Evidence in a small European market

    Directory of Open Access Journals (Sweden)

    Elisabete F. Simões Vieira

    2015-01-01

    Full Text Available This work studies herding behaviour in a small European market, by analysing the stocks that constituted the Portuguese stock PSI-20 index, for the period between 2003 and 2011. The two different approaches used to measure herding intensity led to different results, suggesting that measurements of the herding phenomenon are sensitive to the method used. Consequently, there is a need for further research into the methodology used to test this phenomenon. Additionally, the study analyses the relationship between herd behaviour and investor sentiment, an area that has been little explored. In applying causality tests to the impact of sentiment on herd behaviour, only weak evidence is found that sentiment influences herding.

  11. Multifractality and herding behavior in the Japanese stock market

    Energy Technology Data Exchange (ETDEWEB)

    Cajueiro, Daniel O. [Universidade Catolica de Brasilia, Doutorado em Economia de Empresas, SGAN 916, Modulo B, Asa Norte, DF 70790-160 (Brazil); Tabak, Benjamin M. [Banco Central do Brasil, SBS Quadra 3, Bloco B, 9 andar, DF 70074-900 (Brazil)], E-mail: benjamin@ucb.br

    2009-04-15

    In this paper we present evidence of multifractality and herding behavior for a large set of Japanese stocks traded in the Tokyo Stock Exchange. We find evidence that herding behavior occurs in periods of extreme market movements. Therefore, based on the intuition behind the tests to detect herding phenomenon developed, for instance, in Christie and Huang [Christie W, Huang R. Following the pied pier: do individual returns herd around the market? Financ Analysts J 1995;51:31-7] and Chang et al. [Chang EC, Cheng JW, Khorana A. Examination of herd behavior in equity markets: an international perspective. J Bank Finance 2000;24:1651-99], we suggest that herding behavior may be one of the causes of multifractality.

  12. Technical indicators of financial performance in the dairy herd

    DEFF Research Database (Denmark)

    Kristensen, Erling Lundager; Østergaard, Søren; Krogh, Mogens Agerbo;

    2008-01-01

    Monte Carlo simulation was used to predict the long-term financial performance related to the technical performance of dairy herds. The indicators addressed were derived from data collected routinely in the herd. They indicated technical performance that can be affected by the farmer or the consu......Monte Carlo simulation was used to predict the long-term financial performance related to the technical performance of dairy herds. The indicators addressed were derived from data collected routinely in the herd. They indicated technical performance that can be affected by the farmer......" that used data extracted from ordinary management software to predict herd-specific financial performance related to major management changes. The metamodel was derived from systematic experiments with a complex simulation model that was used directly for advanced herd-specific decision support. We...

  13. Copper toxicity in a New Zealand dairy herd.

    Science.gov (United States)

    Johnston, Howard; Beasley, Laura; MacPherson, Neil

    2014-01-01

    Chronic copper toxicity was diagnosed in a Jersey herd in the Waikato region of New Zealand following an investigation into the deaths of six cattle from a herd of 250 dry cows. Clinical signs and post-mortem examination results were consistent with a hepatopathy, and high concentrations of copper in liver and blood samples of clinically affected animals confirmed copper toxicity. Liver copper concentrations and serum gamma-glutamyl transferase activities were both raised in a group of healthy animals sampled at random from the affected herd, indicating an ongoing risk to the remaining cattle; these animals all had serum copper concentrations within normal limits. Serum samples and liver biopsies were also collected and assayed for copper from animals within two other dairy herds on the same farm; combined results from all three herds showed poor correlation between serum and liver copper concentrations. To reduce liver copper concentrations the affected herd was drenched with 0.5 g ammonium molybdate and 1 g sodium sulphate per cow for five days, and the herd was given no supplementary feed or mineral supplements. Liver biopsies were repeated 44 days after the initial biopsies (approximately 1 month after the end of the drenching program); these showed a significant 37.3% decrease in liver copper concentrations (P record keeping, but multiple sources of copper contributed to a long term copper over supplementation of the herd; the biggest source of copper was a mineral supplement. The farmer perceived this herd to have problems with copper deficiency prior to the diagnosis of copper toxicity, so this case demonstrates the importance of monitoring herd copper status regularly. Also the poor correlation between liver and serum copper concentrations in the three herds sampled demonstrates the importance of using liver copper concentration to assess herd copper status.

  14. Gastrointestinal nematodes and anthelmintic resistance in Danish goat herds.

    Science.gov (United States)

    Holm, Signe A; Sörensen, Camilla R L; Thamsborg, Stig M; Enemark, Heidi L

    2014-01-01

    The prevalence of gastrointestinal parasites in Danish goats and the presence of anthelmintic resistance (AR) in 10 selected herds were investigated during April-September 2012. All Danish herds (n = 137) with 10 or more adult goats were invited to participate, and of these 27 herds met the inclusion criterion of more than 10 young kids never treated with anthelmintics. Questionnaire data on management were collected, and faecal samples from 252 kids were analysed by the McMaster technique. From all herds with a mean faecal egg count (FEC) above 300 eggs per g of faeces, pooled samples were stained with peanut agglutinin (PNA) for specific detection of Haemonchus contortus. Strongyle eggs were detected with an individual prevalence of 69%, including Nematodirus battus (3.6%) and other Nematodirus species (15.0%). Eimeria spp. were observed in 99.6% of the kids. H. contortus was found in 11 of 12 (92%) tested herds. Anthelmintics were used in 89% of the herds with mean treatment frequencies of 0.96 and 0.89 treatments per year for kids and adults, respectively. In 2011, new animals were introduced into 44% of the herds of which 25% practised quarantine anthelmintic treatments. In 10 herds the presence of AR was analysed by egg hatch assay and FEC reduction tests using ivermectin (0.3 mg/kg) or fenbendazole (10.0 mg/kg). AR against both fenbendazole and ivermectin was detected in seven herds; AR against fenbendazole in one herd, and AR against ivermectin in another herd. In conclusion, resistance to the most commonly used anthelmintics is widespread in larger goat herds throughout Denmark.

  15. What's Values Got to Do with It? Thriving among Mexican/Mexican American College Students

    Science.gov (United States)

    Morgan Consoli, Melissa L.; Llamas, Jasmín; Consoli, Andrés J.

    2016-01-01

    The authors examined traditional Mexican/Mexican American and perceived U.S. mainstream cultural values as predictors of thriving. One hundred twenty-four (37 men, 87 women) self-identified Mexican/Mexican American college students participated in the study. The traditional Mexican/Mexican American cultural values of family support and religion…

  16. Evaluation of the effect of alternative measurements of body weight gain and dry matter intake for the calculation of residual feed intake in growing purebred Charolais and Red Angus cattle.

    Science.gov (United States)

    Kayser, W; Glaze, J B; Welch, C M; Kerley, M; Hill, R A

    2015-07-01

    The objective of this study was to determine the effects of alternative-measurements of body weight and DMI used to evaluate residual feed intake (RFI). Weaning weight (WW), ADG, and DMI were recorded on 970 growing purebred Charolais bulls (n = 519) and heifers (n = 451) and 153 Red Angus growing steers (n = 69) and heifers (n = 84) using a GrowSafe (GrowSafe, Airdrie, Alberta, Canada) system. Averages of individual DMI were calculated in 10-d increments and compared to the overall DMI to identify the magnitude of the errors associated with measuring DMI. These incremental measurements were also used in calculation of RFI, computed from the linear regression of DMI on ADG and midtest body weight0.75 (MMWT). RFI_Regress was calculated using ADG_Regress (ADG calculated as the response of BW gain and DOF) and MMWT_PWG (metabolic midweight calculated throughout the postweaning gain test), considered the control in Red Angus. A similar calculation served as control for Charolais; RFI was calculated using 2-d consecutive start and finish weights (RFI_Calc). The RFI weaning weight (RFI_WW) was calculated using ADG_WW (ADG from weaning till the final out weight of the postweaning gain test) and MMWT_WW, calculated similarly. Overall average estimated DMI was highly correlated to the measurements derived over shorter periods, with 10 d being the least correlated and 60 d being the most correlated. The ADG_Calc (calculated using 2-d consecutive start and finish weight/DOF) and ADG_WW were highly correlated in Charolais. The ADG_Regress and ADG_Calc were highly correlated, and ADG_Regress and ADG_WW were moderately correlated in Red Angus. The control measures of RFI were highly correlated with the RFI_WW in Charolais and Red Angus. The outcomes of including abbreviated period DMI in the model with the weaning weight gain measurements showed that the model using 10 d of intake (RFI WW_10) was the least correlated with the control measures. The model with 60 d of intake had

  17. Mexican Folkart for Children.

    Science.gov (United States)

    Dominguez, Graciela; And Others

    Directions, suggested materials, and illustrations are given for making paper mache pinatas and masks, cascarones, Ojos de Dios, maracas, dresser scarf embroidery, burlap murals, yarn designs, paper plate trays, paper cut designs, the poppy, sarape aprons, and paper Mexican dolls. Filled with candy and broken, the pinata is used on most Mexican…

  18. A Financial Market Model Incorporating Herd Behaviour.

    Science.gov (United States)

    Wray, Christopher M; Bishop, Steven R

    2016-01-01

    Herd behaviour in financial markets is a recurring phenomenon that exacerbates asset price volatility, and is considered a possible contributor to market fragility. While numerous studies investigate herd behaviour in financial markets, it is often considered without reference to the pricing of financial instruments or other market dynamics. Here, a trader interaction model based upon informational cascades in the presence of information thresholds is used to construct a new model of asset price returns that allows for both quiescent and herd-like regimes. Agent interaction is modelled using a stochastic pulse-coupled network, parametrised by information thresholds and a network coupling probability. Agents may possess either one or two information thresholds that, in each case, determine the number of distinct states an agent may occupy before trading takes place. In the case where agents possess two thresholds (labelled as the finite state-space model, corresponding to agents' accumulating information over a bounded state-space), and where coupling strength is maximal, an asymptotic expression for the cascade-size probability is derived and shown to follow a power law when a critical value of network coupling probability is attained. For a range of model parameters, a mixture of negative binomial distributions is used to approximate the cascade-size distribution. This approximation is subsequently used to express the volatility of model price returns in terms of the model parameter which controls the network coupling probability. In the case where agents possess a single pulse-coupling threshold (labelled as the semi-infinite state-space model corresponding to agents' accumulating information over an unbounded state-space), numerical evidence is presented that demonstrates volatility clustering and long-memory patterns in the volatility of asset returns. Finally, output from the model is compared to both the distribution of historical stock returns and the market

  19. Clinical course of digital dermatitis lesions in an endemically infected herd without preventive herd strategies

    NARCIS (Netherlands)

    Holzhauer, M.; Bartels, C.J.M.; Dopfer, D.; Schaik, van G.

    2008-01-01

    Lactating Holstein-Friesian dairy cows in four separately housed groups in a herd with endemic digital dermatitis (E)D) were monitored weekly for 4 weeks in December 2004 for the presence of and transition between five stages (MO-M4) of DD. Cows were also monitored for the presence of heel horn eros

  20. Using routinely recorded herd data to predict and benchmark herd and cow health status

    Science.gov (United States)

    Genetic improvement of dairy cattle health using producer-recorded data is feasible. Estimates of heritability are low, indicating that genetic progress will be slow. Improvement of health traits may also be possible with the incorporation of environmental and managerial aspects into herd health pro...

  1. Using a Herd Profile to Determine Age-Specific Prevalence of Bovine Leukemia Virus in Michigan Dairy Herds

    Directory of Open Access Journals (Sweden)

    Ronald J. Erskine

    2012-01-01

    Full Text Available Enzootic bovine leukosis is a contagious disease of cattle caused by the retrovirus, bovine leukemia virus (BLV and is the most common cause of malignant neoplasm in cattle. In order to facilitate surveillance of this disease in dairy herds, we developed a method to combine ELISA of milk collected during routine production testing with a prescribed sampling of cows that is independent of the proportion of cows within each lactation. In 113 Michigan dairy herds, milk samples from ten cows in each of the 1st, 2nd, 3rd, and ≥4th lactations were analyzed for anti-Bovine Leukemia Virus (BLV antibodies by milk ELISA. For each herd, a BLV herd profile (BHP was calculated as the simple average of the percent of BLV-positive cows within each of the four lactation groups. The mean BHP for all herds was 32.8%, with means of 18.5, 28.8, 39.2, and 44.8% of 1st, 2nd, 3rd, and ≥4th lactation animals infected, respectively. In eight herds, we determined the correlation between the BHP, and true herd prevalence by testing the entire lactating herd (r=0.988,  P<0.0001. The BHP allows discrimination of lactation-specific BLV prevalence within a dairy herd, to help identify risk factors and management plans that may be important in transmission of BLV.

  2. 59 FR- Intent To Gather Wild Horses From the Owyhee Herd Management Area

    Science.gov (United States)

    1994-10-17

    ... Bureau of Land Management [ID-015-1060-04] Intent To Gather Wild Horses From the Owyhee Herd Management... Hardtrigger and Black Mountain Herd Areas located within the Owyhee Herd Management Area. A public...

  3. Bovine tuberculosis and its risk factors among dairy cattle herds in ...

    African Journals Online (AJOL)

    In a multivariable logistic regression analysis, being cross breed .... objective of this dairy system is to sale milk as a means of additional cash income. ... and herd characteristics (such as dairy herd management system, herd size, keeping of ...

  4. Development of a Simherd web application for herd health advisors - experiences and perspectives

    DEFF Research Database (Denmark)

    Østergaard, Søren; Ettema, Jehan Frans; Kudahl, Anne Braad

    2010-01-01

    SimHerd is a computer model of a dairy herd. In more than a decade the model has been applied and further developed within the research in herd management and animal health economics in dairy herds. Analyses with the SimHerd model have been included in 2 doctoral theses, 9 PhD theses, 4 MSc these....... The following describes experiences with developing a commercial herd health advisory tool based on the history of the research tool - SimHerd.......SimHerd is a computer model of a dairy herd. In more than a decade the model has been applied and further developed within the research in herd management and animal health economics in dairy herds. Analyses with the SimHerd model have been included in 2 doctoral theses, 9 PhD theses, 4 MSc theses...

  5. The prevalence of hypertension in older Mexicans and Mexican Americans.

    Science.gov (United States)

    Salinas, Jennifer J; Eschbach, Karl A; Markides, Kyriakos S

    2008-01-01

    To evaluate the prevalence of hypertension in older Mexicans in the United States and Mexico. Stratified by sex, logistic regression models to predict physician-diagnosed hypertension were conducted by using the Hispanic Established Populations for Epidemiologic Study of the Elderly (wave 3) and the Mexican Health and Aging Study (age > or =70 years) datasets. Older Mexican and Mexican American women have a greater prevalence of hypertension than their male counterparts. Mexican women who have migrated to the United States and returned to Mexico have similarly high rates of hypertension as their female counterparts in the United States. After adjusting for demographic characteristics, diabetes, obesity, alcohol use, and smoking, older Mexican women who have migrated to the United States are at increased risk for hypertension. Conversely, immigrant older Mexican American men are at significantly lower odds of hypertension. Sex differences exist in hypertension risk for older Mexicans and Mexican Americans living in the United States and Mexico. Older women who migrate to the United States are at a particular risk for hypertension in Mexico.

  6. Herd health and management of dairy cow

    Science.gov (United States)

    Ćaǧlayan, Alper; Yüca, Songül

    2016-04-01

    Herd management requires multidisciplinary practices including animal feeding, gynecology, artificial insemination, immunology, and similar topics. Animal feeding is the most delicate subject as the fodder expense is 70% of the farm cost and as nearly all of the metabolic diseases arising out as health problem are because of misfeeding. However, a business organization's being able to maintain making profit will be possible by taking a healthy calf from breeding herd every year. For this reason, precision registrations of birth and artificial insemination, following-up pregnant state of animals, and making the other animals pregnant as soon as possible should be primary aim. It should not be forgotten that diarrhea and pneumonia in calves are among the most frequently witnessed infection related health problems. Mastitis, metritis and foot diseases take an important place in mature cows. These diseases can be minimized by vaccinations that are done properly and in suitable time, in-service training of staffs, making shelters suitable for animals welfare, and improving the hygienic conditions.

  7. Controlling herding in minority game systems

    Science.gov (United States)

    Zhang, Ji-Qiang; Huang, Zi-Gang; Wu, Zhi-Xi; Su, Riqi; Lai, Ying-Cheng

    2016-02-01

    Resource allocation takes place in various types of real-world complex systems such as urban traffic, social services institutions, economical and ecosystems. Mathematically, the dynamical process of resource allocation can be modeled as minority games. Spontaneous evolution of the resource allocation dynamics, however, often leads to a harmful herding behavior accompanied by strong fluctuations in which a large majority of agents crowd temporarily for a few resources, leaving many others unused. Developing effective control methods to suppress and eliminate herding is an important but open problem. Here we develop a pinning control method, that the fluctuations of the system consist of intrinsic and systematic components allows us to design a control scheme with separated control variables. A striking finding is the universal existence of an optimal pinning fraction to minimize the variance of the system, regardless of the pinning patterns and the network topology. We carry out a generally applicable theory to explain the emergence of optimal pinning and to predict the dependence of the optimal pinning fraction on the network topology. Our work represents a general framework to deal with the broader problem of controlling collective dynamics in complex systems with potential applications in social, economical and political systems.

  8. Seroprevalence of border disease in Danish sheep and goat herds

    DEFF Research Database (Denmark)

    Tegtmeier, C.; Stryhn, H.; Uttenthal, Åse

    2000-01-01

    A study was conducted in 1994-96 with the aim of assessing the serological prevalence of Border Disease (BD) among sheep and goats in Denmark and to investigate possible relations to herd factors. From each of 1000 herds, 2 blood samples were obtained from animals older than 1 year. The examinati...

  9. The Consequences of Endogenizing Information for Herd Behavior

    NARCIS (Netherlands)

    O.H. Swank (Otto); B. Visser (Bauke)

    2003-01-01

    textabstractIn models of sequential decision making herd behaviour occurs if the signals smart (dumb) agents receive are (un)correlated and if agents have reputational concerns. We show that introducing costly effort to become informed about project payoffs (i) eliminates herd behaviour and (ii) shi

  10. Patterns of Herding and their Occurrence in an Online Setting

    NARCIS (Netherlands)

    Langley, David J.; Hoeve, Maarten C.; Ortt, J. Roland; Pals, Nico; van der Vecht, Bob

    2014-01-01

    When groups of consumers share information or express their opinions about products and services, their attitudes or behavior sometime align without centralized coordination, a phenomenon known as herding. Building on pattern-based explanations of herding from the cognitive science literature, we pr

  11. Seroprevalence of border disease in Danish sheep and goat herds

    DEFF Research Database (Denmark)

    Tegtmeier, C.; Stryhn, H.; Uttenthal, Åse;

    2000-01-01

    A study was conducted in 1994-96 with the aim of assessing the serological prevalence of Border Disease (BD) among sheep and goats in Denmark and to investigate possible relations to herd factors. From each of 1000 herds, 2 blood samples were obtained from animals older than 1 year. The examinati...

  12. Financial aspects of veterinary herd health management programmes

    NARCIS (Netherlands)

    Ifende, V.I.; Derks, M.; Hooijer, G.A.; Hogeveen, H.

    2014-01-01

    Veterinary herd health management (VHHM) programmes are meant to support herd health and farmers’ income (Brand and Guard 1996). They were introduced in the Netherlands in the 1970s (Sol and Renkema 1984) and at present many veterinarians provide them to farmers. VHHM comprises a basic structure of

  13. Patterns of Herding and their Occurrence in an Online Setting

    NARCIS (Netherlands)

    Langley, David J.; Hoeve, Maarten C.; Ortt, J. Roland; Pals, Nico; van der Vecht, Bob

    2014-01-01

    When groups of consumers share information or express their opinions about products and services, their attitudes or behavior sometime align without centralized coordination, a phenomenon known as herding. Building on pattern-based explanations of herding from the cognitive science literature, we pr

  14. Patterns of herding and their occurrence in an online setting

    NARCIS (Netherlands)

    Langley, D.J.; Hoeve, M.C.; Ortt, J.R.; Pals, N.; Vecht, B. van der

    2014-01-01

    When groups of consumers share information or express their opinions about products and services, their attitudes or behavior sometime align without centralized coordination, a phenomenon known as herding. Building on pattern-based explanations of herding from the cognitive science literature, we pr

  15. Patterns of herding and their occurrence in an online setting

    NARCIS (Netherlands)

    Langley, D.J.; Hoeve, M.C.; Ortt, J.R.; Pals, N.; Vecht, B. van der

    2014-01-01

    When groups of consumers share information or express their opinions about products and services, their attitudes or behavior sometime align without centralized coordination, a phenomenon known as herding. Building on pattern-based explanations of herding from the cognitive science literature, we pr

  16. Mexican Migration: Assessing Root Causes

    Science.gov (United States)

    2007-06-01

    66 Figure 4 is derived from John Scott, “Metas y Mecanismo ,” Centro de Investigacion y Docencia Economicas...John Scott, “Metas y Mecanismo ,” 4. 31 Another explanation for the increase in migration concerns neither the Mexican economy nor the Mexican...Dominant Regime,” 135. 82 John Scott, “Metas y Mecanismo ,” 5. 83 World Bank: Mexican Health Foundation, “Trends and Empirical Causes of Violent

  17. An Examination of Herd Behavior in The Indonesian Stock Market

    Directory of Open Access Journals (Sweden)

    Adi Vithara Purba

    2012-01-01

    Full Text Available We examine herd behavior in Indonesian Stock Exchange, using daily and weekly stocks returnfrom 2007 until 2010. We employ the cross sectional standard deviation of returns (CSSD methodologydeveloped by Christie and Huang (1995 and cross sectional absolute dispersion (CSAD methodologydeveloped by Chang et al. (2000 to detect the presence of herd behavior. Using daily andweekly CSSD, we document the nonexistence of herding behavior in Indonesian stock market. However,using CSAD of either data frequency the result demonstrates the presence of herding behavior,particularly on big capitalization and liquid stocks. The result differs from Chang et al. (2000 whofind no different impact of herding behavior across size-based portfolios.

  18. Diagnostic studies of abortion in Danish dairy herds

    DEFF Research Database (Denmark)

    Agerholm, J.S.; Willadsen, C. M.; Nielsen, Thomas Krogh

    1997-01-01

    Diagnostic findings in 218 aborted bovine foetuses are reported. The materials were examined in a matched case-control study of 69 Danish dairy herds with a sudden increase in the number of abortions and a corresponding 69 control herds. Foetuses aborted during the subsequent 6-month period were...... examined to identify the cause of abortion if possible. A total of 186 specimens were submitted from case herds and 32 from control herds. A likely cause of abortion was diagnosed in 73 foetuses. The most common cause was bovine viral diarrhoea virus (BVDV: 13%) followed by Neospora caninum infection (10......%), mycosis (5%) and Bacillus licheniformis infection (4%). Foetal and/or placental lesions were found in a further 27 cases. Only BVDV infection and neosporosis were diagnosed in more than one foetus per herd and only protozoal associated abortions occurred significantly more frequently in the case, rather...

  19. Mexican Virtual Solar Observatory

    Science.gov (United States)

    Santillan, A.; Hernandez-Cervantes, L.; Gonzalez-Ponce, A.; Hill, F.; Blanco-Cano, X.

    2007-12-01

    The Virtual Solar Observatory (VSO) concept contains software tools for searching, manipulating, and analyzing data from archives of solar data at many different observatories around the world (Hill 2000). The VSO not only provides fast and reliable access to the existing solar data, but also represents a powerful and unique machinery to perform numerical simulations for the evolution of a variety of different phenomena associated with solar activity. Two Mexican Universities, Universidad Nacional Autónoma de México and the Universidad de Sonora, are working together to create the Mexican Virtual Solar Observatory (MVSO) that will be part of a wider National effort. In this work we present a general description of the MVSO project, as well as the advances obtained in the development of Graphical User Interfaces (GUI) to Remotely Perform Numerical Simulation of the Evolution of Coronal Mass Ejection in the Interplanetary Medium.

  20. Spatial modelling of the between-herd infection dynamics of bovine virus diarrhoea virus (BVDV) in dairy herds in Denmark

    DEFF Research Database (Denmark)

    Ersbøll, Annette Kjær; Ersbøll, Bjarne Kjær; Houe, H.

    2010-01-01

    According to the current literature BVDV-infected neighbours probably impose a high risk of infection of susceptible cattle herds. In the present study, the objective was to evaluate the risk of a dairy herd changing infection status (from not having persistently infected (PI) animals to having PI-animals...

  1. Modelling the spread of bovine viral diarrhea virus (BVDV) in a beef cattle herd and its impact on herd productivity.

    Science.gov (United States)

    Damman, Alix; Viet, Anne-France; Arnoux, Sandie; Guerrier-Chatellet, Marie-Claude; Petit, Etienne; Ezanno, Pauline

    2015-02-24

    Bovine viral diarrhea virus (BVDV) is a common pathogen of cattle herds that causes economic losses due to reproductive disorders in breeding cattle and increased morbidity and mortality amongst infected calves. Our objective was to evaluate the impact of BVDV spread on the productivity of a beef cow-calf herd using a stochastic model in discrete time that accounted for (1) the difference in transmission rates when animals are housed indoors versus grazing on pasture, (2) the external risk of disease introductions through fenceline contact with neighboring herds and the purchase of infected cattle, and (3) the risk of individual pregnant cattle generating persistently infected (PI) calves based on their stage in gestation. The model predicted the highest losses from BVDV during the first 3 years after disease was introduced into a naive herd. During the endemic phase, the impact of BVDV on the yearly herd productivity was much lower due to herd immunity. However, cumulative losses over 10 years in an endemic situation greatly surpassed the losses that occurred during the acute phase. A sensitivity analysis of key model parameters revealed that herd size, the duration of breeding, grazing, and selling periods, renewal rate of breeding females, and the level of numerical productivity expected by the farmer had a significant influence on the predicted losses. This model provides a valuable framework for evaluating the impact of BVDV and the efficacy of different control strategies in beef cow-calf herds.

  2. [On Mexican medicinal plants].

    Science.gov (United States)

    de Micheli, Alfredo; Izaguirre-Avila, Raúl

    2009-12-01

    During the XVIII century, two Spanish scientific expeditions arrived here led, respectively, by the naturalist Martín Sessé and by the Italian mariner Alessandro Malaspina di Mulazzo, dependent from the Spanish Government. The members collected a rich scientific material, which was carried to Madrid in 1820. At the end of XVIII century, the Franciscan friar Juan Navarro depicted and described several Mexican medicinal plants in the fifth volume of his "American Garden". In the last years of the Colonial period, fundamental works of Humboldt and Bonpland, on the geographic distribution of the American plants, were published. At the end of the XIX century, the first researches on the Mexican medicinal botany were performed at the laboratory of the "Instituto Médico Nacional" under the leadership of doctor Fernando Altamirano, starting pharmacological studies in our country. During the first half of the XX century, trials of cardiovascular pharmacology were performed in the small laboratories of the cardiological unit at the General Hospital of Mexico, due to doctor Ignacio Chávez, initiative. Mexican botanical-pharmacological tradition remains alive and vigorous in the modern scientific institutes of the country.

  3. Optimizing breeding decisions for Finnish dairy herds.

    Science.gov (United States)

    Rajala-Schultz, P J; Gröhn, Y T; Allore, H G

    2000-01-01

    The purpose of this study was to determine the effect of reproductive performance on profitability and optimal breeding decisions for Finnish dairy herds. We used a dynamic programming model to optimize dairy cow insemination and replacement decisions. This optimization model maximizes the expected net revenues from a given cow and her replacements over a decision horizon. Input values and prices reflecting the situation in 1998 in Finland were used in the study. Reproductive performance was reflected in the model by overall pregnancy rate, which was a function of heat detection and conception rate. Seasonality was included in conception rate. The base run had a pregnancy rate of 0.49 (both heat detection and conception rate of 0.7). Different scenarios were modeled by changing levels of conception rate, heat detection, and seasonality in fertility. Reproductive performance had a considerable impact on profitability of a herd; good heat detection and conception rates provided an opportunity for management control. When heat detection rate decreased from 0.7 to 0.5, and everything else was held constant, net revenues decreased approximately 2.6%. If the conception rate also decreased to 0.5 (resulting in a pregnancy rate of 0.25), net revenues were approximately 5% lower than with a pregnancy rate of 0.49. With lower fertility, replacement percentage was higher and the financial losses were mainly from higher replacement costs. Under Finnish conditions, it is not optimal to start breeding cows calving in spring and early summer immediately after the voluntary waiting period. Instead, it is preferable to allow the calving interval to lengthen for these cows so that their next calving is in the fall. However, cows calving in the fall should be bred immediately after the voluntary waiting period. Across all scenarios, optimal solutions predicted most calvings should occur in fall and the most profitable time to bring a replacement heifer into a herd was in the fall. It

  4. Paratuberculosis sero-status and milk production, SCC and calving interval in Irish dairy herds

    Directory of Open Access Journals (Sweden)

    Hoogendam K

    2009-04-01

    Full Text Available Abstract The objective of this study was to investigate the impact of paratuberculosis sero-status on milk yield, fat, protein, somatic cell count and calving interval in Irish dairy herds. Serum from all animals over 12 months of age (n = 2,602 in 34 dairy herds was tested for antibodies to Mycobacterium avium subsp. paratuberculosis using an ELISA. Herds were categorised by sero-status into positive, non-negative and negative, where a positive herd contained two or more positive cows, a non-negative herd contained only one positive cow and a negative herd contained no positive cows. Data at animal, parity and herd-level were analysed by multiple regression using general linear models. Positive herds (mean herd size = 129 cows and non-negative herds (81 cows were larger than negative herds (72 cows (P

  5. Connectedness among herds of beef cattle bred under natural service

    Directory of Open Access Journals (Sweden)

    Piedrafita Jesús

    2010-02-01

    Full Text Available Abstract Background A procedure to measure connectedness among herds was applied to a beef cattle population bred by natural service. It consists of two steps: (a computing coefficients of determination (CDs of comparisons among herds; and (b building sets of connected herds. Methods The CDs of comparisons among herds were calculated using a sampling-based method that estimates empirical variances of true and predicted breeding values from a simulated n-sample. Once the CD matrix was estimated, a clustering method that can handle a large number of comparisons was applied to build compact clusters of connected herds of the Bruna dels Pirineus beef cattle. Since in this breed, natural service is predominant and there are almost no links with reference sires, to estimate CDs, an animal model was used taking into consideration all pedigree information and, especially, the connections with dams. A sensitivity analysis was performed to contrast single-trait sire and animal model evaluations with different heritabilities, multiple-trait animal model evaluations with different degrees of genetic correlations and models with maternal effects. Results Using a sire model, the percentage of connected herds was very low even for highly heritable traits whereas with an animal model, most of the herds of the breed were well connected and high CD values were obtained among them, especially for highly heritable traits (the mean of average CD per herd was 0.535 for a simulated heritability of 0.40. For the lowly heritable traits, the average CD increased from 0.310 in the single-trait evaluation to 0.319 and 0.354 in the multi-trait evaluation with moderate and high genetic correlations, respectively. In models with maternal effects, the average CD per herd for the direct effects was similar to that from single-trait evaluations. For the maternal effects, the average CD per herd increased if the maternal effects had a high genetic correlation with the direct

  6. Reproductive performance in a select sample of dairy herds.

    Science.gov (United States)

    Ferguson, James D; Skidmore, Andrew

    2013-02-01

    Sixteen herds were selected from a pool of 64 herds nominated by consultants for participation in a national survey to demonstrate excellence in reproductive performance. For inclusion in the survey, herds had to have comprehensive records in a farm computer database or participate in a Dairy Herd Improvement Association record system and have superior reproductive performance as judged by the herd advisor. Herd managers were asked to fill out a questionnaire to describe their reproductive management practices and provide herd records for data analysis. Reproductive analysis was based on individual cow records for active and cull dairy cows that calved during the calendar year 2010. Breeding records by cow were used to calculate indices for insemination rate (IR), conception rate (CR), pregnancy rate (PR), and culling. Herds ranged in size from 262 to 6,126 lactating and dry cows, with a mean of 1,654 [standard deviation (SD) 1,494] cows. Mean days to first insemination (DFS) was 71.2d (SD 4.7d), and IR for first insemination was 86.9%. Mean days between inseminations were 33.4d (SD 3.1d), and 15.4% of insemination intervals were greater than 48 d (range: 7.2 to 21.5%). First-service conception rate was 44.4% (SD 4.8%) across all herds and ranged from 37.5 to 51.8%. Mean PR was 32.0% (SD 3.9%) with a range of 26.5 to 39.4%. Lactation cull rate was 32.2% (SD 12.4%) with a range from 13.6 to 58.1%. Compared with mean data and SD for herds in the Raleigh Dairy Herd Improvement Association system, mean indices for these herds ranked them in the 99 th percentile for IR (using heat detection rate as comparison), 99 th percentile for PR, the bottom 18.6 percentile for DFS, and around the 50th percentile for CR. This suggests that excellent herd reproductive performance was associated with reproductive management that resulted in high insemination rates combined with average CR.

  7. Escherichia coli O157 prevalence in Dutch poultry, pig finishing and veal herds and risk factors in Dutch veal herds.

    Science.gov (United States)

    Schouten, J M; van de Giessen, A W; Frankena, K; De Jong, M C M; Graat, E A M

    2005-08-12

    In the period October 1996 through December 2000, a total of 7163 pooled faecal samples of laying hen and broiler flocks, finishing-pig herds and veal herds were examined for the presence of Salmonella spp., Campylobacter spp. and verocytotoxin-producing Escherichia coli O157 as part of a national monitoring programme in The Netherlands. Isolates were tested for eae and VT genes. Risk factors for Dutch veal herds were quantified. For all herd/flock types, faecal samples were cultured for E. coli O157. Of broiler flocks, laying flocks and finishing pig herds, respectively, 1.7%, 0.5% and 0.4% were E. coli O157 positive. In total, 42 of the 454 veal herds (9.3%) showed at least one positive pooled sample. E. coli O157-positive herds were compared (with logistic regression) to negative herds, regarding variables obtained from the questionnaire taken from the farm manager. To account for season, a sine function was included in the logistic regression as offset variable. In the final model, 'pink-veal production' (compared to white-veal production), 'group housing of the sampled herd' (compared to individual housing), 'more than one stable present' (compared to one stable present), 'hygienic measures regarding visitors' (compared to no hygienic measures), 'interval arrival-sampling of a herd of >20 weeks' (compared to < or =10 weeks), and 'presence of other farms within 1 km' (compared to no presence of farms <1 km) showed associations (P<0.05) with the presence of E. coli O157. These results need careful interpretation; they should be considered as indications for further (experimental or cohort-based) research rather then causal associations.

  8. Multiple anthelmintic resistance in a goat herd.

    Science.gov (United States)

    Zajac, A M; Gipson, T A

    2000-01-01

    Anthelmintic resistance was monitored over a 30 month period within a goat herd in eastern Virginia, USA. Resistance to ivermectin, levamisole and benzimidazole drugs was detected in Haemonchus contortus using the fecal egg count reduction test (FECRT). When levamisole use was discontinued for 1 year, susceptibility to levamisole appeared to return. Although a single treatment with fenbendazole was able to reduce fecal egg counts by only 50%, two doses administered in a 12 h interval increased efficacy to 92%, however, confidence intervals indicated that resistance was still present. When fecal egg counts were determined the following year after several treatment using this protocol, the efficacy of fenbendazole had fallen again to 57% reduction in fecal egg counts. The predominant genus present in cultured composite fecal samples was Haemonchus. Trichostrongylus, Cooperia and Teladorsagia were also present in smaller numbers.

  9. Specific pathogen-free pig herds also free from Campylobacter?

    Science.gov (United States)

    Kolstoe, E M; Iversen, T; Østensvik, Ø; Abdelghani, A; Secic, I; Nesbakken, T

    2015-03-01

    As Specific Pathogen-Free (SPF) pig herds are designed and managed to prevent specific pig diseases, it might be feasible to expand the list of micro-organisms also including zoonotic pathogens such as Campylobacter coli as this agent has its origin in pigs. In a previous survey, 15 of 16 of SPF herds were found free from human pathogenic Yersinia enterocolitica. Accordingly, three nucleus and seven multiplying herds were surveyed for Campylobacter to investigate whether the Norwegian SPF pig pyramid also might be free from this agent. In conclusion, the intervention of Campylobacter at the herd level might be possible as four of 10 SPF herds tested negative in two sets of samples from both autumn 2008 and summer/early autumn 2010. The four negative herds were all located in remote areas several kilometres away from conventional pig farming while the positive SPF farms were all situated in neighbourhoods with conventional pig production. It seems more difficult to control Campylobacter than some specific animal disease agents and another significant zoonotic agent, Y. enterocolitica, in pig herds. © 2014 Blackwell Verlag GmbH.

  10. Defining the Pen Islands Caribou Herd of southern Hudson Bay

    Directory of Open Access Journals (Sweden)

    Kenneth F. Abraham

    1998-03-01

    Full Text Available In this paper, we describe the Pen Islands Herd of caribou, the largest aggregation of caribou in Ontario (it also occupies a portion of northeastern Manitoba. Photographic counts showed the herd had a minimum population of 2300 in 1979, 4660 in 1986, 7424 in 1987 and 10 798 in 1994. Throughout the 1980s, the Pen Islands caribou exhibited population behaviour similar to migratory barren-ground caribou herds, although morphology suggests they are woodland caribou or possibly a mixture of subspecies. The herd had well-defined traditional tundra calving grounds, formed nursery groups and large mobile post-calving aggregations, and migrated over 400 km between tundra summer habitats and boreal forest winter habitats. Its migration took it into three Canadian jurisdictions (Ontario, Manitoba, Northwest Territories and it was important to residents of both Manitoba and Ontario. It is clear that the herd should be managed as a migratory herd and the critical importance of both the coastal and variable large winter ranges should be noted in ensuring the herd's habitat needs are secure.

  11. On Being a Mexican American.

    Science.gov (United States)

    Mendoza, Joe I.

    1994-01-01

    A well-acculturated migrant education program director reminisces about his Mexican upbringing in the United States, noting the persistence of his cultural heritage and the scars left by acts of segregation, prejudice, and racism. It is important for Mexican Americans to recognize that they are a unique group at a crossroads. They are not all…

  12. [Mexican migration policies after IRCA].

    Science.gov (United States)

    Alba, F

    1999-01-01

    The evolution since 1964 of Mexican government policy regarding migrant workers in the US is discussed. For a decade after the "bracero" program was terminated by the US, the Mexican government attempted to encourage creation of another legal framework for migration, regarded as inevitable whether legal or clandestine. Around 1974-75, a more distant attitude, termed the "policy of no policy," acquired considerable support in Mexican government and academic circles. The no-policy strategy allowed Mexico to achieve certain objectives regarding migration without prompting US intervention in its internal affairs, as for example by a linkage of US migration policy to specific Mexican government actions. The 1986 passage of the US Immigration Reform and Control Act effectively ended the no-policy strategy that had allowed the Mexican government to count on the continued emigration of Mexican workers without compromising its position of promoting respect for migrant rights. The unilateral change in the status quo by the US led to substitution of the "policy of dialogue," a clear signal of the Mexican government's search for a new migration agreement. The policy of dialogue has entailed greater discussion of the two traditional Mexican objectives regarding migration. Some progress has apparently been made concerning migrant rights, but the second and less explicit objective, that of preventing abrupt changes in US immigration policy and in migratory flows, is harder to judge. The atmosphere of freer public debate in Mexico is politicizing migratory policy.

  13. The Mexican Pension Annuity Market

    OpenAIRE

    Impavido, Gregorio

    2007-01-01

    This paper analyzes the performance and development of the Mexican pension annuity market established as a consequence of the 1997 pension reform. The Mexican experience displays interesting characteristics providing lessons for other countries that still need to design the decumulation phase of their newly established second pillars. At the same, time it raises some technical and policy c...

  14. Recovery of Salmonella enterica from seropositive finishing pig herds

    DEFF Research Database (Denmark)

    Wong, Danilo Lo Fo; Dahl, J.; van der Wolf, P.J.

    2003-01-01

    , apparent 'false-positive' serological results may well represent real infections not detected by bacteriological testing. For screening purposes, serological testing provides an indication of exposure to Salmonella, which forms the basis for targeted sampling, intervention and logistic slaughter procedures....... by the blood-sampling of 50 finishing pigs. Bacteriological sampling was performed by 20 pen faecal samples per herd. Over-all, 47% of the blood samples had an OD% larger than 10 and 23% larger than 40. Salmonella was isolated from 135 (9.3%) pen faecal samples in 32 herds (42%). Twenty-eight of these herds...

  15. Postweaning multisystematic wasting syndrome in Danish pig herds: productivity, clinical signs and pathology

    DEFF Research Database (Denmark)

    Okholm Nielsen, Elisabeth; Enøe, Claes; Jorsal, Sven Erik Lind;

    2008-01-01

    A case-control study of 74 herds with postweaning multisystemic wasting syndrome (PMWS) and 74 matched control herds was carried out. In the case herds the mortality rates of weaner and finisher pigs were 11·2 and 5·2 per cent respectively, compared with 3·1 and 3·2 per cent in the control herds....

  16. Post-weaning multisystemic wasting syndrome (PMWS) in Danish pig herds: productivity, clinical symptoms, and pathology

    DEFF Research Database (Denmark)

    Nielsen, E. Okholm; Enøe, Claes; Jorsal, Sven Erik Lind;

    2008-01-01

    A case-control study of 74 herds with postweaning multisystemic wasting syndrome (PMWS) and 74 matched control herds was carried out. In the case herds the mortality rates of weaner and finisher pigs were 11·2 and 5·2 per cent respectively, compared with 3·1 and 3·2 per cent in the control herds....

  17. Cow attributes, herd management, and reproductive history events associated with abortion in cow-calf herds from Western Canada.

    Science.gov (United States)

    Waldner, C L

    2014-04-01

    The primary objective of this study was to identify herd management and cow characteristics that are associated with abortion in cow-calf herds in Western Canada. Reproductive events were closely monitored in 29,713 cows in 203 herds from the beginning of the breeding season in 2001 through the calving season in 2002. Herd management and cow-level risk factors such as age, body condition score, and previous reproductive history were measured through a series of herd visits by project personnel and detailed individual animal records maintained by the herd owner. Pregnancy status was assessed in fall of 2001 by the herd veterinarian. Cows most likely to abort were replacement heifers, cows that were more than 10 years of age, cows with a body condition score of less than or equal to or 5 of 9 at pregnancy testing, or with twin pregnancies. Cows vaccinated for bovine viral diarrhea virus and infectious bovine rhinotracheitis and bred on community pastures were less likely to abort than cows from community pastures that were not vaccinated. Cows bred on community pastures that were not vaccinated were also more likely to abort than cows that were not on community pastures regardless of vaccination status. Adverse calving-associated events such as severe dystocia, problems such as uterine prolapse or retained placentas, abortion or calf death within 1 hour of birth were also associated with an increased risk of abortion the subsequent calving season after accounting for all other factors.

  18. [Herd immunity against poliomyelitis in children in the Moscow Region].

    Science.gov (United States)

    Seĭbil', V B; Malyshkina, L P; Tamazian, G V; Konopleva, T N; Uspenskaia, E S

    2009-01-01

    Herd immunity against poliomyelitis was studied in 1391 children and adolescents from 10 towns of the Moscow Region. It was ascertained that the values of herd immunity against poliomyelitis virus type 1 were high everywhere and those of herd immunity against poliomyelitis virus type 2 were high and very high in 9 towns and below the WHO minimum levels (80%). The values of herd immunity against poliomyelitis virus type 3; they were lower than the required minimum in 2 towns and very low in 2 other towns arouse alarm. The study of strain-specific antibodies to vaccine-derived and wild polioviruses has demonstrated that wild poliomyelitis viruses have not circulated in the areas of the examinees in the past decade.

  19. [Sullys Hill National Game Preserve bison herd raw data, 2006

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Raw data from Texas A&M University on the Sullys Hill National Game Preserve federal bison herd. Data includes nuclear introgression markers and nuclear...

  20. The state of knowledge of the Porcupine caribou herd

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This paper provides an assessment of the state of knowledge of the Porcupine Caribou Herd and its habitat, drawing on analogy with other studies where necessary. The...

  1. Surveillance of Mycobacterium avium subsp. paratuberculosis in dairy herds

    NARCIS (Netherlands)

    Weber, M.F.

    2009-01-01

    In this thesis, the potential for improvements in surveillance of Mycobacterium avium subsp. paratuberculosis (Map) infection and paratuberculosis in dairy herds was investigated, leading to a reduction in surveillance costs whilst continuing to meet specific quality targets. In particular, differen

  2. Jackson bison herd long term management plan and environmental assessment

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Free-ranging bison (Bison bison) were reintroduced to Jackson Hole from the Jackson Hole Wildlife Park in Grand Teton National Park in 1969. By March 1996, the herd...

  3. Applied epidemiology: another tool in dairy herd health programs?

    Science.gov (United States)

    Frankena, K; Noordhuizen, J P; Stassen, E N

    1994-01-01

    Data bases of herd health programs concern data from individual animals mainly. Several parameters that determine herd performance can be calculated from these programs, and by comparing actual values with standard values, areas for further improvement of health (and production) can be advised. However, such advice is usually not backed up by the proper statistical analyses. Moreover, data concerning the environment of the animals are not present and hence advice concerning multifactorial diseases are based on common knowledge and experience. Veterinary epidemiology offers methods that might improve the value of herd health programs by identification and quantification of factors and conditions contributing to multifactorial disease occurrence. Implementation of these methods within herd health programs will lead to more scientifically sound advice.

  4. Deer Herd Health Check dahomey National Wildlife Refuge 1997

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Report contains findings of deer herd health collection on Dahomey NWR in 1997. Deer appear to be in good health with no excess indication of parasite loading.

  5. Population dynamics of the Kaminuriak caribou herd, 1968 - 1985

    Directory of Open Access Journals (Sweden)

    Douglas C. Heard

    1986-06-01

    Full Text Available The Kaminuraik caribou herd apparently declined from about 120 000 animals in 1950 to 63 000 in 1968. Beginning in 1968 documentation of herd trend was based on the estimate of the number of breeding (pregnant and post-partum females on the calving ground during the birth peak. It appeared as if we understood the basic population processes responsible for the decline when we correctly predicted a drop from 14 800 breeding females in 1977 to 13 000 in 1980. However a three-fold increase, to 41 000 breeding females in 1982, and continued growth thereafter, was unanticipated. Most of that increase must have resulted from an immigration of cows to the herd's traditional calving ground around Kaminuriak Lake, although increased birth rates, and increased survival rates also contributed to herd growth. Immigrant cows probably came from the northeastern mainland of the NWT

  6. Genetic parameters for reproductive traits in a beef cattle herd ...

    African Journals Online (AJOL)

    Unknown

    a composite multibreed beef cattle herd using multitrait analysis. A REML procedure ... complex, CD and AFC (because of its high heritability) may be considered as selection criteria for ..... Marshall, D.M., Minqiang, W. & Freking, B.A., 1990.

  7. Modelling the effect of surveillance programmes on spread of bovine herpesvirus 1 between certified cattle herds.

    Science.gov (United States)

    Graat, E A; de Jong, M C; Frankena, K; Franken, P

    2001-04-02

    For the eradication of an infectious agent, like bovine herpesvirus 1 (BHV-1), surveillance and certification can be used to reduce the transmission between herds. The goal of surveillance is that a certified herd that becomes infected is detected timely so that infection of several other certified herds is prevented. What counts is whether the reproduction ratio R, i.e. the average number of certified herds infected by one infected certified herd can be kept below 1. To support policy makers in making decisions about the minimal demands for a surveillance programme in an eradication campaign of BHV-1 in cattle, two mathematical models were investigated. With these models, the basic reproduction ratio between herds was calculated. The surveillance programmes were characterised with sample size, sampling frequency, test sensitivity, herd size, vaccination status, and contacts between herds. When R between herds is below 1, then the surveillance programme is sufficiently good to prevent spread of infection, provided that R is estimated well. In the model based on bulk milk testing sample size was replaced by a threshold at which bulk milk can be found positive. The R between herds was mainly influenced by the vaccination status, sampling frequency, and contacts between herds. Herd size moderately affected the outcome. Test sensitivity and sample size, however, were of minor importance. If herds of 50 cows became free of BHV-1 without vaccination, then spread of infection between herds might be prevented when animals within herds are sampled once a year (milk or blood samples). This frequency needs to be intensified, being twice a year, for larger herds and/or herds with extensive contacts with other herds. When bulk milk is sampled instead, sampling should be done at least every 5 months and more intensively, being each month, with larger herd sizes and more contacts between herds.

  8. Effects of concentrate level and rapeseed meal supplementation on performance, carcass characteristics, meat quality and valuable cuts of Hereford and Charolais bulls offered grass silage-barley-based rations

    Directory of Open Access Journals (Sweden)

    Maiju Pesonen

    2013-03-01

    Full Text Available The objectives of this experiment with Hereford (Hf and Charolais (Ch bulls offered grass silage-based diets were to determine the effects on performance, carcass traits and meat quality of the proportion of concentrate in the diet, and the inclusion of rapeseed meal (RSM in the barley-based concentrate. The two concentrate proportions were 200 and 500 g kg-1 dry matter, fed without or with RSM. The Ch bulls tended to achieve higher gain, produced less fat, had a higher percentage of meat from high-priced joints and had a lower degree of marbling in their meat compared to the Hf bulls. Dry matter and energy intakes, growth performance and carcass conformation improved with increasing concentrate level. Intake parameters and conformation improved more with the Ch bulls than with the Hf bulls as a consequence of increased concentrate allowance. RSM had only limited effects on the performance, carcass traits or meat quality.

  9. [The PRRSV-serumneutralization test detects gaps in herd immunity].

    Science.gov (United States)

    Böttcher, Jens; Alex, Michaela; Janowetz, Britta; Müller, Silvia; Schuh, Christina; Niemeyer, Hermann

    2014-01-01

    Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) appears in two genotypes (EU and US), for both genotypes attenuated live-vaccines are available. A cross-sectional study in 38 Bavarian sow herds was performed to assess the level of neutralizing antibodies. Per herd 38 blood samples were collected (10 weaned piglets, 10 gilts and 6 sows of 1./2., 3J4. and 5/6. parity, respectively). Sera were tested by ELISA, serumneutralization test (SNT) against EU- and US-vaccine virus, and pooled sera were tested by real-time RT-PCR. Herds were classified by the last vaccination of sows as "Vacc EU" "Vacc US"and "nv (non-vaccinated) and by detection of PRRSV-US and vaccination of piglets were not included as variables. Sows of group (2) Vacc EU/EU- showed the highest EU-SNT-titers irrespective of parity. Groups (5) Vacc US/EU+ and (1) Vacc EU/EU+ followed in descending order. Significantly lower SNT-titers in (1) Vacc EU/EU+ were especially observed in sows of 1/2. Parity (Kruskal-Wallis, p herds detection of PRRSV-EU coincided with strong ELISA-reactivity in all animal groups. In EU-vaccinated herds this was only observed for weaned piglets. Sows showed a strong ELISA-reactivity irrespective of detection of PRRSV-EU. The value of the ELISA is restricted to the certification of PRRSV-free herds. The EU-SNT reflects the level of herd immunity at least against vaccine virus; it indicates gaps in herd immunity.

  10. The Hardangervidda wild reindeer herd: a problematic management history

    Directory of Open Access Journals (Sweden)

    Dag K. Bjerketvedt

    2014-05-01

    Full Text Available The unique and internationally important wild reindeer Rangifer tarandus herd on the Hardangervidda plateau of southern Norway  has shown frequent and extreme fluctuations in harvest numbers for the past 60 years, despite considerable effort to stabilize the herd size at a winter carrying capacity of  9000 – 12 000 animals . In the absence of large mammalian predators, herd size is managed through hunting.  Here we attempt to unravel the causes of the management problems related to this population by examining the relative roles of historical, biological and management-related processes. From 1900 - 1950 the population remained mainly low due to a combination of generous harvest quotas, poaching and competition from domestic reindeer.  From 1950 - 2012 three extreme harvest peaks of between 4500 - 9500 animals occurred, followed by three equally extreme troughs including two shorter periods of total protection.  This extreme harvest fluctuation contrasts with the estimated annual harvest of 2300 - 3000 needed to stabilize the winter herd between 9000 - 12 000 animals.  We conclude that this population has been difficult to manage mainly because of 1 a management based on frequently unreliable population data on herd size (especially before 2001, 2 lack of  in depth analyses and evaluation of both recruitment and sex and age composition and 3 a low and highly variable harvest success (harvest/quota due mainly to poor hunter mobility, a disadvantage when reindeer must be harvested from large flocks that constantly move upwind, seeking refuge on small areas with few hunters.  More reliable population data to create better harvest models plus increased hunter mobility are necessary to attain a more sustainable herd size, implying an improvement of the current herd survey methodology available to local reindeer boards.  Finally, a critical and independent evaluation of the scientific methodology employed to study and manage this herd is

  11. Evaluation of observed parameters of a beef herd.

    OpenAIRE

    CIMBURKOVÁ, Pavla

    2008-01-01

    It has been observed beef breed herd of Aberdeen Angus cattle in the foothills area of Novohradské mountains in 1992 - 2007. The base of herd was consisted of 117 dams and 814 pieces of calves in total. The parameters of beef production of calves and the reproduction of dams were monitored. For the parameters of growth of calves were found significant effects of the year, the month of birth, sex, the order of calving, the method of reproduction and the sire.

  12. Herd Immunity: A Realistic Goal for Elimination of Communicable Diseases

    Directory of Open Access Journals (Sweden)

    Saurabh RamBihariLal Shrivastava

    2014-04-01

    Full Text Available The benefits of immunization programs are beyond prevention of specific diseases in individuals. Efficacious vaccine not only protects the immunized, but also extends their benefits to unimmunized individuals of the community through and #8220;herd protection and #8221; or and #8220;herd immunity and #8221;. Herd immunity is the basis on which all national immunization programs are designed. It is defined as the resistance of a group of people to an attack by a disease to which a large proportion of the members of the group are immune. The percentage of the population that must however be immunized depends on three factors: the infectivity of the disease, the vulnerability of the population, and environmental factors. The aim of herd immunity is to reduce effective reproduction rate to less than 1 for each disease thus barring the disease propagation in community. Herd immunity has been found to be effective in multiple respiratory and diarrheal diseases. To conclude, no vaccine offers complete protection, but the spread of disease from person-to-person is much higher in those who remain unvaccinated. Herd immunity can definitely protect the susceptible individuals from acquiring the infection if the numbers of immunized individual are above the threshold level. It is an achievable goal for majority of the communicable diseases and all efforts should be taken by the program managers to amplify it in the community. [TAF Prev Med Bull 2014; 13(2.000: 187-188

  13. Success and failure of reindeer herding in Greenland

    Directory of Open Access Journals (Sweden)

    Christine Cuyler

    1999-04-01

    Full Text Available Animal husbandry is a recent innovation in Greenland, specifically reindeer husbandry is less than 50 years old. Reindeer husbandry was first established in mid-west Greenland and later in southern Greenland. The Greenland hunter tradition and culture is, however, still dominant in many communities. During the 1980s and 1990s, the incompatibility of these two traditions resulted in the failure of reindeer husbandry in mid-west Greenland. There were neither herding nor seasonal herd movements. Animals remained year round on the winter range, which was destroyed as lichens were trampled every summer. Without seasonal herd movements both sustainable range use and control of the herd were lost. Today, there are just two semi-domestic reindeer herds left, and both are in southern Greenland. One herd is commercially successful, and the other is under development. In mid-west Greenland, semi-domestic reindeer husbandry officially ended in 1998, and a hunt was initiated to remove the remaining population. Possibly, by the year 2000 any animals left in this region will be considered wild caribou.

  14. Markets, Herding and Response to External Information.

    Science.gov (United States)

    Carro, Adrián; Toral, Raúl; San Miguel, Maxi

    2015-01-01

    We focus on the influence of external sources of information upon financial markets. In particular, we develop a stochastic agent-based market model characterized by a certain herding behavior as well as allowing traders to be influenced by an external dynamic signal of information. This signal can be interpreted as a time-varying advertising, public perception or rumor, in favor or against one of two possible trading behaviors, thus breaking the symmetry of the system and acting as a continuously varying exogenous shock. As an illustration, we use a well-known German Indicator of Economic Sentiment as information input and compare our results with Germany's leading stock market index, the DAX, in order to calibrate some of the model parameters. We study the conditions for the ensemble of agents to more accurately follow the information input signal. The response of the system to the external information is maximal for an intermediate range of values of a market parameter, suggesting the existence of three different market regimes: amplification, precise assimilation and undervaluation of incoming information.

  15. Markets, Herding and Response to External Information.

    Directory of Open Access Journals (Sweden)

    Adrián Carro

    Full Text Available We focus on the influence of external sources of information upon financial markets. In particular, we develop a stochastic agent-based market model characterized by a certain herding behavior as well as allowing traders to be influenced by an external dynamic signal of information. This signal can be interpreted as a time-varying advertising, public perception or rumor, in favor or against one of two possible trading behaviors, thus breaking the symmetry of the system and acting as a continuously varying exogenous shock. As an illustration, we use a well-known German Indicator of Economic Sentiment as information input and compare our results with Germany's leading stock market index, the DAX, in order to calibrate some of the model parameters. We study the conditions for the ensemble of agents to more accurately follow the information input signal. The response of the system to the external information is maximal for an intermediate range of values of a market parameter, suggesting the existence of three different market regimes: amplification, precise assimilation and undervaluation of incoming information.

  16. How can social herding enhance cooperation?

    CERN Document Server

    Schweitzer, Frank; Tessone, Claudio J

    2012-01-01

    We study a system in which N agents have to decide between two strategies \\theta_i (i \\in 1... N), for defection or cooperation, when interacting with other n agents (either spatial neighbors or randomly chosen ones). After each round, they update their strategy responding nonlinearly to two different information sources: (i) the payoff a_i(\\theta_i, f_i) received from the strategic interaction with their n counterparts, (ii) the fraction f_i of cooperators in this interaction. For the latter response, we assume social herding, i.e. agents adopt their strategy based on the frequencies of the different strategies in their neighborhood, without taking into account the consequences of this decision. We note that f_i already determines the payoff, so there is no additional information assumed. A parameter \\zeta defines to what level agents take the two different information sources into account. For the strategic interaction, we assume a Prisoner's Dilemma game, i.e. one in which defection is the evolutionary sta...

  17. Markets, Herding and Response to External Information

    Science.gov (United States)

    Carro, Adrián; Toral, Raúl; San Miguel, Maxi

    2015-01-01

    We focus on the influence of external sources of information upon financial markets. In particular, we develop a stochastic agent-based market model characterized by a certain herding behavior as well as allowing traders to be influenced by an external dynamic signal of information. This signal can be interpreted as a time-varying advertising, public perception or rumor, in favor or against one of two possible trading behaviors, thus breaking the symmetry of the system and acting as a continuously varying exogenous shock. As an illustration, we use a well-known German Indicator of Economic Sentiment as information input and compare our results with Germany’s leading stock market index, the DAX, in order to calibrate some of the model parameters. We study the conditions for the ensemble of agents to more accurately follow the information input signal. The response of the system to the external information is maximal for an intermediate range of values of a market parameter, suggesting the existence of three different market regimes: amplification, precise assimilation and undervaluation of incoming information. PMID:26204451

  18. Bayesian estimation of true between-herd and within-herd prevalence of Salmonella in Danish veal calves

    DEFF Research Database (Denmark)

    Nielsen, Torben Dahl; Nielsen, Liza Rosenbaum; Toft, Nils

    2011-01-01

    Specialised veal producers that purchase and raise calves from several dairy herds are potentially at high risk of delivering Salmonella-infected animals to slaughter. However, the true prevalence of Salmonella infected veal producing herds and the prevalence of infected calves delivered...... six of 68 herds obtaining posterior probability of being infected less than 10%. Furthermore, this study indicated that serology is sufficiently sensitive and specific to be used for estimating the prevalence of Salmonella-infected specialised veal producing herds....

  19. Cow- and herd-level risk factors for on-farm mortality in Midwest US dairy herds.

    Science.gov (United States)

    Shahid, M Q; Reneau, J K; Chester-Jones, H; Chebel, R C; Endres, M I

    2015-07-01

    The objectives of this study were to describe on-farm mortality and to investigate cow- and herd-level risk factors associated with on-farm mortality in Midwest US dairy herds using lactation survival analysis. We analyzed a total of approximately 5.9 million DHIA lactation records from 10 Midwest US states from January 2006 to December 2010. The cow-level independent variables used in the models were first test-day milk yield, milk fat percent, milk protein percent, fat-to-protein ratio, milk urea nitrogen, somatic cell score, previous dry period, previous calving interval, stillbirth, calf sex, twinning, calving difficulty, season of calving, parity, and breed. The herd-level variables included herd size, calving interval, somatic cell score, 305-d mature-equivalent milk yield, and herd stillbirth percentage. Descriptive analysis showed that overall cow-level mortality rate was 6.4 per 100 cow-years and it increased from 5.9 in 2006 to 6.8 in 2010. Mortality was the primary reason of leaving the herd (19.4% of total culls) followed by reproduction (14.6%), injuries and other (14.0%), low production (12.3%), and mastitis (10.5%). Risk factor analysis showed that increased hazard for mortality was associated with higher fat-to-protein ratio (>1.6 vs. 1 to 1.6), higher milk fat percent, lower milk protein percent, cows with male calves, cows carrying multiple calves, higher milk urea nitrogen, increasing parity, longer previous calving interval, higher first test-day somatic cell score, increased calving difficulty score, and breed (Holstein vs. others). Decreased hazard for mortality was associated with higher first test-day milk yield, higher milk protein, and shorter dry period. For herd-level factors, increased hazard for mortality was associated with increased herd size, increased percentage of stillbirths, higher somatic cell score, and increased herd calving interval. Cows in herds with higher milk yield had lower mortality hazard. Results of the study

  20. Herd size and sero-prevalence of Salmonella enterica in Danish swine herds: a random-effects model for register data

    DEFF Research Database (Denmark)

    Carstensen, Bendix; Christensen, Jette

    1998-01-01

    The association between herd size and sero-prevalence of Salmonella was assessed in a random-effects model with herd size, county and date of slaughter as fixed effects. A total of 510915 meat-juice samples from 14593 herds located in 13 counties in Denmark was included in the study. A random-eff...

  1. Relationship between leukocyte population and nutritive conditions in dairy herds with frequently appearing mastitis.

    Science.gov (United States)

    Ohtsuka, Hiromichi; Kohiruimaki, Masayuki; Hayashi, Tomohito; Katsuda, Ken; Matsuda, Kei-ichi; Masui, Machiko; Abe, Ryo; Kawamura, Sei-ichi

    2006-02-01

    To clarify the relationship between cellular immune status and nutritive condition, feeding program, blood profiles, and leukocyte populations were analyzed in two dairy herds experiencing frequent mastitis. Fourteen of the 35 lactating cows in herd A, and 18 of the 50 lactating cows in herd B scored positive on the California Mastitis Test (CMT), and 3 of the 73 lactating cows were CMT positive in herd C, which was the control. All herds were evaluated during five different milking stages, and blood was collected from five cows at each stage. With regard to feed content, the percentages of total digestible nutrients (TDN) and crude protein (CP) were found to be lower in herds A and B than in herd C. Levels of serum total cholesterol and blood urea nitrogen were lower in herds A and B than those in herd C. Neutrophil counts in herds A and B were increased compared to the neutrophil counts in herd C. On the other hand, the numbers of CD3(+) T cells and CD14-MHC class(+) cells were lower in herd A and B than in herd C. A decrease in peripheral lymphocytes and undernourishment were observed in the herds with frequent occurring mastitis.

  2. Infectious reproductive disease pathogens in dairy herd bulls.

    Science.gov (United States)

    Hancock, A S; Younis, P J; Beggs, D S; Mansell, P D; Pyman, M F

    2015-10-01

    Investigate the presence of infectious reproductive disease pathogens in dairy herd bulls in south-west Victoria, Australia, using a cross-sectional study. Dairy herd bulls from 32 herds were sampled for bovine viral diarrhoea virus (BVDV: 256 bulls, 32 herds) prior to the natural mating period, bovine herpes virus-1 prior to (10 bulls, 5 herds) and after (118 bulls, 19 herds) the natural mating period, and for Campylobacter fetus spp. and Tritrichomonas foetus after the natural mating period (61 bulls, 7 herds). BVDV was detected from an ear-notch sample using a commercially available rapid assay ELISA, bovine herpes virus-1 and T. foetus were screened for by PCR from a penile swab and preputial sample respectively, and C. fetus spp. were screened for by culture of preputial samples. None of the bulls tested positive for BVDV antigen. Campylobacter fetus venerealis (or C. fetus fetus) was cultured in 6.6% (4/61) of bulls, representing 2 of the 7 (28.6%) farms that were not vaccinating bulls against bovine genital campylobacteriosis. Bovine herpes virus-1 was identified in 7.8% (10/128) bulls sampled; T. foetus was not identified in any samples. Bovine genital campylobacteriosis is present in south-western Victoria, despite longstanding recommendations to vaccinate bulls. Screening bulls for persistent infection with BVDV is probably justified, despite the absence of persistently infected bulls in this study. Further research is warranted to investigate the potential reproductive implications of BHV-1, and the presence of T. foetus. © 2015 Australian Veterinary Association.

  3. Freud's Mexican readers.

    Science.gov (United States)

    Gallo, Rubén

    2011-01-01

    This essay presents an overview of artists and writers who read Freud's work in Mexico between 1920 and 1968. The focus is on cultural readings of Freud: non-clinical interpretations of psychoanalysis that applied Freud's theory to literary, artistic, philosophical, or religious questions. The essay focuses on Salvador Novo, one of the poets associated with the Contemporáneos group, and his reading of the "Three Essays in the Theory of Sexuality;" Raúl Carrancá y Trujillo, a judge and criminologist who used psychoanalysis in his work, including the trial of Trotky's assassin; Octavio Paz, a poet and intellectual who wrote an essay on Mexican history, "The Labyrinth of Solitude," as a response to "Moses and Monotheism;" and Gregorio Lemercier, a Benedictine monk who placed his monastery in group analysis. These unorthodox readings of Freud opened the door for some of the most daring intellectual experiments in the 20th century.

  4. Herd size and sero-prevalence of Salmonella enterica in Danish swine herds: a random-effects model for register data

    DEFF Research Database (Denmark)

    Carstensen, Bendix; Christensen, Jette

    1998-01-01

    The association between herd size and sero-prevalence of Salmonella was assessed in a random-effects model with herd size, county and date of slaughter as fixed effects. A total of 510915 meat-juice samples from 14593 herds located in 13 counties in Denmark was included in the study. A random......-effects model was developed from separate models for smaller strata of data from herds with approximately equal sizes. The combined model was analysed and the results reported. Herd size was positively associated with the sere-prevalence of Salmonella enterica, but the size of the association was biologically...

  5. Herd-level interpretation of test results for epidemiologic studies of animal diseases

    DEFF Research Database (Denmark)

    Christensen, Jette; Gardner, Ian A.

    2000-01-01

    Correct classification of the true status of herds is an important component of epidemiologic studies and animal disease-control programs. We review theoretical aspects of herd-level testing through consideration of test performance (herd-level sensitivity, specificity and predictive values......), the factors affecting these estimates, and available software for calculations. We present new aspects and considerations concerning the effect of precision and bias in estimation of individual-test performance on herd-test performance and suggest methods (pooled testing, targeted sampling of subpopulations...... with higher prevalence, and use of combinations of tests) to improve herd-level sensitivity when the expected within-herd prevalence is low....

  6. Predicting the level of herd infection for outbreaks of foot-and-mouth disease in vaccinated herds.

    Science.gov (United States)

    Hutber, A M; Kitching, R P; Conway, D A

    1999-06-01

    Foot-and-mouth disease (FMD) is a highly contagious virus infection of sheep, goats, cattle, pigs and other, non-domesticated species of artiodactyls, and causes both clinical and subclinical infection according to the natural or acquired immunity of the host. Within vaccinated dairy herds FMD may appear as an acute, mild or subclinical infection, dependent upon the immune status of the herd, the level of challenge and the efficacy of the vaccine used. In the large dairy herds of Saudi Arabia, sub-clinical FMD was on a number of occasions, found to have spread amongst the cattle before signs of disease were seen. Such undetected transmission resulted in a large incidence on the first day of diagnosis and curtailed the impact of post-outbreak vaccination (PoV). First day incidence (FDI) for these herds was found to correlate with the final cumulative incidence of clinical disease. Since FDI is available at the start of an outbreak it can be used as a predictive tool for the eventual outcome of an FMD outbreak. During the past 11 years 47 % of dairy herds examined in Saudi Arabia have experienced FMD initially as sub-clinical disease. For the remaining 53 %, waning vaccinal protection did not suppress clinical disease in the initially infected animals, and these showed severe rather than mild signs. Hence, in such herds there was a very low initial level of subclinical infection, so PoV was more effective, and the timing of PoV was found to give a good correlation with cumulative herd incidence: an early PoV resulted in low prevalence of clinically infected animals whilst late PoV permitted high prevalence. PoV timing can thereby be used in tandem with FDI as a predictive tool for future outbreaks, estimating the final cumulative incidence (or prevalence) of clinical FMD cases.

  7. Pyrantel resistance in two herds of donkey in the UK.

    Science.gov (United States)

    Lawson, Edwina; Burden, Faith; Elsheikha, Hany M

    2015-01-30

    Resistance to currently available anthelmintics is a serious phenomenon which is prevalent globally. Cyathostomins are one of the major parasites, and are of primary concern in donkeys. There have been reports of emerging resistance to pyrantel, but the status of pyrantel resistance in donkey populations in the UK is largely unknown. This report investigates pyrantel resistance in two geographically isolated donkey herds in the South West of England. The first herd had suspected pyrantel resistance, with already established resistance to other anthelmintics. In the second herd the efficacy of pyrantel was not suspected at the time the study took place. Faecal Egg Count Reduction Test (FECRT) was carried out, revealing large scale resistance. Eighty one percent of the first herd and 73% of the second herd had a FEC of less than 95% after treatment, and anthelmintic resistance was confirmed using the World Association for the Advancement of Veterinary Parasitology guidelines. These findings indicate that anthelmintic resistance to pyrantel exists in both tested donkey populations and illustrate the continuing development of resistance through different classes of chemotherapeutics.

  8. Aetiology of clinical mastitis in six Somerset dairy herds.

    Science.gov (United States)

    Bradley, A J; Green, M J

    2001-06-02

    Clinical mastitis was monitored in six Somerset dairy herds for one year. The herds all had three-month geometric mean bulk milk somatic cell counts of less than 250,000 cells/ml. Escherichia coli was the predominant pathogen isolated on all the farms and in all months of the year. Environmental pathogens accounted for 61.4 per cent of all cases of clinical mastitis and for 79.3 per cent of the mastitis cases in which an aetiological agent was identified. The mean annual incidence was 41.6 cases per 100 cows (range 14 to 75). Affected cows suffered a mean of 1.5 cases and 16.4 per cent of quarters suffered at least one repeat case. Mastitis due to E. coli was more severe than mastitis due to other causes and it tended to be more severe in early lactation and during the housing period. Mastitis was significantly more severe (grades 2 and 3) in the herd with the lowest bulk milk somatic cell count and in the herd which was kept indoors throughout the year than in the other four herds. Mastitis was fatal in 2.2 per cent of cases and resulted in the death of 0.6 per cent of the lactating cows.

  9. Why herd size matters - mitigating the effects of livestock crashes.

    Directory of Open Access Journals (Sweden)

    Marius Warg Næss

    Full Text Available Analysing the effect of pastoral risk management strategies provides insights into a system of subsistence that have persevered in marginal areas for hundreds to thousands of years and may shed light into the future of around 200 million households in the face of climate change. This study investigated the efficiency of herd accumulation as a buffer strategy by analysing changes in livestock holdings during an environmental crisis in the Saami reindeer husbandry in Norway. We found a positive relationship between: (1 pre- and post-collapse herd size; and (2 pre-collapse herd size and the number of animals lost during the collapse, indicating that herd accumulation is an effective but costly strategy. Policies that fail to incorporate the risk-beneficial aspect of herd accumulation will have a limited effect and may indeed fail entirely. In the context of climate change, official policies that incorporate pastoral risk management strategies may be the only solution for ensuring their continued existence.

  10. [Eradication of Prototheca zopfii infection in a dairy cattle herd].

    Science.gov (United States)

    Rösler, U; Hensel, A

    2003-09-01

    Protothecosis is a severe form of mastitis in dairy cows caused by colorless algae of the genus Prototheca. Since P. zopfii is highly resistant to all known chemotherapeutics, infected cows must be removed from the herd. Eradication measures are difficult since many chronically infected cows may become intermittent shedders. Therefore, cultural methods are insufficient for control measures. In order to eradicate Prototheca zopfii-mastitis in dairy cattle herds, two isotype specific indirect ELISA for detection of IgA and IgG1 in whey were used in a dairy herd highly affected with protothecal mastitis. All cows (n = 313) were tested four times in intervals of six months. Milk specimens were examined in parallel by cultivation and serologically using two indirect ELISA systems for specific IgA and IgG1 in whey. Cows tested Prototheca positive were consequently separated from the herd and slaughtered. At the first examination, 15.6% of the animals were found positive by culture, and 23.3% were positive in at least one of the ELISA systems. Within two years, protothecal prevalence and incidence decreased to zero indicating that the eradication strategy used was successful. In summary, serological identification of P. zopfii-infected lactating cows is an useful tool to eradicate protothecal bovine mastitis in infected herds.

  11. Modeling growth of mandibles in the Western Arctic caribou herd

    Directory of Open Access Journals (Sweden)

    Jay M. Ver Hoef

    2001-03-01

    Full Text Available We compared growth curves for ramus length and diastema length from two autumn collections of mandibles of male Western Arctic Herd caribou in Alaska. We were primarily interested in determining if growth curves of caribou mandibles differed between caribou born during 1959-1967, after the herd had been high for several years and was probably declining in size, and those born during 1976-1988, when the herd was increasing in size. To compare these growth curves, we used a nonlinear model and used maximum likelihood estimates and likelihood ratio tests. We found that growth rates were similar between periods, but intercepts and variances of growth curves differed. From this we infer that calves were smaller in autumn during the 1960s and that significant compensatory growth did not occur later in life.

  12. Infection dynamics of Lawsonia intracellularis in pig herds

    DEFF Research Database (Denmark)

    Stege, H.; Jensen, Tim Kåre; Møller, Kristian

    2004-01-01

    Little information is known about the natural course and within-herd prevalence of porcine proliferative enteropathy caused by Lawsonia intracellularis. The objective of the study was to investigate the within-herd dynamics of naturally acquired L. intracellularis infection in pigs from weaning...... shedding of L. intracellularis was assessed by real time-PCR and sero-conversion by an indirect immunofluorescence antibody test (IFAT). Clinical disease was not reported but infection was present in all herds and the PCR assay indicated infection in 75% of pigs examined. Most L. intracellularis infected...... pigs were shedding at 10-12 weeks of age (22-29 kg) and shed for 2-6 successive weeks. After 18 weeks of age all shedding had ceased and re-infection at PCR detectable level was not seen. Variable L. intracellularis associated impact on growth rate was observed. Immediately before bacterial shedding...

  13. Mexican-American Women: Diversity in Depth.

    Science.gov (United States)

    Weaver, Marleen E.

    Various literary views of the Mexican American woman have been presented over the past 150 years. Anglo treatment of Mexican American women in literature has varied from blatant prejudice or vague mystical eroticism in early portrayals to more realistic views of the Chicano in modern writing. The current identity crisis of Mexican Americans is…

  14. Mexican-American Cultural Assumptions and Implications.

    Science.gov (United States)

    Carranza, E. Lou

    The search for presuppositions of a people's thought is not new. Octavio Paz and Samuel Ramos have both attempted to describe the assumptions underlying the Mexican character. Paz described Mexicans as private, defensive, and stoic, characteristics taken to the extreme in the "pachuco." Ramos, on the other hand, described Mexicans as…

  15. Mexican-American Cultural Assumptions and Implications.

    Science.gov (United States)

    Carranza, E. Lou

    The search for presuppositions of a people's thought is not new. Octavio Paz and Samuel Ramos have both attempted to describe the assumptions underlying the Mexican character. Paz described Mexicans as private, defensive, and stoic, characteristics taken to the extreme in the "pachuco." Ramos, on the other hand, described Mexicans as…

  16. El Arte Culinario Mexicano (Mexican Culinary Art).

    Science.gov (United States)

    Card, Michelle

    This unit in Mexican cooking can be used in Junior High School home economics classes to introduce students to Mexican culture or as a mini-course in Spanish at almost any level. It is divided into two parts. Part One provides historical background and information on basic foods, the Mexican market, shopping tips, regional cooking and customs.…

  17. 47 CFR 22.957 - Mexican condition.

    Science.gov (United States)

    2010-10-01

    ... 47 Telecommunication 2 2010-10-01 2010-10-01 false Mexican condition. 22.957 Section 22.957... Cellular Radiotelephone Service § 22.957 Mexican condition. Pursuant to an agreement between the United... States-Mexican border must have the following condition attached: This authorization is subject to...

  18. El Arte Culinario Mexicano (Mexican Culinary Art).

    Science.gov (United States)

    Card, Michelle

    This unit in Mexican cooking can be used in Junior High School home economics classes to introduce students to Mexican culture or as a mini-course in Spanish at almost any level. It is divided into two parts. Part One provides historical background and information on basic foods, the Mexican market, shopping tips, regional cooking and customs.…

  19. Study on the Measures of Connectedness Between Herds

    Institute of Scientific and Technical Information of China (English)

    ZHANG Hao; LIU Xiao-hong; WANG Chong; LI Jia-qi; CHEN Yao-sheng

    2004-01-01

    Pig breeding is generally conducted among many herds, so EBV comparisons across populations are necessary. Genetic connectedness is required for reliable between-farmanimal EBV comparisons.Five quantitative overall connectedness measures among populations have been proposed so far,coefficient of connectedness(γ*), coefficient of determination (CD) and overall indices of precision, connectedness rating, number of direct genetic links between subpopulations due to common sires and dams (GLt), and average genetic covariance (AGC) are reviewed and theirproperties are discussed in this paper. It is recommended to use AGC at present for measuring genetic connectedness between herds.

  20. Stochastic models to simulate paratuberculosis in dairy herds

    DEFF Research Database (Denmark)

    Nielsen, S.S.; Weber, M.F.; Kudahl, Anne Margrethe Braad

    2011-01-01

    Stochastic simulation models are widely accepted as a means of assessing the impact of changes in daily management and the control of different diseases, such as paratuberculosis, in dairy herds. This paper summarises and discusses the assumptions of four stochastic simulation models and their use...... the models are somewhat different in their underlying principles and do put slightly different values on the different strategies, their overall findings are similar. Therefore, simulation models may be useful in planning paratuberculosis strategies in dairy herds, although as with all models caution...

  1. Invited review: Artisanal Mexican cheeses.

    Science.gov (United States)

    González-Córdova, Aarón F; Yescas, Carlos; Ortiz-Estrada, Ángel Martín; De la Rosa-Alcaraz, María de Los Ángeles; Hernández-Mendoza, Adrián; Vallejo-Cordoba, Belinda

    2016-05-01

    The objective of this review is to present an overview of some of the most commonly consumed artisanal Mexican cheeses, as well as those cheeses that show potential for a protected designation of origin. A description is given for each of these cheeses, including information on their distinguishing characteristics that makes some of them potential candidates for achieving a protected designation of origin status. This distinction could help to expand their frontiers and allow them to become better known and appreciated in other parts of the world. Due to the scarcity of scientific studies concerning artisanal Mexican cheeses, which would ultimately aid in the standardization of manufacturing processes and in the establishment of regulations related to their production, more than 40 varieties of artisanal cheese are in danger of disappearing. To preserve these cheeses, it is necessary to address this challenge by working jointly with government, artisanal cheesemaking organizations, industry, academics, and commercial partners on the implementation of strategies to protect and preserve their artisanal means of production. With sufficient information, official Mexican regulations could be established that would encompass and regulate the manufacture of Mexican artisanal cheeses. Finally, as many Mexican artisanal cheeses are produced from raw milk, more scientific studies are required to show the role of the lactic acid bacteria and their antagonistic effect on pathogenic microorganisms during aging following cheese making.

  2. Nation-wide Salmonella enterica surveillance and control in Danish slaughter swine herds

    DEFF Research Database (Denmark)

    Mousing, Jan; Jensen, P.T.; Halgaard, C.

    1997-01-01

    A nation-wide Salmonella enterica surveillance and control programme was initiated in Danish finishing herds over the first quarter of 1995, In Denmark, all swine for slaughter are identifiable by a unique herd code. For each herd code, and depending on the herd's annual kill, random samples...... ranging from four to more than 60 swine are obtained quarterly at the abattoir. A meat sample from each pig is frozen, and meat juice (harvested after thawing) is examined for specific antibodies against S. enterica using an indirect enzyme-linked immunosorbent assay (ELISA). The ELISA combines several S.......0% of the total kill. In December 1995, 15 522 herds (representing > 90% of the national production) were categorized into one of the three levels: 14 551 herds (93.7%) in Level 1; 610 herds (3.9%) in Level 2; 361 herds (2.3%) in Level 3. The proportion of serologically positive meat-juice samples collected...

  3. Eradication of bovine tuberculosis at a herd-level in Madrid, Spain: study of within-herd transmission dynamics over a 12 year period

    Directory of Open Access Journals (Sweden)

    Alvarez Julio

    2012-06-01

    Full Text Available Abstract Background Eradication of bovine tuberculosis (bTB through the application of test-and-cull programs is a declared goal of developed countries in which the disease is still endemic. Here, longitudinal data from more than 1,700 cattle herds tested during a 12 year-period in the eradication program in the region of Madrid, Spain, were analyzed to quantify the within-herd transmission coefficient (β depending on the herd-type (beef/dairy/bullfighting. In addition, the probability to recover the officially bTB free (OTF status in infected herds depending on the type of herd and the diagnostic strategy implemented was assessed using Cox proportional hazard models. Results Overall, dairy herds showed higher β (median 4.7 than beef or bullfighting herds (2.3 and 2.2 respectively. Introduction of interferon-gamma (IFN-γ as an ancillary test produced an apparent increase in the β coefficient regardless of production type, likely due to an increase in diagnostic sensitivity. Time to recover OTF status was also significantly lower in dairy herds, and length of bTB episodes was significantly reduced when the IFN-γ was implemented to manage the outbreak. Conclusions Our results suggest that bTB spreads more rapidly in dairy herds compared to other herd types, a likely cause being management and demographic-related factors. However, outbreaks in dairy herds can be controlled more rapidly than in typically extensive herd types. Finally, IFN-γ proved its usefulness to rapidly eradicate bTB at a herd-level.

  4. Pathogen-specific incidence rate of clinical mastitis in Flemish dairy herds, severity, and association with herd hygiene.

    Science.gov (United States)

    Verbeke, Joren; Piepers, Sofie; Supré, Karlien; De Vliegher, Sarne

    2014-11-01

    A one-year survey on clinical mastitis was conducted on 50 randomly selected commercial Flemish dairy herds to estimate the pathogen-specific incidence rate of clinical mastitis (IRCM). The severity of the cases and the potential associations with herd hygiene were studied. Participating producers sampled 845 cases and 692 dairy cows. The mean and median IRCM was estimated at 7.4 and 5.3 quarter cases per 10,000 cow-days at risk, respectively. A large between-herd variation was observed (range of 0-21.3). In general, the IRCM was lower in heifers compared with multiparous cows (2.9 vs. 11.0 quarter cases per 10,000 cow-days at risk). However, the overall IRCM in the first week after calving was higher in heifers compared with cows (43.4 vs. 31.6 quarter cases per 10,000 cow-days at risk). Streptococcus uberis (18.2% of the cases) and Escherichia coli (15.5%) were the most frequently isolated pathogens and no growth was observed in 19.9% of the cases. The majority of the cases (63.1%) were mild (only clots in milk). Moderate (hard quarter without general signs) and severe symptoms (systemic illness) were observed in 29.9 and 7.0% of the cases, respectively. Isolation of E. coli (vs. any other culture result) was more likely in moderate and severe cases compared with mild cases. Overall IRCM and E. coli IRCM were higher in dirty compared with clean herds based on udder hygiene scores (9.0 and 1.7 vs. 6.0 and 0.6 quarter cases per 10,000 cow-days at risk, respectively). This study broadens the knowledge on clinical mastitis in Flemish dairy herds and underlines the high risk of CM in early-lactation heifers, the role of the so-called environmental pathogens, and herd hygiene.

  5. Relação entre genótipos e temperamento de novilhos Charolês x Nelore em confinamento Relations among genotypes and temperament of Charolais x Nellore steers in confinement

    Directory of Open Access Journals (Sweden)

    Isabella Dias Barbosa Silveira

    2008-10-01

    Full Text Available Avaliou-se a influência da interação entre genótipos e do temperamento de bovinos sobre os ganhos diretos e indiretos para a produção de carne. Utilizaram-se 79 machos castrados com 19 a 20 meses de idade, divididos em oito grupos genéticos resultantes de cruzamentos Charolês x Nelore: 0, 25, 31, 38, 63, 69, 75 ou 100% Charolês. Os animais foram mantidos em confinamento e alimentados com uma dieta contendo 50% de volumoso e 50% de concentrado. O temperamento foi avaliado utilizando-se quatro metodologias adotadas durante as pesagens: escore composto (EC; tempo de saída (TS; distância de fuga (DF; e escore de localização do redemoinho de pêlos faciais (RED. Maiores porcentagens de sangue Charolês estiveram relacionadas positivamente ao ganho de peso diário. Independentemente do grupo genético, os animais mais reativos ganharam menos peso. O temperamento é influenciado pelo grupo genético, uma vez que animais com maiores proporções de sangue Nelore são mais agitados e excitáveis.The influence of the relation among genotype and temperament of cattle on the direct and indirect gains for meat production. Seventy-nine steers with 19-20 mo old from eight genotype groups of Charolais x Nellore crossbred were evaluated: CH (100CH, ¾ CH1/4N (0.75CH, 11/16CH5/16N (0.69CH, 5/8CH3/8N (0.63CH, 3/8CH5/8N (0.38CH, 5/16CH11/16N (0.31CH, 1/4CH3/4N (0.25CH e N (0CH animals were kept in feedlot and were fed with diet containing 50:50 forage to concentrate ratio (%DM. The temperament was evaluated using are four methods adopted during the cattle weights: composite behavior score (BC, flight time (FT; flight distance (FD, and facial whorl (W position score. Higher percentages of blood Charolais were positively related to daily weight gain. Regardless of the genetic group, the animals more reactive gained less daily weight gain. The temperament is influenced by genetic group, since animals with higher proportions of blood Nellore are more

  6. Seroreactivity of Salmonella-infected cattle herds against a fimbrial antigen in comparison with lipopolysaccharide antigens

    DEFF Research Database (Denmark)

    Hoorfar, Jeffrey; Lind, Peter; Bell, M.M.

    1996-01-01

    The IgG seroreaction of Salmonella-infected cattle herds against a fimbrial antigen (SEF14) was compared with that against lipopolysaccharide (LPS) antigens. Sera from 23 dairy herds (n = 205) from an island with no occurrence of salmonellosis, four herds (n = 303) with recent outbreaks of S...

  7. 9 CFR 78.9 - Cattle from herds not known to be affected.

    Science.gov (United States)

    2010-01-01

    ... 9 Animals and Animal Products 1 2010-01-01 2010-01-01 false Cattle from herds not known to be... BRUCELLOSIS Restrictions on Interstate Movement of Cattle Because of Brucellosis § 78.9 Cattle from herds not known to be affected. Male cattle which are not test eligible and are from herds not known to...

  8. Características de carcaça e da carne de novilhas Charolês e 3/4 Charolês 1/4 Nelore, terminadas em confinamento Carcass and meat characteristics of Charolais and 3/4 Charolais 1/4 Nellore cull heifers, finished in feedlot

    Directory of Open Access Journals (Sweden)

    João Restle

    2001-06-01

    Full Text Available O objetivo deste trabalho foi estudar os aspectos quantitativos e qualitativos da carcaça e da carne de novilhas de descarte dos genótipos Charolês (C e 3/4 C 1/4 Nelore (N. Foram usadas 25 novilhas de três anos, terminadas em confinamento por 80 dias. Não se verificou diferença para peso de abate (473,6 vs. 468,8 kg, peso de carcaça fria (241,8 vs. 241,8 kg, rendimento de carcaça fria (51,09 vs. 51,61%, espessura de gordura (4,13 vs. 4,78 mm, porcentagem de dianteiro (35,52 vs. 36,01% e de costilhar (15,03 vs. 15,42%, conformação (10,75 vs. 10,56 pontos e comprimento de carcaça (127,4 vs. 129,9 cm. As novilhas C apresentaram maior porcentagem do corte serrote (49,95 vs. 48,57% e perímetro de braço (36,73 vs. 35,00 cm que as ¾ C ¼ N. Não houve diferença significativa para a composição física da carcaça, cor (3,46 vs. 3,11 pontos, textura (3,67 vs. 3,33 pontos, marmoreio (6,40 vs. 5,00 pontos, maciez (6,48 vs. 6,19 pontos, palatabilidade (6,33 vs. 6,33 pontos e força para corte das fibras da carne, por meio do aparelho WB-Shear (5,99 vs. 6,24 pontos. A suculência da carne foi melhor nas novilhas C (6,18 vs. 5,67 pontos. A partir desses resultados, pode-se concluir que, para novilhas abatidas aos três anos, não existem diferenças expressivas nos aspectos quantitativos e qualitativos da carcaça e da carne entre os dois genótipos.The objective of this work was to study the quantitative and qualitative carcass and meat characteristics of Charolais (C and 3/4 C 1/4 Nellore (N cull heifers. Twenty-five culled heifers, three years old, were feedlot finished per 80 days period. No significant difference was observed for slaughter weight (473.6 vs. 468.8 kg, cold carcass weight (241.8 vs. 241.8 kg, dressing percentage (51.09 vs. 51.61%, fat thickness (4.13 vs. 4.78 mm, forequarter percentage (35.52 vs. 36.01%, sidecut percentage (15.03 vs. 15.42%, conformation (10.75 vs. 10.56 points and carcass length (127.4 vs. 129.9 cm. The

  9. Regional Eradication of Mycoplasma hyopneumoniae From Pig Herds and Documentation of Freedom of the Disease

    Directory of Open Access Journals (Sweden)

    Tuovinen V

    2001-09-01

    Full Text Available The objectives of this study were to 1 screen all sow herds in a region for M. hyopneumoniae, 2 to effectuate an eradication programme in all those herds which were shown to be infected with M. hyopneumoniae, and 3 to follow the success of the screening and the eradication programmes. The ultimate goal was to eradicate M. hyopneumoniae from all member herds of a cooperative slaughterhouse (153 farrowing herds + 85 farrowing-to-finishing herds + 150 specialised finishing herds before year 2000. During 1998 and 1999, a total of 5067 colostral whey and 755 serum samples (mean, 25 samples/herd were collected from sow herds and analysed for antibodies to M. hyopneumoniae by ELISA. Antibodies were detected in 208 (3.6% samples. Two farrowing herds (1.3% and 20 farrowing-to-finishing herds (23.5% were shown to be infected with M. hyopneumoniae. A programme to eradicate the infection from these herds was undertaken. During March 2000, a survey was made to prove the success of the screening and the eradication programmes. In total, 509 serum samples were collected randomly from slaughtered finishing pigs. Antibodies to M. hyopneumoniae were not detected in 506 of the samples, whereas 3 samples were considered suspicious or positive. Accordingly, 3 herds were shown to be infected. One of the herds was previously falsely classified as non-infected. Two of the herds were finishing herds practising continuous flow system (CF. Unlike finishing herds which practice all-in/all-out management routines on herd level, CF herds do not get rid of transmissible diseases spontaneously between batches, for which reason a screening was made in the rest of the CF herds (total n = 7. Consequently, 2 more infected herds were detected. In addition to the results of the survey, a decreasing prevalence of lung lesions at slaughter (from 5.2% to 0.1% and lack of clinical breakdowns indicated that all member herds were finally free from M. hyopneumoniae in the end of year 2000.

  10. Low prevalence of Salmonella in Swedish dairy herds highlight differences between serotypes.

    Science.gov (United States)

    Ågren, Estelle C C; Sternberg Lewerin, Susanna; Wahlström, Helene; Emanuelson, Ulf; Frössling, Jenny

    2016-03-01

    Legislated Salmonella control in Sweden has been in place since the 1960s. The purpose of this study was to investigate presence of Salmonella antibodies in dairy cattle herds and to provide a basis for decisions on how surveillance and control can be improved. Bulk milk samples from all Swedish dairy herds (n=4 683) were analysed with two different ELISAs; one detecting antibodies against Salmonella Dublin (Dublin ELISA), and one detecting antibodies against several of the serotypes causing bovine salmonellosis including S. Dublin (Bovine ELISA). Information about herds, i.e. geographical location, local animal density, number of test positive herds within 5km, animal trade and herd size, was based on register data. The results confirm a very low prevalence of Salmonella in Swedish dairy herds throughout the country with the exception of an island in the southeast. The test positive herds split into two groups; 41 herds (1%) positive in the Dublin ELISA, and 101 herds (2%) positive in the Bovine ELISA but negative in the Dublin ELISA. Geographical location of positive herds, and comparison of the results of the screening with serotypes previously isolated from some of the herds, indicated that the first group represents herds presently or previously infected with S. Dublin while the second group represents herds presently or previously infected with other serotypes. Differences in serological status between herds in different regions, of different size, with different animal purchase patterns et cetera, were tested using logistic regression. Presence of positive herds within 5km was significantly associated to testing positive. For herds testing positive in the Dublin ELISA, significant associations were also seen with herd size. Purchase of animals during the last year was not significantly associated with the outcome in the final models. We conclude that for future surveillance, the Bovine ELISA can be used to help in identifying infected herds, and the Dublin

  11. MERS Coronavirus in Dromedary Camel Herd Saudi Arabia

    OpenAIRE

    Hemida, Maged G.; Chu, Daniel K. W.; Poon, Leo L.M.; Perera, Ranawaka A. P. M.; Alhammadi, Mohammad A.; Ng, Hoi-yee; Siu, Lewis Y.; Guan, Yi; Alnaeem, Abdelmohsen; Peiris, Malik

    2014-01-01

    A prospective study of a dromedary camel herd during the 2013–14 calving season showed Middle East respiratory syndrome coronavirus infection of calves and adults. Virus was isolated from the nose and feces but more frequently from the nose. Preexisting neutralizing antibody did not appear to protect against infection.

  12. Genetic Analysis of the Henry Mountains Bison Herd.

    Directory of Open Access Journals (Sweden)

    Dustin H Ranglack

    Full Text Available Wild American plains bison (Bison bison populations virtually disappeared in the late 1800s, with some remnant animals retained in what would become Yellowstone National Park and on private ranches. Some of these private bison were intentionally crossbred with cattle for commercial purposes. This forced hybridization resulted in both mitochondrial and nuclear introgression of cattle genes into some of the extant bison genome. As the private populations grew, excess animals, along with their history of cattle genetics, provided founders for newly established public bison populations. Of the US public bison herds, only those in Yellowstone and Wind Cave National Parks (YNP and WCNP appear to be free of detectable levels of cattle introgression. However, a small free-ranging population (~350 animals exists on public land, along with domestic cattle, in the Henry Mountains (HM of southern Utah. This isolated bison herd originated from a founder group translocated from YNP in the 1940s. Using genetic samples from 129 individuals, we examined the genetic status of the HM population and found no evidence of mitochondrial or nuclear introgression of cattle genes. This new information confirms it is highly unlikely for free-living bison to crossbreed with cattle, and this disease-free HM bison herd is valuable for the long-term conservation of the species. This bison herd is a subpopulation of the YNP/WCNP/HM metapopulation, within which it can contribute significantly to national efforts to restore the American plains bison to more of its native range.

  13. Detection of a Novel Porcine Parvovirus in Chinese Swine Herds

    Science.gov (United States)

    To determine whether the recently reported novel porcine parvovirus type 4 (PPV4) is prevalent in China, a set of PPV4 specific primers were designed and used for the molecular survey of PPV4 among clinical samples. The results indicated a positive detection for PPV4 in Chinese swine herds of 1.84% ...

  14. Predation rate by wolves on the Porcupine caribou herd

    Directory of Open Access Journals (Sweden)

    Robert D. Hayes

    2000-04-01

    Full Text Available Large migratory catibou {Rangifer tarandus herds in the Arctic tend to be cyclic, and population trends are mainly driven by changes in forage or weather events, not by predation. We estimated daily kill rate by wolves on adult caribou in winter, then constructed a time and space dependent model to estimate annual wolf (Canis lupus predation rate (P annual on adult Porcupine caribou. Our model adjusts predation seasonally depending on caribou distribution: Pannual = SIGMAdaily* W *Ap(2*Dp. In our model we assumed that wolves killed adult caribou at a constant rate (Kdaily, 0.08 caribou wolf1 day1 based on our studies and elsewhere; that wolf density (W doubled to 6 wolves 1000 km2-1 on all seasonal ranges; and that the average area occupied by the Porcupine caribou herd (PCH in eight seasonal life cycle periods (Dp was two times gteater than the area described by the outer boundaries of telemetry data (Ap /1000 km2. Results from our model projected that wolves kill about 7600 adult caribou each year, regardless of herd size. The model estimated that wolves removed 5.8 to 7.4% of adult caribou as the herd declined in the 1990s. Our predation rate model supports the hypothesis of Bergerud that spacing away by caribou is an effective anti-predatory strategy that greatly reduces wolf predation on adult caribou in the spring and summer.

  15. Copper deficiency in a herd of captive muskoxen.

    OpenAIRE

    Blakley, B R; S. C. Tedesco; Flood, P F

    1998-01-01

    At necropsy, a mature muskox cow was found to have exceedingly low serum and liver copper concentrations of 4.8 = mumol/L and 0.02 mmol/kg, respectively. Serum copper levels were also low in remaining members of the herd but returned to normal after parenteral treatment with calcium copper edetate.

  16. Prevalence of Coxielle Burnetii anbitodies in Danish Dairy herds

    DEFF Research Database (Denmark)

    Agger, Jens F.; Christoffersen, Anna-Bodil; Rattenborg, Erik

    2010-01-01

    During recent years in Denmark higher rates of antibodies to Coxiella burnetii have been detected in animals and humans than previously reported. A study based on bulk tank milk samples from 100 randomly selected dairy herds was performed to estimate the prevalence and geographical distribution o...

  17. Study of linearity of LYSO crystal for HERD calorimeter

    CERN Document Server

    Quan, Zheng; Xu, Ming; Dong, Yong-wei; Wang, Jun-jing; An, Guang-peng; Liu, Xin; Bao, Tian-wei; Zhang, Li; Wang, Rui-jie; Lv, Jun-guang; Wu, Bo-bing; Zhang, Shuang-nan

    2016-01-01

    The High Energy cosmic Radiation Detection (HERD) facility is one of the space astronomy payloads of the cosmic light house program onboard the China's Space Station. HERD is designed for detecting electrons and $\\gamma$-rays up to tens of TeV and cosmic rays up to several PeV. The main instrument of HERD is a 3-D imaging calorimeter (CALO) composed of nearly ten thousand cubic LYSO crystals. Each crystal coupled with spiral Wavelength Shifting Fibers (WLSF) is defined as a HERD CALO Cell (HCC). The required energy range of one HCC is from 10 MeV to 50 TeV. In order to verify the linearity of HCC in such a wide energy range, a beam test has been implemented at the E2 and E3 beam lines of BEPCII. The setup of the beam test and linearity performance are reviewed in this paper. The study shows the linearity of HCC is better than 10\\% in the required energy range.

  18. Grass tetany in a herd of beef cows.

    Science.gov (United States)

    Odette, O

    2005-08-01

    Five cows in a herd of 15 cattle that had just been turned out onto lush pasture after having over-wintered on poor quality hay died suddenly. Biochemical profiles collected from the cadavers revealed reduced serum levels of magnesium, urea, and beta-hydroxybutycate. Classical grass tetany (hypomagnesemia) was diagnosed on postmortem examination.

  19. Impact if hyperprolific line of litter size in multiplication herd

    Directory of Open Access Journals (Sweden)

    Zdeněk Tvrdoň

    2009-01-01

    Full Text Available The hyperprolific line is considered to be maximally effective in pursuit of progress in sow’s reproduction. Hyperprolific line efficiency is commonly evaluated in regard of breeding herd progress. We decided to study how effective it is with respect to increasing of litter size in multiplication herd. Our study is specific by using the data from practice, concretely it is based on the information about the ancestor of sows in multiplication herd. The ancestors could be the member either hyperprolific line or normal line. The information about performances of sows breed in multiplication herd was known. The mixed linear models in SAS for Windows 9.1.2. were conducted to statistical analysis. Our results indicated that no significant effect on litter size was achieved by selection criteria used in the hyperprolific line creation. In studied population no differences between TNB, NBA or NW were found on the 1st as well as on the 1st–5th litters. As we have mentioned above, the study is specific by using the data from practice. Therefore the studied population size is limited. It is necessary to take into consideration when the results are applied. Nevertheless, the results shown that other studies with larger population should be done to reevaluate the selection criteria.

  20. Financial aspects of veterinary herd health management programmes

    NARCIS (Netherlands)

    Ifende, V.I.; Derks, M.; Hooijer, G.A.; Hogeveen, H.

    2014-01-01

    Veterinary herd health management (VHHM) programmes have been shown to be economically effective in the past. However, no current information is available on costs and benefits of these programmes. This study compared economics and farm performance between participants and non-participants in VHHM p

  1. A genetic study of loser cows in Danish dairy herds

    DEFF Research Database (Denmark)

    Pedersen, Louise Dybdahl; Jørgensen, Hanne Birgitte Hede; Kargo, Morten

    2013-01-01

    Following the recent years' increase in herd size, the awareness of a group of cows with a generally lowered health and production level, the “loser cows,” has arisen in Denmark. The aim of this study was to estimate genetic correlations between the loser cow score, 305d protein yield and realize...

  2. Mexican agencies reach teenagers.

    Science.gov (United States)

    Brito Lemus, R; Beamish, J

    1992-08-01

    The Gente Joven project of the Mexican Foundation for Family Planning (MEXFAM) trains young volunteers in 19 cities to spread messages about sexually transmitted diseases and population growth to their peers. They also distribute condoms and spermicides. It also uses films and materials to spread its messages. The project would like to influence young men's behavior, but the Latin image of machismo poses a big challenge. It would like to become more responsible toward pregnancy prevention. About 50% of adolescents have sexual intercourse, but few use contraceptives resulting in a high adolescent pregnancy rate. Many of these pregnant teenagers choose not to marry. Adolescent pregnancy leads to girls leaving school, few marketable skills, and rearing children alone. Besides women who began childbearing as a teenager have 1.5 times more children than other women. Male involvement in pregnancy prevention should improve these statistics. As late as 1973, the Health Code banned promotion and sales of contraceptives, but by 1992 about 50% of women of reproductive age use contraceptives. The Center for the Orientation of Adolescents has organized 8 Young Men's Clubs in Mexico City to involve male teenagers more in family planning and to develop self-confidence. It uses a holistic approach to their development through discussions with their peers. A MEXFAM study shows that young men are not close with their fathers who tend to exude a machismo attitude, thus the young men do not have a role model for responsible sexual behavior. MEXFAM's work is cut out for them, however, since the same study indicates that 50% of the young men believe it is fine to have 1 girlfriend and 33% think women should earn more than men. A teenager volunteer reports, however, that more boys have been coming to him for contraception and information than girls in 1992 while in other years girls outnumbered the boys.

  3. AIDS in Mexican prisons.

    Science.gov (United States)

    Olivero, J M; Roberts, J B

    1995-01-01

    The human rights organization Americas Watch, which toured Mexican prisons, reported in 1991 that all prisoners with HIV infection in the Mexico City area were housed in a single AIDS ward in Santa Marta Prison. In 1991, the 16-bed facility had 15 patients; in 1993, this number had increased by 5. In Mexico City, with 3 prisons holding over 2000 male adults each, there were only 20 known infected prisoners in the AIDS ward at Santa Marta. In 1991, authorities at Matamoros, in the state of Tamaulipas, insisted that none of their inmates had ever been diagnosed as infected with HIV. The prison physician at Reynosa indicated that only 2 inmates since 1985 had ever been diagnosed as infected. In 1992, the prison in Saltillo, in the state of Coahuila, reported that here had yet to be a single positive test for HIV. The prison at Reynosa held 1500 people and only 2 inmates were diagnosed as having AIDS between 1985 and 1991. Prisons at Matamoros and Saltillo held similar numbers but had no experience of infected inmates. A survey of 2 prisons in the state of Tamaulipas indicates that around 12% of the population may use IV drugs, and 9% indicate sharing needles. It is possible for prisoners to die of diseases like pneumonia, associated with AIDS, without the connection to AIDS being diagnosed. Each state, and possibly each prison in Mexico, has its own particular AIDS policies. Santa Marta was the single facility in Mexico City used to house AIDS-infected prisoners, who were segregated. Finally, the prison at Saltillo required all women entering the facility to have a medical examination, including a test for HIV. High-level prison personnel have demonstrated ignorance and fear of AIDS and intolerance of infected prisoners. Mexico must reassess the need to provide adequate medical care to offenders who are sick and dying behind bars.

  4. Random within-herd variation in financial performance and time to financial steady-state following management changes in dairy herd

    DEFF Research Database (Denmark)

    Kristensen, Erling Lundager; Østergaard, Søren; Krogh, Mogens Agerbo

    2008-01-01

    The manager of a dairy herd and the affiliated consultants constantly need to judge whether financial performance of the production system is satisfactory and whether financial performance relates to real (systematic) effects of changes in management. This is no easy task because the dairy herd...... is a very complex system. Thus, it is difficult to obtain empirical data that allows a valid estimation of the random (within-herd) variation in financial performance corrected for management changes. Thus, simulation seems to be the only option. This study suggests that much caution must be recommended...... when claming effect of changes in herd management because the link between management changes (cause) and effect (measured as improvement of gross margin per cow year) is extensively blurred by a large within-herd variation in available real life accounting data and differences between herds in time...

  5. The Impacts of Emigration on the Mexican Economy.

    Science.gov (United States)

    Newman, Allen R.

    1982-01-01

    The assumption that Mexican emigration to the United States provides benefits to Mexico in the form of jobs for unemployed Mexicans and wage remittances has kept Mexican officials from discouraging illegal emigration. In fact, emigration drains the Mexican economy and should be a cause for Mexican government concern. (Author/MJL)

  6. A simulation model to quantify the value of implementing whole-herd Bovine viral diarrhea virus testing strategies in beef cow-calf herds.

    Science.gov (United States)

    Nickell, Jason S; White, Brad J; Larson, Robert L; Renter, David G; Sanderson, Mike W

    2011-03-01

    Although numerous diagnostic tests are available to identify cattle persistently infected (PI) with Bovine viral diarrhea virus (BVDV) in cow-calf herds, data are sparse when evaluating the economic viability of individual tests or diagnostic strategies. Multiple factors influence BVDV testing in determining if testing should be performed and which strategy to use. A stochastic model was constructed to estimate the value of implementing various whole-herd BVDV cow-calf testing protocols. Three common BVDV tests (immunohistochemistry, antigen-capture enzyme-linked immunosorbent assay, and polymerase chain reaction) performed on skin tissue were evaluated as single- or two-test strategies. The estimated testing value was calculated for each strategy at 3 herd sizes that reflect typical farm sizes in the United States (50, 100, and 500 cows) and 3 probabilities of BVDV-positive herd status (0.077, 0.19, 0.47) based upon the literature. The economic value of testing was the difference in estimated gross revenue between simulated cow-calf herds that either did or did not apply the specific testing strategy. Beneficial economic outcomes were more frequently observed when the probability of a herd being BVDV positive was 0.47. Although the relative value ranking of many testing strategies varied by each scenario, the two-test strategy composed of immunohistochemistry had the highest estimated value in all but one herd size-herd prevalence permutation. These data indicate that the estimated value of applying BVDV whole-herd testing strategies is influenced by the selected strategy, herd size, and the probability of herd BVDV-positive status; therefore, these factors should be considered when designing optimum testing strategies for cow-calf herds.

  7. An object-oriented Bayesian network modeling the causes of leg disorders in finisher herds

    DEFF Research Database (Denmark)

    Jensen, Tina Birk; Kristensen, Anders Ringgaard; Toft, Nils

    2009-01-01

    The implementation of an effective control strategy against disease in a finisher herd requires knowledge regarding the disease level in the herd. A Bayesian network was constructed that can estimate risk indexes for three cause-categories of leg disorders in a finisher herd. The cause...... pigs (e.g. results from diagnostic tests) were used to estimate the most likely cause of leg disorders at herd level. As information to the model originated from two different levels, we used an object-oriented structure in order to ease the specification of the Bayesian network. Hence, a Herd class...

  8. Is There Herd Effect on Stocks with High Liquidity of the Brazilian Market?

    Directory of Open Access Journals (Sweden)

    Juliana Xavier Serapio da Silva

    2015-08-01

    Full Text Available Purpose: This work aims to verify the herd behavior in both liquid stocks of Brazilian stock exchange, i.e. Petrobras and Vale.Methodology: This work uses the methods of Christie and Huang (1995 and price pressure with high frequency data to detect the herd behavior between 2010 and 2014.Findings: The first method suggest that there are no signs of herd behavior using 30 minutes intervals data. However, there is evidence of price pressure for the sample with all intraday data.Originality: Herd behavior studies usually focus on mutual funds. This work analyses the herd behavior based on individual stock prices. 

  9. New evidence of anti-herding of oil-price forecasters

    Energy Technology Data Exchange (ETDEWEB)

    Pierdzioch, Christian [Universitaet des Saarlandes, Rechts- und Wirtschaftswissenschaftliche Fakultaet, Postfach 15 11 50, 66041 Saarbruecken (Germany); Ruelke, Jan Christoph [Department of Economics, WHU, Otto Beisheim School of Management, Burgplatz 2, 56179 Vallendar (Germany); Stadtmann, Georg [University of Southern Denmark (SDU), Department of Business and Economics, Campusvej 55, 5230 Odense M (Denmark); Europa-Universitaet Viadrina, Fakultaet fuer Wirtschaftswissenschaften, Postfach 1786, 15207 Frankfurt (Oder) (Germany)

    2010-11-15

    We used the oil-price forecasts of the Survey of Professional Forecasters published by the European Central Bank to analyze whether oil-price forecasters herd or anti-herd. Oil-price forecasts are consistent with herding (anti-herding) of forecasters if forecasts are biased towards (away from) the consensus forecast. Based on a new empirical test developed by Bernhardt et al. (J. Financ. Econ. 80: 657-675, 2006), we found strong evidence of anti-herding among oil-price forecasters. (author)

  10. Spread of Staphylococcus aureus resistant to penicillin and tetracycline within and between dairy herds

    DEFF Research Database (Denmark)

    Waage, S.; Bjorland, J.; Caugant, D. A.

    2002-01-01

    One hundred and seven bovine isolates of penicillin and tetracycline resistant Staphylococcus aureus, recovered from 25 different dairy herds in various parts of Norway, were characterized using antimicrobial susceptibility testing, multilocus enzyme electrophoresis, ribotyping, plasmid analysis...... and serotyping of capsular polysaccharide. Forty-one isolates from one particular herd, 37 isolates from 5 herds that used a common pasture and milking parlour in summer and 21 isolates from 12 herds in 8 different counties belonged to the same strain. The remaining 8 isolates, which originated from herds in 5...

  11. Induction of porcine post-weaning multisystemic wasting syndrome (PMWS) in pigs from PMWS unaffected herds following mingling with pigs from PMWS-affected herds

    DEFF Research Database (Denmark)

    Kristensen, Charlotte Sonne; Bækbo, Poul; Bille-Hansen, Vivi;

    2009-01-01

    In this paper we present the results from two experimental studies (I and II) investigating whether post-weaning multisystemic wasting syndrome (PMWS) can be induced in pigs from PMWS unaffected herds by mingling with pigs from PMWS-affected herds and to observe whether transportation and...... compartments in both study I and study II. In addition, in study II, four groups of pigs from unaffected herds were included. Two groups with pigs transported and mingled from unaffected herds and two groups with pigs which were only transported. The PMWS diagnoses on the individual pigs were based on lymphoid...

  12. Mexican High Energy Physics Network

    Science.gov (United States)

    D'Olivo, J. C.; Napsuciale, M.; Pérez-Angón, M. A.

    2016-10-01

    The Mexican High Energy Physics Network is one of CONACYT's thematic research networks, created with the aim of increasing the communication and cooperation of the scientific and technology communities of Mexico in strategic areas. In this report we review the evolution, challenges, achievements and opportunities faced by the network.

  13. The Mexican Axolotl in Schools

    Science.gov (United States)

    Thomas, R. M.

    1976-01-01

    Suggests and describes laboratory activities in which the Mexican axolotl (Ambystoma mexicanum Shaw) is used, including experiments in embryology and early development, growth and regeneration, neoteny and metamorphosis, genetics and coloration, anatomy and physiology, and behavior. Discusses care and maintenance of animals. (CS)

  14. Historical aspects of Mexican psychiatry.

    Science.gov (United States)

    Bayardo, Sergio Javier Villaseñor

    2016-04-01

    Mexican psychiatry initiated since pre-Hispanic times. Historically, treatments were a mixture of magic, science and religion. Ancient Nahuas had their own medical concepts with a holistic view of medicine, considering men and cosmos as a whole. The first psychiatric hospital appeared in 1566 and a more modern psychiatric asylum emerged until 1910. International exchanges of theoretical approaches started in the National University with the visit of Pierre Janet. There were other important figures that influenced Mexican psychiatry, such as Erich Fromm, Henri Ey, Jean Garrabé and Yves Thoret. Regarding Mexican psychiatrists, some of the most important contributors to Mexican psychiatry were José Luis Patiño Rojas, Manuel Guevara Oropeza and Ramón de la Fuente Muñiz. This article includes excerpts from "Clinical Psychiatry", a book by Patiño Rojas where he tries to understand and describe the inner world experienced by patients with schizophrenia; also, the thesis conducted by Guevara Oropeza ("Psychoanalisis"), which is a critical comparison between the theories of Janet and Freud. Finally, we include "The study of consciousness: current status" by Ramón de la Fuente, which leads us through the initial investigations concerning consciousness, its evolution, and the contributions made by psychology, philosophy and neurobiology.

  15. The Mexican Axolotl in Schools

    Science.gov (United States)

    Thomas, R. M.

    1976-01-01

    Suggests and describes laboratory activities in which the Mexican axolotl (Ambystoma mexicanum Shaw) is used, including experiments in embryology and early development, growth and regeneration, neoteny and metamorphosis, genetics and coloration, anatomy and physiology, and behavior. Discusses care and maintenance of animals. (CS)

  16. La Artesania Mexicana (Mexican Handicrafts).

    Science.gov (United States)

    Steele, Bettina

    This booklet contains instructions in English and Spanish for making eleven typical Mexican craft articles. The instructions are accompanied by pen-and-ink drawings. The objects are (1) "La Rosa" (The Rose); (2) "El Crisantemo" (The Chrysanthemum); (3) "La Amapola" (The Poppy); (4) "Ojos de Dios" (God's Eyes); (5) "Ojitos con dos caras" (Two-Sided…

  17. Pedagogics in Mexican American Studies.

    Science.gov (United States)

    Carranza, E. Lou

    A pedagogy appropriate to college level courses and comprised of interdisciplinary content, multidisciplinary faculty, and students from diverse academic backgrounds and with varying levels of skills merits development. A taxonomy of some of the difficulties in the construction of such a course in Mexican American studies, for example, focuses on…

  18. Pedagogics in Mexican American Studies.

    Science.gov (United States)

    Carranza, E. Lou

    A pedagogy appropriate to college level courses and comprised of interdisciplinary content, multidisciplinary faculty, and students from diverse academic backgrounds and with varying levels of skills merits development. A taxonomy of some of the difficulties in the construction of such a course in Mexican American studies, for example, focuses on…

  19. A European longitudinal study in Salmonella seronegative and seropositive-classified finishing pig herds

    DEFF Research Database (Denmark)

    Wong, Danilo Lo Fo; Dahl, J.; Wingstrand, Anne;

    2004-01-01

    in pig herds. For this purpose, 17 finishing pig herds initially classified as seropositive and 15 as seronegative, were followed for a 2-year period through serological and bacteriological sampling. The study included 10 herds from Denmark, 13 from The Netherlands, 4 from Germany and 5 from Sweden...... and was performed between October 1996 and May 1999. The Salmonella status of finishing pig herds was determined by an initial blood sampling of approximately 50 finishing pigs close to market weight per herd. The development of the Salmonella status of the selected herds was assessed at seven subsequent sampling.......0, 95 % CI 3.2-32.8). When Salmonella was isolated from pen faecal samples, the herd was more likely to be classified seropositive in the same sampling round, compared to no Salmonella being detected (OR 4.0, 95 % CI 1.1-14.6). The stability of an initially allocated Salmonella status was found to vary...

  20. The effect of cephalosporin usage on the occurrence of ESCs producing E. coli in pig herds

    DEFF Research Database (Denmark)

    Dalhoff Andersen, Vibe; Jensen, Vibeke Frøkjær; Agersø, Yvonne

    in 19 pig herds which have had five to fourteen prescriptions of ceph. and 20 pig herds without prescribed ceph. in a previous 12 month period. The 39 herds were all integrated and represent typical Danish pig farms. The occurrence of ESCs producing E. coli in the herds were tested in a total of 9...... pooled samples per herd. A pig herd was considered positive if one or more of the nine samples contained ESCs producing E. coli. Initially, the association between usages of ceph. and occurrence of ESCs producing E. coli in the pig herds was analyzed using logistic regression, and the effect was adjusted...... of ESCs producing E. coli was estimated as risk ratio(RR). The results showed that consumption of ceph. increased the risk of occurrence of ESCs producing E. coli significantly with a RR of 5 (95% CI: 2-11). This demonstrates that ceph. usage significant affect the occurrence of ESCs resistance...

  1. HERDING BEHAVIOR UNDER MARKETS CONDITION: EMPIRICAL EVIDENCE ON THE EUROPEAN FINANCIAL MARKETS

    Directory of Open Access Journals (Sweden)

    Moatemri Ouarda

    2013-01-01

    Full Text Available This study presents four main contributions to the literature of behavior herding. Firstly, it extends the behavioral researches of herding of the investors on a developed market and mainly on a European market as a whole. Secondly, we are interested in examination of herding behavior at the level of sectors by using data at the levels of companies. Thirdly, this document estimates the implications of herding behavior in terms of returns, volatility and volume of transaction. Fourthly, the herding behavior is revealed as well during the period of the recent global financial crisis in 2007-2008 and of Asian crisis. Our results reveal a strong evidence of herding behavior sharply contributed to a bearish situation characterized by a strong volatility and a trading volume. The repercussion of herding during the period of the recent financial crisis is clearly revealed for the sectors of the finance and the technology.

  2. The effect of cephalosporin usage on the occurrence of ESCs producing E. coli in pig herds

    DEFF Research Database (Denmark)

    Dalhoff Andersen, Vibe; Jensen, Vibeke Frøkjær; Agersø, Yvonne

    in 19 pig herds which have had five to fourteen prescriptions of ceph. and 20 pig herds without prescribed ceph. in a previous 12 month period. The 39 herds were all integrated and represent typical Danish pig farms. The occurrence of ESCs producing E. coli in the herds were tested in a total of 9...... pooled samples per herd. A pig herd was considered positive if one or more of the nine samples contained ESCs producing E. coli. Initially, the association between usages of ceph. and occurrence of ESCs producing E. coli in the pig herds was analyzed using logistic regression, and the effect was adjusted...... of ESCs producing E. coli was estimated as risk ratio(RR). The results showed that consumption of ceph. increased the risk of occurrence of ESCs producing E. coli significantly with a RR of 5 (95% CI: 2-11). This demonstrates that ceph. usage significant affect the occurrence of ESCs resistance...

  3. The importance of 'neighbourhood' in the persistence of bovine tuberculosis in Irish cattle herds.

    Science.gov (United States)

    White, Paul W; Martin, S Wayne; De Jong, Mart C M; O'Keeffe, James J; More, Simon J; Frankena, Klaas

    2013-07-01

    Local persistence of infection is a key feature of bovine tuberculosis (bTB) among cattle herds in the Republic of Ireland. The aim of this study was to determine the relative importance of 'neighbourhood', specifically farm-to-farm spread and spread from wildlife, in the persistence of bTB by investigating herds having a bTB episode in 2006. A case-control study was conducted on the association between the occurrence of a bTB episode in 2006 and the occurrence of bTB in previous years among neighbouring herd(s) within 1 km, while controlling for each herd's bTB history and other risk factors. Neighbouring herds were grouped into three zones, based on distance, and bTB incidence measures summarised within each zone and by calendar year (2001-2005). The incidence of bTB was associated with an increased animal incidence in two subsets of neighbouring herds: (i) herds directly contiguous during the previous 2 years (attributable fraction=0.20), and (ii) herds at a distance of >25 m in the previous year (attributable fraction=0.19). Other predictors of bTB in a herd in 2006 included the occurrence of a bTB episode within that herd in any of the previous 5 years, herd size, and the number of animals purchased at age greater than 12 months. An infected wildlife source best explains the existence of a "neighbouring herd risk" for bTB at distances greater than 25 m. Further studies will be necessary to determine to what extent neighbouring herd risk within 25 m may be confounded by the same wildlife (badger) source.

  4. ENZYME-LINKED-IMMUNOSORBENT-ASSAY FOR SCREENING OF MILK SAMPLES FOR SALMONELLA-TYPHIMURIUM IN DAIRY HERDS

    DEFF Research Database (Denmark)

    Hoorfar, Jeffrey; Wedderkopp, A.

    1995-01-01

    positive (herd specificity, 0.9 and herd sensitivity, 1.0). A sig nificant correlation (P serum and milk samples from cows in the herds with a history of salmonellosis. It was concluded that ELISA testing of individual milk sam ples can be used for surveillance......We investigated the ability of an antibody-specific, O antigen-based ELISA to document Salmonella typhimurium herd infections by screening of milk samples. Three cattle populations, 20 herds with no history of salmonellosis, 8 herds with history of S typhimurium epsiodes within the previous 7...... of herds for S typhimurium infections, but further modifications are needed to test bulk tank milk samples....

  5. Modelling Pasture-based Automatic Milking System Herds: The Impact of Large Herd on Milk Yield and Economics

    Directory of Open Access Journals (Sweden)

    M. R. Islam

    2015-07-01

    Full Text Available The aim of this modelling study was to investigate the effect of large herd size (and land areas on walking distances and milking interval (MI, and their impact on milk yield and economic penalties when 50% of the total diets were provided from home grown feed either as pasture or grazeable complementary forage rotation (CFR in an automatic milking system (AMS. Twelve scenarios consisting of 3 AMS herds (400, 600, 800 cows, 2 levels of pasture utilisation (current AMS utilisation of 15.0 t dry matter [DM]/ha, termed as ‘moderate’; optimum pasture utilisation of 19.7 t DM/ha, termed as ‘high’ and 2 rates of incorporation of grazeable complementary forage system (CFS: 0, 30%; CFS = 65% farm is CFR and 35% of farm is pasture were investigated. Walking distances, energy loss due to walking, MI, reduction in milk yield and income loss were calculated for each treatment based on information available in the literature. With moderate pasture utilisation and 0% CFR, increasing the herd size from 400 to 800 cows resulted in an increase in total walking distances between the parlour and the paddock from 3.5 to 6.3 km. Consequently, MI increased from 15.2 to 16.4 h with increased herd size from 400 to 800 cows. High pasture utilisation (allowing for an increased stocking density reduced the total walking distances up to 1 km, thus reduced the MI by up to 0.5 h compared to the moderate pasture, 800 cow herd combination. The high pasture utilisation combined with 30% of the farm in CFR in the farm reduced the total walking distances by up to 1.7 km and MI by up to 0.8 h compared to the moderate pasture and 800 cow herd combination. For moderate pasture utilisation, increasing the herd size from 400 to 800 cows resulted in more dramatic milk yield penalty as yield increasing from c.f. 2.6 and 5.1 kg/cow/d respectively, which incurred a loss of up to $AU 1.9/cow/d. Milk yield losses of 0.61 kg and 0.25 kg for every km increase in total walking distance

  6. Mexican Perspectives on Mexican-U.S. Relations

    Science.gov (United States)

    1993-04-01

    administration of Mexican President Porfirio Diaz (1876 - 1911). He was a dictator whose pervasive and ruthless administration is considered an...placing the agricultural system in the hands of a few wealthy landowners. Porfirio Diaz accomplished his objectives by establishing an oligarchy...violent coup staged by Generals Victoriano Huerta and Felix Diax that overthrew the government of Porfirio Diaz ’ successor, President Francisco Madero

  7. Wolf predation in the Burwash caribou herd, southwest Yukon

    Directory of Open Access Journals (Sweden)

    David A. Gauthier

    1986-06-01

    Full Text Available The role of wolf predation as a proximate mortality factor influencing caribou herd growth was assessed in the Burwash herd (400 animals in the southwest Yukon between 1980 - 1982. Ten to 14 wolves in two packs preyed primarily on caribou (Rangifer tarandus caribou and moose (Alces alces with disproportionate consumption of caribou (relative to available biomass in the rut and winter periods. Wolf predation was responsible for 72% of total annual mortality in 1980 - 1981 and 46% in 1981 - 1982. Losses due to human harvest varied between 7 to 13%. Additional limited data on climatic factors and winter forage indicated forage-climate were not major proximate mortality factors in 1980 - 1981, but that early-calving climate may have been a factor in increased calf mortality in 1982.

  8. Herd Clustering: A synergistic data clustering approach using collective intelligence

    KAUST Repository

    Wong, Kachun

    2014-10-01

    Traditional data mining methods emphasize on analytical abilities to decipher data, assuming that data are static during a mining process. We challenge this assumption, arguing that we can improve the analysis by vitalizing data. In this paper, this principle is used to develop a new clustering algorithm. Inspired by herd behavior, the clustering method is a synergistic approach using collective intelligence called Herd Clustering (HC). The novel part is laid in its first stage where data instances are represented by moving particles. Particles attract each other locally and form clusters by themselves as shown in the case studies reported. To demonstrate its effectiveness, the performance of HC is compared to other state-of-the art clustering methods on more than thirty datasets using four performance metrics. An application for DNA motif discovery is also conducted. The results support the effectiveness of HC and thus the underlying philosophy. © 2014 Elsevier B.V.

  9. Technical indicators of financial performance in the dairy herd

    DEFF Research Database (Denmark)

    Kristensen, Erling Lundager; Østergaard, Søren; Krogh, Mogens Agerbo

    2008-01-01

    Monte Carlo simulation was used to predict the long-term financial performance related to the technical performance of dairy herds. The indicators addressed were derived from data collected routinely in the herd. They indicated technical performance that can be affected by the farmer......, mortality in cows and calves, dynamics of body condition, and somatic cell counts. Each indicator was defined by 2 or 3 levels, and 2- and 3-factor interactions were included in the simulation experiment, which included 72 scenarios. Each scenario was replicated 200 times, and the resulting gross margin per...... increased the gross margin 2.6 times more than improved reproduction efficiency, which again increased the gross margin 2.6 to 5.9 times more than improved management related to heifers, body condition score, mortality, and somatic cell counts. These results were implemented in a simple "metamodel...

  10. Follow the Leader: Herding Behavior in Heterogeneous Populations

    CERN Document Server

    Mosquera-Donate, Guillem

    2014-01-01

    Here we study the emergence of spontaneous leadership in large populations. In standard models of opinion dynamics, herding behavior is only obeyed at the local scale due to the interaction of single agents with their neighbors; while at the global scale, such models are governed by purely diffusive processes. Surprisingly, in this paper we show that the combination of a strong separation of time scales within the population and a hierarchical organization of the influences of some agents on the others induces a phase transition between a purely diffusive phase, as in the standard case, and a herding phase where a fraction of the agents self-organize and lead the global opinion of the whole population.

  11. Herd composition and slaughtering strategy in reindeer husbandry – revisited

    Directory of Open Access Journals (Sweden)

    Øystein Holand

    2007-04-01

    Full Text Available I will review the drastic change seen in herd composition and slaughtering strategy the last decades inthe reindeer husbandry of Fennoscandia (i. e. Finland, Norway and Sweden. Herd composition was traditionally a function of the multipurpose herd, where reproduction of draught power played a major role. Hence, the slaughter scheme was based on adult males, in particular castrates. The herd represented the owner's capital and was viewed as the best insurance for staying in business. Indeed, a big and well composed herd announced social status as well as authority. Historically this has resulted in rises and falls in reindeer numbers. Control of the herd was being emphasized through age and sex composition and selection of behavioural traits and easily recognisable animals which favour handling. A high proportion of adults alleviated control of the herd as it eased the herding and reduced the mortality risk as they were able to withstand the highly stochastic environment. The introduction of the snowmobiles in the 1960s revolutionized the herding and transportation and hence reduced the importance of the male segment of the herd and amplified the ongoing transformation of the modern society into a market based economy. Now, the challenge was to efficiently convert the limited primary plant production into animal product, mainly meat. This is primarily achieved by balancing the animal numbers in accordance to the forage resources. However, also herd composition and slaughtering strategy are essential for maximizing the meat output per area unit. A highest possible proportion of reproductive females combined with a slaughtering scheme based on calves was tested and partly implemented in Soviet-Union already in the 1930s and introduced in the 1960s in Finland. Also in parts of Norway and Sweden this scheme was modified and tested. However, the formal work of refining and testing this new strategy based on modern population theory blended with

  12. Mastitis and related management factors in certified organic dairy herds in Sweden

    Directory of Open Access Journals (Sweden)

    Hansson Ingrid

    2006-07-01

    Full Text Available Abstract Background Mastitis is one of the major threats to animal health, in organic farming as well as conventional. Preliminary studies of organic dairy herds have indicated better udder health in such herds, as compared to conventional herds. The aim of this paper was to further study mastitis and management related factors in certified organic dairy herds. Methods An observational study of 26 certified organic dairy herds in mid-eastern Sweden was conducted during one year. A large-animal practitioner visited the herds three times and clinically examined and sampled cows, and collected information about general health and management routines. Data on milk production and disorders treated by a veterinarian in the 26 herds, as well as in 1102 conventional herds, were retrieved from official records. Multivariable logistic regression was used to assess associations between herd type (organic vs. conventional and incidence of disorders. Results The organic herds that took part in the study ranged in size from 12 to 64 cows, in milk production from 3772 to 10334 kg per cow and year, and in bulk milk somatic cell counts from 83000 to 280000 cells/ml. The organic herds were found to have a lower incidence of clinical mastitis, teat injuries, and a lower proportion of cows with a high somatic cell count (as indicated by the UDS, Udder Disease Score compared to conventional herds. The spectrum of udder pathogenic bacteria was similar to that found in other Swedish studies. Treatment of mastitis was found to be similar to what is practised in conventional herds. Homeopathic remedies were not widely used in the treatment of clinical mastitis. The calves in most of these organic herds suckled their dams for only a few days, which were not considered to substantially affect the udder health. The main management factor that was different from conventional herds was the feeding strategy, where organic herds used a larger share of forage. Conclusion Udder

  13. Rotavirus vaccination and herd immunity: an evidence-based review

    Directory of Open Access Journals (Sweden)

    Seybolt LM

    2012-06-01

    Full Text Available Lorna M Seybolt, Rodolfo E BéguéDepartment of Pediatrics, Division of Infectious Diseases, Louisiana State University Health Sciences Center, New Orleans, LA, USAAbstract: Until recently, rotavirus was the most common cause of diarrhea in infants and young children with over 100 million cases and 400,000 deaths every year worldwide. Yet, its epidemiology is changing rapidly with the introduction of two rotavirus vaccines in the mid 2000s. Both vaccines were shown to be highly efficacious in prelicensure studies to reduce severe rotavirus disease; the efficacy being more pronounced in high- and middle-income countries than in low-income countries. Herd immunity – the indirect protection of unimmunized individuals as a result of others being immunized – was not expected to be a benefit of rotavirus vaccination programs since the vaccines were thought to reduce severe disease but not to decrease virus transmission significantly. Postlicensure studies, however, have suggested that this assumption may need reassessment. Studies in a variety of settings have shown evidence of greater than expected declines in rotavirus disease. While these studies were not designed specifically to detect herd immunity – and few failed to detect this phenomenon – the consistency of the evidence is compelling. These studies are reviewed and described here. While further work is needed, clarifying the presence of herd immunity is not just an academic exercise but an important issue for rotavirus control, especially in lower income countries where the incidence of the disease is highest and the direct protection of the vaccines is lower.Keywords: rotavirus, vaccine, herd immunity, efficacy

  14. Rational herd behavior and the globalization of securities markets

    OpenAIRE

    Guillermo A. Calvo; Enrique G. Mendoza

    1997-01-01

    This paper shows that globalization of securities markets exacerbates the volatility of capital flows by strengthening incentives for herding behavior. This is a prediction of a mean-variance portfolio optimization model with imperfect information, in which investors acquire country-specific expertise at a fixed cost and incur variable reputational costs. The model produces equilibria in which incentives to confirm rumors decrease with globalization. Simulations based on equity markets data a...

  15. Pedigree and herd characterization of a donkey breed vulnerable to extinction.

    Science.gov (United States)

    Quaresma, M; Martins, A M F; Rodrigues, J B; Colaço, J; Payan-Carreira, R

    2014-03-01

    Most donkey and local horse breeds are vulnerable to extinction as mechanization of agriculture progress throughout the world. The present study analyzed the pedigree and herd records of the donkey Asinina de Miranda breed (RAM), identifying genealogical and human factors that may affect the breed genetic diversity in the future and suggesting suitable strategies to breed preservation, early on the conservation program. The breeding rate was very low, with a ratio of foaling/live animals of 0.23 (178/760). The estimated number of founders and ancestors contributing to the reference population was 128 and 121. The number of founder herds in the reference population was 64, with an effective number of founder herds for the reference population of 7.6. The mean age of herd owners was 65.50 ± 0.884 years, with a negative association among the herd size and owner's age (P<0.001). In contrast, the size of the herd and the ownership of a male were both positively associated (P<0.001) with the herd number of in-born foals. Both the owners' age and the herd location (RAM home region v. dispersal region) were negatively associated with the foaling number (P<0.001). The main identified risk factors were: low breeding rates; low number of males and their unequal contribution to the genetic pool; unequal contribution of the herds to genetic pool; and advanced age of herd owners.

  16. Prevalence of antibodies against Chlamydophila abortus and Coxiella burnetii in goat herds in Poland.

    Science.gov (United States)

    Czopowicz, M; Kaba, J; Szaluś-Jordanow, O; Nowicki, M; Witkowski, L; Nowicka, D; Frymus, T

    2010-01-01

    An epidemiological study was carried out to determine the herd prevalence of Chlamydophila abortus and Coxiella burnetii antibodies in goats covered by a milk recording program in Poland. The survey took place in 2007 and 48 herds located in different parts of the country were involved. A representative sample from each herd was taken by a simple random sampling allowing to detect seropositivity of a herd on a 95% level of confidence. In total 918 goats were tested for specific antibodies against both germs with the use of enzyme-linked immunosorbent assays. In addition, history of reproductive failures was recorded in these herds. The survey revealed that the herd prevalence of C. abortus was 4.2% (2 herds) while no C. burnetii antibodies were found. Abortions were reported to be a problem in 80% of herds while repeating estrus was encountered in 46% of herds. Reproductive failure concerned two seropositive herds as well. Since the germ is present in the population, it has to be taken into consideration in diagnostic process. Nevertheless, the results of the present study indicate that C. abortus infection occurs infrequently in Polish goats. As no antibodies against C. burnetii were detected in the screened sample the risk of goat-to-human transmission of both bacteria in Poland seems to be very low.

  17. Mass vaccination and herd immunity: cattle and buffalo.

    Science.gov (United States)

    Roeder, P L; Taylor, W P

    2007-04-01

    The design of effective programmes for emergency response to incursion of epizootic diseases of cattle, for exclusion of such diseases and for implementation of progressive control in enzootic situations leading to eventual virus elimination, is currently largely empirical. This needs to be remedied to provide more cost-effective use of vaccines and more effective control. At population level, protective effects of immunisation can extend well beyond the individual, influencing the dynamics of viral propagation within the whole population, non-vaccinated as well as vaccinated. This concept of herd immunity and application of the resulting epidemiological principles, combined with experience gained from disease control programmes such as the Global Rinderpest Eradication Programme has much to offer in designing effective science-based control programmes. This paper explores practical exploitation of the herd immunity principle by considering some of the factors which militate against mass vaccination achieving effective levels of herd immunity and, with these in mind, suggesting ways to optimise the efficiency of mass vaccination programmes.

  18. Herds on the Move: Transformations in Tibetan Nomadic Pastoral Systems

    Directory of Open Access Journals (Sweden)

    Daniel Miller

    2015-07-01

    Full Text Available Daniel Miller. 2015. Herds on the Move: Transformations in Tibetan Nomadic Pastoral Systems in Gerald Roche, Keith Dede, Fernanda Pirie, and Benedict Copps (eds Asian Highlands Perspectives 37 Centering the Local, A Festschrift for Dr. Charles Kevin Stuart on the Occasion of his Sixtieth Birthday, 207-220. Eight thousand years ago, an event took place that changed the world. In the mountain valleys where modern Iraq, Turkey, and Iran intersect, some enterprising farmers determined that it was easier to make a living by specializing in raising livestock than growing crops. They left their farms and moved into the grasslands, herding their animals over a vast area, traveling to different seasonal pastures throughout the year with their belongings and homes rolled up and carried on the backs of animals. This was the first stage of what later became known as nomadic pastoralism, and the people that followed the herds were called nomadic pastoralists, or simply, nomads. Sheep and goats were first domesticated about 10,500 years ago, but it took another couple thousand years before some hardy farmers, who raised both crops and livestock, ventured into the steppes and developed a culture that specialized in raising livestock. Since they first left the fertile, agricultural valleys with their livestock and moved into the steppes, they have been out there on the edge of civilization – out where the vast rolling grasslands meet the purple haze of the horizon – living a life that many aspire to, but which few were able to follow.

  19. A case-control study of risk factors for bovine cysticercosis in Danish cattle herds.

    Science.gov (United States)

    Calvo-Artavia, F F; Nielsen, L R; Dahl, J; Clausen, D M; Graumann, A M; Alban, L

    2013-06-01

    Bovine cysticercosis (BC) is a zoonotic, parasitic infection in cattle. Under the current EU meat inspection regulation, every single carcass from all bovines above 6 weeks of age is examined for BC. This method is costly and makes more sense in countries with higher number of BC-infected animals than in countries with few lightly infected cases per year. The aim of the present case-control study was to quantify associations between potential herd-level risk factors and BC in Danish cattle herds. Risk factors can be used in the design of a risk-based meat inspection system targeted towards the animals with the highest risk of BC. Cases (n = 77) included herds that hosted at least one animal diagnosed with BC at meat inspection, from 2006 to 2010. Control herds (n = 231) consisted of randomly selected herds that had not hosted any animals diagnosed with BC between 2004 and 2010. The answers from a questionnaire and register data from the Danish Cattle Database were grouped into meaningful variables and used to investigate the risk factors for BC using a multivariable logistic regression model. Case herds were almost three times more likely than control herds to let all or most animals out grazing. Case herds were more than five times more likely than control herds to allow their animals access to risky water sources with sewage treatment plant effluent in proximity. Case herds were also more likely to share machinery or hire contractors than control herds. The risk decreased with increasing herd size probably because the larger herds generally tend to keep cattle indoors in Denmark. The results are useful to guide future data recording that can be supplied by the farmer as food chain information and then be used for differentiated meat inspection in low- and high-risk groups, enabling development of risk-based meat inspection systems.

  20. Within- and between-herd prevalence variation of Mycobacterium avium subsp. paratuberculosis infection among control programme herds in Denmark (2011-2013)

    DEFF Research Database (Denmark)

    Verdugo, Cristobal; Toft, Nils; Nielsen, Søren

    2015-01-01

    included in the analysis, and one annual milk-ELISA test of all lactating cows present in such herds was considered. A Bayesian latent class model was used to obtain HTP and TP posterior distributions for each year. The model adjusts for uncertainty in age-specific test sensitivity and prior prevalence......This study aimed to estimate the between- (HTP) and within- (TP) herd true prevalence distribution of Mycobacterium avium subsp. paratuberculosis (MAP) infection in dairy cattle herds participating in the Danish MAP control programme. All herds enrolled in the programme between 2011 and 2013 were...... estimates. Bayesian posterior probabilities were computed in order to compare prevalence between the years. A total of 665,700 samples were included in the study, from 221,914, 224,040, and 220,466 cows sourced from 1138, 1112, and 1059 herds in years 2011, 2012, and 2013, respectively. In that period, HTP...

  1. Bacteriological etiology and treatment of mastitis in Finnish dairy herds.

    Science.gov (United States)

    Vakkamäki, Johanna; Taponen, Suvi; Heikkilä, Anna-Maija; Pyörälä, Satu

    2017-05-25

    The Finnish dairy herd recording system maintains production and health records of cows and herds. Veterinarians and farmers register veterinary treatments in the system. Milk samples for microbiological analysis are routinely taken from mastitic cows. The laboratory of the largest dairy company in Finland, Valio Ltd., analyzes most samples using real-time PCR. This study addressed pathogen-specific microbiological data and treatment and culling records, in combination with cow and herd characteristics, from the Finnish dairy herd recording system during 2010-2012. The data derived from 240,067 quarter milk samples from 93,529 dairy cows with mastitis; 238,235 cows from the same herds served as the control group. No target pathogen DNA was detected in 12% of the samples. In 49% of the positive samples, only one target species and in 19%, two species with one dominant species were present. The most common species in the samples with a single species only were coagulase-negative staphylococci (CNS) (43%), followed by Staphylococcus aureus (21%), Streptococcus uberis (9%), Streptococcus dysgalactiae (8%), Corynebacterium bovis (7%), and Escherichia coli (5%). On average, 36% of the study cows and 6% of the control cows had recorded mastitis treatments during lactation. The corresponding proportions were 16 and 6% at drying-off. For more than 75% of the treatments during lactation, diagnosis was acute clinical mastitis. In the milk samples from cows with a recorded mastitis treatment during lactation, CNS and S. aureus were most common, followed by streptococci. Altogether, 48% of the cows were culled during the study. Mastitis was reported as the most common reason to cull; 49% of study cows and 18% of control cows were culled because of mastitis. Culling was most likely if S. aureus was detected in the milk sample submitted during the culling year. The PCR test has proven to be an applicable method also for large-scale use in bacterial diagnostics. In the present

  2. Herd level husbandry factors associated with the serological Salmonella prevalence in finishing pig herds in The Netherlands.

    Science.gov (United States)

    van der Wolf, P J; Wolbers, W B; Elbers, A R; van der Heijden, H M; Koppen, J M; Hunneman, W A; van Schie, F W; Tielen, M J

    2001-02-12

    A national program to reduce Salmonella in pork and pork products should include monitoring and intervention at farm level. To develop an adequate intervention strategy at farm level, risk factors for Salmonella infections in finishing pigs have to be determined. In this study, blood samples were collected randomly at two slaughterhouses from slaughter pigs. Samples were tested by the Dutch Salmonella ELISA, based on the O-antigens 1, 4, 5, 6, 7 and 12, using a cut-off of OD%=10. This ELISA has been calibrated against the Danish ELISA to give comparable results. Workers from herds from which at least forty blood samples had been collected, were asked to participate in a questionnaire. In total, 353 questionnaires were obtained and analysed. Significant risk factors associated with the proportion of seropositive samples were identified by multiple linear logistic regression. The feeding of a complete liquid feed containing fermented by-products and the omission of disinfection after pressure washing a compartment as part of an all-in/all-out procedure, were both associated with a lower Salmonella seroprevalence. A small to moderate herd size (feed, or herds which had more than 16% of the livers of their pigs condemned at the slaughterhouse as a result of white spots were associated with a higher Salmonella seroprevalence. Hypothetical intervention strategies based on these risk factors can be studied for their effect on the Salmonella seroprevalence and practical applicability in field studies.

  3. Modelagem de efeitos genéticos e ambientais que influenciam o peso à desmama de bezerros mestiços Charolês-Zebu Modeling of genetic and environmental effects affecting the weaning weight of Charolais-Zebu crossbred calves

    Directory of Open Access Journals (Sweden)

    Fábio Luiz Buranelo Toral

    2011-11-01

    Full Text Available Este trabalho foi realizado com o objetivo de avaliar alternativas para modelagem de efeitos genéticos e ambientais que influenciam o peso à desmama de bezerros mestiços Charolês-Zebu. Foram utilizados os dados de peso à desmama de 56.965 bezerros, com percentuais de alelos de origem da raça Charolesa variando entre 23% e 66%. Os modelos considerados diferiram quanto à inclusão de efeitos genéticos aditivos e não-aditivos médios, individuais e maternos, bem como quanto à maneira de modelar estes efeitos (regressão múltipla ou variável classificatória. Também foi avaliada a inclusão da interação entre o grupo genético do bezerro e seu grupo de contemporâneos, como um efeito aleatório não correlacionado. De acordo com os critérios de ajuste utilizados, a interação entre o grupo genético e o grupo de contemporâneos representa parte significativa da variação observada para o peso à desmama de bezerros Charolês-Zebu e os efeitos dos percentuais de alelos de origem da raça Charolesa e de heterozigoses, individuais e maternos, podem ser modelados por meio da utilização de regressão múltipla.This study was carried out to evaluate some alternatives for modeling of genetic and environmental effects influencing the weaning weight of Charolais-Zebu crossbred calves. The weaning weight data of 56,965 calves with alleles' percentage from the Charolais breed varying from 23% to 66% were used. The models under comparison differed for the inclusion of the individual and maternal additive and non-additive genetic effects, as well as the way to model those effects (multiple regression or discrete variable. The inclusion of the interaction between the calf genetic group and its contemporary group was also evaluated as a random uncorrelated effect. The adjustment criteria pointed out the interaction between the calf genetic group and its contemporary group to represent a significant part of the variation observed for the weaning

  4. Age-structured dynamic, stochastic and mechanistic simulation model of Salmonella Dublin infection within dairy herds

    DEFF Research Database (Denmark)

    Nielsen, Liza Rosenbaum; Kudahl, Anne Margrethe Braad; Østergaard, Søren

    2012-01-01

    of the six age-groups; 2) S. Dublin incidence and number of animals in each infection state; and 3) S. Dublin related morbidity and mortality in the acutely infected animals. The effects of introducing one infectious heifer on the risk of spread of S. Dublin within the herd and on the duration of infection...... for the individual animals in each of the six age groups in the herd. The hygiene level was highly influential on the probability that the infection spread within the herd, duration of infection and epidemic size. The herd susceptibility level was also influential, but not likely to provide sufficient prevention...... the probability of extinction. In general, disease and mortality patterns followed epidemic waves in the herds. However, an interesting pattern was seen for acute infections and abortions in adult cattle after the first 2 years of infection in herds with poor hygiene and high susceptibility. Repeated infections...

  5. Testing of bulk tank milk for Salmonella Dublin infection in Danish dairy herds

    DEFF Research Database (Denmark)

    Wedderkopp, A.; Stroger, U.; Bitsch, V.;

    2001-01-01

    of being test-negative in the third test round was 0.926 for a herd with 2 previous test-negative results. It was concluded that the investigated ELISA method was in general accordance with the cases of clinical S. Dublin infection recorded. and that the method has a potential for national screening......The usefulness of enzyme-linked immunosorbent assay (ELISA) was investigated as a simple method to screen for Salmonella Dublin infection in dairy herds, examining bulk tank milk samples for lipopolysaccharide (O:1,9,12) antibodies. The cut-off value for the ELISA on bulk tank milk was established...... based on individual milk samples (n = 2887) and bulk tank milk from 52 herds. Bulk tank milk samples (n = 5108) were collected from 1464 dairy herds located in 19 different areas. About 10% of the dairy herds in Denmark participated in the study. The percentage of herds changing from test...

  6. Mortality in Danish Swine herds: Spatio-temporal clusters and risk factors

    DEFF Research Database (Denmark)

    Lopes Antunes, Ana Carolina; Ersbøll, Annette Kjær; Bihrmann, Kristine

    2017-01-01

    The aim of this study was to explore spatio-temporal mortality patterns in Danish swine herds from December 2013 to October 2015, and to discuss the use of mortality data for syndromic surveillance in Denmark. Although it has previously been assessed within the context of syndromic surveillance......, the value of mortality data generated on a regular and mandatory basis from all swine herds remains unexplored in terms of swine surveillance in Denmark. A total of 5010 farms were included in the analysis, corresponding to 1896 weaner herds, 1490 sow herds and 3839 finisher herds. The spatio...... indicate welfare and disease issues, while multiple-herd clusters could suggest the presence of infectious diseases within the cluster area. The impact of farm type is linked to the fact that larger farms specialize in only one age group, with high biosecurity and more specialized personnel...

  7. Clustering Effect on the Evolution of Cooperation in a Herding Snowdrift Game

    Institute of Scientific and Technical Information of China (English)

    CHEN Guang; QIU Tian; WU Xiao-Run

    2009-01-01

    We study the evolution of cooperation for two cluster breaking mechanisms in a herding snowdrift game.The cooperative behavior is observed to be related to the duster size.A negative dependence of the payoff parameter r on cooperative behavior is discovered.For a low r,herding helps promote the cooperation,whereas for a high r,herding tends to prevent cooperative behavior.

  8. Sow rearing in north Italy: I. analysis of technical and productive characteristics of different herds

    Directory of Open Access Journals (Sweden)

    S. Schiavon

    2010-01-01

    Full Text Available There is a lack of information about reference values for the main productive and reproductive indexes for the sow herds in North Italy. This investigation was aimed to collect data from different kind of sow herds placed in the Veneto Region, in order to achieve representative values, in terms of mean and variability, for the main indexes of productivity: herd composition, feed consumption and feed composition.

  9. Sow rearing in north Italy: I. analysis of technical and productive characteristics of different herds

    OpenAIRE

    Schiavon, S.; F. Tagliapietra; C. Ceolin

    2010-01-01

    There is a lack of information about reference values for the main productive and reproductive indexes for the sow herds in North Italy. This investigation was aimed to collect data from different kind of sow herds placed in the Veneto Region, in order to achieve representative values, in terms of mean and variability, for the main indexes of productivity: herd composition, feed consumption and feed composition.

  10. Risk factors for MRSA in fattening pig herds - a meta-analysis using pooled data.

    Science.gov (United States)

    Fromm, Sabine; Beißwanger, Elena; Käsbohrer, Annemarie; Tenhagen, Bernd-Alois

    2014-11-01

    The importance of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) as an infectious agent for humans has increased in recent years in Germany. Although it is well known that the prevalence of MRSA in pig farms is high, risk factors for the presence of MRSA in herds of fattening pigs are still poorly understood. The aim of this study was to evaluate available data from previous studies on MRSA in fattening pigs in a meta-analysis to answer the question: What are the factors associated with the occurrence of MRSA in fattening pig herds? The studies on MRSA in pigs that were identified by literature research were heterogeneous with respect to the risk factors investigated and the type of herds focused on. Therefore we decided to carry out a pooling analysis on herd level rather than a typical meta-analysis. Eligible herd data were identified based on the published literature and communication with the authors. The final data set covered 400 fattening pig herds from 10 different studies and 12 risk factors. The prevalence of MRSA in the 400 fattening pig herds was 53.5%. Data were analyzed using generalized estimating equations (GEE). The resulting multivariate model confirmed previously identified risk factors for MRSA in pig herds (herd size and herd type). It also identified further risk factors: group treatment of fattening pigs with antimicrobial drugs (OR=1.79) and housing fattening pig herds on at least partially slatted floors (OR=2.39) compared to plain floor. In contrast, according to the model, fattening pig herds on farms keeping other livestock along with pigs were less likely to harbor MRSA (OR=0.54). The results underline the benefits from a pooling analysis and cooperative re-evaluation of published data.

  11. Herd level antimicrobial resistance in beef calves in Switzerland 1986 through 2011

    OpenAIRE

    Hässig, Michael; Eugster, Sabine; Lewis, Fraser I.

    2014-01-01

    The increasing emergence of antimicrobial resistance in food animals is a growing global concern and is closely linked to animal husbandry practices. In this study we describe the changement of antimicrobial resistance in beef calf production in Switzerland from 1986 through 2011. Data were collected from farms with known calf herd problems, such as diarrhoea or pneumonia, along with antimicrobial resistance from those herds. The Herd Health section of the University of Zurich visited each...

  12. Herd level antimicrobial resistance in beef calves in Switzerland 1986 through 2011

    OpenAIRE

    Hässig, Michael; Eugster, Sarina; Lewis, Frazer Iain

    2014-01-01

    The increasing emergence of antimicrobial resistance in food animals is a growing global concern and is closely linked to animal husbandry practices. In this study we describe the changement of antimicrobial resistance in beef calf production in Switzerland from 1986 through 2011. Data were collected from farms with known calf herd problems, such as diarrhoea or pneumonia, along with antimicrobial resistance from those herds. The Herd Health Section of the University of Zu-rich visited each f...

  13. Stress Resilience among Border Mexican American Women

    Science.gov (United States)

    Guinn, Bobby; Vincent, Vern; Dugas, Donna

    2009-01-01

    The purpose of this study was to identify factors distinguishing Mexican American women living near the U.S.-Mexican border who are resilient to the experience of stress from those who are not. The study sample consisted of 418 participants ranging in age from 20 to 61 years. Data were gathered through a self-report survey instrument composed of…

  14. Stress Resilience among Border Mexican American Women

    Science.gov (United States)

    Guinn, Bobby; Vincent, Vern; Dugas, Donna

    2009-01-01

    The purpose of this study was to identify factors distinguishing Mexican American women living near the U.S.-Mexican border who are resilient to the experience of stress from those who are not. The study sample consisted of 418 participants ranging in age from 20 to 61 years. Data were gathered through a self-report survey instrument composed of…

  15. Women as Leaders in Mexican Education.

    Science.gov (United States)

    Cortina, Regina

    1989-01-01

    Examines the role of women in Mexican public education leadership. Teaching is a desirable career for Mexican women, but gender differentiated education, training, cultural expectations, family responsibilities, and lack of affirmative government policy inhibit women's professional advancement in the centralized federal bureaucracy that manages…

  16. Mexican Managers' Perceptions of Cultural Competence.

    Science.gov (United States)

    Grosse, Christine Uber

    2001-01-01

    Global managers in Mexico identified what their U.S. counterparts should know about Mexican culture to do business effectively. Suggested Mexican and U.S.cultures are exact opposites in many respects. Discussed differences in building business relationships, attitudes toward time, family and religious values, communication patterns, and…

  17. A Turnover Model for the Mexican Maquiladoras.

    Science.gov (United States)

    Maertz, Carl P.; Stevens, Michael J.; Campion, Michael A.

    2003-01-01

    From interviews with 47 Mexican maquiladora workers, a model of voluntary turnover was created and compared with models from the United States, Canada, England, and Australia. Despite similarities, the cultural and economic environment affected the precise content of antecedents in the Mexican model. (Contains 63 references.) (SK)

  18. Forecasting U.S. Car Sales and Car Registrations in Japan: Rationality, Accuracy and Herding

    DEFF Research Database (Denmark)

    Stadtmann, Georg; Rülke, Jan; Pierdzioch, Christian

    2011-01-01

    We analyze forecasts of car sales in the U.S. and forecasts of car registrations in Japan. We document a substantial heterogeneity of forecasts, and we show that, based on traditional criteria, forecasts are neither rational nor unbiased. We also report that forecasters anti-herd, that is......, forecasters seem to intentionally scatter their forecasts around a consensus forecast. We further show that cross-sectional heterogeneity of forecasts with regard to anti-herding transmits onto cross-sectional heterogeneity of forecast accuracy. Specifically, we document that forecasters who herd provide more...... accurate forecasts than their colleagues who anti-herd....

  19. Mean effective sensitivity for Mycobacterium avium subsp paratuberculosis infection in cattle herds

    DEFF Research Database (Denmark)

    Kirkeby, Carsten; Græsbøll, Kaare; Hisham Beshara Halasa, Tariq;

    2015-01-01

    Background: Mycobacterium avium subsp. paratuberculosis (MAP) infections in cattle are generally challenging to detect and cost-effective test strategies are consequently difficult to identify. MAP-specific antibody ELISAs for milk and serum are relatively inexpensive, but their utility...... within and between groups, and in some groups we found a bimodal distribution of MES. Dairy herds generally showed higher MES than non-dairy herds. Dairy herds in a control programme for paratuberculosis showed a MES similar to all other dairy herds from which animals >2.0 years were tested (both groups...

  20. Associations of Neospora caninum seropositivity with gestation number and pregnancy outcome in Danish dairy herds

    DEFF Research Database (Denmark)

    Jensen, Anette Møllegaard; Bjorkman, C.; Kjeldsen, A.M.;

    1999-01-01

    The prevalence and distribution of seropositivity towards the protozoan parasite Neospora caninum were studied in single blood samples from 1561 cows from 31 Danish dairy herds. Blood samples were analysed by an indirect enzyme-linked immunoassay and an indirect fluorescent-antibody test......, Seroprevalence in 15 herds with previous abortions assigned to neosporosis ranged from I% to 58%, with a mean frequency of 22%. In eight out of 16 herds without a history of N. caninum related abortions, no seroreactors were found. In the remaining eight herds, the seroprevalence ranged from 6% to 59...

  1. Association between bovine-leukosis virus seroprevalence and herd-level productivity on US dairy farms.

    Science.gov (United States)

    Ott, S L; Johnson, R; Wells, S J

    2003-12-12

    Bovine-leukosis virus (BLV; also termed 'bovine-leukemia virus') is a retrovirus that primarily affects lymphoid tissue of dairy and beef cattle. Our objective was to investigate the association between BLV infection and annual value of production (AVP) on dairy herds within the United States, as part of the USDA National Animal Health Monitoring System's 1996 dairy study. 1006 herds (in 20 states) with at least 30 dairy cows were interviewed during 1996. The agar-gel immunodiffusion test was used to detect serum antibodies to BLV. 10-40 cows from each herd were tested and each tested cow was classified as negative or positive based on results of a single test. A multivariable regression model was used with the 976 herds with complete data for analysis. When compared to herds with no test-positive cows, herds with test-positive cows produced 218 kg per cow (i.e. 3%) less milk. The average reduction in AVP was $59 per cow for test-positive herds relative to test-negative herds. For the dairy industry as a whole, BLV seropositivity was associated with loss to producers of $285 million and $240 million for consumers. Most of this $525 million industry loss was due to reduced milk production in test-positive herds.

  2. Serological study of bovine herpes virus type 1 in dairy herds of Hamedan province, Iran

    Directory of Open Access Journals (Sweden)

    Aliasghar Bahari

    2013-06-01

    Full Text Available A cross-sectional study with a random cluster sampling design was carried out to estimate the seroprevalence of bovine herpesvirus type 1 (BHV-1 in non-vaccinated dairy herds in Hamedan province, west of Iran. Simple random sampling was used for selection of cattle in each herd. Informative data about each herd and selected animals were recorded by the farm manager in a provided questionnaire. Blood samples were collected from 492 animals in 41 industrial herds. A commercial indirect ELISA test was used to determine the seropositivity against BHV-1. The individual and herd seroprevalence for BHV-1 were 58.74% and 82.93%, respectively. The intra-herd prevalences were ranged from 16.70% to 100%. Geographical characteristics of Hamedan province may explain the high sero- prevalence rates found in this study compared to those of others obtained from different parts of the country. The proportion of seropositive cows were increased with age (p <0.05. Animals from large and moderate sized herds had higher odds of seropositivity than those of small size herds. These findings could be related to the presence of a considerable number of BHV-1 carriers in this region. The high herd and animal prevalence found in the present study suggested necessity of implementing an intensive control program for reducing BHV-1 infection rates.

  3. Control and eradication programme of enzootic bovine leucosis (EBL) from selected dairy herds in Turkey.

    Science.gov (United States)

    Burgu, I; Alkan, F; Karaoglu, T; Bilge-Dagalp, S; Can-Sahna, K; Güngör, B; Demir, B

    2005-07-01

    Serum samples of 15,909 cattle from 31 dairy herds located in various regions of Turkey were tested for the presence of antibodies against bovine leucosis virus (BLV) using Agar Gel Immuno-diffusion technique (AGID). 48.3% (15/31) of the herds had seropositive animals and positivity rates were detected from 0.5-34.4% in these herds. In an EBL control/eradication programme all seropositive animals were culled in the infected herds. Thereafter, a total of 74,347 sera were tested for the presence of BLV specific antibodies. The serological results and detail of EBL control/eradication programme were shown in this paper.

  4. High female mortality resulting in herd collapse in free-ranging domesticated reindeer (Rangifer tarandus tarandus in Sweden.

    Directory of Open Access Journals (Sweden)

    Birgitta Åhman

    Full Text Available Reindeer herding in Sweden is a form of pastoralism practised by the indigenous Sámi population. The economy is mainly based on meat production. Herd size is generally regulated by harvest in order not to overuse grazing ranges and keep a productive herd. Nonetheless, herd growth and room for harvest is currently small in many areas. Negative herd growth and low harvest rate were observed in one of two herds in a reindeer herding community in Central Sweden. The herds (A and B used the same ranges from April until the autumn gathering in October-December, but were separated on different ranges over winter. Analyses of capture-recapture for 723 adult female reindeer over five years (2007-2012 revealed high annual losses (7.1% and 18.4%, for herd A and B respectively. A continuing decline in the total reindeer number in herd B demonstrated an inability to maintain the herd size in spite of a very small harvest. An estimated breakpoint for when herd size cannot be kept stable confirmed that the observed female mortality rate in herd B represented a state of herd collapse. Lower calving success in herd B compared to A indicated differences in winter foraging conditions. However, we found only minor differences in animal body condition between the herds in autumn. We found no evidence that a lower autumn body mass generally increased the risk for a female of dying from one autumn to the next. We conclude that the prime driver of the on-going collapse of herd B is not high animal density or poor body condition. Accidents or disease seem unlikely as major causes of mortality. Predation, primarily by lynx and wolverine, appears to be the most plausible reason for the high female mortality and state of collapse in the studied reindeer herding community.

  5. Herd-level risk factors for Campylobacter fetus infection, Brucella seropositivity and within-herd seroprevalence of brucellosis in cattle in northern Nigeria.

    Science.gov (United States)

    Mai, H M; Irons, P C; Kabir, J; Thompson, P N

    2013-09-01

    Brucellosis and campylobacteriosis are economically important diseases affecting bovine reproductive efficiency in Nigeria. A questionnaire-based survey was conducted in 271 cattle herds in Adamawa, Kaduna and Kano states of northern Nigeria using multistage cluster sampling. Serum from 4745 mature animals was tested for Brucella antibodies using the Rose-Bengal plate test and positives were confirmed in series-testing protocol using competitive enzyme-linked immunosorbent assay. Preputial scrapings from 602 bulls were tested using culture and identification for Campylobacter fetus. For each disease, a herd was classified as positive if one or more animals tested positive. For each herd, information on potential managemental and environmental risk factors was collected through a questionnaire administered during an interview with the manager, owner or herdsman. Multiple logistic regression models were used to model the odds of herd infection for each disease. A zero-inflated Poisson model was used to model the count of Brucella-positive animals within herds, with the number tested as an exposure variable. The presence of small ruminants (sheep and/or goats) on the same farm, and buying-in of >3 new animals in the previous year or failure to practice quarantine were associated with increased odds of herd-level campylobacteriosis and brucellosis, as well as increased within-herd counts of Brucella-positive animals. In addition, high rainfall, initial acquisition of animals from markets, practice of gynaecological examination and failure to practice herd prophylactic measures were positively associated with the odds of C. fetus infection in the herd. Herd size of >15, pastoral management system and presence of handling facility on the farm were associated with increased odds, and gynaecological examination with reduced odds of herd-level Brucella seropositivity. Furthermore, the zero-inflated Poisson model showed that borrowing or sharing of bulls was associated with

  6. Herd prevalence of Salmonella spp. in Danish pig herds after implementation of the Danish Salmonella Control Program with reference to a pre-implementation study

    DEFF Research Database (Denmark)

    Christensen, Jette; Baggesen, Dorte Lau; Nielsen, Bent

    2002-01-01

    The problems addressed are: (1) comparison of prevalences of Salmonella spp. in different herd types in the Danish pig population after implementation of the Danish Salmonella Control Program (DSCP), and (2) to make a reference to a study from 1993/1994 (pre-implementation) with a discussion...... of possible biases when diagnostic methods differ slightly. The objectives were to present the prevalences of Salmonella spp., Salmonella Typhimurium, and multiresistant S. Typhimurium DT104 in Danish pig herds in 1998. Further, to discuss how herd prevalences may be compared to a previous study...

  7. First description of Bartonella bovis in cattle herds in Israel.

    Science.gov (United States)

    Rudoler, Nir; Rasis, Michal; Sharir, Benny; Novikov, Anna; Shapira, Gregory; Giladi, Michael

    2014-09-17

    Bartonella bovis has been described in beef and dairy cattle worldwide, however the reported prevalence rates are inconsistent, with large variability across studies (0-89%). This study describes the first isolation and characterization of B. bovis among cattle herds in the Middle East. Blood samples from two beef cattle herds (each sampled thrice) and one dairy herd (sampled twice) in Israel were collected during a 16-months period. Overall, 71 of 95 blood samples (75%) grew Bartonella sp., with prevalence of 78% and 59% in beef and dairy cattle, respectively. High level bacteremia (≥100,000 colony forming units/mL) was detected in 25 specimens (26%). Such high-level bacteremia has never been reported in cattle. Two dairy cows and one beef cow remained bacteremic when tested 60 or 120 days apart, respectively, suggesting that cattle may have persistent bacteremia. One third of animals were infested with ticks. Sequence analysis of a gltA fragment of 32 bacterial isolates from 32 animals revealed 100% homology to B. bovis. Species identification was confirmed by sequence analysis of the rpoB gene. Phylogenetic analysis based on the concatenated sequences of gltA and rpoB demonstrated that the isolates described herein form a monophyletic group with B. bovis strains originating from cattle worldwide. Taken together, the high prevalence of bacteremia, including high-level bacteremia, in beef and dairy cattle, the potential to develop prolonged bacteremia, the exposure of cattle to arthropod vectors, and proximity of infected animals to humans, make B. bovis a potential zoonotic agent.

  8. Loser cows in Danish dairy herds: definition, prevalence and consequences.

    Science.gov (United States)

    Thomsen, Peter T; Østergaard, Søren; Sørensen, Jan Tind; Houe, Hans

    2007-05-16

    During the last few years, many Danish dairy farmers have expressed increasing concerns regarding a group of cows, which we have chosen to term 'loser cows'. Until now, a loser cow has not been described scientifically. We defined a loser cow on the basis of a clinical examination of the cow. A total of 15,151 clinical examinations were made on 6,451 individual cows from 39 randomly selected, large Danish dairy herds with loose-housing systems using a clinical protocol. Scores for the clinical signs lameness, body condition, hock lesions, other cutaneous lesions, vaginal discharge, condition of hair coat and general condition were converted into a loser cow score. Cows with a loser cow score of 8 or more were classified as loser cows. The overall prevalence of loser cows was 2.15%, 4.50% and 2.98% during the first, second and third round of herd visits, respectively. The associations between the loser cow state and milk production, mortality, morbidity, culling and workload for the farmer were evaluated using data from herd visits and from the Danish Cattle Database and a number of different statistical techniques. It was concluded that the loser cow state has significant negative consequences for both the farmer and the cow. On average, loser cows yielded 0.61 to 2.24 kg energy corrected milk less per day than non-loser cows depending on parity. Hazard ratio for death or euthanasia was 5.69 for loser cows compared to non-loser cows. Incidence rate ratio for disease treatments was 0.69 for non-loser cows compared to loser cows. Loser cows were often culled in an 'unfavourable' way and generally caused extra workload for the farmer. A simplified version of the loser cow score was evaluated and is recommended for future research and use in practice.

  9. The Fortymile caribou herd: novel proposed management and relevant biology, 1992-1997

    Directory of Open Access Journals (Sweden)

    Rodney D. Boertje

    2000-04-01

    Full Text Available A diverse, international Fortymile Planning Team wrote a novel Fortymile caribou herd {Rangifer tarandus granti Management Plan in 1995 (Boertje & Gardner, 1996: 56-77. The primary goal of this plan is to begin restoring the Fortymile herd to its former range; >70% of the herd's former range was abandoned as herd size declined. Specific objectives call for increasing the Fortymile herd by at least 5-10% annually from 1998-2002. We describe demographics of the herd, factors limiting the herd, and condition of the herd and range during 1992-1997. These data were useful in proposing management actions for the herd and should be instrumental in future evaluations of the plan's actions. The following points summarize herd biology relevant to management proposed by the Fortymile Planning Team: 1. Herd numbers remained relatively stable during 1990-1995 (about 22 000-23 000 caribou. On 21 June 1996 we counted about 900 additional caribou in the herd, probably a result of increased pregnancy rates in 1996. On 26 June 1997 we counted about 2500 additional caribou in the herd, probably a result of recruitment of the abundant 1996 calves and excellent early survival of the 1997 calves. The Team deemed that implementing management actions during a period of natural growth would be opportune. 2. Wolf (Canis lupus and grizzly bear (Ursus arctos predation were the most important sources of mortality, despite over a decade of the most liberal regulations in the state for harvesting of wolves and grizzly bears. Wolves were the most important predator. Wolves killed between 2000 and 3000 caribou calves annually during this study and between 1000 and 2300 older caribou; 1200-1900 calves were killed from May through September. No significant differences in annual wolf predation rates on calves or adults were observed between 1994 and early winter 1997. Reducing wolf predation was judged by the Team to be the most manageable way to help hasten or stimulate

  10. Helping Mexican and Mexican-American Students in the Schools of the East Side Union High School District.

    Science.gov (United States)

    Miller, Robert

    This document provides information about schools in Mexico and suggests ways that U.S. schools can use this information to improve education for Mexican and Mexican American students. Chapter 1 describes the Mexican educational system as a vantage point for understanding the expectations of Mexican parents in the United States. This chapter covers…

  11. The SIR Epidemiology Model in Predicting Herd Immunity

    Directory of Open Access Journals (Sweden)

    Joanna Nicho

    2010-01-01

    Full Text Available The Simple Epidemic Model uses three states to describe the spread of an infection: the susceptible (S, the infected (I, and the recovered (R. This model follows the trend of an infection over time and can predict whether an infection will spread. Using this model, epidemiologists may calculate the percentage of the population that needs to be vaccinated in order to provide a population immunity from a disease. This study will compare the vaccination percentage required for herd immunity to measles, mumps, and rubella against the current percentage of vaccinated individuals.

  12. Reproductive Systems for North American Beef Cattle Herds.

    Science.gov (United States)

    Larson, Robert L; White, Brad J

    2016-07-01

    A systems approach to beef cattle reproduction facilitates evaluating the flow of cattle through the herd population based on temporal changes in reproductive and production state. The previous years' timing of calving has either a positive or negative effect on the present year's reproductive success. In order to create and maintain high reproductive success, one must focus on: developing heifers to become pregnant early in the breeding season, ensuring bull breeding soundness, aligning the calving period with optimal resource availability, managing forage and supplementation to ensure good cow body condition going into calving, and minimizing reproductive losses due to disease.

  13. Pertussis: herd immunity and vaccination coverage in St Lucia.

    Science.gov (United States)

    Cooper, E; Fitch, L

    1983-11-12

    In a single complete epidemic in St Lucia, an island too small to support constant clinical pertussis, the pertussis case rates in small communities (villages and small towns) with differing levels of vaccination coverage of young children were compared. The association between greater vaccination coverage and greater herd immunity was clear, despite the imperfect protection given to individuals. An analysis in terms of population dynamics is evidence against the theory that endemic subclinical pertussis maintains transmission in a highly vaccinated population. We suggest that with a homogeneous vaccination coverage of 80% of 2-year-old children pertussis might be eradicated from the island, and that this is a practicable experiment.

  14. Three-state herding model of the financial markets

    Science.gov (United States)

    Kononovicius, A.; Gontis, V.

    2013-01-01

    We propose a Markov jump process with the three-state herding interaction. We see our approach as an agent-based model for the financial markets. Under certain assumptions this agent-based model can be related to the stochastic description exhibiting sophisticated statistical features. Along with power-law probability density function of the absolute returns we are able to reproduce the fractured power spectral density, which is observed in the high-frequency financial market data. The given example of consistent agent-based and stochastic modeling will provide a background for further developments in the research of complex social systems.

  15. Utility and fertility of herd of milked cattle

    OpenAIRE

    NEJDLOVÁ, Emilie

    2012-01-01

    The aim of this thesis was to analyze milk yield and fertility in dairy cattle herds ? combined (Czech Pied cattle) and dojného utility type (Holstein cattle ) in the same breeding system. Further culling was evaluated, the cost of feeding a day and milk production. Observations were carried out in the company Podhoran Černíkov, as in the time sequence of zootechnical 2 years (1st 10th 2009 - 30 9th 2011). By tracking a total of 310 cows of which 47 cows of Czech Pied cattle C1 (C 100 %), bre...

  16. Pig herd monitoring and undesirable tripping and stepping prevention

    DEFF Research Database (Denmark)

    Gronskyte, Ruta; Clemmensen, Line Katrine Harder; Hviid, Marchen Sonja

    2015-01-01

    at the slaughterhouse and identify undesirable events such as pigs tripping or stepping on each other. In this paper, we monitor pig behavior in color videos recorded during unloading from transportation trucks. We monitor the movement of a pig herd where the pigs enter and leave a surveyed area. The method is based...... performed the unloading of the pigs from the trucks in the available datasets, indicates that the drivers perform significantly differently. Driver 1 has 2.95 times higher odds to have pigs tripping and stepping on each other than the two others, and Driver 2 has 1.11 times higher odds than Driver 3. (C...

  17. Synchronization and Artificial Insemination Strategies in Dairy Herds.

    Science.gov (United States)

    Stevenson, Jeffrey S

    2016-07-01

    Timed artificial insemination (AI) programs are commonly used in the dairy industry for lactating cows, but less so in replacement heifers. Excellent programs using combinations of prostaglandin F2α and gonadotropin-releasing hormone in protocols relying on timed AI without detection of estrus or in protocols that combine timed AI with inseminations performed after detected estrus are able to achieve acceptable pregnancy percentages. In herds with excellent estrus detection, timed AI programs serve as a failsafe system to address cows or heifers not yet inseminated after a defined period of estrus detection.

  18. Neospora caninum in beef herds in New South Wales, Australia. 1: seroprevalence study.

    Science.gov (United States)

    Moloney, B J; Kirkland, P D; Heuer, C

    2017-03-01

    To determine the seroprevalence of Neospora caninum antibodies in beef breeding herds across New South Wales (NSW) and to determine if there are any differences associated with geographic location and other herd-level factors. Cross-sectional survey of beef breeding cows (n = 3298) from 63 properties (approximately 55 cows per herd) sampled randomly from six regions in NSW using a multistage survey design. Samples were tested by ELISA for N. caninum. Seroprevalence was determined at animal and herd levels, using an analysis approach to account for stratification, sample weighting and within-herd clustering. Animal-level seroprevalence ranged from 1.8% to 11.3% across regions and the overall animal seroprevalence for NSW was 5.9%. The mean within-herd seroprevalence was 5.2%. The herd seroprevalence ranged from 50% to 92%, with an overall point estimate for NSW of 63.8% (using ≥ 1 animal positive = herd positive). The within-herd seroprevalence ranged from 1.6% to 32.7% Prevalence and associated confidence limits were adjusted for the design of the survey. Overall, about two-thirds of all herds in NSW showed evidence of infection, but the seroprevalence of N. caninum in individual beef cattle in NSW was low to moderate (1.8-11.3%). Significant differences occurred between regions. The risk for herds being positive for N. caninum was associated with geographic factors, particularly in the Mid-North Coast Region. © 2017 State of New South Wales.

  19. Herd-level seroprevalence of Neospora caninum infection in dairy cattle in central and northeastern Poland.

    Science.gov (United States)

    Kowalczyk, Sławomir J; Czopowicz, Michał; Weber, Corinna N; Müller, Elisabeth; Witkowski, Lucjan; Kaba, Jarosław

    2016-01-01

    A serosurvey was carried out to estimate the herd-level seroprevalence of Neospora caninum infection in cattle in central and northeastern Poland. Ninety seven dairy cattle herds from 2 provinces of Poland (Podlaskie, 47 herds and Łodzkie, 50 herds) were randomly enrolled in the study using two-stage cluster method. A simple random selection was applied within each herd to select a sample of adult cows (≥18 month-old). A total number of 734 cows were enrolled in the study. The animals were screened with a commercial competitive ELISA (Bio-X Diagnostics, Belgium). To calculate true herd-level seroprevalence test sensitivity and specificity were adjusted from an individual- to a herd-level using FreeCalc method. The true overall herd-level seroprevalence of N. caninum infection was 56.7% (95% CI: 47.5%, 65.9%). The true herd-level seroprevalence in Podlaskie was 63.3% (95% CI: 43.0%, 83.6%) and 50.5% (95% CI: 32.8%, 68.2%) in Łodzkie province and these figures did not differ significantly between the two provinces (chi2 test p = 0.238). One hundred forty three of 734 cows (19.5%) were seropositive which gave the true overall individual-level seroprevalence of 20.1% (95% CI: 17.4%, 23.2%). Percentage of seropositive cows in each herd varied from 6% to 80%. This study is the first epidemiological investigation of herd-level seroprevalence of N. caninum infection in Polish dairy cattle population. In conclusion, the result of the study confirmed previous data that N. caninum infection is widespread in the Polish cattle population and thus should be considered as a potential cause of spontaneous abortions.

  20. Anxiety reporting and culturally associated interpretation biases and cognitive schemas: a comparison of Mexican, Mexican American, and European American families.

    Science.gov (United States)

    Varela, R Enrique; Vernberg, Eric M; Sanchez-Sosa, Juan Jose; Riveros, Angelica; Mitchell, Montserrat; Mashunkashey, Joanna

    2004-06-01

    This study examined whether Mexican (n = 53), Mexican American (n = 50), and European American (n = 51) children differed in their reporting of anxiety symptoms and whether parental influence and specific cognitive schemas associated with Mexican culture were related to differences in anxiety reporting. As expected, Mexican and Mexican American children reported significantly more physiological and worry symptoms than the European American children. Mexican and Mexican American children endorsed collectivism as a cultural value more strongly than European American children, and the Mexican children evidenced greatest use of social strategies reflecting simpatia. In family discussions of ambiguous, potentially anxiety-arousing situations, Mexican and Mexican American parents verbalized a greater percentage of somatic interpretations than the European American parents. Results indicate potential linkages between cultural values, socialization practices, and anxiety reporting.

  1. Signal amplification in an agent-based herding model

    CERN Document Server

    Carro, Adrián; Miguel, Maxi San

    2013-01-01

    A growing part of the behavioral finance literature has addressed some of the stylized facts of financial time series as macroscopic patterns emerging from herding interactions among groups of agents with heterogeneous trading strategies and a limited rationality. We extend a stochastic herding formalism introduced for the modeling of decision making among financial agents, in order to take also into account an external influence. In particular, we study the amplification of an external signal imposed upon the agents by a mechanism of resonance. This signal can be interpreted as an advertising or a public perception in favor or against one of the two possible trading behaviors, thus periodically breaking the symmetry of the system and acting as a continuously varying exogenous shock. The conditions for the ensemble of agents to more accurately follow the periodicity of the signal are studied, finding a maximum in the response of the system for a given range of values of both the noise and the frequency of the...

  2. [Staphylococcus aureus variety hominis in a cattle herd].

    Science.gov (United States)

    Hummel, R; Meene, G

    1979-01-01

    A site-linked hominis variety of Staphylococcus aureus was isolated from a cattle herd. The find coincided with accumulated occurrence of clinical mastitis in cows and the affliction of one milker with a nose furuncle. The origin of the strain was not elucidated. The same strain had been isolated throughout three years of observation from clinical and subclinical mastitis as well as from chronic udder affection of cows, but no extraordinary accumulation of clinically manifest mastitis had been observed. The hominis site variety was quite rare among Staphylococcus aureus strains isolated from other cow herds. Enterotoxin formation was recorded from strains of the hominis site variety and from strains which could not be coordinated with any other of the known site varieties and fell under crystal-violet Type A. No enterotoxin formation was recordable from the strains of the bovis variety. The same applied to the group of staphylococci of crystal-violet Type C which could not be coordinated either with any known site variety and which is assumed to have originated from the hominis site variety. The above findings do not support any conclusion as to whether the cows had been infected by the milker or vice versa.

  3. Simulated Annealing-Based Krill Herd Algorithm for Global Optimization

    Directory of Open Access Journals (Sweden)

    Gai-Ge Wang

    2013-01-01

    Full Text Available Recently, Gandomi and Alavi proposed a novel swarm intelligent method, called krill herd (KH, for global optimization. To enhance the performance of the KH method, in this paper, a new improved meta-heuristic simulated annealing-based krill herd (SKH method is proposed for optimization tasks. A new krill selecting (KS operator is used to refine krill behavior when updating krill’s position so as to enhance its reliability and robustness dealing with optimization problems. The introduced KS operator involves greedy strategy and accepting few not-so-good solutions with a low probability originally used in simulated annealing (SA. In addition, a kind of elitism scheme is used to save the best individuals in the population in the process of the krill updating. The merits of these improvements are verified by fourteen standard benchmarking functions and experimental results show that, in most cases, the performance of this improved meta-heuristic SKH method is superior to, or at least highly competitive with, the standard KH and other optimization methods.

  4. Mexican national pyronometer network calibration

    Science.gov (United States)

    VAldes, M.; Villarreal, L.; Estevez, H.; Riveros, D.

    2013-12-01

    In order to take advantage of the solar radiation as an alternate energy source it is necessary to evaluate the spatial and temporal availability. The Mexican National Meterological Service (SMN) has a network with 136 meteorological stations, each coupled with a pyronometer for measuring the global solar radiation. Some of these stations had not been calibrated in several years. The Mexican Department of Energy (SENER) in order to count on a reliable evaluation of the solar resource funded this project to calibrate the SMN pyrometer network and validate the data. The calibration of the 136 pyronometers by the intercomparison method recommended by the World Meterological Organization (WMO) requires lengthy observations and specific environmental conditions such as clear skies and a stable atmosphere, circumstances that determine the site and season of the calibration. The Solar Radiation Section of the Instituto de Geofísica of the Universidad Nacional Autónoma de México is a Regional Center of the WMO and is certified to carry out the calibration procedures and emit certificates. We are responsible for the recalibration of the pyronometer network of the SMN. A continuous emission solar simulator with exposed areas with 30cm diameters was acquired to reduce the calibration time and not depend on atmospheric conditions. We present the results of the calibration of 10 thermopile pyronometers and one photovoltaic cell by the intercomparison method with more than 10000 observations each and those obtained with the solar simulator.

  5. EVALUATION OF AN O-ANTIGEN ELISA FOR SCREENING CATTLE HERDS FOR SALMONELLA-TYPHIMURIUM

    DEFF Research Database (Denmark)

    Hoorfar, Jeffrey; Bitsch, V.

    1995-01-01

    A total of 2585 serum samples from 62 dairy herds located in four different regions of Denmark were tested in an O-antigen (0:1,4,5,12)-based ELISA for the detection of antibodies against Salmonella typhimurium. Ten closed herds from an island with no reported occurrence of salmonellosis for seve......A total of 2585 serum samples from 62 dairy herds located in four different regions of Denmark were tested in an O-antigen (0:1,4,5,12)-based ELISA for the detection of antibodies against Salmonella typhimurium. Ten closed herds from an island with no reported occurrence of salmonellosis...... the salmonellosis-free island were ELISA-negative, and all but one of the 12 S typhimurium-infected herds were ELISA-positive, which resulted in a herd test sensitivity of 0.92 and herd test specificity of 1.0. Eleven of the 12 S typhimurium-infected herds were negative in a blocking ELISA based on a monoclonal...

  6. The use of a cluster analysis in across herd genetic evaluation for ...

    African Journals Online (AJOL)

    uovs

    Department of Animal, Wildlife and Grassland Sciences, UFS, PO Box 339, ... management level in a herd), herd size and average temperature and rainfall. ... the Bonsmara and Dorper, exist in countries such as Brazil, Argentina and Australia. ... Bonsmara dataset into different smaller sets, according to meteorological and ...

  7. Milk quality assurance programmes for paratuberculosis: stochastic simulation of within-herd infection dynamics and economics

    NARCIS (Netherlands)

    Weber, M.F.; Roermund, van H.J.W.; Velthuis, A.G.J.; Koeijer, de A.A.; Jong, de M.C.M.; Nielen, M.W.F.

    2005-01-01

    A bulk milk quality assurance programme for Mycobacterium avium subsp. paratuberculosis (Map) in dairy herds was simulated. Herds were certified as `low-Map bulk milk¿ if, with a certain probability, the concentration of Map in bulk milk did not exceed a maximum acceptable concentration (MAC). The M

  8. Paratuberculosis sero-status and milk production, SCC and calving interval in Irish dairy herds

    NARCIS (Netherlands)

    Hoogendam, K.; Richardson, E.; Mee, J.F.

    2009-01-01

    The objective of this study was to investigate the impact of paratuberculosis sero-status on milk yield, fat, protein, somatic cell count and calving interval in Irish dairy herds. Serum from all animals over 12 months of age (n=2,602) in 34 dairy herds was tested for antibodies to Mycobacterium avi

  9. A case-control study of risk factors for bovine cysticercosis in Danish cattle herds

    DEFF Research Database (Denmark)

    Calvo Artavia, Francisco Fernando; Nielsen, Liza Rosenbaum; Dahl, J.;

    2013-01-01

    a questionnaire and register data from the Danish Cattle Database were grouped into meaningful variables and used to investigate the risk factors for BC using a multivariable logistic regression model. Case herds were almost three times more likely than control herds to let all or most animals out grazing. Case...

  10. Veterinarian awareness of farmer goals and attitudes to herd health management in The Netherlands

    NARCIS (Netherlands)

    Derks, M.; Woudenbergh, van B.; Boender, M.; Kremer, W.; Werven, van T.; Hogeveen, H.

    2013-01-01

    In providing advice on herd health, veterinarians need to be aware of farmers' goals and priorities. To determine the level of awareness, 29 veterinarians from 15 practices completed questionnaires during visits to dairy farms within the scope of veterinary herd health management (VHHM) programmes.

  11. A longitudinal study of serological patterns of respiratory infections in nine infected Danish swine herds

    DEFF Research Database (Denmark)

    Andreasen, Margit; Nielsen, Jens; Bækbo, Poul

    2000-01-01

    Sixteen litters of seven pigs from each of nine Danish farrow-to-finish herds were followed to investigate the serological patterns caused by natural infection with Mycoplasma hyponeumoniae, Pasteurella multocida toxin and Actinobacillus pleuroneumoniae serotypes 2, 5-7, 12. In seven of the herds...

  12. An object-oriented Bayesian network modeling the causes of leg disorders in finisher herds

    DEFF Research Database (Denmark)

    Jensen, Tina Birk; Kristensen, Anders Ringgaard; Toft, Niels

    2009-01-01

    The implementation of an effective control strategy against disease in a finisher herd requires knowledge regarding the disease level in the herd. A Bayesian network was constructed that can estimate risk indexes for three cause-categories of leg disorders in a finisher herd. The cause-categories......The implementation of an effective control strategy against disease in a finisher herd requires knowledge regarding the disease level in the herd. A Bayesian network was constructed that can estimate risk indexes for three cause-categories of leg disorders in a finisher herd. The cause...... pigs (e.g. results from diagnostic tests) were used to estimate the most likely cause of leg disorders at herd level. As information to the model originated from two different levels, we used an object-oriented structure in order to ease the specification of the Bayesian network. Hence, a Herd class...... and a Pig class comprised the basic components of the object-oriented structure. The causal structure of the model was based on evidence from published literature. The conditional probabilities used in the model were elicited from experts within the field and from the published literature. To illustrate...

  13. Control of bovine leukosis virus in a dairy herd by a change in dehorning.

    OpenAIRE

    DiGiacomo, R F; Hopkins, S G; Darlington, R L; Evermann, J F

    1987-01-01

    Following the demonstration that bovine leukosis virus was transmitted in calves by gouge dehorning, electrical dehorning at a younger age was implemented in a commercial Holstein herd. Subsequently, annual testing of the herd revealed a decline in the prevalence of bovine leukosis virus antibodies as older cattle dehorned by the former method were replaced by younger cattle dehorned by the latter method.

  14. Management information system impact on dairy production for selected herds in Texas

    NARCIS (Netherlands)

    Tomaszewski, M.A.; Dijkhuizen, A.A.; Huirne, R.B.M.; Otten, A.

    2000-01-01

    Yearly production and performance data were obtained for dairy herd improvement members in Texas to determine whether on-farm use of a management information system (MIS) quantitatively impacted performance. Data from 66 dairy operations for the years 1983–1996 were evaluated. Herds enrolled in an M

  15. The effect of grazing on cow mortality in Danish dairy herds

    DEFF Research Database (Denmark)

    Burow, Elke; Thomsen, Peter Thorup; Sørensen, Jan Tind;

    2011-01-01

    The effect of summer grazing in large Danish dairy herds and certain management characteristics of grazing were studied for their impact on dairy cow mortality. Mortality data (from the Danish Cattle Database) from 391 Danish dairy herds (>100 cows) were combined with information from a questionn...

  16. Characteristics of the USA dairy herd as related to management and demographic elements

    Science.gov (United States)

    The data characteristics of the United States dairy herd related to animals enrolled in milk recording (dairy herd improvement) are the basic foundation and important influencers for the management and genetic progress achieved in a population or animal production unit. The amount, characteristics ...

  17. Metabolic parameters and blood leukocyte profiles in cows from herds with high or low mastitis incidence.

    Science.gov (United States)

    Holtenius, K; Persson Waller, K; Essén-Gustavsson, B; Holtenius, P; Hallén Sandgren, C

    2004-07-01

    The objective of this study was to determine whether there were differences in metabolic parameters and blood leukocyte profiles between cows in herds with high or low yearly mastitis incidence. In this study, 271 cows from 20 high yielding dairy herds were examined. According to the selection criteria, all herds had low somatic cell counts. Ten of the selected herds represented low mastitis treatment incidence (LMI) and ten herds had high mastitis treatment incidence (HMI). The farms were visited once and blood samples were taken from each cow that was in the interval from three weeks before to 15 weeks after parturition. The eosinophil count was significantly lower among cows from the HMI herds in the period from four weeks to 15 weeks after parturition. The plasma concentrations of beta-hydroxybutyrate, glucose, insulin and urea did not differ between groups, but the concentration of nonesterified fatty acids was significantly higher among HMI cows during the period three weeks after parturition. The concentration of the amino acid tryptophan in plasma was significantly lower among the HMI cows prior to parturition. Glutamine was significantly lower in cows from HMI herds during the first three weeks after parturition. Arginine was consistently lower in HMI cows, although the decrease was only significant during the period from four to fifteen weeks after parturition. The results suggest that there were differences in the metabolism and immune status between herds with high or low yearly mastitis treatment incidence indicating an increased metabolic stress in HMI cows.

  18. Risk factors and epidemiological characteristics of new neonatal porcine diarrhoea syndrome in four Danish herds

    DEFF Research Database (Denmark)

    Kongsted, Hanne; Toft, Nils; Nielsen, Jens Peter

    2014-01-01

    -65%) of piglets born by mature sows. In total of 26% of piglets had liquid faeces on the day of birth. Approximately half of these piglets developed NNPDS. In the majority of cases (50-70% of cases within herds) symptoms started on the second or third day of life. Piglets in Herd 1 had 12.8 times higher...

  19. Evaluating the effects of nutrition, disease, and predation on calf recruitment in the northern Alaska Peninsula Caribou herd

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Northern Alaska Peninsula Caribou Herd is an important subsistence and recreational hunting resource in the southwest Alaska region. This herd has declined by...

  20. Heterosis and direct effects for Charolais-sired calf weight and growth, cow weight and weight change, and ratios of cow and calf weights and weight changes across warm season lactation in Romosinuano, Angus, and F cows in Arkansas.

    Science.gov (United States)

    Riley, D G; Burke, J M; Chase, C C; Coleman, S W

    2016-01-01

    The use of Brahman in cow-calf production offers some adaptation to the harsh characteristics of endophyte-infected tall fescue. Criollo breeds, such as the Romosinuano, may have similar adaptation. The objectives were to estimate genetic effects in Romosinuano, Angus, and crossbred cows for their weights, weights of their calves, and ratios (calf weight:cow weight and cow weight change:calf weight gain) across lactation and to assess the influence of forage on traits and estimates. Cows ( = 91) were bred to Charolais bulls after their second parity. Calves ( = 214) were born from 2006 to 2009. Cows and calves were weighed in early (April and June), mid- (July), and late lactation (August and October). Animal was a random effect in analyses of calf data; sire was random in analyses of cow records and ratios. Fixed effects investigated included calf age, calf sex, cow age-year combinations, sire breed of cow, dam breed of cow, and interactions. Subsequent analyses evaluated the effect of forage grazed: endophyte-free or endophyte-infected tall fescue. Estimates of maternal heterosis for calf weight ranged from 9.3 ± 4.3 to 15.4 ± 5.7 kg from mid-lactation through weaning ( Angus cows and lower ( Angus cows had the lowest ( < 0.05) ratios (negative) of cow weight change:calf weight gain, indicating an energy-deficit condition. Cows grazing endophyte-free tall fescue had more negative ( < 0.05) values for this trait but not in early lactation ( < 0.05). Estimates of heterosis ranged from 12.8 ± 9.5 to 28.6 ± 9.4 kg for cow weight, 7.9 ± 3.0 to 15.8 ± 5.0 kg for cow weight change, and 0.07 ± 0.03 to 0.27 ± 0.1 for cow weight change:calf weight gain. Direct Romosinuano effects ranged from 14.8 ± 4.2 to 49.8 ± 7.7 kg for cow weight change and 0.2 ± 0.04 to 0.51 ± 0.14 for cow weight change:calf weight gain. The adaptive ability of Romosinuano in temperate fescue regions may be favorable with respect to relative cow and calf weight but may be a consequence of

  1. Premilking teat disinfection: is it worthwhile in pasture-grazed dairy herds?

    Science.gov (United States)

    Morton, John M; Penry, John F; Malmo, Jakob; Mein, Graeme A

    2014-12-01

    A controlled trial was conducted in 5 pasture-grazed commercial dairy herds in Australia in 2012 to determine whether premilking teat disinfection and drying of teats reduces clinical mastitis incidence during early lactation by at least 50%. A 50% reduction was estimated to be the minimum required to justify additional costs of labor, disinfectants, and other resources if premilking teat disinfection was implemented in a 500-cow herd averaging 8 clinical cases per 100 cow-months. A secondary aim was to determine whether this premilking teat disinfection routine reduces incidence of new udder infections. Treatment was applied in each herd for approximately 60 d (range of 59.5 to 61 d), commencing in each herd soon after the start of the herd's main or only calving period. Within each herd, cows were allocated to either the treatment (premilking disinfection) or the control (no premilking disinfection) group based on their herd identity number. During the trial period, any cow having a new case of clinical mastitis or an individual cow cell count greater than 250,000 cells/mL of milk (when preceded by individual cow cell counts of 250,000 cells/mL of milk or below) was deemed to have had a new infection. Overall, neither clinical mastitis incidence nor new infection rate differed significantly between treatment and control groups. Over the whole study period, 98 of the 1,029 cows in the premilking disinfection group and 97 of the 1,025 cows in the control group had clinical mastitis. Total cow-days at risk of clinical mastitis were similar in each group. However, clinical incidence rates were markedly lower in treatment cows in one herd (herd 3; incidence rate ratio=0.34) and there was some evidence that new infection incidence rates were lower in treated cows in this herd (incidence rate ratio=0.42). Rainfall during the study period was below long-term district average in all 5 study herds. Cows' teats were less dirty than in previous, wetter years for the 4 herds

  2. Food Acculturation Drives Dietary Differences among Mexicans, Mexican Americans, and Non-Hispanic Whites123

    OpenAIRE

    2011-01-01

    Our aim was to examine the effects of food acculturation on Mexican Americans’ (MA) diets, taking the Mexican diet as reference. We used nationally representative samples of children (2–11 y) and female adolescents and adults (12–49 y) from the Mexican National Nutrition Survey 1999 and NHANES 1999–2006 to compare the diets of Mexicans (n = 5678), MA born in Mexico (MAMX) (n = 1488), MA born in the United States (MAUS) (n = 3654), and non-Hispanic white Americans (NH-White) (n = 5473). One 24...

  3. Economic evaluation of vaccination programs: the impact of herd-immunity.

    Science.gov (United States)

    Brisson, M; Edmunds, W J

    2003-01-01

    The unique characteristic of vaccination is that it not only reduces the incidence of disease in those immunized but also indirectly protects nonvaccinated susceptibles against infection (produces herd-immunity). The bulk of economic evaluations of vaccination programs continue to use models that cannot take into account the indirect effects produced by herd-immunity. Here, the authors illustrate the importance of incorporating herd-immunity externalities when assessing the cost-effectiveness of vaccination progams. To do this, they compare 2 methods of estimating the benefits of routine mass vaccination: one that includes herd-immunity (dynamic approach) and one that does not (static approach). Finally, they use the results to clarify a number of misconceptions that are common in the literature concerning herd-immunity and dynamical effects produced by models.

  4. Evaluation of the surveillance program of Streptococcus agalactiae in Danish dairy herds

    DEFF Research Database (Denmark)

    Andersen, H. J.; Pedersen, L. H.; Aarestrup, Frank Møller;

    2003-01-01

    The aim of this study was to evaluate the Danish surveillance program of Streptococcus agalactiae in dairy herds with respect to 1) fluctuation over time of the presence of S. agalactiae in bulk tank milk, 2) sensitivity and specificity of the bacteriological method used, and 3) contamination...... of bulk tank milk samples with milk from other herds. From June to September 1996, bulk tank milk was sampled from 100 Danish dairy herds seven times, with intervals of 2 wk. The samples were examined for the presence of S. agalactiae by four different methods: 1) by the method approved for the program, 2...... the isolates. Streptococcus agalactiae was found in eight of 96 herds in which S. agalactiae had never previously been found during the surveillance program. Streptococcus agalactiae was not found in all seven sampling rounds in any of the eight herds. Comparing the approved method with supplemental findings...

  5. A diagnostic and prognostic tool for epidemiologic and economic analyses of dairy herd health management

    DEFF Research Database (Denmark)

    Enevoldsen, Carsten; Sørensen, J.T.; Thysen, Iver;

    1995-01-01

    A computer program framework was established to enable a dairy herd production consultant to perform whole-herd analysis. The diagnostic process was an extensive data analysis 1) to derive key parameters related to production, reproduction, and health and 2) to produce input to a prognostic process....... The prognostic process synthesized the obtained information into short- or long-term prognoses for the herd through a complex herd simulation model. Site specificity of parameter estimation and forecasting and explorability of assumptions and results were major characteristics of the approach. A user acceptance...... problem related to the simulation was addressed through a simultaneous process of development and validation during the introduction of the program framework into veterinary practices. The generally slow adoption of herd simulation models in extension work could be due to lack of credibility of the models...

  6. Risk factors for changing test classification in the Danish surveillance program for Salmonella in dairy herds

    DEFF Research Database (Denmark)

    Nielsen, Lennarth Ravn; Warnick, L. D.; Greiner, M.

    2007-01-01

    A surveillance program in which all cattle herds in Denmark are classified into Salmonella infection categories has been in place since 2002. Dairy herds were considered test negative and thus most likely free of infection if Salmonella antibody measurements were consistently low in bulk tank milk...... samples collected every 3 mo. Herds were considered test positive and thus most likely infected if the 4-quarter moving average bulk tank milk antibody concentration was high or if there was a large increase in the most recent measurement compared with the average value from the previous 3 samples....... The objective of this study was to evaluate risk factors for changing from test negative to positive, which was indicative of herds becoming infected from one quarter of the year to the next, and risk factors for changing from test positive to negative, which was indicative of herds recovering from infection...

  7. A diagnostic and prognostic tool for epidemiologic and economic analyses of dairy herd health management

    DEFF Research Database (Denmark)

    Enevoldsen, Carsten; Sørensen, J.T.; Thysen, Iver

    1995-01-01

    A computer program framework was established to enable a dairy herd production consultant to perform whole-herd analysis. The diagnostic process was an extensive data analysis 1) to derive key parameters related to production, reproduction, and health and 2) to produce input to a prognostic process....... The prognostic process synthesized the obtained information into short- or long-term prognoses for the herd through a complex herd simulation model. Site specificity of parameter estimation and forecasting and explorability of assumptions and results were major characteristics of the approach. A user acceptance...... problem related to the simulation was addressed through a simultaneous process of development and validation during the introduction of the program framework into veterinary practices. The generally slow adoption of herd simulation models in extension work could be due to lack of credibility of the models...

  8. Effect of herd cues and product involvement on bidder online choices.

    Science.gov (United States)

    Chen, Yi-Fen; Wang, Ya-Ju

    2010-08-01

    Previous works have shown that consumers are influenced by others in decision making. Herd behavior is common in situations in which consumers infer product quality from other consumer choices and incorporate that information into their own decision making. This research presents two studies examining herd effect and the moderating role of product involvement on bidder choices in online auctions. The two studies addressed the influence on bidder online choices of herd cues frequently found in online auctions, including feedback ratings and number of questions and answers. The experimental results demonstrated that bidders use online herd cues when making decisions in online auctions. Additionally, the effects of herd cues on bidder online choices were stronger in high-involvement than low-involvement participants. Results and implications are discussed.

  9. Molecular epidemiology and strain-specific characteristics of Streptococcus agalactiae at the herd and cow level.

    Science.gov (United States)

    Mahmmod, Y S; Klaas, I C; Katholm, J; Lutton, M; Zadoks, R N

    2015-10-01

    Host-adaptation of Streptococcus agalactiae subpopulations has been described whereby strains that are commonly associated with asymptomatic carriage or disease in people differ phenotypically and genotypically from those causing mastitis in dairy cattle. Based on multilocus sequence typing (MLST), the most common strains in dairy herds in Denmark belong to sequence types (ST) that are also frequently found in people. The aim of this study was to describe epidemiological and diagnostic characteristics of such strains in relation to bovine mastitis. Among 1,199 cattle from 6 herds, cow-level prevalence of S. agalactiae was estimated to be 27.4% based on PCR and 7.8% based on bacteriological culture. Quarter-level prevalence was estimated at 2.8% based on bacteriological culture. Per herd, between 2 and 26 isolates were characterized by pulsed-field gel electrophoresis (PFGE) and MLST. Within each herd, a single PFGE type and ST predominated, consistent with a contagious mode of transmission or point source infection within herds. Evidence of within-herd evolution of S. agalactiae was detected with both typing methods, although ST belonged to a single clonal complex (CC) per herd. Detection of CC23 (3 herds) was associated with significantly lower approximate count (colony-forming units) at the quarter level and significantly lower cycle threshold value at the cow level than detection of CC1 (2 herds) or CC19 (1 herd), indicating a lower bacterial load in CC23 infections. Median values for the number of infected quarters and somatic cell count (SCC) were numerically but not significantly lower for cows infected with CC23 than for cows with CC1 or CC19. For all CC, an SCC threshold of 200,000 cells/mL was an unreliable indicator of infection status, and prescreening of animals based on SCC as part of S. agalactiae detection and eradication campaigns should be discouraged.

  10. Evaluation of the establishment of herd immunity in the population by means of serological surveys and vaccination coverage.

    Science.gov (United States)

    Plans-Rubió, Pedro

    2012-02-01

    The necessary herd immunity blocking the transmission of an infectious agent in the population is established when the prevalence of protected individuals is higher than a critical value, called the herd immunity threshold. The establishment of herd immunity in the population can be determined using the vaccination coverage and seroepidemiological surveys. The vaccination coverage associated with herd immunity (V(c)) can be determined from the herd immunity threshold and vaccine effectiveness. This method requires a vaccine-specific effectiveness evaluation, and it can be used only for the herd immunity assessment of vaccinated communities in which the infectious agent is not circulating. The prevalence of positive serological results associated with herd immunity can be determined from the herd immunity threshold, in terms of prevalence of antibodies (p(c)) and serological test performance. The herd immunity is established when the prevalence of antibodies is higher than pc. This method can be used to assess the establishment of herd immunity in different population groups, both when the infectious agent is circulating and when it is not possible to assess vaccine effectiveness. The herd immunity assessment in Catalonia, Spain, showed that the additional vaccination coverage required to establish herd immunity was 3-6% for measles, mump and varicella and 11% poliovirus type III in school children, 17-59% for diphtheria in youth and adults and 25-46% for persussis in school children, youth and adults.

  11. Prevalence and molecular characteristics of Methicillin-Resistant Staphylococcus aureus (MRSA) in organic pig herds in The Netherlands

    NARCIS (Netherlands)

    Bondt, N.; Vijver, van de L.P.L.; Tulinski, P.; Mevius, D.; Verwer, C.

    2014-01-01

    The prevalence of the methicillin-resistant Staphylococcus aureus (MRSA) among conventional pig herds in the Netherlands is high (around 71%). Nevertheless, information about the prevalence of MRSA among organic pig herds is lacking. Here, we report a study on 24 of the 49 organic pig herds in the N

  12. Transmission of bovine herpesvirus 1 within and between herds on an island with a BHV1 control programme

    NARCIS (Netherlands)

    Hage, J.J.; Schukken, Y.H.; Schols, H.; Maris-Veldhuis, M.A.; Rijsewijk, F.A.M.; Klaassen, C.H.L.

    2003-01-01

    Transmission of bovine herpesvirus 1 (BHV1) within and between herds was studied on the island of Ameland, The Netherlands. There were 50 herds with 3300 head of cattle on the island. Herds were divided into three groups: (1) only containing seronegative cattle, (2) containing seronegative cattle an

  13. A longitudinal study of Salmonella enterica infections in high- and low-seroprevalence finishing swine herds in the Netherlands

    DEFF Research Database (Denmark)

    van der Wolf, P.J.; Wong, Danilo Lo Fo; Wolbers, W.B.

    2001-01-01

    The purpose of this investigation was to study the incidence and course of Salmonella infections in finishing pig herds in order to asses the stability of a given Salmonella herd status. Five low- and 7 high-seroprevalence herds were followed for seven sampling rounds. Each round, blood and faecal...

  14. Dynamic probabilistic simulation of dairy herd management practices 1. Model description and outcome of different seasonal calving patterns.

    NARCIS (Netherlands)

    Jalvingh, A.W.; Arendonk, van J.A.M.; Dijkhuizen, A.A.

    1993-01-01

    A dynamic probabilistic model has been designed to determine the technical and economic consequences of various biological variables and management strategies concerning reproduction, replacement and calving patterns in dairy herds. The Markov chain approach is used to simulate herd dynamics. Herds

  15. Suggested revision for west mexican archeological sequences.

    Science.gov (United States)

    Long, S V; Taylor, R E

    1966-12-16

    A review of the radiocarbon dates and published and unpublished archeological data from the West Mexican states of Sinaloa, Nayarit, Jalisco, and Colima has resulted in a revised tentative chronology for West Mexico.

  16. Mexican Fan Palm - Orange Co. [ds350

    Data.gov (United States)

    California Department of Resources — This dataset provides the known distribution of Mexican fan palm (Washingtonia robusta) in southern Orange County. The surveys were conducted from May to June, 2007...

  17. Mexican Mid-winter Waterfowl Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Mexican Mid-winter Waterfowl Survey is a continuation of the annual winter waterfowl survey which is conducted in the United States and Mexico. Since the...

  18. Narcocultura: a threat to Mexican national security?

    OpenAIRE

    Fugate, Ashleigh A.

    2012-01-01

    Approved for public release; distribution is unlimited. This project analyzes the collective identity and narratives surrounding the culture of the drug trafficking organizations (DTOs), or narcocultura, in Mexico. It questions whether the visible cultural artifacts of the DTOs reflect a cultural identity or if they create an identity that threatens Mexican national security. The analysis establishes that narcocultura is a relevant framework to study Mexican transnational organized crime (...

  19. Narcocultura: a threat to Mexican national security?

    OpenAIRE

    Fugate, Ashleigh A.

    2012-01-01

    Approved for public release; distribution is unlimited. This project analyzes the collective identity and narratives surrounding the culture of the drug trafficking organizations (DTOs), or narcocultura, in Mexico. It questions whether the visible cultural artifacts of the DTOs reflect a cultural identity or if they create an identity that threatens Mexican national security. The analysis establishes that narcocultura is a relevant framework to study Mexican transnational organized crime (...

  20. Epianthropochory in Mexican weed communities.

    Science.gov (United States)

    Vibrans, H

    1999-04-01

    The diaspores of the 50 most important maize field weed species (agrestals) in a traditional maize-growing area of south-central Mexico (region of Puebla and Tlaxcala) were analyzed for morphological adaptations to long-distance dispersal. Adaptations to wind-dispersal were absent and to endozoochory were minimal. Most species had no visible adaptations and are presumably transported with mud. However, about one-quarter of the taxa, particularly the tall and dominant ones, relied at least partially on burrs with hooks or awns. The possible vectors for these exo- or epizoochorous species are discussed: the most likely regular dispersers are humans (epianthropochory). Interviews with farmers confirm this conclusion. Using humans as vectors allows the plant to transport relatively large seeds to favorable habitats (directed dispersal). The importance of this relatively rare dispersal adaptation in Mexican maize field weeds leads to questions on the origin and evolution of these agrestals.

  1. Mexican Virtual Solar Observatory project

    Science.gov (United States)

    Santillán, Alfredo J.; Hernández, Liliana; Salas, Guillermo; Sánchez, Antonio; González, Alejandro; Franco, José

    2007-08-01

    The Virtual Solar Observatory (VSO) concept outlines a software environment for searching, obtaining and analyzing data from archives of solar data that are distributed at many different observatories around the world (Hill 2006, in this volume). The VSO, however, not only provides fast and reliable access to the existing data of Solar Active Regions, but also represents a powerful and unique tool to perform numerical simulations of the evolution and present state of solar phenomena. Two centers at UNAM, the Institute of Astronomy (IA) and the Supercomputer Center (DGSCA), along with the Sonora University, are working together to create the Mexican Virtual Solar Observatory (MVSO) that will be part of a wider national effort.

  2. Estimating the number of undetected multi-resistant Salmonella Typhimurium DT104 infected pig herds in Denmark.

    Science.gov (United States)

    Rugbjerg, Helene; Wingstrand, Anne; Hald, Tine; Andersen, Jens Strodl; Lo Fo Wong, Danilo M A; Korsgaard, Helle

    2004-10-14

    In Denmark, the detection of multi-resistant Salmonella Typhimurium DT104 (MRDT104)-infected pig herds relies on the national Salmonella surveillance programme at the farm and slaughterhouse levels of production. With the surveillance sampling protocol and the diagnostic methods currently used, some herds might remain undetected. The number of undetected Danish pig herds infected with MRDT104 in the period 1 August 2001-31 July 2002 was estimated and compared with the number of culture-confirmed detected herds. A flow chart was constructed to illustrate where infected herds will go undetected in the surveillance system and Monte Carlo simulation was used to model the actual number of pig herds infected with MRDT1104. We estimated that 52 (90% CI [28, 178]) finisher herds were infected with MRDT104 compared to 23 (44%) detected. Among sow herds with production of weaners or growers, we estimated that 38 (90% CI [23, 74]) were infected with MRDT104 compared to 7 (18%) actually detected. Among breeder and multiplier herds, we estimated that five (90% CI [3, 8]) herds were infected with MRDT104 compared to three (60%) detected. In total, we estimated that 102 pig herds were infected with MRDT104 from 1 August 2001 till 31 July 2002 (90% CI [63, 228]). In comparison, 33 (32%) infected herds were detected in this period. The predicted proportion of undetected herds varied considerably with herd type. We infer that the proportion of detected MRDT104 infected herds depended on the intensity of the combined serological and bacteriological testing.

  3. Patterns of clinical mastitis manifestations in Danish organic dairy herds

    DEFF Research Database (Denmark)

    Vaarst, Mette; Enevoldsen, Carsten

    1997-01-01

    Danish organic dairy production is characterized by a low input of antibiotics for udder treatment and a high input of other mastitis control procedures. A study was conducted in 14 organic dairy herds with the objectives of obtaining a comprehensive description of clinical mastitis cases...... and identifying characteristic patterns in these results. Clinical signs, inflammatory reactions and microbiological identifications were obtained from 367 cases of clinical mastitis occurring over 18 months. Cow characteristics and preincident values such as milk yield and somatic cell count were obtained...... for each cow. Signs of previous udder inflammation were present in two-thirds of the clinical mastitis cases. Severe local inflammatory reactions were found in 21% of the cases and some indication of generalized signs such as fever and reduced appetite were found in 35% of the cases. Logistic regression...

  4. Multiple hereditary ocular anomalies in a herd of cattle.

    Science.gov (United States)

    Kaswan, R L; Collins, L G; Blue, J L; Martin, C L

    1987-07-01

    A Brahman x Santa Gertrudis herd of cows bred to a Hereford bull was evaluated because of a 3-year history of several calves born with congenital blindness. Multiple congenital ocular anomalies in 2 calves included microphthalmos, microcornea, microcoria, heterochromia iridis, microlentia, cataracts, retinal dysplasia, retinal detachment, anterior segment dysgenesis, acorea, and proliferation of the anterior neuroectoderm. On the basis of the lack of environmental factors and persistence of an intermittent problem when breeding to a single bull, a genetic defect was diagnosed as the probable cause. Dominant inheritance with varied expressivity may have best explained the lack of obvious signs in the bull, with emergence of various anterior and posterior segment defects in offspring from unrelated cows.

  5. Quickest Time Herding and Detection for Optimal Social Learning

    CERN Document Server

    Krishnamurthy, Vikram

    2010-01-01

    This paper considers social learning amongst rational agents (for example, sensors in a network). We consider three models of social learning in increasing order of sophistication. In the first model, based on its private observation of a noisy underlying state process, each agent selfishly optimizes its local utility and broadcasts its action. This protocol leads to a herding behavior where the agents eventually choose the same action irrespective of their observations. We then formulate a second more general model where each agent is benevolent and chooses its sensor-mode to optimize a social welfare function to facilitate social learning. Using lattice programming and stochastic orders, it is shown that the optimal decision each agent makes is characterized by a switching curve on the space of Bayesian distributions. We then present a third more general model where social learning takes place to achieve quickest time change detection. Both geometric and phase-type change time distributions are considered. ...

  6. Risk factors for intestinal pathogens in Danish finishing pig herds

    DEFF Research Database (Denmark)

    Stege, H.; Jensen, Tim Kåre; Møller, Kristian;

    2001-01-01

    The objective of this investigation was to identify risk factors for infection with the intestinal bacteria: Lawsonia intracellularis, Brachyspira hyodysenteriae, Serpulina intermedia, Brachyspira innocens, Brachyspira pilosicoli and swine-pathogenic Escherichia coli (serogroups O138, O139, O141......) or culture (all other agents). Information on feed and management procedures was collected by filling in questionnaires at the herd visits. The questionnaire, included information on 29 dichotomous variables and three continuous variables. Variables with P ...-test) were selected for the statistical modelling. Our conclusions, based on the results of multifactorial logistic regression (out-off: P = 0.05), were the following: 1. Consistent batch production was associated with reduced prevalences of L. intracellularis and weakly beta -haemolytic spirochetes (S...

  7. Solving the shepherding problem: heuristics for herding autonomous, interacting agents.

    Science.gov (United States)

    Strömbom, Daniel; Mann, Richard P; Wilson, Alan M; Hailes, Stephen; Morton, A Jennifer; Sumpter, David J T; King, Andrew J

    2014-11-06

    Herding of sheep by dogs is a powerful example of one individual causing many unwilling individuals to move in the same direction. Similar phenomena are central to crowd control, cleaning the environment and other engineering problems. Despite single dogs solving this 'shepherding problem' every day, it remains unknown which algorithm they employ or whether a general algorithm exists for shepherding. Here, we demonstrate such an algorithm, based on adaptive switching between collecting the agents when they are too dispersed and driving them once they are aggregated. Our algorithm reproduces key features of empirical data collected from sheep-dog interactions and suggests new ways in which robots can be designed to influence movements of living and artificial agents.

  8. Self-boosting vaccines and their implications for herd immunity.

    Science.gov (United States)

    Arinaminpathy, Nimalan; Lavine, Jennie S; Grenfell, Bryan T

    2012-12-01

    Advances in vaccine technology over the past two centuries have facilitated far-reaching impact in the control of many infections, and today's emerging vaccines could likewise open new opportunities in the control of several diseases. Here we consider the potential, population-level effects of a particular class of emerging vaccines that use specific viral vectors to establish long-term, intermittent antigen presentation within a vaccinated host: in essence, "self-boosting" vaccines. In particular, we use mathematical models to explore the potential role of such vaccines in situations where current immunization raises only relatively short-lived protection. Vaccination programs in such cases are generally limited in their ability to raise lasting herd immunity. Moreover, in certain cases mass vaccination can have the counterproductive effect of allowing an increase in severe disease, through reducing opportunities for immunity to be boosted through natural exposure to infection. Such dynamics have been proposed, for example, in relation to pertussis and varicella-zoster virus. In this context we show how self-boosting vaccines could open qualitatively new opportunities, for example by broadening the effective duration of herd immunity that can be achieved with currently used immunogens. At intermediate rates of self-boosting, these vaccines also alleviate the potential counterproductive effects of mass vaccination, through compensating for losses in natural boosting. Importantly, however, we also show how sufficiently high boosting rates may introduce a new regime of unintended consequences, wherein the unvaccinated bear an increased disease burden. Finally, we discuss important caveats and data needs arising from this work.

  9. [Safeguarding herds from the animal hygiene point of view].

    Science.gov (United States)

    Hartung, J

    2005-08-01

    One of the most important concepts for the protection of herd health is the implementation of structural and organisational measures to prevent infective agents and other adverse compounds from entering the farm. Safeguarding health, well-being and production efficiency is part of the overall management concept of hygiene in animal production systems. This paper presents an overview of the most important rules and recommendations to protect livestock production facilities from the intrusion of infectious pathogens, beginning with the right choice of the site for the farm and the animal housing ("safe distances" to neighbouring farm animal houses), solid fencing and control and disinfecting places at the entrance gate. The traffic of vehicles and people transporting animals, feedstuff, equipment and slurry or manure to and from the facility should be reduced to a minimum. Fallen animals should be stored in separate and safe containers until removed by specialised companies. Regular control of rodents, insects and wild birds is crucial to avoid the transfer of infectious agents from farm to farm and between herds within a farm. Equally important factors are the health status of personnel to avoid transmission of zoonotic diseases, the application of the all-in-all-out system and a strict cleaning and disinfecting regime. The internal and external organisational measures for preventing the spread of infections in animal production will gain increasing importance in the future because the farm animal producer bears the responsibility for the production of safe and healthy food at the primary segment of the food chain. Increasing restrictions on the use of veterinary drugs for food delivering animals will increase the importance of prophylaxis, prevention and protection of production units as the keys for safeguarding health, well-being and efficiency of farm animals. Only the application of strict hygiene principles in animal production will make it possible to meet

  10. Mortality pattern of Murrah buffalo males in an organised herd

    Directory of Open Access Journals (Sweden)

    Pushp Raj Shivahre

    2014-05-01

    Full Text Available Aim: The present study was carried out to analyze mortality pattern in Murrah buffalo males in National Dairy Research Institute herd. Materials and Methods: Records of 1029 Murrah buffalo males born during the period 1997-2012, at NDRI, Karnal, were analyzed to study mortality pattern in different age groups. The percent of animal disposed from the herd due to different reasons was calculated by proportion using descriptive statistics. Results: The overall percent mortality in 0-1m, 1-2m, 2-3m, 3-6m, 6-18m, 18m-3 yr and >3 year age groups were 17.49, 5.99, 3.34, 5.42, 6.35, 2.59 and 3.93, respectively. The main cause of mortality in 0-1, 1-2, 2-3 and 6-18 m of age groups was respiratory problems (6.61%, 1.79%, 1.06% and 1.97% respectively. Main causes of mortality in age group 3-6 months were general debility (1.57% followed by respiratory and digestive problems (1.22%, miscellaneous (0.87%, liver and urinary problems (0.17%. Mortality could not reveal any consistent trend across different seasons and period of birth. General debility (1.29% followed by toxemia, liver problems and miscellaneous reasons were main causes of mortality in age group 18 m – 3 yr of age. In males above three years of age, general debility (2.81% followed by respiratory problems (1.12% were the main causes of mortality. Conclusion: Intensive health care and management is required for young male buffalo calves especially in hot humid months of rainy season and cold inclement weather conditions in winter months to minimize mortality due to respiratory and digestive problems.

  11. Piglet preweaning mortality in a commercial swine herd in Thailand.

    Science.gov (United States)

    Nuntapaitoon, Morakot; Tummaruk, Padet

    2015-12-01

    In the modern swine industry, the number of piglets born alive per litter is dramatically increasing due to genetic improvement of litter traits. However, knowledge on post-partum management is inadequate to reduce piglet preweaning mortality. The present study aimed to investigate piglet preweaning mortality in a commercial swine herd in Thailand in relation to the number of littermate pigs and piglet birth weight. Data included 11,154 litters from 3574 sows farrowed from January 2009 to December 2012. Littermate pig was defined as the number of piglets after cross-fostering. Number of littermate pigs was classified as 1-7, 8-10, 11-12, and 13-15 piglets per litter. Mean birth weight of the piglets was classified as low (Piglet preweaning mortality was calculated, logged transformed, and analyzed by general linear mixed models. On average, piglet preweaning mortality was 14.5 % (median = 10.0 %). Piglet preweaning mortality in the litter with 13-15 littermate pigs (24.1 %) was significantly higher than the litter with 1-7 (11.9 %, P piglet birth weight had a higher piglet preweaning mortality rate (18.8 %) than the litters with a medium (15.7 %, P piglet birth weight (12.1 %, P piglet preweaning mortality in commercial swine herds, special care needs to be taken in litters with more than 13 littermate pigs and with piglets with birth weight below 1.30 kg.

  12. Within- and between-herd prevalence variation of Mycobacterium avium subsp. paratuberculosis infection among control programme herds in Denmark (2011-2013).

    Science.gov (United States)

    Verdugo, Cristobal; Toft, Nils; Nielsen, Søren Saxmose

    2015-10-01

    This study aimed to estimate the between- (HTP) and within- (TP) herd true prevalence distribution of Mycobacterium avium subsp. paratuberculosis (MAP) infection in dairy cattle herds participating in the Danish MAP control programme. All herds enrolled in the programme between 2011 and 2013 were included in the analysis, and one annual milk-ELISA test of all lactating cows present in such herds was considered. A Bayesian latent class model was used to obtain HTP and TP posterior distributions for each year. The model adjusts for uncertainty in age-specific test sensitivity and prior prevalence estimates. Bayesian posterior probabilities were computed in order to compare prevalence between the years. A total of 665,700 samples were included in the study, from 221,914, 224,040, and 220,466 cows sourced from 1138, 1112, and 1059 herds in years 2011, 2012, and 2013, respectively. In that period, HTP estimates of 0.92 (95% posterior probability interval (PPI), 0.87-0.96), 0.78 (95% PPI, 0.74-0.83), and 0.75 (95% PPI, 0.71-0.78) were recorded, respectively. Low TP were observed, with population mean estimates of 0.08 (95% PPI, 0.07-0.08), 0.07 (95% PPI, 0.07-0.08), and 0.07 (95% PPI, 0.06-0.07) for the three consecutive years. Statistically-important differences were recorded for HTP and population mean TP estimates between years, indicating a trend for a decreasing level of MAP infection at both herd and animal level. Model results showed that MAP infection was widespread among the Dairy cattle herds participating in the Danish control programme, though in general it was kept at very low levels.

  13. Acculturation and metabolic syndrome risk factors in young Mexican and Mexican-American women.

    Science.gov (United States)

    Vella, Chantal A; Ontiveros, Diana; Zubia, Raul Y; Bader, Julia O

    2011-02-01

    Little is known about effects of acculturation on disease risk in young Mexican and Mexican-American women living in a border community. The purpose of this study was to examine relationships between acculturation and features of metabolic syndrome (MetS) in Mexican and Mexican-American women (n = 60) living in the largest US-Mexico border community. Acculturation was measured by the short acculturation scale for Hispanics and birthplace. Body composition was measured by Bod Pod and daily physical activity was measured by questionnaire and accelerometer. Increased acculturation was related to individual features of MetS and increased risk of MetS. These relationships were mediated by fat mass rather than inactivity. Fat mass mediates the relationships between acculturation and individual features of MetS in young Mexican and Mexican-American women. These findings suggest that fat mass, rather than inactivity, is an important contributor to disease risk in young Mexican and Mexican-American women living in a large US/Mexico border community.

  14. Bullying of Mexican Immigrant Students by Mexican American Students: An Examination of Intracultural Bullying

    Science.gov (United States)

    Mendez, Julian J.; Bauman, Sheri; Guillory, Raphael M.

    2012-01-01

    This article reports on a study using qualitative methods to investigate intracultural bullying, specifically, bullying between Mexican American (MA) and Mexican immigrant (MI) high school students. Previous research has reported specific cultural conflicts and discrimination within ethnic groups due to differences in acculturation. The purpose of…

  15. Political Participation and Social Capital among Mexicans and Mexican Americans in Central Illinois

    Science.gov (United States)

    Albarracin, Julia; Valeva, Anna

    2011-01-01

    This study tested the influence of bridging and bonding social capital in political participation while controlling for sociodemographic and psychological factors among Mexicans and Mexican Americans in Illinois. Bridging social capital significantly predicted two types of participation. Participants who felt their lives were linked to those of…

  16. [Prevalence of herd specific factors and limb disorders, and their associations in intensive swine production].

    Science.gov (United States)

    Lahrmann, Karl Heinz; Steinberg, Christina; Dahms, Susanne; Heller, Peter

    2003-01-01

    A longitudinal observational study in 180 pig breeding herds was performed to calculate prevalences of herd specific factors as well as typical limb disorders and to estimate their associations in a 2-step regression analysis. Regarding herd size, genetics, feeding and weight gain herds were distributed almost equal. The population density and the hygiene status were considered proper in most herds. In the farrowing units partially slatted floors of metal or plastic with slats > 9 mm, in the weaning units fully slatted floors of plastic, and in the rearing units fully slatted floors of concrete were most common. Less than 6% of the farms housed their pigs on solid concrete with straw bedding. Herd prevalences of fault floors varied between 18 and 43%. As a herd health problem (morbidity > 25%) claw hematomas and limb abrasions in just 1-week old piglets, overgrown claws and bursa swellings in weaned pigs, and bursa swellings in rearing pigs were wide spread. Leg deformations by osteopathy or arthritis occurred only sporadically. In the risk analysis claw hematomas of piglets were associated with slatted floors, particulary with slats concrete and rough floor surfaces at all. Overgrown claws and bursa swellings in weaned and in rearing pigs were associated with damaged, slippery or rough floor surfaces. Other associations were not detected. The quality of floor might be more important than the type of housing.

  17. Selenium status in cattle herds in Wallonia (Belgium: overview and health management

    Directory of Open Access Journals (Sweden)

    Youcef Mehdi

    2014-12-01

    Full Text Available Aim: Monitoring was performed in order to determine the Selenium (Se status of cattle herds in different agricultural areas in Wallonia (Belgium. Materials and Methods: The study included 114 heifers and 184 cows (82 dairy and 102 beef cows from 66 cattle farms situated in Wallonia. The Se status was assessed by measuring the glutathion peroxydase in red cells and converting it to the equivalent Se blood content. Results: The average blood concentrations of Se were very low. The Ardennes region was an area where the lowest Se status was recorded. The highest levels of Se in dairy cows and beef cows were recorded respectively in the limoneuse region and Famenne areas. The Se content in beef herds was lower compared with that of dairy herds (35 vs. 56 μg/L, p<0.01. Conclusion: On average over all the regions, 87% of animals were classified as deficient and only 13% of the animals were classified as adequate. The heifers from both dairy and beef herds in Wallonia exhibited a deficiency in Se classified as moderate to severe. The beef herds showed larger deficiencies compared with the dairy herds. Selenium deficiency can be prevented by ensuring adequate supplementation of deficient animals in Se deficient regions. An increased consumption of vitamin-mineral supplements, the use of Se-enriched fertilizers and ingredients containing high levels of Se can help to reduce or correct deficiencies recorded in cattle herds in Wallonia.

  18. Production impact & time to stability in sow herds infected with porcine epidemic diarrhea virus (PEDV).

    Science.gov (United States)

    Goede, Dane; Morrison, Robert B

    2016-01-01

    PEDV was first detected in United States in May, 2013. The virus spread through the swine industry and was reported in 30 US states by June, 2014 (Morrison and Goede, 2014). There are limited data describing the impact on production in sow farms. Veterinarians attempt to control the virus in sow herds with a program that stimulates herd immunity. There are no data on how long it takes with this control program to achieve a stable state of consistently produce weaned pigs that are not infected with the virus. This study involved participants and data from an existing program called the Swine Health Monitoring Project. Veterinarians were invited to share production data from 429 herds infected with PEDV. These data, in conjunction with diagnostic reports, were used to estimate the time required for the herd to produce PEDV PCR negative pigs and the production loss. Of the 429 infected herds that achieved the stable state of weaning PEDV PCR negative pigs, the median time was 28 weeks, ranging from 7 to 64 weeks. A median of 2.7 piglets/inventoried sow were not weaned and the average time required to recover to baseline production was 10 weeks in 183 herds. Herd infected in quarters 3 or 4 of the year had approximately twice the negative impact. These data are valuable for veterinarians in advising clients on the anticipated impact and time to re-achieve a stable state with regards to PEDV.

  19. BVDV and BHV-1 Infections in Dairy Herds in Northern and Northeastern Thailand

    Directory of Open Access Journals (Sweden)

    Chanlun A

    2004-12-01

    Full Text Available Bulk milk samples from 220 dairy herds were collected at 9 public milk collection centres in the northeastern and northern Thailand, and a subset of 11 herds was selected for individual testing. The samples were tested for presence of antibodies to BVDV and BHV-1 using an indirect ELISA. The results from the bulk milk testing demonstrated a moderate level of exposure to BVDV and BHV-1 (73% and 67%, respectively. However, the low proportion of herds with high BVDV antibody-levels (13% and the low within-herd seroprevalence of BVDV and BHV-1 in the 11 herds (24% and 5%, respectively, particularly among the young stock (15% and 0%, respectively, demonstrated a low prevalence of active BVDV infection and a low rate of reactivation of latent BHV-1. The presence of a self-clearance process was also indicated by the results from the individual testing. Moreover, a surprisingly low prevalence of BVDV and BHV-1 antibody-positive herds at one of the milk centres was found. This centre was established 5–10 years before the others. Our impression is that this reflects the self-clearance process, where consecutive replacement of imported infected animals without further spread has resulted in a nearly total elimination of the infections. Based on our experiences and on these results we are convinced that this process can continue if there is awareness of herd biosecurity. This is especially important in the context of a future intensification of the dairy production.

  20. Managerial and environmental determinants of clinical mastitis in Danish dairy herds

    Directory of Open Access Journals (Sweden)

    Houe Hans

    2008-02-01

    Full Text Available Abstract Background Several management and environmental factors are known as contributory causes of clinical mastitis in dairy herd. The study objectives were to describe the structure of herd-specific mastitis management and environmental factors and to assess the relevance of these herd-specific indicators to mastitis incidence rate. Methods Disease reports from the Danish Cattle Data Base and a management questionnaire from 2,146 herds in three Danish regions were analyzed to identify and characterize risk factors of clinical mastitis. A total of 94 (18 continuous and 76 discrete management and production variables were screened in separate bivariate regression models. Variables associated with mastitis incidence rate at a p-value Results Three latent factors (quality of labor, region of Denmark and claw trimming, and quality of outdoor holding area were identified from 14 variables. Daily milk production per cow, claw disease, quality of labor and region of Denmark were found to be significantly associated with mastitis incidence rate. A common multiple regression analysis with backward and forward selection procedures indicated there were 9 herd-specific risk factors. Conclusion Though risk factors ascertained by farmer-completed surveys explained a small percentage of the among-herd variability in crude herd-specific mastitis rates, the study suggested that farmer attitudes toward mastitis and lameness treatment were important determinants for mastitis incidence rate. Our factor analysis identified one significant latent factor, which was related to labor quality on the farm.

  1. Seroprevalence of and risk factors for brucellosis of goats in herds of Michoacan, Mexico.

    Science.gov (United States)

    Solorio-Rivera, J L; Segura-Correa, J C; Sánchez-Gil, L G

    2007-12-14

    Our objectives were to estimate the seroprevalence of Brucella melitensis, and to identify some risk factors associated with goat seropositivity in Michoacan, Mexico. Blood samples were collected from 5114 animals from 79 herds. Sera were tested for antibodies against B. melitensis using the Rose Bengal plate test and the complement-fixation test. Information regarding the herds and each animal sampled were recorded through a personal interview at the farm. We used random-effects multivariable logistic regression to analyze our data. Fifty-six herds of the 79 tested had at least one seropositive animal. The animal-level true seroprevalence was 9.8% (CI=8.8, 10.7). Animals in large herds (>34 animals), in herds with high stock density (>3.5 animals/m(2)) or animals >24 months old had higher odds of seropositivity (2.0, 1.7 and 1.8, respectively) than those in small herds, in herds with low stock density or animals < or =24 months old.

  2. Relationship between biosecurity and production/antimicrobial treatment characteristics in pig herds.

    Science.gov (United States)

    Laanen, M; Persoons, D; Ribbens, S; de Jong, E; Callens, B; Strubbe, M; Maes, D; Dewulf, J

    2013-11-01

    The biosecurity status of 95 breeder-finisher pig herds was quantified using a risk-based weighted scoring system. Data relating to herd-, farmer- and production-characteristics and to the prophylactic use of antimicrobials were also collected. The average external biosecurity score (measures to prevent pathogens from entering a herd) was 65 (range, 45-89) and the average internal score (measures to reduce the within-herd spread of pathogens) was 52 (range, 18-87). External scores were positively associated with herd size, while internal scores were negatively associated with both 'age of buildings' and 'years of experience of the farmer', indicating that biosecurity is generally better implemented in larger herds, in more modern facilities and by younger farmers. External and internal biosecurity scores were positively associated with daily weight gain and negatively associated with feed conversion ratio of fattening pigs. Internal scores were negatively associated with disease treatment incidence, suggesting that improved biosecurity might help in reducing the amount of antimicrobials used prophylactically. This study demonstrates and quantifies a clear link between biosecurity and both production- and antimicrobial treatment-related criteria in pig herds.

  3. Effects of herd management practices on somatic cell counts in an arid climate

    Directory of Open Access Journals (Sweden)

    Ali Sadeghi-Sefidmazgi

    2014-09-01

    Full Text Available The objective of this study was to evaluate associations between average lactation somatic cell counts (SCC and herd management practices in an arid climate. A total of 38,530 average lactation SCC records for 10,216 Holstein cows gathered on 25 dairy farms from January 2009 to October 2012 in Isfahan (Iran were analyzed. Average lactation SCC (cells × 1,000 was 250.79 ranging from 90.31 to 483.23 cells/mL across investigated farms. Herd-level management factors associated with average lactation SCC were determined separately using mixed linear models in the MIXED procedure with average lactation somatic cell score (SCS included as the dependent variable. Some of the management practices associated with low average lactation SCS included sawdust combined with sand bedding, using automatic cup removers, disinfection of the teats by dipping into disinfectant, using washable towels for teat cleaning, free-stall barns, wet disposable tissue for udder washing, wearing gloves during milking and the use of humidifiers and shade. Lower-production herds and larger-size herds had lower average lactation somatic cell counts. Most herd management practices associated with average lactation SCC in dairy herds in the arid region of Isfahan are in agreement with most previous studies. However, different results are found for use of humidifier, bedding materials and herd size.

  4. Estimating the number of undetected multi-resistant Salmonella Typhimurium DT104 infected pig herds in Denmark

    DEFF Research Database (Denmark)

    Rugbjerg, Helene; Wingstrand, Anne; Hald, Tine;

    2004-01-01

    In Denmark, the detection of multi-resistant Salmonella Typhimurium DT104 (MRDT104)-infected pig herds relies on the national Salmonella surveillance programme at the farm and slaughterhouse levels of production. With the surveillance sampling protocol and the diagnostic methods currently used...... with MRDT104 from 1 August 2001 till 31 July 2002 (90% CI [63, 228]). In comparison, 33 (32%) infected herds were detected in this period. The predicted proportion of undetected herds varied considerably with herd type. We infer that the proportion of detected MRDT104 infected herds depended...

  5. Population ecology of two woodland caribou herds in the southern Yukon

    Directory of Open Access Journals (Sweden)

    Richard Farnell

    1996-01-01

    Full Text Available Since the mid 1980's, the Aishihik herd of woodland caribou (Rangifer tarandus caribou declined from approximately 1500 to 583 animals. During the same period a nearby herd, the Wolf Lake Herd increased from approximately 664 to 1249 animals. This paper compares aspects of the ecology of these two herds to determine how these relationships conform to a general model of caribou population ecology described by Seip (1992. Comparisons include caribou demographic characteristics and distribution patterns, predator densities, abundance of alternate prey, human hunting and snow depth on caribou winter range. Ecological differences between herds were apparent in the ratio of prime bulls to cows, the abundance of moose (Alces alces, the occurrence of coyotes (Canis latrans, late winter snow conditions, and access to hunting. We hypothesize that the Wolf Lake herd was able to grow because wolves {Canis lupus preyed mainly on the relatively abundant moose population. A highly clumped winter caribou distribution may have further reduced the impact of wolf predation on the Wolf Lake herd. In contrast, the decline of the Aishihik herd was accompanied by a relative scarcity of moose, few prime aged caribou bulls probably due to a more liberal trophy harvest, and wider late-winter dispersion that offered wolves greater access to caribou. The decline may have been exaggerated by the peak in the snowshoe hare (Lepus americanus cycle which may have temporarily improved wolf pup survival. We suspect that moose are normally the primary prey of wolves in the Yukon and that a decline in moose eventually results in their being too scarce to offer an economical prey choice, prompting a prey switch to caribou. Results of our analyses conform incompletely to Seip's (1992 model for woodland caribou population ecology, particularly because the Wolf Lake herd prospered where moose were relatively abundant.

  6. The Effect of Wind on Coxiella burnetii Transmission Between Cattle Herds: a Mechanistic Approach.

    Science.gov (United States)

    Nusinovici, S; Hoch, T; Brahim, M L; Joly, A; Beaudeau, F

    2017-04-01

    There is a consensus that wind plays a key role in the transmission of Coxiella burnetii, the causative agent of Q fever, between ruminants and from ruminants to humans. However, no observational study so far has focused on the mechanisms associated with this airborne transmission. This study applied a mechanistic epidemiological approach to investigate the processes underlying the wind effect and to assess its influence on the risk for a dairy herd to become C. burnetii infected. Ninety-five dairy cattle herds located in the Finistère department (western France) were subjected to samplings of bulk tank milk and indoor dust every 4 months over a 1-year period to determine their C. burnetii status using PCR tests. A total of 27 incident herd-periods (negative-tested on both PCR tests and becoming positive-tested at least once at the subsequent sampling time) and 71 negative herd-periods were retained for analysis. Using logistic regression, we assessed the effect of (i) the cumulated number of bacteria in herds located under the main wind direction and (ii) the mean wind speed in this area, on a given herd's risk of becoming incident. Compared to herds in areas with low wind speed (≤5.5 m/s), the risk was significantly higher (OR = 3.7) in herds in areas with high wind speed (>5.5 m/s) and high bacterial load (>10), whereas it was not significantly different from unity in other situations. In agreement with our assumptions, C. burnetii transmission to a previously infection-free herd occurs only when (i) the wind transporting from infected sources and (ii) the load in the contaminated particles/aerosols generated are high enough to act jointly. © 2015 Blackwell Verlag GmbH.

  7. Economic effects of exposure to bovine viral diarrhea virus on dairy herds in New Zealand.

    Science.gov (United States)

    Heuer, C; Healy, A; Zerbini, C

    2007-12-01

    The economic loss to dairy farmers associated with bovine viral diarrhea virus (BVDV) is believed to be high in New Zealand, but no estimates are yet available. The aim was therefore to estimate the economic loss associated with BVDV in dairy herds in New Zealand. Bulk tank milk (BTM) from a random sample of 590 herds from the Northland, Bay of Plenty, and Waikato regions was tested for antibody against BVDV. The inhibition percentage (sample to positive ratio), based on a threshold validated in an earlier study, was used to indicate herd-level infection. Herd reproductive indices, herd lactation-average somatic cell counts, and herd average production of milk solids were regressed on BTM inhibition percentage. Herd averages of the overall annual culling rate, the rate of culling because of failure to conceive, the proportion of physiological inter-service intervals, the first-service conception rate, the pregnancy rate at the end of mating, and somatic cell counts were not associated with BVDV antibody in BTM. Abortion rates, rates of calving induction, the time from calving to conception, and the number of services per conception increased, however, whereas milk production decreased with increasing BVDV antibody in BTM. The results indicated significant reproductive and production loss associated with the amount of BVDV antibody in BTM. Total loss attributable to infection with BVDV was similar to reports from other countries and estimated as NZ$87 per cow and year in affected herds, and NZ$44.5 million per year for the New Zealand dairy industry based on an estimated 14.6% affected herds. The loss estimate excludes added cost and negative consequences with respect to animal welfare attributable to increased induction rates, and a greater incidence of production disease because of BVD-induced immune suppression.

  8. An assessment of dairy herd bulls in southern Australia: 1. Management practices and bull breeding soundness evaluations.

    Science.gov (United States)

    Hancock, A S; Younis, P J; Beggs, D S; Mansell, P D; Stevenson, M A; Pyman, M F

    2016-12-01

    In the pasture-based, seasonally calving dairy herds of southern Australia, the mating period usually consists of an initial artificial insemination period followed by a period of natural service using herd bulls. Bull breeding soundness evaluations (BBSE) were performed on 256 bulls from 32 dairy herds in southwest Victoria, using guidelines produced by the Australian Cattle Veterinarians, before and immediately after a single natural mating period. At the same time, herd managers were questioned regarding the management of the bulls. The objectives of this study were to describe the management practices of dairy herd bulls; to describe the causes of increased risk of reduced fertility in dairy herd bulls, as measured by a standard BBSE; and to describe the reasons for bull removal by herd managers during mating. At the premating BBSE, 19.5% of bulls were classified as high risk of reduced fertility, mostly due to physical abnormalities and reduced semen quality. At the postmating BBSE, 36.5% of bulls were classified as high risk of reduced fertility, mostly due to physical abnormalities, primarily lameness. Of the bulls used, 15.9% were removed from normal mating use by the herd manager, predominantly due to lameness and injuries. A premating BBSE is recommended in dairy herd bulls to identify bulls at risk of reduced fertility. Lameness is the most common problem in dairy herd bulls during the natural mating period, and risk factors associated with lameness in these bulls should be identified to better manage herd bulls.

  9. Spread of Coxiella burnetii between dairy cattle herds in an enzootic region: modelling contributions of airborne transmission and trade.

    Science.gov (United States)

    Pandit, Pranav; Hoch, Thierry; Ezanno, Pauline; Beaudeau, François; Vergu, Elisabeta

    2016-04-05

    Q fever, a worldwide zoonotic disease caused by Coxiella burnetii, is a looming concern for livestock and public health. Epidemiological features of inter-herd transmission of C. burnetii in cattle herds by wind and trade of cows are poorly understood. We present a novel dynamic spatial model describing the inter-herd regional spread of C. burnetii in dairy cattle herds, quantifying the ability of airborne transmission and animal trade in C. burnetii propagation in an enzootic region. Among all the new herd infections, 92% were attributed to airborne transmission and the rest to cattle trade. Infections acquired following airborne transmission were shown to cause relatively small and ephemeral intra-herd outbreaks. On the contrary, disease-free herds purchasing an infectious cow experienced significantly higher intra-herd prevalence. The results also indicated that, for short duration, both transmission routes were independent from each other without any synergistic effect. The model outputs applied to the Finistère department in western France showed satisfactory sensitivity (0.71) and specificity (0.80) in predicting herd infection statuses at the end of one year in a neighbourhood of 3 km around expected incident herds, when compared with data. The model developed here thus provides important insights into the spread of C. burnetii between dairy cattle herds and paves the way for implementation and assessment of control strategies.

  10. The effect of becoming BVDV-free on fertility and udder health in Dutch dairy herds.

    Science.gov (United States)

    Berends, I M G A; Swart, W A J M; Frankena, K; Muskens, J; Lam, T J G M; van Schaik, G

    2008-04-17

    The aim of the study was to investigate the effect of BVDV-free certification of dairy herds on fertility and udder health. Cases were defined as dairy herds that had at least one BVDV-antigen positive animal, subsequently gained the BVDV-free status by participating in the BVDV-control programme of the Animal Health Service (AHS) and maintained this status for at least 2 years. Controls had an unknown status for BVDV and two controls were matched to one case by region and herd size. Data concerning fertility and milk production of all herds were provided by The Dutch Royal Cattle Syndicate (NRS). After validation, data of 79,607 cows of 392 case herds and 124,831 cows of 730 control herds were analysed on ten fertility and three udder health parameters. For the analyses all observations were aggregated at herd level. To account for the matching, differences for fertility parameters were calculated between each of the two pairs of case-control within a matching code. The analyses were performed with these differences as dependent variables. Mixed models and GEE models were used for the statistical analyses of fertility and udder health. Case herds had a significantly lower abortion rate in the BVDV-free period than controls herds (10.3% versus 11.6%, P<0.01) while there was no significant difference for the other fertility parameters. There was no effect on mastitis prevalence or bulk-milk SCC but the mastitis incidence significantly decreased for case herds in the BVDV-free period (cases 0.6 % lower than controls, P<0.05). In our study the effect of getting the BVDV-free status may have been underestimated for several reasons like an unknown status for control herds, not knowing when an acute infection occurred in case herds and not knowing the management for both cases and controls. Interestingly, both significant variables, being abortions and mastitis incidence, are parameters that are more difficult to influence by the farmer than the other parameters (e

  11. UNA EXPLICACIÓN DEL EFECTO HERDING DESDE EL MERCADO DE DERIVADOS

    OpenAIRE

    NATIVIDAD BLASCO DE LAS HERAS; SANDRA FERRERUELA GARCÉS; PILAR CORREDOR CASADO

    2010-01-01

    El objetivo de este trabajo es contribuir a la explicación del comportamiento imitador (herding) aportando la perspectiva del mercado de derivados. Para ello se analiza la intensidad de herding en el mercado de contado en momentos especialmente relevantes en el mercado de derivados como es el vencimiento. La medida de herding empleada es la propuesta por Patterson y Sharma (2006). El periodo analizado comprende desde el año 1997 hasta el 2003, lo que permite estudiar aspectos como la madurez ...

  12. Using herd records to monitor transition cow survival, productivity, and health.

    Science.gov (United States)

    Nordlund, Kenneth V; Cook, Nigel B

    2004-11-01

    There is no single monitor that can fully characterize the success of a transition cow management program in a herd. Rather we must rely on a group of key monitors. Table 5 outlines the key indices and targets that we use in herd investigations. By using these monitors, effective transition cow programs can be differentiated from problematic ones, and many of the problems can be resolved for the good of the herd owners, dairy laborers, and most of all, the cows. Development of more sophisticated monitors and software with stronger epidemiologic structure will allow for better analysis of programs in the future.

  13. Some reproductive indexes of thirty dairy herds in the Po valley

    Directory of Open Access Journals (Sweden)

    C. Cerioli

    2011-03-01

    Full Text Available The need of increasing the daily milk yield often has negative backup on herd fertility (Westwood et al., 2002. Culling because of reproductive failure is a cost in dairy breeding. The reproductive efficiency is often expressed as days open (DOPN or calving interval. However, these indexes are a function of the pregnancy rate (PR which is calculated as the heat detection rate (HDR times the conception rate (CR (Ferguson, 1991. Thus, the herd reproductive performance is affected by HDR and CR (Maatje et al., 1997; Nir, 1996, Ferguson, 1996. This work was conducted to estimate reproductive efficiency of cows from thirty herds of the Po valley.........

  14. The roles of mean residence time on herd behavior in a financial market

    Science.gov (United States)

    Li, Jiang-Cheng; Li, Yun-Xian; Tang, Nian-Sheng; Mei, Dong-Cheng

    2016-11-01

    We investigate the herd behavior of stock prices in a finance system with the Heston model. Based on parameter estimation of the Heston model obtained by minimizing the mean square deviation between the theoretical and empirical return distributions, we simulate mean residence time of positive return (MRTPR). Plots of MRTPR against the amplitude or mean reversion of volatility demonstrate a phenomenon of herd behavior for a positive cross correlation between noise sources of the Heston model. Also, for a negative cross correlation, a phenomenon of herd behavior is observed in plots of MRTPR against the long-run variance by increasing amplitude or mean reversion of volatility.

  15. An observational study of Corynebacterium bovis in selected Ontario dairy herds.

    OpenAIRE

    1983-01-01

    An observational study of Corynebacterium bovis was conducted in 74 Ontario dairy herds. The levels of infection with C. bovis were 19.9, 36.2 and 85.6% at the quarter, cow and herd level, respectively. Teat disinfection was found to be the variable best able to distinguish between herds with a high or low C. bovis quarter infection rate. Mean total milk somatic cell counts for 1103 quarters and 107 cows infected with only C. bovis ranged between 150,000 and 200,000/mL and were significantly ...

  16. Evaluation of test-strategies for estimating probability of low prevalence of paratuberculosis in Danish dairy herds

    DEFF Research Database (Denmark)

    Sergeant, E.S.G.; Nielsen, Søren S.; Toft, Nils

    2008-01-01

    . Using this model, five herd-testing strategies were evaluated: (1) milk-ELISA on all lactating cows; (2) milk-ELISA on lactating cows 4 years old; (4) faecal culture on all lactating cows; and (5) milk-ELISA plus faecal culture in series on all lactating cows. The five testing strategies were evaluated...... using observed milk-ELISA results from 19 Danish dairy herds as well as for simulated results from the same herds assuming that they were uninfected. Whole-herd milk-ELISA was the preferred strategy, and considered the most cost-effective strategy of the five alternatives. The five strategies were all...... efficient in detecting infection, i.e. estimating a low Pr-Low in infected herds, however, Pr-Low estimates for milk-ELISA on age-cohorts were too low in simulated uninfected herds and the strategies involving faecal culture were too expensive to be of practical interest. For simulated uninfected herds...

  17. Aujeszky's disease and the effects of infection on Japanese swine herd productivity: a cross-sectional study.

    Science.gov (United States)

    Yamane, Itsuro; Ishizeki, Sayoko; Yamazaki, Hisanori

    2015-05-01

    Pseudorabies virus (PRV) is endemic in some regions of Japan. We investigated the effects of PRV infection status on herd productivity. Serum samples were obtained from 48 swine herds in Japan. Within each herd, three serum samples were obtained from growing pigs at four different ages, as well as from sows in low and high parity groups. Sera were tested for antibodies against wild-type PRV via competitive ELISA. Herds were classified into PRV positive and negative groups based on serological results. Herds infected with PRV exhibited postweaning mortalities (6.84%) that were significantly (P=0.0018) higher than those in unaffected herds (4.73%). Because of the reduced productivity in PRV positive herds, the current PRV eradication program must be strengthened.

  18. Estimation of the relative impact of treatment and herd management practices on prevention of digital dermatitis in French dairy herds.

    Science.gov (United States)

    Relun, A; Lehebel, A; Bruggink, M; Bareille, N; Guatteo, R

    2013-07-01

    The purpose of this study was to concurrently estimate the effect of different digital dermatitis (DD) treatment regimens and herd management practices on the occurrence of a new DD lesion. A controlled clinical trial was conducted and involved 4678 dairy cows from 52 French dairy farms where DD was endemic. Farms were allocated by minimisation to one of 4 treatment regimens, varying through the mode (footbath or collective spraying) and the frequency of application (2 days every 4 weeks or fortnightly). They were visited 7 times every 4 weeks by 14 trained investigators. Frailty Cox proportional hazards models were used to estimate the relative effect of potential risk factors and treatment practices on the time until the first occurrence of a DD lesion. At herd level, high initial DD prevalence strongly increased the risk for DD occurrence (HR=1.93, CI 1.23-3.04), as well as absence of hoof-trimming (HR=1.75, CI 1.36-2.27) and poor leg cleanliness (HR=2.44, CI 1.80-3.31). At animal level, Holstein breed (HR=1.92, CI 1.35-3.57) and high-productive cows (HR=1.26, CI 1.01-1.56) were identified to be at higher risk for DD compared to Normande breed and low-productive cows, respectively. Compared to individual topical antibiotic treatments alone, collective treatments tended to decrease the risk of DD occurrence only when applied over 2 days at least every fortnight (HR range=0.64-0.73). Copyright © 2013 Elsevier B.V. All rights reserved.

  19. Adjusting for multiple clinical observers in an unbalanced study design using latent class models of true within-herd lameness prevalence in Danish dairy herds.

    Science.gov (United States)

    Otten, N D; Toft, N; Houe, H; Thomsen, P T; Sørensen, J T

    2013-11-01

    The elimination of misclassification bias introduced by multiple observers was evaluated and discussed based on an illustrative example using lameness prevalence in 80 Danish dairy herds. Data from 5073 cows from loose-housed cubicle herds larger than 100 cows were included in the analysis. Four trained observers performed clinical scoring on cow level and undertook a calibration test with 39 video sequences. The calibration test served both the purpose of estimating inter-observer agreement (PABAK=0.69) in accordance with previous results and to estimate the sensitivity (Se) and specificity (Sp) for each observer. In the absence of a gold standard for the clinical observations, a latent class analysis (LCA) evaluating the true within-herd lameness prevalence was used. Sensitivity amongst observers was fairly low (0.24-0.81) inducing a general underestimation of the true prevalence. Comparative analyses were made to assess the effect of grazing on the lameness prevalence in order to demonstrate the consequences of using unadjusted apparent prevalences (AP) compared to the true prevalences (TP). Lameness prevalence was higher in grazing herds using AP estimates (19.0% zero-grazing, 20.2% grazing); while the TP estimates showed the expected higher lameness prevalence in zero-grazing herds (42.3% vs. 35.9%). Hence, this study emphasizes the importance of adjusting for observer Se and Sp to obtain true prevalence and avoid false interpretation.

  20. Genetic structure of African buffalo herds based on variation at the mitochondrial D-loop and autosomal microsatellite loci: Evidence for male-biased gene flow

    NARCIS (Netherlands)

    Hooft, van W.F.; Groen, A.F.; Prins, H.H.T.

    2003-01-01

    Sexual differences in herding behaviour of African buffalo (Syncerus caffer) were studied by analysing at the herd level mitochondrial D-loop hypervariable region I and fourteen autosomal microsatellites. Three herds from Arusha National Park in Tanzania were analysed with mtDNA and five herds from

  1. When can a veterinarian be expected to detect classical swine fever virus among breeding sows in a herd during an outbreak?

    NARCIS (Netherlands)

    Engel, B.; Bouma, A.; Stegeman, J.A.; Buist, W.; Elbers, A.R.W.; Kogut, J.; Döpfer, D.; Jong, de M.C.M.

    2005-01-01

    The herd sensitivity (HSe) and herd specificity (Hsp) of clinical diagnosis of an infection with classical swine fever (CSF) virus during veterinary inspection of breeding sows in a herd was evaluated. Data gathered from visits to herds during the CSF outbreak in 1997¿1998 in The Netherlands were us

  2. Caprine prion gene polymorphisms are associated with decreased incidence of classical scrapie in goat herds in the United Kingdom

    Directory of Open Access Journals (Sweden)

    Goldmann Wilfred

    2011-10-01

    Full Text Available Abstract The application of genetic breeding programmes to eradicate transmissible spongiform encephalopathies in goats is an important aim for reasons of animal welfare as well as human food safety and food security. Based on the positive impact of Prnp genetics on sheep scrapie in Europe in the past decade, we have established caprine Prnp gene variation in more than 1100 goats from the United Kingdom and studied the association of Prnp alleles with disease phenotypes in 150 scrapie-positive goats. This investigation confirms the association of the Met142 encoding Prnp allele with increased resistance to preclinical and clinical scrapie. It reveals a novel association of the Ser127 encoding allele with a reduced probability to develop clinical signs of scrapie in goats that are already positive for the accumulation of disease-specific prion protein in brain or periphery. A United Kingdom survey of Prnp genotypes in eight common breeds revealed eleven alleles in over thirty genotypes. The Met142 encoding allele had a high overall mean allele frequency of 22.6%, whereas the Ser127 encoding allele frequency was considerably lower with 6.4%. In contrast, a well known resistance associated allele encoding Lys222 was found to be rare (0.9% in this survey. The analysis of Prnp genotypes in Mexican Criollas goats revealed nine alleles, including a novel Phe to Leu substitution in codon 201, confirming that high genetic variability of Prnp can be found in scrapie-free populations. Our study implies that it should be feasible to lower scrapie prevalence in goat herds in the United Kingdom by genetic selection.

  3. Caprine prion gene polymorphisms are associated with decreased incidence of classical scrapie in goat herds in the United Kingdom.

    Science.gov (United States)

    Goldmann, Wilfred; Ryan, Kelly; Stewart, Paula; Parnham, David; Xicohtencatl, Rosa; Fernandez, Nora; Saunders, Ginny; Windl, Otto; González, Lorenzo; Bossers, Alex; Foster, James

    2011-10-31

    The application of genetic breeding programmes to eradicate transmissible spongiform encephalopathies in goats is an important aim for reasons of animal welfare as well as human food safety and food security. Based on the positive impact of Prnp genetics on sheep scrapie in Europe in the past decade, we have established caprine Prnp gene variation in more than 1100 goats from the United Kingdom and studied the association of Prnp alleles with disease phenotypes in 150 scrapie-positive goats. This investigation confirms the association of the Met142 encoding Prnp allele with increased resistance to preclinical and clinical scrapie. It reveals a novel association of the Ser127 encoding allele with a reduced probability to develop clinical signs of scrapie in goats that are already positive for the accumulation of disease-specific prion protein in brain or periphery. A United Kingdom survey of Prnp genotypes in eight common breeds revealed eleven alleles in over thirty genotypes. The Met142 encoding allele had a high overall mean allele frequency of 22.6%, whereas the Ser127 encoding allele frequency was considerably lower with 6.4%. In contrast, a well known resistance associated allele encoding Lys222 was found to be rare (0.9%) in this survey. The analysis of Prnp genotypes in Mexican Criollas goats revealed nine alleles, including a novel Phe to Leu substitution in codon 201, confirming that high genetic variability of Prnp can be found in scrapie-free populations. Our study implies that it should be feasible to lower scrapie prevalence in goat herds in the United Kingdom by genetic selection.

  4. Eficiência produtiva em vacas primíparas das raças Aberdeen Angus e Charolês Productive efficiency of Angus and Charolais primiparous cows

    Directory of Open Access Journals (Sweden)

    Edson Luis de Azambuja Ribeiro

    2001-02-01

    Full Text Available Este trabalho foi conduzido com o objetivo de avaliar o desempenho produtivo de vacas de corte. Foram utilizadas 30 vacas da raça Aberdeen Angus e 32 da raça Charolês primíparas, prenhes no início do experimento, com bezerros puros ou mestiços Nelore. As vacas foram submetidas a diferentes tratamentos alimentares durante o inverno e a primavera: T1 - pastagem natural, T2 - pastagem cultivada por 60 dias (24 horas/dia, do início de setembro ao início de novembro, T3 - acesso à pastagem cultivada por duas horas diárias, por um período de 60 dias (de início de julho ao início de setembro, T4 - acesso à pastagem cultivada por duas horas diárias, por um período de 60 dias (de início de julho ao início de setembro, e mais 60 dias (24 horas/dia de pastagem cultivada do início de setembro ao início de novembro. As medidas de eficiência produtiva foram: EPPARTO = (P205/PVP*100; EPDESMAME = (P205/PVD*100; EPMBPARTO = (P205/PVP0,75; EPMBDESMAME = (P205/PVD0,75; e EPNDT = NDTTOTAL/P205, em que P205 é o peso ao desmame dos bezerros; PVP e PVD, os pesos das vacas ao parto e ao desmame, respectivamente; e NDTTOTAL, a exigência em energia para manutenção e produção de leite das vacas. As vacas Aberdeen Angus, com bezerros machos e aquelas com bezerros mestiços, foram mais eficientes. Vacas que utilizaram a pastagem cultivada por um período de tempo maior (T4 tiveram melhor desempenho do que aquelas que permaneceram apenas em pastagem natural(T1; as vacas dos outros tratamentos tiveram desempenhos intermediários.The objective of this work was to evaluate the productive efficiency of beef cows. Thirty Angus and 32 Charolais primiparous cows, pregnant at the beginning of the experiment with straightbred or crossbred calves, were evaluated. The cows were submitted to different feeding management during winter and spring: T1 -- Native pasture, T2 -- Cultivated pasture for 60 days (24 hours/day, from early September to early November, T3

  5. Legal Status and Wage Disparities for Mexican Immigrants

    Science.gov (United States)

    Hall, Matthew; Greenman, Emily; Farkas, George

    2010-01-01

    This article employs a unique method of inferring the legal status of Mexican immigrants in the Survey of Income and Program Participation to offer new evidence of the role of legal authorization in the United States on workers' wages. We estimate wage trajectories for four groups: documented Mexican immigrants, undocumented Mexican immigrants,…

  6. The Representation of "Curanderismo" in Selected Mexican American Works

    Science.gov (United States)

    Pabon, Melissa

    2007-01-01

    "Curanderismo," a Mexican folk practice, is a prevalent subject in Mexican American literature. Because much of the presence of "curanderismo" in Mexican American literature is only explored in ethnographic studies, the purpose of this study is to examine the artistic representation of "curanderismo" in the novels "Bless Me, Ultima" by Rudolfo…

  7. Acculturation and Enculturation Trajectories among Mexican-American Adolescent Offenders

    Science.gov (United States)

    Knight, George P.; Vargas-Chanes, Delfino; Losoya, Sandra H.; Cota-Robles, Sonia; Chassin, Laurie; Lee, Joanna M.

    2009-01-01

    This study examines changes over time in ethnic affirmation/belonging and ethnic identity achievement, Spanish language use, English language use, Mexican/Mexican-American affiliation/identification and Anglo affiliation/identification in a sample of Mexican-American adolescents participating in a longitudinal study of juvenile offenders. The…

  8. Filial Responsibility Expectations among Mexican American Undergraduates: Gender and Biculturalism

    Science.gov (United States)

    Rudolph, Bonnie; Chavez, Mary; Quintana, Fernando; Salinas, Gilberto

    2011-01-01

    How Mexican American college students perceive responsibility for parental care is important as Mexican American elders' numbers increase. The authors applied mixed methods to investigate the impact of gender and biculturalism within this group. Two hundred and eighty-six Mexican American undergraduates completed the Hamon Filial Responsibility…

  9. Legal Status and Wage Disparities for Mexican Immigrants

    Science.gov (United States)

    Hall, Matthew; Greenman, Emily; Farkas, George

    2010-01-01

    This article employs a unique method of inferring the legal status of Mexican immigrants in the Survey of Income and Program Participation to offer new evidence of the role of legal authorization in the United States on workers' wages. We estimate wage trajectories for four groups: documented Mexican immigrants, undocumented Mexican immigrants,…

  10. Herd immunity and pneumococcal conjugate vaccine: a quantitative model.

    Science.gov (United States)

    Haber, Michael; Barskey, Albert; Baughman, Wendy; Barker, Lawrence; Whitney, Cynthia G; Shaw, Kate M; Orenstein, Walter; Stephens, David S

    2007-07-20

    Invasive pneumococcal disease in older children and adults declined markedly after introduction in 2000 of the pneumococcal conjugate vaccine for young children. An empirical quantitative model was developed to estimate the herd (indirect) effects on the incidence of invasive disease among persons >or=5 years of age induced by vaccination of young children with 1, 2, or >or=3 doses of the pneumococcal conjugate vaccine, Prevnar (PCV7), containing serotypes 4, 6B, 9V, 14, 18C, 19F and 23F. From 1994 to 2003, cases of invasive pneumococcal disease were prospectively identified in Georgia Health District-3 (eight metropolitan Atlanta counties) by Active Bacterial Core surveillance (ABCs). From 2000 to 2003, vaccine coverage levels of PCV7 for children aged 19-35 months in Fulton and DeKalb counties (of Atlanta) were estimated from the National Immunization Survey (NIS). Based on incidence data and the estimated average number of doses received by 15 months of age, a Poisson regression model was fit, describing the trend in invasive pneumococcal disease in groups not targeted for vaccination (i.e., adults and older children) before and after the introduction of PCV7. Highly significant declines in all the serotypes contained in PCV7 in all unvaccinated populations (5-19, 20-39, 40-64, and >64 years) from 2000 to 2003 were found under the model. No significant change in incidence was seen from 1994 to 1999, indicating rates were stable prior to vaccine introduction. Among unvaccinated persons 5+ years of age, the modeled incidence of disease caused by PCV7 serotypes as a group dropped 38.4%, 62.0%, and 76.6% for 1, 2, and 3 doses, respectively, received on average by the population of children by the time they are 15 months of age. Incidence of serotypes 14 and 23F had consistent significant declines in all unvaccinated age groups. In contrast, the herd immunity effects on vaccine-related serotype 6A incidence were inconsistent. Increasing trends of non

  11. Mexican forest fires and their decadal variations

    Science.gov (United States)

    Velasco Herrera, Graciela

    2016-11-01

    A high forest fire season of two to three years is regularly observed each decade in Mexican forests. This seems to be related to the presence of the El Niño phenomenon and to the amount of total solar irradiance. In this study, the results of a multi-cross wavelet analysis are reported based on the occurrence of Mexican forest fires, El Niño and the total solar irradiance for the period 1970-2014. The analysis shows that Mexican forest fires and the strongest El Niño phenomena occur mostly around the minima of the solar cycle. This suggests that the total solar irradiance minima provide the appropriate climatological conditions for the occurrence of these forest fires. The next high season for Mexican forest fires could start in the next solar minimum, which will take place between the years 2017 and 2019. A complementary space analysis based on MODIS active fire data for Mexican forest fires from 2005 to 2014 shows that most of these fires occur in cedar and pine forests, on savannas and pasturelands, and in the central jungles of the Atlantic and Pacific coasts.

  12. Effect of grazing on the cow welfare of dairy herds evaluated by a multidimensional welfare index

    DEFF Research Database (Denmark)

    Burow, E; Rousing, T; Thomsen, P T

    2013-01-01

    studied under different conditions. However, the effect of grazing on welfare, conceptualised as the multidimensional physical and mental state of the animal, has not yet been studied in contemporary cubicle loose-housing systems. The aim of our study was to investigate, based on a Welfare Quality (R......Structural development in the prime sector has led to increasing herd sizes and new barn systems, followed by less summer grazing for dairy cows in Denmark. Effects of grazing on single welfare measures in dairy cows - for example, the presence of integument alterations or mortality - have been......) inspired multidimensional dairy cow welfare assessment protocol, the within-herd effect of summer grazing compared with winter barn housing in Danish dairy herds with cubicle free-stall systems for the lactating cows. Our hypothesis was that cow welfare in dairy herds was better during summer grazing than...

  13. Southeastern Cooperative wildlife disease study: Tennessee National Wildlife Refuge deer herd health checks

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Enclosed are our reports on the deer herd health checks we conducted on the Duck River and Big Sandy Units, Tennessee National Wildlife Refuge, Humphrey and Henry...

  14. [Southeastern Cooperative wildlife disease study: Tennessee National Wildlife Refuge deer herd health checks

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Enclosed are the reports on the deer herd health checks conducted on the Big Sandy and Duck River Units of Tennessee National Wildlife Refuge, Henry and Humphrey...

  15. [Bison briefing paper for DOI bison meeting on the Fort Niobrara herd

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Briefing paper on the Fort Niobrara National Wildlife Refuge bison herd, presented at the Department of the Interior Bison Meeting, held in Billings, Montana, March...

  16. Invasion and transmission of Salmonella Kentucky in an adult dairy herd using approximate Bayesian computation

    National Research Council Canada - National Science Library

    Lu, Zhao; Mitchell, Rebecca M; Smith, Rebecca L; Karns, Jeffrey S; van Kessel, Jo Ann S; Wolfgang, David R; Schukken, Ynte H; Grohn, Yrjo T

    2013-01-01

    An outbreak of Salmonella Kentucky followed by a high level of sustained endemic prevalence was recently observed in a US adult dairy herd enrolled in a longitudinal study involving intensive fecal sampling...

  17. Assessing the potential impact of Salmonella vaccines in an endemically infected dairy herd

    Science.gov (United States)

    Salmonella spp. in cattle are contributing to bacterial foodborne disease for humans. Reduction of Salmonella prevalence in herds is important to prevent human Salmonella infections. Typical control measures are culling of infectious animals, vaccination, and improved hygiene management. Vaccines ha...

  18. A health assessment and calfhood mortality study of the northern Alaska Peninsula caribou herd

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Northern Alaska Peninsula caribou herd (NAP) has declined by 79% since 1993, however the reasons for the decline are not well documented. The NAP caribou are an...

  19. Herding of reindeer in relation to birds and mammals on the northern Seward Peninsula

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Impacts of herding reindeer on foot, air, ATV. Also discusses impacts of egg gathering, bird hunting, and predator management completed by subsistent and reindeer...

  20. Optimization of surveillance opf Bovine Viral Diarrhea in Danish dairy herds

    DEFF Research Database (Denmark)

    Foddai, Alessandro

    ELISA (Rønsholt et al., 1997; Bitsch et al., 1997) and the SVANOVIR ELISA (Juntti at al., 1987; Niskanen, 1993) were compared on milk and serum samples. The prevalence of antibody positive milking cows, which can be detected by each of those tests, was estimated by diluting positive individual milk...... dairy herds (e.g. after import of infected cattle) could be more difficult to detect compared to the past, due to the lower prevalence of antibody positive milking cows and the (expected) higher dilution of antibodies in bigger milk containers. Therefore, an evaluation and an eventual optimization...... of the BVD surveillance system in Danish dairy herds were considered necessary by the Danish Cattle Federation. In study I, we verified how the BVD herd prevalence, the herd size and the dilution of individual milk within the bulk tank milk (BTM) changed, between 2003 and 2010. Moreover, the Danish blocking...

  1. Dynamical properties of the herding voter model with and without noise

    Science.gov (United States)

    Rozanova, Liudmila; Boguñá, Marián

    2017-07-01

    Collective leadership and herding may arise in standard models of opinion dynamics as an interplay of a strong separation of time scales within the population and its hierarchical organization. Using the voter model as a simple opinion formation model, we show that, in the herding phase, a group of agents become effectively the leaders of the dynamics while the rest of the population follow blindly their opinion. Interestingly, in some cases such herding dynamics accelerates the time to consensus, which then becomes size independent or, on the contrary, makes the consensus nearly impossible. These behaviors have important consequences when an external noise is added to the system that makes consensus (absorbing) states to disappear. We analyze this model, which shows an interesting phase diagram, with a purely diffusive phase, a herding (or two-states) phase, and mixed phases where both behaviors are possible.

  2. Modelling the dynamics of the health-production complex in livestock herds

    DEFF Research Database (Denmark)

    Sørensen, J.T.; Enevoldsen, Carsten

    1992-01-01

    This paper reviews how the dynamics of the health-production complex in livestock herds is mimicked by livestock herd simulation models. Twelve models simulating the dynamics of dairy, beef, sheep and sow herds were examined. All models basically included options to alter input and output...... of reproductive animals in a manner which could be related to health problems. Direct effects of diseases on growth or milk production were, however, addressed in only a few models and were confined to a few basic relations if modelled. The lack of effects on individual animal production in the models may relate...... and their interactions could be studied by applying the same standards of analysis to simulated data as to real herd data. © 1992....

  3. CrossRef Experimental verification of the HERD prototype at CERN SPS

    CERN Document Server

    Dong, Yongwei; Wang, Junjing; Xu, Ming; Albergo, Sebastiano; Ambroglini, Filippo; Ambrosi, Giovanni; Azzarello, Philipp; Bai, Yonglin; Bao, Tianwei; Baldini, Luca; Battiston, Roberto; Bernardini, Paolo; Chen, Zhen; D'Alessandro, Raffaello; Duranti, Matteo; D'Urso, Domenico; Fusco, Piergiorgio; Gao, Jiarui; Gao, Xiaohui; Gargano, Fabio; Giglietto, Nicola; Hu, Bingliang; Li, Ran; Li, Yong; Liu, Xin; Loparco, Francesco; Lu, Junguang; Marsella, Giovanni; Mazziotta, Mario N; De Mitri, Ivan; Mori, Nicola; Orsi, Silvio; Oscar, Adriani; Pearce, Mark; Pohl, Martin; Ryde, Felix; Shi, Dalian; Spillantini, Piero; Su, Meng; Sun, Xin; Surdo, Antonio; Walter, Roland; Wang, Bo; Wang, Le; Wang, Ruijie; Wang, Zhigang; Wu, Bobing; Wu, Xin; Yan, Peng; Zhang, Li; Zhang, Shuangnan

    2016-01-01

    The High Energy cosmic-Radiation Detection (HERD) facility is one of several space astronomy payloads of the cosmic light house program onboard China's Space Station, which is planned for operation starting around 2020 for about 10 years. Beam test with a HERD prototype, to verify the HERD specifications and the reading out method of wavelength shifting fiber and image intensified CCD, was taken at CERN SPS in November, 2015. The prototype is composed of an array of 5*5*10 LYSO crystals, which is 1/40th of the scale of HERD calorimeter. Experimental results on the performances of the calorimeter are discussed. © (2016) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.

  4. Evaluation of techniques for assessing neonatal caribou calf mortality in the Porcupine Caribou Herd

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report discusses the evaluation of techniques for assessing neonatal caribou calf mortality in the Porcupine caribou herd in Arctic National Wildlife Refuge....

  5. Cow attributes, herd management, and reproductive history events associated with the risk of nonpregnancy in cow-calf herds in Western Canada.

    Science.gov (United States)

    Waldner, C L; García Guerra, A

    2013-04-15

    To identify herd management and cow characteristics associated with the reproductive success of cow-calf herds in Western Canada, 33,391 beef cows were followed from the beginning of the breeding season in 2001 through pregnancy testing in 2002. Breeding management and cow-level risk factors such as age, body condition score (BCS), and previous reproductive history, were measured through a series of herd visits by project personnel and records maintained by the herd owner. Pregnancy status was measured in 205 herds in the fall of 2001 and again in 200 herds in the fall of 2002. Cows least likely to be pregnant in the fall of the year were 10 years old or older, exposed to a bull less than 84 days, had a BCS ≤5 of 9 at pregnancy testing, <5 of 9 before calving, and lost condition between calving and the start of the breeding season, or had a prebreeding BCS <5 of 9 with a loss of condition between breeding and pregnancy testing. Other factors identified that decreased the likelihood of pregnancy in at least one of the 2 years included being a heifer or being a cow exposed to breeding after her first calf, and using a single bull on breeding pasture. Cows vaccinated for bovine viral diarrhea virus and infectious bovine rhinotracheitis and bred on community pastures were more likely to be pregnant than cows that were not vaccinated and bred on community pastures. Cows bred on community pastures that were not vaccinated were also less likely to be pregnant than cows that were not on community pastures regardless of vaccination status. Calving-associated events such as twin birth, Cesarean section or malpresentation, problems such as uterine prolapse or retained placentas, abortion or calf death within 1 hour after birth, or calving late after the start of the breeding season, were also associated with fewer pregnancies after accounting for all other factors.

  6. Exploring the value of routinely collected herd data for estimating dairy cattle welfare.

    Science.gov (United States)

    de Vries, M; Bokkers, E A M; van Schaik, G; Engel, B; Dijkstra, T; de Boer, I J M

    2014-02-01

    Routine on-farm assessment of dairy cattle welfare is time consuming and, therefore, expensive. A promising strategy to assess dairy cattle welfare more efficiently is to estimate the level of animal welfare based on herd data available in national databases. Our aim was to explore the value of routine herd data (RHD) for estimating dairy cattle welfare at the herd level. From November 2009 through March 2010, 7 trained observers collected data for 41 welfare indicators in a selected sample of 183 loose-housed and 13 tethered Dutch dairy herds (herd size: 10 to 211 cows) using the Welfare Quality protocol for cattle. For the same herds, RHD relating to identification and registration, management, milk production and composition, and fertility were extracted from several national databases. The RHD were used as potential predictors for each welfare indicator in logistic regression at the herd level. Nineteen welfare indicators were excluded from the predictions, because they showed a prevalence below 5% (15 indicators), or were already listed as RHD (4 indicators). Predictions were less accurate for 7 welfare indicators, moderately accurate for 14 indicators, and highly accurate for 1 indicator. By forcing to detect almost all herds with a welfare problem (sensitivity of at least 97.5%), specificity ranged from 0 to 81%. By forcing almost no herds to be incorrectly classified as having a welfare problem (specificity of at least 97.5%), sensitivity ranged from 0 to 67%. Overall, the best-performing prediction models were those for the indicators access to at least 2 drinkers (resource based), percentage of very lean cows, cows lying outside the supposed lying area, and cows with vulvar discharge (animal based). The most frequently included predictors in final models were percentages of on-farm mortality in different lactation stages. It was concluded that, for most welfare indicators, RHD have value for estimating dairy cattle welfare. The RHD can serve as a

  7. Evaluation of two dairy herd reproductive performance indicators that are adjusted for voluntary waiting period

    Directory of Open Access Journals (Sweden)

    Löf Emma

    2012-01-01

    Full Text Available Abstract Background Overall reproductive performance of dairy herds is monitored by various indicators. Most of them do not consider all eligible animals and do not consider different management strategies at farm level. This problem can be alleviated by measuring the proportion of pregnant cows by specific intervals after their calving date or after a fixed time period, such as the voluntary waiting period. The aim of this study was to evaluate two reproductive performance indicators that consider the voluntary waiting period at the herd. The two indicators were: percentage of pregnant cows in the herd after the voluntary waiting period plus 30 days (PV30 and percentage of inseminated cows in the herd after the voluntary waiting period plus 30 days (IV30. We wanted to assess how PV30 and IV30 perform in a simulation of herds with different reproductive management and physiology and to compare them to indicators of reproductive performance that do not consider the herd voluntary waiting period. Methods To evaluate the reproductive indicators we used the SimHerd-program, a stochastic simulation model, and 18 scenarios were simulated. The scenarios were designed by altering the reproductive management efficiency and the status of reproductive physiology of the herd. Logistic regression models, together with receiver operating characteristics (ROC, were used to examine how well the reproductive performance indicators could discriminate between herds of different levels of reproductive management efficiency or reproductive physiology. Results The logistic regression models with the ROC analysis showed that IV30 was the indicator that best discriminated between different levels of management efficiency followed by PV30, calving interval, 200-days not-in calf-rate (NotIC200, in calf rate at100-days (IC100 and a fertility index. For reproductive physiology the ROC analysis showed that the fertility index was the indicator that best discriminated

  8. Investigation of bovine venereal campyloacteriosis in beef cow herds in New Zealand.

    Science.gov (United States)

    McFadden, A M; Heuer, C; Jackson, R; West, D M; Parkinson, T J

    2005-02-01

    To determine regional prevalences of beef cow herds in New Zealand positive for Campylobacter fetus subsp venerealis antibodies in samples of vaginal mucus tested using an immunoglobulin (Ig) A enzyme-linked immunosorbent assay (ELISA), and to examine the suitability of the IgA ELISA for detecting infection with C. fetus subsp venerealis under field conditions in New Zealand. Vaginal mucus samples (n=1,230) collected from beef cow herds (n=125) throughout New Zealand (approximately 10 samples/herd) were tested for antibodies to C. fetus subsp venerealis using an IgA ELISA. Test results were compared between herds classified as having low, medium and high fertility based on pregnancy test results interpreted in relation to the duration of the mating period used. In addition, a small number of samples were collected from dairy cows that were mated using artificial insemination (AI) and had no contact with breeding bulls. The influence of putative risk factors for the spread of venereal disease and the effect of sample quality on the status of herds according to test results was assessed using multivariate logistical regression. Preputial washings from 54 bulls from nine herds classified as low fertility in which mucus samples from > or =3 cows were IgA antibody-positive were cultured for the presence of Campylobacter spp, and isolates of C. fetus subspecies were characterised using a polymerase chain reaction (PCR) test. One or more mucus samples was positive to the IgA ELISA in 70% of all herds tested. The prevalence of IgA antibody- positive individuals was >20% in most regions of New Zealand and did not differ significantly for cows from herds classified as high, medium or low fertility (28%, 26% and 23%, respectively; p=0.39). No relationship was found between mucus antibody status and age of breeding group, herd size, herd fertility, number of herds that female replacements or breeding bulls were sourced from, whether a serving ability test (SAT) was used to

  9. Predictors of the first between-herd animal movement for cattle born in 2002 in Ireland.

    Science.gov (United States)

    White, P; Frankena, K; O'Keeffe, J; More, S J; Martin, S W

    2010-12-01

    Movement of animals between farms represents a potential risk of bovine tuberculosis (BTB) and other disease transmission. The objectives of this study were to identify and quantify risk factors associated with the first between-herd movement of animals (denoted as risk move). A random sample of 1 percent of Irish calf births registered for 2002 (20,182 animals) was selected. Descriptive and survival analysis on movement over the period 2002-2005 was performed. A total of 12,119 (60%) of animals experienced a risk move over the 4-year study period. Among those that moved, 57% did so within the first 12 months of age. For animals in dairy herds, an early peak in risk move events was observed within the first 12 weeks of age; whereas in animals from suckler herds, a later risk move peak was observed between 21 and 36 weeks of age. The survival models identified a number of risk factors: two that appeared most important in predicting a risk move were gender and enterprise type. Males had a hazard ratio of 2.6 times that of females. The hazards for enterprise type, varied over time, thus a time-varying covariate (ent_type×ln(time)) was included in the Cox model. At 7 days of age, females in suckler herds were at 0.14 times the hazard of females in dairy herds for risk move, and over time, the hazards converged, equalised by day 140, and then diverged, so that by 4 years of age, females in suckler herds were at 4.64 times the hazard of females in dairy herds. Herds with a history of selling animals in previous years maintained that record during the study period with increased hazard of risk move. Enterprise type interacted with gender so that relative to females, males from dairy herds were at greater hazard of risk move than males from suckler herds. Hazard of risk move was also a function of ln (herd area), so that each doubling of farm area was accompanied by a 30.6% decrease in the hazards. The main conclusion was that risk of movement related disease transmission

  10. Risk factors for Brucella seropositivity in goat herds in eastern and western Uganda.

    Science.gov (United States)

    Kabagambe, E K; Elzer, P H; Geaghan, J P; Opuda-Asibo, J; Scholl, D T; Miller, J E

    2001-12-03

    Cross-sectional prevalences and risk factors for Brucella seropositivity in goats in eastern and western Uganda were investigated. Serum was collected from 1518 goats randomly selected from 145 herds which had been identified using multistage sampling. The brucellosis card test (CT) and the Brucella melitensis tube-agglutination test (TAT) were used in parallel to detect antibodies against B. abortus and B. melitensis, respectively. Interviewer-administered questionnaires were used to collect information on goat health and management. This information was used in multivariable logistic-regression models to determine the risk factors for Brucella seropositivity in goat herds. For each analysis, a herd was considered positive if at least one goat in the herd tested positive for antibodies against Brucella and negative if none was positive. Four percent (55/1480) of the goats screened with the CT had antibodies against Brucella. The reactors were distributed in 13% (19/145) of the herds. The most-important herd-level risk factors identified were use of a hired caretaker as the primary manager of the operation compared to owner/family members (adjusted odds ratio (OR)=8.1; 95% CI 1.6, 39.7), keeping sheep in addition to goats (OR=6.0; CI 1.5, 23.7) compared to having no sheep, and free browsing (OR=4.7; 95% CI 1.0, 20.7) when compared to tethering or zero-grazing. Using the TAT, 10% (141/1446) of the goats tested positive. The positives were distributed in 43% (63/145) of the herds. Free browsing (OR=6.7; 95% CI 2.7, 16.9) when compared to tethering or zero-grazing and lack of veterinary care (OR=2.9; CI 1.3, 6.7) were the most-important factors identified in the multivariable model for B. melitensis herd seropositivity. To explore/reduce the risk of misclassification in a secondary analysis, herds were reclassified as positive if at least one goat tested positive on both tests and negative if none of the goats was positive on any of the two tests. Using this

  11. Mexican Space Weather Service (SCIESMEX)

    Science.gov (United States)

    Gonzalez-Esparza, A.; De la Luz, V.; Mejia-Ambriz, J. C.; Aguilar-Rodriguez, E.; Corona-Romero, P.; Gonzalez, L. X.

    2015-12-01

    Recent modifications of the Civil Protection Law in Mexico include now specific mentions to space hazards and space weather phenomena. During the last few years, the UN has promoted international cooperation on Space Weather awareness, studies and monitoring. Internal and external conditions motivated the creation of a Space Weather Service in Mexico (SCIESMEX). The SCIESMEX (www.sciesmex.unam.mx) is operated by the Geophysics Institute at the National Autonomous University of Mexico (UNAM). The UNAM has the experience of operating several critical national services, including the National Seismological Service (SSN); besides that has a well established scientific group with expertise in space physics and solar- terrestrial phenomena. The SCIESMEX is also related with the recent creation of the Mexican Space Agency (AEM). The project combines a network of different ground instruments covering solar, interplanetary, geomagnetic, and ionospheric observations. The SCIESMEX has already in operation computing infrastructure running the web application, a virtual observatory and a high performance computing server to run numerical models. SCIESMEX participates in the International Space Environment Services (ISES) and in the Inter-progamme Coordination Team on Space Weather (ICTSW) of the Word Meteorological Organization (WMO).

  12. Mexican plants and human fertility.

    Science.gov (United States)

    Crabbe, P

    1979-07-01

    Synthetic steroids are obtainable cheaply and in abundance from sapogenins, substances originating from plants of the Discorea family. Some 40 years ago, Russell Marker, an American chemist, discovered this source, which grows abundantly in Mexican jungles and is now exploited and cultivated commercially. Today synthetic steroids prepared from extracts from a wide range of vegetable sources are used in the treatment of rheumatoid arthritis, allergies, inflammatory diseases, sterility, and various heart conditions, and form the basis of modern oral contraceptives. Nevertheless, oral contraceptives in current use are still fairly costly, and women have to be educated in their use. What is needed urgently is a cheaper contraceptive pill with a long-term effect, and research is continuing. For example, scientists from the People's Republic of China have reported significant anti-fertility effects associated with 2 substances, anordin and dinordin, prepared with steroids derived from the sisal plants Agave sisilana and Agave americana. These agents, whose anti-fertility properties have been confirmed by scientists in Sweden and the United States, constitute a new family of contraceptives with the great advantage of having to be taken only once or twice instead of 20 times per month necessary with the ordinary pill. Also from China, scientists have reported the effectiveness of gossypol as an orally administered male contraceptive, although gossypol is not a steroid. It may become, however, a leading candidate for a male contraceptive.

  13. Application of microsatellite markers for breeding and genetic conservation of herds of Pantaneiro sheep

    Directory of Open Access Journals (Sweden)

    Bruno do Amaral Crispim

    2014-11-01

    Conclusions: The results of the statistical parameters indicated that populations of Pantaneiro sheep require special attention on herd management, and it's further necessary to implement breeder exchange programs in order to preserve the genetic variability of these populations. Furthermore, the maintenance of those populations in their typical habitats is rather required to allow different responses from the herds to the interactions between genotype and environment.

  14. Transmission of bovine leukaemia virus within dairy herds by simulation modelling

    OpenAIRE

    Monti, G.E.; Frankena, K.; Jong, de, F.

    2007-01-01

    In Argentina, bovine leukaemia virus (BLV) infection is common in dairy herds. The country currently has a National Voluntary Control Programme but relatively few farms have enrolled. However, there is increased interest from authorities and farmers to implement regional compulsory programmes but there is scarce quantitative information of the transmission of BLV in cattle herds. This information is a prerequisite to develop effective BLV control strategies. Mathematical modelling offers ways...

  15. Factors associated with Neospora caninum serostatus in cattle of 20 specialised Costa Rican dairy herds.

    Science.gov (United States)

    Romero, J J; Perez, E; Dolz, G; Frankena, K

    2002-04-15

    Twenty-five specialised Costa Rican dairy farms (located in the Poás area) were used to determine neosporosis seroprevalence and the association of seropositivity with environmental and management factors. The farms involved were selected intentionally and all of them use VAMPP 5.1 (Veterinary Automated Management and Production Control Programme) as management-information system. Holstein-Friesian, Jersey and crosses between them were the most-frequent breeds in these herds. The number of females per farm varied from 41 to 296. Our cross-sectional study had two phases. In the first phase, we determined the presence or absence of seropositivity at herd level. For the second phase, all females in 20 seropositive farms were bled. Serum samples were tested for antibodies to Neospora caninum using an indirect enzyme-linked immunosorbent assay (ELISA). A questionnaire with factors mentioned in the literature was administered to the farmers. Logistic regression (LR with herd as random effect) was used to assess the relationships of the serostatus at the individual level with characteristics of the cows and environmental factors. In the first phase all herds had >20% seropositive females; therefore, all herds were eligible for the second phase. In the second phase, the overall prevalence was 39.7% (1191/3002), and within-herd prevalences were between 25.0 and 70.5%. Age 3-6 years, parity < or =2 of the dam of the cow, Jersey breed and lack of purposive sampling to diagnose abortive infectious disease were associated with positive serostatus; other management and environmental factors did not show significant associations. The lack of association between management and environmental factors with serostatus might be because all farms were exposed to a considerable number of potential factors. That all herds of this study were seropositive for neosporosis and the within-herd prevalence was considerable raises questions about how far the infection is spread in other dairy

  16. Systematic Epidemiological Investigations of Cases of Senecavirus A in US Swine Breeding Herds.

    Science.gov (United States)

    Baker, K L; Mowrer, C; Canon, A; Linhares, D C L; Rademacher, C; Karriker, L A; Holtkamp, D J

    2017-02-01

    Epidemiological investigations were conducted on a case series of six Senecavirus A (SVA)-affected breeding herds in the United States to determine potential routes of introduction and enhance the swine industry's knowledge of SVA's clinical presentation and spread. Each SVA-affected herd was evaluated using a standard form to ensure that all relevant data were collected. The form was used to guide a detailed discussion about the clinical presentation of SVA and risk events that occurred in the 4 weeks prior to the first observation of clinical signs with the herd veterinarian and farm personnel. Each event was then subjectively assigned a risk level of low, medium or high likelihood for SVA introduction by the investigation team. The clinical presentation of SVA varied by case. All SVA-affected herds (six of six) reported increases in pre-weaning mortality and sow anorexia. Vesicular lesions were observed in four of six herds, and mild-to-moderate neonatal diarrhoea was observed in three of six herds. No gross anatomic or histologic lesions were observed in neonatal pigs that tested positive for SVA via PCR. Multiple potential routes of introduction were identified. Events subjectively rated as high risk for SVA introduction were on-farm employee entry (six of six), carcass disposal (four of six), cull sow removal (three of six) and breeding replacement entry (two of six). Non-swine domestic animals, rodents, other visitors, repairs outside swine barns, feed delivery, weaned pig removal and semen entry were assigned a high risk level in one of six herds. Cases occurred in breeding herds of all sizes with variable biosecurity in both swine dense and swine sparse areas. © 2016 Blackwell Verlag GmbH.

  17. Bovine viral diarrhea virus (BVDV) infection in dairy cattle herds in northeast Thailand.

    Science.gov (United States)

    Nilnont, Theerakul; Aiumlamai, Suneerat; Kanistanont, Kwankate; Inchaisri, Chaidate; Kampa, Jaruwan

    2016-08-01

    Bovine viral diarrhea virus causes a wide range of clinical manifestation with subsequent economic losses in dairy production worldwide. Our study of a population of dairy cattle in Thailand based on 933 bulk tank milk samples from nine public milk collection centers aimed to monitor infective status and to evaluate the effect of the infection in cows as well as to examine the reproductive performance of heifers to provide effective recommendations for disease control in Thailand. The results showed a moderate antibody-positive prevalence in the herd (62.5 %), with the proportion of class-3 herd, actively infected stage, being 17.3 %. Fourteen persistently infected (PI) animals were identified among 1196 young animals from the class-3 herds. Most of the identified PI animals, 11/14, were born in one sub-area where bovine viral diarrhea virus (BVDV) investigation has not been performed to date. With respect to reproductive performance, class-3 herds also showed higher median values of reproductive indices than those of class-0 herds. Cows and heifers in class-3 herds had higher odds ratio of calving interval (CI) and age at first service (AFS) above the median, respectively, compared to class-0 herds (OR = 1.29; P = 0.02 and OR = 1.63; P = 0.02). Our study showed that PI animals were still in the area that was previously studied. Furthermore, a newly studied area had a high prevalence of BVDV infection and the infection affected the reproductive performance of cows and heifers. Although 37.5 % of the population was free of BVDV, the lack of official disease prevention and less awareness of herd biosecurity may have resulted in continuing viral spread and silent economic losses have potentially occurred due to BVDV. We found that BVDV is still circulating in the region and, hence, a national control program is required.

  18. Large scale genomic testing within herd does not affect contribution margin

    DEFF Research Database (Denmark)

    Hjortø, Line; Ettema, Jehan; Sørensen, Anders Christian

    2013-01-01

    A Danish study from 2012 shows that genomic test of all or part of the females in a Holstein herd gives roughly the same economic result as not performing any genomic test at all......A Danish study from 2012 shows that genomic test of all or part of the females in a Holstein herd gives roughly the same economic result as not performing any genomic test at all...

  19. Establishment of serological herd profiles for zoonoses and production diseases in pigs by "meat juice multi-serology".

    Science.gov (United States)

    Meemken, Diana; Tangemann, Anna Helene; Meermeier, Dieter; Gundlach, Susanne; Mischok, Dieter; Greiner, Matthias; Klein, Guenter; Blaha, Thomas

    2014-03-01

    The most important pork-borne zoonotic diseases in humans such as Salmonelloses and Yersinioses cause only latent infections in pigs. Thus, the infection of pigs does not result in apparent or palpable alterations in the pig carcasses. This is the major reason, why the traditional meat inspection with adspection, palpation and incision is not able to control the food safety risks of today. The objective of this paper is to evaluate a set of serological tests, which provides a classification of pig herds into "zoonoses risk categories" as demanded by EU law and into "herd health risk categories" by using meat juice as diagnostic specimen for ELISA tests. Serological data that were obtained by testing meat juice samples from various pig herds were analyzed as proof of the "meat juice multi-serology" concept. For that, at least 60 meat juice samples from 49 pig herds each were taken between September 2010 and March 2011 and tested for antibodies against zoonotic pathogens (Salmonella spp., Trichinella spp., Yersinia enterocolitica and Toxoplasma gondii) and against pathogens causing production diseases (Mycoplasma hyopneumoniae, influenza A virus subtype H1N1, influenza A virus subtype H3N2 and PRRSV). Apparent and true animal prevalence, herd prevalence values and intra-herd seroprevalence values as well as the predictive values for the herd and the animal prevalence values were calculated for each pathogen and each of the 49 randomly selected herds. The herd seroprevalence values (one seropositive sample per herd determined a "positive herd") for Y. enterocolitica, Salmonella spp., T. gondii, M. hyopneumoniae and PRRSV were higher than 80%, respectively, for the influenza A viruses between 60% and 14% and for Trichinella spp. 0%. Although all herds were located in the same area in the Northwest of Germany within a radius of 250 km, the intra-herd seroprevalence values for all tested pathogens, except for Trichinella spp., varied remarkably from herd to herd. In the

  20. Transmission of different variants of PCV2 and viral dynamics in a research facility with pigs mingled from PMWS-affected herds and non-affected herds

    DEFF Research Database (Denmark)

    Dupont, Kitt; Hjulsager, Charlotte Kristiane; Kristensen, C.S.

    2009-01-01

    Post-weaning Multisystemic Wasting Syndrome (PMWS) has been identified in most swine-producing countries worldwide. The disease has resulted in significant health challenges and economic damage to the swine industry. The aim of this study was to determine horizontal transmission of porcine...... circovirus type 2 (PCV2) and to examine viral dynamics in pigs in a controlled PMWS transmission study. In the study pigs from PMWS-affected herds and non-affected herds were permitted to have close contact (same pen), nose-to-nose contact (to pigs in neighbouring pens) or no physical contact (pen across...

  1. Neospora caninum in Estonian dairy herds in relation to herd size, reproduction parameters, bovine virus diarrhoea virus, and bovine herpes virus 1.

    Science.gov (United States)

    Lassen, Brian; Orro, Toomas; Aleksejev, Annely; Raaperi, Kerli; Järvis, Toivo; Viltrop, Arvo

    2012-11-23

    Cows infected with the tissue parasite Neospora caninum (Nc) are more likely to abort or give birth to calves with neurological disorders. The known infection routes are transplacentally and by consumption of oocysts shed by the definitive host, the dog. It has been hypothesised, that dormant stages of persistent Nc infection may be reactivated by immunosuppression mechanisms such as pathogenic invasions as bovine herpes virus 1 (BHV1) and bovine virus diarrhoea virus (BVDV). The study was set to give the first prevalence data on Nc from Estonian dairy herds in both animal as well as herd level. In addition, association between herd size and Nc, and association of Nc with abortion incidence (Ab), stillbirth incidence (Sb), insemination index (II), and calving interval (CaI) in the presence of BHV1 and BVDV was studied. Blood samples from 1973 animals from 100 herds were collected in 2006-2008, and 320 bulk tank milk (BTM) samples were collected in 2007. Antibodies against Nc was found in 2.5 ± 0.4% (95% CI) of the animals and at least one positive animal was found in 37.0 ± 4.7% (95% CI) of the herds. In addition, Nc antibodies were detected in 16.3 ± 2.0% (95% CI) of the tested BTM. Large herds (≥ 200 animals) were less likely to have seropositive animals for Nc. Logistic regression models showed that herds with more than one animal seropositive for Nc had significantly higher odds ratio of abortion incidence (OR: 11.92, 1.18-120.18 95% CI, p=0.036) and tendency of having more stillbirths (OR: 5.52, 0.87-35.02 95% CI, p=0.07). On the other hand one Nc seropostive cow in the herd was associated with lower odds ratio (OR: 0.22, 0.05-0.91 95% CI, p=0.04) of higher calving intervals. Estonian prevalence results reflect observations in the region. No evidence was found of the pathogens were affecting fertility variables through interactions but independently BHV1 and Nc had an impact on the abortion.

  2. The prevalence of swine enteropathogens in Brazilian grower and finish herds.

    Science.gov (United States)

    Viott, A M; Lage, A P; Cruz, E C C; Guedes, R M C

    2013-05-17

    Diarrhoea among growing and finishing pigs is an important problem in many herds. The prevalence of L. intracellularis, B. pilosicoli, B. hyodysenteriae, Salmonella spp., enterotoxigenic E. coli, Trichuris suis and the occurrence of mixed infection were investigated. Fecal samples for forty-six herds with diarrhea or a history of diarrhea were randomly collected in Minas Gerais state, Brazil. The enteric pathogens were detected by culture (E. coli and Salmonella sp.), PCR (L. intracellularis and Brachyspira spp.) and eggs counts (T. suis). The overall herd prevalence of L. intracellularis, Salmonella enterica serotype Typhimurium and enterotoxigenic E. coli were 19.56%, 6.52%, 10.86% respectively. Mixed infection was diagnosed in 30.43% of herds, and L. intracellularis and Salmonella enterica serotype Typhimurium are main pathogens association (10.87%). B. pilosicoli was diagnosed only in two herds, always associated with mixed infections. B. hyodysenteriae and T. suis were not demonstrated in any sample. These pathogens have been reported world-wide but studies regarding epidemiology in Brazil are few. This study contributes to establish of prevention programs for the control enteropathogens in grower finish herds in Brazil.

  3. The prevalence of swine enteropathogens in Brazilian grower and finish herds

    Directory of Open Access Journals (Sweden)

    A.M. Viott

    2013-01-01

    Full Text Available Diarrhoea among growing and finishing pigs is an important problem in many herds. The prevalence of L. intracellularis, B. pilosicoli, B. hyodysenteriae, Salmonella spp., enterotoxigenic E. coli, Trichuris suis and the occurrence of mixed infection were investigated. Fecal samples for forty-six herds with diarrhea or a history of diarrhea were randomly collected in Minas Gerais state, Brazil. The enteric pathogens were detected by culture (E. coli and Salmonella sp., PCR (L. intracellularis and Brachyspira spp. and eggs counts (T. suis. The overall herd prevalence of L. intracellularis, Salmonella enterica serotype Typhimurium and enterotoxigenic E. coli were 19.56%, 6.52%, 10.86% respectively. Mixed infection was diagnosed in 30.43% of herds, and L. intracellularis and Salmonella enterica serotype Typhimurium are main pathogens association (10.87%. B. pilosicoli was diagnosed only in two herds, always associated with mixed infections. B. hyodysenteriae and T. suis were not demonstrated in any sample. These pathogens have been reported world-wide but studies regarding epidemiology in Brazil are few. This study contributes to establish of prevention programs for the control enteropathogens in grower finish herds in Brazil.

  4. Herd-Level Risk Factors for Bovine Tuberculosis: A Literature Review

    Directory of Open Access Journals (Sweden)

    Robin A. Skuce

    2012-01-01

    Full Text Available Bovine tuberculosis (TB, caused by Mycobacterium bovis, is one of the most challenging endemic diseases currently facing government, the veterinary profession, and the farming industry in the United Kingdom and Ireland and in several other countries. The disease has a notoriously complex epidemiology; the scientific evidence supports both cattle-cattle and wildlife-cattle transmission routes. To produce more effective ways of reducing such transmission, it is important to understand those risk factors which influence the presence or absence of bovine TB in cattle herds. Here we review the literature on herd-level risk factor studies. Whilst risk factors operate at different scales and may vary across regions, epidemiological studies have identified a number of risk factors associated with bovine TB herd breakdowns, including the purchase of cattle, the occurrence of bovine TB in contiguous herds, and/or the surrounding area as well as herd size. Other factors identified in some studies include farm and herd management practices, such as, the spreading of slurry, the use of certain housing types, farms having multiple premises, and the use of silage clamps. In general, the most consistently identified risk factors are biologically plausible and consistent with known transmission routes involving cattle-cattle and wildlife-cattle pathways.

  5. Evaluating the reproductive performance of British beef and dairy herds using national cattle movement records.

    Science.gov (United States)

    Gates, M C

    2013-11-23

    National cattle movement databases provide a valuable opportunity to monitor the reproductive performance of breeding cattle on an industry-wide scale. In this analysis, records from the Cattle Tracing System database were used to derive key measures of reproductive efficiency for British beef and dairy herds, including calving spread, age at first calving, calving interval, culling rate and calf mortality rate. At the animal level, only 8.5 per cent of beef heifers and 6.9 per cent of dairy heifers calved by the target age of 24 months. The average calving interval was 394 days for beef dams (median: 371) and 426 days for dairy dams (median: 400). Differences in performance were noted between cattle breeds. An estimated 43.9 per cent calves born in dairy herds were crossbreed beef animals, which may limit the availability of replacement dairy heifers. At the herd level, calving spread and calf mortality rates increased with herd size, while average age at first calving, calving interval, and crossbreeding generally decreased with herd size. Dam age, calving month, breed and twinning were significant risk factors for culling and calf mortality at the animal level. Wide variation in performance between individual herds highlights the potential for improving the efficiency of British cattle production.

  6. Bulk milk ELISA and the diagnosis of parasite infections in dairy herds: a review.

    Science.gov (United States)

    Sekiya, Mary; Zintl, Annetta; Doherty, Michael L

    2013-07-25

    The bulk milk enzyme-linked immune sorbent assay (ELISA) is a rapid and inexpensive method of assessing herd exposure to pathogens that is increasingly being used for the diagnosis of parasite infections in dairy herds. In this paper, with the dairy herd health veterinarian in mind, we review the principles of the assay and the recent literature on the potential role of bulk milk ELISA for the diagnosis of ostertagiosis, fasciolosis, parasitic bronchitis due to cattle lung worm and neosporosis. It is generally accepted that assay results reflect exposure to the parasite rather than the presence of active infection. Bulk milk ELISA can be a useful tool for the veterinary practitioner as a component of a herd health monitoring programme or in the context of a herd health investigation. It can also play a role in regional or national surveillance programmes. However, the results need to be interpreted within the context of the herd-specific health management, the milk production pattern and the parasite life cycle.

  7. Temporal trends in reproductive performance in Irish dairy herds and associated risk factors

    Directory of Open Access Journals (Sweden)

    Mee John F

    2004-03-01

    Full Text Available Irish dairy herd fertility has been declining since the 1980s. The extent, nature and causes of this decline in fertility and the current status of Irish dairy herd fertility were described. An increase in calving interval of approximately one day per year has been recorded. The principal components of this trend have been an increased incidence of postpartum endocrinopathies, reduced expression of oestrus and a fall in conception rate. Both submission rate and calving-to-service interval have increased slightly over time. Significant risk factors associated with these trends have been strain substitution within the Holstein-Friesian breed and single trait selection for milk production. Critically, these changes have been reflected in loss of body condition. Contributory factors included increased herd size and possibly increased use of DIYAI. The most recent Irish study showed that 48% of cows conceived to first service and 14% of cows were not pregnant at the end of the industry-average 15-week spring breeding season. However, the top quartile of herds achieved a first-service conception rate of 59%, illustrating the wide variation between herds. These phenotypic trends were attributed to both genetic and environmental factors and their interactions. Recent Irish dairy herd fertility performance falls short of the targets set for seasonal compact calving.

  8. [Echinoderms (Echinodermata) of the Mexican Caribbean].

    Science.gov (United States)

    Laguarda-Figueras, Alfredo; Solis-Marín, Francisco A; Durán-González, Alicia; Ahearn, Cynthia Gust; Buitrón Sánchez, Blanca Estela; Torres-Vega, Juan

    2005-12-01

    A systematic list of the echinoderms of the Mexican Caribbean based on museum specimens of the Colección Nacional de Equinodermos, Instituto de Ciencias del Mar y Limnología, Universidad Nacional Autónoma de México and the National Museum of Natural History, Smithsonian Institution, Washington, D.C. is presented. This list reveals an important echinoderm biodiversity in the Mexican Caribbean, where five of the six echinoderm classes are represented. A total of 178 echinoderm species is recorded, distributed in 113 genera, 51 families and 22 orders. 30 new records for the Mexican Caribbean are presents: Crínoidea (three), Asteroidea (two), Ophiuroidea (eleven), Echinoidea (one), Holothuroidea (thirteen).

  9. Mexican petroleum and US national security

    Energy Technology Data Exchange (ETDEWEB)

    Fagen, R.R.

    US vulnerability to energy supplies is reviewed in terms of action taken by the Organizaion of Petroleum Exporting Countries (OPEC) during the 1970s and the outlook for supply and price disruptions in the 1980s. The US position is then related to the Mexican petroleum boom and the benefits that increasing exports from a non-OPEC country like Mexico can have on world oil trade. US political and security interests will encourage a rapid increase in Mexican production, and the US will be concerned with how Mexico develops its relationships with the US and with other oil-producing countries. Changing economic and social relationships are inevitable and could lead to serioUS political unrest over questions of equity and immigrations. The difficulty of articulating US security interests without interfering in Mexican domestic affairs will require careful diplomacy.

  10. Chemical constituents of red Mexican propolis.

    Science.gov (United States)

    Lotti, Cinzia; Campo Fernandez, Mercedes; Piccinelli, Anna Lisa; Cuesta-Rubio, Osmany; Márquez Hernández, Ingrid; Rastrelli, Luca

    2010-02-24

    Chemical investigation of a red-type Mexican propolis sample has led to the isolation of three new compounds, 1-(3',4'-dihydroxy-2'-methoxyphenyl)-3-(phenyl)propane (1), (Z)-1-(2'-methoxy-4',5'-dihydroxyphenyl)-2-(3-phenyl)propene (2) and 3-hydroxy-5,6-dimethoxyflavan (3), together with seven known flavanones, isoflavans, and pterocarpans. Structural determination, was accomplished by spectroscopic analysis, particularly 2D NMR and ESI-MS/MS techniques. The present study appears to be the first report on the occurrence of isoflavonoids in Mexican propolis. In addition, the presence of compounds with a 1,3-diarylpropane and 1,3-diarylpropene carbon skeleton were found for the first time in propolis. Isolated compounds 1-10 indicated the possible relation between red Mexican propolis and the genus Dalbergia.

  11. Disease Recording Systems and Herd Health Schemes for Production Diseases

    Directory of Open Access Journals (Sweden)

    Østerås O

    2001-03-01

    Full Text Available Disease recording of cattle is compulsory in Sweden and Norway. Sweden and Denmark also have mandatory disease recording for swine, whereas Finland and Norway only have compulsory recording of infectious diseases. Both compulsory and voluntary systems are databased, the first ones developed in the 1970's. Disease recording at pig slaughtering is somewhat older. The veterinary practitioner, and often also the farmer, can report treated cases as well as fertility disturbances to the systems. Disease recording at slaughter is carried out by veterinarians and inspection officers. The databases are handled by the veterinary authorities or the agricultural organisations in each country. Costs are defrayed by the authorities and/or the agricultural industry. The farmers receive periodic reports. Data are stored for three to ten years, often longer. Affiliation to animal health schemes for cattle or swine is voluntary. In Sweden and Denmark (cattle they are run within the scope of government regulations. Affiliation to animal health programmes may also be demanded by organisations within the agricultural industry. These organisations are also responsible for the administration of the programmes. Costs to take part in herd health schemes are covered by the farmers themselves. In certain cases, grants are received from agricultural organisations, authorities, or the European Union. Recording of diseases and the format of animal health schemes in the Nordic countries are described here in order to illustrate the possibilities to compare data between countries.

  12. Population viscosity suppresses disease emergence by preserving local herd immunity.

    Science.gov (United States)

    Reluga, Timothy C; Shim, Eunha

    2014-12-01

    Animal reservoirs for infectious diseases pose ongoing risks to human populations. In this theory of zoonoses, the introduction event that starts an epidemic is assumed to be independent of all preceding events. However, introductions are often concentrated in communities that bridge the ecological interfaces between reservoirs and the general population. In this paper, we explore how the risks of disease emergence are altered by the aggregation of introduction events within bridge communities. In viscous bridge communities, repeated introductions can elevate the local prevalence of immunity. This local herd immunity can form a barrier reducing the opportunities for disease emergence. In some situations, reducing exposure rates counterintuitively increases the emergence hazards because of off-setting reductions in local immunity. Increases in population mixing can also increase emergence hazards, even when average contact rates are conserved. Our theory of bridge communities may help guide prevention and explain historical emergence events, where disruption of stable economic, political or demographic processes reduced population viscosity at ecological interfaces.

  13. Herd immunity to Newcastle disease virus in poultry by vaccination.

    Science.gov (United States)

    van Boven, Michiel; Bouma, Annemarie; Fabri, Teun H F; Katsma, Elly; Hartog, Leo; Koch, Guus

    2008-02-01

    Newcastle disease is an economically important disease of poultry for which vaccination is applied as a preventive measure in many countries. Nevertheless, outbreaks have been reported in vaccinated populations. This suggests that either the vaccination coverage level is too low or that vaccination does not provide perfect immunity, allowing the virus to spread in partially vaccinated populations. Here we study the requirements of an epidemiologically effective vaccination program against Newcastle disease in poultry, based on data from experimental transmission studies. The transmission studies indicate that vaccinated birds with low or undetectable antibody titres may be protected against disease and mortality but that infection and transmission may still occur. In fact, our quantitative analyses show that Newcastle disease virus is highly transmissible in poultry with low antibody titres. As a consequence, herd immunity can only be achieved if a high proportion of birds (>85%) have a high antibody titre (log(2) haemagglutination inhibition titre > or =3) after vaccination. We discuss the implications for the control of Newcastle disease in poultry by vaccination.

  14. [Multiresistant Brachyspira hyodysenteriae in a Dutch sow herd].

    Science.gov (United States)

    Duinhof, T F; Dierikx, C M; Koene, M G J; van Bergen, M A P; Mevius, D J; Veldman, K T; van Beers-Schreurs, H M G; de Winne, R T J A

    This case study describes the isolation ofa multiresistant strain ofBrachyspira hyodysenteriae in April 2007 in a Dutch sow herd with recurrent diarrhoea. Examination of faecal samples taken from 7-month-old breeding gilts with diarrhoea revealed the presence of resistance against tiamulin, lincomycin, tylosin, doxycycline, and tylvalosin (the active substance in Aivlosin) in four of five samples. Tiamulin resistance has not been reported in The Netherlands before. The repeated use of tiamulin on the affected farm was assumed to be the main cause of the development of resistance to the drug. The farmer was advised to adopt a medication strategy and to implement management practices that would prevent an ongoing cycle of infection on the farm. It is important that the Dutch swine industry appreciates that tiamulin-resistant strains of B. hyodysenteriae may be found on other farms as well. The appropriate and prudent use of antibiotics is essential in order to prevent the development of resistance against the last option left to cure B. hyodysenteriae infections: valnemulin.

  15. Financial aspects of veterinary herd health management programmes.

    Science.gov (United States)

    Ifende, V I; Derks, M; Hooijer, G A; Hogeveen, H

    2014-09-01

    Veterinary herd health management (VHHM) programmes have been shown to be economically effective in the past. However, no current information is available on costs and benefits of these programmes. This study compared economics and farm performance between participants and non-participants in VHHM programmes in 1013 dairy farms with over 40 cows. Milk Production Registration (MPR) data and a questionnaire concerning VHHM were used. Based on the level of participation in VHHM (as indicated in the questionnaire), costs of the programmes were calculated using a normative model. The economic value of the production effects was similarly calculated using normative modelling based on MPR data. Participants in VHHM had a better performance with regard to production, but not with regard to reproduction. Over 90 per cent of the VHHM participants were visited at least once every six weeks and most participants discussed at least three topics. In most farms, the veterinarian did the pregnancy checks as part of the VHHM programmes. There was a benefit to cost ratio of about five per cow per year for VHHM participants, and a mean difference in net returns of €30 per cow per year after adjusting for the cost of the programme. This portrays that participation in a VHHM programme is cost-efficient. There is, however, much unexplained variation in the net returns, possibly due to diverse approaches by veterinarians towards VHHM or by other factors not included in this analysis, like nutritional quality or management abilities of the farmer.

  16. Prevalence of Pathogens Causing Subclinical Mastitis in Argentinean Dairy Herds

    Directory of Open Access Journals (Sweden)

    Silvana Andrea Dieser

    2014-01-01

    Full Text Available The objective of this study was to investigate the prevalence of different mastitis pathogens in Argentinean dairy farms. Composite milk samples were collected of 2296 cows from 51 randomly selected herds in Córdoba, Argentina. Somatic cell count was determined in all samples and bacterial examination of the milk samples with a SCC exceeding 200,000 cells/mL was performed. About 54%of cows were diagnosed with subclinical mastitis (SCC ≥200,000/mL. Bacteria were isolated in 83.1% of milk samples subjected to bacteriological analysis. The most frequently isolated pathogen was coagulase-negative staphylococci (CNS (52.1%, followed by Staphylococcus aureus (21.3%, Corynebacterium spp. (5.2%, Streptococcus agalactiae (4.4% and Streptococcus dysgalactiae (4.4%. This study demonstrates that among the major pathogens isolated, the contagious bacteria caused most of the subclinical infections of dairy cows in Cordoba, Argentina. Moreover, CNS was the most relevant group of minor pathogens causing subclinical mastitis.

  17. Polymorphisms in the leptin gene promoter in Brazilian beef herds.

    Science.gov (United States)

    Guimarães, R C; Azevedo, J S N; Corrêa, S C; Campelo, J E G; Barbosa, E M; Gonçalves, E C; Silva Filho, E

    2016-12-02

    Brazil is the world's largest producer of beef cattle; however, the quality of its herds needs to be improved. The use of molecular markers as auxiliary tools in selecting animals for reproduction with high pattern for beef production would significantly improve the quality of the final beef product in Brazil. The leptin gene has been demonstrated to be an excellent candidate gene for bovine breeding. The objective of this study was to sequence and compare the leptin gene promoter of Brazil's important cattle breeds in order to identify polymorphisms in it. Blood samples of the Nellore, Guzerat, Tabapuã, and Senepol breeds were collected for genomic DNA extraction. The genomic DNA was used as a template for polymerase chain reaction (PCR) to amplify a 1575-bp fragment, which in turn was sequenced, aligned, and compared between animals of different breeds. Twenty-three single nucleotide polymorphic sites, including transitions and transversions, were detected at positions -1457, -1452, -1446, -1397, -1392, -1361, -1238, -963,-901, -578, -516, -483, -478, -470, -432, -430, -292, -282, -272, -211, -202, -170, and -147. Additionally, two insertion sites at positions -680 and -416 and two deletion sites at positions -1255 and -1059 were detected. As the promoter region of the leptin gene has been demonstrated to vary among breeds, these variations must be tested for their use as potential molecular markers for artificial selection of animals for enhanced beef production in different systems of bovine production in Brazil.

  18. Milk iodine residues in herds practicing iodophor premilking teat disinfection.

    Science.gov (United States)

    Galton, D M; Petersson, L G; Erb, H N

    1986-01-01

    The objective was to determine effects of different concentrations of iodophor teat dips on milk iodine residues, when teat dips were used both premilking and postmilking. Eighty cows in each of seven herds were assigned to one of four treatments. Each treatment received postmilking teat dip at .1 or 1% iodophor concentration. Two groups received no premilking dip, and the other two groups received premilking teat dip at the same concentration as the postmilking teat dip. Premilking teat dipping was followed by manual drying of teats. Noniodophor postmilking dips and no premilking inodophor udder sanitizers were used during an 8-d adjustment period. Milk was collected for milk iodine determination from each cow from weigh jars or milk meters at p.m. milkings during the last 3 d of the adjustment period and d 4, 6, and 8 of the treatment period. Premilking and postmilking teat dipping with .1% iodophor dip did not significantly increase milk iodine residue above postmilking teat dipping with .1% iodophor dip alone. However, 1% iodophor postmilking teat dip significantly increased milk iodine residue over use of .1% iodophor dip used as a premilking and postmilking teat dip. Adding a 1% iodophor premilking teat dip significantly increased iodine residues.

  19. Herd management and social variables associated with bulk tank somatic cell count in dairy herds in the eastern United States.

    Science.gov (United States)

    Schewe, R L; Kayitsinga, J; Contreras, G A; Odom, C; Coats, W A; Durst, P; Hovingh, E P; Martinez, R O; Mobley, R; Moore, S; Erskine, R J

    2015-11-01

    The ability to reduce somatic cell counts (SCC) and improve milk quality depends on the effective and consistent application of established mastitis control practices. The US dairy industry continues to rely more on nonfamily labor to perform critical tasks to maintain milk quality. Thus, it is important to understand dairy producer attitudes and beliefs relative to management practices, as well as employee performance, to advance milk quality within the changing structure of the dairy industry. To assess the adoption rate of mastitis control practices in United States dairy herds, as well as assess social variables, including attitudes toward employees relative to mastitis control, a survey was sent to 1,700 dairy farms in Michigan, Pennsylvania, and Florida in January and February of 2013. The survey included questions related to 7 major areas: sociodemographics and farm characteristics, milking proficiency, milking systems, cow environment, infected cow monitoring and treatment, farm labor, and attitudes toward mastitis and related antimicrobial use. The overall response rate was 41% (21% in Florida, 39% in Michigan, and 45% in Pennsylvania). Herd size ranged from 9 to 5,800 cows. Self-reported 3-mo geometric mean bulk tank SCC (BTSCC) for all states was 194,000 cells/mL. Multivariate analysis determined that proven mastitis control practices such as the use of internal teat sealants and blanket dry cow therapy, and not using water during udder preparation before milking, were associated with lower BTSCC. Additionally, farmer and manager beliefs and attitudes, including the perception of mastitis problems and the threshold of concern if BTSCC is above 300,000 cells/mL, were associated with BTSCC. Ensuring strict compliance with milking protocols, giving employees a financial or other penalty if BTSCC increased, and a perceived importance of reducing labor costs were negatively associated with BTSCC in farms with nonfamily employees. These findings highlight the

  20. Employers mexican migrants in the United States

    Directory of Open Access Journals (Sweden)

    Eduardo Fernández Guzmán

    2013-09-01

    Full Text Available You might think that by definition the migrant labor plays in less profitable niches and meager social mobility. However, a large group of migrants in different economically developed countries have successfully launched businesses of diverse nature and volume. This is why entrepreneurship of migrants is an issue that has received increasing attention in recent years. Compared to other immigrant groups in the United States, Mexicans show low levels of entrepreneurial activity. The aim of this paper is to, through a general literature review of official statistical data, a preliminary analysis of mexican migrant entrepreneurship in the United States, that is to say in recent years has been growing in importance.

  1. Chemical-reaction model for Mexican wave

    Science.gov (United States)

    Nagatani, Takashi

    2003-05-01

    We present a chemical-reaction model to describe the Mexican wave ( La Ola) in football stadia. The spectator's action is described in terms of chemical reactions. The model is governed by three reaction rates k 1, k 2, and k3. We study the nonlinear waves on one- and two-dimensional lattices. The Mexican wave is formulated as a clockwise forwardly propagating wave. Waves are growing or disappear, depending on the values of reaction rates. In the specific case of k1= k2= k3=1, the nonlinear-wave equation produces a propagating pulse like soliton.

  2. Narcocultura: A Threat to Mexican National Security?

    Science.gov (United States)

    2012-12-01

    Tuckman, “Mexican ‘Saint Death’ cult members protest at destruction of shrines,” The Guardian , April 10, 2009, http://www.guardian.co.uk/world/2009/apr...derribado aviones que nos han caído al campo a quemarnos los plantíos donde sale el polvo blanco con bazucas y metrallas los hemos mandado al Diablo ...www.musica.com/letras.asp?letra=886612. Tuckman, Jo. “Mexican ‘Saint Death’ cult members protest at destruction of shrines.” The Guardian . April 10

  3. Mexican oil industry: Shifting to difficult oil

    Energy Technology Data Exchange (ETDEWEB)

    Bazan G., Gerardo; Gonzalez, Cristobal J.

    2010-09-15

    Mexico has stepped into an important transition of declining oil fields and new challenging oil projects. The aim of this paper is to show a new perspective of the oil resources that have been exploited throughout the Mexican territory, as well as the remaining resources yet to be exploited. We have developed a resources/production-costs chart that illustrates the historical and future development of the Mexican oil industry, showing the shift that the industry will face in the coming years; this chart was taken from a model already in use by the most prestige energy agencies in the world.

  4. Herd risk factors associated with sero-prevalence of Maedi-Visna in the Manitoba sheep population.

    Science.gov (United States)

    Shuaib, Muhammad; Green, Chris; Rashid, Mamoon; Duizer, Glen; Whiting, Terry L

    2010-04-01

    Disease associated with Maedi-Visna infection results in substantial economic losses in affected sheep producing areas of the world. A survey was conducted to estimate herd and individual seroprevalence in the province of Manitoba and evaluate risk factors for seropositive herds. Of 2207 sheep sampled from 77 selected sheep flocks, the animal level seroprevalence was 2.47% and herd level seroprevalence was 25.10%. The herd-level factors of presence of clinical skin disease, herd size of > 70, history of musculoskeletal/lameness abnormalities, and the purchase of new stock (> 50) in the last 1 to 5 y, showed significant associations with seropositive herd status. The study documented a remarkable stability of low seroprevalence in the province over a 20-year period in the absence of a systematic disease control program.

  5. Prevalence and molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) in organic pig herds in The Netherlands.

    Science.gov (United States)

    van de Vijver, L P L; Tulinski, P; Bondt, N; Mevius, D; Verwer, C

    2014-08-01

    The prevalence of the methicillin-resistant Staphylococcus aureus (MRSA) among conventional pig herds in the Netherlands is high (around 71%). Nevertheless, information about the prevalence of MRSA among organic pig herds is lacking. Here, we report a study on 24 of the 49 organic pig herds in the Netherlands. The prevalence of MRSA positive herds showed to be 21%. The genetic characteristics of the MRSA isolates were similar to MRSA CC398 described in conventional pigs except one exceptional HA-MRSA CC30 found in one herd, which was presumably caused by human to animal transmission. This resulted in a prevalence of MRSA CC398 in the organic herds of 16.7%.

  6. Predictors of Routine Medical Care Use among Mexican Immigrants/Mexican-Americans Varying in Legal Status

    OpenAIRE

    Garcini, Luz M.; Ayala, Guadalupe X; Molina, Marisa; Quintanar, Elena; Johansen, Christopher; Hector, Richard

    2015-01-01

    Background: Immigration has been the focus of intense political debate, with a recurrent theme being the use of public services, including healthcare. Although Latinos are the largest and fastest growing ethnic group in the United States (U.S.), evidence suggests they underutilize healthcare, with Mexican Immigrants and Mexican Americans (MI-MA) living on the U.S.-Mexico border exhibiting the greatest disparities. Objective: This study explored the association of predisposing, enabling and ne...

  7. Clinical and laboratory studies on herds affected with postweaning multisystemic wasting syndrome in Denmark, France, Spain, and Sweden: Disease progression and a proposal for herd case definition

    DEFF Research Database (Denmark)

    Grau-Roma, L.; Baekbo, P.; Rose, N.

    2012-01-01

    Objectives: To propose and evaluate a protocol to establish a diagnosis of postweaning multisystemic wasting syndrome (PMWS) at herd level. Materials and methods: The data used included both laboratory data from previous epidemiological studies carried out in Italy, Denmark, and Spain and original...

  8. Milk quality assurance for paratuberculosis: simulation of within-herd infection dynamics and economicsof within-herd infection dynamics and economics

    NARCIS (Netherlands)

    Weber, M.F.; Nielen, M.; Velthuis, A.G.J.; Roermund, van H.J.W.

    2008-01-01

    bulk milk quality assurance programme for Mycobacterium avium subsp. paratuberculosis (Map) in dairy herds was simulated with a stochastic simulation model (JohneSSim). The aim of this study was to evaluate the epidemiological and economic effects of preventive management measures and various test s

  9. Clinical and laboratory studies on herds affected with postweaning multisystemic wasting syndrome in Denmark, France, Spain, and Sweden: Disease progression and a proposal for herd case definition

    DEFF Research Database (Denmark)

    Grau-Roma, L.; Baekbo, P.; Rose, N.

    2012-01-01

    Objectives: To propose and evaluate a protocol to establish a diagnosis of postweaning multisystemic wasting syndrome (PMWS) at herd level. Materials and methods: The data used included both laboratory data from previous epidemiological studies carried out in Italy, Denmark, and Spain and original...

  10. Metabolic profiles in five high-producing Swedish dairy herds with a history of abomasal displacement and ketosis

    Directory of Open Access Journals (Sweden)

    Stengärde Lena

    2008-08-01

    Full Text Available Abstract Background Body condition score and blood profiles have been used to monitor management and herd health in dairy cows. The aim of this study was to examine BCS and extended metabolic profiles, reflecting both energy metabolism and liver status around calving in high-producing herds with a high incidence of abomasal displacement and ketosis and to evaluate if such profiles can be used at herd level to pinpoint specific herd problems. Methods Body condition score and metabolic profiles around calving in five high-producing herds with high incidences of abomasal displacement and ketosis were assessed using linear mixed models (94 cows, 326 examinations. Cows were examined and blood sampled every three weeks from four weeks ante partum (ap to nine weeks postpartum (pp. Blood parameters studied were glucose, fructosamine, non-esterified fatty acids (NEFA, insulin, β-hydroxybutyrate, aspartate aminotransferase, glutamate dehydrogenase, haptoglobin and cholesterol. Results All herds had overconditioned dry cows that lost body condition substantially the first 4–6 weeks pp. Two herds had elevated levels of NEFA ap and three herds had elevated levels pp. One herd had low levels of insulin ap and low levels of cholesterol pp. Haptoglobin was detected pp in all herds and its usefulness is discussed. Conclusion NEFA was the parameter that most closely reflected the body condition losses while these losses were not seen in glucose and fructosamine levels. Insulin and cholesterol were potentially useful in herd profiles but need further investigation. Increased glutamate dehydrogenase suggested liver cell damage in all herds.

  11. Facing the limit of resilience: perceptions of climate change among reindeer herding Sami in Sweden

    Directory of Open Access Journals (Sweden)

    Maria Furberg

    2011-10-01

    Full Text Available The Arctic area is a part of the globe where the increase in global temperature has had the earliest noticeable effect and indigenous peoples, including the Swedish reindeer herding Sami, are amongst the first to be affected by these changes.To explore the experiences and perceptions of climate change among Swedish reindeer herding Sami.In-depth interviews with 14 Swedish reindeer herding Sami were performed, with purposive sampling. The interviews focused on the herders experiences of climate change, observed consequences and thoughts about this. The interviews were analysed using content analysis. One core theme emerged from the interviews: facing the limit of resilience. Swedish reindeer-herding Sami perceive climate change as yet another stressor in their daily struggle. They have experienced severe and more rapidly shifting, unstable weather with associated changes in vegetation and alterations in the freeze–thaw cycle, all of which affect reindeer herding. The forecasts about climate change from authorities and scientists have contributed to stress and anxiety. Other societal developments have lead to decreased flexibility that obstructs adaptation. Some adaptive strategies are discordant with the traditional life of reindeer herding, and there is a fear among the Sami of being the last generation practising traditional reindeer herding.The study illustrates the vulnerable situation of the reindeer herders and that climate change impact may have serious consequences for the trade and their overall way of life. Decision makers on all levels, both in Sweden and internationally, need improved insights into these complex issues to be able to make adequate decisions about adaptive climate change strategies.

  12. Streptococcus agalactiae in the environment of bovine dairy herds--rewriting the textbooks?

    Science.gov (United States)

    Jørgensen, H J; Nordstoga, A B; Sviland, S; Zadoks, R N; Sølverød, L; Kvitle, B; Mørk, T

    2016-02-29

    Many free-stall bovine dairy herds in Norway fail to eradicate Streptococcus agalactiae despite long-term control measures. In a longitudinal study of 4 free-stall herds with automatic milking systems (AMS), milk and extramammary sites were sampled 4 times with 1-2 month intervals. Composite milk, rectal- and vaginal swabs were collected from dairy cows; rectal swabs from heifers and young stock; rectal- and tonsillar swabs from calves; and environmental swabs from the AMS, the floors, cow beds, watering and feeding equipment. A cross sectional study of 37 herds was also conducted, with 1 visit for environmental sampling. Fifteen of the herds were known to be infected with S. agalactiae while the remaining 22 had not had evidence of S. agalactiae mastitis in the preceding 2 years. All samples were cultured for S. agalactiae, and selected isolates (n=54) from positive herds were genotyped by Multi Locus Sequence Typing (MLST). Results show that the bovine gastrointestinal tract and the dairy cow environment are reservoirs of S. agalactiae, and point to the existence of 2 transmission cycles; a contagious transmission cycle via the milking machine and an oro-fecal transmission cycle, with drinking water as the most likely vehicle for transmission. Ten sequence types were identified, and results suggest that strains differ in their ability to survive in the environment and transmit within dairy herds. Measures to eradicate S. agalactiae from bovine dairy herds should take into account the extra-mammary reservoirs and the potential for environmental transmission of this supposedly exclusively contagious pathogen.

  13. A stochastic model simulating the feeding-health-production complex in a dairy herd.

    Science.gov (United States)

    Ostergaard, S; Sørensen, J T; Kristensen, A R

    2000-04-01

    A dynamic, stochastic, and mechanistic Monte Carlo model, simulating a dairy herd with focus on the feeding-health-production complex is presented. By specifying biological parameters at cow level and a management strategy at herd level, the model can simulate the technical and economic consequences of scenarios at herd level. The representation of the feeding-health-production complex is aimed to be sufficiently detailed, to include relationships likely to cause significant herd effects, and to be sufficiently simple to enable a feasible parameterization of the model and interpretation of the results from the model. Consequently, diseases are defined as four disease types: two metabolic disease types, an udder disease type, and a reproductive disease type. Risk factors for the diseases were defined as parity, yield capacity, disease recurrence, disease interrelationships, lactation stage, and season. Direct effects of the diseases were defined according to milk yield, feed intake, feed utilization, conception, culling, involuntary removal, and death. Scenarios differing in base risks of milk fever and ketosis, heat detection rate, and culling strategy were simulated for describing the model behavior. Annual milk yield per cow was decreased by increased risk of ketosis and by increased risk of milk fever, even though no direct effect of milk fever on milk yield was modeled at the cow level. The indirect effect from milk fever is a consequence of increased replacement rate (relatively lower milk yield from younger cows). By ignoring the history of milk fever in insemination and replacement decisions, a significantly reduced net income per cow was found in some herds. We concluded that important benefits from using such a herd model are the capability of accounting for herd management factors and the advantage of avoiding to double count the indirect effects from disease, such as increased risk of other diseases, poorer reproduction results, and increased risk of

  14. Neospora caninum in beef herds in New South Wales, Australia. 2: analysis of risk factors.

    Science.gov (United States)

    Moloney, B J; Heuer, C; Kirkland, P D

    2017-04-01

    To determine the influence of farm-level and animal-level factors on the seroprevalence of antibodies to Neospora caninum and associations between seropositivity and reproductive outcomes. A questionnaire for a cross-sectional survey was posted to the 63 properties with a herd size ≥50 beef breeding cows that had participated in a previous seroprevalence study. Correspondence analysis, which does not appear to have been used previously in any Australian studies of livestock diseases, was used in conjunction with logistic regression to analyse the data. Geographic factors that increased the risk of seropositivity included higher rainfall North Coast location. Herd management factors that increased the risk of seropositivity included the use of Bos indicus genetics, cross-breeding and running several breeds in the one herd. Using fox control measures was found to be protective against infection with N. caninum. The risk of abortion was 12-fold greater in individual animals that were seropositive for N. caninum. Within a herd, the calving rate was 10.4% lower in herds with one or more N. caninum-positive animals (P = 0.03), but the difference in abortion rate was not significant between seropositive and seronegative herds (0.3% higher, P > 0.3). This study confirmed previous observations of increased risks for N. caninum seropositivity with being located in the coastal subtropics, some styles of herd management and canid exposure. In addition, it suggested that cross-breeding and proximity to an urban area may increase the risk, and that having pet dogs may reduce the risk of seropositivity. © 2017 State of New South Wales.

  15. Determining the Ratio of Animal Species in the Herd of Pre-Class Societies

    Directory of Open Access Journals (Sweden)

    Stegantsev Mark A.

    2013-09-01

    Full Text Available The article is devoted to the methodology of research of domestic animals herd composition in ancient societies, based on the materials of Late Bronze and Early Iron Age sites located in the Western part of forest-steppe and steppe of Western Siberia and Northern Kazakhstan. The theoretical portion of the article demonstrates that percentage composition of the ancient herd can be restored only by taking into account the early maturation of the domestic ungulates forming its component part. The values of their early maturation depend on the distribution of animals by age. The formulas, derived through herd models developed, make it possible to determine the required distribution, based on the number of animal units of different ages in osteological collections. They are not affected by the type of herd reproduction. The application of the derived formulas in order to determine the early maturation of large and small cattle, and horses in the settlements of certain cultures in forest, forest-steppe and steppe zones, has confirmed the adequacy of the model in explaining the archaeological data. It has also been shown that economic specialization of successive Late Bronze and Early Iron Age cultures in the region was determined mainly by the horse. The study of different methods of determining ancient herd composition has made it possible to come to the following conclusion. The method of transition from identifiable bones in the excavation to the number of animal units corresponding to them, and then, by determining early maturation of different species, to their ratio in the ancient herd, has an absolute priority as compared to the method of transition from the identifiable bones directly to herd composition.

  16. The Mexican American Heritage: With Writing Exercises.

    Science.gov (United States)

    Jimenez, Carlos M.

    Written by a Los Angeles history teacher frustrated by the lack of culturally relevant materials, this book covers some of the most interesting events in the history of Mexico and the heritage of Mexican Americans. Chapters are: (1) Indian Mexico (Teotihuacan, the Maya, the Toltecs, and the Aztecs); (2) La Conquista (Cortes and Moctezuma, conquest…

  17. Socioeconomic differences in obesity among Mexican adolescents

    Science.gov (United States)

    ULLMANN, S. HEIDI; BUTTENHEIM, ALISON M.; GOLDMAN, NOREEN; PEBLEY, ANNE R.; WONG, REBECA

    2012-01-01

    Objective We investigate socioeconomic disparities in adolescent obesity in Mexico. Three questions are addressed. First, what is the social patterning of obesity among Mexican adolescents? Second, what are the separate and joint associations of maternal and paternal education with adolescent obesity net of household wealth? Third, are there differences in socioeconomic status (SES) gradients among Mexican boys and girls, rural residents and non-rural residents? Methods Using data from the Mexican National Health Survey 2000 we examined the slope and direction of the association between SES and adolescent obesity. We also estimated models for sub-populations to examine differences in the social gradients in obesity by sex and non-rural residence. Results We find that household economic status (asset ownership and housing quality) is positively associated with adolescent obesity. High paternal education is related to lower obesity risk, whereas the association between maternal education and obesity is positive, but not always significant. Conclusion The household wealth components of SES appear to predispose Mexican adolescents to higher obesity risk. The effects of parental education are more complex. These findings have important policy implications in Mexico and the United States. PMID:20883181

  18. The Mexican American Heritage: With Writing Exercises.

    Science.gov (United States)

    Jimenez, Carlos M.

    Written by a Los Angeles history teacher frustrated by the lack of culturally relevant materials, this book covers some of the most interesting events in the history of Mexico and the heritage of Mexican Americans. Chapters are: (1) Indian Mexico (Teotihuacan, the Maya, the Toltecs, and the Aztecs); (2) La Conquista (Cortes and Moctezuma, conquest…

  19. Conflict Resolution between Mexican Origin Adolescent Siblings

    Science.gov (United States)

    Killoren, Sarah E.; Thayer, Shawna M.; Updegraff, Kimberly A.

    2008-01-01

    We investigated correlates of adolescents' sibling conflict resolution strategies in 246, two-parent Mexican origin families. Specifically, we examined links between siblings' conflict resolution strategies and sibling dyad characteristics, siblings' cultural orientations and values, and sibling relationship qualities. Data were gathered during…

  20. Psychology for the Mexican or the Masses?

    Science.gov (United States)

    Diaz-Guerrero, Rogelio

    1984-01-01

    Investigated the impact of traditional cultural beliefs, called historic-sociocultural premises (HSCPs), on peoples' interpersonal and emotional lives. Results indicated that people in Mexican societies hold similar sociocultural premises and that HSCPs are related to how people cope with stress, personality traits, and vocational choice. (LLL)

  1. Young Mexicans with a Spanish Heart

    Science.gov (United States)

    Meyerratken, Leila

    2005-01-01

    The author, a teacher at an Indiana middle school, describes how her Mexican ESL students took a stand and helped make a statement against racism. These students, who had a fascination with Asian culture, were indignant when they read an article about a street in Texas called "Jap Road." Adamant that the road name should be changed, the…

  2. Cultural Challenges Faced by Mexican Immigrant Students

    Science.gov (United States)

    Zugel, Kevin

    2012-01-01

    This purpose of this investigation is to explore the cultural challenges faced by Mexican immigrant students through the study of current literature. Four themes emerged as a result of the investigation: dominant pedagogy, educational skills, deficit model, and student identities. The themes are discussed and suggestions are made as to how these…

  3. Feminism and Mexican American Adolescent Women

    Science.gov (United States)

    Flores, Lisa Y.; Carrubba, Maria D.; Good, Glenn E.

    2006-01-01

    This study examined the psychometric properties of the Feminist Identity Development Scale (FIDS) and the Attitudes Toward Feminism and the Womens Movement Scale (FWM) with 389 Mexican American 11th-grade and 12th-grade women. Results indicated internal consistency coefficients of .61, .62, .76, and .77 for the FIDS Passive Acceptance, Revelation,…

  4. Mexican Americans: Sons of the Southwest.

    Science.gov (United States)

    Lamb, Ruth S.

    Concerned with the Mexican Americans, who constitute the largest ethnic group in the southwestern United States, this book traces the history of these people from the early explorations and colonizing efforts of the Spanish in North and South America during the 16th century to the present. Major divisions of this book are the Introduction,…

  5. Innovation strategies of Mexican pharmaceutical firms

    Directory of Open Access Journals (Sweden)

    José Luis Solleiro

    2010-01-01

    Full Text Available Mexican pharmaceutical market is the most important in Latin America and a significant number of global firms have different business activities in this country: production, licensing of patents, alliances with Mexican firms, distribution facilities or partnerships, etc. In terms of innovation, global pharmaceutical industry has passed through structural changes mainly of technological and institutional nature. These changes have been influential along the whole value chain and have triggered transformations in firm's organization, market structure and sector's investments. Mexico's industry, in spite of having a very attractive domestic market, has serious limitations for technology development. Very little resources are invested in R&D and lack of articulation between research labs and industry provoke that Mexico has only exceptional innovation achievements and a high technological dependence. At the same time, some Mexican companies have developed new strategies to be competitive in open markets and have shown that a combination of competitive intelligence, rapid adoption of technologies, collaboration with advanced firms and research institutes, permanent training and continuous improvement are key factors for success. This paper deals with the results of a piece of research aimed at developing a model for the effective transfer of technology for Mexican pharmaceutical firms, with a strong component of knowledge and skills to manage the flows of information, people and technologies among firms, research labs, universities and other health organizations.

  6. The Mexican-American and Dramatic Literature.

    Science.gov (United States)

    Serrano, Hector M.

    In the area of the arts, the Mexican American has discovered a rich cultural heritage which gives him a strong sense of pride and a deep feeling of satisfaction. A new interest in the literature of Mexico and the Southwestern states of Texas, Arizona, New Mexico, Colorado, and California has started the Chicano people reading classic and modern…

  7. Mexican-American: Movements and Leaders.

    Science.gov (United States)

    Larralde, Carlos

    Biographical studies of 20 influential Chicano leaders trace Mexican American history from 1848 to the present. The book is organized chronologically by four historical periods: (1) The Cortinista Movement, 1848-1876; (2) The Teresita Movement, 1888-1905; (3) The Magonista Movement, 1904-1919; and (4) The Chicano Activists, 1920 ;o the present.…

  8. Activity patterns of nesting Mexican Spotted Owls

    Science.gov (United States)

    David K. Delaney; Teryl G. Grubb; Paul Beier

    1999-01-01

    We collected 2,665 hr of behavioral information using video surveillance on 19 Mexican Spotted Owl (Strix occidentalis lucida) pairs between 25 April and 26 July 1996. Prey deliveries per day increased as the nesting season progressed, with an average of 2.68 prey deliveries during incubation, 4.10 items during brooding, and 4.51 items during the...

  9. Educating for Bilinguals in Mexican Transnational Communities.

    Science.gov (United States)

    Smith, Patrick H.; Martinez-Leon, Natalia

    2003-01-01

    Describes the educational situation facing "retornado" families and children, Mexican transnational immigrants moving between New York City and Puebla, Mexico. Examines factors underlying the current lack of first language and second language instruction for the Spanish-English bilinguals returning to live in Mexico. Offers suggestions…

  10. Civic Engagement Patterns of Undocumented Mexican Students

    Science.gov (United States)

    Perez, William; Espinoza, Roberta; Ramos, Karina; Coronado, Heidi; Cortes, Richard

    2010-01-01

    This study examined the civic engagement of undocumented Mexican students. Civic engagement was defined as providing a social service, activism, tutoring, and functionary work. Survey data results (n = 126) suggest that despite high feelings of rejection because of their undocumented status, part-time employment, and household responsibilities,…

  11. Treatment Acceptability among Mexican American Parents

    Science.gov (United States)

    Borrego, Joaquin, Jr.; Ibanez, Elizabeth S.; Spendlove, Stuart J.; Pemberton, Joy R.

    2007-01-01

    There is a void in the literature with regard to Hispanic parents' views about common interventions for children with behavior problems. The purpose of this study was to examine the treatment acceptability of child management techniques in a Mexican American sample. Parents' acculturation was also examined to determine if it would account for…

  12. Barreda, Vasconcelos, and Mexican Educational Reforms.

    Science.gov (United States)

    Skirius, John

    1983-01-01

    Reviews the contributions to Mexican education of Gabino Barredas' positivism between 1867-1898 and the contributions of Jose Vasconcelos during the 1920s. Discusses the secondary curriculum reforms of Barreda's era and the vocational education and the education for women and adults during the Vasconcelos era. (SB)

  13. Open Access to Mexican Academic Production

    Science.gov (United States)

    Adame, Silvia I.; Llorens, Luis

    2016-01-01

    This paper presents a description of the metadata harvester software development. This system provides access to reliable and quality educational resources, shared by Mexican Universities through their repositories, to anyone with Internet Access. We present the conceptual and contextual framework, followed by the technical basis, the results and…

  14. New offshore platform in the Mexican Gulf

    Energy Technology Data Exchange (ETDEWEB)

    Beisel, T.

    1982-04-01

    After a construction period of only 10 months, the second steel Offshore platform was recently completed in the Mexican Gulf. The pattern for this structure was the Cognac platform. The erection of the new platform, called the 'Cerveza' platform, is described in the article.

  15. Association between antibody status to bovine herpesvirus 1 and quality of milk in dairy herds in Poland.

    Science.gov (United States)

    Rola, J G; Larska, M; Grzeszuk, M; Rola, J

    2015-02-01

    Bovine herpesvirus 1 (BoHV1) is one of the most important pathogens of cattle; however, its effect on somatic cell count and milk components is not completely understood. The aim of the current study was to examine the effect of BoHV1 infection on quality of bovine bulk tank milk (BTM). A total of 1,790 individual blood samples collected at 28 dairy farms were used to determine the BoHV1 infection status of the herds with ELISA tests. The quality parameters of milk were evaluated by instrumental methods with BTM samples collected at monthly intervals from May 2011 to May 2012. The statistical analysis was performed to study the associations between BoHV1 herd status, quality of BTM, and herd-specific parameters. The risk factors influencing bulk milk somatic cell count (BMSCC) were estimated using the multivariable mixed-effects maximum likelihood regression model. The true prevalences of BoHV1 infection at the animal and herd levels were 49.3 and 64.6%, respectively. The average BMSCC differed significantly between the herds grouped accordingly to their BoHV1 infection status. Interestingly, the highest BMSCC was observed in the vaccinated herds (240.3×10(3) cells/mL). Additionally, the BoHV1 herd status had a significant effect on the fat content of BTM. The largest herds that were investigated had a BoHV1 seroprevalence over 30%. The herd status was considerably influenced by the numbers of cows in the herds. Besides, no significant differences in total bacterial count or protein content in milk from BoHV1-infected und uninfected herds were observed. An increase in BMSCC was observed during summer compared with the winter months regardless of the BoHV1 status of the herds. In the final multivariable regression model, the main risk factors associated with BMSCC were BoHV1 herd status, the percentage of BoHV1 infected animals in a herd, the number of cows in a herd, and the season. Our study suggests that BoHV1 infection may influence BMSCC levels, which are key

  16. The effect of alternative testing strategies and bio-exclusion practices on Johne's disease risk in test-negative herds.

    Science.gov (United States)

    More, S J; Sergeant, E S G; Strain, S; Cashman, W; Kenny, Kevin; Graham, D

    2013-03-01

    Herd classification is a key component of national Johne's disease (JD) control programs. Herds are categorized on the basis of test results, and separate sub-programs are followed for test-positive and test-negative herds. However, a test-negative herd result does not necessarily equate to JD freedom for reasons relating to disease pathogenesis and available diagnostic tests. Thus, in several countries, JD control programs define test-negative herds as having a "low risk" of infection below a specified prevalence. However, the approach is qualitative, and little quantitative work is available on herd-level estimates of probability of freedom in test-negative herds. This paper examines the effect over time of alternative testing strategies and bio-exclusion practices on JD risk in test-negative herds. A simulation model was developed in the programming language R. Key model inputs included sensitivity and specificity estimates for 3 individual animal diagnostic tests (serum ELISA, milk ELISA, and fecal culture), design prevalence, testing options, and testing costs. Key model outputs included the probability that infection will be detected if present at the design prevalence or greater (herd sensitivity; SeH), the probability that infection in the herd is either absent or at very low prevalence (i.e., less than the design prevalence; ProbF), the probability of an uninfected herd producing a false-positive result [P(False+)], and mean testing cost (HerdCost) for different testing strategies. The output ProbF can be updated periodically, incorporating data from additional herd testing and information on cattle purchases, and could form the basis for an output-based approach to herd classification. A high ProbF is very difficult to achieve, reflecting the low sensitivity of the evaluated tests. Moreover, ProbF is greatly affected by any risk of introduction of infection, decreasing in herds with poor bio-exclusion practices despite ongoing negative test results. The

  17. The new classification system for slaughter-pig herds in the Danish Salmonella surveillance-and-control program

    DEFF Research Database (Denmark)

    Alban, L.; Stege, Helle; Dahl, J.

    2002-01-01

    The Danish surveillance-and-control program for Salmonella in slaughter pigs was introduced in 1995. The key element of the program is a quick and correct identification of herds with high seroprevalence. After 5 years, the classification scheme was evaluated-and a revision was made. Data from two...... the Danish Salmonella Database including all herds in 2000. The classification scheme has been adjusted on the following points. (1) The sampling has been simplified into 60, 75, or 100 samples per herd per year depending on herd size. This means more-precise estimates for the seroprevalence among smaller...

  18. Epidemiological characteristics of bovine herpesvirus 1 infections determined by bulk milk testing of all Dutch dairy herds.

    Science.gov (United States)

    Van Wuijckhuise, L; Bosch, J; Franken, P; Frankena, K; Elbers, A R

    1998-02-21

    Samples of bulk milk were taken from all 33,636 Dutch dairy herds in November 1994 and tested for the presence of bovine herpesvirus 1 (BHV-1) antibodies with a gB-blocking ELISA. Sixteen per cent of the herds had a negative BHV-1 status in the bulk milk. Farms with only dairy cows were 1.9 times more likely to have a negative or weakly positive BHV-1 status than herds which also had beef/veal animals. Farms in areas containing less than one herd/km2 were 1.5 times more likely to have a negative or weakly positive BHV-1 status than herds in areas with more than three herds/km2. Differences in numbers of animals per unit area were not significantly associated with BHV-1 status. The probability of herds having a negative or weakly positive BHV-1 status decreased linearly with herd size by a factor of 1.2 per 10 animals. The purchase of stock was significantly associated with a negative or weakly positive BHV-1 status, but there was an interaction between farm type and purchase of stock. For farms with both dairy and beef/veal animals there was a weak association between the purchase of stock and BHV-1 status. For pure dairy herds the probability of having a negative or weakly positive BHV-1 status decreased linearly with the numbers of purchased stock by a factor of 1.3 per 10 animals purchased.

  19. Comparison between persisting anti-lipopolysaccharide antibodies and culture at postmortem in salmonella-infected cattle herds

    DEFF Research Database (Denmark)

    Hoorfar, Jeffrey; Wedderkopp, A.; Lind, P.

    1996-01-01

    Herds with recent clinical outbreaks of Salmonella dublin (7 herds) and S. typhimurium (4 herds) infections were followed serologically in O-antigen ELISAs over about one year, divided in four equal sampling phases. Animals found to be persistent high-reactors or seronegative at the end of the st...... in the S. dublin ELISA, alone. In conclusion, although serology based on the O-antigens appears to be useful to identify salmonella-infected herds, it seems to be insufficient for identification of persistently infected animals....

  20. Impact of vaccine herd-protection effects in cost-effectiveness analyses of childhood vaccinations. A quantitative comparative analysis

    Science.gov (United States)

    Maldonado, Yvonne; Ioannidis, John P. A.; Contopoulos-Ioannidis, Despina

    2017-01-01

    Background Inclusion of vaccine herd-protection effects in cost-effectiveness analyses (CEAs) can impact the CEAs-conclusions. However, empirical epidemiologic data on the size of herd-protection effects from original studies are limited. Methods We performed a quantitative comparative analysis of the impact of herd-protection effects in CEAs for four childhood vaccinations (pneumococcal, meningococcal, rotavirus and influenza). We considered CEAs reporting incremental-cost-effectiveness-ratios (ICERs) (per quality-adjusted-life-years [QALY] gained; per life-years [LY] gained or per disability-adjusted-life-years [DALY] avoided), both with and without herd protection, while keeping all other model parameters stable. We calculated the size of the ICER-differences without vs with-herd-protection and estimated how often inclusion of herd-protection led to crossing of the cost-effectiveness threshold (of an assumed societal-willingness-to-pay) of $50,000 for more-developed countries or X3GDP/capita (WHO-threshold) for less-developed countries. Results We identified 35 CEA studies (20 pneumococcal, 4 meningococcal, 8 rotavirus and 3 influenza vaccines) with 99 ICER-analyses (55 per-QALY, 27 per-LY and 17 per-DALY). The median ICER-absolute differences per QALY, LY and DALY (without minus with herd-protection) were $15,620 (IQR: $877 to $48,376); $54,871 (IQR: $787 to $115,026) and $49 (IQR: $15 to $1,636) respectively. When the target-vaccination strategy was not cost-saving without herd-protection, inclusion of herd-protection always resulted in more favorable results. In CEAs that had ICERs above the cost-effectiveness threshold without herd-protection, inclusion of herd-protection led to crossing of that threshold in 45% of the cases. This impacted only CEAs for more developed countries, as all but one CEAs for less developed countries had ICERs below the WHO-cost-effectiveness threshold even without herd-protection. In several analyses, recommendation for the

  1. Distant Neighbours: Different Visions about Mexican Archaeology

    Directory of Open Access Journals (Sweden)

    Luis Gómez Gastélum

    2014-05-01

    Full Text Available In 1972, Mexican archaeology experienced a major transformation due to the enactment of a Federal Law about archaeological, artistic, and historical monuments and zones, which changed the Mexican Government’s administration of Mexican archaeological heritage. In 1972, in West Mexico, an active group of archaeologists from the U.S.A. was working. They came from several universities and were also members of an academic association, the West Mexican Society for Advanced Study, that was based in Ajijic, Mexico, and comprised both U.S. and Mexican archaeologists. This group wrote to the government about their views of the new laws, and the government department concerned with their implementation, the Mexican National Institute of Anthropology and History (INAH – Instituto Nacional de Antropología e Historia, then responded with the Mexican Government’s official standpoint. In this paper, we analyze the positions of the West Mexican Society for Advanced Study, and INAH. We observe the sociopolitical and academic contexts from both U.S. and Mexican perspectives, and we offer explanations about their opposing views. We consider this episode to be a manifestation of the ideas circulating between U.S. and Mexican archaeologies.En 1972 la arqueología mexicana tuvo un cambio radical. En ese año fue promulgada la Ley Federal de Monumentos y Zonas Arqueológicos, Artísticos e Históricos. Esta ley cambió la manera en que el gobierno mexicano administraba el patrimonio arqueológico nacional. En dicho año, en el occidente de México, estuvo trabajando un grupo muy activo de arqueólogos estadounidenses, que si bien procedían de diversas universidades, también fueron miembros de una institución académica. La Sociedad de Estudios Avanzados del Occidente de México, con sede en Ajijic, México, reunió tanto a arquéologos estadounidenses como mexicanos. Los primeros escribieron un documento que contenía sus opiniones sobre la nueva ley y lo

  2. Racial Identity and Racial Treatment of Mexican Americans.

    Science.gov (United States)

    Ortiz, Vilma; Telles, Edward

    2012-04-01

    How racial barriers play in the experiences of Mexican Americans has been hotly debated. Some consider Mexican Americans similar to European Americans of a century ago that arrived in the United States with modest backgrounds but were eventually able to participate fully in society. In contrast, others argue that Mexican Americans have been racialized throughout U.S. history and this limits their participation in society. The evidence of persistent educational disadvantages across generations and frequent reports of discrimination and stereotyping support the racialization argument. In this paper, we explore the ways in which race plays a role in the lives of Mexican Americans by examining how education, racial characteristics, social interactions, relate to racial outcomes. We use the Mexican American Study Project, a unique data set based on a 1965 survey of Mexican Americans in Los Angeles and San Antonio combined with surveys of the same respondents and their adult children in 2000, thereby creating a longitudinal and intergenerational data set. First, we found that darker Mexican Americans, therefore appearing more stereotypically Mexican, report more experiences of discrimination. Second, darker men report much more discrimination than lighter men and than women overall. Third, more educated Mexican Americans experience more stereotyping and discrimination than their less-educated counterparts, which is partly due to their greater contact with Whites. Lastly, having greater contact with Whites leads to experiencing more stereotyping and discrimination. Our results are indicative of the ways in which Mexican Americans are racialized in the United States.

  3. Application of a Dot Blot Hybridization Platform to Assess Streptococcus uberis Population Structure in Dairy Herds

    Science.gov (United States)

    Albuquerque, Pedro; Ribeiro, Niza; Almeida, Alexandre; Panschin, Irena; Porfirio, Afonso; Vales, Marta; Diniz, Francisca; Madeira, Helena; Tavares, Fernando

    2017-01-01

    Streptococcus uberis is considered one of the most important pathogens associated with bovine mastitis. While traditionally acknowledged as an environmental pathogen, S. uberis has been shown to adopt a contagious epidemiological pattern in several dairy herds. Since different control strategies are employed depending on the mode of transmission, in-depth studies of S. uberis populations are essential to determine the best practices to control this pathogen. In this work, we optimized and validated a dot blot platform, combined with automatic image analysis, to rapidly assess the population structure of infective S. uberis, and evaluated its efficiency when compared to multilocus sequence analysis (MLSA) genotyping. Two dairy herds with prevalent S. uberis infections were followed in a 6 month period, in order to collect and characterize isolates from cows with persistent infections. These herds, located in Portugal (Barcelos and Maia regions), had similar management practices, with the herd from Barcelos being smaller and having a better milking parlor management, since infected cow segregation was immediate. A total of 54 S. uberis isolates were obtained from 24 different cows from the two herds. To overcome operator-dependent analysis of the dot blots and increase the technique's consistency and reliability, the hybridization signals were converted into probability values, with average probabilities higher than 0.5 being considered positive results. These data allowed to confirm the isolates' identity as S. uberis using taxa-specific markers and to determine the presence of virulence- and antibiotic resistance-related genes. In addition, MLSA allowed to disclose the most prevalent S. uberis clonal lineages in both herds. Seven different clusters were identified, with Barcelos showing a high clonal diversity and Maia a dominant lineage infecting most cows, suggesting distinct epidemiological patterns, with S. uberis displaying an environmental or contagious

  4. Effect of grazing on the cow welfare of dairy herds evaluated by a multidimensional welfare index.

    Science.gov (United States)

    Burow, E; Rousing, T; Thomsen, P T; Otten, N D; Sørensen, J T

    2013-05-01

    Structural development in the prime sector has led to increasing herd sizes and new barn systems, followed by less summer grazing for dairy cows in Denmark. Effects of grazing on single welfare measures in dairy cows - for example, the presence of integument alterations or mortality - have been studied under different conditions. However, the effect of grazing on welfare, conceptualised as the multidimensional physical and mental state of the animal, has not yet been studied in contemporary cubicle loose-housing systems. The aim of our study was to investigate, based on a Welfare Quality® inspired multidimensional dairy cow welfare assessment protocol, the within-herd effect of summer grazing compared with winter barn housing in Danish dairy herds with cubicle free-stall systems for the lactating cows. Our hypothesis was that cow welfare in dairy herds was better during summer grazing than during full-time winter housing. Furthermore, we expected improved welfare with an increase in daily summer grazing hours. In total, 41 herds have been visited once in the winter and once in the summer of 2010 to assess their welfare status with 17 different animal- and resource-based welfare measures. A panel of 20 experts on cattle welfare and husbandry evaluated the relative weight of the 17 welfare measures in a multidimensional assessment scheme. They estimated exact weights for a priori constituted severe compared with moderate scores of welfare impairment concerning each measure, as well as relevance of the measures in relation to each other. A welfare index (WI; possible range 0 to 5400) was calculated for each herd and season with a higher index indicating poorer welfare. The within-herd comparison of summer grazing v. winter housing considered all the 17 measures. The mean WI in summer was significantly lower (better) than in winter (mean 2926 v. 3330; paired t-test P = 0.0001) based on a better state of the integument, claw conformation and better access to water and

  5. Herd- and cow-level prevalence of digital dermatitis in the Netherlands and associated risk factors.

    Science.gov (United States)

    Holzhauer, M; Hardenberg, C; Bartels, C J M; Frankena, K

    2006-02-01

    The objective of this cross-sectional study was to reevaluate the prevalence of digital dermatitis (DD) and associated risk factors in The Netherlands. Between May 2002 and December 2003, information about the presence or absence of DD lesions and other claw disorders on the hind claws of dairy cows in The Netherlands was collected by 20 hoof trimmers during trimming of all dairy cows in 383 herds. A questionnaire was used to acquire information regarding management and housing. Additional information, such as parity, breed, and stage of lactation of the cows, was provided by the Dutch Herd Book Organization. Digital dermatitis was present in 21.2% (SE = 0.3) of the study population (n = 22,454 cows). The herd prevalence varied from 0% (9.1% of the herds) to 83.0%. Most common was herd prevalence between 5 and 10%. The Holstein-Friesian breed was at higher risk for DD [odds ratio (OR) = 1.7] than was the Meuse Rhine IJssel breed (dual purpose breed). The risk for DD decreased with increasing parity. Cows at the peak of their lactation (30 to 60 d in milk) and in the third parity had higher odds for DD in comparison with cows that were later than 60 DIM. The presence of other claw disorders, such as interdigital dermatitis/heel horn erosion (IDHE), interdigital hyperplasia (HYP), and interdigital phlegmon, appeared to be predisposing for DD. Based on estimation of the population-attributable fraction, it was concluded that if IDHE, HYP, and interdigital phlegmon were not present among the study population, respectively, 32.2, 9.0, and 1.1% of the DD cases could have been prevented. The risk for DD slightly decreased when cows affected by IDHE had access to pasture. Because of the interrelation between infectious claw disorders, an effective intervention strategy against DD should focus on an integrated approach to the control of all infectious claw diseases. Cows trimmed >12 mo before the study (during regular trimming of the entire herd) were at lower risk for DD

  6. Environmental contamination with Mycobacterium avium subsp. paratuberculosis in endemically infected dairy herds.

    Science.gov (United States)

    Smith, R L; Schukken, Y H; Pradhan, A K; Smith, J M; Whitlock, R H; Van Kessel, J S; Wolfgang, D R; Grohn, Y T

    2011-10-01

    Environmental contamination with Mycobacterium avium subsp. paratuberculosis (MAP) is thought to be one of the primary sources of infection for dairy cattle. The exact link between fecal shedding of MAP by individual cows and environmental contamination levels at the herd level was explored with a cross-sectional analysis of longitudinally collected samples on 3 dairy farms. Composite samples from multiple environmental sites in 3 commercial dairy herds in the Northeast US were cultured quarterly for MAP, providing 1131 samples (133 (11.8%) were culture-positive), and all adult animals in the herds were tested biannually by fecal culture (FC), for 6 years. Of the environmental sites sampled, manure storage areas and shared alleyways were most likely to be culture-positive. Environmental sample results were compared to FC results from either the concurrent or previous sampling date at both the herd and the pen level. At the herd level, a 1 log unit increase in average fecal shedding increased the odds of a positive non-pen environmental sample by a factor of 6 and increased the average amount of MAP in non-pen samples by 2.9 cfu/g. At the pen level, a 1 log unit increase in average fecal shedding in the pen increased the odds of a positive environment by a factor of 2.4 and the average amount of MAP was increased by 3.5 cfu/g. We were not able to model the relationship between non-pen environmental sample status and the distance between shedding animals and the sample's location, and neighboring pens did not significantly affect the results of the pen-level analysis. The amount of MAP in pen-level samples and the probability of a pen testing positive for MAP were both positively but non-significantly correlated with the number of animals in the pen shedding >30 cfu/g of MAP. At least 6 environmental samples met the criteria for the U.S. Voluntary Bovine Johne's Disease Control Program on 47 of the 72 sampling dates; of these, 19 of the 47 FC-positive sampling dates

  7. Spatiotemporal patterns, annual baseline and movement-related incidence of Streptococcus agalactiae infection in Danish dairy herds: 2000–2009

    DEFF Research Database (Denmark)

    Mweu, Marshal M.; Nielsen, Søren S.; Hisham Beshara Halasa, Tariq

    2014-01-01

    surveillance scheme as well as live cattle movements into dairy herds during the specified 10-year period. The results indicated that the predicted risk of a herd becoming infected with S. agalactiae varied spatiotemporally; the risk being more homogeneous and higher in the period after 2005. Additionally...... clustering of cases relative to the population of herds at risk nor spatial dependency between herds. Nevertheless, the results signal a need to beef up within-herd biosecurity in order to reduce the risk of new herd infections....

  8. What is herd immunity, and how does it relate to pediatric vaccination uptake? US parent perspectives.

    Science.gov (United States)

    Sobo, Elisa J

    2016-09-01

    In light of current concern over pediatric immunization rates, 53 US parents with at least one child kindergarten age or younger were surveyed and interviewed regarding vaccine decision making. Data were collected in 2014 in San Diego, California. Herd immunity was not a salient issue: only six (11.3%) referenced the term or concept spontaneously; others had to be prompted. Parents familiar with herd immunity (70%) variously saw it as not just unnecessary but unproven, illogical, unrealistic, and unreliable. For instance, parents questioned its attainability because many adults do not immunize themselves. Some understood the concept negatively, as an instance of "herd mentality." Further, having knowledge of herd immunity that public health experts would deem 'correct' did not lead to full vaccination. Implications of findings for understanding how the public makes use of scientific information, the potential role of public health messaging regarding altruism and 'free-riding,' and assumptions that vaccine-cautious parents would willfully take advantage of herd immunity are explored in relation to parent role expectations and American individualism.

  9. Herd immunity after vaccination: how to quantify it and how to use it to halt disease.

    Science.gov (United States)

    De Jong, M C; Bouma, A

    2001-03-21

    In comparison to unvaccinated individuals, vaccinated individuals have fewer clinical symptoms, reduced susceptibility and reduced infectivity. The first two effects of vaccination can mean that each vaccinated individual is protected against clinical symptoms. From experiments and field trials, the extent of individual protection can be determined by a statistical analysis of the resulting data. In addition, there is an effect of the vaccination on the populations in which one or more individuals are vaccinated. This effect on the population is due to the effects of vaccination on susceptibility and infectivity of the vaccinated individuals. The population effect is called herd immunity and is observed as a reduction in chance of becoming infected when being part of a population with some of the individuals vaccinated. Note that the protection by herd immunity applies to vaccinated individuals as well as to unvaccinated individuals. Thus, protection against disease can be achieved not only by vaccinating the individuals that have to be protected but also by vaccinating other individuals in the same population. Such an application of herd immunity is especially important in protecting farm animals. To plan and evaluate vaccination at the population level, the herd immunity needs to be quantified. It will be illustrated that it is possible, not only theoretically but also practically, to quantify herd immunity among farm animals with data from small-scale experiments as well as with data from field trials.

  10. Identifying risk factors associated with lameness in pasture-based dairy herds.

    Science.gov (United States)

    Ranjbar, S; Rabiee, A R; Gunn, A; House, J K

    2016-09-01

    Lameness is a significant welfare concern for dairy farmers and a major contributing economic loss to the dairy industry. Information is limited on environmental and managerial risk factors associated with lameness in Australian dairy herds. The objective of this study was to explore and quantify the environmental and management risk factors associated with lameness in pasture-based dairy herds. A cross-sectional study was conducted in 63 pasture-based dairy herds between 2011 and 2014, where all lactating cows were locomotion scored (scale 1-4) during a single visit. Environmental and management variables, such as length of main track and animal handling practices, were recorded during the visit. The prevalence of lameness was measured for each farm and associated risk factors were analyzed using a Generalized Linear Model, where farm was the unit of analysis. Estimated average prevalence of lameness was 18.9% (range 5 to 44.5%). The prevalence of lameness was associated with the amount of rainfall during the 30 d before the farm assessment, smoothness of concrete surface and available space per cow in the holding yard, and length of feed-pad available per cow. Inappropriate handling of cows on the track (e.g., causing sideways pushing among cows) was also a contributing risk factor to high prevalence of lameness in these dairy herds. The findings of this study suggest that by managing several environmental and farming practices, producers can reduce the prevalence of lameness, leading to improved productivity of their herds.

  11. Analytical study of index-coupled herd behavior in financial markets

    Science.gov (United States)

    Berman, Yonatan; Shapira, Yoash; Schwartz, Moshe

    2016-12-01

    Herd behavior in financial markets had been investigated extensively in the past few decades. Scholars have argued that the behavioral tendency of traders and investors to follow the market trend, notably reflected in indices both on short and long time scales, is substantially affecting the overall market behavior. Research has also been devoted to revealing these behaviors and characterizing the market herd behavior. In this paper we present a simple herd behavior model for the dynamics of financial variables by introducing a simple coupling mechanism of stock returns to the index return, deriving analytic expressions for statistical properties of the returns. We found that several important phenomena in the stock market, namely the correlations between stock market returns and the exponential decay of short-term autocorrelations, are derived from our model. These phenomena have been given various explanations and theories, with herd market behavior being one of the leading. We conclude that the coupling mechanism, which essentially encapsulates the herd behavior, indeed creates correlation and autocorrelation. We also show that this introduces a time scale to the system, which is the characteristic time lag between a change in the index and its effect on the return of a stock.

  12. Association between Dictyocaulus viviparus status and milk production parameters in Dutch dairy herds.

    Science.gov (United States)

    Dank, M; Holzhauer, M; Veldhuis, A; Frankena, K

    2015-11-01

    The objective of this study was to estimate the association between Dictyocaulus viviparus bulk tank milk (BTM) test results and milk production and milk composition parameters in adult Dutch dairy cattle herds. Bulk tank milk samples were collected in August and November 2013, and ELISA tests were performed. Two hundred BTM positive (BTM+) and 200 BTM negative (BTM-) herds were selected based on their BTM test result of November 2013, obtained from a list of farms that participated in the Dutch GD Animal Health voluntary monitoring program for controlling nematode infections. The relationship between D. viviparus BTM status and 3 production parameters (milk production, milk fat %, and milk protein %) in summer (June to August 2013) and autumn (September and October 2013) was investigated using generalized linear mixed models. Production data were available for 126 BTM- herds and 109 BTM+ herds. Results showed that a positive D. viviparus status was associated with decreased milk production (June: -1.01, July: -1.19, August: -1.68, September and October: -1.33kg/cow per d). Milk fat percentage was 0.14% and 0.08% lower during summer and autumn, respectively, in BTM+ herds. No significant association was demonstrated between a positive BTM test result and milk protein percentage. Because a strong correlation was present between the BTM status for D. viviparus and that for Ostertagia ostertagi, these losses cannot be attributed to one of the two parasites. However, it is clear that these parasite infections have a considerable effect on production.

  13. Determining the optimum replacement policy for Holstein dairy herds in Iran.

    Science.gov (United States)

    Kalantari, A S; Mehrabani-Yeganeh, H; Moradi, M; Sanders, A H; De Vries, A

    2010-05-01

    The objective of this study was to determine the optimum replacement policy for Holstein dairy herds in Iran using a dynamic programming model. Cows were described in terms of state variables that included milk production class, parity, pregnancy status, and month in milk with a 1-mo stage length. The objective function maximized the net present value of cows over a 15-yr planning horizon. Markov simulation was used to estimate expected herd dynamics under the optimal decision plan determined by dynamic programming. Stochastic elements included probabilities of pregnancy and abortion, production level, and involuntary culling. The optimum annual culling rate was estimated to be 31.4%, and cows had an expected herd life (time from first calving until culling) of 3.18 yr. High replacement cost and low carcass value resulted in only 2.87% voluntary culling (i.e., optimal model-based replacement). Assuming a heat detection rate of 0.4, cows averaged 2.8 services per lactation under the optimal policy. Sensitivity analyses were carried out to evaluate the effect of milk price, herd-average production, feed cost, heifer price, and carcass value on optimum replacement decisions. Herd-average production, replacement cost, and risk of involuntary culling were important factors affecting the optimal culling policy. Changes in the price of feed, calves, and milk and the probability of pregnancy had no considerable effect on the optimal policy considering the market situation in Iran during 2008.

  14. Interdigital dermatitis, heel horn erosion, and digital dermatitis in 14 Norwegian dairy herds

    DEFF Research Database (Denmark)

    Knappe-Poindecker, M.; Gilhuus, M.; Jensen, Tim Kåre

    2013-01-01

    wanted to compare diseased and healthy cows in all herds. The study included 14 dairy herds with a total of 633 cows. Eight herds had a history of ID and E, and 6 were control herds. All cows were scored for lameness, and infectious foot diseases on the hind feet were recorded after trimming. Swabs...... and biopsies were taken from the skin of 10 cows in each herd for bacterial analyses. In total, samples were taken from 34 cows with ID, 11 with E, 40 with both ID and E, and 8 with digital dermatitis (DD), and from 47 cows with healthy feet. Swabs were analyzed for identification and characterization of D...... with DD, and in 66.0% of cows with healthy feet. All serogroups of D. nodosus except F and M were detected, and all isolates were defined as benign by the gelatin gel test. Treponema spp. were detected in 50.0% of the cows with ID, in 9.1% with E, in 67.5% with ID and E, in all cows with DD, and in 6...

  15. The legal foundation of the production and use of herd-specific vaccines in Europe.

    Science.gov (United States)

    Attia, Y; Schmerold, I; Hönel, A

    2013-08-12

    In veterinary medicine, herd-specific vaccines are primarily used in farm animals if traditional vaccines are either unavailable or do not perform as expected. As autogenous products, these vaccines are exempt from Directive 2001/82/EC, and therefore the production and use of herd-specific vaccines are regulated differently in each member state of the European Union (EU). This study is an overview of the diverse legal statuses of herd-specific vaccines among European countries. The study was conducted by analyzing legal documents, tailored questionnaires answered by subject-related authorities from sixteen European countries, and related literature. These analyses revealed that tremendous heterogeneity exists with respect to the legal requirements for the production and use of herd-specific vaccines among the countries that were examined. In particular, certain countries have detailed and precise regulations for these vaccines, whereas the legislation regarding these vaccines is vague or even nonexistent in other nations. The implementation of standardized definitions, guidelines for vaccine use in the field, and regulations for vaccine production are essential prerequisites for achieving legal consistency across Europe. These measures would also help countries enact pertinent national legislation with less divergence regarding the production and use of herd-specific vaccines and ensure the existence of comparable safety and quality standards for these vaccines among European countries.

  16. Prevalence and risk factors associated with Chlamydophila abortus infection in dairy herds in Jordan.

    Science.gov (United States)

    Talafha, Abdelsalam Q; Ababneh, Mohammed M; Ababneh, Mustafa M; Al-Majali, Ahmad M

    2012-12-01

    A cross-sectional study was carried out to determine seroprevalence and to identify risk factors associated with Chlamydophila abortus infection in 62 nonvaccinated dairy herds (671 cows) in Jordan between January and June 2007. Information regarding herd management was recorded through a personal interview with farmers. Antibodies against C. abortus were detected using an ELISA test kit. Chi-square analysis and multivariable logistic regression model were used to identify risk factors associated with C. abortus seropositivity. The true prevalence of antibodies against C. abortus in individual cows and cattle herds were 19.9 % and 66.3 %, respectively. Univariable Chi-square analysis revealed three variables with P ≤ 0.25 that were further offered to multivariable logistic regression analysis. Small-sized herds were identified as a risk factor for seropositivity to C. abortus, while sweeping followed by water hosing and using disinfectants were identified as protective factors. Cows in the age groups of >8 and ≤ 10 years old and >2 and ≤ 6 years old had the highest and lowest significant seroprevalence to C. abortus, respectively. Results of this study indicated that C. abortus is highly prevalent in Jordan's dairy herds and Chlamydophila infection could be controlled by applying strict biosecurity measures in the dairy farms.

  17. Housing, Feeding and Management of Calves and Replacement Heifers in Swedish Dairy Herds

    Directory of Open Access Journals (Sweden)

    Liberg P

    2001-12-01

    Full Text Available A questionnaire was sent to 1500 randomly selected dairy herds in Sweden, asking for general information about the herds, including routines from birth to first calving and also routines at breeding, calving and during the grazing period. Fifty-eight percent of the questionnaires were returned. The preweaned calves were kept in individual calf pens in 68% and in group housing systems in 28% of the herds. Pens with slatted floors were the main housing system for replacement heifers from weaning to breeding, and tie stalls from breeding to first calving. Whole milk was used in 44% and milk replacements in 42% of the herds. The calves received, as a median, 2.5 litres of milk per meal and 2 meals per day. The median age at weaning was 8 weeks. Age was the single most common criteria used for deciding both weaning and breeding time. The median age when the heifers were first turned out to pasture was 6 months. Prophylactic anthelmintic treatment was used by 65% of the herds. The most common diet for replacement heifers before calving was a combination of grain, hay and silage.

  18. Trajectories of Mexican American and mainstream cultural values among Mexican American adolescents.

    Science.gov (United States)

    Knight, George P; Basilio, Camille D; Cham, Heining; Gonzales, Nancy A; Liu, Yu; Umaña-Taylor, Adriana J

    2014-12-01

    Mexican Americans are one of the largest and fastest growing ethnic groups in the United States, yet we have limited knowledge regarding changes (i.e., developmental trajectories) in cultural orientation based upon their exposure to the Mexican American and mainstream cultures. We examined the parallel trajectories of Mexican American and mainstream cultural values in a sample of 749 Mexican American adolescents (49 % female) across assessments during the fifth grade (approximately 11 years of age), the seventh grade (approximately 13 years of age) and the tenth grade (approximately 16 years of age). We expected that these values would change over this developmental period and this longitudinal approach is more appropriate than the often used median split classification to identify distinct types of acculturation. We found four distinct acculturation trajectory groups: two trajectory groups that were increasing slightly with age in the endorsement of mainstream cultural values, one of which was relatively stable in Mexican American cultural values while the other was declining in their endorsement of these values; and two trajectory groups that were declining substantially with age in their endorsement of mainstream cultural values, one of which was also declining in Mexican American cultural values and the other which was stable in these values. These four trajectory groups differed in expected ways on a number of theoretically related cultural variables, but were not highly consistent with the median split classifications. The findings highlight the need to utilize longitudinal data to examine the developmental changes of Mexican American individual's adaptation to the ethnic and mainstream culture in order to understand more fully the processes of acculturation and enculturation.

  19. Environmental and animal factors associated with gestation length in Holstein cows and heifers in two herds in the Czech Republic.

    Science.gov (United States)

    Tomasek, R; Rezac, P; Havlicek, Z

    2017-01-01

    The objective was to assess the effects of the month of conception, month of calving, sex of the calf, and twins on gestation length (GL) in Holstein cows and heifers in two dairy herds with different milk yields. The study was performed in northeast Czech Republic over a 6-year period on two commercial dairy herds with a mean annual milk production of 11,060 kg per cow in the higher milk-producing herd and 8854 kg per cow in the lower milk-producing herd. Gestation length in cows that conceived in different months of the year was longer in the higher milk-producing herd than that in the lower milk-producing herd throughout the year (P Gestation length in cows that conceived in different months of the year was longer than that in heifers through the whole year in both herds (P Gestation length in cows and heifers that conceived in the first months of the year was longer than in those that conceived in the last months of the year in both herds (P Gestation length in cows and heifers that calved in late fall and throughout winter was longer than in those that calved in spring and summer in both herds (P Gestation length in females carrying male calves was longer than in those carrying female calves (P Gestation length in cows (P < 0.0001) and heifers (P < 0.05) carrying singles was longer than in those carrying twins in both herds. In conclusion, results indicate that GL in Holstein cattle is associated with the month of conception, month of calving, herd, parity, sex of the calf, and twins.

  20. Risk factors for the introduction and within-herd transmission of Mycobacterium avium subspecies paratuberculosis (MAP infection on 59 Irish dairy herds

    Directory of Open Access Journals (Sweden)

    Cashman W

    2008-07-01

    Full Text Available Abstract Since 1994, Irish cattle have been exposed to greater risks of acquiring Mycobacterium avium subspecies paratuberculosis (MAP infection as a consequence of the importation of over 70,000 animals from continental Europe. In recent years, there has been an increase in the number of reported clinical cases of paratuberculosis in Ireland. This study examines the prevalence of factors that promote the introduction and within-herd transmission of Mycobacterium avium subspecies paratuberculosis (MAP on selected Irish dairy farms in the Cork region, and the association between these factors and the results of MAP screening tests on milk sock filter residue (MFR. A total of 59 dairy farms, selected using non-random methods but apparently free of endemic paratuberculosis, were enrolled into the study. A questionnaire was used to collect data about risk factors for MAP introduction and transmission. The MFR was assessed on six occasions over 24 months for the presence of MAP, using culture and immunomagnetic separation prior to polymerase chain reaction (IMS-PCR. Furthermore, blood samples from all entire male and female animals over one year of age in 20 herds were tested by ELISA. Eighteen (31% farms had operated as closed herds since 1994, 28 (47% had purchased from multiple sources and 14 (24% had either direct or indirect (progeny contact with imported animals. Milk and colostrum were mixed on 51% of farms, while 88% of farms fed pooled milk. Thirty (51% herds tested negative to MFR culture and IMS-PCR, 12 (20% were MFR culture positive, 26 (44% were IMS-PCR positive and seven (12% were both culture and IMS-PCR positive. The probability of a positive MFR culture was significantly associated with reduced attendance at calving, and with increased use of individual calf pens and increased (but not significantly if mulitiple suckling was practised. There was poor agreement between MFR culture and MFR IMS-PCR results, but moderate agreement

  1. Parasites of sheep herding dogs in central Germany.

    Science.gov (United States)

    Rehbein, Steffen; Kaulfuß, Karl-heinz; Visser, Martin; Sommer, Maria Franziska; Grimm, Felix; Silaghi, Cornelia

    2016-01-01

    This paper reports on endoparasite infections diagnosed in 2012 by standard coproscopical techniques and coproantigen Giardia ELISA in 165 dogs used for sheep herding in 36 farms in central Germany. The overall prevalence of dogs with evidence of endoparasite infections was 27.3% (95% CI 20.6-34.7). The most frequently identified faecal forms were those of ascarids (Toxocara, 6.7%; Toxascaris 3.6%), hookworms (5.5%) and taeniid cestodes (4.2%), followed by those of Trichuris whipworms (3.0%), Capillaria aerophila (1.8%), Angiostrongylus and Crenosoma lungworms (1.2% each) and Cystoisospora canis coccidians (0.6%). Molecular identification demonstrated the seven dogs shedding taeniid eggs positive for Taenia (T.) species tapeworms (five, T. hydatigena; one, T. ovis; one Taenia sp.). Screening of the faeces with the coproantigen ELISA revealed Giardia specific antigen in 5.5% of the samples. The majority of the dogs had evidence of single endoparasite infections (22.4%) while evidence for infection with two or three parasites concurrently was found in six (3.6%) and two (1.2%) of the dogs, respectively. Dogs ≤ 1 year (n = 19) were parasitized more frequently (p < 0.05) with overall gastrointestinal parasites (63.2% vs. 20.5%), ascarids (36.8% vs. 6.8%) and Giardia spp. (21.1% vs. 3.4%) than older dogs (n = 146). Dogs which had been wormed within six months of examination tested less frequently positive for gastrointestinal helminths compared to dogs not wormed (11.1% vs. 25.0%; p = 0.0567). In addition, ear swabs taken from 43 sheep dogs in 2012 were examined, and Otodectes cynotis mites were extracted from one dog. Identification of ectoparasites collected by full body search and combing from 113 sheep dogs in the years 2011 to 2013 revealed infestation of fleas and ticks (each up to five specimens per dog) on 13 and 108 dogs, respectively, with nine dogs carrying both fleas and ticks. Archaeopsylla erinacei, Ctenocephalides (C) canis, C. felis and Pulex irritans

  2. Annual incidence, prevalence and transmission characteristics of Streptococcus agalactiae in Danish dairy herds

    DEFF Research Database (Denmark)

    Mweu, Marshal M.; Nielsen, Søren S.; Hisham Beshara Halasa, Tariq;

    2012-01-01

    -level incidence rates and apparent prevalences of Streptococcus agalactiae (S. agalactiae) in the population of Danish dairy cattle herds over a 10-year period from 2000 to 2009 inclusive and (2) to estimate the herd-level entry and exit rates (demographic parameters), the transmission parameter, β, and recovery......Contagious mastitis pathogens continue to pose an economic threat to the dairy industry. An understanding of their frequency and transmission dynamics is central to evaluating the effectiveness of control programmes. The objectives of this study were twofold: (1) to estimate the annual herd...... rate for S. agalactiae infection. Data covering the specified period, on bacteriological culture of all bulk tank milk samples collected annually as part of the mandatory Danish S. agalactiae surveillance scheme, were extracted from the Danish Cattle Database and subsequently analysed...

  3. Control of bovine tuberculosis in a farmed red deer herd in England

    Science.gov (United States)

    Busch, F.; Bannerman, F.; Liggett, S.; Griffin, F.; Clarke, J.; Lyashchenko, K. P.; Rhodes, S.

    2017-01-01

    This report describes how Mycobacterium bovis infection was controlled and eventually eradicated in a farmed red deer herd in the north of England, following sustained tuberculin skin testing supplemented with serological (antibody) tests over a period of approximately two years. By taking advantage of the anamnestic antibody response produced by the skin test to detect skin test-negative, antibody-positive infected individuals, a total of 35 additional animals were identified, including 2 with gross visible lesions typical of bovine tuberculosis (BTB). Without detection and removal, these animals would have posed a continued risk of BTB persistence within the herd and potentially contributed to the spread of infection from deer into wildlife and surrounding cattle farms in an area of low BTB incidence. This case supports the use of ancillary diagnostic serological tests to speed up the resolution of incidents of BTB caused by M bovis in captive deer herds. PMID:28100768

  4. The challenge of detecting herds sub-clinically infected with Actinobacillus pleuropneumoniae.

    Science.gov (United States)

    Gottschalk, Marcelo

    2015-10-01

    The introduction into a naïve herd of animals sub-clinically infected with Actinobacillus pleuropneumoniae (App) is frequently the cause of clinical pleuropneumonia and the identification of such infected herds is a priority in the control of disease. Different serological tests for App have been developed and a number of these are routinely used. Some are species-specific whereas others identify more specifically the serotype/serogroup involved which requires updated information about important serotypes recovered from diseased pigs in a given area/country. Serotyping methods based on molecular techniques have been developed lately and are ready to be used by most diagnostic laboratories. When non-conclusive serological results are obtained, direct detection of App from tonsils is sometimes attempted. This review addresses different techniques and approaches used to monitor herds sub-clinically infected by this important pathogen. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Evaluation of Three Commercial Hoof-Care Products Used in Footbaths in Danish Dairy Herds

    DEFF Research Database (Denmark)

    Thomsen, Peter; Sørensen, Jan Tind; Ersbøll, Annette Kjær

    2008-01-01

    Digital dermatitis is a serious problem in dairy production in many countries. Footbaths have been used extensively for the prevention and cure of digital dermatitis. But there is a lack of scientific evidence regarding the effectiveness of hoof-care products used in footbaths. The objective...... was to evaluate 3 commercial hoof-care products in 12 Danish dairy herds (testing each product in 4 herds) using a controlled clinical trial. One-half of the herds were conventional and the other half was organically managed. The hoof-care products represented the 3 main groups of active compounds currently legal...... new infections). Percentage cured ranged from 13.6 to 100, and percentage new infections ranged from 0 to 35.5. For all hoof-care products, the difference between treatment and control sides was not statistically significant. Overall, there was no effect on percentage cured or percentage new...

  6. Meningococcal vaccines and herd immunity: lessons learned from serogroup C conjugate vaccination programs.

    Science.gov (United States)

    Trotter, Caroline L; Maiden, Martin C J

    2009-07-01

    Effective vaccines provide direct protection to immunized individuals, but may also provide benefits to unvaccinated individuals by reducing transmission and thereby lowering the risk of infection. Such herd immunity effects have been demonstrated following the introduction of meningococcal serogroup C conjugate (MCC) vaccines, with reductions in disease attack rates in unimmunized individuals and significantly lower serogroup C carriage attributable to the vaccine introduction. In the UK, targeting teenagers for immunization was crucial in maximizing indirect effects, as most meningococcal transmission occurs in this age group. Questions remain regarding the duration of herd protection and the most appropriate long-term immunization strategies. The magnitude of the herd effects following MCC vaccination was largely unanticipated, and has important consequences for the design and evaluation of new meningococcal vaccines.

  7. Mathematical Modeling of the Dynamics of Salmonella Cerro Infection in a US Dairy Herd

    Science.gov (United States)

    Chapagain, Prem; van Kessel, Jo Ann; Karns, Jeffrey; Wolfgang, David; Schukken, Ynte; Grohn, Yrjo

    2006-03-01

    Salmonellosis has been one of the major causes of human foodborne illness in the US. The high prevalence of infections makes transmission dynamics of Salmonella in a farm environment of interest both from animal and human health perspectives. Mathematical modeling approaches are increasingly being applied to understand the dynamics of various infectious diseases in dairy herds. Here, we describe the transmission dynamics of Salmonella infection in a dairy herd with a set of non-linear differential equations. Although the infection dynamics of different serotypes of Salmonella in cattle are likely to be different, we find that a relatively simple SIR-type model can describe the observed dynamics of the Salmonella enterica serotype Cerro infection in the herd.

  8. Modelling the economic impact of three lameness causing diseases using herd and cow level evidence

    DEFF Research Database (Denmark)

    Ettema, Jehan Frans; Østergaard, Søren; Kristensen, Anders Ringgaard

    2010-01-01

    profitability of such actions. An existing approach of modelling lameness as one health disorder in a dynamic, stochastic and mechanistic simulation model has been improved in two ways. First of all, three underlying diseases causing lameness were modelled: digital dermatitis, interdigital hyperplasia and claw......, marginal posterior probability distributions for disease prevalence in the specific herd are created in a Bayesian network. Random draws from these distributions are used by the simulation model to describe disease risk. Hereby field data on prevalence is used systematically and uncertainty around herd...... specific risk is represented. Besides the fact that estimated profitability of halving disease risk depended on the hyper-distributions used, the estimates differed for herds with different levels of diseases risk and reproductive efficiency....

  9. Factors Effecting of Milk Productions in Select Herds of Slovak Spotted Breed

    Directory of Open Access Journals (Sweden)

    Jozef Bujko

    2011-05-01

    Full Text Available The aim this work was analyse factors effecting on the milk production in select breeding herds of the Slovak spotted breed. Data were analysed using the Statistical Analysis System version 9.3.1 and linear model with fixed effects of herd-year-season of calving, genetic group, father, number of lactation and cod of milk production. Average of traits of milk production was 5266.4 kg of milk, 222.19 kg of fat, 177.79 kg of proteins and 251.37 kg of lactose. The linear model to represent coefficient determination R2 = 0.598099 for milk production with all fixed effects. The analysis by the effect was the highest effect of herd-years-season of calving (0.3724 than effect of father (0.3017. Correlation coefficients between milk, fat, protein, lactose in kgs (r=0.90826, r= 0.98260, r= 0.98830, were statistically high significant.

  10. Nitrate toxicosis in beef and dairy cattle herds due to contamination of drinking water and whey.

    Science.gov (United States)

    Yeruham, I; Shlosberg, A; Hanji, V; Bellaiche, M; Marcus, M; Liberboim, M

    1997-10-01

    Four cases of rarely reported nitrate toxicosis due to contamination of drinking water or whey were recorded in 2 beef and 2 dairy cattle herds. In the cases associated with water contamination, water containing ammonium nitrate as a fertilizer for irrigating orchards accidentally entered drinking water troughs for cattle through malfunctioning 1-way valves. The whey contamination in 1 instance was caused by transportation in containers which contained traces of concentrated ammonium nitrate; the 2nd case was induced by whey derived from the production of a specialty cheese produced by the incorporation of nitrate. Mortality occurred in 2 herds and abortions in the 2 other herds. Affected cows responded well to treatment, but some animals remained in a deteriorated physical condition for several months.

  11. Q fever outbreak in a goat herd--diagnostic investigations and measures for control.

    Science.gov (United States)

    Sting, Reinhard; Molz, Kerstin; Benesch, Christiane

    2013-01-01

    This is a case report about a Q fever infection of a goat herd with abortions and excretions of pathogens accompanied by human infection and disease. Following a diagnosis of Q fever in a goat herd, all animals were vaccinated with an inactivated phase 1 vaccine. The herd was kept isolated and animals were neither removed nor introduced so that monitoring of the course of the Q fever infection of the individual dam was possible. Over a period of two years following the diagnosis of a Q fever infection (abortion), diagnostic investigations on detection of Coxiella (C.) burnetii were performed using quantitative Real-Time PCR (qPCR) and for serological studies complement fixation test (CFT) and ELISA. Excretion of pathogens decreased from > 500 000 units per genital swab in the first year to control measures which were implemented after a round table meeting are illustrated and discussed.

  12. Sharks shape the geometry of a selfish seal herd: experimental evidence from seal decoys.

    Science.gov (United States)

    De Vos, Alta; O'Riain, M Justin

    2010-02-23

    Many animals respond to predation risk by forming groups. Evolutionary explanations for group formation in previously ungrouped, but loosely associated prey have typically evoked the selfish herd hypothesis. However, despite over 600 studies across a diverse array of taxa, the critical assumptions of this hypothesis have remained collectively untested, owing to several confounding problems in real predator-prey systems. To solve this, we manipulated the domains of danger of Cape fur seal (Arctocephalus pusillus pusillus) decoys to provide evidence that a selfish reduction in a seals' domain of danger results in a proportional reduction in its predation risk from ambush shark attacks. This behaviour confers a survival advantage to individual seals within a group and explains the evolution of selfish herds in a prey species. These findings empirically elevate Hamilton's selfish herd hypothesis to more than a 'theoretical curiosity'.

  13. Pleuritis in slaughter pigs: relations between lung lesions and bacteriology in 10 herds with high pleuritis.

    Science.gov (United States)

    Jirawattanapong, Pichai; Stockhofe-Zurwieden, Norbert; van Leengoed, Leo; Wisselink, Henk; Raymakers, Rudolf; Cruijsen, Toine; van der Peet-Schwering, Carola; Nielen, Mirjam; van Nes, Arie

    2010-02-01

    Pleuritis in slaughter pigs has increased in recent years in the Netherlands. The aim of the present study was to determine what respiratory pathogens were involved in pleuritis. In total, lungs of 968 slaughter pigs from 10 herds with high prevalence of pleuritis were morphologically examined for size, location, and type of lesions. Moreover, histology and bacteriology were performed. Examination of gross lung lesions showed 45% pleuritis, 14% pleuropneumonia and 38% catarrhal pneumonia. Peribronchiolar cuffing was found in 61 of 142 samples. Actinobacillus pleuropneumoniae was cultured from 22 lung samples from four herds. Pasteurella multocida was cultured from 55 lung samples in eight herds. No specific pattern with respect to the causal pathogens was found. In conclusion, no single infectious cause of pleuritis was found. A variety of infectious agents combined with environmental factors should be considered as a cause of pleuritis.

  14. Mexican ceratopsids: Considerations on their diversity and biogeography

    Science.gov (United States)

    Rivera-Sylva, Héctor E.; Frey, Eberhard; Stinnesbeck, Wolfgang; Guzmán-Gutiérrez, José Rubén; González-González, Arturo H.

    2017-04-01

    During the past decade, three taxa of ceratopsid ornithischians have been described from Mexico. Apparently, this group experienced a regional diversification in this area. To date Mexican Ceratopsia are represented by three species, one of which is a centrosaurine and two are chasmosaurines. Here we provide a critical review on Mexican ceratopsians and formally name a new centrosaurine ceratopsid species from the Campanian Aguja Formation as Yehuecauhceratops mudei. We also discuss possible causes for the rapid endemic diversification of Mexican ceratopsians.

  15. Genetic parameters and trends for production and reproduction traits of a Landrace herd in China

    Institute of Scientific and Technical Information of China (English)

    ZHANG Zhe; ZHANG Hao; PAN Rong-yang; WU Long; LI Ya-lan; CHEN Zan-mou; CAI Geng-yuan; LI Jia-qi; WU Zhen-fang

    2016-01-01

    The objectives of this study were to estimate the genetic parameters and the breeding progress in a Landrace herd in China, and to predict the potential beneifts by applying new breeding technology. Hereby, the performance records from a Land-race swine herd in China, composing over 33000 pigs born between 2001 and 2013, were colected on six economicaly important traits, i.e., average daily gain between 30–100 kg (ADG), adjusted backfat thickness at 100 kg (BF), adjusted days to 30 kg (D30), adjusted days to 100 kg (D100), number born alive (NBA), and total number born (TNB). The genetic parameters were estimated by restricted maximum likelihoodvia DMU, and realized genetic trends were analyzed. Based on the real population structure and genetic parameters obtained from this herd, the potential genetic trends by applying genomic selection (GS) were predictedvia a computer simulation study. Results showed that the heritability estimates in this Landrace herd were 0.55 (0.02), 0.42 (0.01), and 0.12 (0.01), for BF, D100, and TNB, respectively. Favorable genetic trends were obtained for D100, BF, and TNB due to direct selection, for ADG and NBA due to indirect selection. Long-term selection against D100 did not improve D30, though they are highly geneticaly correlated (0.64). Appling GS in such a swine herd, the genetic gain can be increased by 25%, or even larger for traits with low heritability or individuals without phenotypes before selection. It can be concluded that conventional breeding strategy was effective in the herd studied, while applying GS is promising and hence the road ahead in swine breeding.

  16. Factors associated with the occurrence of MRSA CC398 in herds of fattening pigs in Germany

    Directory of Open Access Journals (Sweden)

    Alt Katja

    2011-11-01

    Full Text Available Abstract Background The purpose of this study was to investigate the prevalence of MRSA in herds of fattening pigs in different regions of Germany, and to determine factors associated with the occurrence of this pathogen. For this purpose pooled dust samples were collected, and a questionnaire covered information regarding herd characteristics and management practices. Samples were pre-enriched in high-salt medium followed by selective enrichment containing cefoxitin/aztreonam, and culturing. Presumptive colonies were confirmed by multiplex-PCR targeting nuc-, mecA- and 16S rRNA-genes. Isolates were spa- and SCCmec-, and in selected cases, multilocus sequence-typed. Susceptibilities to 13 antimicrobials were determined by broth microdilution. Statistical analysis was carried out using backward stepwise logistic regression to calculate odds ratios with the MRSA test result as the outcome and herd characteristics as categorical covariates. Results Overall, 152 of 290 (52% fattening pig farms tested positive for MRSA. The prevalence in the east, north- and south-west of Germany ranged from 39 to 59%. t011 (66% and t034 (23% were the most commonly identified spa-types, and 85% of isolates carried SCCmec Type V. Identified spa-types were all associated with clonal complex CC398. Susceptibility testing revealed that all isolates were resistant to tetracycline. High resistance rates were also found for sulfamethoxazole/trimethoprim (40%, and quinupristin/dalfopristin (32%. In addition, 83% of strains displayed multidrug resistant (> 3 substance classes phenotypes. Logistic regression revealed herd size (large farms OR: 5.4; CI: 2.7-11.2; p Conclusions MRSA CC398 is widely distributed among herds of fattening pigs in Germany. Farm management plays a crucial role in the dissemination of MRSA with herd size, and production type representing potential major indicators.

  17. Assessing animal welfare in sow herds using data on meat inspection, medication and mortality.

    Science.gov (United States)

    Knage-Rasmussen, K M; Rousing, T; Sørensen, J T; Houe, H

    2015-03-01

    This paper aims to contribute to the development of a cost-effective alternative to expensive on-farm animal-based welfare assessment systems. The objective of the study was to design an animal welfare index based on central database information (DBWI), and to validate it against an animal welfare index based on-farm animal-based measurements (AWI). Data on 63 Danish sow herds with herd-sizes of 80 to 2500 sows and an average herd size of 501 were collected from three central databases containing: Meat inspection data collected at animal level in the abattoir, mortality data at herd level from the rendering plants of DAKA, and medicine records at both herd and animal group level (sow with piglets, weaners or finishers) from the central database Vetstat. Selected measurements taken from these central databases were used to construct the DBWI. The relative welfare impacts of both individual database measurements and the databases overall were assigned in consultation with a panel consisting of 12 experts. The experts were drawn from production advisory activities, animal science and in one case an animal welfare organization. The expert panel weighted each measurement on a scale from 1 (not-important) to 5 (very important). The experts also gave opinions on the relative weightings of measurements for each of the three databases by stating a relative weight of each database in the DBWI. On the basis of this, the aggregated DBWI was normalized. The aggregation of AWI was based on weighted summary of herd prevalence's of 20 clinical and behavioural measurements originating from a 1 day data collection. AWI did not show linear dependency of DBWI. This suggests that DBWI is not suited to replace an animal welfare index using on-farm animal-based measurements.

  18. Antimicrobial usage in 60 Swedish farrow-to-finish pig herds.

    Science.gov (United States)

    Sjölund, Marie; Backhans, Annette; Greko, Christina; Emanuelson, Ulf; Lindberg, Ann

    2015-10-01

    The aim of this study was to quantify antimicrobial consumption in Swedish farrow-to-finish pig herds. Sixty herds with 100 sows or more producing more than 500 fatteners per year participated in a study where data on antimicrobial consumption over a period of one year were collected. Data on antimicrobial use were collected by substance, administration route and per age category. Antimicrobial use was measured as defined daily doses and expressed as treatment incidence (TI) per 1000 pig-days at risk. The TIs for growing pigs varied between herds, from 1.6 to 116.0 with a median of 14.3. The highest TI was recorded for suckling piglets with a median of 54.7 (range; 1.6-367.9), while the median TIs for weaners, fatteners and adults were 6.2, 2.8 and 8.4, respectively (range; 0.0-260.5; 0.0-64.9; 0.0-45.0, respectively). The within herd TIs for the different age categories were not correlated. Individual treatment, mainly consisting of injectables, was the most common form of application except for weaners for which a majority (54.8%) of the treatments were group treatments. Benzylpenicillin was the most commonly applied substance except for weaners for which oral formulations of tylosin were most common. For fatteners, group treatments constituted 8.4% of the total TI. Group treatments with oral colistin were applied to suckling piglets in five herds. Group treatments were not applied to adult pigs. The TI for weaners was significantly lower for specific pathogen-free herds. The results show that the overall antimicrobial use in Swedish farrow-to-finish pig herds varied to a great extent, and the between-herd variation indicates that there is room for improvement of pig health. Targeting suckling piglets may be most beneficial, but further studies are required to identify specific focus areas which may reduce the need for antimicrobials in this particular age group. Copyright © 2015 Elsevier B.V. All rights reserved.

  19. Biosecurity level and health management practices in 60 Swedish farrow-to-finish herds.

    Science.gov (United States)

    Backhans, Annette; Sjölund, Marie; Lindberg, Ann; Emanuelson, Ulf

    2015-03-12

    Biosecurity measures are important tools to maintain animal health in pig herds. Within the MINAPIG project, whose overall aim is to evaluate strategies to raise pigs with less antimicrobial use, biosecurity was evaluated in medium to large farrow-to-finish pig herds in Sweden. In 60 farrow-to-finish herds with more than 100 sows, the biosecurity level was evaluated using a previously developed protocol (BioCheck). In a detailed questionnaire, internal and external biosecurity was scored in six subcategories each. An overall score for biosecurity was also provided. Information regarding production parameters as well as gender and educational level of personnel working with the pigs was also collected. Descriptive statistics were used to examine the recorded data. The median scores for external and internal biosecurity were 68 and 59, respectively, where 0 indicates total absence of biosecurity and 100 means maximal possible biosecurity. The subcategories for external and internal biosecurity that had the highest scores were "Purchase of animals" (external) and "Nursery unit"/"Fattening unit" (internal), while "Feed, water and equipment supplies" (external) and "Measures between compartments and equipment"/"Cleaning and disinfection" (internal) received the lowest scores. A female caretaker in the farrowing unit, a farmer with fewer years of experience and more educated personnel were positively associated with higher scores for some of the external and internal subcategories. In herds with <190 sows, fattening pigs were mixed between batches significantly more often than in larger herds. The herds in this study had a high level of external biosecurity, as well as good internal biosecurity. Strong biosecurity related to the purchase of animals, protocols for visitors, the use of all-in, all-out systems, and sanitary period between batches. Still, there is room for improvement in preventing both the introduction of disease to herds (external) and the spread of

  20. Seasoned Equity Offerings and"Herd Behavior"of Earnings Management

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    A model to explain the dynamic characters of earnings management was developed based on the interaction among several firms' disclosure policies. Under the condition of incomplete information, each firm's earnings management will be influenced by the earnings disclosure policies of other firms. It can lead to "herd behavior" of earnings management. This paper studies the relationship between earnings manipulation and rights issue policy based on the distribution of earnings after management. The results indicate that Chinese listed companies trend towards controlling ROE in the narrow ranges just above 6% and 10% .Therefore, "herd behavior" exists in the earnings management.