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Sample records for broiler breeder flock

  1. The prevalence of Campylobacter amongst a free-range broiler breeder flock was primarily affected by flock age.

    PubMed

    Colles, Frances M; McCarthy, Noel D; Layton, Ruth; Maiden, Martin C J

    2011-01-01

    Campylobacter successfully colonizes broiler chickens, but little is known about the longer term natural history of colonization, since most flocks are slaughtered at an immature age. In this study, the prevalence and genetic diversity of Campylobacter colonizing a single free-range broiler breeder flock was investigated over the course of a year. The age of the flock was the most important factor in determining both the prevalence and diversity of Campylobacter over time. There was no correlation with season, temperature, the amount of rain and sunshine, or the dynamics of colonization amongst geographically and temporally matched broiler flocks. The higher prevalence rates coincided with the age at which broiler chickens are typically slaughtered, but then in the absence of bio-security or other intervention methods, and despite changes in flock management, the prevalence fell to significantly lower levels for the remainder of the study. The genetic diversity of Campylobacter increased as the flock aged, implying that genotypes were accumulated within the flock and may persist for a long time. A better understanding of the ecology of Campylobacter within commercial chicken flocks will allow the design of more effective farm-based interventions.

  2. The long-term dynamics of Campylobacter colonizing a free-range broiler breeder flock: an observational study.

    PubMed

    Colles, Frances M; McCarthy, Noel D; Bliss, Carly M; Layton, Ruth; Maiden, Martin C J

    2015-04-01

    A free-range broiler breeder flock was studied in order to determine the natural patterns of Campylobacter colonization over a period of 63 weeks. Campylobacter sequence types (STs) were not mutually exclusive and on average colonized only 17.7% of the birds tested at any time. Campylobacter STs typically reached a peak in prevalence upon initial detection in the flock before tailing off, although the ST and antigenic flaA short variable region in combination were stable over a number of months. There was evidence that, with a couple of exceptions, the ecology of C. jejuni and C. coli differed, with the latter forming a more stable population. Despite being free range, no newly colonizing STs were detected over a 6-week period in autumn and a 10-week period in winter, towards the end of the study. There was limited evidence that those STs identified among broiler chicken flocks on the same farm site were likely to colonize the breeder flock earlier (R(2) 0.16, P 0.01). These results suggest that there is natural control of Campylobacter dynamics within a flock which could potentially be exploited in designing new intervention strategies, and that the two different species should perhaps be considered separately.

  3. Energy utilization and heat production of embryos from eggs originating from young and old broiler breeder flocks.

    PubMed

    Nangsuay, A; Meijerhof, R; Ruangpanit, Y; Kemp, B; van den Brand, H

    2013-02-01

    Two experiments were conducted to study the interaction between breeder age and egg size on the energy utilization (experiment 1) and heat production (experiment 2) of broiler embryos. In experiment 1, a total of 4,800 Ross-308 hatching eggs from 2 breeder ages (29 and 53 wk of age, or young and old) and, within each age, 2 egg sizes (57 to 61 g and 66 to 70 g, or small and large) were used. In experiment 2, a total of 240 Ross-308 hatching eggs from 2 breeder flocks at 29 (young) and 53 (old) wk of age, and which were selected from the same egg weight range (58 to 61 g), were tested in 2 replicate chambers. In experiment 1, it was shown that the amount of yolk relative to albumen was higher in the old flock eggs, and this effect was more pronounced in the large eggs. The old flock eggs, especially the larger egg size, contained more energy as a result of a greater yolk size. Energy utilization of the embryos was positively related to yolk size and the amount of energy transferred to yolk-free body (YFB) was largely determined by the available egg energy. The efficiency of converting egg energy into chick body energy (E(YFB)) was equal for both egg sizes and both breeder age groups. Chick YFB weight of young and old flock eggs was equal. However, dry YFB weight of chicks from old flock eggs was higher than in chicks from young flock eggs, which was associated with more protein and fat content and thus more energy accumulated into YFB. As a consequence, embryos derived from old flock eggs produced more heat from d 16 of incubation onward than those of the young flock eggs. In conclusion, the higher energy deposition into chick YFB of old flock eggs, leading to higher embryonic heat production, is the result of a higher amount of available energy in the egg and is not due to changes in E(YFB).

  4. Efficacy of Recombinant HVT-IBD Vaccines Administered to Broiler Chicks from a Single Breeder Flock at 30 and 60 Weeks of Age.

    PubMed

    Gelb, Jack; Jackwood, Daral J; Brannick, Erin M; Ladman, Brian S

    2016-09-01

    The efficacy of commercially available recombinant herpesvirus of turkeys-infectious bursal disease (rHVT-IBD) virus vaccines was studied in broiler chickens derived from an IBDV-vaccinated breeder flock at 30 wk of age (Trial 1) and 60 wk of age (Trial 2). In parallel, specific-pathogen-free (SPF) white leghorn chickens were used to evaluate vaccine efficacy to control for the effects of maternally derived antibodies (MDA) associated with the broiler chickens. Broilers and SPF leghorns were vaccinated subcutaneously in the neck at 1 day of age with Vaxxitek® HVT+IBD or Vectormune® HVT-IBD vaccines and were placed in isolators. On 10, 14, 18, 22, and 26 days postvaccination (DPV), vaccinated and nonvaccinated broilers and SPF leghorns were bled prior to challenge via the oral-nasal route with infectious bursal disease (IBD) reference strains ST-C, Delaware variant E (Del E), or contemporary field isolates DMV/5038/07 or FF6. Microscopic lesion assessment of the bursa was useful for assessing IBDV challenge in both rHVT-IBD-vaccinated broiler and SPF leghorn chickens. In general, rHVT-IBD vaccines induced greater protection as the time between vaccination and challenge increased. Based on incidence of microscopic lesions (IML) of bursa tissue, Vaxxitek HVT+IBD vaccination of SPF leghorns induced protection by 18 DPV and continued to protect 22 DPV and 26 DPV in Trials 1 and 2. Vectormune HVT-IBD vaccine induced protection of SPF leghorns by 18 or 22 DPV in Trial 1, depending upon the IBDV challenge strain. However, the onset of protection was delayed until 22 or 26 DPV in Trial 2. With either commercial vaccine, rHVT-IBD vaccination of broiler chickens was not as effective as was observed in SPF leghorns, based on IML of bursa tissue. However, Vaxxitek HVT+IBD vaccination protected broilers following challenge with ST-C in both Trial 1 (30-wk-old breeder progeny) and Trial 2 (60-wk-old breeder progeny). Partial protection against FF6 (Trial 1) and DMV/5038

  5. Impact of Skip-a-Day and Every-Day Feeding Programs on the Colonization of Salmonella Typhimurium in Broiler Breeder Pullets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Feed restriction during pullet rearing is required to maintain flock uniformity, limit body weight gain, and optimize broiler breeder reproductive fitness. The impact of restrictive feeding programs on Salmonella colonization after environmental challenge was investigated for broiler breeder pullet...

  6. Flies and Campylobacter Infection of Broiler Flocks

    PubMed Central

    Skovgård, Henrik; Bang, Dang Duong; Pedersen, Karl; Dybdahl, Jens; Jespersen, Jørgen B.; Madsen, Mogens

    2004-01-01

    A total of 8.2% of flies caught outside a broiler house in Denmark had the potential to transmit Campylobacter jejuni to chickens, and hundreds of flies per day passed through the ventilation system into the broiler house. Our study suggests that flies may be an important source of Campylobacter infection of broiler flocks in summer. PMID:15496257

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

    PubMed

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

    2012-12-01

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

  8. Impact of Feeding Systems and Vaccination Programs on Salmonella Enteritidis Colonization and Clearance of E. Coli In Broiler Broiler Breeders Pullets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Broiler breeder pullets from a single grandparent flock were in ovo-vaccinated with Marek's vaccines herpesvirus of turkey (HVT) + chicken herpesvirus (SB1) or a vector HVT + Infectious bursal disease (IBD) vaccine+SB1. The chicks were placed in an experimental broiler breeder facility at the Univer...

  9. Clearance of Escherichia coli After Intravenous Inoculation in Broiler Breeder Pullets Fed Skip a day, Every Day in the feeder and Every Day on the Litter

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The effect of feeding programs on the time of clearance of Escherichia coli in broiler breeder pullets was investigated. Broiler breeder pullets from a single grandparent flock were in ovo-vaccinated at 19 d of incubation with a vector HVT (vHVT) vector HVT + Infectious bursal disease (IBD) vaccine....

  10. Impact of Feeding Systems and Hatchery Vaccination Programs on Immune System Development, Salmonella Colonization, Clearance of E. Coli and Reproductive Traits In Broiler Breeder Pullets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Broiler breeder pullets from a single grandparent flock were vaccinated at 19 days of embryonation with Marek's vaccines HVT +SB1 or a Vector HVT + Infectious bursal disease (IBD) vaccine. The birds were placed in an experimental broiler breeder facility at the University of Georgia and fed ad libit...

  11. THE EFFECT OF EMBRYONIC AGE AND BREEDER FLOCK AGE ON THE GASTROINTESTINAL MICROBIOME OF DEVELOPING BROILER CHICKEN: POTENTIAL IMPLICATIONS FOR FOOD SAFETY

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Background: There are several food-safety issues related to broiler egg production, including the introduction/proliferation of zoonotic pathogens during embryonic gastrointestinal (GI) tract development. Little is known about the overall GI bacterial communities, how they change over time, or how ...

  12. Distribution and Genetic Profiles of Campylobacter in Commercial Broiler Production from Breeder to Slaughter in Thailand

    PubMed Central

    Prachantasena, Sakaoporn; Charununtakorn, Petcharatt; Muangnoicharoen, Suthida; Hankla, Luck; Techawal, Natthaporn; Chaveerach, Prapansak; Tuitemwong, Pravate; Chokesajjawatee, Nipa; Williams, Nicola; Humphrey, Tom; Luangtongkum, Taradon

    2016-01-01

    Poultry and poultry products are commonly considered as the major vehicle of Campylobacter infection in humans worldwide. To reduce the number of human cases, the epidemiology of Campylobacter in poultry must be better understood. Therefore, the objective of the present study was to determine the distribution and genetic relatedness of Campylobacter in the Thai chicken production industry. During June to October 2012, entire broiler production processes (i.e., breeder flock, hatchery, broiler farm and slaughterhouse) of five broiler production chains were investigated chronologically. Representative isolates of C. jejuni from each production stage were characterized by flaA SVR sequencing and multilocus sequence typing (MLST). Amongst 311 selected isolates, 29 flaA SVR alleles and 17 sequence types (STs) were identified. The common clonal complexes (CCs) found in this study were CC-45, CC-353, CC-354 and CC-574. C. jejuni isolated from breeders were distantly related to those isolated from broilers and chicken carcasses, while C. jejuni isolates from the slaughterhouse environment and meat products were similar to those isolated from broiler flocks. Genotypic identification of C. jejuni in slaughterhouses indicated that broilers were the main source of Campylobacter contamination of chicken meat during processing. To effectively reduce Campylobacter in poultry meat products, control and prevention strategies should be aimed at both farm and slaughterhouse levels. PMID:26886590

  13. Distribution and Genetic Profiles of Campylobacter in Commercial Broiler Production from Breeder to Slaughter in Thailand.

    PubMed

    Prachantasena, Sakaoporn; Charununtakorn, Petcharatt; Muangnoicharoen, Suthida; Hankla, Luck; Techawal, Natthaporn; Chaveerach, Prapansak; Tuitemwong, Pravate; Chokesajjawatee, Nipa; Williams, Nicola; Humphrey, Tom; Luangtongkum, Taradon

    2016-01-01

    Poultry and poultry products are commonly considered as the major vehicle of Campylobacter infection in humans worldwide. To reduce the number of human cases, the epidemiology of Campylobacter in poultry must be better understood. Therefore, the objective of the present study was to determine the distribution and genetic relatedness of Campylobacter in the Thai chicken production industry. During June to October 2012, entire broiler production processes (i.e., breeder flock, hatchery, broiler farm and slaughterhouse) of five broiler production chains were investigated chronologically. Representative isolates of C. jejuni from each production stage were characterized by flaA SVR sequencing and multilocus sequence typing (MLST). Amongst 311 selected isolates, 29 flaA SVR alleles and 17 sequence types (STs) were identified. The common clonal complexes (CCs) found in this study were CC-45, CC-353, CC-354 and CC-574. C. jejuni isolated from breeders were distantly related to those isolated from broilers and chicken carcasses, while C. jejuni isolates from the slaughterhouse environment and meat products were similar to those isolated from broiler flocks. Genotypic identification of C. jejuni in slaughterhouses indicated that broilers were the main source of Campylobacter contamination of chicken meat during processing. To effectively reduce Campylobacter in poultry meat products, control and prevention strategies should be aimed at both farm and slaughterhouse levels. PMID:26886590

  14. An examination of the role of feeding regimens in regulating metabolism during the broiler breeder grower period 2. Plasma hormones and metabolites

    Technology Transfer Automated Retrieval System (TEKTRAN)

    A trial was conducted to determine the effects of different feeding regimens on plasma hormone and metabolite levels in 16 week old broiler breeder pullets. A flock of 350 Cobb 500 breeder pullets was divided in two at 4 weeks of age and fed either everyday (ED) or skip-a-day (SKIP) from 4 to 16 wee...

  15. Serological Incidence of Avian Reovirus Infection in Broiler-breeders and Progeny in Nova Scotia

    PubMed Central

    Ide, P. R.; Dewitt, W.

    1979-01-01

    The plaque neutralization test and the agar gel precipitation test were used to detect neutralizing and precipitating antibody to avian reovirus strain WVU2937 in sera from 14 commercial broiler breeder flocks and eight progeny flocks. Ten breeder flocks (71%) possessed positive agar gel precipitation reactors (598 sera tested) and 12 (86%) possessed plaque neutralization reactors (114 serum pools tested). All broiler flocks possessed agar gel precipitation reactors, but these were not examined for neutralizing antibody. As no avian reovirus vaccine had been used in Canada prior to this survey these reactions were presumably due to natural infection. Clinical evidence suggested that such infection was asymptomatic in most cases. The development and persistence of antibody to reovirus strain WVU2937 was followed in chicks exposed to the virus by oral inoculation or by contact. Neutralizing antibody was demonstrated in all birds by postinoculation day 17 and this persisted for at least six months. Precipitating antibody was also demonstrated in most chicks by postinoculation day 17, but by six months only 12% of the chicks were still agar gel precipitation positive. PMID:231481

  16. Illuminance and egg production in broiler breeders.

    PubMed

    Lewis, P D; Danisman, R; Gous, R M

    2009-03-01

    1. Ross broiler breeders were reared at a nominal illuminance of 15, 20 or 45 lux and transferred to a nominal illuminance of 25, 55 or 70 lux at 20 weeks. 2. There were no significant interactions between the response to illuminance during rearing and in lay. This means that it matters not whether illuminance is increased, decreased or held constant on transfer to the laying house, provided it equals or exceeds the biological optimum for satisfactory egg production. 3. Whilst there were no significant effects of illuminance in either the rearing period or laying periods on egg numbers, peak rate of lay, terminal rate of lay, egg mass output or liveability, meta-analyses of these and other data indicated biological optima of 15 lux during rearing and 7 lux in the laying period. Birds reared at 45 lux had a lower mean egg weight (and earlier sexual maturity) than birds reared at 15 lux, and hens illuminated at 25 lux in the laying period laid more eggs on the floor than at either 55 or 70 lux. 4. Typical primary breeder recommendations of 10-20 lux during rearing and 30-60 lux in lay are appropriate for floor-housed birds; however, an illuminance of 7 lux could be used for caged birds, subject to welfare-code compliance.

  17. Salmonella in broiler flocks in the republic of Ireland.

    PubMed

    Gutierrez, Montserrat; Fanning, June; Murphy, Anne; Murray, Gerardine; Griffin, Margaret; Flack, Alma; Leonard, Nola; Egan, John

    2009-01-01

    In order to obtain an estimation of the prevalence of Salmonella spp. in flocks of broilers in the Republic of Ireland, a study was conducted in 2006 in a total of 362 broiler flocks associated with four integrated companies. Salmonella spp. was isolated from 27.3% of flocks, and eight Salmonella serovars were identified, none of which were Salmonella Enteritidis or Salmonella Typhimurium. The most prevalent serovar was Salmonella Mbandaka, followed by Salmonella Kentucky, which respectively accounted for 61.6% and 27.0% of positive samples. Notable differences were observed among the flocks associated with different integrated companies, both in the Salmonella spp. prevalence and in the serovar distribution. Results from routine official Salmonella testing in broiler production in 2006 showed similar serovar distribution within each integrated company from the associated hatchery and factory samples. In our study, differences in the prevalence of Salmonella at farm level did not correlate with differences in the percentages of positive chicken carcasses officially tested, which were low, for all the four companies investigated. Given the high prevalence of Salmonella Mbandaka, all human isolates obtained in the Republic of Ireland from 2003 to 2006 were compared to a subset of poultry isolates by pulsed-field gel electrophoresis, but an epidemiological link between the animal and the human strains could not be established. Finally the antimicrobial resistance analysis indicated a low proportion of resistant strains among the broiler flock isolates. PMID:19061369

  18. Photoperiod and oviposition time in broiler breeders.

    PubMed

    Lewis, P D; Backhouse, D; Gous, R M

    2004-08-01

    1. Oviposition times were recorded for broiler breeder hens under 8-, 10-, 11-, 12-, 13-, 14- and 16-h photoperiods. 2. Mean oviposition time (MOT) was delayed relative to dawn by approximately 0.5 h for each 1-h increase in photoperiod up to 14 h, but was similar for 14- and 16-h photoperiods. However, the 0.5 h/h regression for the time when half the eggs were laid continued through to 16 h. 3. The rate of change in MOT for each 1-h increase in < or = 14-h photoperiod was similar to that reported for early and modern egg-type hybrids, but, compared with modern genotypes, time of lay itself was 1 h later than white-egg and 2.5 h later than brown-egg hybrids. 4. At photoperiods < or = 12.25 h, the number of eggs laid before dawn increased by 4-5% for each 1-h reduction in daylength.

  19. Application OF LIBS To Estimate The Age Of Broiler Breeders

    NASA Astrophysics Data System (ADS)

    Salam, Z. Abdel; Harith, M. A.

    2011-09-01

    Laser Induced Breakdown Spectroscopy (LIBS) is a well-known spectrochemical elemental analysis technique. In our investigations of the LIBS spectra it has been found that there is a remarkable correlation between the ionic to atomic spectral lines emission ratio and the surface hardness of eggshell for two Different Broiler Breeder at different age. The proposed technique has been applied successfully in poultry science to estimate the age of broiler breeders by measuring the surface hardness of their eggshell. The experiments have been performed on two different strains, Arbor Acres plus (AAP) and Hubard Classic (HC), and the results were satisfactory.

  20. Occurrence and characterization of rotavirus A in broilers, layers, and broiler breeders from Brazilian poultry farms.

    PubMed

    Beserra, L A R; Barbosa, B R P; Bernardes, N T C G; Brandão, P E; Gregori, F

    2014-03-01

    Rotaviruses are a major cause of diarrhea in humans and animals, including several mammalian and avian species. Using different PCR protocols, we report the occurrence of rotavirus A in 21 (53.84%; 21/39) from 39 fecal pool samples of broilers, layers, and broiler breeders from Brazilian avian farms. We typed the G5, G8, G11, G19, and P[31] genotypes. PMID:24758129

  1. Constant photoperiods and sexual maturity in broiler breeder pullets.

    PubMed

    Lewis, P D; Backhouse, D; Gous, R M

    2004-08-01

    1. Broiler breeder pullets were maintained on 10-, 11-, 12-, 13-, 14- or 16-h photoperiods to determine the effect of constant photoperiods on sexual development in broiler breeders. The birds were fed to achieve a 2100 g body weight at approximately 17 or 20 weeks to see if the photosexual response was modified by rate of growth. 2. In both body weight groups, pullets maintained on 10h were the first to reach sexual maturity (50 eggs/100 bird-d), and these and the 11-h pullets matured significantly earlier than any of the other photoperiod groups. Pullets maintained on 13 or 14 h matured latest, at about 3 weeks after the 10-h pullets, though both were only marginally later than the 12- or 16-h birds. These differences in maturation probably reflect the different rates at which photorefractoriness is dissipated in broiler breeders reared on photoperiods that vary in their degree of stimulatory competence. 3. There were no significant interactions among the photoperiods and the ages at 2100 g; faster-growing birds consistently matured about 10 d earlier than conventionally grown pullets.

  2. Effects of preincubation heating of broiler hatching eggs during storage, flock age, and length of storage period on hatchability.

    PubMed

    Gucbilmez, M; Ozlü, S; Shiranjang, R; Elibol, O; Brake, J

    2013-12-01

    The effects of heating of eggs during storage, broiler breeder age, and length of egg storage on hatchability of fertile eggs were examined in this study. Eggs were collected from Ross 344 male × Ross 308 broiler breeders on paper flats, held overnight (1 d) at 18°C and 75% RH, and then transferred to plastic trays. In experiment 1, eggs were obtained at 28, 38, and 53 wk of flock age. During a further 10 d of storage, eggs either remained in the storage room (control) or were subjected to a heat treatment regimen of 26°C for 2 h, 37.8°C for 3 h, and 26°C for 2 h in a setter at d 5 of storage. In experiment 2, eggs from a flock at 28 wk of age were heated for 1 d of a 6-d storage period. Eggs from a 29-wk-old flock were either heated at d 1 or 5 of an 11-d storage period in experiment 3. In experiment 4, 27-wk-old flock eggs were heated twice at d 1 and 5 of an 11-d storage period. Control eggs stored for 6 or 11 d were coincubated as appropriate in each experiment. Heating eggs at d 5 of an 11-d storage period increased hatchability in experiment 1. Although no benefit of heating 28-wk-old flock eggs during 6 d of storage in experiment 2 was observed, heating eggs from a 29-wk-old flock at d 1 or 5 of an 11-d storage period increased hatchability in experiment 3. Further, heating eggs from a 27-wk-old flock twice during 11 d of storage increased hatchability in experiment 4. These effects were probably due to the fact that eggs from younger flocks had been reported to have many embryos at a stage of development where the hypoblast had not yet fully developed (less than EG-K12 to EG-K13), such that heating during extended storage advanced these embryos to a more resistant stage.

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

    PubMed

    Sommer, H M; Heuer, O E; Sørensen, A I V; Madsen, M

    2013-08-01

    For more than a decade human campylobacteriosis has been the leading zoonosis in many developed countries. Consumption of poultry or poultry products has been identified as the primary source of infection in humans. This study was conducted to identify risk factors for the occurrence of Campylobacter in Danish broiler flocks. The study was based on a large data set consisting of Campylobacter positive status for nearly 6000 broiler flocks and 43 explanatory variables. Data were obtained from the Danish Campylobacter surveillance programme in poultry and from the responses to a standardized questionnaire answered via interviews with broiler farm owners. Two hundred and forty broiler farms, comprising 539 broiler houses, were included in the study and their Campylobacter status was followed over a 2-year period (1999-2000). The large number of observations made it possible to carry out a multivariate analysis including all 43 variables. A multivariate analysis was conducted using a generalized linear model, and the correlations between the houses from the same farms were accounted for by adding a variance structure to the model. The procedures for analyses included backward elimination, forward selection and expanding of the number of observations used in the variance analysis along with the reduction of the number of parameters in the model. The unit of analysis was 'broiler house', meaning that all results from a broiler house were aggregated into one prevalence figure (number of positive flocks/total number of flocks delivered over the 2-year period). The following factors were found to be significantly associated with the occurrence of Campylobacter in the broiler flocks: old broiler houses, late introduction of whole wheat in the feed, relatively high broiler age at slaughter, improper rodent control, large number of chimneys on the broiler house, farm located in an area with a high density of cattle farms, having more than one broiler house on the farm, and

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

    PubMed

    Sommer, H M; Heuer, O E; Sørensen, A I V; Madsen, M

    2013-08-01

    For more than a decade human campylobacteriosis has been the leading zoonosis in many developed countries. Consumption of poultry or poultry products has been identified as the primary source of infection in humans. This study was conducted to identify risk factors for the occurrence of Campylobacter in Danish broiler flocks. The study was based on a large data set consisting of Campylobacter positive status for nearly 6000 broiler flocks and 43 explanatory variables. Data were obtained from the Danish Campylobacter surveillance programme in poultry and from the responses to a standardized questionnaire answered via interviews with broiler farm owners. Two hundred and forty broiler farms, comprising 539 broiler houses, were included in the study and their Campylobacter status was followed over a 2-year period (1999-2000). The large number of observations made it possible to carry out a multivariate analysis including all 43 variables. A multivariate analysis was conducted using a generalized linear model, and the correlations between the houses from the same farms were accounted for by adding a variance structure to the model. The procedures for analyses included backward elimination, forward selection and expanding of the number of observations used in the variance analysis along with the reduction of the number of parameters in the model. The unit of analysis was 'broiler house', meaning that all results from a broiler house were aggregated into one prevalence figure (number of positive flocks/total number of flocks delivered over the 2-year period). The following factors were found to be significantly associated with the occurrence of Campylobacter in the broiler flocks: old broiler houses, late introduction of whole wheat in the feed, relatively high broiler age at slaughter, improper rodent control, large number of chimneys on the broiler house, farm located in an area with a high density of cattle farms, having more than one broiler house on the farm, and

  5. Diseases diagnosed in broiler chicken flocks in Victoria, Australia, 1977 to 1984.

    PubMed

    Reece, R L; Beddome, V D; Barr, D A

    1985-03-23

    During the period July 1977 to June 1984, specimens from 1402 broiler chicken flocks were submitted to the Veterinary Research Institute, Victoria, Australia for investigation of morbidity, mortality and, or, poor performance. A total of 19,450 post mortem examinations, as well as numerous ancillary tests, were performed. The findings on these flocks are presented and the consequences of some particular diseases noted.

  6. Associations between vaccinations against protozoal and viral infections and Salmonella in broiler flocks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Reducing the burden of Salmonella in broiler flocks presents a challenge for public health and for sustainability of the industry. A number of other infections are simultaneously controlled in grow-out broilers world-wide by vaccination. The purpose of this exploratory analysis was to test, in a f...

  7. Campylobacter detection in broiler ceca at processing - a three year 211 flock survey

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Campylobacter is associated with live broilers and chicken meat products. There is some discussion in the literature about the possibility that Campylobacter prevalence in broilers could be affected by season or weather conditions. The objective of this study was to measure the flock prevalence of...

  8. Dynamics of populations of Campylobacter jejuni in two grandparent broiler breeder farms: persistent vs. transient strains.

    PubMed

    Perez-Boto, D; Garcia-Peña, F J; Abad-Moreno, J C; Echeita, M A

    2012-09-14

    The objectives of the study were to characterize and investigate the populations of Campylobacter jejuni in two grandparent broiler breeder farms over four years. Caecal as well as farm environmental samples were obtained. Campylobacter isolates were characterized by macrorestriction profile (SmaI and KpnI-PFGE) and PCR-RFLP of the flaA gene. Susceptibility tests against seven antimicrobials were also performed. Birds were negative for Campylobacter spp. when they came to these two production farms (20 weeks), and most of the flocks remained uncolonized until they were 23 weeks old. Eighteen genotypes were characterized, with one of them (genotype 2) appearing and persisting over the study period in the two farms. In general, the strains exhibited high genetic stability, and most of them could be seen as transient in the farms, being substituted by other strains when their flock was substituted. Only one environmental sampling was positive for C. jejuni. Two different genotypes were characterized; one of them was isolated from the birds of that farm two years before. The susceptibility data point to the idea of an environmental source or reservoir of this genotype. Regarding the susceptibility of the populations, as other studies have shown, quinolone resistance (alone or combined with other resistances) was the most frequent: 68.5%. Quinolone- and multidrug-resistant strains are a matter of concern in public health. In conclusion, this survey shows the complexity of the study of the colonization of farms by C. jejuni.

  9. Clinical outbreak of Bordetella avium infection in two turkey breeder flocks.

    PubMed

    Kelly, B J; Ghazikhanian, G Y; Mayeda, B

    1986-01-01

    An acute upper respiratory disease was observed in two broad-breasted white (BBW) turkey primary breeder flocks. Associated clinical signs included sneezing, depression, and a deep dry cough originating from large conducting airways. Morbidity reached approximately 15-20% of the hens in an affected house. None of the turkeys died, and total feed consumption was not affected. A minimal effect upon egg production was noticed. Sera from an acutely affected flock exhibited a marked rise in titer to Bordetella avium compared with preinfection sera samples. In Case 1, B. avium was isolated in pure culture from affected birds. In Case 2, B. avium was diagnosed by serological results and clinical signs; bacteriological examination was not attempted. The findings presented here are consistent with an acute clinical outbreak of B. avium-induced turkey rhinotracheitis (turkey coryza) in BBW turkey breeder hens. PMID:3729868

  10. Clinical outbreak of Bordetella avium infection in two turkey breeder flocks.

    PubMed

    Kelly, B J; Ghazikhanian, G Y; Mayeda, B

    1986-01-01

    An acute upper respiratory disease was observed in two broad-breasted white (BBW) turkey primary breeder flocks. Associated clinical signs included sneezing, depression, and a deep dry cough originating from large conducting airways. Morbidity reached approximately 15-20% of the hens in an affected house. None of the turkeys died, and total feed consumption was not affected. A minimal effect upon egg production was noticed. Sera from an acutely affected flock exhibited a marked rise in titer to Bordetella avium compared with preinfection sera samples. In Case 1, B. avium was isolated in pure culture from affected birds. In Case 2, B. avium was diagnosed by serological results and clinical signs; bacteriological examination was not attempted. The findings presented here are consistent with an acute clinical outbreak of B. avium-induced turkey rhinotracheitis (turkey coryza) in BBW turkey breeder hens.

  11. Constant photoperiods and eggshell quality in broiler breeder pullets.

    PubMed

    Backhouse, D; Lewis, P D; Gous, R M

    2005-04-01

    Broiler breeder pullets were exposed to constant 10-, 11-, 12-, 13-, 14- or 16-h photoperiods from 3 d of age. Egg weight, eggshell weight and shell thickness index were determined at 52 weeks of age. Egg weight increased by 0.31 g, shell weight decreased by 30 mg and shell thickness index decreased by 0.57 mg/cm2 for each one-hour increase in photoperiod. Whilst the changes in egg weight and eggshell thickness index might be overstated because eggs were collected at the same chronological time, the effect of time of egg-laying within the day was minimal in comparison, and did not negate the conclusion that egg weight increases, and shell weight and thickness index decrease with lengthening photoperiods. The effect of photoperiod on eggshell quality was not due to differences in the rate of lay between treatments. Shell weight was unaffected by time of lay.

  12. The broiler breeder paradox: ethical, genetic and physiological perspectives, and suggestions for solutions.

    PubMed

    Decuypere, E; Bruggeman, V; Everaert, N; Li, Yue; Boonen, R; De Tavernier, J; Janssens, S; Buys, N

    2010-10-01

    1. Due to intensive selection, broiler chickens became the most efficient meat-producing animals because of their fast growth, supported by a virtually unlimited voluntary feed intake. These characteristics cause many problems in the management of broiler breeder hens because of the negative correlation between muscle growth and reproduction effectiveness. 2. This problem, namely the fast muscle growth versus reproduction health paradox, induces a second paradox, acceptable reproduction and health versus hunger stress and impaired welfare, because broiler breeder hens require dedicated programmes of feed restriction (1) to maximise egg and chick production and (2) to avoid metabolic disorders and mortality in broiler breeders. 3. Given that poultry selection is a global large-scale business and chickens are a prolific species, improvement in profit can only be obtained by selecting on feed conversion and/or for higher breast meat percentage, which will intensify the broiler-breeder paradox. 4. New feeding strategies are being studied, but it is questionable if the paradox can be solved by management tools alone. Because breeding and selection are long-term processes, involving animals, farmers, consumers, industry, environment etc., a more sustainable breeding goal needs to be determined by a multidisciplinary approach and an open debate between several actors in the discussion. 5. Using dwarf broiler breeder hens could be one alternative, because dwarf hens combine relatively good reproductive fitness with ad libitum feeding. Another possibility is to accept lower broiler productivity by assigning economic values to welfare and including integrity traits in an extended breeding goal.

  13. Risk factors for Listeria monocytogenes contamination in French laying hens and broiler flocks.

    PubMed

    Aury, Kristell; Le Bouquin, Sophie; Toquin, Marie-Thérèse; Huneau-Salaün, Adeline; Le Nôtre, Yolène; Allain, Virginie; Petetin, Isabelle; Fravalo, Philippe; Chemaly, Marianne

    2011-03-01

    The objective of this study was to identify potential risk factors for Listeria monocytogenes contamination in French poultry production. Eighty-four flocks of layer hens kept in cages and 142 broiler flocks were included in this study. For each production type, a questionnaire was submitted to farmers and fecal samples were taken to assess the L. monocytogenes status of the flocks during a single visit to the farm. Two logistic regression models (specific to each production) were used to assess the association between management practices and the risk of L. monocytogenes contamination of the flock. The prevalence of L. monocytogenes-positive flocks was 30.9% (95% CI: 21.0; 40.9) and 31.7% (95% CI: 24.0; 39.4) for cage-layers and broiler flocks, respectively. For layer flocks, the risk of L. monocytogenes contamination was increased when pets were present on the production site. When droppings were evacuated by conveyor belt with deep pit storage, the risk of L. monocytogenes contamination decreased significantly. Feed meal was found to be associated with a higher risk of L. monocytogenes contamination than feed crumb. For broiler flocks, the risk of L. monocytogenes contamination was increased when farmers did not respect the principle of two areas (clean and dirty) at the poultry house entrance. A first disinfection by thermal fogging and the absence of pest control of the poultry house before the arrival of the next flock was found to increase the risk of contamination. When litter was not protected during storage and when farm staff also took care of other broiler chicken houses, the risk of L. monocytogenes contamination increased significantly. In the case of the watering system, nipples with cups were found to decrease the risk of contamination. PMID:21176855

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

    PubMed

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

    2006-03-01

    Emission of nitrogen in the form of ammonia from poultry rearing facilities has been an important topic for the poultry industry because of concerns regarding the effects of ammonia on the environment. Sound scientific data is needed to accurately estimate air emissions from poultry operations. Many factors, such as season of the year, ambient temperature and humidity, bird health, and management practices can influence ammonia volatilization from broiler rearing facilities. Precise results are often difficult to attain from commercial facilities, particularly over long periods of time. Therefore, an experiment was conducted to determine nitrogen loss from broilers in a research facility under conditions simulating commercial production for 18 consecutive flocks. Broilers were reared to 40 to 42 d of age and fed diets obtained from a commercial broiler integrator. New rice hulls were used for litter for the first flock, and the same litter was recycled for all subsequent flocks with caked litter removed between flocks. All birds, feeds, and litter materials entering and leaving the facility were quantified, sampled, and analyzed for total nitrogen content. Nitrogen loss was calculated by the mass balance method in which loss was equal to the difference between the nitrogen inputs and the nitrogen outputs. Nitrogen partitioning as a percentage of inputs averaged 15.29, 6.84, 55.52, 1.27, and 21.08% for litter, caked litter, broiler carcasses, mortalities, and nitrogen loss, respectively, over all eighteen flocks. During the production of 18 flocks of broilers on the same recycled litter, the average nitrogen emission rate was calculated to range from 4.13 to 19.74 g of N/ kg of marketed broiler (grams of nitrogen per kilogram) and averaged 11.07 g of N/kg. Nitrogen loss was significantly (P < 0.05) greater for flocks reared in summer vs. winter. Results of this experiment have demonstrated that the rate of nitrogen volatilization from broiler grow-out facilities

  15. Risk factors for Salmonella enterica subsp. enterica infection in senegalese broiler-chicken flocks.

    PubMed

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

    2004-05-14

    Our objective was to assess the association of managerial practices, general hygiene and Salmonella infection in Senegalese broiler flocks. Seventy broilers farms were studied from January 2000 to December 2001 around Dakar. A questionnaire was submitted to the farmers and samples of fresh broiler droppings were taken. A 28.6% of the flocks were infected by Salmonella (mainly Hadar and Brancaster serovars). Salmonella infection of the previous flock (OR = 6.82) and of day-old chicks (OR = 3.73), frequent poultry farmers' visits (OR = 5.38) and keeping sick birds inside the farm (OR = 5.32) increased the risk of Salmonella infection. But, using antibiotics on day-old chicks (OR = 0.17) and a detergent for cleaning (OR = 0.16) decreased the risk.

  16. Age effect of broiler breeders on fertility and sperm penetration of the perivitelline layer of the ovum.

    PubMed

    Gumułka, Małgorzata; Kapkowska, Ewa

    2005-11-01

    The objective of this study was to determine the age effect of a broiler breeder flock on duration of fertility and number of spermatozoa penetrating the perivitelline layer overlying the germinal disc (SP/mm(2) GDIPVL). Moreover, in the second half of the flock's reproductive life, the effect of using ejaculates of young roosters (CA2) in artificial insemination (AI) on the above parameters of fertility was estimated. The commercial flock of broiler breeder hens (n = 100) was inseminated six times from 31 to 62 weeks of age. Additional inseminations, with ejaculates of roosters aged 31 and 36 weeks (CA2), were performed at 56 and 62 weeks of age. AI was performed during two consecutive days (D0 and D1) with an insemination dose of 125 x 10(6) spermatozoa/0.06 ml containing pooled ejaculates. The following parameters were studied: the effective and maximum duration of fertility (De and Dm), percent of fertility on different days after AI (FD10, FD15 and FD20), indices of duration of sperm penetration (DSP, SP < or = 3/GDIPVL), SP/mm(2) GDIPVL in eggs laid on successive days after insemination of hens at different age, and correlations between some fertility indices. Both for De and Dm, the highest values were noted after AI of the layers at 36 weeks of age (14.8 +/- 0.49 and 17.4 +/- 0.46 days, respectively), which were about 2 days longer than at 56 weeks. All fertility indices decreased gradually with age, starting from AI at peak egg production (31-36 weeks of age), while the use of ejaculates from CA2 did not help to increase them significantly. Correlation coefficients between SP/mm(2) GDIPVL and the other fertility indices were positive and highest for eggs laid on D3. It is concluded that high De values can be obtained from broiler breeders in adequate environmental and technological conditions of AI. It is suggested that the age-related decrease in fertility is more pronounced in females, in which the efficiency of sperm storage tubules decreases. The

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

    PubMed

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

    2004-06-10

    Our objective was to identify the risk factors for Campylobacter infection in Senegalese broiler flocks. Seventy broiler farms were studied around Dakar from January 2000 to December 2001 around Dakar. A questionnaire was administered to the farmers, and samples of fresh droppings were taken to assess the flocks' Campylobacter status. About 63% of the flocks were infected by Campylobacter spp.; Campylobacter jejuni was the most-prevalent species (P < 0.05). An elevated risk of Campylobacter infection was associated with other animals (mainly laying hens, cattle and sheep) being bred in the farm, the farm staff not wearing their work clothing exclusively in the poultry houses, uncemented poultry-house floors and the use of cartons that transport chicks from the hatchery to the farm as feed plates (rather than specifically designed feed plates). Alternatively, thorough cleaning and disinfection of poultry-house surroundings and manure disposal outside the farm were associated with decreased flock risk.

  18. Prevalence and risk factors associated with campylobacter infections in broiler flocks in Shiraz, southern Iran.

    PubMed

    Ansari-Lari, Maryam; Hosseinzadeh, Saeid; Shekarforoush, S Shahram; Abdollahi, Mostafa; Berizi, Enayat

    2011-01-01

    Campylobacter species are among the most common bacterial causes of human gastroenteritis in many countries, and poultry meat is considered as a major source of human campylobacteriosis. The present study was conducted to determine the prevalence of infection by Campylobacter jejuni and Campylobacter coli in broiler flocks in Shiraz and to investigate the possible risk factors for the campylobacter infections in this area. For detection of campylobacter, multiplex polymerase chain reaction (mPCR) was used. Between August and September 2009, a total of 100 broiler flocks from 100 commercial broiler farms were selected at slaughter and campylobacter status was determined by mPCR on caecal samples. Data about farms and flocks were collected by questionnaires. Approximately 76% (95% CI: 67-84%) of the flocks were positive for C. jejuni or C. coli. Twenty two percent were positive for C. jejuni, 32% for C. coli and 22% for both species. Results of the statistical analysis using multivariable logistic regression showed that the odds of flock infection decreased when level of owner's education (years) increased (OR=0.86, P=0.04), also odds of infection was nearly five times higher when age at slaughter was ≥45 days compared with <45 days (OR=5.3, P=0.003) and use of antibiotic medications at early stage of production period was negatively associated with the infection status of the flock (OR=0.33, OR=0.059). We found no evidence of the effects of any other factors such as time interval between successive flocks, hygiene measures and number of broiler houses on the farm on the prevalence of campylobacter infection. Getting more attention to the health education issues and planning qualitative studies to reveal the behavioral aspects of the management policy, may be subjects of interest for future researches.

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

    PubMed

    Sandberg, M; Sørensen, L L; Steenberg, B; Chowdhury, S; Ersbøll, A K; Alban, L

    2015-03-01

    The objectives of the two studies presented were to estimate the prevalence of Campylobacter-positive farms and flocks and to acquire updated knowledge about risk factors for the introduction of Campylobacter in Danish broiler flocks. In the first study, from September 2010 to September 2011, there were 25 Danish broiler farms visited, and a questionnaire was filled in by a veterinarian/consultant. In the second study, a similar questionnaire was distributed electronically to all Danish broiler farmers (n=164) that were on record with an email address in the Quality Assurance System in the Danish Broiler Production (KIK) database. House- and flock-specific data collected in the surveys were supplemented with information obtained from the KIK database. Data obtained from the two studies were analyzed separately by logistic regression analysis. In both models, the dependent variable was "Campylobacter flock status (positive/negative)," which was based on real-time PCR testing of fecal material from the floor of each broiler house that had been collected preslaughter using a pair of tube gauze "socks." This material was pooled into one sample. Of the 25 farms visited, 17 had delivered Campylobacter-positive flocks during the study period, and eight farms had no Campylobacter-positive flocks. Moreover, the flock prevalence of Campylobacter was 17% (n=418). Data obtained from the electronically distributed survey revealed that 63% (n=71) of the farms were Campylobacter-positive. Further, the flock prevalence of Campylobacter was 14% (n=1,286). The multivariable models from the two sets of data identified the following statistically significant risk factors: summer vs. winter; if the previous flock in the house was positive for Campylobacter vs. if the previous flock in the house was negative; and litter delivered into the house close to the time of arrival of new chickens vs. storing litter on the farm. Furthermore, the data showed that a vertically based ventilation

  20. Effect of climatic variables on production and reproduction traits of colored broiler breeder poultry

    PubMed Central

    Nayak, G. D.; Behura, N. C.; Sardar, K. K.; Mishra, P. K.

    2015-01-01

    Aim: The present study was conducted to investigate the important climatic variables affecting production and reproduction in a broiler breeder flock. Materials and Methods: The experiment was conducted for a period of 1 year on colored synthetic female line male and female poultry birds. 630 female progeny and 194 male progenies from 69 sires and 552 dams produced in four consecutive hatches at an interval of 10 days were used for the present study. Each of the seven, body weight and reproduction traits were regressed with nine environmental variables. Initially, the data were subjected to hatch effect and sire effect corrections through best linear unbiased estimator (BLUE) method and, then, multiple linear regressions of environmental variables on each trait were applied. Result: The overall regression was significant (p<0.01) in all traits except 20 week age body weight of females. The R2 value ranged from 0.12 to 0.90 for the traits. Regression coefficient values (b values) for maximum temperature and minimum temperature were significant (p<0.05) on 5th week age body weight of males. Similarly, evaporation and morning relative humidity (RH) was significant (p<0.05) for 5th week age body weight of females. Almost all b values were significant (p<0.05) for egg production up to 40 week age. The b values representing rainfall, morning RH, afternoon RH, sunshine hours, and rainy days were significant (p<0.05) on bodyweight at 20 week age. All environmental variables except maximum temperature and minimum temperature were significant (p<0.05) on body weight of females at 20 weeks of age. Age at sexual maturity was regressed significantly (p<0.05) with evaporation, afternoon RH whereas, egg shape index was regressed significantly (p<0.05) with a maximum temperature, evaporation and afternoon RH. Conclusion: The result indicated that various environmental variables play a significant role in production and reproduction of breeder broiler poultry. Controlling these

  1. Poultry flocks as a source of Campylobacter contamination of broiler carcasses.

    PubMed

    Wieczorek, K; Osek, J

    2015-01-01

    Campylobacter infection is the leading foodborne bacterial gastroenteritis worldwide and the bacteria are frequently isolated from the intestines of chickens. The broiler meat contamination with C. jejuni or C. coli may occur during slaughter processing. The aim of the study was to investigate the prevalence of Campylobacter in poultry flocks and the corresponding broiler carcasses in 15 districts (voivodeships) all over Poland. A total of 128 samples from broiler flocks and the corresponding carcasses were collected between February 2011 and April 2013. The Campylobacter isolation and species identification were performed according to ISO 10272-1 standard and with PCR. It was found that 112 flock (96.5%) were contaminated with campylobacters, either C. jejuni (77 samples; 68.7%) or C. coli (35 flocks; 31.3%). Analysis of the corresponding chicken carcasses tested after chilling revealed that 77 out of 128 (60.2%) samples were positive for Campylobacter, either C. jejuni (58; 75.3%) or C. coli (19; 24.7%). Most of the carcasses were contaminated with the same Campylobacter species as identified in the corresponding flock before slaughter. As tested by PCR, out of the 77 crops with C. jejuni 58 were positive for the same bacterial species. On the other hand, out of the remaining 35 flocks infected with C. coli, only 19 corresponding carcass samples were contaminated with C. coli. In three cases in the slaughtered flocks C. jejuni was identified but in the same carcasses C. coli was found. The opposite findings (flock positive for C. coli but the corresponding carcasses contaminated with C. jejuni) were seen in six voivodeships. It was also observed that several carcass samples were negative for C. jejuni and C. coli although the original flocks were Campylobacter-positive before slaughter (total 36 of the 77 samples; 46.7%). On the other hand, some carcasses were contaminated with Campylobacter although the flocks were negative for these bacteria (9 samples; 11

  2. Molecular survey of avian respiratory pathogens in commercial broiler chicken flocks with respiratory diseases in Jordan.

    PubMed

    Roussan, D A; Haddad, R; Khawaldeh, G

    2008-03-01

    Acute respiratory tract infections are of paramount importance in the poultry industry. Avian influenza virus (AIV), infectious bronchitis virus (IBV), Newcastle disease virus (NDV), avian pneumovirus (APV), and Mycoplasma gallisepticum (MG) have been recognized as the most important pathogens in poultry. In this study, trachea swabs from 115 commercial broiler chicken flocks that suffered from respiratory disease were tested for AIV subtype H9N2, IBV, NDV, and APV by using reverse transcription PCR and for MG by using PCR. The PCR and reverse transcription PCR results showed that 13 and 14.8% of these flocks were infected with NDV and IBV, respectively, whereas 5.2, 6.0, 9.6, 10.4, 11.3, and 15.7% of these flocks were infected with both NDV and MG; MG and APV; IBV and NDV; IBV and MG; NDV and AIV; and IBV and AIV, respectively. Furthermore, 2.6% of these flocks were infected with IBV, NDV, and APV at the same time. On the other hand, 11.3% of these flocks were negative for the above-mentioned respiratory diseases. Our data showed that the above-mentioned respiratory pathogens were the most important causes of respiratory disease in broiler chickens in Jordan. Further studies are necessary to assess circulating strains, economic losses caused by infections and coinfections of these pathogens, and the costs and benefits of countermeasures. Furthermore, farmers need to be educated about the signs and importance of these pathogens.

  3. Isolation of Campylobacter from Brazilian broiler flocks using different culturing procedures.

    PubMed

    Vaz, C S L; Voss-Rech, D; Pozza, J S; Coldebella, A; Silva, V S

    2014-11-01

    Conventional culturing methods enable the detection of Campylobacter in broiler flocks. However, laboratory culture of Campylobacter is laborious because of its fastidious behavior and the presence of competing nontarget bacteria. This study evaluated different protocols to isolate Campylobacter from broiler litter, feces, and cloacal and drag swabs. Samples taken from commercial Brazilian broiler flocks were directly streaked onto Preston agar (PA), Campy-Line agar (CLA), and modified charcoal cefoperazone deoxycholate agar (mCCDA) and also enriched in blood-free Bolton broth (bfBB) for 24 and 48 h followed by plating onto the different selective media. Higher numbers of Campylobacter-positive cloacal and drag swab samples were observed using either direct plating or enrichment for 24 h before plating onto PA, compared with enrichment for 48 h (P < 0.05). Furthermore, direct plating was a more sensitive method to detect Campylobacter in broiler litter and feces samples. Analysis of directly plated samples revealed that higher Campylobacter levels were detected in feces streaked onto PA (88.8%), cloacal swabs plated onto mCCDA (72.2%), drag swabs streaked onto CLA or mCCDA (69.4%), and litter samples inoculated onto PA (63.8%). Preston agar was the best agar to isolate Campylobacter from directly plated litter samples (P < 0.05), but there was no difference in the efficacies of PA, mCCDA, and CLA in detecting Campylobacter in other samples. The isolated Campylobacter strains were phenotypically identified as Campylobacter jejuni or Campylobacter coli. The predominant contaminant observed in the Campylobacter cultures was Proteus mirabilis, which was resistant to the majority of antimicrobial agents in selective media. Together, these data showed that direct plating onto PA and onto either CLA or mCCDA as the second selective agar enabled the reliable isolation of thermophilic Campylobacter species from broiler samples. Finally, Campylobacter was detected in all

  4. Mating behavior and fertility of broiler breeder males reared on shortened growth cycles

    Technology Transfer Automated Retrieval System (TEKTRAN)

    One of the more difficult tasks when raising broiler breeder cockerels is controlling weight gain in the rearing house without inflicting excess stress. This is a period of time for the young male when many portions of reproductive system are in the formative stages and, if neglected, can have lif...

  5. Effects of restricted feeding on physiological stress parameters in growing broiler breeders.

    PubMed

    de Jong, I C; van Voorst, S; Ehlhardt, D A; Blokhuis, H J

    2002-05-01

    1. In previous studies, a lack of agreement in measurements of plasma corticosterone concentrations and heterophil:lymphocyte (H/L) ratio as physiological indices of stress, caused by hunger and frustration in restricted-fed broiler breeders, was observed. It could be suggested that the differences between previous studies were caused by differences in duration of restriction and time of the day of the measurements. Therefore, in the present study the plasma corticosterone concentration and the H/L ratio were again determined in restricted- and ad libitum-fed growing broiler breeders, taking possible causes of disagreement between previous studies into account. In addition, we measured the daily rhythm in body temperature and heart rate, and the corticosterone responses to an acute stressor as physiological indices of stress. 2. Female broiler breeders (64 per treatment, housed in groups of 4 birds) were used in the experiment. Behaviour, baseline plasma corticosterone concentrations and H/L ratio were determined at 21 d of age (immediately after the start of food restriction), and at 42 and 63 d of age. Body temperature, heart rate and activity were measured by radiotelemetry for 36 h at 49 and 70 d of age. In addition, the plasma corticosterone response to acute stress (5 min manual restraint) was measured at 77 or 78 d of age. 3. Restricted broiler breeders had higher plasma corticosterone concentrations at 42 and 63 d of age, but no differences in H/L. ratio were found between restricted birds and unrestricted control birds. Restricted broiler breeders had a higher corticosterone response to 5 min manual restraint than unrestricted birds. Restricted birds displayed a clear day-night rhythm in body temperature, heart rate and activity whereas such a rhythm was blunted in ad libitum-fed birds. 4. It is discussed that some physiological differences (plasma corticosterone concentrations, body temperature and heart rate) between ad libitum-fed and restricted broiler

  6. Unidentified Factors in Jojoba Meal Prevent Oviduct Development in Broiler Breeder Females.

    PubMed

    Vermaut; Onagbesan; Bruggeman; Verhoeven; Berghman; Flo; Cokelaere; Decuypere

    1998-01-19

    Supplementation of feed with jojoba meal, as a means for autonomous feed restriction, was successful in depressing feed intake and controlling body weight of broiler breeder pullets to the extent recommended by the breeder company. However, these broiler breeders never produced eggs. At the level of ovary, normal follicle development and maturation did occur. A considerable number of ovulations occurred which were not followed by oviposition. After ovulation, the ova could not be captured by the oviduct, because of the small size of the oviduct, resulting in "internal laying". The virtual absence of oviduct development cannot be explained presently but it must be due to some yet unidentified factor(s) in jojoba meal which prevent(s) the normal development of the oviduct. These factors may be acting by abnormally increasing plasma progesterone or triiodothyronin levels and/or directly by themselves interfering with oviduct development. The nature of these factors requires further investigations.

  7. Effects of environmental temperature and dietary energy on energy partitioning coefficients of female broiler breeders.

    PubMed

    Pishnamazi, A; Renema, R A; Paul, D C; Wenger, I I; Zuidhof, M J

    2015-10-01

    With increasing disparity between broiler breeder target weights and broiler growth potential, maintenance energy requirements have become a larger proportion of total broiler breeder energy intake. Because energy is partitioned to growth and egg production at a lower priority than maintenance, accurate prediction of maintenance energy requirements is important for practical broiler breeder feed allocation decisions. Environmental temperature affects the maintenance energy requirement by changing rate of heat loss to the environment. In the ME system, heat production (energy lost) is part of the maintenance requirement (ME). In the current study, a nonlinear mixed model was derived to predict ME partitioning of broiler breeder hens under varied temperature conditions. At 21 wk of age, 192 Ross 708 hens were individually caged within 6 controlled environmental chambers. From 25 to 41 wk, 4 temperature treatments (15°C, 19°C, 23°C, and 27°C) were randomly assigned to the chambers for 2-week periods. Half of the birds in each chamber were fed a high-energy (HE; 2,912 kcal/kg) diet, and half were fed a low-energy (LE; 2,790 kcal/kg) diet. The nonlinear mixed regression model included a normally distributed random term representing individual hen maintenance, a quadratic response to environmental temperature, and linear ADG and egg mass (EM) coefficients. The model assumed that energy requirements for BW gain and egg production were not influenced by environmental temperature because hens were homeothermic, and the cellular processes for associated biochemical processes occurred within a controlled narrow core body temperature range. Residual feed intake (RFI) and residual ME (RME) were used to estimate efficiency. A quadratic effect of environmental temperature on broiler breeder MEm was predicted ( < 0.0001), with a minimum energy expenditure at 24.3°C. Predicted ME at 21°C was 92.5 kcal/kg; requirements for gain and EM were 2.126 and 1.789 kcal/g, respectively

  8. Effect of the ratio of dietary n-3 fatty acids eicosapentaenoic acid and docosahexaenoic acid on broiler breeder performance, egg quality, and yolk fatty acid composition at different breeder ages.

    PubMed

    Koppenol, A; Delezie, E; Aerts, J; Willems, E; Wang, Y; Franssens, L; Everaert, N; Buyse, J

    2014-03-01

    When added to the feed of broiler breeder hens, dietary polyunsaturated fatty acids (FA) can be incorporated into the yolk and therefore become available to the progeny during their early development. The mechanism involved in lipid metabolism and deposition in the egg may be influenced by breeder age. Before the effect of an elevated concentration of certain polyunsaturated FA on the embryo can be investigated, the effect at breeder level and egg quality must be further assessed. The aim of the present experiment was to evaluate the effects of dietary n-6/n-3 ratios and dietary eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3) ratios, provided to broiler breeder hens, in terms of their zoo technical performance, egg quality, and yolk FA composition. Starting at 6 wk of age, 640 Ross-308 broiler breeder hens were fed 1 of 4 different diets. The control diet was a basal diet, rich in n-6 FA. The 3 other diets were enriched in n-3 FA, formulated to obtain a different EPA/DHA ratio of 1/1 (EPA = DHA), 1/2 (DHA), or 2/1 (EPA). In fact, after analysis the EPA/DHA ratio was 0.8, 0.4, or 2.1, respectively. Dietary EPA and DHA addition did not affect the performance of the breeder hens, except for egg weight. Egg weight was lower (P < 0.001) for all n-3 treatments. Dietary EPA improved number of eggs laid in the first 2 wk of the production cycle (P = 0.029). The absolute and relative yolk weight of eggs laid by EPA = DHA fed hens was lowest (P = 0.004 and P = 0.025, respectively). The EPA and DHA concentrations in the yolk were highly dependent on dietary EPA and DHA concentrations with a regression coefficient equal to 0.89. It can be concluded that dietary EPA and DHA can be incorporated in the breeder egg yolk to become available for the developing embryo, without compromising the performance and egg quality of the flock.

  9. Multilevel analysis of environmental Salmonella prevalences and management practices on 49 broiler breeder farms in four south-eastern States, USA.

    PubMed

    Berghaus, R D; Mathis, D L; Bramwell, R K; Macklin, K S; Wilson, J L; Wineland, M J; Maurer, J J; Lee, M D

    2012-08-01

    A two-part serial survey of 49 broiler breeder farms was conducted in four south-eastern states: Arkansas, Alabama, Georgia and North Carolina. Broiler breeder farms from three to five broiler company complexes in each state were visited on two separate occasions to document management practices and perform environmental sampling for Salmonella prevalence estimation. Salmonella was detected in 88% of the broiler breeder houses that were sampled and was identified on all 49 farms enrolled. Many management characteristics were consistent across the different states and companies. Multilevel analysis was used to evaluate management characteristics as risk factors for Salmonella prevalence and to estimate the proportion of variance residing at the different hierarchical sampling levels. Management characteristics associated with increased Salmonella prevalence included treatment of the flock for any disease, having dusty conditions in the house, having dry conditions under the slats and walking through the house more than one time per day to pick-up dead birds. After adjusting for state as a fixed effect, the percentages of variance in Salmonella prevalence occurring at the complex, farm, visit, house and individual sample levels were 5.2%, 6.8%, 11.8%, 2.8% and 73.4%, respectively. The intraclass correlations for samples collected from the same house; for samples from different houses during the same visit; for samples from different visits to the same farm; and for samples from different farms in the same complex were as follows: 0.27, 0.24, 0.12 and 0.05, respectively.

  10. Effects of incubational humidity and hen age on embryo composition in broiler hatching eggs from young breeders.

    PubMed

    Peebles, E D; Burnham, M R; Gardner, C W; Brake, J; Bruzual, J J; Gerard, P D

    2001-09-01

    There is a paucity of information regarding the influence of incubational humidity on the characteristics of broiler embryos from young hens that often produce chicks of marginal quality. Therefore, the effects of broiler breeder age (26, 28, and 30 wk) in young broiler breeders and incubator humidity (43, 53, and 63% RH) on embryonic growth between 16 and 21 d of incubation, hatching chick weight, and embryo and chick body compositions were evaluated. Hatching broiler chick BW at 21 d was lower for 26-wk-old breeders compared to those at 28 and 30 wk, and the lowest RH decreased relative wet embryo weight. Embryonic growth, on wet and DM bases, was increased in eggs from the youngest hens. Embryo moisture content (EM) was lower at 16, 17, and 19 d of incubation in eggs from breeders at 26 wk when compared to those at 28 wk of age. The effects of RH on embryo crude protein and fat composition were not consistent and varied with breeder age and length of incubation. It was demonstrated that broiler breeder age affects embryogenesis and hatching chick BW. Furthermore, EM was influenced by breeder age, and changes in incubational RH between 43 and 63% affected embryogenesis without having associated effects on EM or consistent effects on embryo crude fat and protein content. Nevertheless, a depression in embryogenesis with a reduction in incubational RH to 43% may accentuate poor posthatch performance of chicks from young breeders.

  11. Illuminance, sexual maturation, and early egg production in female broiler breeders.

    PubMed

    Lewis, P D; Danisman, R; Gous, R M

    2008-11-01

    1. Broiler breeders were reared at an initial illuminance of 13, 21 or 44 lux and transferred at 20 weeks and a mean body weight of 2.06 kg to floor pens at 25, 55 or 71 lux, or to individual cages at various intensities between 3 and 138 lux. 2. Rate of sexual maturation was not significantly affected by the light intensity experienced during the rearing period, but was progressively accelerated by the provision of a brighter illuminance after 20 weeks, up to a ceiling of about 14 lux. There was no interaction between the pre- and post-20-week illuminance. 3. Cumulative egg numbers to 39 weeks were unaffected by illuminance in the rearing period, positively correlated with illuminance post 20 weeks up to an asymptote at about 8 lux, and highly correlated with age at sexual maturity. Peak rate of lay was both delayed and depressed at 3 lux. 4. It is concluded that the minimum light intensity required at bird-head height to achieve satisfactory photostimulation and an optimal peak rate of lay in broiler breeders is 10 lux, but that a higher illuminance would be prudent for broiler breeders kept in floor pen facilities to maximise nest-box usage.

  12. Comparison of Campylobacter populations isolated from a free-range broiler flock before and after slaughter

    PubMed Central

    Colles, Frances M.; McCarthy, Noel D.; Sheppard, Samuel K.; Layton, Ruth; Maiden, Martin C.J.

    2014-01-01

    Relatively little is known about the Campylobacter genotypes colonizing extensively reared broiler flocks and their survival through the slaughter process, despite the increasing demand for free-range and organic products by the consumer. Campylobacter isolates from a free-range boiler flock, sampled before and after slaughter, were genotyped by MLST (multilocus sequence typing) and sequence analysis of the flaA short variable region (SVR). The Campylobacter genotypes isolated before and after slaughter were diverse, with up to five sequence types (STs) (seven-locus allelic profiles resulting from MLST) identified per live bird, up to eight STs identified per carcass and 31 STs identified in all. The majority (72.0%) of isolates sampled from carcasses post-slaughter were indistinguishable from those isolated from the live flock before slaughter by ST and flaA SVR type, however, sampling ‘on-farm’ failed to capture all of the diversity seen post-slaughter. There were statistically significant increases in the genetic diversity of Campylobacter (p=0.005) and the proportion of C. coli (p=0.002), with some evidence for differential survival of genotypes contaminating the end product. C. coli genotypes isolated after slaughter were more similar to those from free-range and organic meat products sampled nationally, than from the live flock sampled previously. This study demonstrated the utility of MLST in detecting genetic diversity before and after the slaughter process. PMID:20071049

  13. Relationships between fertility and some parameters in male broiler breeders (body and testicular weight, histology and immunohistochemistry of testes, spermatogenesis and hormonal levels).

    PubMed

    Sarabia Fragoso, J; Pizarro Díaz, M; Abad Moreno, J C; Casanovas Infesta, P; Rodriguez-Bertos, A; Barger, K

    2013-04-01

    In a farm of grandparent broiler breeder chickens, we followed the development of 350 roosters from 6 to 55 weeks of age. Data collected and evaluated from these males included body weight, testicular weight, histologic and immunohistochemistry studies of the testes, hormone levels (testosterone, estradiol and corticosterone) and sperm production. The objective was to understand the factors that affect or influence hatch loss that is commonly observed after 45 weeks of age in breeder flocksare often correlated to broiler breeder male chickens. The results of this study showed that in conjunction with the weight of the rooster, the testicle weight increases quickly after the rooster receives light stimulation. At an older age, the study showed that there is a process of testicular shrinkage, and the same effect is seen in sperm production and testosterone levels in broiler breeder roosters. From the histology evaluation, we defined 5 histologic phases that illustrate the evolution of the testicular tissue: perinatal, infantile, puberty, adult and senile. We observed that the adult males with a body weight <3800 g were infertile or had subfertile levels and also had low levels of testosterone and high levels of corticosterone. In contrast, the heaviest males showed correct testicular vitality, high levels of testosterone and low levels of corticosterone. However, the roosters that had acquired this high body weight were also at risk of having less complete copulations because of their physical mass. The loss of uniformity of the males and the appearance of hierarchies within the flock accompany a decline in the percentages of hatches as a consequence of the poor confirmation of the males for copulation or the restriction to the access to the females. Results of this study show that the decrease in fertility from 45 weeks of age has been associated with a decline in testicular weight, sperm production and the testosterone levels in animals with a sub-par weight

  14. Effect of day length on flock behavioural patterns and melatonin rhythms in broilers.

    PubMed

    Schwean-Lardner, K; Fancher, B I; Laarveld, B; Classen, H L

    2014-02-01

    1. Ross × Ross 308 male broilers were used to study the impact of 14, 17, 20 and 23 h of light (L) on flock behavioural patterns and 24 h melatonin rhythm synchrony during the photophase. 2. Behaviour in two pens (n = 53) per lighting treatment was digitally recorded for 24 h in trial 1 (27-28 d of age (d 27)) and two (42-43 d (d 42)), and quantified using a scan sampling technique at 10 min intervals. Regression procedures were used to test flock trend analysis between behavioural (resting, standing, walking and feeding) variables and time during the photophase. 3. The presence of a flock melatonin rhythm was determined by radioimmunoassay of blood samples collected at 6 times for birds raised on 23L and 8 times for 14, 17 and 20L birds (n = 6 per time) over a 24 h period (d 21) in experiment 1. 4. Quadratic and linear relationships between time and behaviour during the photophase were frequent in 14L and 17L birds, sporadic in 20L birds and non-existent in 23L birds. Relationships were noted in inactive resting (d 27: 14L and 17L; d 42: 14L and 20L), walking (d 27: 14L and 17L), standing (d 27 and d 42: 14L, 17L and 20L) and feeding (d 27: 14L and 17L). A quadratic time × melatonin relationship existed in 14L, 17L and 20L flocks only. 5. Behaviour during the photophase and 24 h melatonin production indicates that flocks exposed to 23L do not develop synchronised rhythms, increasing the risk of suffering from sleep fragmentation.

  15. The relationships of salmonellae from infected broiler flocks, transport crates or processing plants to contamination of eviscerated carcases.

    PubMed Central

    Rigby, C E; Pettit, J R; Bentley, A H; Spencer, J L; Salomons, M O; Lior, H

    1982-01-01

    Three flocks raised for broiler or roaster performance tests were studied to determine the incidence and sources of salmonellae during the growing period, transport and processing and to relate these to contamination of processed carcasses. Day old chicks in two of the tests, (tests IV and V), were treated with a culture of intestinal anaerobes derived from mature chickens. The incidence of salmonellae during the growing period was too low to permit any conclusions about the efficacy of this culture in preventing Salmonella infection, but it had no adverse effect on flock performance. Carcasses from all three flocks were contaminated with salmonellae. Although the test IV flock was raised free of salmonellae, 46% of the carcasses tested from this flock were contaminated. The apparent source was the transport crates, 99% of which yielded salmonellae before the flock was loaded. In test V, 92% of the carcasses tested yielded salmonellae. The apparent sources were: flock infection (apparently originating from the parent flock), contaminated crates, spread during transport, and plant contamination. The flock of test VI was infected with Salmonella albany, and 54% of the carcasses tested were contaminated with this serovar. Carcasses of chicks infected early in life were more likely to be contaminated than those of chickens which contacted salmonellae later in the growing period. PMID:7127193

  16. A pharmaco-epidemiological analysis of factors associated with antimicrobial consumption level in turkey broiler flocks.

    PubMed

    Chauvin, Claire; Bouvarel, Isabelle; Beloeil, Pierre-Alexandre; Orand, Jean-Pierre; Guillemot, Didier; Sanders, Pascal

    2005-01-01

    An on-farm pharmaco-epidemiological survey of 246 turkey broiler flocks from 131 farms was carried out to assess the homogeneity of antimicrobial use between flocks on the same farm and to explore the possible relationships between farm and farmer characteristics and the level of antimicrobial use. The antimicrobial use in each flock was quantified by an invoice study, expressed as the number of national animal daily doses (ADD)/turkey broiler and characterised as "high", "medium" or "low" according to the tertiles of the resulting distribution. Antimicrobial use was then correlated with variables collected from the farmer by means of an alternating logistic regression method which calculates the pairwise odds ratio (PWOR) for within-farm clustering. Two independent models were fitted: (1) "low" versus "medium" + "high" antimicrobial consumption and (2) "high" versus "medium" + "low" antimicrobial consumption. PWOR from the null models were significant (P < 0.005), but only remained significant in the first final model (P = 0.002). Four explanatory variables were retained for both models. Prophylactic antimicrobial administration and veterinarian antimicrobial prescription attaining the farm technical staff's expectation were associated with a higher antimicrobial consumption level. Administration of competitive exclusion flora and compliance with biosecurity rules of changing clothes and shoes before entering the facilities, were associated with a lower antimicrobial consumption level. In the first model, the number of full-time jobs devoted to the turkey production unit (1 versus more than 1) was also found to be associated with the antimicrobial consumption level. The study tends to confirm the feasibility of the adopted approach to quantify antimicrobial use and to determine the factors likely to influence antimicrobial consumption. PMID:15720973

  17. Research on Salmonella in broiler litter reused for up to 14 consecutive flocks.

    PubMed

    Roll, V F B; Dai Prá, M A; Roll, A P

    2011-10-01

    The reuse of poultry litter is a common practice in the Brazilian poultry industry for flocks of healthy chickens, due to 2 fundamental aspects: production cost and environmental sustainability. Litter is a potentially important source of infection for Salmonella, which requires characterization by microbiological analysis in different aspects of management and reuse. The objective of this study was to verify the occurrence of Salmonella in broiler litters reused up to 14 times in Brazilian poultry farms. From January 2008 to November 2010, 8,877 samples of litter on disposable shoe covers were analyzed from broiler farms located in southern Brazil. At the laboratory, samples were processed for isolation and identification of Salmonella. Of the total 8,877 samples analyzed, only 2.5, 5.27, and 2.08% were positive for Salmonella in the years 2008, 2009, and 2010, respectively. Linear regression models indicate that there is a significant decrease (P < 0.05) in the count of samples positive for Salmonella with the reuse of litter. After the sixth reuse of the litter, values of samples positive for Salmonella are significantly (P < 0.0001) lower than expected (chi-squared test). Results show that the reuse of treated broiler litter is a safe practice and contrary to expectations, it substantially decreases the bacterial load of Salmonella.

  18. Effect of dietary vitamin A on reproductive performance and immune response of broiler breeders.

    PubMed

    Yuan, Jianmin; Roshdy, Abdelfatah Rashad; Guo, Yuming; Wang, Yongwei; Guo, Shuangshuang

    2014-01-01

    The effects of dietary vitamin A supplementation on reproductive performance, liver function, fat-soluble vitamin retention, and immune response were studied in laying broiler breeders. In the first phase of the experiment, 1,120 Ross-308 broiler breeder hens were fed a diet of corn and soybean meal supplemented with 5,000 to 35,000 IU/kg vitamin A (retinyl acetate) for 20 weeks. In the second phase, 384 Ross-308 broiler breeder hens were fed the same diet supplemented with 5,000 to 135,000 IU/kg vitamin A (retinyl acetate) for 24 weeks. The hens' reproductive performance, the concentrations of vitamins A and E in liver and egg yolk, liver function, mRNA expression of vitamin D receptor in duodenal mucosa, antibody titers against Newcastle disease virus vaccine, and T-cell proliferation responses were evaluated. Supplementation of vitamin A at levels up to and including 35,000 IU/kg did not affect reproductive performance and quadratically affected antibody titer to Newcastle disease virus vaccine (p<0.05). Dietary addition of vitamin A linearly increased vitamin A concentration in liver and yolk and linearly decreased α-, γ-, and total tocopherol concentration in yolk (p<0.01) and α-tocopherol in liver (p<0.05). Supplementation of vitamin A at doses of 45,000 IU/kg and above significantly decreased egg weight, yolk color, eggshell thickness and strength, and reproductive performance. Dietary vitamin A significantly increased mRNA expression of vitamin D receptor in duodenal mucosa (p<0.05), increased aspartate amino transferase activity, and decreased total bilirubin concentration in serum. Supplementation of vitamin A at 135,000 IU/kg decreased the proliferation of peripheral blood lymphocytes (p<0.05). Therefore, the maximum tolerable dose of vitamin A for broiler breeders appears to be 35,000 IU/kg, as excessive supplementation has been shown to impair liver function, reproductive performance, and immune response. PMID:25148198

  19. Role of the serotonergic axis in the reproductive failure associated with aging broiler breeder roosters.

    PubMed

    Avital-Cohen, N; Heiblum, R; Rosenstrauch, A; Chaiseha, Y; Mobarkey, N; Gumułka, M; Rozenboim, I

    2015-10-01

    Reproductive failure associated with aging is a well-known phenomenon. However, the mechanism by which this failure occurs in broiler breeder roosters is still unclear. A previous study conducted in our laboratory, comparing young and aging broiler breeder roosters, demonstrated an elevation in hypothalamic vasoactive intestinal peptide (VIP) and pituitary prolactin (PRL) gene expression accompanied by a deterioration of gonadal axis function. This resulted in a decrease in semen-quality variables as roosters aged. The objective of this study was to examine the involvement of the serotonergic axis in the age-associated reproductive failure in broiler breeder roosters. Cobb roosters aged 64 wk were divided into 3 groups (n = 20 each): parachlorophenylalanine (PCPA) administration, active immunization against chicken VIP, and controls. At 69 wk of age, each group was divided into 2 equal subgroups: 1 received ovine PRL and the other served as controls. Weekly semen volume, concentration and motility, and plasma testosterone, estradiol, and PRL concentrations were examined. At the end of the experiment, roosters were euthanized, testes were weighed, and hypothalamus and pituitary were removed to assay the expression of genes encoding hypothalamic GnRH-I, pituitary FSH, pituitary LH, hypothalamic VIP, and pituitary PRL. Both PCPA administration and active immunization against chicken VIP significantly increased testis weight, semen volume, sperm concentration, ejaculation grade, plasma testosterone level, and GnRH-I, FSH and LH gene expression compared with controls (P ≤ 0.05). In addition, a decrease in plasma estradiol and PRL concentrations and VIP and PRL gene expression was observed in PCPA- and VIP-immunized birds compared with controls (P ≤ 0.05). Administration of PRL in all groups decreased gonadal axis function and semen-quality variables (P ≤ 0.05). Collectively, these results suggest that the increasing expression levels of the serotonergic axis

  20. Effect of dietary vitamin A on reproductive performance and immune response of broiler breeders.

    PubMed

    Yuan, Jianmin; Roshdy, Abdelfatah Rashad; Guo, Yuming; Wang, Yongwei; Guo, Shuangshuang

    2014-01-01

    The effects of dietary vitamin A supplementation on reproductive performance, liver function, fat-soluble vitamin retention, and immune response were studied in laying broiler breeders. In the first phase of the experiment, 1,120 Ross-308 broiler breeder hens were fed a diet of corn and soybean meal supplemented with 5,000 to 35,000 IU/kg vitamin A (retinyl acetate) for 20 weeks. In the second phase, 384 Ross-308 broiler breeder hens were fed the same diet supplemented with 5,000 to 135,000 IU/kg vitamin A (retinyl acetate) for 24 weeks. The hens' reproductive performance, the concentrations of vitamins A and E in liver and egg yolk, liver function, mRNA expression of vitamin D receptor in duodenal mucosa, antibody titers against Newcastle disease virus vaccine, and T-cell proliferation responses were evaluated. Supplementation of vitamin A at levels up to and including 35,000 IU/kg did not affect reproductive performance and quadratically affected antibody titer to Newcastle disease virus vaccine (p<0.05). Dietary addition of vitamin A linearly increased vitamin A concentration in liver and yolk and linearly decreased α-, γ-, and total tocopherol concentration in yolk (p<0.01) and α-tocopherol in liver (p<0.05). Supplementation of vitamin A at doses of 45,000 IU/kg and above significantly decreased egg weight, yolk color, eggshell thickness and strength, and reproductive performance. Dietary vitamin A significantly increased mRNA expression of vitamin D receptor in duodenal mucosa (p<0.05), increased aspartate amino transferase activity, and decreased total bilirubin concentration in serum. Supplementation of vitamin A at 135,000 IU/kg decreased the proliferation of peripheral blood lymphocytes (p<0.05). Therefore, the maximum tolerable dose of vitamin A for broiler breeders appears to be 35,000 IU/kg, as excessive supplementation has been shown to impair liver function, reproductive performance, and immune response.

  1. Effect of Dietary Vitamin A on Reproductive Performance and Immune Response of Broiler Breeders

    PubMed Central

    Guo, Yuming; Wang, Yongwei; Guo, Shuangshuang

    2014-01-01

    The effects of dietary vitamin A supplementation on reproductive performance, liver function, fat-soluble vitamin retention, and immune response were studied in laying broiler breeders. In the first phase of the experiment, 1,120 Ross-308 broiler breeder hens were fed a diet of corn and soybean meal supplemented with 5,000 to 35,000 IU/kg vitamin A (retinyl acetate) for 20 weeks. In the second phase, 384 Ross-308 broiler breeder hens were fed the same diet supplemented with 5,000 to 135,000 IU/kg vitamin A (retinyl acetate) for 24 weeks. The hens' reproductive performance, the concentrations of vitamins A and E in liver and egg yolk, liver function, mRNA expression of vitamin D receptor in duodenal mucosa, antibody titers against Newcastle disease virus vaccine, and T-cell proliferation responses were evaluated. Supplementation of vitamin A at levels up to and including 35,000 IU/kg did not affect reproductive performance and quadratically affected antibody titer to Newcastle disease virus vaccine (p<0.05). Dietary addition of vitamin A linearly increased vitamin A concentration in liver and yolk and linearly decreased α-, γ-, and total tocopherol concentration in yolk (p<0.01) and α-tocopherol in liver (p<0.05). Supplementation of vitamin A at doses of 45,000 IU/kg and above significantly decreased egg weight, yolk color, eggshell thickness and strength, and reproductive performance. Dietary vitamin A significantly increased mRNA expression of vitamin D receptor in duodenal mucosa (p<0.05), increased aspartate amino transferase activity, and decreased total bilirubin concentration in serum. Supplementation of vitamin A at 135,000 IU/kg decreased the proliferation of peripheral blood lymphocytes (p<0.05). Therefore, the maximum tolerable dose of vitamin A for broiler breeders appears to be 35,000 IU/kg, as excessive supplementation has been shown to impair liver function, reproductive performance, and immune response. PMID:25148198

  2. Organic trace minerals (Mintrex P) in broiler breeder diets and pre-incubation conditions on bone development and leg health of broilers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Leg health issues and bone disorders are developmental problems that may be increased by environmental stress, inadequate nutrition, and improper incubation conditions. Organic trace minerals (OTM) as Mintrex® P were added on top (1 kg/MT) of Ross 708 broiler breeder diets from start of lay. Eggs fr...

  3. Effects of feeding grains naturally contaminated with Fusarium mycotoxins on performance and metabolism of broiler breeders.

    PubMed

    Yegani, M; Smith, T K; Leeson, S; Boermans, H J

    2006-09-01

    A study was conducted to investigate the effects of feeding grains naturally contaminated with Fusarium mycotoxins on performance and metabolism of broiler breeders. Forty-two 26-wk-old broiler breeder hens and nine 26-wk-old roosters were fed the following diets: (1) control, (2) contaminated grains, and (3) contaminated grains + 0.2% polymeric glucomannan mycotoxin adsorbent (GMA) for 12 wk. The major contaminant was deoxynivalenol (12.6 mg/kg of feed), with lesser amounts of zearalenone and 15-acetyl-deoxynivalenol. Feed consumption and BW were not affected by diet. The feeding of contaminated grains did not significantly affect egg production. Decreased eggshell thickness was seen, however, at the end of wk 4, and dietary supplementation with GMA prevented this effect. There was no effect of diet on other egg parameters measured. There was a significant increase in early (1 to 7 d) embryonic mortality in eggs from birds fed contaminated grains at wk 4, but mid- (8 to 14 d) and late- (15 to 21 d) embryonic mortalities were not affected by diet. There were no differences in newly hatched chick weights or viability. The ratio of chick weight to egg weight was not affected by the feeding of contaminated grains. Weight gains of chicks fed a standard broiler starter diet at 7, 14, and 21 d of age were not significantly affected by previous dietary treatments for the dam. It was found that rooster semen volume and sperm concentration, viability, and motility were not affected by the feeding of contaminated diets. There was no effect of diet on the relative weights of liver, spleen, kidney, and testes. The feeding of contaminated grains decreased antibody titers against infectious bronchitis virus at the end of wk 12, and this was prevented by dietary supplementation with GMA. There was no effect of the diet on serum antibody titers against Newcastle disease virus. It was concluded that the feeding of blends of grains contaminated with Fusarium mycotoxins could affect

  4. Sources of salmonellae in an uninfected commercially-processed broiler flock.

    PubMed Central

    Rigby, C E; Pettit, J R; Baker, M F; Bentley, A H; Salomons, M O; Lior, H

    1980-01-01

    Cultural monitoring was used to study the incidence and sources of salmonellae in a 4160 bird broiler flock during the growing period, transport and processing in a commercial plant. No salmonellae were isolated from any of 132 litter samples of 189 chickens cultured during the seven-week growing period, even though nest litter samples from four of the eight parent flocks yielded salmonellae and Salmonella worthington was isolated from the meat meal component of the grower ration. On arrival at the plant, 2/23 birds sampled carried S. infantis on their feathers, although intestinal cultures failed to yield salmonellae. Three of 18 processed carcasses samples yielded salmonellae (S. infantis, S. heidelberg, S. typhimurium var copenhagen). The most likely source of these salmonellae was the plastic transport crates, since 15/107 sampled before the birds were loaded yielded salmonellae (S. infantis, S. typhimurium). The crate washer at the plant did not reduce the incidence of Salmonella-contaminated crates, since 16/116 sampled after washing yielded salmonellae (S. infantis, S. typhimurium, S. heidelberg, S. schwarzengrund, S. albany). PMID:7427774

  5. Infectious bronchitis virus in different avian physiological systems-a field study in Brazilian poultry flocks.

    PubMed

    Balestrin, Eder; Fraga, Aline P; Ikuta, Nilo; Canal, Cláudio W; Fonseca, André S K; Lunge, Vagner R

    2014-08-01

    Avian infectious bronchitis is a highly contagious viral disease with economic effects on poultry agribusiness. The disease presents multi-systemic clinical signs (respiratory, renal, enteric, and reproductive) and is caused by one coronavirus (infectious bronchitis virus, IBV). Infectious bronchitis virus is classified into different serotypes and genotypes (vaccine strains and field variants). This study aimed to evaluate the occurrence of IBV in commercial poultry flocks from 3 important producing regions in Brazil and to determine the tropism of the main circulating genotypes to 3 different avian physiological systems (respiratory, digestive, urinary/reproductive). Clinical samples with suggestive signs of IBV infection were collected from 432 different poultry commercial flocks (198 from broilers and 234 from breeders). The total number of biological samples consisted of organ pools from the 3 above physiological systems obtained of farms from 3 important producing regions: midwest, northeast, and south. Infectious bronchitis virus was detected by reverse-transcription, real-time PCR of the 5' untranslated region. The results showed 179 IBV-positive flocks (41.4% of the flocks), with 107 (24.8%) from broilers and 72 (16.8%) from breeders. There were similar frequencies of IBV-positive flocks in farms from different regions of the country, most often in broilers (average 54%) compared with breeders (average 30.8%). reverse-transcription was more frequently detected in the digestive system of breeders (40%), and in the digestive (43.5%) and respiratory (37.7%) systems of broilers. Infectious bronchitis virus genotyping was performed by a reverse-transcription nested PCR and sequencing of the S1 gene from a selection of 79 IBV-positive flocks (45 from broilers and 34 from breeders). The majority of the flocks were infected with Brazilian variant genotype than with Massachusetts vaccine genotype. These results demonstrate the predominance of the Brazilian variant

  6. Assessment of welfare of Brazilian and Belgian broiler flocks using the Welfare Quality protocol.

    PubMed

    Tuyttens, F A M; Federici, J F; Vanderhasselt, R F; Goethals, K; Duchateau, L; Sans, E C O; Molento, C F M

    2015-08-01

    The Welfare Quality consortium has proposed a science-based protocol for assessing broiler chicken welfare on farms. Innovative features make the protocols particularly suited for comparative studies, such as the focus on animal-based welfare measures and an integration procedure for calculating an overall welfare status. These protocols reflect the scientific status up to 2009 but are meant to be updated on the basis of inter alia implementation studies. Because only few such studies have been done, we applied the Welfare Quality protocol to compare the welfare of broiler flocks in Belgium (representing a typical European Union (EU) country which implies stringent animal welfare legislation) versus Brazil (the major broiler meat exporter to the EU and with minimal animal welfare legislation). Two trained observers performed broiler Welfare Quality assessments on a total of 22 farms in Belgium and south Brazil. All of the farms produced for the EU market. Although the overall welfare was categorized as 'acceptable' on all farms, many country differences were observed at the level of the welfare principles, criteria, and measures. Brazilian farms obtained higher scores for 3 of the 4 welfare principles: 'good feeding' (P = 0.007), 'good housing' (P < 0.001), and 'good health' (P = 0.005). Four of the 10 welfare criteria scores were, or tended to be, higher on Brazilian than Belgian farms: 'absence of prolonged thirst' (P < 0.001), 'ease of movement' (P < 0.001), 'absence of injuries' (P = 0.002), and 'positive emotional state' (P = 0.055). The only criteria with a higher score for the Belgian farms than their Brazilian counterparts were 'absence of prolonged hunger' (P = 0.048) and 'good human-animal relationship' (P = 0.002). Application of the Welfare Quality protocol has raised several concerns about the validity, reliability, and discriminatory potential of the protocol. The results also call for more research into the effect of animal welfare

  7. Assessment of welfare of Brazilian and Belgian broiler flocks using the Welfare Quality protocol.

    PubMed

    Tuyttens, F A M; Federici, J F; Vanderhasselt, R F; Goethals, K; Duchateau, L; Sans, E C O; Molento, C F M

    2015-08-01

    The Welfare Quality consortium has proposed a science-based protocol for assessing broiler chicken welfare on farms. Innovative features make the protocols particularly suited for comparative studies, such as the focus on animal-based welfare measures and an integration procedure for calculating an overall welfare status. These protocols reflect the scientific status up to 2009 but are meant to be updated on the basis of inter alia implementation studies. Because only few such studies have been done, we applied the Welfare Quality protocol to compare the welfare of broiler flocks in Belgium (representing a typical European Union (EU) country which implies stringent animal welfare legislation) versus Brazil (the major broiler meat exporter to the EU and with minimal animal welfare legislation). Two trained observers performed broiler Welfare Quality assessments on a total of 22 farms in Belgium and south Brazil. All of the farms produced for the EU market. Although the overall welfare was categorized as 'acceptable' on all farms, many country differences were observed at the level of the welfare principles, criteria, and measures. Brazilian farms obtained higher scores for 3 of the 4 welfare principles: 'good feeding' (P = 0.007), 'good housing' (P < 0.001), and 'good health' (P = 0.005). Four of the 10 welfare criteria scores were, or tended to be, higher on Brazilian than Belgian farms: 'absence of prolonged thirst' (P < 0.001), 'ease of movement' (P < 0.001), 'absence of injuries' (P = 0.002), and 'positive emotional state' (P = 0.055). The only criteria with a higher score for the Belgian farms than their Brazilian counterparts were 'absence of prolonged hunger' (P = 0.048) and 'good human-animal relationship' (P = 0.002). Application of the Welfare Quality protocol has raised several concerns about the validity, reliability, and discriminatory potential of the protocol. The results also call for more research into the effect of animal welfare

  8. Epidemiology of Campylobacter spp. at two Dutch broiler farms.

    PubMed Central

    Jacobs-Reitsma, W. F.; van de Giessen, A. W.; Bolder, N. M.; Mulder, R. W.

    1995-01-01

    Broiler flocks on two Dutch poultry farms were screened weekly for the presence of campylobacter in fresh caecal droppings during eight consecutive production cycles. Hatchery and fresh litter samples were taken at the start of each new cycle. Water, feed, insects, and faeces of domestic animals, present on the farms were also included in the sampling. Penner serotyping of isolates was used to identify epidemiological factors that contribute to campylobacter colonization in the broiler flocks. Generally, broiler flocks became colonized with campylobacter at about 3-4 weeks of age with isolation percentages of 100%, and stayed colonized up to slaughter. A similar pattern of serotypes was found within the various broiler houses on one farm during one production cycle. New flocks generally showed also a new pattern of serotypes. Most serotypes isolated from the laying hens, pigs, sheep and cattle were different from those isolated from the broilers at the same time. Campylobacter serotypes from darkling beetles inside the broiler houses were identical to the ones isolated from the broilers. No campylobacter was isolated from any of the hatchery, water, feed or fresh litter samples. Conclusive evidence of transmission routes was not found, but results certainly point towards horizontal transmission from the environment. Horizontal transmission from one broiler flock to the next one via a persistent contamination within the broiler house, as well as vertical transmission from breeder flocks via the hatchery to progeny, did not seem to be very likely. PMID:7781729

  9. Effect of broiler breeder feeding programme and feeder space change at photostimulation using maize- or wheat-based diets on broiler progeny growth performance and leg health.

    PubMed

    Eusebio-Balcazar, P; Oviedo-Rondón, E O; Wineland, M J; Osborne, J; Brake, J

    2015-01-01

    1. The aim of this study was to evaluate the effects of diet type, maternal feeding programme at 29 weeks of age and breeder feeder space change at photostimulation on broiler progeny performance and leg health at 6 weeks of age. 2. Fast-feathering Cobb 500 broiler breeders were fed on either maize- or wheat-based diets that had been formulated to have similar nutrient composition during growing and layer phases. Two feeding programmes, fast or flow, were used from 14 to 29 weeks of age. At 22 weeks, 69 females from each pen were placed in a layer house where feeder space was either similar to that in rearing (6.3 to 6.5 cm/female) or was increased from 6.3 to 8.4 cm/female. Eggs produced at 32 and 44 weeks of age were collected and incubated for two broiler experiments. A total of 16 male and 16 female one-d-old chicks were placed in floor pens in two experiments, respectively, with 6 and 4 replicate pens. Broiler gait scores and leg problem prevalence were evaluated at 6 weeks of age. 3. Data were analysed as a 2 × 2 × 2 factorial design with diet type, feeding programme and feeder space change as main factors. 4. The wheat diet increased the probability of observing crooked toes in broiler progeny compared to the use of maize, but only when breeders were fed according to the fast feeding programme and given similar feeder space as during rearing. 5. Breeders given more feeder space in the laying period produced progeny with more locomotion problems compared with those provided similar feeder space, but only when maize was used and the slow feeding programme was applied to the breeders. 6. The maternal feeding programme interacted with other factors to influence progeny leg health, but it did not solely influence walking ability or leg problems of progeny. 7. In conclusion, an increased probability of observing walking impairment of broiler progeny was detected when breeders were given greater feeder space at photostimulation rather than no change and fed

  10. Effect of electrostatic space charge on reduction of airborne transmission of Salmonella and other bacteria in broiler breeders in production and their progeny.

    PubMed

    Richardson, L J; Hofacre, C L; Mitchell, B W; Wilson, J L

    2003-01-01

    Salmonella in birds is a concern because of the human foodborne illness associated with the consumption of poultry meat and eggs. One of the methods of transmission of Salmonella within a flock can be by the air. Therefore, we used reduction of transmission of Salmonella to monitor the effectiveness of the electrostatic space charge system (ESCS). During the average broiler breeder laying cycle of 40 wk, a large amount of dust becomes airborne and accumulates on walls, ceiling, and equipment. Many microorganisms adhere to these dust particles, making dust an excellent vector for horizontal disease transmission between birds. We used two environmentally controlled rooms containing commercial broiler breeders to evaluate the effectiveness of an ESCS that produced a strong negative electrostatic charge to reduce airborne dust and, subsequently, microorganism levels. The ESCS caused the dust to become negatively charged, therefore moving to the grounded floor in the treatment room. The use of the ESCS resulted in a significant reduction (P < 0.0001, 61% reduction) in airborne dust concentration levels, which resulted in a significant reduction (P < 0.0001, 76% reduction) in total airborne bacteria and gram-negative bacteria (48% reduction) in the treatment room. Significant reductions (P < 0.05) of gram-negative bacteria (63% reduction) on the egg collection belts were also recorded in the treatment room, which resulted in a significant reduction (P < 0.0001) of gram-negative bacteria (28% reduction) on the eggshell surface. The ESCS treatment resulted in fewer Salmonella enteritidis-positive hens and their progeny from the treatment room due to reductions of dust and airborne bacteria. In addition, this significant reduction in bacteria on the eggshell surface should result in less bacteria in the day-old chicks, therefore better early chick livability. There was no significant difference (P > 0.05) in egg production, male or female body weights, mortality, or

  11. Comparative study of the effects of organic selenium on hen performance and productivity of broiler breeders.

    PubMed

    Rajashree, K; Muthukumar, T; Karthikeyan, N

    2014-01-01

    1. A 10-week experiment was conducted with Ross 308 broiler breeder chickens in cages to evaluate the influence of organic and inorganic sources of selenium (Se) supplementation. A total of 600 birds at 29 weeks of age were divided at random into 4 groups and fed on a maize-soya basal diet supplemented with different forms of Se. 2. The first (control) group was given the basal diet without Se supplementation, whereas the second, third and fourth groups were given, respectively, the basal diet with 0.3 mg/kg of inorganic Se in the form of sodium selenite or 0.3 and 0.5 mg/kg of organic Se in the form of Se enriched yeast (Se-yeast). 3. The experiment was carried out for 10 weeks to compare and evaluate the influence of Se supplementation on breeder performance, egg production, hatchability and the quality of eggs. Samples were collected for analysis at weeks 0, 5 and 10 of the experimental period. 4. At the end of the experiment (39 weeks), there was a reduction in mortality in breeders given diets supplemented with 0.5 mg/kg of Se-yeast. Supplementation of feed with 0.5 mg/kg organic Se increased egg production, percentage of settable eggs and hatchability. 5. Selenium supplementation increased egg weight and specific gravity compared to the control diet. However, no significant variation was found in albumen or yolk protein content at the end of week 10. 6. Selenium accumulation and glutathione peroxidase (GSHPx) activity were lower in the egg albumen and yolk of control compared with Se-supplemented treatments. Se accumulation and GSHPx activity were higher in the group given 0.3 mg/kg organic compared to 0.3 mg/kg of inorganic Se. 7. The results favour the use of Se-yeast at the dose of 0.5 mg/kg in broiler breeder diets for better productivity of eggs, settable eggs, hatchability and higher Se accumulation and antioxidant status in eggs. PMID:24814053

  12. The effect of feeding time on shell quality and oviposition time in broiler breeders.

    PubMed

    Backhouse, D; Gous, R M

    2005-04-01

    Three experiments were performed to determine the effect of feeding time on shell quality and oviposition time in broiler breeders. Mean eggshell thickness was increased significantly by 3.5 microm (approximately 1%) per h delay in feeding time when hens were housed in individual cages. However, eggshell thickness was not significantly affected by feeding time when birds were housed on litter floors. Mean oviposition time was delayed relative to lights on by 5 min per h delay in feeding time. Egg weight was not significantly affected by feeding time, suggesting that differences in shell thickness and oviposition times were not due to increased oviducal transit times. Producers who wish to implement delayed feeding may have to turn lights on earlier than usual to compensate for delayed oviposition times.

  13. Higher rates of internal ovulations occur in broiler breeder hens treated with testosterone.

    PubMed

    Navara, Kristen J; Pinson, Sara E; Chary, Parag; Taube, Patrick C

    2015-06-01

    Maximal profit in both the commercial egg and meat industries requires that the quantity of oviposited eggs closely matches the quantity of large yellow follicles maturing in the ovary. While laying hens are genetically selected for maximal egg production and strategies for management of broiler breeders have been constructed to achieve a similar outcome, a percentage of ovarian follicles that are selected into the ovulatory hierarchy in these hens still never make it to oviposition possibly due to atresia of large yellow follicles or internal ovulation of the oocyte into the peritoneal cavity rather than the oviduct. The causes and mechanisms responsible for these processes remain unclear, however, evidence in wild birds suggests that stressful and/or territorial challenges may stimulate oocyte losses. Since testosterone and corticosterone are central to the responses to territorial intrusions and stress, respectively, and since both large yellow follicles and the oviduct that will engulf them are sensitive to hormonal cues, one or both hormones may play a role in the loss of large yellow follicles via atresia and/or internal ovulation in laying hens. To test this, broiler breeder hens were treated with corticosterone or testosterone 5 h prior to ovulation and observed to see whether these treatments influenced the likelihood that a hen would lay an egg 24 h after the predicted ovulation time. A subset of hens that did not lay an egg were killed and dissected to look for evidence of follicle atresia and internal ovulation. Testosterone treatment resulted in significantly more oocyte losses, and 60% of these occurred due to internal ovulations, as was indicated by the presence of yolk in the peritoneal cavity. Corticosterone did not influence the rate of oocyte losses, follicle atresia, or internal ovulation. These results suggest that testosterone can cause disruptions that ultimately prevent the oviduct from capturing the oocyte after ovulation.

  14. Effects of incubator humidity and hen age on yolk composition in broiler hatching eggs from young breeders.

    PubMed

    Burnham, M R; Peebles, E D; Gardner, C W; Brake, J; Bruzual, J J; Gerard, P D

    2001-10-01

    The effects of broiler breeder age (26, 28, and 30 wk) and incubator relative humidity (43, 53, and 63% RH) on yolk sac weight and composition in broiler hatching eggs between 16 and 19 d of incubation were evaluated. Percentage yolk sac weight was reduced in eggs from the youngest (26 wk) breeder hens and in eggs incubated at 53% RH. Percentage yolk moisture, in eggs from the youngest hens, was lowest at 16 d and was highest at 19 d, and percentage yolk lipid was highest at 16 and 17 d of incubation in eggs from 30-wk-old hens. Percentage yolk lipid content was higher at 63% RH compared with 53% RH in eggs from 26-wk-old breeders but was lower in eggs incubated at a 43% RH compared with 53 and 63% RH from 30-wk-old breeders. Yolk stearic and arachidonic acid concentrations were higher and myristic acid concentration was lower in eggs from the 26-wk-old hens. Conversely, the highest yolk concentrations of linolenic and palmitoleic acids occurred in eggs from 30- and 28-wk-old breeders, respectively. At 16, 17, 18, and 19 d of incubation, yolk oleic acid concentrations were significantly, but variably, affected by breeder age, whereas linoleic acid concentration was highest in 26-wk-old breeders only at 19 d. Palmitic acid concentration at 17 d was lower in eggs incubated at 53% RH compared with 43 and 63% RH. Rate of yolk uptake from the yolk sac by embryos may be increased by incubating eggs at 53% RH, and the effects of changes in RH between 43 and 63% on yolk lipid content are influenced by breeder age.

  15. Jojoba meal (Simmondsia chinensis) in the diet of broiler breeder pullets: physiological and endocrinological effects.

    PubMed

    Arnouts, S; Buyse, J; Cokelaere, M M; Decuypere, E

    1993-09-01

    The present studies evaluated the ability of jojoba meal (JO) to inhibit feed intake of broiler breeder pullets to limit body weight gain as recommended by the breeder company. A first experiment, using graded levels of JO supplementation (0 to 12%), was conducted to establish appropriate JO supplementation. Adequate reduction of growth rate was obtained with 4% JO supplementation. However, notwithstanding their similar growth rate, 4% JO chickens consumed considerably more feed compared with feed-restricted chickens. The dose-dependent impairment of feed intake with increasing levels of JO supplementation was also associated with increased plasma growth hormone and thyroxine and with decreased plasma insulin-like growth factor-I and triiodothyronine concentrations compared with 0% JO chickens. A second experiment included a pair-fed group. Notwithstanding their similar feed intake, 4% JO chickens gained significantly less body weight compared with their pair-fed counterparts. The 4% JO chickens also had a longer feed transit time per kilogram body weight. Again, circulating levels of the somatotrophic and thyrotrophic hormones were altered according to the dietary treatment. From all these observations, it was concluded that the growth retardation caused by JO supplementation was provoked by an inhibition of appetite linked with the simmondsin content of JO as well as by other antinutritional compounds affecting digestibility.

  16. Isolation, identification, and pathogenicity of O142 avian pathogenic Escherichia coli causing black proventriculus and septicemia in broiler breeders.

    PubMed

    Wang, Xiaobo; Cao, Chunguang; Huan, Haixia; Zhang, Liuli; Mu, Xiaohui; Gao, Qingqing; Dong, Xianglei; Gao, Song; Liu, Xiufan

    2015-06-01

    Avian colibacillosis, characterized by black proventriculus and caused by avian pathogenic Escherichia coli (APEC) with an uncommon O142 serogroup, was diagnosed in young broiler breeders. Colonization and persistence assays performed in 7-day-old broilers showed that the bacterial load of the APEC 4d/9-1 O142 proventricular isolate in the lung was about 10-fold higher than that of the APEC 4d/9-1 O142 heart blood isolate (P<0.01), and about 100-fold higher in the heart blood, livers, spleens, kidneys, and proventriculi of inoculated broilers (P<0.001). When 32 common virulence genes of APEC were tested, the two isolates had nearly identical profiles, except that only the APEC 4d/9-1 O142 proventricular isolate carried the feoB gene. Furthermore, 100% mortality was observed in both 1-day-old Arbor Acres (AA) broilers and 1-day-old specific-pathogen-free (SPF) chickens inoculated with 10(6) colony-forming units of the APEC 4d/9-1 O142 proventricular isolate. However, black proventriculus was only observed in the dead AA broilers, consistent with the clinical occurrence of the disease. This implies that the black proventriculi seen in the dead birds, caused by the APEC 4d/9-1 O142 proventricular isolate, was breed-specific. Both the APEC 4d/9-1 O142 proventricular and heart blood isolates belong to phylogroup B2. However, the former was assigned to ST131 and the latter to ST2704 with multilocus sequence typing, demonstrating the genetic heterogeneity of these two bacterial isolates, although they were derived from the same dead broiler. These results suggest that the O142 APEC isolate was the main pathogenic agent for black proventriculi in 7-day-old broiler breeders.

  17. Effects of feeder space allocations during rearing, female strain, and feed increase rate from photostimulation to peak egg production on broiler breeder female performance.

    PubMed

    Leksrisompong, N; Romero-Sanchez, H; Oviedo-Rondón, E O; Brake, J

    2014-05-01

    A study was conducted to determine if there were differences in female broiler breeder performance of 2 strains that had been subjected to 2 feeder space allocations during the growing period followed by 2 feeding to peak programs. Ross 308 and 708 pullets were reared with a single feeding program to 23 wk of age and with 2 circumferential feeder space allocations (5.3 cm/female or 7.0 cm/female) and then assigned to 2 feed increase programs (slow or fast) from photostimulation to peak egg production. The flock was moved to the laying house with 8.8 cm/female of female feeder space and photostimulated at 23 wk of age when Ross 344 males were added to create 16 pens with 60 females and 7 males each in a 2 × 2 × 2 design. The fast feed increase program significantly increased female BW at 31 wk of age, which could have contributed to an increased female mortality during the summer weather of early lay. The 708 females with 5.3 cm/female feeder space produced smaller eggs at 28 and 30 wk of age. The 708 females exhibited better fertile hatchability than 308 females due to fewer late dead embryos. There were no differences in egg production, fertility, or fertile hatchability due to the main effects of feeding to peak program or growing feeder space, but the slow feed increase from photostimulation to peak production reduced cumulative mortality.

  18. Choice of nest types by hens of three lines of broiler breeders.

    PubMed

    Holcman, A; Malovrh, S; Stuhec, I

    2007-06-01

    1. Choice of three different nest types by hens of broiler breeder lines was investigated: metal nests (26 x 29 x 33-45 cm, w x d x h) with inclined rubber mats, metal nests of the same size with litter, and larger wooden nests (30 x 40 x 38) with litter. Three lines were studied: line B (324 females + 36 males), line P (315 + 36), and line WM (306 + 32). Each line was housed in a pen 23.3 x 3.9 m (90.7 m2); half the area was concrete floor with litter, and the other half raised plastic slats, on which stood 84 nests, 28 of each type, in two-tier blocks. 2. Ninety-five per cent of eggs were laid in nests, with significant variation between types: 63% metal littered, 30% wooden littered, and 2.3% metal with inclined rubber mats. Choice between types was similar in the three lines. Hens of line B laid 66% of nest eggs in lower nests, P laid 57% and WM laid 64%. 3. The other 5.1% of eggs were laid on the floor: 1.2% on the litter and 3.9% on the slats in front of the nests. It is suggested that some subordinate hens were excluded from nests, and therefore laid on the floor. PMID:17578690

  19. Effects of dietary L-arginine on laying performance and antioxidant capacity of broiler breeder hens, eggs, and offspring during the late laying period.

    PubMed

    Duan, Xiaoxue; Li, Feng; Mou, Shaoyang; Feng, Jiawei; Liu, Peifeng; Xu, Liangmei

    2015-12-01

    The effects of maternal L-arginine supplementation on laying performance and the antioxidant capacity of broiler breeder hens, egg yolk, and their one-day-old offspring were investigated. In a 9 wk experiment, 210 60-week-old Arbor Acres healthy female broiler breeders were randomly divided into 5 treatments with 6 replicates of 7 females and fed a corn and soybean meal diet with 5 arginine levels (0.96%, 1.16%, 1.36%, 1.56%, and 1.76% digestible arginine). Laying performance and anti-oxidant capacity of broiler breeder hens, eggs, and offspring were evaluated. Digestible arginine level in the broiler breeder diet had a significant effect on the laying rate (linear and quadratic effect, P<0.0001). The highest laying rate was obtained when the diet with 1.36% digestible arginine was fed. There was a significant effect of digestible arginine level in the broiler breeder diet on the total antioxidant capacity (T-AOC) levels and methane dicarboxylic aldehyde (MDA) concentration in the broiler breeder serum, egg yolk and serum, and liver and breast of one-day-old offspring (linear and quadratic effect, P<0.05). The T-AOC level was highest and the MDA concentration lowest in all tissues when a diet with 1.36% digestible arginine was fed. No difference in glutathione peroxidase (GSH-PX) activity in the broiler breeder serum was observed. There were significant effects of digestible arginine level in the broiler breeder diet on the GSH-PX activity of the egg yolk (linear effect, P<0.01; quadratic effect, P<0.05) and serum, liver, and breast of one-day-old offspring (linear and quadratic effect, P≤0.01). The GSH-PX activity in all tissues measured in this experiment was highest when the dietary digestible arginine was 1.36%. These results indicate that the diet with 1.36% digestible arginine (1,972 mg/d) is optimal to satisfy the nutritional needs of a female broiler breeder during the late laying period.

  20. Campylobacter jejuni in broilers: the role of vertical transmission.

    PubMed Central

    Shanker, S.; Lee, A.; Sorrell, T. C.

    1986-01-01

    The role of broiler eggs in the transmission of Campylobacter jejuni to broiler grow-out flocks was investigated. Six breeder flocks supplying broiler eggs to hatcheries were examined for cloacal carriage of C. jejuni. Of 240 birds tested, 178 (74%) were C. jejuni-positive. Eggs from these birds examined for C. jejuni penetration of the egg shell indicated that 185 of 187 were campylobacter-free. Eggs from breeder flocks of unknown C. jejuni status were also examined for C. jejuni shell penetration. C. jejuni was not isolated from 142 eggs examined. A further 193 hatchery eggs incubated and hatched in the laboratory were campylobacter-free. Six farms containing the progeny of C. jejuni-positive breeder flocks were monitored. Eight hundred and forty birds from 14 flocks in these grow-out farms were campylobacter-free during their 6-week grow-out period. Experimental egg-penetration studies indicated that C. jejuni transmission via the egg is not easily effected. Of 257 eggs surface-challenged with C. jejuni, 162 hatched; all were campylobacter-free. Of 167 eggs injected with C. jejuni, 12 hatched; 2 of these were colonized with C. jejuni. Our data do not support a role for vertical transmission of C. jejuni in commercial broiler production. PMID:3701037

  1. Temperature-related risk factors associated with the colonization of broiler-chicken flocks with Campylobacter spp. in Iceland, 2001-2004

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Our objective was to identify temperature-related risk factors associated with the colonization of broiler-chicken flocks with Campylobacter spp. in Iceland, with an underlying assumption that at minimum ambient temperatures, flies (Musca domestica) play a role in the epidemiology and seasonality of...

  2. Lysine partitioning in broiler breeders is not affected by energy or protein intake when fed at current industry levels.

    PubMed

    Ekmay, R D; Salas, C; England, J; Cerrate, S; Coon, C N

    2014-07-01

    A study was conducted to determine the effects of dietary energy and protein intake on the partitioning of lysine in broiler breeder hens. One hundred twenty-six broiler breeders were randomly assigned to 1 of 6 dietary treatments in a 2 (390, 450 kcal/d) × 3 (22, 24, 26 g of CP/d) fashion. Thirty-six hens were administered a daily oral dose of 15 mg of (15)N-Lys for a period of 2 wk or until first egg. After the 2-wk enrichment period, no isotopes were given for 2 d. After 2 d, a daily oral dose of 15 mg of (2)D4-Lys was administered until the 2nd, 3rd, and 4th egg (saved) after the initial (2)D4-Lys was given, at which point pectoralis muscle was sampled. Weeks 25, 29, and 45 were assessed. Isotopic enrichment of pectoralis muscle, egg yolk, and albumen was determined via gas chromatography-mass spectrometry. The (15)N-Lys was intended to represent endogenous lysine, whereas the (2)D4-Lys was intended to represent dietary lysine. Greater than 78% of all labeled lysine ((15)N and (2)D4-Lys) was found in breast muscle. Endogenous muscle was the main source of lysine for yolk formation at wk 25 and 45. Diet was the main source of lysine for albumen formation at wk 25 and 29. A consistent decrease in the (15)N-Lys in breast muscle from the 2nd to the 3rd egg was observed, while also seeing an increase in the (15)N-Lys in the egg from the 3rd to the 4th egg. No difference in the partitioning of lysine was determined by energy or protein intake at levels typical for the current poultry industry. Rather, age, and possibly rate of production, appear to be the main drivers of lysine partitioning in the broiler breeder hen.

  3. Effects of body weight at, and lighting regimen and growth curve to, 20 weeks on laying performance in broiler breeders.

    PubMed

    Gous, R M; Cherry, P

    2004-08-01

    1. A total of 4000 Ross broiler breeders were reared to a 20-week target body weight of 1.55, 2.16 (standard), 2.50 or 2.84 kg, using either a convex or concave growth curve. Each treatment group was either exposed to a conventional broiler breeder lighting regimen, with a series of weekly one-hour increments in photoperiod from 8h at 19 weeks to a 16-h maximum, or maintained from 4d on a 17-h photoperiod. 2. Each 100 g increment in body weight at 20 weeks was associated with a significant increase of 0.55 kg in cumulative food intake, and a 1.5-d advance in sexual maturity. However, leaner body weights at 20 weeks resulted in smaller body weight gains between 20 and 60 weeks (-2.4 g/d/kg body weight at 20 weeks), and an increased production of double-yolked eggs. Neither egg production nor mean egg weight was affected by 20-week body weight. 3. Birds fed to produce more rapid early growth had higher feed intakes to 20 weeks, but reached sexual maturity 7 d later than birds permitted accelerated growth from 15 weeks. Growth curve did not influence body weight gain in lay, egg production or mean egg weight. 4. Birds maintained on 17-h photoperiods reached sexual maturity 27 d later, produced 7 fewer eggs to 60 weeks, and had a mean egg weight 1.2 g heavier than birds photostimulated at 19 weeks. Lighting treatment did not affect food intake to 20 weeks, the proportion of double-yolked eggs or body weight gain between 20 and 60 weeks. 5. Birds fed to have a faster growth early in the rearing phase and maintained on 17-h photoperiods produced 11 fewer eggs than those fed to have accelerated growth at the end of the rearing phase, yet there was only one egg difference between the growth-curve groups for the conventionally lighted birds, which was not significant. 6. The earlier sexual maturity of the conventionally lighted birds compared with those maintained on 17-h photoperiods either indicates that broiler breeders require an increment in photoperiod to stimulate

  4. Genetic Diversity of Campylobacter jejuni and Campylobacter coli Isolates from Conventional Broiler Flocks and the Impacts of Sampling Strategy and Laboratory Method

    PubMed Central

    Colles, F. M.; Rodgers, J. D.; McCarthy, N. D.; Davies, R. H.; Maiden, M. C. J.; Clifton-Hadley, F. A.

    2016-01-01

    The genetic diversity of Campylobacter jejuni and Campylobacter coli isolates from commercial broiler farms was examined by multilocus sequence typing (MLST), with an assessment of the impact of the sample type and laboratory method on the genotypes of Campylobacter isolated. A total of 645 C. jejuni and 106 C. coli isolates were obtained from 32 flocks and 17 farms, with 47 sequence types (STs) identified. The Campylobacter jejuni isolates obtained by different sampling approaches and laboratory methods were very similar, with the same STs identified at similar frequencies, and had no major effect on the genetic profile of Campylobacter population in broiler flocks at the farm level. For C. coli, the results were more equivocal. While some STs were widely distributed within and among farms and flocks, analysis of molecular variance (AMOVA) revealed a high degree of genetic diversity among farms for C. jejuni, where farm effects accounted for 70.5% of variance, and among flocks from the same farm (9.9% of variance for C. jejuni and 64.1% for C. coli). These results show the complexity of the population structure of Campylobacter in broiler production and that commercial broiler farms provide an ecological niche for a wide diversity of genotypes. The genetic diversity of C. jejuni isolates among broiler farms should be taken into account when designing studies to understand Campylobacter populations in broiler production and the impact of interventions. We provide evidence that supports synthesis of studies on C. jejuni populations even when laboratory and sampling methods are not identical. PMID:26873321

  5. Use of neural network models to estimate early egg production in broiler breeder hens through dietary nutrient intake.

    PubMed

    Faridi, A; Golian, A

    2011-12-01

    In this study, neural network (NN) models were constructed to predict early egg production in broiler breeder hens. By breaking down the early egg production data collected from 98 breeder houses into weekly intervals, 5 NN-based models were developed for 25 to 29 wk of age. Starting with 98 data lines for each week, the NN models were trained by 69 data lines and the remainder (n = 29) were considered as the testing set. The variables of interest for developing the models were ME (kcal/bird per day) and CP, TSAA, Lys, Ca, and available P (g/bird per day). The constructed models were subjected to an optimization algorithm. Therefore, the optimal values for the input variables to maximize early egg production in broiler breeder hens were obtained. Based on the considered criteria to evaluate the goodness of fit, the efficiency of NN-based models to estimate early egg production was confirmed. The optimization results revealed that the breeder hens consuming 407, 457, 470, 486, and 487 kcal of ME/bird per day showed the highest egg production during 25, 26, 27, 28, and 29 wk of age, respectively. Moreover, optimal performance of hens required the intake (g/bird per day) of the following during 25, 26, 27, 28, and 29 wk of age, respectively: CP: 20.3, 22.6, 25, 25.8, and 26; TSAA: 0.88, 1.02, 1.06, 1.07, and 1.07; Lys: 0.98, 1.0, 1.2, 1.3, and 1.32; Ca: 4.5, 4.6, 5.3, 5.0, and 5.4; and available P: 0.48, 0.55, 0.6, 0.61, and 0.62. Although the results showed that the energy and other nutrient requirements of broiler breeder hens during early egg production do not change in parallel with age, it seems that the company recommendations underestimated the nutrient requirements of hens during these weeks.

  6. Darkling Beetles as a Potential Transmission Source of Salmonella in Broiler Flocks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The adult and larval darkling beetles (Alphitobius diaperinus Panzer) are common insect pests of commercial broiler operations. High populations of darkling beetles in commercial broiler operations can have a negative impact finanacially due to structural and insulation damage within the house, red...

  7. Comparison of different sampling types across the rearing period in broiler flocks for isolation of Campylobacter spp.

    PubMed

    Ingresa-Capaccioni, S; González-Bodí, S; Jiménez-Trigos, E; Marco-Jiménez, F; Catalá, P; Vega, S; Marin, C

    2015-04-01

    Campylobacter is the most common bacterial cause of human gastrointestinal disease in most developed countries. It is generally accepted that poultry products are a significant source of foodborne Campylobacter infections in humans. Assessing the effectiveness of any potential intervention at farm level requires monitoring of the Campylobacter status of broiler flocks, using appropriate sampling methods. The aim of this study was to assess the influence of the sample type across the rearing period for the detection of Campylobacter spp. at farm level. During this study, 21 commercial broiler farms were intensively sampled. Each farm was visited and sampled at different times during the rearing period (d 1, 7, 14, 21, 28, 35, and 42). On the first day of rearing, the status of the house and the day-old flock was evaluated, and environmental and cecal samples were collected. During rearing, 4 different sample types were collected: feces with sock swabs (sock swabs), feces directly from the litter (feces), cloacal swabs, and cecal content. All samples were analyzed according to ISO 10272-1:2006 (Annex E) and also by direct culture. The results of this study showed that Campylobacter spp. were detected in all of the sample types on d 14 of rearing. From this point on, the detection increased significantly, with a maximum detection rate by the end of rearing, regardless of the sample type. All samples that were negative upon direct culture were also negative after pre-enrichment. At the end of rearing, the percentage of samples positive for Campylobacter spp. was 71.4% for cecal samples, 61.9% for cloacal swabs, 45.2% for sock swabs, and 69.1% for fecal samples. C. jejuni was detected in all the sample types, with positive rates ranging from 67.1 to 76.0% for cecal samples and cloacal content, respectively. Cecal samples, cloacal swabs, and fecal samples cultured by direct plating onto modified charcoal cefoperazone deoxycholate agar (mCCDA) without pre-enrichment have

  8. Comparison of different sampling types across the rearing period in broiler flocks for isolation of Campylobacter spp.

    PubMed

    Ingresa-Capaccioni, S; González-Bodí, S; Jiménez-Trigos, E; Marco-Jiménez, F; Catalá, P; Vega, S; Marin, C

    2015-04-01

    Campylobacter is the most common bacterial cause of human gastrointestinal disease in most developed countries. It is generally accepted that poultry products are a significant source of foodborne Campylobacter infections in humans. Assessing the effectiveness of any potential intervention at farm level requires monitoring of the Campylobacter status of broiler flocks, using appropriate sampling methods. The aim of this study was to assess the influence of the sample type across the rearing period for the detection of Campylobacter spp. at farm level. During this study, 21 commercial broiler farms were intensively sampled. Each farm was visited and sampled at different times during the rearing period (d 1, 7, 14, 21, 28, 35, and 42). On the first day of rearing, the status of the house and the day-old flock was evaluated, and environmental and cecal samples were collected. During rearing, 4 different sample types were collected: feces with sock swabs (sock swabs), feces directly from the litter (feces), cloacal swabs, and cecal content. All samples were analyzed according to ISO 10272-1:2006 (Annex E) and also by direct culture. The results of this study showed that Campylobacter spp. were detected in all of the sample types on d 14 of rearing. From this point on, the detection increased significantly, with a maximum detection rate by the end of rearing, regardless of the sample type. All samples that were negative upon direct culture were also negative after pre-enrichment. At the end of rearing, the percentage of samples positive for Campylobacter spp. was 71.4% for cecal samples, 61.9% for cloacal swabs, 45.2% for sock swabs, and 69.1% for fecal samples. C. jejuni was detected in all the sample types, with positive rates ranging from 67.1 to 76.0% for cecal samples and cloacal content, respectively. Cecal samples, cloacal swabs, and fecal samples cultured by direct plating onto modified charcoal cefoperazone deoxycholate agar (mCCDA) without pre-enrichment have

  9. Effects of growth patterns and dietary protein levels during rearing of broiler breeders on fertility, hatchability, embryonic mortality, and offspring performance.

    PubMed

    van Emous, R A; Kwakkel, R P; van Krimpen, M M; van den Brand, H; Hendriks, W H

    2015-04-01

    The objective of this study was to determine the effects of different growth patterns and dietary crude protein levels during rearing in broiler breeder females on fertility, hatchability, embryonic mortality, and offspring performance. A 2×3 factorial arrangement of treatments was used, with 2 growth patterns to reach a target body weight at 20 wk of age of 2,200 g (standard=standard growth pattern) or 2,400 g (high=high growth pattern), and 3 dietary protein levels (high=crude protein, high), (medium=crude protein, medium), and low=crude protein, low). Fresh egg composition and organ development in hatchlings were determined. Offspring of the different groups were reared until an age of 34 d and feed intake, body weight gain, mortality, and carcass composition were determined. In 29-wk-old high growth pattern breeders compared to standard growth pattern breeders, fertility and hatchability of set eggs were increased; embryonic mortality between d 1 and 9 was decreased whereas hatchability of fertile eggs was not affected. Breeders fed the medium crude protein diet showed a decreased hatchability of fertile eggs caused by an increased embryonic mortality between d 18 and 21 compared to breeders fed the high crude protein and low crude protein diets. Offspring of 29-wk-old high growth pattern breeders tended (P=0.059) to have a higher body weight at d 34 than offspring of standard growth pattern breeders, which was achieved by a tendency to a higher body weight gain (P=0.057). Offspring of breeders fed the medium and low crude protein diet showed a higher feed intake between d 18 and 27 and during the total growth period, as compared to offspring of high crude protein breeders. Male broilers of low crude protein breeders had higher breast meat yield than male broilers of high crude protein breeders, while breast meat yield of female broilers was not affected by dietary protein levels. This experiment showed that a higher growth pattern during the rearing period

  10. Effects of maternal dietary EPA and DHA supplementation and breeder age on embryonic and post-hatch performance of broiler offspring: age and n-3 pufa affect embryonic and post-hatch performance.

    PubMed

    Koppenol, A; Delezie, E; Wang, Y; Franssens, L; Willems, E; Ampe, B; Buyse, J; Everaert, N

    2015-04-01

    Breeder age and nutrition are amongst the most important factors affecting progeny growth and development. The present experiment was carried out to evaluate the effects of n-3 fatty acid (FA), with special emphasis on the ratio of eicosapentaenoic (EPA, 20:5 n-3) and docosahexaenoic (DHA, 22:6 n-3) acid, provided to the diet of ageing broiler breeder hens at different ratios, on the incubation parameters and the performance of the offspring. Four hundred and eighty Ross-308 broiler breeder hens were fed one of four different diets (120/treatment), with an equal fat content. The control diet was a basal diet, rich in n-6 FAs (CON). Blends of fish oil were used to enrich the three other diets in n-3 FA and to obtain different EPA/DHA ratios of 1/1 (EPA=DHA), 1/2 (DHA) or 2/1 (EPA). Every 5 weeks, incubation parameters were assessed. Every 15 weeks, offspring was reared until slaughter age on a standard diet. Breeder age affected almost all incubation and post-hatch parameters, whereas n-3 FA treatment only lowered egg weight (p < 0.0001) and consequently hatched chick weight (p < 0.0001). Supplementation of EPA resulted in a higher proportional liver weight (p = 0.0219) at hatch, a lower body weight up to 28 days post-hatch (p = 0.0418), a lower daily weight gain (p = 0.0498) and a higher feed conversion ratio (p = 0.0395) during the starter period (p = 0.0498), resulting in a higher overall offspring feed conversion ratio (p = 0.0317) compared to the control diet. DHA supplementation, on the other hand, resulted in a lower residual yolk weight (p = 0.0220) and a higher overall offspring mortality (p = 0.0125). In conclusion, supplementation of n-3 FA could not counter the adverse effect of breeder flock age, but did not harm incubation or improve post-hatch performance, either. EPA and DHA affected offspring development differently during early post-hatch life.

  11. The effect of dietary alterations during rearing on feather condition in broiler breeder females.

    PubMed

    Morrissey, K L H; Widowski, T; Leeson, S; Sandilands, V; Arnone, A; Torrey, S

    2014-07-01

    In commercial production, broiler breeders are severely feed restricted to maintain healthy BW. This restriction can induce stereotypic behavior, including feather pecking, which has negative welfare implications for both the victim and performer. It has been suggested that the problem may be symptomatic of chronic hunger or the frustration of feeding motivation. In this study, we determined whether feather condition, as an indirect measure of feather pecking, could be improved via dietary manipulation. Six dietary treatments were tested, each with 5 replicate pens of 9 to 12 birds. Control diets (C) were fed on a daily or skip-a-day (SAD) basis. Alternative diets included soybean hulls as a bulking ingredient and calcium propionate (CaP) as an appetite suppressant of either a feed grade (F) or purified (P) quality. Both alternative diets were fed on either a daily or SAD basis. Five or 6 birds were randomly chosen from each pen and feather scored at 10, 14, 20, 26, and 36 wk of age. Six body parts (neck, back, wings, legs, vent area, tail) were given a score from 0 to 5 (0 = no feather damage, and 5 ≥ 50% feather loss with tissue damage). Scores were summed for each bird and averaged for each pen. Data were analyzed with room and feeding frequency as main factors and diet as the subfactor with repeated measures. There was an interaction between diet and time (P < 0.01) with the feather condition of the C birds worsening more quickly in comparison with the F and P birds. There was an interaction between feeding frequency and time (P = 0.015), with SAD-fed birds scoring better than daily-fed birds at 20, 26, and 36 wk. This interaction could indicate that SAD feeding increased satiety after the birds became accustomed to the schedule. Because feather condition was better with the alternative diets, this may indicate a reduction in stereotyped feather pecking with these diets. This suggests that the alternative diets increase satiety compared with the control diets.

  12. Impact of Skip a Day and Every Day Feeding Programs on the Colonization Rates of Salmonella Enteritidis in Broiler Breeder Pullets

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The impact of feeding programs in the colonization rate after challenge with Salmonella enteritidis was investigated. Broiler breeder pullets from were vaccinated at 19 d of incubation with herpesvirus of turkeys (HVT) + chicken herpesvirus (SB1), or a vector HVT (vHVT) + Infectious bursal disease (...

  13. Effect of feeding guanidinoacetic acid and L-arginine on the fertility rate and sperm penetration in the perivitelline layer of aged broiler breeder hens.

    PubMed

    Sharideh, H; Esmaeile Neia, L; Zaghari, M; Zhandi, M; Akhlaghi, A; Lotfi, L

    2016-04-01

    Two experiments were conducted to evaluate the effects of feeding guanidinoacetic acid (GAA) and L-arginine (ARG) on fertility and sperm penetration (SP) rate of broiler breeder hens. In the first experiment, a total of 200 broiler breeder hens (Ross 308) aged 53 weeks were randomly allotted to four dietary treatments (0, 0.6, 1.2 and 1.8 g GAA/kg diet) with five replicates of 10 birds each. In the second experiment, 320 broiler breeder hens (Ross 308) were used from 53 to 62 weeks of age in a 2 × 4 factorial arrangement (0 or 1.2 g GAA/kg diet along with 0, 3, 6 or 9 g ARG/kg diet). The hens received a diet containing 2800 kcal ME/kg and 14% CP. Sixteen sexually mature Ross 308 breeder roosters (34 weeks old) were used to artificially inseminate the hens. Fertility of the hens was determined in 61 and 62 weeks of age. The sperm penetration holes in the inner perivitelline layer (IPL) overlying the germinal disc were enumerated on days 3 and 7 following each insemination. Adding GAA to the breeder diet increased the number of SPs in the IPL and fertility in both experiments (p < 0.01). The interactive effect of ARG and GAA on the SP and fertility was significant. Supplementary ARG increased the SP rate in the IPL (p < 0.01). In conclusion, dietary supplementation of GAA and ARG might be potentially used to improve the fertility of broiler breeder hens at the later phase of the egg production period.

  14. Epidemiological associations between characteristics of registered broiler chicken flocks in Canada and the Salmonella culture status of floor litter and drinking water

    PubMed Central

    Renwick, Shane A.; Irwin, Rebecca J.; Clarke, Robert C.; McNab, W. Bruce; Poppe, Cornelius; McEwen, Scott A.

    1992-01-01

    A Canada-wide flock management survey of 294 randomly selected commercial broiler chicken flocks was conducted during 1989-1990. The prevalence of flocks that yielded Salmonella from cultures of floor litter or drinking water, and the prevalence of floor litter samples that yielded Salmonella, were significantly associated (p < 0.05) with the age of the flock and the region of Canda in which the flock was located. Culture of Salmonella from the drinking water was significantly associated (p < 0.05) with the type of drinker used, the dead bird disposal method, and the region of Canada in which the flock was located. There was a significantly greater risk (p < 0.05) of contamination of drinking water with Salmonella from trough drinkers (odds ratio = 7.99) and plastic bell drinkers (odds ratio = 6.10) than from nipple drinkers. No significant associations were found between pest control, restrictions on visitors, clean-out methods, or water sanitization and the culture of salmonellae from floor litter or drinking water. ImagesFigure 3. PMID:17424037

  15. Risk factors for Campylobacter spp. colonization in French free-range broiler-chicken flocks at the end of the indoor rearing period.

    PubMed

    Huneau-Salaün, A; Denis, M; Balaine, L; Salvat, G

    2007-06-15

    The aim of this cross-sectional survey was to identify risk factors for Campylobacter spp. colonization in French free-range broiler flocks at the end of the indoor rearing period (between 35 and 42 days old). Seventy-three broiler farms were studied from March 2003 to March 2004 in France. A questionnaire was administered to the farmers and samples of fresh droppings were taken to assess the flocks'Campylobacter status by bacteriology. Campylobacter species were determined by PCR. A logistic regression analysis was used to assess the influence of various factors on flocks'Campylobacter status. 71.2% of the sampled flocks excreted Campylobacter spp. before going out on the range. The risk of a flock being colonized with Campylobacter was increased in the spring/summer period (RR=1.8, p=0.02) and autumn (RR=2.2, p=0.02) compared to winter, on total freedom rearing farms (RR=3.3, p=0.04) in comparison with farms with a fenced run, when the first disinfection of the poultry-house was performed by the farmer (RR=2.4, p=0.04) instead of a hygiene specialist, when rodent control was carried out by a contractor (RR=1.8, p<0.01) and not by the farmer and when the farmer came into the house twice a day as opposed to three time a day or more (RR=1.5, p=0.02). Use of a specific gate for chick placement decreased the risk of a flock being colonized with Campylobacter (RR=0.5, p=0.01) in comparison with using the gate for manual disposure or the door of the change room.

  16. The influence of stocking density on body weight, egg weight, and feed intake of adult broiler breeder hens.

    PubMed

    Mtileni, B J; Nephawe, K A; Nesamvuni, A E; Benyi, K

    2007-08-01

    The influence of stocking density on BW, egg weight (EW), and feed intake (FI) in Ross broiler breeder hens (n = 120) was investigated during the late medium egg production period (from 50 to 54 wk of age). Birds were randomly allocated to 6 pens in densities of 15, 20, and 25 birds/pen, giving rise to a floor space allowance of 5, 6.67, and 8.33 birds/m(2), respectively. Each density was replicated twice, and the order among the 6 pens was chosen at random. Data were analyzed using the repeated measures techniques of the Statistical Analysis System, considering the covariance structure of the observed data. There was a significant effect attributable to stocking density, time (in days), and their interaction for BW, EW, and FI. Birds in density of 6.67 per m(2) were lighter but had heavier eggs than birds in density of 5 per m(2); however, birds in density of 8.33 per m(2) had similar BW and EW with birds in the other 2 groups. The mean FI were statistically different among the 3 groups, with a reduction in FI as density increases. Total egg production within the 3 density groups and average egg production per bird were also analyzed using categorical data techniques. The results indicated that stocking density influenced egg production, with birds at higher density producing fewer eggs per bird. Although generous floor space allowances were allocated per bird in this experiment, stocking density influenced the performance of broiler breeder hens.

  17. Efficacy of several vaccination programmes in commercial layer and broiler breeder hens against experimental challenge with Salmonella enterica serovar Enteritidis.

    PubMed

    Penha Filho, Rafael Antonio Casarin; de Paiva, Jacqueline Boldrin; Arguello, Yuli Melisa Sierra; da Silva, Mariana Dias; Gardin, Yannick; Resende, Fernando; Berchieri Junior, Angelo Berchieri; Sesti, Luiz

    2009-10-01

    Two experiments were performed to evaluate the protective effect of various vaccination combinations given at 5 and 9 weeks of age against experimental challenge with Salmonella enterica serovar Enteritidis (SE) phage type 4 at 12 weeks of age. In Experiment 1, groups of commercial layers were vaccinated by one of the following programmes: Group 1, two doses of a SE bacterin (Layermune SE); Group 2, one dose of a live Salmonella enterica serovar Gallinarum vaccine (Cevac SG9R) followed by one dose of the SE bacterin; Group 3, one dose of each of two different multivalent inactivated vaccines containing SE cells (Corymune 4K and Corymune 7K; and Group 4, unvaccinated, challenged controls. In Experiment 2, groups of broiler breeders were vaccinated by the same programmes as Groups 1 and 2 above while Group 3 was an unvaccinated, challenged control group. All vaccination programmes and the challenge induced significant (P < 0.05) seroconversion as measured by enzyme-linked immunosorbent assay. Overall, in both experiments, all vaccination schemes were significantly effective in reducing organ (spleen, liver and caeca) colonization by the challenge strain as well as reducing faecal excretion for at least 3 weeks. Vaccinated layers in Groups 1 and 2 and broiler breeders in Group 2 showed the greatest reduction in organ colonization and the least faecal excretion. In Experiment 1, layers vaccinated with multivalent inactivated vaccines containing a SE component (Group 3) were only moderately protected, indicating that such a vaccination programme may be useful in farms with good husbandry and housing conditions and low environmental infectious pressure by Salmonella.

  18. Comparison of embryo physiological parameters during incubation, chick quality, and growth performance of three lines of broiler breeders differing in genetic composition and growth rate.

    PubMed

    Tona, K; Onagbesan, O M; Jego, Y; Kamers, B; Decuypere, E; Bruggeman, V

    2004-03-01

    In broiler breeder management, stringent feed restriction is practiced to reduce body size in order to improve egg production and meet broiler production demand, but this practice has raised welfare issues. The potential for the dwarfing (dw) gene to reduce feed intake and body size of breeders under ad libitum feeding or less stringent restriction while maintaining improved egg production has been reported. In this study, we compared embryo physiology, quality of chicks, and performance of broilers from eggs of dwarf breeders with those from a standard broiler breeder. Hatching eggs from 3 commercial lines of broiler breeders were compared for incubation parameters, 1-d-old chick weight, chick quality, and broiler growth to 41 d of age. The lines included a standard heavy (S) line, an experimental (E) line, and a label-type (L) line. The E and L line breeders carry the sex-linked dw gene and are being used to assess the potential for dw to reduce feed intake or lower feed restriction and improve reproductive performance in heavy female broiler parent stock. Two separate experiments were conducted. All female parent stocks were mated to Cornish males, and fertile eggs were collected. In the first experiment, eggs were incubated for 21 d under standard conditions to determine, during final stages of incubation, corticosterone and thyroid hormone levels (triiodothyronine, T3; thyroxine, T4) in embryos and hatchlings, CO2 partial pressure (pCO2), and O2 partial pressure (pO2) in air cells, heat production by eggs and 1-d-old weights. In the second experiment, eggs were incubated for 21 d to compare chick quality, chick weights at 1 d of age, and broiler growth to 7 and 41 d. Average egg weights were higher for the S and L lines than the E line, but weight loss during incubation was lowest for the E line. Plasma T3 and T3/T4 ratio was similar between lines at IP, but corticosterone was higher in the S line. At hatch, T3/T4 ratio was higher in the S line compared with

  19. Use of Direct LAMP Screening of Broiler Fecal Samples for Campylobacter jejuni and Campylobacter coli in the Positive Flock Identification Strategy

    PubMed Central

    Sabike, Islam I.; Uemura, Ryoko; Kirino, Yumi; Mekata, Hirohisa; Sekiguchi, Satoshi; Okabayashi, Tamaki; Goto, Yoshitaka; Yamazaki, Wataru

    2016-01-01

    Rapid identification of Campylobacter-positive flocks before slaughter, following freezing and heat treatment for the Campylobacter-positive carcasses at the slaughterhouses is an effective control strategy against foodborne campylobacteriosis. We evaluated a loop-mediated isothermal amplification (LAMP) assay for the direct screening of naturally contaminated chicken cloacal swabs for C. jejuni/C. coli to compare this assay with conventional quantitative culture methods. In a comparison study of 165 broilers, the LAMP assay showed 82.8% (48/58 by conventional culture) sensitivity, 100% (107/107) specificity, 100% (48/48) positive predictive value (PPV), and 91.5% (107/117) negative predictive value (NPV). In a comparison of 55 flocks, LAMP showed 90.5% (19/21) sensitivity, 100% (34/34) specificity, 100% (19/19) PPV, and 94.4% (34/36) NPV. In the cumulative total of 28 farm-level comparisons, LAMP showed 100% (12/12) sensitivity, 100% (16/16) specificity, 100% (12/12) PPV, and 100% (16/16) NPV. The LAMP assay required less than 90 min from the arrival of the fecal samples to final results in the laboratory. This suggests that the LAMP assay will facilitate the identification of C. jejuni/C. coli-positive broiler flocks at the farm level or in slaughterhouses before slaughtering, which would make it an effective tool in preventing the spread of Campylobacter contamination. PMID:27746777

  20. Effect of bacteriophage application on Campylobacter jejuni loads in commercial broiler flocks.

    PubMed

    Kittler, Sophie; Fischer, Samuel; Abdulmawjood, Amir; Glünder, Gerhard; Klein, Günter

    2013-12-01

    Campylobacteriosis is the most frequent food-borne human enteritis. The major source for infection with Campylobacter spp. is broiler meat. Risk assessments consider the reduction of Campylobacter in primary production to be most beneficial for human health. The aim of this study was to test the efficacy of a bacteriophage application under commercial conditions which had proved to be effective in previous noncommercial studies under controlled experimental conditions. A phage cocktail for Campylobacter reduction was tested on three commercial broiler farms each with a control and an experimental group. Colonization of Campylobacter was confirmed prior to phage application in fecal samples. Subsequently, a phage cocktail was applied via drinking water in the experimental group (log10 5.8 to 7.5 PFU/bird). One day after phage application, Campylobacter counts of one experimental group were reduced under the detection limit (<50 CFU/g, P=0.0140) in fecal samples. At slaughter, a significant reduction of >log10 3.2 CFU/g cecal content compared to the control was still detected (P=0.0011). No significant reduction was observed in the experimental groups of the other trials. However, a significant drop in cecal Campylobacter counts occurred in a phage-contaminated control. These results suggest that maximum reduction of Campylobacter at the slaughterhouse might be achieved by phage application 1 to 4 days prior to slaughter.

  1. Transmission dynamics of extended-spectrum β-lactamase and AmpC β-lactamase-producing Escherichia coli in a broiler flock without antibiotic use.

    PubMed

    Huijbers, Patricia M C; Graat, Elisabeth A M; van Hoek, Angela H A M; Veenman, Christiaan; de Jong, Mart C M; van Duijkeren, Engeline

    2016-09-01

    Extended-spectrum and AmpC β-lactamase-producing Escherichia coli (ESBL/AmpC-EC) are found throughout the broiler production pyramid. Transmission of resistance between broilers and humans could occur at any point, representing a potential public health issue. Insight in farm transmission dynamics could provide a basis for control, leading to fewer contaminated broilers. The aim was quantifying transmission rates and routes of ESBL/AmpC-EC, and specific phylogenetic groups, in an organic broiler flock without antibiotic use. In each of two consecutive production rounds, 80 randomly chosen broilers were followed individually. Cloacal swabs from these, 20 other randomly chosen broilers, and 11 environmental samples were taken at several moments from arrival till slaughter. ESBL/AmpC-EC were isolated by selective pre-enrichment, and ESBL/AmpC-genes and E. coli phylogenetic groups were determined. Transmission parameters (β) were estimated using a Generalised Linear Model with a susceptible-infectious-susceptible model. Effect of direct broiler contact as compared to contact through the environment and previous carriage c.q. infectious status and their interaction were included as explanatory variables. Multiplying β by the length of the infectious period gives the reproduction ratio (R). On day 1, prevalence was 28.8% (95%CI 19.2-40.0%) and 0.0% (95%CI 0.0-4.5%) among individually followed broilers, in round 1 and 2 respectively. In round 2, the environment was positive before arrival of day-old chicks. After 3 days, almost 100% of broilers and environmental samples were positive in both rounds. Most samples were positive for CTX-M-1 group genes, and A1 and B1 were predominant phylogenetic groups. From day 3 there was a shift towards more phylogenetic groups. R was 1.70 (95%CI 0.55-5.25) for total ESBL/AmpC-EC. Risk for broilers to become infectious was lower if previously infectious (βpreviously infectious=0.02 vs. βnot previously infectious=3.41; P<0.0001). For

  2. Quantitative Estimation of the Number of Contaminated Hatching Eggs Released from an Infected, Undetected Turkey Breeder Hen Flock During a Highly Pathogenic Avian Influenza Outbreak.

    PubMed

    Malladi, Sasidhar; Weaver, J Todd; Alexander, Catherine Y; Middleton, Jamie L; Goldsmith, Timothy J; Snider, Timothy; Tilley, Becky J; Gonder, Eric; Hermes, David R; Halvorson, David A

    2015-09-01

    The regulatory response to an outbreak of highly pathogenic avian influenza (HPAI) in the United States may involve quarantine and stop movement orders that have the potential to disrupt continuity of operations in the U.S. turkey industry--particularly in the event that an uninfected breeder flock is located within an HPAI Control Area. A group of government-academic-industry leaders developed an approach to minimize the unintended consequences associated with outbreak response, which incorporates HPAI control measures to be implemented prior to moving hatching eggs off of the farm. Quantitative simulation models were used to evaluate the movement of potentially contaminated hatching eggs from a breeder henhouse located in an HPAI Control Area, given that active surveillance testing, elevated biosecurity, and a 2-day on-farm holding period were employed. The risk analysis included scenarios of HPAI viruses differing in characteristics as well as scenarios in which infection resulted from artificial insemination. The mean model-predicted number of internally contaminated hatching eggs released per movement from an HPAI-infected turkey breeder henhouse ranged from 0 to 0.008 under the four scenarios evaluated. The results indicate a 95% chance of no internally contaminated eggs being present per movement from an infected house before detection. Sensitivity analysis indicates that these results are robust to variation in key transmission model parameters within the range of their estimates from available literature. Infectious birds at the time of egg collection are a potential pathway of external contamination for eggs stored and then moved off of the farm; the predicted number of such infectious birds was estimated to be low. To date, there has been no evidence of vertical transmission of HPAI virus or low pathogenic avian influenza virus to day-old poults from hatching eggs originating from infected breeders. The application of risk analysis methods was beneficial

  3. Quantitative Estimation of the Number of Contaminated Hatching Eggs Released from an Infected, Undetected Turkey Breeder Hen Flock During a Highly Pathogenic Avian Influenza Outbreak.

    PubMed

    Malladi, Sasidhar; Weaver, J Todd; Alexander, Catherine Y; Middleton, Jamie L; Goldsmith, Timothy J; Snider, Timothy; Tilley, Becky J; Gonder, Eric; Hermes, David R; Halvorson, David A

    2015-09-01

    The regulatory response to an outbreak of highly pathogenic avian influenza (HPAI) in the United States may involve quarantine and stop movement orders that have the potential to disrupt continuity of operations in the U.S. turkey industry--particularly in the event that an uninfected breeder flock is located within an HPAI Control Area. A group of government-academic-industry leaders developed an approach to minimize the unintended consequences associated with outbreak response, which incorporates HPAI control measures to be implemented prior to moving hatching eggs off of the farm. Quantitative simulation models were used to evaluate the movement of potentially contaminated hatching eggs from a breeder henhouse located in an HPAI Control Area, given that active surveillance testing, elevated biosecurity, and a 2-day on-farm holding period were employed. The risk analysis included scenarios of HPAI viruses differing in characteristics as well as scenarios in which infection resulted from artificial insemination. The mean model-predicted number of internally contaminated hatching eggs released per movement from an HPAI-infected turkey breeder henhouse ranged from 0 to 0.008 under the four scenarios evaluated. The results indicate a 95% chance of no internally contaminated eggs being present per movement from an infected house before detection. Sensitivity analysis indicates that these results are robust to variation in key transmission model parameters within the range of their estimates from available literature. Infectious birds at the time of egg collection are a potential pathway of external contamination for eggs stored and then moved off of the farm; the predicted number of such infectious birds was estimated to be low. To date, there has been no evidence of vertical transmission of HPAI virus or low pathogenic avian influenza virus to day-old poults from hatching eggs originating from infected breeders. The application of risk analysis methods was beneficial

  4. Effects of environmental temperature and dietary manganese on egg production performance, egg quality, and some plasma biochemical traits of broiler breeders.

    PubMed

    Zhu, Y W; Xie, J J; Li, W X; Lu, L; Zhang, L Y; Ji, C; Lin, X; Liu, H C; Odle, J; Luo, X G

    2015-07-01

    An experiment was conducted to investigate the effects of environmental temperature and dietary Mn on egg production performance, egg quality, and some plasma biochemical traits of broiler breeders. A completely randomized factorial design involved 2 environmental temperatures (a normal temperature, 21 ± 1°C, and a high temperature, 32 ± 1°C) × 3 dietary Mn treatments (a Mn-unsupplemented corn–soybean meal basal diet or the basal diet supplemented with 120 mg of Mn/kg of diet as either MnSO4·H2O or manganese proteinate). There were 6 treatments with 6 replicates (4 birds per replicate). High temperature decreased egg weight (P < 0.0001), laying rate (P < 0.0001), egg yield (P < 0.0001), feed intake (P < 0.0001), egg:feed ratio (P < 0.0001), eggshell strength (P < 0.05) and thickness (P < 0.0001), plasma triiodothyronine level (P < 0.05), and alkaline phosphatase activity (P < 0.04) whereas it increased rectal temperature (P < 0.0001); plasma malondialdehyde level (P < 0.02); and activities (P < 0.002) of lactic dehydrogenase, aspartate aminotransferase, and creatine kinase. Broiler breeders fed the diets supplemented with Mn regardless of source had greater (P < 0.05) eggshell strength and lower (P ≤ 0.05) plasma triiodothyronine level and protein carbonyl content than those fed the control diet. The broiler breeders fed the diet supplemented with the organic Mn had greater (P < 0.01) eggshell thickness than those fed the control diet. There were interactions (P < 0.05) between environmental temperature and dietary Mn in laying rate, egg yield, feed intake, and egg:feed ratio. Under normal temperature, dietary Mn did not affect the above 4 parameters; however, under high temperature, broiler breeders fed the diet supplemented with the organic Mn showed greater (P < 0.03) improvements in these 4 parameters than those fed the control diet. The results from this study indicated that high temperature significantly impaired egg production performance and

  5. Effect of warm drinking water on the performance and immunological responses of broiler breeder hens raised at low air temperatures.

    PubMed

    Spinu, M; Degen, A A; Rosenstrauch, A

    1993-05-01

    1. The effect of warmed drinking water on the performance and immunological responses of broiler breeder hens maintained at low air temperatures (5.0 degrees to 12.9 degrees C) was tested. From 22 weeks of age hens (mean body mass = 2.4 kg) were offered either warm water (27.7 degrees C; WARM; n = 24) or tap water (12.7 degrees C; CONR; n = 24) twice daily for a total time of 2.5 h or tap water ad libitum (CONA; n = 16). Food was restricted for all hens. 2. Daily water intake in the WARM hens (103 ml/kg) was similar to that of the CONR (93 ml/kg) and CONA hens (106 ml/kg). 3. There were no significant differences in either body mass change or egg production among treatment groups. 4. There was no difference among groups in heterophil/lymphocyte ratios. Similarly, there was no difference among groups in either phagocytic activity or wattle index after phytohaemagglutinin (PHA) injection. Total and IgG antibody titres to SRBC tended to be highest in the WARM hens and these titres were significantly higher than in CONR hens 14 d after challenge.

  6. Molecular characterization of infectious bursal disease viruses detected in vaccinated commercial broiler flocks in Lusaka, Zambia.

    PubMed

    Ndashe, Kunda; Simulundu, Edgar; Hang'ombe, Bernard M; Moonga, Ladslav; Ogawa, Hirohito; Takada, Ayato; Mweene, Aaron S

    2016-03-01

    Infectious bursal disease (IBD) is an acute, highly contagious, and immunosuppressive viral disease of young chickens and remains one of the economically most important diseases threatening the poultry industry worldwide. In this study, 16 and 11 nucleotide sequences of the VP2 hypervariable region (VP2-HVR) and part of VP1, respectively, of IBD virus (IBDV) detected in vaccinated broiler chickens in Lusaka in 2012 were determined. Phylogenetic analysis revealed that these Zambian IBDVs separated into three genotypes of very virulent (VV) IBDVs. Although the majority of these viruses belonged to the African VV type (VV1), which consisted of viruses from West Africa, South Africa and Zambia, one virus belonged to the East African VV type (VV2). Interestingly, a Zambian IBDV belonging to the VV3 genotype (composed of viruses from several continents) clustered with attenuated vaccine strains. Although sequence analysis of VP2-HVR showed that all detected Zambian IBDVs had conserved putative virulence marker amino acids (i.e., 222A, 242I, 256I, 294I and 299S), one virus had two unique amino acid substitutions, N280S and E300A. This study demonstrates the diversity of Zambian IBDVs and documents for the first time the possible involvement of attenuated vaccine strains in the epidemiology of IBD in Zambia. Strict biosecurity of poultry farms, monitoring of live vaccine use in the field, surveillance and characterization of IBDV in poultry and development of a vaccine from local or regional IBDV field strains are recommended for improved IBD control in Zambia.

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

    PubMed Central

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

    2016-01-01

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

  8. The cysteine, total sulfur amino acid, tyrosine, phenylalanine + tyrosine, and non-essential amino acid maintenance requirements of broiler breeders.

    PubMed

    Ekmay, R D; Mei, S J; Sakomura, N K; Coon, C N

    2016-06-01

    Two hundred and fifty Cobb-Vantress broiler breeders were used to determine the maintenance requirement and efficiency of utilization of dietary Cys, Tyr, and non-essential amino acids (AA) in a 21-day experiment. The breeders were fed crystalline amino acid diets containing graded levels of Cys or Tyr representing 0, 10, 20, 30, and 40% of their suggested requirement level with all other amino acids maintained at 40% of their suggested requirement level. To determine the non-essential AA maintenance requirement, graded levels of non-essential AA were provided by glutamic acid to represent 12, 19, 26, 33, and 40% of the ideal level of glutamic acid with all other amino acids maintained at their maintenance requirement level. The total sulfur amino acid (TSAA) and Phe + Tyr requirements were calculated by combining Cys and Tyr results, respectively, with previously determined Met and Phe, respectively. The slope of Cys, Tyr, and non-essential AA accretion regression line indicated that 29% Cys, 24% TSAA, 21% Tyr, 20% Phe + Tyr, and 9% non-essential AA of crystalline amino acids were retained. The Cys requirement for zero protein accretion was calculated to be 30.48 mg/d or 17.006 mg/ kgBW(0.75)/d or 75.426 mg/kgCP/d. The TSAA requirement for zero accretion was calculated to be 132.25 mg/b/d, 71.48 mg/kgBW(0.75)/d, and 307.55 mg/kgCP/d. The Tyr requirement for zero protein accretion was calculated to be 65.907 mg/d or 37.233 mg/ kgBW(0.75)/d or 175.566 mg/kgCP/d. The Phe + Tyr requirement for zero protein accretion was calculated to be 352.18 mg/b/d, 190.37 mg/kgBW(0.75)/d, and 749.33 mg/kgCP/d. The non-essential AA requirement for zero protein accretion was calculated to be 3715.194 mg/d or 2003.155 mg/kgBW(0.75)/d or 9452.954 mg/kgCP/d.

  9. Age-related changes in meat tenderness and tissue pentosidine: effect of diet restriction and aminoguanidine in broiler breeder hens.

    PubMed

    Iqbal, M; Kenney, P B; Klandorf, H

    1999-09-01

    The nonenzymatic glycosylation of tissue protein contributes to the formation of crosslinks that leads to structural and functional deterioration in the long-lived tissue protein, collagen. The accumulation of these crosslinks thus contributes to the objectionable toughness of meat from aged animals, decreases its economic value, and limits its use in whole muscle foods. The objectives of this study were to determine the effectiveness of diet restriction and the crosslinking inhibitor, aminoguanidine (AG), on reducing the accumulation of crosslinks, thereby improving meat tenderness in broiler breeder hens. The glycoxidation product, pentosidine, was also measured in skin (Ps) to determine whether changes in its concentrations correlated with the changes in shear value (SV). Chicks (n = 450) were randomly assigned to four treatment groups from 8 to 125 wk after hatch: ad libitum (AL), diet restricted (DR), AL and DR groups supplemented with 400 ppm AG each (AL+AG and DR+AG, respectively). Shear value was measured with an Instron Universal Mechanical Machine. Skin pentosidine was isolated by reverse phase HPLC. There was an age-related, linear increase in SV (P<0.0001, r = 0.96), which correlated (r = 0.86) with the age-related increase in Ps in AL hens. Diet restriction retarded SV (P<0.0001) over the sampling period. In general, SV values for AL+AG were similar to those measured in DR, whereas no additive effect was observed for AG in DR birds. It was concluded that there was a linear increase in meat toughness (SV) with age that correlates with the accumulation of Ps, and that the decline in meat tenderness can be retarded by DR or AG. Secondly, the effect of DR on accumulation of Ps was so pronounced that AG supplementation did not further enhance this effect.

  10. Effect of long-term food restriction on pituitary sensitivity to cLHRH-I in broiler breeder females.

    PubMed

    Bruggeman, V; Onagbesan, O; Vanmontfort, D; Berghman, L; Verhoeven, G; Decuypere, E

    1998-11-01

    The effect of long-term food restriction on the sensitivity of the pituitary to exogenously administered chicken luteinizing hormone releasing hormone I (cLHRH-I) was investigated in three groups of broiler breeder females fed ad libitum, fed a restricted quantity of food or fed a restricted quantity of food to obtain an intermediate body weight between those of the first two groups. At 16 weeks of age, basal FSH release was higher in ad libitum fed birds, culminating in ovarian development and subsequent oestradiol production by the small follicles. At this age, LH secretion was independent of ovarian feedback factors. In all groups, cLHRH-I was most active in releasing LH in intact and ovariectomized animals and, to a lesser extent, in releasing FSH in ovariectomized birds. At 39 weeks of age, basal FSH concentrations were similar among intact animals of all groups, whereas LH concentrations differed among groups, with higher values in the restricted birds. This food effect was enhanced in ovariectomized birds. Furthermore, the high response to cLHRH-I in the ovariectomized, restricted birds compared with the ad libitum, ovariectomized group suggests an improved sensitivity of the hypothalamic-pituitary axis. In conclusion, birds fed ad libitum showed the highest responsiveness to ovarian factors and to cLHRH-I in releasing FSH in the period before sexual maturity. No effect of amount of feeding could be observed for LH. However, during the egg laying period, LH release by cLHRH-I was highly dependent on amount of feeding and on ovarian feedback regulation. This finding indicates that the amount of feeding can modify the sensitivity of the pituitary to cLHRH-I, and possibly to gonadal hormones, during the laying period.

  11. Dietary vitamin A supplementation improved reproductive performance by regulating ovarian expression of hormone receptors, caspase-3 and Fas in broiler breeders.

    PubMed

    Chen, Fang; Jiang, Zongyong; Jiang, Shouqun; Li, Long; Lin, Xiajing; Gou, Zongyong; Fan, Qiuli

    2016-01-01

    The effects of dietary vitamin A (VA) supplementation on reproductive performance, VA deposition, and potential mechanisms of action were studied in Chinese yellow-feathered broiler breeders. A total of 528 yellow-feathered broiler breeders that were 46 wk old were fed a corn-soybean meal basal diet supplemented with 0; 5,400; 10,800; or 21,600 IU/kg VA for 9 wk. Each dietary treatment had 6 replicates with 22 birds per replicate. After 7 wk of treatment, 60 settable eggs per replicate were collected for hatching. The results showed that dietary VA improved the laying rate, egg-to-feed ratio, and hatch weight of offspring (P < 0.05). Hepatic retinyl palmitate in broiler breeders and hatchlings (within 12 h) increased with increasing VA (P < 0.05). VA supplementation increased insulin-like growth factor 1 (IGF-I) receptor transcripts in the ovarian stroma and the walls of yellow follicles, follicle stimulating hormone (FSH) receptor expression in the walls of white and yellow follicles, and luteinizing hormone (LH) receptor and growth hormone (GH) receptor transcripts in the walls of yellow follicles (P < 0.05). Caspase-3 and Fas mRNA levels in the ovarian stroma and the walls of white and yellow follicles decreased with VA supplementation (P < 0.05). The relative expression of retinol dehydrogenase 10 (RDH10) transcripts in the walls of white follicles increased with 5,400 IU/kg VA supplementation (P < 0.05). Supplemental 21,600 IU/kg VA increased cytochrome P450 26A1 (CYP26A1) transcripts in the ovarian stroma and the walls of white follicles (P < 0.05). Dietary VA elevated retinoic acid receptor α (RARα) expression in the ovarian stroma and the walls of yellow follicles and retinoid X receptor α (RXRα) expression in the walls of yellow follicles. It was concluded that VA supplementation improved reproductive performance and hepatic storage of VA, and this was associated with the regulation of ovarian hormone receptor expression and suppression of apoptosis

  12. Supplementation of dietary vitamins, protein and probiotics on semen traits and immunohistochemical study of pituitary hormones in zinc-induced molted broiler breeders.

    PubMed

    Khan, Rifat Ullah; Rahman, Zia-ur-; Javed, Ijaz; Muhammad, Faqir

    2013-09-01

    The purpose of this study was to investigate the effect of dietary vitamin E and vitamin C, probiotics mixture and protein level and their combination on semen quality and immunohistochemical study of some pituitary hormones in male broiler breeders. One hundred and eighty male broiler breeders 65 weeks old were divided into six groups by completely randomized design. The birds were subjected to zinc-induced molt by mixing zinc oxide at the rate of 3000mg/kg in the feed. After molting, one group was fed control diet (CP16%). The other groups were fed vitamin E (100IU/kg), vitamin C (500IU/kg), probiotics (50mg/L of drinking water), protein (CP14%) and combination of these components. These treatments were given for five weeks. After the feeding period, semen samples were taken and analyzed for semen volume, sperm concentration, motility and dead sperm percentage. Pituitary samples were collected from three birds per replicate and were processed for immunohistochemical study. The results of semen quality parameters revealed that semen volume and sperm motility were significantly high in the vitamin E fed group, while the dead sperm percentage decreased significantly in the vitamin C group. The morphometric analysis revealed that compared to other groups, vitamin E caused a significant increase in the size and area of FSH, LH gonadotropes and lactotropes. These results showed that vitamin E alone may play some role in the enhancement of semen quality and growth of gonadotropes and lactotropes.

  13. Different sources of maternal selenium affect selenium retention, antioxidant status, and meat quality of 56-day-old offspring of broiler breeders.

    PubMed

    Zhang, L; Wang, Y X; Zhou, Y; Zheng, L; Zhan, X A; Pu, Q H

    2014-09-01

    The maternal effect of different Se source in offspring of young broiler breeders has been reported, but the lasting maternal effect of different sources of Se on offspring of breeders has received limited attention, so this study was conducted to investigate the effects of different maternal Se sources on Se retention, antioxidant status, and meat quality of 56-d-old offspring of broiler breeders. A total of two hundred forty 39-wk-old Lingnan Yellow broiler breeders were randomly distributed into 2 treatments, each of which was replicated 3 times with 40 birds per replicate, with a 14-d pretreatment and 56-d trial period. The treatments were fed a basal corn-soybean diet (0.04 mg∙kg⁻¹ Se) supplemented with 0.3 mg∙kg⁻¹ sodium selenite (SS) or selenomethionine (Se-Met). Fertile eggs were collected for incubation, after which 180 healthy chicks from each treatment were selected and randomly allocated into 3 replicates, with 60 birds per replicate. All the chicks were fed the same basal diet (0.04 mg∙kg⁻¹ Se) for 56 d. The Se concentrations in serum and tissues (liver, kidney, and breast muscle) of the 56-d-old offspring were significantly (P < 0.01) increased by maternal Se-Met intake compared with maternal SS intake. The antioxidant status of the 56-d-old offspring was greatly improved by maternal Se-Met supplementation in contrast with maternal SS supplementation, which was shown by increased glutathione peroxidase activity in serum and breast muscle (P < 0.01), glutathione concentration in serum (P < 0.05), and total antioxidant capability in pancreas (P < 0.01), as well as cytosolic glutathione peroxidase mRNA abundance in breast muscle, liver (P < 0.01), and pancreas (P < 0.05). The maternal Se-Met treatment was more effective in maintaining the shape of liver and pancreas cells, cell nuclei, chromatin, as well as cell membrane structure, and more organelles were observed in liver cells. The maternal Se-Met treatment had significant (P < 0

  14. A field study on the significance of vaccination against infectious bursal disease virus (IBDV) at the optimal time point in broiler flocks with maternally derived IBDV antibodies.

    PubMed

    Block, Hermann; Meyer-Block, Karen; Rebeski, Dierk E; Scharr, Heike; de Wit, Sjaak; Rohn, Karl; Rautenschlein, Silke

    2007-10-01

    The right strategy for infectious bursal disease (IBD) control and its success rate under field conditions depends on hygiene management, IBD field pressure, level and variation in maternally derived IBD antibodies, and the IBD vaccine strains to be used. Usually, standard vaccination programmes are used, which are not always adapted to the specific conditions on the farm and to the immune status of chickens. Employing the "Deventer formula" may help to estimate the optimal time for vaccination for a specific flock based on the maternally derived antibody level, its variation, the genetic background of the chicken, and the IBD vaccine strain. Two field studies with 16 or 20 commercial broiler flocks were conducted, applying an intermediate IBD vaccine before, at the best, and after the estimated optimal vaccination time estimated by the "Deventer formula". These studies showed that flocks IBD-vaccinated between 1 day before, at, or up to 3 days after the estimated optimal time point developed detectable humoral immunity up to 14 days post vaccination. If birds had been vaccinated more than 1 day before the calculated optimal vaccination date, the humoral immune response was delayed or non-detectable until slaughter. The induction of humoral immunity correlated with the incidence of bursa lesions and IBDV detection by reverse transcriptase-polymerase chain reaction. As indicated in this study, under field conditions bursa lesions may develop later than predicted based on experimental experiences. The late incidence of bursa lesions after vaccination may be confused with field virus-induced lesions, in which case sequencing may offer a valuable tool for differentiation. PMID:17899465

  15. Effects of different limestone particle sizes in the diet of broiler breeders post molting on their performance, egg quality, incubation results, and pre-starter performance of their progeny.

    PubMed

    Bueno, I J M; Surek, D; Rocha, C; Schramm, V G; Muramatsu, K; Dahlke, F; Maiorka, A

    2016-04-01

    An experiment was conducted to test the hypothesis that a coarse limestone diet improves productivity, reproductive performance and the calcium utilization of molted broiler breeders. In total, 640 broiler breeder females, 73-week-old and sixty-four 27-week-old cockerels, Cobb 500, were evaluated during 10 weeks, according to a randomized block design composed of 4 treatments with 8 replicates each. Treatments consisted of diets with the inclusion of 100% fine limestone-fine PS (0.2 mm GMD-geometric mean diameter); PS1: 30% fine limestone+70% limestone with 1.0 mm GMD; PS2: 30% fine limestone+70% limestone with 2.0 mm GMD; and PS3: 30% fine limestone+70% limestone with 3.0 mm GMD. Calcium retention in the gizzard of the breeders, bone characteristics, and breeder performance, egg characteristics, eggshell quality, incubation performance, chick quality and yield, chick pre-starter live performance, and chick bone characteristics were determined. There was no significant difference (P>0.05) in the rate of lay, percentage of non-settable eggs, egg weight, egg shape index, egg specific gravity, eggshell weight, thickness, and percentage hatchability and egg weight loss of broiler breeders fed with diets with different limestone particle sizes. The chick quality and yield, chick pre-starter live performance, and chick bone characteristics were not affected (P>0.05) by any of the limestone particle sizes. It was concluded that live and reproductive performance parameters of broiler breeders post molting is not affected by limestone particle size in the feed. PMID:26769267

  16. Morphometric Documentation of a High Prevalence of Left Ventricular Dilated Cardiomyopathy in Both Clinically Normal and Cyanotic Mature Commercial Broiler Breeder Roosters with Comparisons to Market-Age Broilers.

    PubMed

    Wilson, Floyd D; Magee, Danny L; Jones, Kelli H; Baravik-Munsell, Erica; Cummings, Timothy S; Wills, Robert W; Pace, Lanny W

    2016-09-01

    Previous studies documented the common occurrence of transitory cyanosis and echocardiographic aortic insufficiency in mature commercial broiler breeder roosters. During further investigations, we observed a high prevalence of hearts exhibiting extensive dilation of the left ventricle chamber compatible with dilated left ventricular cardiomyopathy present in both cyanotic and normal subpopulations. We conducted quantitative studies focused on documentation of cardiac ventricle parameters by using simple gross morphometric methods performed on formalin-fixed hearts obtained from both clinically normal roosters and those exhibiting variable transitory cyanosis, echocardiographic aortic insufficiency, or both. A high prevalence of often dramatic left ventricular dilation reflected in enlarged left ventricular chamber areas and elevated left ventricle-to-total ventricle area ratios was morphometrically documented. However, no statistically significant differences in the occurrence of ventricular abnormalities were observed between normal and cyanotic roosters. Age-associated changes were also demonstrated by comparative morphometric studies on hearts from normal market-age broilers (average age of 7 wk) and those of mature roosters (average age of 42 wk). Elevation in both left and right ventricular weight-to-total heart weight ratios dramatically increased with aging. In addition, values (average ± SD) for the left ventricle chamber area-to-total ventricle area ratios increased from 3.2 ± 2.0% in broilers up to 10.0 ± 8.8% in roosters. None of the normal broilers studied demonstrated left ventricular volume ratios above 10%, whereas 33% of the roosters had left ventricular volume ratios above 10%, including 13% with ratios of 20% or higher. However, the left ventricle wall area-to-body weight ratios were much closer for the two age groups (0.85 ± 0.18 cm(2)/kg in broilers and 0.79 ± 0.13 cm(2)/kg in roosters). Also, the standard right ventricle-to-total ventricle

  17. Morphometric Documentation of a High Prevalence of Left Ventricular Dilated Cardiomyopathy in Both Clinically Normal and Cyanotic Mature Commercial Broiler Breeder Roosters with Comparisons to Market-Age Broilers.

    PubMed

    Wilson, Floyd D; Magee, Danny L; Jones, Kelli H; Baravik-Munsell, Erica; Cummings, Timothy S; Wills, Robert W; Pace, Lanny W

    2016-09-01

    Previous studies documented the common occurrence of transitory cyanosis and echocardiographic aortic insufficiency in mature commercial broiler breeder roosters. During further investigations, we observed a high prevalence of hearts exhibiting extensive dilation of the left ventricle chamber compatible with dilated left ventricular cardiomyopathy present in both cyanotic and normal subpopulations. We conducted quantitative studies focused on documentation of cardiac ventricle parameters by using simple gross morphometric methods performed on formalin-fixed hearts obtained from both clinically normal roosters and those exhibiting variable transitory cyanosis, echocardiographic aortic insufficiency, or both. A high prevalence of often dramatic left ventricular dilation reflected in enlarged left ventricular chamber areas and elevated left ventricle-to-total ventricle area ratios was morphometrically documented. However, no statistically significant differences in the occurrence of ventricular abnormalities were observed between normal and cyanotic roosters. Age-associated changes were also demonstrated by comparative morphometric studies on hearts from normal market-age broilers (average age of 7 wk) and those of mature roosters (average age of 42 wk). Elevation in both left and right ventricular weight-to-total heart weight ratios dramatically increased with aging. In addition, values (average ± SD) for the left ventricle chamber area-to-total ventricle area ratios increased from 3.2 ± 2.0% in broilers up to 10.0 ± 8.8% in roosters. None of the normal broilers studied demonstrated left ventricular volume ratios above 10%, whereas 33% of the roosters had left ventricular volume ratios above 10%, including 13% with ratios of 20% or higher. However, the left ventricle wall area-to-body weight ratios were much closer for the two age groups (0.85 ± 0.18 cm(2)/kg in broilers and 0.79 ± 0.13 cm(2)/kg in roosters). Also, the standard right ventricle-to-total ventricle

  18. Measuring motivation for appetitive behaviour: food-restricted broiler breeder chickens cross a water barrier to forage in an area of wood shavings without food.

    PubMed

    Dixon, Laura M; Brocklehurst, Sarah; Sandilands, Vicky; Bateson, Melissa; Tolkamp, Bert J; D'Eath, Rick B

    2014-01-01

    Broiler breeders (parents of meat chickens) are selected for fast growth and become obese if fed ad libitum. To avoid this and maintain good health and reproductive ability, they are feed restricted to about 1/3 of what they would eat ad libitum. As a result, they experience chronic hunger and exhibit abnormal behaviour patterns that may indicate stress and frustration. One approach to measuring hunger is to observe how much birds will work, such as pecking a key, for access to more or different types of food. However, the sight, smell, and feedback from consumption of the feed reward changes the context and may artificially raise feeding motivation. To avoid this, we tested broiler breeders in an apparatus in which they could work for access to a wooden platform covered in wood shavings by crossing a water runway which increased in length and depth in 8 successive tests. In the wood shavings area, they could perform exploratory and foraging behaviour (the appetitive phase of feeding) but were never rewarded with feed. Sixty birds were divided into three feed quantity treatments: commercial restriction (R), and twice (2R) or three times (3R) this amount. Overall, birds fed R worked harder to reach the wood shavings area (reached it in a larger number of tests) than 2R and 3R birds (P<0.001). More restricted birds took less time to reach the area (P<0.001, R<2R<3R) and spent more time foraging while there (P<0.001, R>2R>3R). This indicates that restricted-fed birds were hungry and willing to work for the opportunity to forage even though food was never provided, suggesting that their motivation to perform the appetitive component of feeding behaviour (foraging/food searching) was sufficient to sustain their response. Thus food restriction in broiler breeders is a welfare concern. However these methods could be used to test alternative feeding regimes to attempt to find ways of alleviating hunger while still maintaining healthy growth and reproduction in these birds.

  19. Measuring motivation for appetitive behaviour: food-restricted broiler breeder chickens cross a water barrier to forage in an area of wood shavings without food.

    PubMed

    Dixon, Laura M; Brocklehurst, Sarah; Sandilands, Vicky; Bateson, Melissa; Tolkamp, Bert J; D'Eath, Rick B

    2014-01-01

    Broiler breeders (parents of meat chickens) are selected for fast growth and become obese if fed ad libitum. To avoid this and maintain good health and reproductive ability, they are feed restricted to about 1/3 of what they would eat ad libitum. As a result, they experience chronic hunger and exhibit abnormal behaviour patterns that may indicate stress and frustration. One approach to measuring hunger is to observe how much birds will work, such as pecking a key, for access to more or different types of food. However, the sight, smell, and feedback from consumption of the feed reward changes the context and may artificially raise feeding motivation. To avoid this, we tested broiler breeders in an apparatus in which they could work for access to a wooden platform covered in wood shavings by crossing a water runway which increased in length and depth in 8 successive tests. In the wood shavings area, they could perform exploratory and foraging behaviour (the appetitive phase of feeding) but were never rewarded with feed. Sixty birds were divided into three feed quantity treatments: commercial restriction (R), and twice (2R) or three times (3R) this amount. Overall, birds fed R worked harder to reach the wood shavings area (reached it in a larger number of tests) than 2R and 3R birds (P<0.001). More restricted birds took less time to reach the area (P<0.001, R<2R<3R) and spent more time foraging while there (P<0.001, R>2R>3R). This indicates that restricted-fed birds were hungry and willing to work for the opportunity to forage even though food was never provided, suggesting that their motivation to perform the appetitive component of feeding behaviour (foraging/food searching) was sufficient to sustain their response. Thus food restriction in broiler breeders is a welfare concern. However these methods could be used to test alternative feeding regimes to attempt to find ways of alleviating hunger while still maintaining healthy growth and reproduction in these birds

  20. Measuring Motivation for Appetitive Behaviour: Food-Restricted Broiler Breeder Chickens Cross a Water Barrier to Forage in an Area of Wood Shavings without Food

    PubMed Central

    Dixon, Laura M.; Brocklehurst, Sarah; Sandilands, Vicky; Bateson, Melissa; Tolkamp, Bert J.; D'Eath, Rick B.

    2014-01-01

    Broiler breeders (parents of meat chickens) are selected for fast growth and become obese if fed ad libitum. To avoid this and maintain good health and reproductive ability, they are feed restricted to about 1/3 of what they would eat ad libitum. As a result, they experience chronic hunger and exhibit abnormal behaviour patterns that may indicate stress and frustration. One approach to measuring hunger is to observe how much birds will work, such as pecking a key, for access to more or different types of food. However, the sight, smell, and feedback from consumption of the feed reward changes the context and may artificially raise feeding motivation. To avoid this, we tested broiler breeders in an apparatus in which they could work for access to a wooden platform covered in wood shavings by crossing a water runway which increased in length and depth in 8 successive tests. In the wood shavings area, they could perform exploratory and foraging behaviour (the appetitive phase of feeding) but were never rewarded with feed. Sixty birds were divided into three feed quantity treatments: commercial restriction (R), and twice (2R) or three times (3R) this amount. Overall, birds fed R worked harder to reach the wood shavings area (reached it in a larger number of tests) than 2R and 3R birds (P<0.001). More restricted birds took less time to reach the area (P<0.001, R<2R<3R) and spent more time foraging while there (P<0.001, R>2R>3R). This indicates that restricted-fed birds were hungry and willing to work for the opportunity to forage even though food was never provided, suggesting that their motivation to perform the appetitive component of feeding behaviour (foraging/food searching) was sufficient to sustain their response. Thus food restriction in broiler breeders is a welfare concern. However these methods could be used to test alternative feeding regimes to attempt to find ways of alleviating hunger while still maintaining healthy growth and reproduction in these birds

  1. Contaminated Larval and Adult Lesser Mealworms, Alphitobius diaperinus (Coleoptera: Tenebrionidae)can Transmit Salmonella Typhimurium in a Broiler Flock

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The ability of the lesser mealworm, Alphitobius diaperinus (Panzer), commonly known as the darkling beetle, to transmit a marker strain Salmonella Typhimurium to day-of-hatch broiler chicks was evaluated, as well as the spread to non-challenged pen mates. Day-of-hatch chicks were orally gavaged wit...

  2. Contaminated larval and adult darkling beetles can serve as vectors in transmission of Salmonella Typhimurium in a broiler flock

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding the role darkling beetles serve in Salmonella transmission is critical in order to develop better food pathogen intervention strategies on the broiler farm. Prior studies have shown that Salmonella can persist in darkling beetles (Alphitobius diaperinus) up to 63 d, more than long eno...

  3. Estimation of the prevalence of Salmonella species on the slatted area compared to the scratch area of broiler breeder chicken houses.

    PubMed

    Behnke, Elena L; Hofacre, Charles L; Berghaus, Roy D

    2013-09-01

    With the objective of detecting Salmonella species in the poultry house environment, sampling broiler breeder houses in the two-thirds slatted area and the one-third scratch area with pine shavings bedding can be difficult. The slatted area is where the females, consisting of approximately 90% of the population, eat, drink, and spend the majority of their time. The scratch area is where the males eat and drink, as well as where mating and mortality occur. Besides the nest boxes, the female feeders and water lines make the slatted areas more difficult to sample. However, it is important to take samples from the area with the greatest likelihood of isolating Salmonella. Therefore, boot swab samples were collected from 21 commercial broiler breeder chicken houses representing three different companies in north Georgia to estimate the prevalence of Salmonella on the slat vs. the scratch area in each chicken house. Every house sampled had a central scratch area covered with litter and two elevated slat areas constructed of wood. Four boot swab samples were collected on each side slat area by walking the entire length of the house for each swab. Eight samples were collected in the same manner from the scratch area. Results of 335 total samples were acquired, 167 of which were obtained from the slat area and 168 of which came from the scratch area, yielding 242 total Salmonella isolations. Salmonella was found in 117 of the slat samples, representing 70.1%, compared to 125 of the scratch area samples, representing 74.4%. Both the univariate (P = 0.311) and the multivariable (P = 0.303) analysis showed that sampling location was not associated with Salmonella prevalence.

  4. Constant and changing photoperiods in the laying period for broiler breeders allowed [corrected] normal or accelerated growth during the rearing period.

    PubMed

    Lewis, P D; Gous, R M

    2006-02-01

    Broiler breeder pullets were grown on 8-h photoperiods to 2.23 or 2.42 kg of BW at 20 wk, and then transferred abruptly to 11- or 16-h photoperiods. Subsequently, some of the 11-h photoperiod birds were given 15-min increases in day length weekly or a 1-h increase every 4 wk to reach 16 h of light at 54 wk. The birds transferred abruptly to a 16-h photoperiod at 20 wk matured 4 d earlier than 11-h photoperiod birds, required 500 g less feed to reach 50% lay, but, because of a 3% lower rate of lay after peak, produced 5 fewer eggs to 60 wk. However, the number of settable eggs was similar for the 2 groups because the 11-h photoperiod birds laid more eggs on the floor, resulting in more cracked and dirty eggs. The 11-h photoperiod birds converted feed into egg more efficiently, and were 100 g heavier at end of lay. Increasing the photoperiod in 15-min or 1-h increments from 11 to 16 h during the laying cycle depressed egg production. Mean egg weight and mortality were similar for all lighting groups. The heavier BW birds at 20 wk reached maturity 1 d earlier, but used 1 kg more feed to reach maturity, laid 5 fewer total eggs (because of a 3% lower rate of lay after peak), produced 7 more unsettable eggs (because more eggs were laid on the floor), and converted feed into egg less efficiently than did the lighter BW birds. Mean egg weight, BW at 57 wk, and mortality were similar for both groups. There was no significant light x growth interaction for any performance parameter. It is concluded that there is no benefit to egg production from extending the photoperiod to 16 h when broiler breeders are kept in light-proofed housing, especially if they have access to illuminated nest boxes.

  5. Effect of trypsin inhibitor activity in soya bean on growth performance, protein digestibility and incidence of sub-clinical necrotic enteritis in broiler chicken flocks.

    PubMed

    Palliyeguru, M W C D; Rose, S P; Mackenzie, A M

    2011-06-01

    1. The effect of three different levels of dietary trypsin inhibitor activity (achieved by varying the amount of non-toasted full fat soya bean in replacement for toasted full fat soya bean) on the incidence of spontaneously-occurring sub-clinical necrotic enteritis (NE) in broiler chickens was compared. A fourth dietary treatment compared the effect of a diet that used potato protein concentrate as the major protein source. The determined trypsin inhibitor activity increased with the increasing content of non-toasted soya bean: 1·90, 6·21, 8·46 and 3·72 mg/g for the three soya bean diets (0, 100 and 200 g of non-toasted soya bean/kg) and the potato protein diet respectively. 2. Although increasing amounts of the non-toasted full-fat soya bean increased the feed intakes of the birds, there was a marked reduction in protein digestibility, weight gain and feed conversion efficiency. 3. There was a linear increase in sub-clinical NE lesions in the duodenum, jejunum, mid small intestine and ileum with increasing non-toasted soya bean. Caecal Clostridium perfringens counts increased with the increasing dietary content of non-toasted soya bean. Serum α-toxin antibodies were higher in the birds fed the 200 g non-toasted soya bean/kg diet compared with the other diets. 4. The results demonstrated that variation in the amount of non-toasted dietary soya bean not only affects growth performance of broilers but also affects the incidence of sub-clinical necrotic enteritis in the flock. Ensuring the lowest possible trypsin-inhibitor activity in soya bean samples is a valuable tool to improve the health and welfare of birds and in reducing the financial losses from this disease.

  6. Effect of feeder space during the growing and laying periods and the rate of feed increase at the onset of lay on broiler breeder female reproductive function.

    PubMed

    Leksrisompong, N; Romero-Sanchez, H; Oviedo-Rondón, E O; Brake, J

    2014-07-01

    A study was conducted to examine how 2 feeder space allocations during the rearing period followed by 2 feeder space allocations after photostimulation and 2 female feeding to peak programs (fast or slow) affected female broiler breeder reproductive performance and mortality. Sixteen pens of 76 breeder females each were equipped with either 4 tube feeders with a 132 cm circumference pan (7.0 cm/female) or 6 feeders (10.4 cm/female) to 21 wk of age. Thereafter, 64 females were moved to breeding pens, photostimulated, and fed sex-separate from either 3 (6.2 cm/female) or 5 (10.3 cm/female) feeders with either fast or slow feeding to peak feeding programs applied to complete a 2 × 2 × 2 factorial design. Seven males that were separately reared in a similar manner were added per pen. Individual female BW was determined at 6, 20, and 32 wk of age and BW uniformity assessed. Greater feeder space during rearing increased BW at 32 wk of age, whereas greater feeder space during lay or slow feeding to peak decreased BW at 32 wk. There were no differences in BW uniformity. Hens from the 10.4 to 10.3 cm/female combination produced a significantly greater number of eggs as compared with the 7.0 to 10.3 cm/female and 10.4 to 6.2 cm/female combinations with the 7.0 to 6.2 cm/female combination intermediate. Percentage hen-day egg production of the 10.4 to 10.3 cm/female combination hens was significantly greater than all other combinations. Livability was improved in the 10.4 to 10.3 cm/female combination relative to the 7.0 to 10.3 cm/female combination with the others intermediate. The fast feeding to peak program increased yolk weight as well as yolk:albumen ratio at 28 and 30 wk of age, but egg weight did not differ. These data indicated that increased or decreased feeder space between the growing and laying periods did not affect broiler breeder female BW, uniformity, egg weight, fertility, or hatchability. The 10.3 cm/female laying feeder space exhibited the best hen

  7. Prevalence, molecular characterization and antimicrobial resistance of Salmonella serovars isolated from northwestern Spanish broiler flocks (2011-2015).

    PubMed

    Lamas, A; Fernandez-No, I C; Miranda, J M; Vázquez, B; Cepeda, A; Franco, C M

    2016-09-01

    The present study investigated the prevalence, antimicrobial resistance to twenty antibiotics, and class 1 integron and virulence genes of Salmonella isolated from poultry houses of broilers in northwestern Spain between 2011 and 2015. Strains were classified to the serotype level using the Kauffman-White typing scheme and subtyping with enterobacterial repetitive intergenic consensus PCR. The prevalence of Salmonella spp. was 1.02%. Sixteen different serotypes were found, with S. typhimurium and S. arizonae 48:z4, z23:- being the most prevalent. A total of 59.70% of strains were resistant to at least one, and 19.70% were resistant to multiple drugs. All Salmonella spp. were susceptible to cefotaxime, ciprofloxacin, gentamicin, kanamycin, levofloxacin, neomycin, and trimethoprim. The highest level of resistance was to sulfamethoxazole (40.29%), doxycycline (17.91%), and nalidixic acid (17.91%). None of the isolates carried class 1 integron and only isolates of S. enterica subspecies enterica were positive for all virulence factors tested, whereas S. arizonae lacked genes related to replication and invasion in nonphagocytic cells. This study demonstrates that the prevalence and antimicrobial resistance of Salmonella spp. in poultry houses of broilers of northwestern Spain is low compared with those found in other studies and in other steps of the food chain.

  8. Detection of Campylobacter bacteria in air samples for continuous real-time monitoring of Campylobacter colonization in broiler flocks.

    PubMed

    Olsen, Katja N; Lund, Marianne; Skov, Julia; Christensen, Laurids S; Hoorfar, Jeffrey

    2009-04-01

    Improved monitoring tools are important for the control of Campylobacter bacteria in broiler production. In this study, we compare the sensitivities of detection of Campylobacter by PCR with feces, dust, and air samples during the lifetimes of broilers in two poultry houses and conclude that the sensitivity of detection of Campylobacter in air is comparable to that in other sample materials. Profiling of airborne particles in six poultry houses revealed that the aerodynamic conditions were dependent on the age of the chickens and very comparable among different poultry houses, with low proportions of particles in the 0.5- to 2-microm-diameter range and high proportions in the 2- to 5-microm-diameter range. Campylobacter could also be detected by PCR in air samples collected at the hanging stage during the slaughter process but not at the other stages tested at the slaughterhouse. The exploitation of airborne dust in poultry houses as a sample material for the detection of Campylobacter and other pathogens provides an intriguing possibility, in conjunction with new detection technologies, for allowing continuous or semicontinuous monitoring of colonization status.

  9. Campylobacter epidemiology from breeders to their progeny in Eastern Spain.

    PubMed

    Ingresa-Capaccioni, S; Jiménez-Trigos, E; Marco-Jiménez, F; Catalá, P; Vega, S; Marin, C

    2016-03-01

    While horizontal transmission is a route clearly linked to the spread of Campylobacter at the farm level, few studies support the transmission of Campylobacter spp. from breeder flocks to their offspring. Thus, the present study was carried out to investigate the possibility of vertical transmission. Breeders were monitored from the time of housing day-old chicks, then throughout the laying period (0 to 60 wk) and throughout their progeny (broiler fattening, 1 to 42 d) until slaughter. All samples were analyzed according with official method ISO 10272:2006. Results revealed that on breeder farms, Campylobacter isolation started from wk 16 and reached its peak at wk 26, with 57.0% and 93.2% of positive birds, respectively. After this point, the rate of positive birds decreased slightly to 86.0% at 60 wk. However, in broiler production all day-old chicks were found negative for Campylobacter spp, and the bacteria was first isolated at d 14 of age (5.0%), with a significant increase in detection during the fattening period with 62% of Campylobacter positive animals at the end of the production cycle. Moreover, non-positive sample was determined from environmental sources. These results could be explained because Campylobacter may be in a low concentration or in a non-culturable form, as there were several studies that successfully detected Campylobacter DNA, but failed to culture. This form can survive in the environment and infect successive flocks; consequently, further studies are needed to develop more modern, practical, cost-effective and suitable techniques for routine diagnosis. PMID:26628341

  10. Campylobacter epidemiology from breeders to their progeny in Eastern Spain.

    PubMed

    Ingresa-Capaccioni, S; Jiménez-Trigos, E; Marco-Jiménez, F; Catalá, P; Vega, S; Marin, C

    2016-03-01

    While horizontal transmission is a route clearly linked to the spread of Campylobacter at the farm level, few studies support the transmission of Campylobacter spp. from breeder flocks to their offspring. Thus, the present study was carried out to investigate the possibility of vertical transmission. Breeders were monitored from the time of housing day-old chicks, then throughout the laying period (0 to 60 wk) and throughout their progeny (broiler fattening, 1 to 42 d) until slaughter. All samples were analyzed according with official method ISO 10272:2006. Results revealed that on breeder farms, Campylobacter isolation started from wk 16 and reached its peak at wk 26, with 57.0% and 93.2% of positive birds, respectively. After this point, the rate of positive birds decreased slightly to 86.0% at 60 wk. However, in broiler production all day-old chicks were found negative for Campylobacter spp, and the bacteria was first isolated at d 14 of age (5.0%), with a significant increase in detection during the fattening period with 62% of Campylobacter positive animals at the end of the production cycle. Moreover, non-positive sample was determined from environmental sources. These results could be explained because Campylobacter may be in a low concentration or in a non-culturable form, as there were several studies that successfully detected Campylobacter DNA, but failed to culture. This form can survive in the environment and infect successive flocks; consequently, further studies are needed to develop more modern, practical, cost-effective and suitable techniques for routine diagnosis.

  11. A comparison of the effects of feeding treatments and lighting on age at first egg and subsequent laying performance and carcase composition of broiler breeder hens.

    PubMed

    Ciacciariello, M; Gous, R M

    2005-04-01

    The effects of the growth curve from 15 to 20 weeks, age at photostimulation and pattern of photostimulus on sexual maturity, egg production and egg weight were evaluated in two trials with broiler breeder females to 56 and 34 weeks of age (housed in litter pens and individually caged, respectively). Carcase composition and reproductive morphology of hens varying in laying efficiency were measured in the second trial. Trial 1: Four growth curves were applied from 15 to 20 weeks to pullets housed in litter pens. Birds were transferred from 8- to 10-h photoperiods at 20 or 24 weeks of age, followed by weekly increments of one hour to reach a 16-h final photoperiod. Lower-than-recommended body weights at 20 weeks significantly delayed sexual maturity, reduced peak rate of lay, total eggs and mean egg weight. However, double-yolked egg production was lower, resulting in non-significant differences in settable egg numbers between body weight treatments. Birds reared to the heaviest body weight exhibited a significantly advanced sexual maturity, but total egg numbers, peak rate of lay and mean egg weight were not significantly affected. However, the laying of more double-yolked eggs resulted in a decrease in the number of settable eggs. Delaying photostimulation to 24 weeks significantly retarded sexual maturity, reduced total and settable egg numbers, and increased mean egg weight. A tendency for fewer double-yolked eggs was observed. Trial 2: At 19 weeks, birds were selected from the 4 body weight categories in Trial 1 and moved to individual cages in 8 rooms. Five lighting programmes were applied. The pattern of photostimulation applied did not affect any of the production traits measured. At 34 weeks, 24 birds were selected for the analysis of reproductive morphology, presence of internal or multiple ovulations, and carcase composition. Eight hens showing an early age at first egg and regular egg production records, 8 birds showing erratic laying performance and 8

  12. Effect of dietary manganese on antioxidant status and expression levels of heat-shock proteins and factors in tissues of laying broiler breeders under normal and high environmental temperatures.

    PubMed

    Zhu, Yong-Wen; Lu, Lin; Li, Wen-Xiang; Zhang, Li-Yang; Ji, Cheng; Lin, Xi; Liu, Hsiao-Ching; Odle, Jack; Luo, Xu-Gang

    2015-12-28

    To investigate the effect of Mn on antioxidant status and expression levels of heat-shock proteins/factors in tissues of laying broiler breeders subjected to heat challenge, we used a completely randomised design (n 6) with a factorial arrangement of 2 environmental temperatures (normal, 21 (sem 1)°C and high, 32 (sem 1)°C)×3 dietary Mn treatments (an Mn-unsupplemented basal diet (CON), or a basal diet supplemented with 120 mg Mn/kg diet as inorganic Mn sulphate (iMn) or organic Mn proteinate (oMn)). There were no interactions (P>0·10) between environmental temperature and dietary Mn in all of the measured indices. High temperature decreased (P<0·003) Mn content, and also tended (P=0·07) to decrease copper zinc superoxide dismutase (CuZnSOD) activity in the liver and heart. However, an increased manganese superoxide dismutase (MnSOD) activity (P<0·05) and a slight increase of malondialdehyde level (P=0·06) were detected in breast muscle. Up-regulated (P<0·05) expression levels of heat-shock factor 1 (HSF1) and HSF3 mRNA and heat-shock protein 70 (HSP70) mRNA and protein were found in all three tissues. Broiler breeders fed either iMn or oMn had higher tissue Mn content (P<0·0001), heart MnSOD and CuZnSOD activities (P<0·01) and breast muscle MnSOD protein levels (P<0·05), and lower (P<0·05) breast muscle HSP70 mRNA and protein levels than those fed CON. Broiler breeders fed oMn had higher (P<0·03) bone Mn content than those fed iMn. These results indicate that high temperature decreases Mn retention and increases HSP70 and HSF1, HSF3 expression levels in tissues of laying broiler breeders. Furthermore, dietary supplementation with Mn in either source may enhance heart antioxidant ability and inhibit the expression of HSP70 in breast muscle. Finally, the organic Mn appears to be more available than inorganic Mn for bone in laying broiler breeders regardless of environmental temperatures.

  13. Effect of an electrostatic space charge system on airborne dust and subsequent potential transmission of microorganisms to broiler breeder pullets by airborne dust.

    PubMed

    Richardson, L J; Mitchell, B W; Wilson, J L; Hofacre, C L

    2003-01-01

    High levels of dust and microorganisms are known to be associated with animal confinement rearing facilities. Many of the microorganisms are carried by dust particles, thus providing an excellent vector for horizontal disease transmission between birds. Two environmentally controlled rooms containing female broiler breeder pullets (n = 300) were used to evaluate the effectiveness of an electrostatic space charge system (ESCS) in reducing airborne dust and gram-negative bacteria levels over an 8-wk period (starting when the birds were 10 wk old). The ESCS was used to evaluate the effectiveness of reducing airborne microorganism levels by charging airborne dust particles and causing the particles to be attracted to grounded surfaces (i.e., walls, floor, equipment). The use of the ESCS resulted in a 64% mean reduction in gram-negative bacteria. Airborne dust levels were reduced an average of 37% over a 1-wk period in the experimental room compared with the control room on the basis of samples taken every 10 min. The reductions of airborne dust and bacteria in this study are comparable with earlier results obtained with the ESCS in commercial hatching cabinets and experimental caged layer rooms, suggesting the system could also be applied to other types of enclosed animal housing. PMID:12713167

  14. Illuminance and UV-A exposure during rearing affects egg production in broiler breeders transferred to open-sided adult housing.

    PubMed

    Lewis, P D; Ghebremariam, W; Gous, R M

    2007-08-01

    1. Broiler breeders were reared in light-proof accommodation on 8-h photoperiods at an illuminance of 10 (W10), 40 (W40) or 100 lux (W100) from warm-white fluorescent lamps, or 10 lux (UV10) from Arcadia bird lamps (white light plus UV-A emission). At 20 weeks, 200 birds from each group were transferred to open-sided housing and a 16-h mixture of natural and warm-white fluorescent light. 2. Mortality during rearing and body weight at 20 weeks were similar for all groups. 3. The W10 birds matured 2 d later, had inferior rates of lay over peak production and laid 9 fewer eggs to 60 weeks than the other groups. Mean egg weight, extra large egg production and mortality between 20 and 60 weeks were unaffected by lighting during the rearing period. The UV10 birds had a significantly better rate of lay between 52 and 60 weeks than any of the groups reared on white light. 4. The findings suggest that ultraviolet radiation does not directly affect hypothalamic activity, but that retinally received UV during the rearing period prolongs the laying cycle through a modification of the hormonal control of photorefractoriness.

  15. Effects of growth patterns and dietary crude protein levels during rearing on body composition and performance in broiler breeder females during the rearing and laying period.

    PubMed

    van Emous, R A; Kwakkel, R P; van Krimpen, M M; Hendriks, W H

    2013-08-01

    The combined effects of growth pattern (GP) and dietary CP level during rearing (2 to 22 wk of age) on body composition and performance were investigated in broiler breeder females from 0 to 40 wk of age. One-day-old pullets (n = 768) were randomly allotted to 48 pens according to 2 growth patterns (standard = SGP and high = HGP) and fed using 1 of 3 dietary CP levels (high = CPh, medium = CPm, and low = CPl). From 19 to 22 wk of age, feeding level was gradually adjusted to obtain a similar target BW for all birds, and then until 40 wk of age, all birds received similar amounts of a standard breeder diet. During the rearing period, the HGP pullets were fed a higher feed intake level (6.5%) than SGP pullets. To meet BW targets at 22 wk of age, feed intake from d 14 onward had to be increased for the CPm (4.6%) and CPl (10.0%) treatments. Breast muscle percentages of HGP and SGP pullets were similar at any age, although abdominal fat pad at 20 wk was 0.18% higher for HGP pullets. Pullets fed the CPl diet had a lower breast muscle percentage compared with pullets fed the CPm and CPh diets (0.46 and 0.85% at wk 10, 0.81 and 1.45% at wk 20, respectively). Abdominal fat pads in CPl pullets were 0.18 and 0.22% (wk 10), and 0.24 and 0.42% (wk 20) higher compared with CPm and CPh pullets, respectively. At 40 wk of age, no effects on breast muscle and abdominal fat pad were found among all treatments. Egg production, sexual maturation, and egg weight were not affected by GP and CP levels during rearing. It was concluded that a low CP diet during rearing decreased breast muscle and increased abdominal fat pad, whereas a high GP only increased abdominal fat pad, at the end of the rearing period. Decreasing dietary CP level seems to be more effective in increasing abdominal fat pad than increasing GP.

  16. Circadian variation in heart rate, blood pressure, body temperature and EEG of immature broiler breeder chickens in restricted-fed and ad libitum-fed states.

    PubMed

    Savory, C J; Kostal, L; Nevison, I M

    2006-10-01

    1. Heart rate, intra-aortic blood pressure, deep body temperature and telencephalic EEG were monitored by radiotelemetry in 6 freely moving immature broiler breeders (three in each of two years), during routine food restriction and then ad libitum feeding, over two 24-h periods in each feeding state.2. Heart rate, blood pressure and body temperature were all higher during ad libitum than restricted feeding, and heart rate and body temperature were higher by day (12 h) than at night (12 h). The decreases in heart rate and body temperature at night were greater during restricted than ad libitum feeding. Blood pressure tended to be higher at night, except in year 2 during restricted feeding. Body temperature and ambient temperature were higher in year 2 than year 1.3. During restricted feeding, marked peaks in heart rate, blood pressure and body temperature in the 15 min after provision of the daily food ration at 09:00 h, when birds were eating, were equivalent to corresponding values seen during ad libitum feeding.4. Relative powers in delta (1 to 4 Hz) and theta (4 to 8 Hz) frequency bands of the EEG power spectrum were higher at night in year 2 only, while power in the alpha (8 to 12 Hz) band was higher at night in both years.5. It is concluded that most of the variation in heart rate, blood pressure and body temperature between feeding states and times of day/night can be accounted for in terms of variation in food intake and energy expenditure. The greater slow wave (delta, theta) EEG activity seen after lights-off in year 2 may reflect non-paradoxical sleep at that time.

  17. Development of the Intestinal RNA Virus Community of Healthy Broiler Chickens.

    PubMed

    Shah, Jigna D; Desai, Prerak T; Zhang, Ying; Scharber, Sarah K; Baller, Joshua; Xing, Zheng S; Cardona, Carol J

    2016-01-01

    Several RNA viruses such as astrovirus, rotavirus, reovirus and parvovirus have been detected in both healthy and diseased commercial poultry flocks. The aim of this study was to characterize (a) the development of the RNA viral community in the small intestines of healthy broiler chickens from hatch through 6 weeks of age (market age) and (b) the contribution of the breeder source vs. bird age in development of the community structure. Intestinal tissue samples were harvested from breeders and their progeny, processed for viral RNA extraction and sequenced using Illumina Hiseq sequencing technology resulting in 100 bp PE reads. The results from this study indicated that the breeder source influenced the RNA viral community only at hatch but later environment i.e. bird age had the more significant effect. The most abundant RNA viral family detected at 2, 4 and 6 weeks of age was Astroviridae, which decreased in abundance with age while the abundance of Picornaviridae increased with age.

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

    PubMed

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

    2016-05-01

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

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

    PubMed

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

    2016-05-01

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

  20. Comparative differences in the composition and biomechanical properties of tibiae of seven- and seventy-two-week-old male and female broiler breeder chickens.

    PubMed

    Rath, N C; Balog, J M; Huff, W E; Huff, G R; Kulkarni, G B; Tierce, J F

    1999-08-01

    Skeletal problems are common in both young and old poultry and are often related to bone weakness. They affect mortality on the farm and condemnations within processing plant and thus raise both welfare and economic concerns. To understand the basis of bone strength, the metaphyseal histology, composition, and the biomechanical properties of tibiae from 7- and 72-wk-old male and female broiler breeder chickens were compared. The biochemical constituents included ash, collagen, proteoglycan, transforming growth factor-beta (TGF-beta), pyridinium crosslinks, and the organic matrix-associated fluorescence. Blood variables were measured to determine the metabolic status of these birds as related to bone physiology. Although there were no differences in blood chemistry of 7-wk-old males and females, there were several differences between young and old birds. The levels of calcium, triglyceride, and iron were higher in older females than in older males. The collagen content was reduced, and the proteoglycan content increased in 72-wk-old hens. The TGF-beta content of bones from 7-wk-old females was higher than that of other groups of birds. Bone strength and stiffness, measured using loads at break and Young's modulus, respectively, were higher in older birds. The presence of medullary bones in 72-wk-old hens did not affect their bone strength, although it reduced strain values and increased Young's modulus. Compared to other groups, the 72-wk-old hens had a higher content of an inorganic matrix. The levels of hydroxylysylpyridinoline (HP) and lysylpyridinoline (LP) and the collagenase-extractable fluorescence of the organic matrix from older birds was higher. The decalcified bone matrix from older birds also showed higher susceptibility to bacterial collagenase than their younger counterparts. Bone strength showed positive correlations with its ash content, density, pyridinium crosslinks, and the fluorescence of the matrix. However, the correlation was strong with both

  1. Yolk sac nutrient composition and fat uptake in late-term embryos in eggs from young and old broiler breeder hens.

    PubMed

    Yadgary, L; Cahaner, A; Kedar, O; Uni, Z

    2010-11-01

    In the present study, we examined the composition, amount, and uptake of yolk nutrients [fat, protein, water, and carbohydrates (COH)] during incubation of eggs from 30- and 50-wk-old broiler breeder hens. Eggs were sampled at embryonic d 0 (fresh eggs), 13, 15, 17, 19, and 21 (hatch). Egg, embryo, yolk content, and yolk sac membrane were weighed, and the yolk sac (YS; i.e., yolk content + yolk sac membrane) composition was analyzed. From 30 to 50 wk of age, the albumen weight increased by 13.3%, whereas the yolk increased by more than 40%. The proportion of fat in the fresh yolk of the 30-wk-old group was 23.8% compared with 27.4% in the 50-wk-old group, whereas the proportion of protein was 17.9% compared with 15.6%, respectively. During incubation, results indicated that water and protein infiltrated from other egg compartments to the YS. Accordingly, the calculated change in the content of water and protein between fresh yolk and sampled YS does not represent the true uptake of these components from the YS to the embryo, and only fat uptake from the YS can be accurately estimated. By embryonic d 15, fat uptake relative to embryo weight was lower in the 30-wk-old group than in the 50-wk-old group. However, by embryonic d 21, embryos of both groups reached similar relative fat uptake, suggesting that to hatch, embryos must attain a certain amount of fat as a source of energy for the hatching process. The amount of COH in the YS increased similarly during incubation in eggs from hens of both ages, reaching a peak at embryonic d 19, suggesting COH synthesis in the YS. At hatch, the amount of protein, water, and COH in the residual YS, relative to the weight of the yolk-free chick, was similar in eggs from young and old hens. However, chicks from the younger hens had less fat in the YS for their immediate posthatch nutrition compared with those from the older hens.

  2. Reproductive performance and oviductal expression of avidin and avidin-related protein-2 in young and old broiler breeder hens orally exposed to supplementary biotin.

    PubMed

    Daryabari, H; Akhlaghi, A; Zamiri, M J; Mianji, G Rahimi; Pirsaraei, Z Ansari; Deldar, H; Eghbalian, A N

    2014-09-01

    Published data on the probable involvement of avidin and avidin-related protein-2 (AVR2) in sustaining sperm viability in sperm storage tubules in 38-wk-old turkeys, and the high affinity of avidin or its analogs to biotin suggest that supplementary biotin may increase oviductal avidin and AVR2 expression, thereby attenuating the adverse effect of aging on hen reproductive performance. Broiler breeder hens (n = 120) were randomly assigned to receive 0 (T0), 0.30 (T1), or 0.45 (T2) mg of biotin/L of drinking water from 30 to 33 (young) and 53 to 56 (old) wk of age, and artificially inseminated to determine their reproductive performance. At the end of each period of biotin administration, 8 hens from each treatment group were killed for RNA extraction from the uterovaginal junction. Egg production was lower in the old hens (44%) compared with the young ones (82%), and biotin supplementation increased egg production only in the latter. Administering supplementary biotin to young hens increased their oviductal expression of AVR2, which was much higher in the old hens (1.0 and 4.6 for young and old groups, respectively). Fertility rate was not different between young and old hens, and was increased (4.4%) at the higher level of biotin supplementation. Hatchability and hatchling quality were not affected by biotin supplementation. Embryonic mortality between 17 to 21 d of incubation was higher in young (5.2%) compared with old (1.4%) birds. Egg fertility rate showed a moderate correlation (P < 0.05) with avidin (r = 0.59) and AVR2 (r = 0.55) expression in the young-age group, and very low correlations in old-age group (0.04 and 0.17). Regardless of the hen's age, the correlation coefficient of hatchability with avidin or AVR2 expression was very low (-0.16 and 0.18). Overall, the effect of biotin supplementation on AVR2 expression, and the relationship between biotin administration and oviductal expression of avidin and AVR2 was dependent on the hen's age, being higher

  3. Reproductive efficiency and metabolism of female broiler breeders as affected by genotype, feed allocation, and age at photostimulation. 1. Pullet growth and development.

    PubMed

    Robinson, F E; Zuidhof, M J; Renema, R A

    2007-10-01

    A 3 x 4 x 2 factorial design was carried out to determine the effect of 3 broiler breeder strains, 4 target BW profiles, and 2 photostimulation ages on pullet growth and development. A total of 560 pullets from each strain (Hubbard Hi-Y, Ross 508, and Ross 708) were reared on BW profiles that separated at 4 wk and converged at 32 wk of age as follows: standard (mean target BW profile of the 3 strains used), low (12-wk BW target = 25% lower than standard followed by rapid gain to 32 wk), moderate (12-wk BW target = 150% of standard followed by lower rate of gain to 32 wk), and high (12-wk BW target = 200% of standard followed by minimal growth to 32 wk). Birds were photostimulated at 18 (18WK) or 22 wk (22WK). During the prephotostimulation phase (2 to 18 wk of age), 4 birds were killed for each of the 12 interactions at 14-d intervals to characterize changes in carcass traits. After 18 wk (wk 20, 22, and 24), 4 birds from each of the 24 interactions were killed and dissected (n = 768). Growth rate restricted frame size (e.g., 18-wk shank length: low = 101.8; standard = 105.6; moderate = 109.5; and high = 112.3 mm). At 24 wk of age, the 22WK birds had similar amounts of breast muscle compared with 18WK birds, whereas the later photostimulated hens had heavier abdominal fat pads. Early photo-stimulation resulted in increased 24-wk liver weights in all strains, but the difference was greatest in Ross 708 birds. The 22-wk ovary weight was influenced by age at photostimulation in high (18WK = 17.3; 22WK = 1.6 g) and moderate (18WK = 14.1; 22WK = 1.1 g) birds. The more extensive feed restriction of LOW birds before 12 wk of age appeared to limit breast muscle and fat pad growth and slow reproductive tract development following photostimulation. Pullets on heavier BW profiles respond to early PS by developing the reproductive system at the expense of breast muscle and fat pad growth. Genetic strain modulates some of the effect of very different target BW profiles.

  4. Comparisons of Sperm Storage Tubule Distribution and Number in Four Strains of Mature Broiler Breeders and in Turkey Hens Before and After the Onset of Photostimulation

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The biological basis of sustained fertility in broiler and turkey hens is their capacity to store sperm in the oviductal sperm storage tubules (SSTs) located in the uterovaginal junction. The objectives of this study were to determine if the numbers of SST varied between four strains of broiler bre...

  5. Construction of an infectious cDNA clone of genotype 1 avian hepatitis E virus: characterization of its pathogenicity in broiler breeders and demonstration of its utility in studying the role of the hypervariable region in virus replication.

    PubMed

    Park, Soo-Jeong; Lee, Byung-Woo; Moon, Hyun-Woo; Sung, Haan Woo; Yoon, Byung-Il; Meng, Xiang-Jin; Kwon, Hyuk Moo

    2015-05-01

    A full-length infectious cDNA clone of the genotype 1 Korean avian hepatitis E virus (avian HEV) (pT11-aHEV-K) was constructed and its infectivity and pathogenicity were investigated in leghorn male hepatoma (LMH) chicken cells and broiler breeders. We demonstrated that capped RNA transcripts from the pT11-aHEV-K clone were translation competent when transfected into LMH cells and infectious when injected intrahepatically into the livers of chickens. Gross and microscopic pathological lesions underpinned the avian HEV infection and helped characterize its pathogenicity in broiler breeder chickens. The avian HEV genome contains a hypervariable region (HVR) in ORF1. To demonstrate the utility of the avian HEV infectious clone, several mutants with various deletions in and beyond the known HVR were derived from the pT11-aHEV-K clone. The HVR-deletion mutants were replication competent in LMH cells, although the deletion mutants extending beyond the known HVR were non-viable. By using the pT11-aHEV-K infectious clone as the backbone, an avian HEV luciferase reporter replicon and HVR-deletion mutant replicons were also generated. The luciferase assay results of the reporter replicon and its mutants support the data obtained from the infectious clone and its derived mutants. To further determine the effect of HVR deletion on virus replication, the capped RNA transcripts from the wild-type pT11-aHEV-K clone and its mutants were injected intrahepatically into chickens. The HVR-deletion mutants that were translation competent in LMH cells displayed in chickens an attenuation phenotype of avian HEV infectivity, suggesting that the avian HEV HVR is important in modulating the virus infectivity and pathogenicity.

  6. Construction of an infectious cDNA clone of genotype 1 avian hepatitis E virus: characterization of its pathogenicity in broiler breeders and demonstration of its utility in studying the role of the hypervariable region in virus replication.

    PubMed

    Park, Soo-Jeong; Lee, Byung-Woo; Moon, Hyun-Woo; Sung, Haan Woo; Yoon, Byung-Il; Meng, Xiang-Jin; Kwon, Hyuk Moo

    2015-05-01

    A full-length infectious cDNA clone of the genotype 1 Korean avian hepatitis E virus (avian HEV) (pT11-aHEV-K) was constructed and its infectivity and pathogenicity were investigated in leghorn male hepatoma (LMH) chicken cells and broiler breeders. We demonstrated that capped RNA transcripts from the pT11-aHEV-K clone were translation competent when transfected into LMH cells and infectious when injected intrahepatically into the livers of chickens. Gross and microscopic pathological lesions underpinned the avian HEV infection and helped characterize its pathogenicity in broiler breeder chickens. The avian HEV genome contains a hypervariable region (HVR) in ORF1. To demonstrate the utility of the avian HEV infectious clone, several mutants with various deletions in and beyond the known HVR were derived from the pT11-aHEV-K clone. The HVR-deletion mutants were replication competent in LMH cells, although the deletion mutants extending beyond the known HVR were non-viable. By using the pT11-aHEV-K infectious clone as the backbone, an avian HEV luciferase reporter replicon and HVR-deletion mutant replicons were also generated. The luciferase assay results of the reporter replicon and its mutants support the data obtained from the infectious clone and its derived mutants. To further determine the effect of HVR deletion on virus replication, the capped RNA transcripts from the wild-type pT11-aHEV-K clone and its mutants were injected intrahepatically into chickens. The HVR-deletion mutants that were translation competent in LMH cells displayed in chickens an attenuation phenotype of avian HEV infectivity, suggesting that the avian HEV HVR is important in modulating the virus infectivity and pathogenicity. PMID:25593160

  7. Effects of breeder age and egg weight on morphological changes in the small intestine of chicks during the hatch window.

    PubMed

    Yalçin, S; Izzetoğlu, G T; Aktaş, A

    2013-01-01

    1. The objective of the study was to investigate the effects of breeder age and egg weight on hatching performance and morphological changes in segments of the small intestine of broiler chicks during a 21 h hatch window. 2. Eggs from Ross broiler breeder flocks aged 29 (young) and 48 weeks (old) were classified as light (LE) or heavy (HE) and incubated at the same conditions. At 475 h of incubation, eggs were checked every 3 h to determine time of external pipping and hatching. The first 42 chicks to emerge from each group were weighed and chick length was measured and 14 chicks from each group were sampled to collect residual yolk and intestine segments. The rest of chicks were placed back in the incubator and chick weight and length were measured individually at 9, 15 and 21 h after chicks hatched. At the end of 21 h, 14 chicks from each group were sampled again and the same procedure was followed. 3. The HE chicks pipped and hatched later than LE, regardless of breeder age. From hatch to the end of the hatch window, chick weight, but not yolk-free chick weight, gradually reduced. Relative residual yolk weight of chicks from both egg weights was similar at hatch, however, yolk sac utilisation was higher for LE chicks during the 21 h post-hatch period. At hatch, jejunum and ileum villus development was very similar for HE and LE chicks but greater development was observed for villus area with an increase in the jejunum villus length, width and goblet cell numbers in HE chicks. 4. The longest jejunum villus and the widest duodenum and jejunum villus were obtained for HE chicks from old breeders indicating that HE chicks from old breeders would have a greater surface area for nutrient absorption.

  8. Comparison of sample types and analytical methods for the detection of highly campylobacter-colonized broiler flocks at different stages in the poultry meat production chain.

    PubMed

    Seliwiorstow, Tomasz; Duarte, Alexandra; Baré, Julie; Botteldoorn, Nadine; Dierick, Katelijne; Uyttendaele, Mieke; De Zutter, Lieven

    2015-05-01

    Exclusion of broiler batches, highly colonized with Campylobacter (>7.5 log10 colony-forming units/g), from the fresh poultry meat market might decrease the risk of human campylobacteriosis. The objective of this study was to compare different sample types (both at the farm and the slaughterhouse) and methods (direct culture, quantitative real-time polymerase chain reaction [qPCR], propidium monoazide [PMA]-qPCR) applied for the quantification of the Campylobacter colonization level. In addition, the applicability of the lateral flow-based immunoassay, Singlepath(®) Direct Campy Poultry test (Singlepath(®) test), was evaluated as a rapid method for the qualitative detection of Campylobacter in highly colonized broiler batches. Campylobacter counts differed significantly between sample types collected at farm level (cecal droppings, feces, boot swabs) and at slaughterhouse level (cecal content, fecal material from crates). Furthermore, comparison of Campylobacter counts obtained by different methods (direct culture, qPCR, PMA-qPCR) in cecal droppings revealed significant differences, although this was not observed for cecal-content samples. Evaluation of the Singlepath(®) test on cecal droppings and cecal-content samples revealed an acceptable level of sensitivity and specificity. In conclusion, cecal droppings and cecal content are proposed as the most representative sample types for quantification of Campylobacter colonization level of broilers at farm and slaughterhouse, respectively. Direct culture and qPCR are equally sensitive for quantification of Campylobacter in fresh cecal-content samples. PMA treatment before qPCR inhibits the signal from dead Campylobacter cells. Consequently, when samples are extensively stored and/or transported, qPCR is preferred to direct culture and PMA-qPCR. Furthermore, the Singlepath(®) test offers a convenient alternative method for rapid detection of Campylobacter in highly colonized broiler batches.

  9. Unexpected consequences of genetic selection in broilers and turkeys: problems and solutions.

    PubMed

    Hocking, P M

    2014-02-01

    1. Genetic theory leads to the expectation that unexpected consequences of genetic selection for production traits will inevitably occur and that these changes are likely to be undesirable. 2. Both artificial selection for production efficiency and "natural" selection for adaptation to the production environment result in selection sweeps that increase the frequencies of rare recessive alleles that have a negative effect on fitness. 3. Fitness is broadly defined as any trait that affects the ability to survive, reproduce and contribute to the next generation, such as musculoskeletal disease in growing broiler chickens and multiple ovulation in adult broiler parents. 4. Welfare concerns about the negative effects of genetic selection on bird welfare are sometimes exaggerated but are nevertheless real. Breeders have paid increasing attention to these traits over several decades and have demonstrated improvement in pedigree flocks. There is an urgent need to monitor changes in commercial flocks to ensure that genetic change is accompanied by improvements in that target population. 5. New technologies for trait measurement, whole genome selection and targeted genetic modification hold out the promise of efficient and rapid improvement of welfare traits in future breeding of broiler chickens and turkeys. The potential of targeted genetic modification for enhancing welfare traits is considerable, but the goal of achieving public acceptability for the progeny of transgenic poultry will be politically challenging.

  10. Differences in egg nutrient availability, development, and nutrient metabolism of broiler and layer embryos.

    PubMed

    Nangsuay, A; Molenaar, R; Meijerhof, R; van den Anker, I; Heetkamp, M J W; Kemp, B; van den Brand, H

    2015-03-01

    Selection for production traits of broilers and layers leads to physiological differences, which may already be present during incubation. This study aimed to investigate the influence of strain (broiler vs layer) on egg nutrient availability, embryonic development and nutrient metabolism. A total of 480 eggs with an egg weight range of 62.0 to 64.0 g from Lohmann Brown Lite and Ross 308 breeder flocks of 41 or 42 weeks of age were selected in two batches of 120 eggs per batch per strain. For each batch, 30 eggs per strain were used to determine egg composition, including nutrient and energy content, and 90 eggs per strain were separately incubated in one of two climate respiration chambers at an eggshell temperature of 37.8°C. The results showed that broiler eggs had a higher ratio of yolk: albumen with 2.41 g more yolk and 1.48 g less albumen than layers. The yolk energy content of broiler eggs was 46.32 kJ higher than that of layer eggs, whereas total energy content of broiler eggs was 47.85 kJ higher compared to layer eggs. Yolk-free body mass at incubation day 16 and chick weight and length at hatch were higher in broilers compared to layers. Respiration quotient of broiler embryos was higher than layer embryos during incubation day 8 to incubation day 10. A 0.24 g lower residual yolk at the hatch of broiler embryos than for the layer embryos indicated that broiler embryos used more yolk and had a higher energy utilization and energy deposition in yolk-free body mass. Heat production of broiler embryos was higher than that of layer embryos from incubation day 12 to incubation day 18, but efficiency of converting egg energy used by embryos to form yolk-free body mass was similar. In conclusion, broiler and layer embryos have different embryonic development patterns, which affect energy utilization and embryonic heat production. However, the embryos are equal in efficiency of converting the energy used to yolk-free body mass.

  11. Effect of feeder space during the growing and laying periods and the rate of feed increase at the onset of lay on broiler breeder female reproductive function1 2

    PubMed Central

    Leksrisompong, N.; Romero-Sanchez, H.; Oviedo-Rondón, E. O.; Brake, J.

    2014-01-01

    A study was conducted to examine how 2 feeder space allocations during the rearing period followed by 2 feeder space allocations after photostimulation and 2 female feeding to peak programs (fast or slow) affected female broiler breeder reproductive performance and mortality. Sixteen pens of 76 breeder females each were equipped with either 4 tube feeders with a 132 cm circumference pan (7.0 cm/female) or 6 feeders (10.4 cm/female) to 21 wk of age. Thereafter, 64 females were moved to breeding pens, photostimulated, and fed sex-separate from either 3 (6.2 cm/female) or 5 (10.3 cm/female) feeders with either fast or slow feeding to peak feeding programs applied to complete a 2 × 2 × 2 factorial design. Seven males that were separately reared in a similar manner were added per pen. Individual female BW was determined at 6, 20, and 32 wk of age and BW uniformity assessed. Greater feeder space during rearing increased BW at 32 wk of age, whereas greater feeder space during lay or slow feeding to peak decreased BW at 32 wk. There were no differences in BW uniformity. Hens from the 10.4 to 10.3 cm/female combination produced a significantly greater number of eggs as compared with the 7.0 to 10.3 cm/female and 10.4 to 6.2 cm/female combinations with the 7.0 to 6.2 cm/female combination intermediate. Percentage hen-day egg production of the 10.4 to 10.3 cm/female combination hens was significantly greater than all other combinations. Livability was improved in the 10.4 to 10.3 cm/female combination relative to the 7.0 to 10.3 cm/female combination with the others intermediate. The fast feeding to peak program increased yolk weight as well as yolk:albumen ratio at 28 and 30 wk of age, but egg weight did not differ. These data indicated that increased or decreased feeder space between the growing and laying periods did not affect broiler breeder female BW, uniformity, egg weight, fertility, or hatchability. The 10.3 cm/female laying feeder space exhibited the best hen

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

    PubMed

    Heuer, O E; Pedersen, K; Jensen, L B; Madsen, M; Olsen, J E

    2002-01-01

    The glycopeptide growth promoter avoparcin was banned from animal production in the EU in 1997 due to concern for the spread of vancomycin-resistant enterococci (VRE) from food animals to humans. In recent Norwegian and Danish studies, extensive occurrence of VRE on broiler farms and in broiler flocks after the avoparcin ban has been reported. The present study was undertaken to investigate the epidemiology of VRE on broiler farms in the absence of the selective pressure exerted by avoparcin. Environmental samples were obtained from five broiler houses after depopulation, cleaning, and disinfection of the houses between rotations, and two consecutive broiler flocks from each house were sampled by taking cloacal swabs from the broilers at the time of slaughter. A total of 69 vancomycin-resistant Enterococcus faecium isolates obtained from broiler flocks and broiler houses were subjected to molecular typing by pulsed-field gel electrophoresis (PFGE). Forty-one PFGE-profiles were observed. VRE with indistinguishable or highly similar PFGE profiles were isolated from consecutive broiler flocks and from environmental samples from the houses in which the flocks were reared, whereas VRE-isolates from different broiler houses and from flocks reared in different houses appeared to be genetically unrelated. These findings indicated that VRE was transmitted between consecutive broiler flocks by clones of resistant bacteria surviving in the broiler houses despite cleaning and disinfection between rotations. Thus, the extensive occurrence of VRE in broiler flocks after the avoparcin ban may be explained by persistence of VRE in the broiler house environment. PMID:12523633

  13. Inclusion body hepatitis associated with an outbreak of fowl adenovirus type 2 and type 8b in broiler flocks in South Africa.

    PubMed

    Maartens, Louis H; Joubert, Hilda W; Aitchison, Henry; Venter, Estelle H

    2015-01-01

    Inclusion body hepatitis is an acute disease of chickens ascribed to viruses of the genus Aviadenovirus and referred to as fowl adenovirus (FAdV). There are 12 FAdV types (FAdV1to FAdV8a and FAdV8b to FAdV11), classified into five species based on their genotype (designated FAdVA to FAdVE). A total of 218 000 chickens, 2-29 days of age, were affected over a 1-year period, all testing positive by microscopy, virus isolation and confirmation with polymerase chain reaction (PCR). Affected birds were depressed, lost body weight,were weak and had watery droppings. Pathological changes observed during necropsy indicated consistent changes in the liver, characterised by hepatomegaly, cholestasis and hepatitis. Lesions were also discernible in the spleen, kidney and gizzard wall and were characterised by splenomegaly, pinpoint haemorrhages, nephritis with haemorrhage,visceral gout and serosal ecchymosis of the gizzard wall. Histopathological lesions were most consistently observed in the liver but could also be seen in renal and splenic tissue. Virus isolation was achieved in embryonated eggs and most embryos revealed multifocalto diffuse hepatic necrosis, with a mixed cellular infiltrate of macrophages and heterophils(necro-granulomas), even in the absence of macroscopic pathology. Virus isolation results were verified by histopathology and PCR on embryonic material and further characterised by nucleotide sequence analysis. Two infectious bursal disease virus isolates were also made from the Klerksdorp flock. Nucleotide sequence analysis of the L1 hexon loop of all the FAdV isolates indicated homology (99%) with prototype strains P7-A for FAdV-2, as well as for FAdV-8b.

  14. A Systematic Review Characterizing On-Farm Sources of Campylobacter spp. for Broiler Chickens

    PubMed Central

    Agunos, Agnes; Waddell, Lisa; Léger, David; Taboada, Eduardo

    2014-01-01

    Campylobacter and antimicrobial-resistant Campylobacter are frequently isolated from broiler chickens worldwide. In Canada, campylobacteriosis is the third leading cause of enteric disease and the regional emergence of ciprofloxacin-resistant Campylobacter in broiler chickens has raised a public health concern. This study aimed to identify, critically appraise, and synthesize literature on sources of Campylobacter in broilers at the farm level using systematic review methodology. Literature searches were conducted in January 2012 and included electronic searches in four bibliographic databases. Relevant studies in French or English (n = 95) conducted worldwide in any year and all study designs were included. Risk of Bias and GRADE criteria endorsed by the Cochrane collaboration was used to assess the internal validity of the study and overall confidence in the meta-analysis. The categories for on-farm sources were: broiler breeders/vertical transfer (number of studies = 32), animals (n = 57), humans (n = 26), environment (n = 54), and water (n = 63). Only three studies examined the antimicrobial resistance profiles of Campylobacter from these on-farm sources. Subgroups of data by source and outcome were analyzed using random effect meta-analysis. The highest risk for contaminating a new flock appears to be a contaminated barn environment due to insufficient cleaning and disinfection, insufficient downtime, and the presence of an adjacent broiler flock. Effective biosecurity enhancements from physical barriers to restricting human movement on the farm are recommended for consideration to enhance local on-farm food safety programs. Improved sampling procedures and standardized laboratory testing are needed for comparability across studies. Knowledge gaps that should be addressed include farm-level drug use and antimicrobial resistance information, further evaluation of the potential for vertical transfer, and improved genotyping methods to

  15. House-Level Risk Factors for the Occurrence of Campylobacter in Broilers in Iceland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction Horizontal transmission from the environment is thought to be an important source of Campylobacter to broilers. Our objective was to identify broiler house characteristics and house-level management practices associated with the colonization of broiler flocks with Campylobacter in Icel...

  16. Isolation of naturally occurring Campylobacter from the circulating blood of commercial market age broilers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Campylobacter spp., are present in organs and tissues of broiler chickens but the dissemination route is unclear. The aim of the current study was to determine Campylobacter prevalence within circulating blood of commercial broilers. Broilers were acquired from 19 flocks originating from three com...

  17. Effect of post-hatch transportation duration and parental age on broiler chicken quality, welfare, and productivity

    PubMed Central

    Jacobs, Leonie; Delezie, Evelyne; Duchateau, Luc; Goethals, Klara; Ampe, Bart; Lambrecht, Evelien; Gellynck, Xavier; Tuyttens, Frank A. M.

    2016-01-01

    Broiler chicks are transported to production sites within one to 2 d post-hatch. Possible effects of this transportation are poorly understood and could vary among chicks from breeder flocks of different ages. The aim of the present study was to investigate the effects of transportation duration and parental flock age on chick welfare, productivity, and quality. After hatch in a commercial hatchery, 1,620 mixed-sex chicks from 29-wk old (young) and 1,620 chicks from 60-wk old (old) breeders were subjected to transportation of 1.5 h or 11 h duration. After transportation, 2,800 chicks were divided among 100 pens, with each pen containing 28 chicks from one transportation crate (2 or 3 pens per crate). From the remaining chicks, on average 6 chicks (min 4, max 8) per crate (n = 228) were randomly selected and assessed for chick quality, weighed, and culled for yolk sac weighing (one d). Chicks that had not been assigned to pens or were not used for post-transportation measurements, were removed from the experiment (n = 212). Mortality, ADG, BW, and feed conversion (FC) of the experimental chicks were recorded until 41 d. Meat quality was measured for breast fillets (n = 47). No interaction effect of parental age and transportation duration was found for any variables. BW and yolk sac weight at one d were lower for chicks transported 11 h than 1.5 h and for chicks from young versus old breeders. The effect of parental flock age on BW persisted until slaughter. Additionally, parental age positively affected ADG until slaughter. Chick quality was lower in chicks from old versus young breeders. Chick quality and productivity were not affected by transportation duration. Mortality and meat quality were not affected by either parental age or transportation duration. To conclude, no long-term detrimental effects were found from long post-hatch transportation in chicks from young or old parent flocks. Based on these results, we suggest that 11 h post

  18. Effect of post-hatch transportation duration and parental age on broiler chicken quality, welfare, and productivity.

    PubMed

    Jacobs, Leonie; Delezie, Evelyne; Duchateau, Luc; Goethals, Klara; Ampe, Bart; Lambrecht, Evelien; Gellynck, Xavier; Tuyttens, Frank A M

    2016-09-01

    Broiler chicks are transported to production sites within one to 2 d post-hatch. Possible effects of this transportation are poorly understood and could vary among chicks from breeder flocks of different ages. The aim of the present study was to investigate the effects of transportation duration and parental flock age on chick welfare, productivity, and quality. After hatch in a commercial hatchery, 1,620 mixed-sex chicks from 29-wk old (young) and 1,620 chicks from 60-wk old (old) breeders were subjected to transportation of 1.5 h or 11 h duration. After transportation, 2,800 chicks were divided among 100 pens, with each pen containing 28 chicks from one transportation crate (2 or 3 pens per crate). From the remaining chicks, on average 6 chicks (min 4, max 8) per crate (n = 228) were randomly selected and assessed for chick quality, weighed, and culled for yolk sac weighing (one d). Chicks that had not been assigned to pens or were not used for post-transportation measurements, were removed from the experiment (n = 212). Mortality, ADG, BW, and feed conversion ( FC: ) of the experimental chicks were recorded until 41 d. Meat quality was measured for breast fillets (n = 47). No interaction effect of parental age and transportation duration was found for any variables. BW and yolk sac weight at one d were lower for chicks transported 11 h than 1.5 h and for chicks from young versus old breeders. The effect of parental flock age on BW persisted until slaughter. Additionally, parental age positively affected ADG until slaughter. Chick quality was lower in chicks from old versus young breeders. Chick quality and productivity were not affected by transportation duration. Mortality and meat quality were not affected by either parental age or transportation duration. To conclude, no long-term detrimental effects were found from long post-hatch transportation in chicks from young or old parent flocks. Based on these results, we suggest that 11 h post

  19. Foodborne disease prevention and broiler chickens with reduced Campylobacter infection.

    PubMed

    Bahrndorff, Simon; Rangstrup-Christensen, Lena; Nordentoft, Steen; Hald, Birthe

    2013-03-01

    Studies have suggested that flies play a linking role in the epidemiology of Campylobacter spp. in broiler chickens and that fly screens can reduce the prevalence of Campylobacter spp. We examined the year-round and long-term effects of fly screens in 10 broiler chicken houses (99 flocks) in Denmark. Prevalence of Campylobacter spp.-positive flocks was significantly reduced, from 41.4% during 2003-2005 (before fly screens) to 10.3% in 2006-2009 (with fly screens). In fly screen houses, Campylobacter spp. prevalence did not peak during the summer. Nationally, prevalence of Campylobacter spp.-positive flocks in Denmark could have been reduced by an estimated 77% during summer had fly screens been part of biosecurity practices. These results imply that fly screens might help reduce prevalence of campylobacteriosis among humans, which is closely linked to Campylobacter spp. prevalence among broiler chicken flocks. PMID:23628089

  20. Foodborne disease prevention and broiler chickens with reduced Campylobacter infection.

    PubMed

    Bahrndorff, Simon; Rangstrup-Christensen, Lena; Nordentoft, Steen; Hald, Birthe

    2013-03-01

    Studies have suggested that flies play a linking role in the epidemiology of Campylobacter spp. in broiler chickens and that fly screens can reduce the prevalence of Campylobacter spp. We examined the year-round and long-term effects of fly screens in 10 broiler chicken houses (99 flocks) in Denmark. Prevalence of Campylobacter spp.-positive flocks was significantly reduced, from 41.4% during 2003-2005 (before fly screens) to 10.3% in 2006-2009 (with fly screens). In fly screen houses, Campylobacter spp. prevalence did not peak during the summer. Nationally, prevalence of Campylobacter spp.-positive flocks in Denmark could have been reduced by an estimated 77% during summer had fly screens been part of biosecurity practices. These results imply that fly screens might help reduce prevalence of campylobacteriosis among humans, which is closely linked to Campylobacter spp. prevalence among broiler chicken flocks.

  1. Serotyping of Salmonella Isolates from Broiler Vertical Integrations in Colombia

    Technology Transfer Automated Retrieval System (TEKTRAN)

    This study analyzed 106 Salmonella isolates from different points in broiler vertical integrations of two important poultry areas of Colombia. It was possible to identify the presence of Salmonella in five categories: breeder farm (17.9%), hatchery (6.6 %), broiler farm (38.7 %), processing plant (9...

  2. Salmonella in Broiler Litter and Properties of Soil at Farm Location

    PubMed Central

    Volkova, Victoriya V.; Bailey, R. Hartford; Wills, Robert W.

    2009-01-01

    Contamination of litter in a broiler grow-out house with Salmonella prior to placement of a new flock has been shown to be a precursor of the flock's Salmonella contamination further down the production continuum. In the southern USA, broiler grow-out houses are primarily built on dirt pad foundations that are placed directly on top of the native soil surface. Broiler litter is placed directly on the dirt pad. Multiple grow-out flocks are reared on a single litter batch, and the litter is kept in the houses during downtime between flocks. The effects of environmental determinants on conditions in broiler litter, hence Salmonella ecology within it, has received limited attention. In a field study that included broiler farms in the states of Alabama, Mississippi and Texas we assessed Salmonella in broiler litter at the end of downtime between flocks, i.e. at the time of placement of a new flock for rearing. Here we utilized these results and the U.S. General Soil Map (STATSGO) data to test if properties of soil at farm location impacted the probability of Salmonella detection in the litter. The significance of soil properties as risk factors was tested in multilevel regression models after accounting for possible confounding differences among the farms, the participating broiler complexes and companies, and the farms' geographical positioning. Significant associations were observed between infiltration and drainage capabilities of soil at farm location and probability of Salmonella detection in the litter. PMID:19636431

  3. Hydrodynamics of Turning Flocks.

    PubMed

    Yang, Xingbo; Marchetti, M Cristina

    2015-12-18

    We present a hydrodynamic model of flocking that generalizes the familiar Toner-Tu equations to incorporate turning inertia of well-polarized flocks. The continuum equations controlled by only two dimensionless parameters, orientational inertia and alignment strength, are derived by coarse-graining the inertial spin model recently proposed by Cavagna et al. The interplay between orientational inertia and bend elasticity of the flock yields anisotropic spin waves that mediate the propagation of turning information throughout the flock. The coupling between spin-current density to the local vorticity field through a nonlinear friction gives rise to a hydrodynamic mode with angular-dependent propagation speed at long wavelengths. This mode becomes unstable as a result of the growth of bend and splay deformations augmented by the spin wave, signaling the transition to complex spatiotemporal patterns of continuously turning and swirling flocks.

  4. Hydrodynamics of Turning Flocks.

    PubMed

    Yang, Xingbo; Marchetti, M Cristina

    2015-12-18

    We present a hydrodynamic model of flocking that generalizes the familiar Toner-Tu equations to incorporate turning inertia of well-polarized flocks. The continuum equations controlled by only two dimensionless parameters, orientational inertia and alignment strength, are derived by coarse-graining the inertial spin model recently proposed by Cavagna et al. The interplay between orientational inertia and bend elasticity of the flock yields anisotropic spin waves that mediate the propagation of turning information throughout the flock. The coupling between spin-current density to the local vorticity field through a nonlinear friction gives rise to a hydrodynamic mode with angular-dependent propagation speed at long wavelengths. This mode becomes unstable as a result of the growth of bend and splay deformations augmented by the spin wave, signaling the transition to complex spatiotemporal patterns of continuously turning and swirling flocks. PMID:26722945

  5. Coated ceramic breeder materials

    DOEpatents

    Tam, Shiu-Wing; Johnson, Carl E.

    1987-04-07

    A breeder material for use in a breeder blanket of a nuclear reactor is disclosed. The breeder material comprises a core material of lithium containing ceramic particles which has been coated with a neutron multiplier such as Be or BeO, which coating has a higher thermal conductivity than the core material.

  6. Coated ceramic breeder materials

    DOEpatents

    Tam, Shiu-Wing; Johnson, Carl E.

    1987-01-01

    A breeder material for use in a breeder blanket of a nuclear reactor is disclosed. The breeder material comprises a core material of lithium containing ceramic particles which has been coated with a neutron multiplier such as Be or BeO, which coating has a higher thermal conductivity than the core material.

  7. [Reoccurrence of histomonosis in turkey breeder farm].

    PubMed

    Aka, Johannes; Hauck, Rüdiger; Blankenstein, Petra; Balczulat, Stefanie; Hafez, Hafez Mohamed

    2011-01-01

    Histomonosis is a severe disease caused by the protozoan parasite Histomonas (H.) meleagridis, which can lead to high losses in turkeys. The present report describes the reoccurrence of histomonosis in a turkey breeder farm. The first outbreak occurred in 2005 in 17 weeks old hens, the second in 2009 in 8 weeks old hens. The disease remained restricted in one house and one compartment, respectively. Mortality rose to 26 and 65% respectively within few days in spite of therapy with various compounds. Both flocks had to be euthanized. In both cases H. meleagridis belonging to genotype A was detected. The source of infection remained unclear in both cases. PMID:21309161

  8. Breeder Reprocessing Engineering Test

    SciTech Connect

    Burgess, C.A.; Meacham, S.A.

    1984-01-01

    The Breeder Reprocessing Engineering Test (BRET) is a developmental activity of the US Department of Energy to demonstrate breeder fuel reprocessing technology while closing the fuel cycle for the Fast Flux Test Facility (FFTF). It will be installed in the existing Fuels and Materials Examination Facility (FMEF) at the Hanford Site near Richland, Washington, The major objectives of BRET are: (1) close the US breeder fuel cycle; (2) develop and demonstrate reprocessing technology and systems for breeder fuel; (3) provide an integrated test of breeder reactor fuel cycle technology - rprocessing, safeguards, and waste management. BRET is a joint effort between the Westinghouse Hanford Company and Oak Ridge National Laboratory. 3 references, 2 figures.

  9. A single vaccination of commercial broilers does not reduce transmission of H5N1 highly pathogenic avian influenza

    PubMed Central

    2011-01-01

    Vaccination of chickens has become routine practice in Asian countries in which H5N1 highly pathogenic avian influenza (HPAI) is endemically present. This mainly applies to layer and breeder flocks, but broilers are usually left unvaccinated. Here we investigate whether vaccination is able to reduce HPAI H5N1 virus transmission among broiler chickens. Four sets of experiments were carried out, each consisting of 22 replicate trials containing a pair of birds. Experiments 1-3 were carried out with four-week-old birds that were unvaccinated, and vaccinated at day 1 or at day 10 of age. Experiment 4 was carried out with unvaccinated day-old broiler chicks. One chicken in each trial was inoculated with H5N1 HPAI virus. One chicken in each trial was inoculated with virus. The course of the infection chain was monitored by serological analysis, and by virus isolation performed on tracheal and cloacal swabs. The analyses were based on a stochastic SEIR model using a Bayesian inferential framework. When inoculation was carried out at the 28th day of life, transmission was efficient in unvaccinated birds, and in birds vaccinated at first or tenth day of life. In these experiments estimates of the latent period (~1.0 day), infectious period (~3.3 days), and transmission rate parameter (~1.4 per day) were similar, as were estimates of the reproduction number (~4) and generation interval (~1.4 day). Transmission was significantly less efficient in unvaccinated chickens when inoculation was carried out on the first day of life. These results show that vaccination of broiler chickens does not reduce transmission, and suggest that this may be due to the interference of maternal immunity. PMID:21635732

  10. A comparison survey of organic and conventional broiler chickens for infectious agents affecting health and food safety.

    PubMed

    Van Overbeke, I; Duchateau, L; De Zutter, L; Albers, G; Ducatelle, R

    2006-06-01

    The purpose of the present cross-sectional study was to evaluate the health status of organic broiler chickens and the contamination rate with Salmonella and Campylobacter in organic broiler production in Belgium. The broilers were screened for antibodies against routinely monitored poultry diseases at 1 day old and at slaughter. Fecal examination for the presence of worm eggs was done at slaughter. Bacteriological examination for the detection of Salmonella and Campylobacter was performed at day 1, week 2, week 4, week 7, week 10, and slaughter. Conventional broilers of the same poultry integration and reared in the same geographic area were also screened and served as reference. Serologic data indicated lower antibody titers against infectious bronchitis and Newcastle disease in organic flocks. No significant differences could be found in prevalence of Salmonella between organic and conventional broilers at slaughter. In contrast, Campylobacter infections at slaughter were significantly higher in organic flocks. Organic flocks most probably become infected with Campylobacter between week 7 and week 10. Worm eggs were found in neither the organic flocks nor the conventional flocks. In conclusion, there are indications that the respiratory health status is better in organic broilers but that organic flocks are more often infected with Campylobacter than are conventional flocks.

  11. Phylogeny and S1 Gene Variation of Infectious Bronchitis Virus Detected in Broilers and Layers in Turkey.

    PubMed

    Yilmaz, Huseyin; Altan, Eda; Cizmecigil, Utku Y; Gurel, Aydin; Ozturk, Gulay Yuzbasioglu; Bamac, Ozge Erdogan; Aydin, Ozge; Britton, Paul; Monne, Isabella; Cetinkaya, Burhan; Morgan, Kenton L; Faburay, Bonto; Richt, Juergen A; Turan, Nuri

    2016-09-01

    The avian coronavirus infectious bronchitis virus (AvCoV-IBV) is recognized as an important global pathogen because new variants are a continuous threat to the poultry industry worldwide. This study investigates the genetic origin and diversity of AvCoV-IBV by analysis of the S1 sequence derived from 49 broiler flocks and 14 layer flocks in different regions of Turkey. AvCoV-IBV RNA was detected in 41 (83.6%) broiler flocks and nine (64.2%) of the layer flocks by TaqMan real-time RT-PCR. In addition, AvCoV-IBV RNA was detected in the tracheas 27/30 (90%), lungs 31/49 (62.2%), caecal tonsils 7/22 (31.8%), and kidneys 4/49 (8.1%) of broiler flocks examined. Pathologic lesions, hemorrhages, and mononuclear infiltrations were predominantly observed in tracheas and to a lesser extent in the lungs and a few in kidneys. A phylogenetic tree based on partial S1 sequences of the detected AvCoV-IBVs (including isolates) revealed that 1) viruses detected in five broiler flocks were similar to the IBV vaccines Ma5, H120, M41; 2) viruses detected in 24 broiler flocks were similar to those previously reported from Turkey and to Israel variant-2 strains; 3) viruses detected in seven layer flocks were different from those found in any of the broiler flocks but similar to viruses previously reported from Iran, India, and China (similar to Israel variant-1 and 4/91 serotypes); and 4) that the AVCoV-IBV, Israeli variant-2 strain, found to be circulating in Turkey appears to be undergoing molecular evolution. In conclusion, genetically different AvCoV-IBV strains, including vaccine-like strains, based on their partial S1 sequence, are circulating in broiler and layer chicken flocks in Turkey and the Israeli variant-2 strain is undergoing evolution. PMID:27610718

  12. Temperature-Related Risk Factors for the Occurrence of Campylobacter in Broilers in Iceland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction A summertime increased risk of Campylobacter is well-established in humans and broilers. Our objective was to identify temperature-related risk factors for the colonization of broiler flocks with Campylobacter in Iceland, with an assumption that flies play a role in the epidemiology an...

  13. U.S. broiler housing ammonia emissions inventory

    NASA Astrophysics Data System (ADS)

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

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

  14. Development and validation of a drag swab method using tampons and different diluents for the detection of members of Salmonella in broiler houses.

    PubMed

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

    2011-12-01

    Members of the genus Salmonella represent a significant public health concern and also a colonizer of commercial poultry. Therefore, the early detection and management of colonized broiler breeders and their progeny is essential. There have been numerous methods for farm-based detection, with gauze-based drag swabs being the most commonly used. In the present study, the wet (boiled water, buffered peptone water and double-strength skin milk) tampon was compared with the gauze to determine the recovery rate (10(2) colony-forming units/swab) of five common poultry serovars of Salmonella and after cold (4°C/48 h) storage. The recovery was found to be equivalent when tested using the ISO6572:2002 method, for all diluents (Cohen's κ =1.0; sensitivity = 1.0; specificity = 1.0). The subsequent field trial (n = 15 farms) compared the tampon drag swab (TDS) with a statistically appropriate (90% confidence, detect 10% prevalence) number of faecal swabs (n = 22), which also showed high agreement between the TDS and faecal sampling (κ = 0.86; McNemar's χ(2) = 1.0; sensitivity = 0.9; specificity = 1.0). However, direct faecal sampling showed a wider diversity of serovars of Salmonella than the corresponding TDS. The TDS is a very sensitive, readily available and cost-effective screening method for salmonellas in broiler breeder houses. This TDS technique may be used for routinely screening of broiler houses, and faecal sampling would only be used to confirm colonization or contamination, and to measure flock serovar variance.

  15. Detection of Campylobacter in 100 commercial flocks - evaluation of plating media and filtration method

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Campylobacter is a natural member of the gut microflora in many commercial broilers and as such can become a contaminant on edible surfaces during processing. Culturing gut contents or feces can be a means to determine flock status prior to live-haul. The wide variety of non-Campylobacter backgrou...

  16. Flocking in Flow

    NASA Astrophysics Data System (ADS)

    Ouellette, Nicholas; Khurana, Nidhi

    2013-03-01

    Models of active, self-propelled particles with simple interaction rules have long been shown to produce large-scale emergent behavior reminiscent of collective animal motion seen in nature. Such model flocks can be shown to be robust against random noise terms added to the equations. But real animals, such as birds, fish, or insects, live in fluid environments, where the background flow field is nonzero and is often turbulent. In this case, the fluctuations experienced by the individuals in the aggregation are not random, but rather are correlated in space and time. We explore the impact of such spatiotemporally correlated perturbations on flocking by numerically simulating the behavior of a simple flocking model in a turbulent-like flow field produced by a kinematic simulation. The introduction of flow strongly changes the flock formation dynamics. Additionally, we find that under some conditions the background flow tends to break stable flocks into smaller units. We study these clusters, and discuss their relation to the underlying flow field.

  17. Bacterial chondronecrosis with osteomyelitis in broilers: influence of sires and straight-run versus sex-separate rearing.

    PubMed

    Wideman, R F; Al-Rubaye, A; Reynolds, D; Yoho, D; Lester, H; Spencer, C; Hughes, J D; Pevzner, I Y

    2014-07-01

    Two experiments (E1, E2) were conducted to compare the influence of sires (sire A on dam C vs. sire B on dam C) and straight-run versus sex-separate rearing on the incidence of bacterial chondronecrosis with osteomyelitis (BCO) in broilers. Fertile eggs from commercial breeder flocks were incubated and hatched at the University of Arkansas Poultry Research Hatchery. Male and female chicks were reared together (straight-run) or separately (sex-separate) in 3 × 3 m pens on litter or flat wire flooring with 65 (E1) or 60 (E2) birds per pen. Necropsies revealed lesions that are pathognomonic for BCO in ≥98% of the birds that became lame. The SigmaStat Z-test was used to compare cumulative BCO incidences through 8 wk of age. For birds reared on litter, the incidences of BCO were low regardless of cross or sex (range: 1.7 to 5.1%; P ≥ 0.6). Within a cross and sex, rearing the broilers straight-run versus sex-separate on wire flooring did not significantly affect the incidence of BCO. Significant incidences of BCO did not develop until after d 40. Males from the sire A cross developed a higher incidence of BCO than males from the sire B cross in E1 (27 vs. 17%, respectively; P = 0.009) but not in E2 (28.5 vs. 22.6%, respectively; P = 0.141). In both experiments, males from the sire A cross developed higher incidences of BCO than females from the sire B cross (27 vs. 11.9%, in E1; 28.5 vs. 14.8%, in E2). With the sexes pooled, broilers from the sire A cross consistently developed higher incidences of BCO than broilers from the sire B cross (21.4 vs. 14.9%, P = 0.005 in E1; 26.5 vs. 18.7%, P = 0.003 in E2). High susceptibilities to both femoral head (all femoral head necrosis = 66 to 85% incidences) and tibial head (all tibial head necrosis = 81 to 96% incidences) BCO lesions were demonstrated in lame birds from both sexes and crosses. This study supports a sire influence on the susceptibility of broilers to BCO. Sire lines can be chosen to reduce BCO susceptibility

  18. Relations between the occurrence of resistance to antimicrobial growth promoters among Enterococcus faecium isolated from broilers and broiler meat.

    PubMed

    Emborg, H-D; Andersen, J S; Seyfarth, A M; Andersen, S R; Boel, J; Wegener, H C

    2003-08-01

    From 1995 to 2001, Enterococcus faecium isolates were collected from broiler flocks at slaughter and broiler meat products at retail outlets and were tested for susceptibility to classes of antimicrobials used for growth promotion in broilers in Denmark, namely: evernimicin, glycopeptide, macrolide and streptogramin. By February 1998, all antimicrobial growth promoters (AGPs) were withdrawn from the Danish broiler production. The present study investigates, by logistic regression analyses, the (1) changes in the occurrence of AGP resistance among E. faecium from broilers and broiler meat from the fourth quarter of 1995 to the fourth quarter of 2001 and (2) relations between the occurrence of AGP resistance among E. faecium isolates from Danish broilers and AGP resistance among E. faecium isolates from the broiler meat of Danish and unknown origin collected in the same quarter within the year. In the present study, we showed that after the AGP withdrawal, a significant decline in resistance to avilamycin, erythromycin, vancomycin and virginiamycin was observed among E. faecium from broilers and broiler meat. In addition, a decline in the occurrence of AGP resistance among E. faecium from Danish broilers was associated with a decrease in the predicted probability of isolating an AGP-resistant E. faecium isolate from a randomly selected broiler meat product. In the analyses "relations between the occurrence of AGP resistance among E. faecium isolated from broilers and broiler meat collected in the same quarter" errors in the explanatory variable were expected. Therefore, a simulation study was performed to validate the results from logistic regression analyses. The results obtained by the two methods were similar.

  19. Prevalence of Helicobacter pullorum in conventional, organic, and free-range broilers and typing of isolates.

    PubMed

    Manfreda, Gerardo; Parisi, Antonio; Lucchi, Alex; Zanoni, Renato Giulio; De Cesare, Alessandra

    2011-01-01

    Helicobacter pullorum represents a potential food-borne pathogen, and avian species appear to be a relevant reservoir of this organism. In this study, the prevalence of H. pullorum was investigated at 30 conventional farms where 169 ceca from 34 flocks were tested, at eight organic farms where 39 ceca from eight flocks were tested, and at seven free-range farms where 40 ceca from eight flocks were tested. All of the ceca were obtained from healthy broiler chickens. Moreover, amplified fragment length polymorphism, pulsed-field gel electrophoresis, and automated ribotyping were employed to estimate the levels of genetic variability of H. pullorum broiler isolates within and between flocks. Overall, Gram-negative, slender, curved rods, identified as H. pullorum by PCR, were isolated at 93.3% of the farms tested. The percentage of positive free-range farms (54.2%) was significantly lower than that of conventional (100%) or organic (100%) farms (P < 0.001). The level of within-flock genetic variability, calculated as the number of flocks colonized by isolates genetically different by all of the typing methods, was 34.9%. Isolates showing identical profiles by each typing method were observed in 11.6% of the flocks, but they were never detected between flocks. However, groups of isolates clustered together with an overall similarity level of ≥85%. Our results suggest that even though a high level of genetic variability is attributable to H. pullorum broiler isolates, their hierarchical genotyping produces data useful for epidemiological investigations.

  20. In-house Windrowing of a Commercial Broiler Farm During Summer Months and Its Effect on Litter Composition

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In-house windrowing of broiler litter between flocks has been suggested as an effective method to reduce pathogens and improve the quality of the house environment in which new chicks are placed. In this study, different methods of in-house windrowing were tested in commercial broiler houses during...

  1. Fast Breeder Reactor studies

    SciTech Connect

    Till, C.E.; Chang, Y.I.; Kittel, J.H.; Fauske, H.K.; Lineberry, M.J.; Stevenson, M.G.; Amundson, P.I.; Dance, K.D.

    1980-07-01

    This report is a compilation of Fast Breeder Reactor (FBR) resource documents prepared to provide the technical basis for the US contribution to the International Nuclear Fuel Cycle Evaluation. The eight separate parts deal with the alternative fast breeder reactor fuel cycles in terms of energy demand, resource base, technical potential and current status, safety, proliferation resistance, deployment, and nuclear safeguards. An Annex compares the cost of decommissioning light-water and fast breeder reactors. Separate abstracts are included for each of the parts.

  2. Ceramic breeder materials

    SciTech Connect

    Johnson, C.E.

    1990-01-01

    The breeding blanket is a key component of the fusion reactor because it directly involves tritium breeding and energy extraction, both of which are critical to development of fusion power. The lithium ceramics continue to show promise as candidate breeder materials. This promise was recognized by the International Thermonuclear Reactor (ITER) design team in its selection of ceramics as the first option for the ITER breeder material. Blanket design studies have indicated properties in the candidate materials data base that need further investigation. Current studies are focusing on tritium release behavior at high burnup, changes in thermophysical properties with burnup, compatibility between the ceramic breeder and beryllium multiplier, and phase changes with burnup. Laboratory and in-reactor tests, some as part of an international collaboration for development of ceramic breeder materials, are underway. 32 refs., 1 fig., 1 tab.

  3. Detection of avian nephritis virus in Australian chicken flocks.

    PubMed

    Hewson, Kylie A; O'Rourke, Denise; Noormohammadi, Amir H

    2010-09-01

    Avian nephritis virus (ANV) is thought to infect poultry flocks worldwide, but no confirmed case has been reported in Australia. The first such case is described in this study. Cases of young chickens with clinical signs of dehydration and diarrhea were submitted to our laboratory and histopathology detected interstitial nephritis. Vaccine strains of infectious bronchitis virus were detected in some of these cases but were not considered to be the causative agent. A total of seven fresh submissions from broiler chicken flocks were collected at 8-11 days of age. Degenerate PCR primers were designed based on published ANV polymerase gene sequences and used to analyze historic cases as well as the fresh submissions. Six of the seven fresh submissions, and one historic case, were positive for ANV with nucleotide sequencing confirming these results. These results establish ANV as an infectious pathogen circulating in Australian poultry.

  4. Flock-based microfluidics.

    PubMed

    Hitzbleck, Martina; Lovchik, Robert D; Delamarche, Emmanuel

    2013-05-21

    Flock-based microfluidics are created by depositing hydrophilic microfibers on an adhesive-coated substrate using an electric field. This enables the fabrication of self-powered microfluidics from one or more different kinds of fibers that form 2D and 3D flowpaths, which can wick 40 microliters of liquid per square centimeter. With this approach, large areas of functional wicking materials can be produced at extremely low cost.

  5. Measurement of broiler litter production rates and nutrient content using recycled litter.

    PubMed

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

    2006-03-01

    It is important for broiler producers to know litter production rates and litter nutrient content when developing nutrient management plans. Estimation of broiler litter production varies widely in the literature due to factors such as geographical region, type of housing, size of broiler produced, and number of flocks reared on the same litter. Published data for N, P, and K content are also highly variable. In addition, few data are available regarding the rate of production, characteristics, and nutrient content of caked litter (cake). In this study, 18 consecutive flocks of broilers were reared on the same litter in experimental pens under simulated commercial conditions. The mass of litter and cake produced was measured after each flock. Samples of all litter materials were analyzed for pH, moisture, N, P, and K. Average litter and cake moisture content were 26.4 and 46.9%, respectively. Significant variation in litter and cake nutrient content was observed and can largely be attributed to ambient temperature differences. Average litter, cake, and total litter (litter plus cake) production rates were 153.3, 74.8, and 228.2 g of dry litter material per kg of live broiler weight (g/kg) per flock, respectively. Significant variation in litter production rates among flocks was also observed. Cumulative litter, cake, and total litter production rates after 18 flocks were 170.3, 78.7, and 249.0 g/kg, respectively. The data produced from this research can be used by broiler producers to estimate broiler litter and cake production and the nutrient content of these materials.

  6. Enteric viruses detected by molecular methods in commercial chicken and turkey flocks in the United States between 2005 and 2006

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Intestinal samples collected from 43 commercial broiler, and 33 commercial turkey flocks from all regions of the United States during 2005 and 2006, were examined for the presence of astrovirus, rotavirus, reovirus, and coronavirus by RT-PCR, and for the presence of groups I and II adenovirus by PCR...

  7. A one-year study of campylobacter carriage by individual Danish broiler chickens as the basis for selection of Campylobacter spp. strains for a chicken infection model.

    PubMed Central

    Bang, D. D.; Nielsen, E. M.; Knudsen, K.; Madsen, M.

    2003-01-01

    From February 1999 to February 2000, 1,250 individual broiler chickens representing 125 broiler flocks originating from 62 broiler farms in Denmark were screened for campylobacter carriage. Every month, 10 flocks were tested for campylobacter carriage. The swabs were tested individually and as a pooled sample representing the flocks. Campylobacter spp. carriage was detected from 512 (40.9%) broiler chickens originating from 63 (50.4%) positive flocks. Campylobacter carriage by both individual chickens and flocks showed seasonal variation. Campylobacter jejuni was the dominant species (95.5%). Campylobacter isolates were typed using Penner heat-stable serotyping and flaA-typing methods. Data of campylobacter carriage by individual chickens and data generated by the use of different typing methods contributed to a better understanding of the dynamics of campylobacter infection within the broiler flocks. C. jejuni Penner heat-stable serotype HS2, flaA-type 1 was the most common type found in Danish broiler chickens. PMID:12729201

  8. The fusion breeder

    NASA Astrophysics Data System (ADS)

    Moir, Ralph W.

    1982-10-01

    The fusion breeder is a fusion reactor designed with special blankets to maximize the transmutation by 14 MeV neutrons of uranium-238 to plutonium or thorium to uranium-233 for use as a fuel for fission reactors. Breeding fissile fuels has not been a goal of the U.S. fusion energy program. This paper suggests it is time for a policy change to make the fusion breeder a goal of the U.S. fusion program and the U.S. nuclear energy program. There is wide agreement that many approaches will work and will produce fuel for five equal-sized LWRs, and some approach as many as 20 LWRs at electricity costs within 20% of those at today's price of uranium (30/lb of U3O8). The blankets designed to suppress fissioning, called symbiotes, fusion fuel factories, or just fusion breeders, will have safety characteristics more like pure fusion reactors and will support as many as 15 equal power LWRs. The blankets designed to maximize fast fission of fertile material will have safety characteristics more like fission reactors and will support 5 LWRs. This author strongly recommends development of the fission suppressed blanket type, a point of view not agreed upon by everyone. There is, however, wide agreement that, to meet the market price for uranium which would result in LWR electricity within 20% of today's cost with either blanket type, fusion components can cost severalfold more than would be allowed for pure fusion to meet the goal of making electricity alone at 20% over today's fission costs. Also widely agreed is that the critical-path-item for the fusion breeder is fusion development itself; however, development of fusion breeder specific items (blankets, fuel cycle) should be started now in order to have the fusion breeder by the time the rise in uranium prices forces other more costly choices.

  9. Coordinated Behaviour in Pigeon Flocks

    PubMed Central

    Yomosa, Makoto; Mizuguchi, Tsuyoshi; Vásárhelyi, Gábor; Nagy, Máté

    2015-01-01

    We analysed pigeon flock flights using GPS trajectory data to reveal the most important kinematic aspects of flocking behaviour. We quantitatively investigated the internal motion of the flock based on pairwise statistics and found the following general relationships in all datasets: i) the temporal order of decisions characterised by the delay between directional changes is strictly related to the spatial order characterised by the longitudinal relative position within the flock; ii) during circling motion, pigeons use a mixture of two idealised and fundamentally different turning strategies, namely, parallel-path and equal-radius type turning. While pigeons tend to maintain their relative position within the flock on average, as in the parallel-path approximation, those who turn later also get behind as in the equal-radius case. Equal-radius type turning also tends to be expressed more during smaller radius turns. PMID:26485662

  10. Coordinated Behaviour in Pigeon Flocks.

    PubMed

    Yomosa, Makoto; Mizuguchi, Tsuyoshi; Vásárhelyi, Gábor; Nagy, Máté

    2015-01-01

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

  11. Coordinated Behaviour in Pigeon Flocks.

    PubMed

    Yomosa, Makoto; Mizuguchi, Tsuyoshi; Vásárhelyi, Gábor; Nagy, Máté

    2015-01-01

    We analysed pigeon flock flights using GPS trajectory data to reveal the most important kinematic aspects of flocking behaviour. We quantitatively investigated the internal motion of the flock based on pairwise statistics and found the following general relationships in all datasets: i) the temporal order of decisions characterised by the delay between directional changes is strictly related to the spatial order characterised by the longitudinal relative position within the flock; ii) during circling motion, pigeons use a mixture of two idealised and fundamentally different turning strategies, namely, parallel-path and equal-radius type turning. While pigeons tend to maintain their relative position within the flock on average, as in the parallel-path approximation, those who turn later also get behind as in the equal-radius case. Equal-radius type turning also tends to be expressed more during smaller radius turns. PMID:26485662

  12. Campylobacter contamination and the relative risk of illness from organic broiler meat in comparison with conventional broiler meat.

    PubMed

    Rosenquist, Hanne; Boysen, Louise; Krogh, Anne Louise; Jensen, Annette Nygaard; Nauta, Maarten

    2013-04-01

    Danish organic broiler meat, represented by carcasses sampled at the end of processing after chilling, was more frequently contaminated with thermotolerant Campylobacter spp. than conventional broiler carcasses; the yearly mean prevalence being 54.2% (CI: 40.9-67.5) for organic and 19.7% (CI: 14.8-24.7) for conventional carcasses. Campylobacter jejuni was the most frequently isolated species. The difference in prevalence was obvious in all quarters of the year. Contamination of organic and conventional broiler carcasses was more likely to occur in the warmer summer months, in this case in the third quarter, as also documented for conventional broiler flocks. When contaminated, the mean concentration of Campylobacter on neck skin samples of organic and conventional carcasses was not significantly different (P=0.428); 2.0±0.65 log 10 cfu/g and 2.1±0.93 log 10 cfu/g, respectively. Assessing the relative risk of becoming ill following exposure to Campylobacter on conventional or organic broiler meat indicated that the risk per serving from organic carcasses was 1.7 times higher than that of conventional carcasses. The higher risk of illness from organic broiler carcasses compared with conventional broiler carcasses emphasizes the importance of implementing control measures in organic broiler production.

  13. An outbreak of blindness due to retinopathy in nine flocks of guinea fowl.

    PubMed

    Cecchinato, M; Lupini, C; Bolognesi, P G; Marzadori, F; Raffini, E; Frasnelli, M; Poppi, L; Shivaprasad, H L; Catelli, E

    2014-06-01

    Blindness was observed in 10- to 14-day-old guinea fowl. The incidence ranged from 25% to 80% in nine flocks within a total population of 110,000 guinea fowls. Clinical signs of blindness in birds included aimless wandering, failure to find feed and water, lateral recumbency, loss of weight, and increased mortality. The birds lacked papillary reflexes to light, and there were no gross lesions in the eyes. Histologically there was degeneration and disorganization of photoreceptors in the retina. The guinea fowl came from three different breeder sources but all of the birds were given the same feed. The condition was not observed in the subsequent flocks that came from the same breeder sources but that were given different feed. Based on these observations, toxicity of an unknown ingredient in the feed is suspected as the cause of blindness in the guinea fowl.

  14. Impact fragmentation of model flocks

    NASA Astrophysics Data System (ADS)

    Miller, Pearson W.; Ouellette, Nicholas T.

    2014-04-01

    Predicting the bulk material properties of active matter is challenging since these materials are far from equilibrium and standard statistical-mechanics approaches may fail. We report a computational study of the surface properties of a well known active matter system: aggregations of self-propelled particles that are coupled via an orientational interaction and that resemble bird flocks. By simulating the impact of these models flocks on an impermeable surface, we find that they fragment into subflocks with power-law mass distributions, similar to shattering brittle solids but not to splashing liquid drops. Thus, we find that despite the interparticle interactions, these model flocks do not possess an emergent surface tension.

  15. Prevalence and characterization of Salmonella species in entire steps of a single integrated broiler supply chain in Korea.

    PubMed

    Choi, Soo-Won; Ha, Jong-Su; Kim, Byoung-Yoon; Lee, Dong-Hun; Park, Jae-Keun; Youn, Ha-Na; Hong, Young-Ho; Lee, Sang-Bae; Lee, Joong-Bok; Park, Seung-Yong; Choi, In-Soo; Song, Chang-Seon

    2014-05-01

    The purpose of this study was to investigate the distribution of Salmonella species in an integrated broiler supply chain in Korea. A total of 1,214 samples from various steps of an integrated broiler production company including broiler breeder farms, broiler farms, broiler trucks, slaughterhouse, and retail chicken meats were collected and investigated. Salmonella was detected in 195 of the samples. The highest prevalence of Salmonella was observed in broiler transporting trucks (71.43%), followed by the slaughterhouse (63.89%) and broiler farms (16.05%). Salmonella Hadar was the most frequently isolated serotype (83.08%). All Salmonella Hadar isolates investigated in this study with pulsed-field gel electrophoresis showed the same XbaI pulsed-field gel electrophoresis pulsotype.

  16. Prevalence and characterization of Salmonella species in entire steps of a single integrated broiler supply chain in Korea.

    PubMed

    Choi, Soo-Won; Ha, Jong-Su; Kim, Byoung-Yoon; Lee, Dong-Hun; Park, Jae-Keun; Youn, Ha-Na; Hong, Young-Ho; Lee, Sang-Bae; Lee, Joong-Bok; Park, Seung-Yong; Choi, In-Soo; Song, Chang-Seon

    2014-05-01

    The purpose of this study was to investigate the distribution of Salmonella species in an integrated broiler supply chain in Korea. A total of 1,214 samples from various steps of an integrated broiler production company including broiler breeder farms, broiler farms, broiler trucks, slaughterhouse, and retail chicken meats were collected and investigated. Salmonella was detected in 195 of the samples. The highest prevalence of Salmonella was observed in broiler transporting trucks (71.43%), followed by the slaughterhouse (63.89%) and broiler farms (16.05%). Salmonella Hadar was the most frequently isolated serotype (83.08%). All Salmonella Hadar isolates investigated in this study with pulsed-field gel electrophoresis showed the same XbaI pulsed-field gel electrophoresis pulsotype. PMID:24795319

  17. Flocks, herds, and schools: A quantitative theory of flocking

    NASA Astrophysics Data System (ADS)

    Toner, John; Tu, Yuhai

    1998-10-01

    We present a quantitative continuum theory of ``flocking'': the collective coherent motion of large numbers of self-propelled organisms. In agreement with everyday experience, our model predicts the existence of an ``ordered phase'' of flocks, in which all members of even an arbitrarily large flock move together with the same mean velocity >≠0. This coherent motion of the flock is an example of spontaneously broken symmetry: no preferred direction for the motion is picked out a priori in the model; rather, each flock is allowed to, and does, spontaneously pick out some completely arbitrary direction to move in. By analyzing our model we can make detailed, quantitative predictions for the long-distance, long-time behavior of this ``broken symmetry state.'' The ``Goldstone modes'' associated with this ``spontaneously broken rotational symmetry'' are fluctuations in the direction of motion of a large part of the flock away from the mean direction of motion of the flock as a whole. These ``Goldstone modes'' mix with modes associated with conservation of bird number to produce propagating sound modes. These sound modes lead to enormous fluctuations of the density of the flock, far larger, at long wavelengths, than those in, e.g., an equilibrium gas. Our model is similar in many ways to the Navier-Stokes equations for a simple compressible fluid; in other ways, it resembles a relaxational time-dependent Ginsburg-Landau theory for an n=d component isotropic ferromagnet. In spatial dimensions d>4, the long-distance behavior is correctly described by a linearized theory, and is equivalent to that of an unusual but nonetheless equilibrium model for spin systems. For d<4, nonlinear fluctuation effects radically alter the long distance behavior, making it different from that of any known equilibrium model. In particular, we find that in d=2, where we can calculate the scaling exponents exactly, flocks exhibit a true, long-range ordered, spontaneously broken symmetry

  18. The effects of thermal manipulations during embryogenesis of broiler chicks on growth of embryo and skeletal traits

    NASA Astrophysics Data System (ADS)

    Aygün, Ali; Narinç, Doǧan

    2016-04-01

    Incubation temperature is one of the important environmental factors that can induce epigenetic thermal adaptation of different physiological control systems. Thus, post hatch thermo tolerance ability of birds may be gained using these manipulations during different incubation periods. The current study was carried out to reveal the effects of temperature manipulations during early and late embryogenesis on weight of embryo and size of skeletal bilateral traits (face, wings, metatarsus, tibia, and femur) in broiler chicken embryos. One thousand commercial broiler eggs from 46 week old breeder flock were used in study. Treatments consisted of eggs incubated at 37.8°C and 55% relative humidity throughout (control; DG1), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 0 to 8 (DG2), heated to 36.9°C and supplied 60% relative humidity for 6 hours daily from day 10 to 18 (DG3), heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 8 to 10 (DG4), and heated to 41°C and supplied 65% relative humidity for 3 hours daily from day 16 to 18 (DG5). Measurements of embryo weight and bilateral traits were obtained at 20 day of incubation and at hatch (at day 21). It was determined that the live weights of embryo and chick were affected significantly by treatment; DG3 group has shown higher mean values than the other treatment groups (P<0.05). There were differences in lengths of femur, tibia and metatarsus among treatment groups at hatch. Particularly, the high incubator temperatures at the second half of incubation accelerated growth of body and bone in embryos. These consequences of the treatments performed at different temperatures and times indicate that the different metabolic shifts realized by the embryos.

  19. Development and nutrient metabolism of embryos from two modern broiler strains.

    PubMed

    Nangsuay, A; Meijerhof, R; van den Anker, I; Heetkamp, M J W; Kemp, B; van den Brand, H

    2015-10-01

    A progressive selection for broiler live and processing performance traits has changed broiler growth patterns during the post hatch period. However, limited information is available to understand whether changes have also occurred during the embryonic stages. This study aims to examine influences of broiler strain on nutrient availability, embryonic development, and nutrient metabolism during incubation. Hatching eggs of Ross 308 and Cobb 500 fast feathering were selected from breeder flocks aged 43 to 46 weeks at an egg weight range of 60 to 63 g. Eggs were obtained in 2 batches, 120 eggs per strain per batch. For each batch, 20 eggs per strain were used to determine egg composition and nutrient availability. The remaining eggs were incubated separately in one of 2 climate respiration chambers at an eggshell temperature of 37.8°C. The results showed that Ross 308 eggs had a higher yolk:albumen ratio with 0.9 g more yolk and 0.7 g less albumen than Cobb 500. Albumen + yolk of Ross 308 eggs had a higher dry matter (Δ = 0.24 g) and crude fat (Δ = 0.23 g) than that of Cobb 500 eggs, but a similar amount of crude protein. Albumen and yolk of Ross 308 eggs had a higher energy content (Δ = 8.9 kJ) compared to Cobb 500 eggs. At 3 h after hatch, Ross 308 chicks were 0.2 cm longer and had a 0.6 g heavier yolk free body mass (YFBM) than Cobb 500 chicks. During incubation, Ross 308 embryos used 13.9 kJ more energy than Cobb 500, and the efficiency of converting energy used to YFBM (EYFB) was approximately 7.6% lower compared to Cobb 500. Ross 308 chicks hatched approximately 4 h later and had less hepatic glycogen (Δ = 5 mg) than Cobb 500 chicks. It can be concluded that, Cobb 500 and Ross 308 differ in egg nutrient availability and have different trajectories for embryonic development and nutrient metabolism during incubation.

  20. Hatching system and time effects on broiler physiology and posthatch growth.

    PubMed

    van de Ven, L J F; van Wagenberg, A V; Debonne, M; Decuypere, E; Kemp, B; van den Brand, H

    2011-06-01

    A multilevel housing system for broilers was developed, named Patio (Vencomatic BV, Eersel, the Netherlands), in which the hatching and brooding phase are combined. In a Patio system, climate conditions differ from those provided in the hatchers currently in use. We compared the physiology of broilers hatched in a hatcher or in a Patio system, and included the effects of hatching time. Eggs from 1 breeder flock were incubated until embryonic d 18 in a setter and subsequently placed in a hatcher or the Patio until the end of incubation. From each hatching system, 154 chicks were collected per hatching time, at 465 h (early), 480 h (midterm), and 493 h (late) of incubation, from which 24 chicks/group were decapitated for analyses of blood plasma and organ weights. The remaining 130 chicks in each group from both systems were individually labeled and placed together in the Patio system. All chicks were given access to feed and water directly after hatch and were housed up to d 45 to monitor growth. From embryonic d 18 until the end of incubation, average ambient temperature and RH were 38.1°C and 50.8% in the hatcher and 35.2°C and 29.7% in the Patio system. Glucose and corticosterone were slightly higher in hatcher chicks, whereas organ weights were not affected by the hatching system. Although hatchling weights were lower in hatchery chicks, growth from d 0 to 45 was not affected by the hatching system. In both systems, glucose increased with hatching time, whereas lactate and triiodothyronine levels decreased. Yolk weights decreased with hatching time, whereas absolute and relative weights of the yolk-free body, intestines, stomach, lungs, and heart increased, indicating more advanced maturation of organs. Growth up to d 21 was depressed in chicks in the late group, which was possibly related to lower thyroid hormone levels at hatching. We conclude that the hatching system had minor effects on hatchling physiology and that posthatch growth and livability were not

  1. Farm specific risk factors for Campylobacter colonisation in Danish and Norwegian broilers.

    PubMed

    Borck Høg, B; Sommer, H M; Larsen, L S; Sørensen, A I V; David, B; Hofshagen, M; Rosenquist, H

    2016-08-01

    Campylobacteriosis has become the leading bacterial zoonosis in humans in the European Union and other developed countries. There are many sources of human Campylobacter infections, but broilers and broiler meat have been shown to be the most important. In order to implement effective interventions that reduce the probability of Campylobacter colonisation of broiler flocks, it is essential to fully understand the risk factors involved. We present a bi-national risk factor survey comprising Campylobacter data from more than 5200 Danish and Norwegian indoor, conventional broiler flocks and the responses to a standardised questionnaire, with more than 40 explanatory variables from 277 Danish and Norwegian farms. We explored several models by using different combinations of the Danish and Norwegian data, including models with single-country datasets. All models were analysed using a generalized linear model using backwards elimination and forward selection. The results show that Norwegian broiler flocks had a lower risk of being colonised than Danish flocks. Farm specific variables that increased the risk of flocks becoming colonised with Campylobacter in both countries were: broiler houses older than five years; longer downtime (no. of days between flocks), probably a consequence of longer downtimes being associated with less focus on maintaining a high biosecurity level; broiler houses without a separate ante-room or barrier; and the use of the drinker nipples with cups or bells compared with nipples without cups. Additional country specific risk factors were also identified. For Norway, the risk of colonisation increased with increasing numbers of houses on a farm and when the water used for the broilers originated from surface water or bore holes instead of mains. For Denmark, having boot dips or low stocking density increased the risk of a flock becoming Campylobacter positive. The different model approaches allowed us to explore the effect of having a large

  2. Prevalence of Salmonella in broilers at retail outlets, processing plants and farms in Malaysia.

    PubMed

    Rusul, G; Khair, J; Radu, S; Cheah, C T; Yassin, R M

    1996-12-01

    A study was conducted to estimate the prevalence of Salmonella among broilers retailed at wet-markets and processing plants. Litter and feed samples obtained from both broiler and breeder farms were also examined for Salmonella. A total of 158 out of 445 (35.5%) and 52 out of 104 (50.0%) broiler carcasses obtained from wet-markets and processing plants were contaminated with Salmonella, respectively. Salmonella was isolated from 14 out of 98 (14.3%) samples of intestinal content. Litter samples from broiler and breeder farms were positive for Salmonella, 8/40 (20%) and 2/10 (20%), respectively. Salmonella isolates (230) belonging to 15 different serovars were isolated. Predominant serovars were S. enteritidis, S. muenchen, S. kentucky and S. blockley. PMID:8930704

  3. Prevalence and distribution of Eimeria species in broiler chicken farms of different capacities

    PubMed Central

    Györke, Adriana; Pop, Loredana; Cozma, Vasile

    2013-01-01

    We conducted a survey in broiler farms from Romania to establish prevalence and distribution of Eimeria species using single PCR assay. We found Eimeria spp. in 21 (91%) out of 23 flocks, and in 11 (92%) out of 12 farms. Four species of Eimeria were identified: E. acervulina (21/23; 91%), E. tenella (14/23; 61%), E. maxima (5/23; 22%) and E. praecox (3/23; 13%). Infection with a single species (E. acervulina) was detected in 6 (26%) infected flocks originated from large farms. Mixed infections were found in 15 (65%) flocks and the most prevalent combination was E. acervulina + E. tenella (8/23; 35%). Four flocks (17%) harboured mixed infection with E. acervulina + E. tenella + E. maxima. E. acervulina was significantly more prevalent in flocks that received ionophores as anticoccidial feed additives. PMID:24309007

  4. Effects of floor eggs on hatchability and later life performance in broiler chickens.

    PubMed

    van den Brand, H; Sosef, M P; Lourens, A; van Harn, J

    2016-05-01

    Two experiments were conducted in which effects of floor eggs, washed floor eggs, and clean nest eggs were investigated on incubation characteristics and performance in later life of broiler chickens. In both experiments, a young and an older breeder flock were used in a 3×2 factorial design during incubation. In the second experiment, male and female chickens were reared separately until d 35 of age in floor pens. During this grow out trial, an extra group was created in which chickens obtained from clean nest eggs were mixed with chickens obtained from floor eggs, meaning that grow out period was set up as a 4×2×2 factorial design with 4 egg types, 2 breeder ages, and 2 sexes. In both experiments, fertility and hatchability of fertile eggs were lower in floor and washed eggs than in clean nest eggs (hatchability: experiment 1: 74.4 vs. 70.6 vs. 92.6% for floor eggs, washed floor eggs and clean nest eggs, respectively, P<0.001; experiment 2: 78.3 vs. 81.7 vs. 90.2%, respectively, P<0.001). In experiment 2, BW at d 0 of chickens obtained from clean nest eggs was higher than that of chickens from floor eggs and washed floor eggs (41.5 vs. 40.4 and 40.3 g, respectively; P<0.001). This difference disappeared during the grow out period and was absent at slaughter age at d 35 of age. Feed intake (FI), feed conversion ratio (FCR), and mortality during the grow out period were not affected by egg type. Incidence and severity of hock burns and footpad dermatitis were not affected by egg type or breeder age. Litter friability at d 35 of age tended to be lower in pens with chickens obtained from washed floor eggs compared to clean nest eggs. We conclude that incubation of floor eggs or washed floor eggs resulted in lower fertility and hatchability compared to clean nest eggs, but that performance during the grow out period was not affected.

  5. Effects of floor eggs on hatchability and later life performance in broiler chickens.

    PubMed

    van den Brand, H; Sosef, M P; Lourens, A; van Harn, J

    2016-05-01

    Two experiments were conducted in which effects of floor eggs, washed floor eggs, and clean nest eggs were investigated on incubation characteristics and performance in later life of broiler chickens. In both experiments, a young and an older breeder flock were used in a 3×2 factorial design during incubation. In the second experiment, male and female chickens were reared separately until d 35 of age in floor pens. During this grow out trial, an extra group was created in which chickens obtained from clean nest eggs were mixed with chickens obtained from floor eggs, meaning that grow out period was set up as a 4×2×2 factorial design with 4 egg types, 2 breeder ages, and 2 sexes. In both experiments, fertility and hatchability of fertile eggs were lower in floor and washed eggs than in clean nest eggs (hatchability: experiment 1: 74.4 vs. 70.6 vs. 92.6% for floor eggs, washed floor eggs and clean nest eggs, respectively, P<0.001; experiment 2: 78.3 vs. 81.7 vs. 90.2%, respectively, P<0.001). In experiment 2, BW at d 0 of chickens obtained from clean nest eggs was higher than that of chickens from floor eggs and washed floor eggs (41.5 vs. 40.4 and 40.3 g, respectively; P<0.001). This difference disappeared during the grow out period and was absent at slaughter age at d 35 of age. Feed intake (FI), feed conversion ratio (FCR), and mortality during the grow out period were not affected by egg type. Incidence and severity of hock burns and footpad dermatitis were not affected by egg type or breeder age. Litter friability at d 35 of age tended to be lower in pens with chickens obtained from washed floor eggs compared to clean nest eggs. We conclude that incubation of floor eggs or washed floor eggs resulted in lower fertility and hatchability compared to clean nest eggs, but that performance during the grow out period was not affected. PMID:26908895

  6. Farm-Level Risk Factors for the Occurrence of Campylobacter in Broilers in Iceland

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction A longitudinal study was conducted in Iceland to identify the means to decrease the frequency of broiler flock colonization with Campylobacter, thereby reducing the burden of foodborne illness associated with poultry consumption. Our objective in this study was to identify risk factors...

  7. Hydrogen sulfide and nonmethane hydrocarbon emissions from broiler houses in the Southeastern United States

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Hydrogen sulfide (H2S) and nonmethane hydrocarbon (NMHC) emissions from two mechanically ventilated commercial broiler houses located in the Southeastern United States were continuously monitored over 12 flocks during the one-year period of 2006-2007 as a joint effort between Iowa State University a...

  8. Evaluation of filter-plating methods for simplified detection of Campylobacter associated with broiler cecal samples

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Campylobacter is natural member of the gut microflora in many commercial broilers and as such can become a contaminant on edible surfaces during processing. Culturing gut contents or feces can be a means to determine flock status prior to live-haul. However, the wide variety of non...

  9. Cultivation and qPCR Detection of Pathogenic and Antibiotic-Resistant Bacterial Establishment in Naive Broiler Houses.

    PubMed

    Brooks, J P; McLaughlin, M R; Adeli, A; Miles, D M

    2016-05-01

    Conventional commercial broiler production involves the rearing of more than 20,000 broilers in a single confined space for approximately 6.5 wk. This environment is known for harboring pathogens and antibiotic-resistant bacteria, but studies have focused on previously established houses with mature litter microbial populations. In the current study, a set of three naive houses were followed from inception through 11 broiler flocks and monitored for ambient climatic conditions, bacterial pathogens, and antibiotic resistance. Within the first 3 wk of the first flock cycle, 100% of litter samples were positive for and , whereas was cultivation negative but PCR positive. Antibiotic resistance genes were ubiquitously distributed throughout the litter within the first flock, approaching 10 to 10 genomic units g. Preflock litter levels were approximately 10 CFU g for heterotrophic plate count bacteria, whereas midflock levels were >10 colony forming units (CFU) g; other indicators demonstrated similar increases. The influence of intrahouse sample location was minor. In all likelihood, given that preflock levels were negative for pathogens and antibiotic resistance genes and 4 to 5 Log lower than flock levels for indicators, incoming birds most likely provided the colonizing microbiome, although other sources were not ruled out. Most bacterial groups experienced a cyclical pattern of litter contamination seen in other studies, whereas microbial stabilization required approximately four flocks. This study represents a first-of-its-kind view into the time required for bacterial pathogens and antibiotic resistance to colonize and establish in naive broiler houses. PMID:27136163

  10. Granuloma disease in flocks of productive layers caused by Tetratrichomonas gallinarum.

    PubMed

    Landman, W J M; Molenaar, R J; Cian, A; van der Heijden, H M J F; Viscogliosi, E

    2016-08-01

    In 2013, seven outbreaks of granuloma disease occurred in Dutch flocks of productive layers housed on different farms. These outbreaks were characterized by increased mortality and high incidence of granulomas, mainly in caeca (340/408 hens = 83%) and livers (69/408 hens = 17%). Mortality started to increase between 21 and 35 weeks of age and reached 3.7% to 11.0% exceeding the breeder's norm in periods ranging from 9 to 48 weeks. Some flocks also showed decreased egg production and/or loss of mean egg weight. All affected flocks were linked to one rearing farm, which therefore seemed to be the source of the disease. However, no signs of disease had been observed at this rearing farm. Sentinel hens placed in one of the affected flocks to determine whether the disease had an infectious nature developed granulomas identical to those seen in the outbreaks. Next, by fulfilling Koch's postulates it was shown that Tetratrichomonas gallinarum was the aetiological agent of the granuloma disease. The condition was reproduced in mature specified pathogen free White Leghorn hens (GD - Animal Health, Deventer, the Netherlands) by inoculation via both an artificial and a natural route with a well-defined axenic T. gallinarum isolate obtained from one of the affected flocks. Other causes of granuloma disease were excluded. PMID:26950827

  11. Preliminary survey on the impact of Schmallenberg virus on sheep flocks in South of Belgium.

    PubMed

    Saegerman, C; Martinelle, L; Dal Pozzo, F; Kirschvink, N

    2014-10-01

    Between late February and May 2012, a preliminary anonym survey was conducted among sheep farmers in south of Belgium in order to contribute to future estimations of the economic losses caused by Schmallenberg virus (SBV). Based on clinical signs consistent with SBV infection, this survey involved 13 meat sheep flocks considered as positive flocks with subsequent SBV detection by RT-qPCR [SBV-positive flocks (PF); total of 961 animals], and 13 meat sheep flocks considered as negative flocks (NF; total of 331 animals). These preliminary results indicated several significant characteristics that were more present in PF than in NF. These include an increased rate of abortions (6.7% in PF versus 3.2% in NF), of lambs born at term but presenting malformations (10.1% in PF versus 2.0% in NF) and of dystocia (10.1% in PF versus 3.4% in NF). Lamb mortality during the first week of life was reported more frequently in PF (8 of 13 PF, 61.5%) than in NF (1 of 13 NF, 7.7%). In PF, the observed prolificacy rate was 2-fold lower (93%) than expected (186%). The implementation of a survey at larger scale, including a high number of breeders, is necessary to allow a more detailed analysis of the SBV impact in the sheep sector.

  12. Farm and slaughterhouse characteristics affecting the occurrence of Salmonella and Campylobacter in the broiler supply chain.

    PubMed

    Franz, E; van der Fels-Klerx, H J; Thissen, J; van Asselt, E D

    2012-09-01

    Based on a data set on Campylobacter and Salmonella prevalence in the broiler supply chain, collected during the period 2002 through 2005 in the Netherlands, farm- and slaughterhouse-specific characteristics were tested for their effect on Campylobacter and Salmonella prevalence at different stages of the broiler supply chain. Three different sampling points were considered: departure from the farm, arrival at the slaughterhouse, and the end of the slaughterline. Strong associations were found between Salmonella and Campylobacter prevalence at a particular sampling point and their prevalence at the preceding point of the chain. Statistical analyses showed that the country of origin of the broiler farm had a significant effect on the prevalence of Salmonella and Campylobacter at slaughterhouse arrival. The feeding company delivering to the farm also showed a significant effect on the occurrence of both pathogens at departure from the broiler farm. The prevalence of Campylobacter decreased with an increasing number of birds per flock, whereas the prevalence of Salmonella increased with an increasing number of birds per flock. The number of flocks processed within a specific slaughterhouse was not associated with an increased or decreased prevalence of Campylobacter and Salmonella. The results provide more insight into factors related to the occurrence of both pathogens and in understanding their epidemiology. The results can be supportive in decision making on measures to reduce the contamination of broiler products with Salmonella and Campylobacter.

  13. [Veterinary treatment of pigeon flocks].

    PubMed

    Krautwald-Junghanns, M-E; Hofstetter, S; Schmidt, V

    2014-01-01

    Veterinary treatment of pigeon flocks requires specific knowledge on the management of the various pigeon flocks as well as of common diseases in these birds and important diagnostic and therapeutic measures. In this context, it is important to differentiate between racing pigeons, thoroughbreds and pigeons kept for meat production, that is, between food-supplying and companion animals. The following article provides an overview of the species-specific characteristics of Columba livia f. domestica and frequently occurring diseases as well as common therapeutic and prophylactic measures. PMID:25323217

  14. [Veterinary treatment of pigeon flocks].

    PubMed

    Krautwald-Junghanns, M-E; Hofstetter, S; Schmidt, V

    2014-01-01

    Veterinary treatment of pigeon flocks requires specific knowledge on the management of the various pigeon flocks as well as of common diseases in these birds and important diagnostic and therapeutic measures. In this context, it is important to differentiate between racing pigeons, thoroughbreds and pigeons kept for meat production, that is, between food-supplying and companion animals. The following article provides an overview of the species-specific characteristics of Columba livia f. domestica and frequently occurring diseases as well as common therapeutic and prophylactic measures.

  15. Development of a seroprevalence map for avian influenza in broiler chickens from Comunidad Valenciana, Spain.

    PubMed

    2014-12-01

    The aim of this study was to design and implement a seroprevalence map based on business intelligence for low pathogenicity notifiable avian influenza (LPNAI) in broilerchickens in Comunidad Valenciana (Spain). The software mapping tool developed for this study consisted of three main phases: data collection, data analysis and data representation. To obtain the serological data, the authors analysed 8,520 serum samples from broiler farms over three years. The data were represented on a map of Comunidad Valenciana, including geographical information of flock locations to facilitate disease monitoring. No clinical signs of LPNAI were reported in the studied flocks. The data from this study showed no evidence of contact with LPNAI in broiler flocks and the novel software mapping tool proved a valuable method for easily monitoring on the serological response to avian influenza information, including geographical information.

  16. Serological and molecular detection of avian pneumovirus in chickens with respiratory disease in Jordan.

    PubMed

    Gharaibeh, S M; Algharaibeh, G R

    2007-08-01

    Avian pneumovirus (APV) causes upper respiratory tract infection in chickens and turkeys. There is a serious respiratory disease in chickens, resulting in catastrophic economic losses to chicken farmers in Jordan. The objective of this study was to investigate the role of APV as a factor in the respiratory disease of chickens in Jordan by serological and molecular methods. Thirty-eight chicken flocks were examined by competitive ELISA (23 broilers, 8 layers, and 7 broiler breeders), and 150 chicken flocks were examined by reverse-transcription PCR (133 broiler flocks, 7 layer flocks, and 10 broiler breeder flocks). Avian pneumovirus antibodies were detected in 5 out of 23 broiler flocks (21.7%), 6 out of 8 layer flocks (75%), and 7 out of 7 broiler breeder flocks (100%). Avian pneumovirus nucleic acid was detected in 17 broiler flocks (12.8%) and 3 layer flocks (42.9%). None of the broiler breeder flocks tested by reverse-transcription PCR was positive. All of the 20 detected APV isolates were subtype B. This is the first report of APV infection in Jordan. In conclusion, the Jordanian poultry industry, vaccination programs should be adjusted to include the APV vaccine to aid in the control of this respiratory disease.

  17. Automated breeder fuel fabrication

    SciTech Connect

    Goldmann, L.H.; Frederickson, J.R.

    1983-09-01

    The objective of the Secure Automated Fabrication (SAF) Project is to develop remotely operated equipment for the processing and manufacturing of breeder reactor fuel pins. The SAF line will be installed in the Fuels and Materials Examination Facility (FMEF). The FMEF is presently under construction at the Department of Energy's (DOE) Hanford site near Richland, Washington, and is operated by the Westinghouse Hanford Company (WHC). The fabrication and support systems of the SAF line are designed for computer-controlled operation from a centralized control room. Remote and automated fuel fabriction operations will result in: reduced radiation exposure to workers; enhanced safeguards; improved product quality; near real-time accountability, and increased productivity. The present schedule calls for installation of SAF line equipment in the FMEF beginning in 1984, with qualifying runs starting in 1986 and production commencing in 1987. 5 figures.

  18. Evidence of broiler meat contamination with post-disinfection strains of Campylobacter jejuni from slaughterhouse.

    PubMed

    Kudirkienė, Eglė; Bunevičienė, Jurgita; Brøndsted, Lone; Ingmer, Hanne; Olsen, John Elmerdahl; Malakauskas, Mindaugas

    2011-03-01

    While cross-contamination from equipment and scalding water containing Campylobacter jejuni is considered the main route of broiler carcass contamination during slaughtering, alternative sources of C. jejuni may have been overlooked because only a limited number of studies focus on sampling of one broiler flock along the entire food chain and not many include the slaughterhouse environment. In the present study we have traced the changes of C. jejuni genotypes within one broiler flock from the beginning of rearing to the final product at the slaughterhouse with the aim to evaluate the dynamics and possible sources of carcass contamination with C. jejuni. Genotyping of 345 isolates of C. jejuni by flaA-RFLP revealed ten different flaA genotypes of C. jejuni along the broiler meat production chain. Broiler fillets were mainly contaminated with flaA genotypes found on the surfaces of slaughterhouse equipment and in the scalding water after cleaning and disinfection. Finally, it was clearly demonstrated that C. jejuni isolates remaining in the slaughterhouse environment after disinfection is a potential source of broiler meat contamination. Thus, identification of the mechanisms that allow such strains to persist in the slaughterhouse and survive cleaning is important for the establishment of future practices that will ensure sufficient reduction of C. jejuni in the slaughterhouse environment.

  19. EBIS charge breeder for CARIBU.

    PubMed

    Kondrashev, S; Barcikowski, A; Dickerson, C; Fischer, R; Ostroumov, P N; Vondrasek, R; Pikin, A

    2014-02-01

    A high-efficiency charge breeder based on an Electron Beam Ion Source (EBIS) is being developed by the ANL Physics Division to increase the intensity and improve the purity of accelerated radioactive ion beams. A wide variety of low-energy neutron-rich ion beams are produced by the Californium Rare Isotope Breeder Upgrade (CARIBU) for the Argonne Tandem Linac Accelerator System (ATLAS). These beams will be charge-bred by an EBIS charge breeder to a charge-to-mass ratio (q/A) ≥ 1/7 and accelerated by ATLAS to energies of about 10 MeV/u. The assembly of the CARIBU EBIS charge breeder except the injection/extraction beam lines has been completed. This summer we started electron beam commissioning of the EBIS. The first results on electron beam extraction, transport from the electron gun to a high power electron collector are presented and discussed. PMID:24593606

  20. EBIS charge breeder for CARIBU

    NASA Astrophysics Data System (ADS)

    Kondrashev, S.; Barcikowski, A.; Dickerson, C.; Fischer, R.; Ostroumov, P. N.; Vondrasek, R.; Pikin, A.

    2014-02-01

    A high-efficiency charge breeder based on an Electron Beam Ion Source (EBIS) is being developed by the ANL Physics Division to increase the intensity and improve the purity of accelerated radioactive ion beams. A wide variety of low-energy neutron-rich ion beams are produced by the Californium Rare Isotope Breeder Upgrade (CARIBU) for the Argonne Tandem Linac Accelerator System (ATLAS). These beams will be charge-bred by an EBIS charge breeder to a charge-to-mass ratio (q/A) ≥ 1/7 and accelerated by ATLAS to energies of about 10 MeV/u. The assembly of the CARIBU EBIS charge breeder except the injection/extraction beam lines has been completed. This summer we started electron beam commissioning of the EBIS. The first results on electron beam extraction, transport from the electron gun to a high power electron collector are presented and discussed.

  1. Histopathology and serum clinical chemistry evaluation of broilers with femoral head separation disorder

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Femoral head disarticulation (FHD) and necrosis is a sporadic leg problem of unknown etiology in broiler breeders. To determine the underlying physiology of FHD, the blood chemistry and the histopathology of the femoral heads of the affected chickens were compared with their age matched controls. Ch...

  2. Development of a new real-time polymerase chain reaction assay to detect Duck adenovirus A DNA and application to samples from Swiss poultry flocks.

    PubMed

    Schybli, Martina; Sigrist, Brigitte; Hess, Michael; van Leerdam, Bart; Hoop, Richard K; Vögtlin, Andrea

    2014-03-01

    Between 2008 and 2012, commercial Swiss layer and layer breeder flocks experiencing problems in laying performance were sampled and tested for infection with Duck adenovirus A (DAdV-A; previously known as Egg drop syndrome 1976 virus). Organ samples from birds sent for necropsy as well as blood samples from living animals originating from the same flocks were analyzed. To detect virus-specific DNA, a newly developed quantitative real-time polymerase chain reaction method was applied, and the presence of antibodies against DAdV-A was tested using a commercially available enzyme-linked immunosorbent assay. In 5 out of 7 investigated flocks, viral DNA was detected in tissues. In addition, antibodies against DAdV-A were detected in all of the flocks. PMID:24590667

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

    PubMed

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

    2015-03-01

    During the artificial insemination process, turkey breeder hens may become infected with influenza virus acquired from humans. The virus has been shown, through experimental infection, to localize in the reproductive tract, with limited dissemination in other tissues. A limited number of hens were used during these studies, and the overall flock morbidity, mortality, and fecundity were not able to be determined. The current case follows the progression of clinical signs in a flock of commercial breeder hens from onset of egg production losses in one house through the subsequent drops in four remaining houses. Each house contained approximately 3000 hens and followed a sequential loss of shell quality, reduced numbers of eggs, and fertility, while mild clinical signs were observed and mortality was slightly increased in a house with concurrent fowl cholera (Pasturella multocida) infection. PMID:26292554

  4. Impact of Antimicrobial Usage on Antimicrobial Resistance in Commensal Escherichia coli Strains Colonizing Broiler Chickens▿

    PubMed Central

    Smith, J. L.; Drum, D. J. V.; Dai, Y.; Kim, J. M.; Sanchez, S.; Maurer, J. J.; Hofacre, C. L.; Lee, M. D.

    2007-01-01

    Escherichia coli strains isolated from commercial broilers and an experimental flock of chickens were screened to determine phenotypic expression of antimicrobial resistance and carriage of drug resistance determinants. The goal of this study was to investigate the influence of oxytetracycline, sarafloxacin, and enrofloxacin administration on the distribution of resistance determinants and strain types among intestinal commensal E. coli strains isolated from broiler chickens. We detected a high prevalence of resistance to drugs such as tetracycline (36 to 97%), sulfonamides (50 to 100%), and streptomycin (53 to 100%) in E. coli isolates from treated and untreated flocks. These isolates also had a high prevalence of class 1 integron carriage, and most of them possessed the streptomycin resistance cassette, aadA1. In order to investigate the contribution of E. coli strain distribution to the prevalence of antimicrobial resistance and the resistance determinants, isolates from each flock were DNA fingerprinted by enterobacterial repetitive intergenic consensus sequence (ERIC) PCR. Although very diverse E. coli strain types were detected, four ERIC strain types were present on all of the commercial broiler farms, and two of the strains were also found in the experimental flocks. Each E. coli strain consisted of both susceptible and antimicrobial agent-resistant isolates. In some instances, isolates of the same E. coli strain expressed the same drug resistance patterns although they harbored different tet determinants or streptomycin resistance genes. Therefore, drug resistance patterns could not be explained solely by strain prevalence, indicating that mobile elements contributed significantly to the prevalence of resistance. PMID:17194843

  5. Prevalence and control of foot-pad dermatitis in broilers in Sweden.

    PubMed

    Ekstrand, C; Carpenter, T E; Andersson, I; Algers, B

    1998-07-01

    1. A cross-sectional observational study was carried out to investigate spatial, temporal and management aspects of foot-pad dermatitis in Swedish broilers. The efficacy of a control programme was evaluated. 2. Flock information on producer, breed, foodstuff manufacturer, region, abattoir, date of slaughter, age at slaughter, planned and actual stocking density was recorded. A total of 6988 flocks, representing approximately 110 million broilers was examined. A total of 175 broiler producers from 15 geographical regions is represented. 3. The total foot-pad score per flock ranged from 0 to 200, with a mean of 34.7 and a standard deviation of 40.9. 4. Simple linear regression analysis showed that the mean total score on a weekly basis decreased (P < 0.001) over time, mainly because of a decrease in the prevalence of severe foot-pad lesions. 5. There was an association (P < 0.05) between slaughterhouse, foodstuff supplier and geographic region respectively and the mean total foot pad score of the flocks slaughtered.

  6. Cefotaxime-resistant Escherichia coli in broiler farms-A cross-sectional investigation in Germany.

    PubMed

    Hering, Johanna; Frömke, Cornelia; von Münchhausen, Christiane; Hartmann, Maria; Schneider, Bettina; Friese, Anika; Rösler, Uwe; Kreienbrock, Lothar; Hille, Katja

    2016-03-01

    In this investigation the farm prevalence of cefotaxime-resistant Escherichia coli (CREC) in German broiler farms was evaluated. In total, 59 flocks on 34 broiler farms were sampled in four agricultural regions of Germany. Per broiler flock, three faecal samples, a pair of boot swabs and one dust sample were taken and examined for the presence of CREC. After pre-enrichment of sample material in Luria-Bertani-broth, the broth was streaked onto MacConkey agar containing 1mg/l cefotaxime (CTX). CREC isolates were detected in at least one sample from each flock resulting in a farm prevalence of 100%. The proportion of positive samples was high in all three sample types. Of 177 collective faecal samples 81.9% were positive, of 59 boot swabs and 59 dust samples 79.7% and 62.7% were positive. In conclusion, the prevalence of broiler farms with cefotaxime-resistant E. coli in Germany is very high. We suggest that the analysis of collective faecal samples is sufficient to determine the CREC farm status. In addition to other studies our study supports the finding that cefotaxime resistance is a good proxy for the presence of ESBL- or plasmidic AmpC-beta-lactamases. PMID:26783199

  7. Statistical mechanics for natural flocks of birds.

    PubMed

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

    2012-03-27

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

  8. Yolk absorption and embryo development of small and large eggs originating from young and old breeder hens.

    PubMed

    Nangsuay, A; Ruangpanit, Y; Meijerhof, R; Attamangkune, S

    2011-11-01

    To evaluate the effect of breeder age and egg size on yolk absorption and embryo development, a total of 4,800 Ross 308 hatching eggs were subjected to 4 treatments arranged in a 2 × 2 factorial randomized complete block design using 2 breeder ages (29 and 53 wk of age, or young and old) and 2 egg sizes (57-61 g and 66-70 g, or small and large). A significant interaction between breeder age and egg size was found for egg composition. Yolk weight increased with flock age, whereas a larger egg size resulted in higher albumen content. A significant interaction between breeder age and egg size was found for yolk-free body (YFB) weight only at d 7. Until the fourteenth day of incubation, eggs from the old flock yielded greater YFB weight than did eggs from the young flock. At hatch, chicks of both age groups had comparable wet YFB weight, chick weight, wet and dry residual yolk weight, and chick length. Dry YFB weight of chicks from the old flock was higher than that of chicks from the young flock. Compared with the small eggs, embryos and chicks of the large eggs had greater YFB weight from d 14 to hatching. At hatch, these chicks were also heavier, longer, and had higher wet and dry YFB and residual yolk weight. Yolk absorption at d 18 and at hatch of embryos and chicks of the old flock was higher than that of the young flock, both in absolute values and percentages. Rates of absolute and percentage yolk absorption through d 18 and percentage yolk absorption at hatch were higher in the small eggs than in the large eggs. It can be concluded that egg size influences chick length at hatch and embryo development when expressed in terms of total and YFB weight. Although yolk availability and rate of absorption may have influenced dry YFB weight, they did not influence hatching chick length or total and YFB weight.

  9. An index for quantifying flocking behavior.

    PubMed

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

    2007-12-01

    One of the classic research topics in adaptive behavior is the collective displacement of groups of organisms such as flocks of birds, schools of fish, herds of mammals, and crowds of people. However, most agent-based simulations of group behavior do not provide a quantitative index for determining the point at which the flock emerges. An index was developed of the aggregation of moving individuals in a flock and an example was provided of how it can be used to quantify the degree to which a group of moving individuals actually forms a flock. PMID:18229552

  10. Presence of Salmonella in the crop and ceca of broiler chickens before and after preslaughter feed withdrawal.

    PubMed

    Corrier, D E; Byrd, J A; Hargis, B M; Hume, M E; Bailey, R H; Stanker, L H

    1999-01-01

    Recent studies have suggested that crop contents may serve as an important source of Salmonella carcass contamination within processing plants. During the present study, we evaluated the effect of preslaughter feed withdrawal on the presence of Salmonella in the crops of broilers from nine commercial broiler flocks reared in individual growout houses. Crops were collected aseptically from 40 randomly selected broilers in each flock before feed removal and at the end of the feed withdrawal period, immediately before capture and transport to the processing plant. Similarly, the ceca were collected before and after feed withdrawal in six of the nine broiler flocks. The presence of Salmonella in the crops and ceca was determined by enrichment culture in tetrathionate broth followed by culture on brilliant green agar. The incidence of Salmonella in crop contents increased significantly (P < 0.05) in five of the nine flocks during feed withdrawal. The total number of Salmonella contaminated crops from all nine flocks increased significantly (P < 0.005) from 7/360 (1.9%) before feed removal to 36/359 (10.0%) at the end of feed withdrawal. The increased incidence of Salmonella in the crop contents was associated with an increased tendency of the broilers to consume contaminated rearing house litter during feed withdrawal. The incidence of Salmonella in the ceca increased nonsignificantly from 14/240 (5.8%) before feed removal to 19/240 (7.9%) at the end of feed withdrawal. The results indicate that the incidence of Salmonella crop contamination may increase as much as fivefold during preslaughter feed withdrawal and represent a critical preharvest control point in reducing Salmonella entry into the processing plant. PMID:10023745

  11. Fusion Breeder Program interim report

    SciTech Connect

    Moir, R.; Lee, J.D.; Neef, W.

    1982-06-11

    This interim report for the FY82 Fusion Breeder Program covers work performed during the scoping phase of the study, December, 1981-February 1982. The goals for the FY82 study are the identification and development of a reference blanket concept using the fission suppression concept and the definition of a development plan to further the fusion breeder application. The context of the study is the tandem mirror reactor, but emphasis is placed upon blanket engineering. A tokamak driver and blanket concept will be selected and studied in more detail during FY83.

  12. NUCLEAR REACTOR FUEL-BREEDER FUEL ELEMENT

    DOEpatents

    Currier, E.L. Jr.; Nicklas, J.H.

    1962-08-14

    A fuel-breeder fuel element was developed for a nuclear reactor wherein discrete particles of fissionable material are dispersed in a matrix of fertile breeder material. The fuel element combines the advantages of a dispersion type and a breeder-type. (AEC)

  13. Risk and indicators of condemnation of male turkey broilers in western France, February-July 2006.

    PubMed

    Lupo, C; Le Bouquin, S; Allain, V; Balaine, L; Michel, V; Petetin, I; Colin, P; Chauvin, C

    2010-05-01

    A field study was conducted to estimate the sanitary condemnation proportion in male turkey broiler flocks, to describe the reasons for condemnation and the related macroscopic lesions, and to investigate whether primary production information would predict the risk of condemnation. Male turkey standard broiler flocks (117) were randomly selected in the 13 slaughterhouses located in Western France, from February to July 2006. The flocks were monitored from their arrival at the slaughterhouse until the results of the post mortem sanitary inspection. Information about rearing conditions, health history, catching and loading conditions, transportation to the slaughterhouse and slaughtering was also collected. Sampling design was considered in the calculations and the condemnation proportion was modelled using a negative binomial regression, accounting for clustering within slaughterhouse. The within-flock weighted average condemnation proportion was 1.8% (95% confidence interval, 1.3-2.3%). Emaciation, arthritis-polyarthritis and congestion were the main reported official reasons for condemnation, representing 76% of the condemned carcases. Three variables were significantly associated with increased risk of condemnation: observed locomotor disorders on the farm, high cumulative mortality 2 weeks before slaughter, and clinical signs observed by the Veterinary Services during the ante mortem inspection at the slaughterhouse. The final model explained 35% of the total variation in condemnation risk. Half of this explained variation could be attributed to locomotor disorders observed during rearing. The sensitivity and specificity of the model to predict a high flock condemnation risk were 80% and 74%, respectively, when using an optimum threshold of 0.95% to define high risk. The results of this study suggested that the variables found to be associated with condemnation proportion were markers of increased risk and could be used as indicators. These risk indicators can

  14. Viral infections in goose flocks in Poland.

    PubMed

    Kozdruń, W; Woźniakowski, G; Samorek-Salamonowicz, E; Czekaj, H

    2012-01-01

    The aim of this study was to determine the infectious agents isolated from infection - suspected geese sent for the diagnostic examination to National Veterinary Research Institute. The birds were sent from goose flocks localized in different parts of Poland. Totally, 1,013 birds from 122 flocks were examined. The presence of goose parvovirus (GPV), goose haemorrhagic polyomavirus (GHPV), and goose circovirus (GoCV) was detected by triplex PCR. The presence of GPV DNA was shown in 36 flocks. The disease was most frequently diagnosed in goslings aging 3.5 weeks (ten flocks), and 2.5 weeks (six flocks). The analysis of the nucleotide sequence of VP1 encoding region has shown close similarity of Polish GPV strains within the group which ranged from 92% to 100%. Moreover, the similarity level of these strains with GPV isolated in Europe was from 91.3% to 100%. The occurrence of GoCV DNA was shown in 25 goose flocks. The presence of GoCV DNA was found among geese aged from 2 to 6 weeks, but predominantly in those aging 3.5 (three flocks) and 5 weeks (five flocks). The sequence analysis of PCR products from the sequenced region of ORFC1 capsid protein of GoCV has shown that Polish isolates share from 85% to 91% similarity with the sequences of GoCV strains isolated in other countries. The presence of DNA of GHPV was found in 3-week-old geese. During the last 2 years the presence of GHPV was confirmed in three flocks of goslings at the age from 3 to 3.5 weeks. During the last 12 years the occurrence of co-infection with GPV and GoCV was detected in six flocks aging from 5 to 6 weeks.

  15. Molecular Epidemiology of Avian Leukosis Virus Subgroup J in Layer Flocks in China

    PubMed Central

    Gao, Yulong; Yun, Bingling; Qin, Liting; Pan, Wei; Qu, Yue; Liu, Zaisi; Wang, Yongqiang; Qi, Xiaole; Gao, Honglei

    2012-01-01

    Avian leukosis virus subgroup J (ALV-J) was first isolated from meat-type chickens in 1988. No field cases of ALV-J infection or tumors in layer chickens were observed worldwide until 2004. However, layer flocks in China have experienced outbreaks of this virus in recent years. The molecular epidemiology of ALV-J strains isolated from layer flocks was investigated. The env genes of 77.8% (21/27) of the ALV-J layer isolates with a high degree of genetic variation were significantly different from the env genes of the prototype strain of ALV-J (HPRS-103) and American and Chinese strains from meat-type chickens (designated ALV-J broiler isolates). A total of 205 nucleotides were deleted from the 3′ untranslated region of 89.5% (17/19) of the ALV-J layer isolates. Approximately 94.7% (16/17) of the layer isolates contained a complete E element of 146 to 149 residues. The U3 sequences of 84.2% (16/19) of the ALV-J layer isolates displayed less than 92.5% sequence homology to those of the ALV-J broiler isolates, although the transcriptional regulatory elements that are typical of avian retroviruses were highly conserved. Several unique nucleotide substitutions in the env gene, the U3 region, and the E element of most of the ALV-J layer isolates were detected. These results suggested that the env gene, E element, and U3 region in the ALV-J layer isolates have evolved rapidly and were significantly different from those of the ALV-J broiler isolates. These findings will contribute to a better understanding of the pathogenic mechanism of layer tumor diseases induced by ALV-J. PMID:22205787

  16. Clinical and morphological investigations on the incidence of forms of rickets and their association with other pathological states in broiler chickens.

    PubMed

    Dinev, I

    2012-04-01

    The purpose of investigations was to determine, by means of pathomorphological methods, the incidence of different rickets forms and their role for the occurrence of other illnesses in broiler chickens in Bulgaria. Clinical, blood biochemical, gross anatomy and histological investigations were carried out in broiler chickens with signs of rickets. The studies were performed in 12 broiler flocks in 4 farms located in different regions of the country. Based on macro- and microscopic lesions, alterations specific for hypocalcaemic rickets were observed in two farms, whereas signs of hypophosphataemic rickets - in the other two. The rickets diagnosis was confirmed by analysis of blood serum calcium, magnesium and inorganic phosphate concentrations. At the age of 30-35 days, various pathological states were observed in the same farms. The presented results suggested that existing problems in studied flocks were associated with an earlier occurrence of rickets.

  17. Cryptosporidiosis in broiler chickens in Zhejiang Province, China: molecular characterization of oocysts detected in fecal samples.

    PubMed

    Wang, Lengmei; Xue, Xue; Li, Jianqiu; Zhou, Qianjin; Yu, Yingchao; Du, Aifang

    2014-01-01

    Cryptosporidium is one of the most important parasites in poultry, and this pathogen can infect more than 30 avian species. The present study investigated the infection rate of Cryptosporidium among broiler chicken flocks. A total of 385 fecal samples from broiler chickens in 7 regions of Zhejiang Province collected from November 2010 to January 2012 were examined by microscopy. Thirty-eight (10%) samples were positive for Cryptosporidium infection, and 3 genotypes (Cryptosporidium baileyi, Cryptosporidium meleagridis, and avian genotype II) were identified by PCR and sequencing. A phylogenetic tree of the isolates was analyzed. These results suggest that cryptosporidiosis is widespread in poultry in Zhejiang Province, and is a potential threat to public health as well as the economy. This is the first report about the infection rate and molecular characterization of Cryptosporidium in broiler chickens in Zhejiang. PMID:25075975

  18. Cryptosporidiosis in broiler chickens in Zhejiang Province, China: molecular characterization of oocysts detected in fecal samples.

    PubMed

    Wang, Lengmei; Xue, Xue; Li, Jianqiu; Zhou, Qianjin; Yu, Yingchao; Du, Aifang

    2014-01-01

    Cryptosporidium is one of the most important parasites in poultry, and this pathogen can infect more than 30 avian species. The present study investigated the infection rate of Cryptosporidium among broiler chicken flocks. A total of 385 fecal samples from broiler chickens in 7 regions of Zhejiang Province collected from November 2010 to January 2012 were examined by microscopy. Thirty-eight (10%) samples were positive for Cryptosporidium infection, and 3 genotypes (Cryptosporidium baileyi, Cryptosporidium meleagridis, and avian genotype II) were identified by PCR and sequencing. A phylogenetic tree of the isolates was analyzed. These results suggest that cryptosporidiosis is widespread in poultry in Zhejiang Province, and is a potential threat to public health as well as the economy. This is the first report about the infection rate and molecular characterization of Cryptosporidium in broiler chickens in Zhejiang.

  19. Accelerator breeders: will they replace liquid metal fast breeders

    SciTech Connect

    Grand, P.; Powell, J.R.; Steinberg, M.; Takahashi, H.

    1983-06-01

    Investigation of accelerator breeders at Brookhaven National Laboratory indicate that the AB-LWR fuel cycle is economically competitive with the LMFBR fuel cycle. The same can be said about the accelerator breeder-High Temperature Gas Reactor symbiosis. This system appears to be very competitive with the added real advantage of superior safety and proliferation resistance. This discussion would be incomplete if the real competitor to accelerator breeding was not mentioned, namely Fusion Hybrid Breeding (FHB). Fusion Hybrid Breeding is a nearer option than pure fusion, as the breakeven Q value requirements are much more modest. Fusion Hybrid Breeding, if successful and practical, has the potential for highly efficient fissile fuel breeding, leading to cheaper fuel. The system, however, has yet to be demonstrated scientifically and to be shown commercially feasible. This is in contrast with the AB system which is an extension of proven, state-of-the-art technology with implementation possible within twenty years. 25 references, 4 figures, 5 tables.

  20. Research on an Infectious Disease Transmission by Flocking Birds

    PubMed Central

    Mao, Xinjun; Guessoum, Zahia

    2013-01-01

    The swarm intelligence is becoming a hot topic. The flocking of birds is a natural phenomenon, which is formed and organized without central or external controls for some benefits (e.g., reduction of energy consummation). However, the flocking also has some negative effects on the human, as the infectious disease H7N9 will easily be transmited from the denser flocking birds to the human. Zombie-city model has been proposed to help analyzing and modeling the flocking birds and the artificial society. This paper focuses on the H7N9 virus transmission in the flocking birds and from the flocking birds to the human. And some interesting results have been shown: (1) only some simple rules could result in an emergence such as the flocking; (2) the minimum distance between birds could affect H7N9 virus transmission in the flocking birds and even affect the virus transmissions from the flocking birds to the human. PMID:23864820

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

    PubMed

    Tang, Mingsheng; Mao, Xinjun; Guessoum, Zahia

    2013-01-01

    The swarm intelligence is becoming a hot topic. The flocking of birds is a natural phenomenon, which is formed and organized without central or external controls for some benefits (e.g., reduction of energy consummation). However, the flocking also has some negative effects on the human, as the infectious disease H7N9 will easily be transmited from the denser flocking birds to the human. Zombie-city model has been proposed to help analyzing and modeling the flocking birds and the artificial society. This paper focuses on the H7N9 virus transmission in the flocking birds and from the flocking birds to the human. And some interesting results have been shown: (1) only some simple rules could result in an emergence such as the flocking; (2) the minimum distance between birds could affect H7N9 virus transmission in the flocking birds and even affect the virus transmissions from the flocking birds to the human. PMID:23864820

  2. Can breeder reproductive status, performance and egg quality be enhanced by supplementation and transition of n-3 fatty acids?

    PubMed

    Delezie, E; Koppenol, A; Buyse, J; Everaert, N

    2016-08-01

    The aim of this experiment was to investigate the effect of n-3 fatty acid (FA) supplemented diets on breeder performance, productivity and egg quality. Breeders (n = 480) were fed the supplemented diet from 18 weeks onwards; the inclusion level of n-3 FA was increased from 1.5% to 3.0% from 34 weeks of age onwards until 48 weeks of age. Ross-308 broiler breeders (n = 480) were fed one of four different diets: a basal diet rich in n-6 FA (control diet) or one of three diets rich in n-3 FA. For the n-3 FA diets, eicosapentaenoic acid (EPA, 20:5 n-3) and docosahexaenoic acid (DHA, 22:6 n-3) were fed to the broiler breeders at different ratios formulated to obtain EPA/DHA ratios of 1/1, 1/2 or 2/1. Differences in performance, reproduction and egg quality parameters due to n-3 supplementation were noted more for the 1.5% followed by the 3.0% fed broilers than their 1.5% supplemented counterparts. Egg weight (p < 0.001) and egg mass (p = 0.003) were significantly lower and feed conversion (p = 0.008) significantly higher for the n-3 FA (at 3.0% inclusion level) fed broilers compared to the control group. For the EPA- and DHA-fed breeders, a higher proportional abdominal fat percentage (p = 0.025) and proportional albumen weight (%) (p = 0.041) were found respectively. Dietary treatments did not affect reproduction. It can be concluded that the results of the present experiment indicate no significant differences between treatments at 1.5% inclusion levels. However, increasing this level to 3.0% is not recommended due to the rather negative effects on the measured parameters. It should be further investigated whether these adverse effects were obtained due to (i) the higher supplementation level, (ii) combining a supplementation level of 1.5% with 3% or (iii) the duration of supplementation.

  3. Kinematic analysis quantifies gait abnormalities associated with lameness in broiler chickens and identifies evolutionary gait differences.

    PubMed

    Caplen, Gina; Hothersall, Becky; Murrell, Joanna C; Nicol, Christine J; Waterman-Pearson, Avril E; Weeks, Claire A; Colborne, G Robert

    2012-01-01

    This is the first time that gait characteristics of broiler (meat) chickens have been compared with their progenitor, jungle fowl, and the first kinematic study to report a link between broiler gait parameters and defined lameness scores. A commercial motion-capturing system recorded three-dimensional temporospatial information during walking. The hypothesis was that the gait characteristics of non-lame broilers (n = 10) would be intermediate to those of lame broilers (n = 12) and jungle fowl (n = 10, tested at two ages: immature and adult). Data analysed using multi-level models, to define an extensive range of baseline gait parameters, revealed inter-group similarities and differences. Natural selection is likely to have made jungle fowl walking gait highly efficient. Modern broiler chickens possess an unbalanced body conformation due to intense genetic selection for additional breast muscle (pectoral hypertrophy) and whole body mass. Together with rapid growth, this promotes compensatory gait adaptations to minimise energy expenditure and triggers high lameness prevalence within commercial flocks; lameness creating further disruption to the gait cycle and being an important welfare issue. Clear differences were observed between the two lines (short stance phase, little double-support, low leg lift, and little back displacement in adult jungle fowl; much double-support, high leg lift, and substantial vertical back movement in sound broilers) presumably related to mass and body conformation. Similarities included stride length and duration. Additional modifications were also identified in lame broilers (short stride length and duration, substantial lateral back movement, reduced velocity) presumably linked to musculo-skeletal abnormalities. Reduced walking velocity suggests an attempt to minimise skeletal stress and/or discomfort, while a shorter stride length and time, together with longer stance and double-support phases, are associated with

  4. Farmers flock to coastal cities.

    PubMed

    Zhou, M; Mulley, S

    1994-01-01

    China's rural-urban migration flows, particularly into Shanghai, Guangdong province, Beijing, and coastal areas, present challenges for urban development. The impact on rural and urban areas and suggestions for minimizing undesirable consequences were discussed. Professor Zhang Qingwu, deputy director of the Population Research Institute of Xiamen University in Fujian province, believes that the large migrating populations and those without residence cards pose problems for heavily populated cities: they strain resources (housing, water and electricity supplies, transportation, telecommunication, environmental hygiene, food supplies, and educational facilities). Crime increases. Municipal departments must increase their administrative load in service sectors. The general idea is that rural-to-urban migration reflects social progress and adds to a productive work force. Flexible policies are recommended. In Guangdong province, where migrants arrived from Sichuan and Hunan provinces, counties from the latter two provinces have established offices for supervising their former residents. Employment adjustment can be anticipated when the major flock of migrants arrive after the Lantern Festival. Professor Gui Shixun of the Population Research Institute of East China Normal University and advisor to the State Family Planning Commission recommends that development strategies incorporate planning for imbalances between local population and migrant urban workers. In some areas, women represent the bulk of migrants, while in other areas men do. Cultural development should be stressed, with investments also improved in telecommunications, traffic and transportation, education, and hygiene. Professor Jiang Zhixue recommends shifting from labor-intensive enterprises to technology-intensive enterprises and a better trained work force. Other schemes, such as the purchase by migrants of residence cards in Xiamen, would entitle migrants to the same rights and obligations as

  5. Prevalence and characterization of Salmonella infantis isolates originating from different points of the broiler chicken-human food chain in Hungary.

    PubMed

    Nógrády, N; Kardos, G; Bistyák, A; Turcsányi, I; Mészáros, J; Galántai, Zs; Juhász, A; Samu, P; Kaszanyitzky, J E; Pászti, J; Kiss, I

    2008-09-30

    During the 10-month study period Salmonella contamination of broiler houses and the flocks reared in three farms (A, B and C), the slaughter houses where the flocks were slaughtered, as well as the carcass and retail raw meat products originating from them was investigated. In the broiler farm A five consecutive flocks, in the B and C farms one flock was sampled. Environmental samples were taken prior to the introductions. Environmental, drinking water, feed and faecal samples were collected regularly using standard methods. Before and during processing of the flocks, environmental and carcass samples were taken at the abattoirs. Salmonella contamination of the carcass, retail meat, as well as stool samples of farm and abattoir workers and from human illnesses registered in the same period and region were also examined. Isolation, sero-, phage- and antibiotic resistance typing, class 1 integron and plasmid profiling of the strains were performed; their genetic relationship was assessed by PFGE. Although the broiler house and the faecal samples of the 5 flocks of the farm A were negative for Salmonella, S. infantis was isolated from 20-100% of the abattoir carcass samples. The retail raw meat samples were 0-100% S. infantis positive. The environmental samples of farm B were Salmonella negative, but the examined flock was contaminated: S. infantis was identified from 43% of the faecal samples. This serotype was identified in 100% of the carcass and retail raw meat samples. From environmental samples taken before the arrival of the 1-day-old chicks in the broiler house C, S. infantis was cultured. S. infantis prevalence in the faecal samples was 35% and all the carcass and retail raw meat samples were S. infantis contaminated. Altogether 164 S. infantis strains were isolated out of which 145 were further characterized. The vast majority (142/145) of the strains belonged to phage types 217 and 213. All but one were characterized by the nalidixic acid

  6. Breeder Reactors, Understanding the Atom Series.

    ERIC Educational Resources Information Center

    Mitchell, Walter, III; Turner, Stanley E.

    The theory of breeder reactors in relationship to a discussion of fission is presented. Different kinds of reactors are characterized by the cooling fluids used, such as liquid metal, gas, and molten salt. The historical development of breeder reactors over the past twenty-five years includes specific examples of reactors. The location and a brief…

  7. Diffusion of individual birds in starling flocks.

    PubMed

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

    2013-04-01

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

  8. Diffusion of individual birds in starling flocks

    PubMed Central

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

    2013-01-01

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

  9. Diversity of pulsed-field gel electrophoresis profiles of Campylobacter jejuni and Campylobacter coli from broiler chickens in France.

    PubMed

    Denis, M; Rose, V; Huneau-Salaün, A; Balaine, L; Salvat, G

    2008-08-01

    In 2003 to 2004, 26 free-range broilers flocks excreting Campylobacter were studied for identification of Campylobacter species and genotype diversity. Seventeen flocks were sampled at the end of the indoor rearing period and 9 before departure to the slaughterhouse after access to an open area. Out of 513 isolates, 315 were identified as Campylobacter jejuni and 198 as Campylobacter coli. Pulsed-field gel electrophoresis analysis revealed 35 genotypes for C. jejuni and 43 genotypes for C. coli; 38.4% of the isolates were clustered into 16 genetic groups. This kind of poultry production system is characterized by a large number of Campylobacter coli isolates. Flocks sampled during the indoor phase were predominantly contaminated by C. jejuni, whereas those sampled during warm months were predominantly contaminated by C. coli. The Campylobacter population was genetically highly diverse: multiple genotypes were detected in a single flock. Six flocks were each found to harbor a mixture of genotypes; these isolates were genetically closely related and were grouped into clusters of at least 80% genetic similarity. Isolates with genotypes found in different flocks and strains, but sharing the same genetic clusters, were detected in different farms and at different times in the year. Flocks sampled during the indoor rearing period and when farmers use fresh farm-made litter were associated with a small number of clusters. In conclusion, Campylobacter species were genetically highly diverse. Our findings suggest the presence of genomic rearrangements in Campylobacter colonizing the chick intestine and that some Campylobacter strains are adapted to poultry. In addition, the species diversity in the flocks was affected by season and cloistering measures. Litter and exposure to an open area were likely sources of flock Campylobacter contamination.

  10. Evaluation of White Striping prevalence and predisposing factors in broilers at slaughter.

    PubMed

    Russo, Elisa; Drigo, Michele; Longoni, Corrado; Pezzotti, Raffaele; Fasoli, Paolo; Recordati, Camilla

    2015-08-01

    White striping ( WS: ) is an alteration of breast and thigh muscles of broiler chickens characterized by the presence of white striations parallel to the direction of muscle fibers. This study was performed to evaluate the prevalence and the predisposing factors to WS in commercial broilers of different weight reared in northern Italy. Fifty seven broiler flocks, including animals of medium- and heavy-weight, were grossly evaluated at slaughter for the presence of WS. For each flock, breeding data (mean BW at slaughter, ADG, sex, color of skin and fat, genetic line, age, antibiotic treatment, and prevalence of deep pectoral myopathy) were collected and statistically analyzed to assess their correlation with WS. Histology of breast fillets affected by different grades of WS was performed to evaluate potential differences between medium- and heavy-weight broilers. The overall prevalence of WS in medium- and heavy-weight broilers (mean BW 2.59 ± 0.13 kg and 3.64 ± 0.34 kg, respectively) was 70.2 ± 7.9% and 82.51 ± 8.5%, respectively, while the percentage of severe WS was 13.3 ± 7.1% and 25.7 ± 12.8%, respectively. A strong correlation was found between presence of WS, BW at slaughter, and ADG (Pearson correlation = 0.69, P < 0.01; Pearson correlation = 0.67, P < 0.01). WS also closely correlated with the prevalence of deep pectoral myopathy (Spearman's Rho slaughterhouse 1 = 0.74, Spearman's Rho slaughterhouse 2 = 0.51, P < 0.01). No correlation was found between genetics or sanitary status of the flock and WS. Histology confirmed that breasts with WS lesions were affected by a polyphasic degenerative and necrotizing myopathy, and that the lesions, as expected, were more severe in heavy-weight broilers. In conclusion, WS is a major concern in commercial meat poultry reared in Italy, affecting more severely heavier broilers, and it is mainly related to the BW and ADG of animals. PMID:26112037

  11. Flocking and invariance of velocity angles.

    PubMed

    Liu, Le; Huang, Lihong; Wu, Jianhong

    2016-04-01

    Motsch and Tadmor considered an extended Cucker-Smale model to investigate the flocking behavior of self-organized systems of interacting species. In this extended model, a cone of the vision was introduced so that outside the cone the influence of one agent on the other is lost and hence the corresponding influence function takes the value zero. This creates a problem to apply the Motsch-Tadmor and Cucker-Smale method to prove the flocking property of the system. Here, we examine the variation of the velocity angles between two arbitrary agents, and obtain a monotonicity property for the maximum cone of velocity angles. This monotonicity permits us to utilize existing arguments to show the flocking property of the system under consideration, when the initial velocity angles satisfy some minor technical constraints. PMID:27105986

  12. Phase Transitions in Models of Bird Flocking

    NASA Astrophysics Data System (ADS)

    Christodoulidi, H.; van der Weele, K.; Antonopoulos, Ch. G.; Bountis, T.

    2014-12-01

    The aim of the present paper is to elucidate the transition from collective to random behavior exhibited by various mathematical models of bird flocking. In particular, we compare Vicsek's model [Vicsek et al., Phys. Rev. Lett. 75, 1226-1229 (1995)] with one based on topological considerations. The latter model is found to exhibit a first order phase transition from flocking to decoherence, as the "noise parameter" of the problem is increased, whereas Vicsek's model gives a second order transition. Refining the topological model in such a way that birds are influenced mostly by the birds in front of them, less by the ones at their sides and not at all by those behind them (because they do not see them), we find a behavior that lies in between the two models. Finally, we propose a novel mechanism for preserving the flock's cohesion, without imposing artificial boundary conditions or attractive forces.

  13. Functional Diversification within a Predatory Species Flock

    PubMed Central

    Burress, Edward D.; Duarte, Alejandro; Serra, Wilson S.; Loueiro, Marcelo; Gangloff, Michael M.; Siefferman, Lynn

    2013-01-01

    Ecological speciation is well-known from adaptive radiations in cichlid fishes inhabiting lentic ecosystems throughout the African rift valley and Central America. Here, we investigate the ecological and morphological diversification of a recently discovered lotic predatory Neotropical cichlid species flock in subtropical South America. We document morphological and functional diversification using geometric morphometrics, stable C and N isotopes, stomach contents and character evolution. This species flock displays species-specific diets and skull and pharyngeal jaw morphology. Moreover, this lineage appears to have independently evolved away from piscivory multiple times and derived forms are highly specialized morphologically and functionally relative to ancestral states. Ecological speciation played a fundamental role in this radiation and our data reveal novel conditions of ecological speciation including a species flock that evolved: 1) in a piscivorous lineage, 2) under lotic conditions and 3) with pronounced morphological novelties, including hypertrophied lips that appear to have evolved rapidly. PMID:24278349

  14. Thermal breeder fuel enrichment zoning

    DOEpatents

    Capossela, Harry J.; Dwyer, Joseph R.; Luce, Robert G.; McCoy, Daniel F.; Merriman, Floyd C.

    1992-01-01

    A method and apparatus for improving the performance of a thermal breeder reactor having regions of higher than average moderator concentration are disclosed. The fuel modules of the reactor core contain at least two different types of fuel elements, a high enrichment fuel element and a low enrichment fuel element. The two types of fuel elements are arranged in the fuel module with the low enrichment fuel elements located between the high moderator regions and the high enrichment fuel elements. Preferably, shim rods made of a fertile material are provided in selective regions for controlling the reactivity of the reactor by movement of the shim rods into and out of the reactor core. The moderation of neutrons adjacent the high enrichment fuel elements is preferably minimized as by reducing the spacing of the high enrichment fuel elements and/or using a moderator having a reduced moderating effect.

  15. Light-Water Breeder Reactor

    DOEpatents

    Beaudoin, B. R.; Cohen, J. D.; Jones, D. H.; Marier, Jr, L. J.; Raab, H. F.

    1972-06-20

    Described is a light-water-moderated and -cooled nuclear breeder reactor of the seed-blanket type characterized by core modules comprising loosely packed blanket zones enriched with fissile fuel and axial zoning in the seed and blanket regions within each core module. Reactivity control over lifetime is achieved by axial displacement of movable seed zones without the use of poison rods in the embodiment illustrated. The seed is further characterized by a hydrogen-to-uranium-233 atom ratio in the range 10 to 200 and a uranium-233-to-thorium-232 atom ratio ranging from 0.012 to 0.200. The seed occupies from 10 to 35 percent of the core volume in the form of one or more individual islands or annuli. (NSA 26: 55130)

  16. Fast breeder reactor protection system

    DOEpatents

    van Erp, J.B.

    1973-10-01

    Reactor protection is provided for a liquid-metal-fast breeder reactor core by measuring the coolant outflow temperature from each of the subassemblies of the core. The outputs of the temperature sensors from a subassembly region of the core containing a plurality of subassemblies are combined in a logic circuit which develops a scram alarm if a predetermined number of the sensors indicate an over temperature condition. The coolant outflow from a single subassembly can be mixed with the coolant outflow from adjacent subassemblies prior to the temperature sensing to increase the sensitivity of the protection system to a single subassembly failure. Coherence between the sensors can be required to discriminate against noise signals. (Official Gazette)

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

    PubMed

    Hemelrijk, Charlotte K; Hildenbrandt, Hanno

    2011-01-01

    Flocks of birds are highly variable in shape in all contexts (while travelling, avoiding predation, wheeling above the roost). Particularly amazing in this respect are the aerial displays of huge flocks of starlings (Sturnus vulgaris) above the sleeping site at dawn. The causes of this variability are hardly known, however. Here we hypothesise that variability of shape increases when there are larger local differences in movement behaviour in the flock. We investigate this hypothesis with the help of a model of the self-organisation of travelling groups, called StarDisplay, since such a model has also increased our understanding of what causes the oblong shape of schools of fish. The flocking patterns in the model prove to resemble those of real birds, in particular of starlings and rock doves. As to shape, we measure the relative proportions of the flock in several ways, which either depend on the direction of movement or do not. We confirm that flock shape is usually more variable when local differences in movement in the flock are larger. This happens when a) flock size is larger, b) interacting partners are fewer, c) the flock turnings are stronger, and d) individuals roll into the turn. In contrast to our expectations, when variability of speed in the flock is higher, flock shape and the positions of members in the flock are more static. We explain this and indicate the adaptive value of low variability of speed and spatial restriction of interaction and develop testable hypotheses. PMID:21829627

  18. Automated assessment of footpad dermatitis in broiler chickens at the slaughter-line: evaluation and correspondence with human expert scores.

    PubMed

    Vanderhasselt, R F; Sprenger, M; Duchateau, L; Tuyttens, F A M

    2013-01-01

    Footpad dermatitis is increasingly used as an indicator of decreased broiler welfare, and automation of dermatitis monitoring potentially reduces the effort needed to monitor commercial flocks. In this study we evaluated a prototype system for the automatic assessment of footpad dermatitis in broiler chickens by comparing the automatic assessment with a human expert assessment. The expert aimed at selecting 2 times (different period) 20 broilers per footpad dermatitis category (5 categories in total), from 2 different flocks of 38-d-old broilers on an experimental farm. Two days later these broilers were transported to the slaughterhouse, where footpad dermatitis was assessed by the automatic system. Subsequently the footpads were reassessed by the same expert that had selected the birds. Automatic scores were only weakly correlated with scores given by the expert on-farm (r = 0.54) and at the slaughterhouse (r = 0.59). Manual evaluation of the photographs on which the automatic system based its scores revealed several errors. For 41.1% of the birds, the automatic system assessed only one of the footpads, whereas for 15.2% neither footpad was assessed. For 49.4% of the birds, scores were based on partially incorrectly identified areas. When data from such incomplete and obviously incorrect assessments were discarded, stronger correlations between automatic and expert scores were found (r = 0.68 and r = 0.74 for expert scores given on-farm and at-slaughter, respectively). Footpads that were missed by the automatic system were more likely to receive a high expert score at slaughter (P = 0.02). However, average flock scores did not differ greatly between automatic and expert scores. The prototype system for automatic dermatitis assessment needs to be improved on several points if it is to replace expert assessment of footpad dermatitis.

  19. Use of avilamycin for growth promotion and avilamycin-resistance among Enterococcus faecium from broilers in a matched case-control study in France.

    PubMed

    Chauvin, C; Gicquel-Bruneau, M; Perrin-Guyomard, A; Humbert, F; Salvat, G; Guillemot, D; Sanders, P

    2005-09-12

    We assessed the putative link between avilamycin-resistant Enterococcus faecium carriage and avilamycin consumption in broilers. As part of the French programme of monitoring for antimicrobial resistance, broilers sampled at slaughterhouse in 1999 and 2000 and carrying avilamycin-resistant E. faecium were matched by slaughterhouse, slaughter month and production type (free-range, standard, light) with control broilers carrying avilamycin-susceptible strains. History of antibiotics consumption (either for growth promotion or therapeutic purpose) in the broiler flocks sampled was collected from the monitoring programme and consumption of each antibiotic class was screened as a potential risk factor. Avilamycin was a risk factor for avilamycin-resistant E. faecium carriage: OR=2.3. PMID:16023523

  20. Comparison of early socialization practices used for litters of small-scale registered dog breeders and nonregistered dog breeders.

    PubMed

    Korbelik, Juraj; Rand, Jacquie S; Morton, John M

    2011-10-15

    OBJECTIVE-To compare early socialization practices between litters of breeders registered with the Canine Control Council (CCC) and litters of nonregistered breeders advertising puppies for sale in a local newspaper. DESIGN-Retrospective cohort study. Animals-80 litters of purebred and mixed-breed dogs from registered (n = 40) and non-registered (40) breeders. PROCEDURES-Registered breeders were randomly selected from the CCC website, and nonregistered breeders were randomly selected from a weekly advertising newspaper. The litter sold most recently by each breeder was then enrolled in the study. Information pertaining to socialization practices for each litter was obtained through a questionnaire administered over the telephone. RESULTS-Registered breeders generally had more breeding bitches and had more litters than did nonregistered breeders. Litters of registered breeders were more likely to have been socialized with adult dogs, people of different appearances, and various environmental stimuli, compared with litters of nonregistered breeders. Litters from registered breeders were also much less likely to have been the result of an unplanned pregnancy. CONCLUSIONS AND CLINICAL RELEVANCE-Among those breeders represented, litters of registered breeders received more socialization experience, compared with litters of nonregistered breeders. People purchasing puppies from nonregistered breeders should focus on socializing their puppies between the time of purchase and 14 weeks of age. Additional research is required to determine whether puppies from nonregistered breeders are at increased risk of behavioral problems and are therefore more likely to be relinquished to animal shelters or euthanized, relative to puppies from registered breeders. PMID:21985351

  1. Comparison of early socialization practices used for litters of small-scale registered dog breeders and nonregistered dog breeders.

    PubMed

    Korbelik, Juraj; Rand, Jacquie S; Morton, John M

    2011-10-15

    OBJECTIVE-To compare early socialization practices between litters of breeders registered with the Canine Control Council (CCC) and litters of nonregistered breeders advertising puppies for sale in a local newspaper. DESIGN-Retrospective cohort study. Animals-80 litters of purebred and mixed-breed dogs from registered (n = 40) and non-registered (40) breeders. PROCEDURES-Registered breeders were randomly selected from the CCC website, and nonregistered breeders were randomly selected from a weekly advertising newspaper. The litter sold most recently by each breeder was then enrolled in the study. Information pertaining to socialization practices for each litter was obtained through a questionnaire administered over the telephone. RESULTS-Registered breeders generally had more breeding bitches and had more litters than did nonregistered breeders. Litters of registered breeders were more likely to have been socialized with adult dogs, people of different appearances, and various environmental stimuli, compared with litters of nonregistered breeders. Litters from registered breeders were also much less likely to have been the result of an unplanned pregnancy. CONCLUSIONS AND CLINICAL RELEVANCE-Among those breeders represented, litters of registered breeders received more socialization experience, compared with litters of nonregistered breeders. People purchasing puppies from nonregistered breeders should focus on socializing their puppies between the time of purchase and 14 weeks of age. Additional research is required to determine whether puppies from nonregistered breeders are at increased risk of behavioral problems and are therefore more likely to be relinquished to animal shelters or euthanized, relative to puppies from registered breeders.

  2. Efficacy of feed additives against Campylobacter in live broilers during the entire rearing period.

    PubMed

    Guyard-Nicodème, M; Keita, A; Quesne, S; Amelot, M; Poezevara, T; Le Berre, B; Sánchez, J; Vesseur, P; Martín, Á; Medel, P; Chemaly, Marianne

    2016-02-01

    Poultry meat is the major source of human campylobacteriosis, the most frequently reported zoonosis in the EU. The prevalence of Campylobacter colonization in European broiler flocks is 71%. Despite considerable efforts, there is still no effective strategy available to prevent or reduce Campylobacter colonization in broilers. This study tested a wide variety of feed additives to reduce Campylobacter shedding in primary poultry production. Twelve additives containing organic or fatty acids, monoglycerides, plant extracts, prebiotics, or probiotics were tested. For each additive, broilers contaminated with Campylobacter jejuni were fed with an additive free diet (control group) or with a supplemented diet (treated group) and Campylobacter loads compared at three sampling times. No treatment was able to prevent broiler colonization by Campylobacter, and there was a high degree of variation in contamination among the birds. At 14 d of age, eight treatments significantly decreased the colonization level compared to the control group by a maximum of 2 log10 CFU/g. At 35 d of age, three of these treatments still had a significant effect with a maximum reduction of 1.88 log10 CFU/g for a probiotic. At 42 d of age, only one short-chain fatty acid was still significantly efficient with a mean reduction over 2 log10 CFU/g. In addition, a probiotic and a prebiotic-like compound significantly decreased the contamination by a maximum of 3 log10 CFU/g, only at the 42-d sampling period. This study gives promising results regarding the use of feed additives to reduce Campylobacter infection in flocks. Nevertheless, a global approach, combining intervention measures at the different steps of the broiler meat production chain could have a greater impact on the reduction of public health risk. PMID:26706356

  3. Is allicin able to reduce Campylobacter jejuni colonization in broilers when added to drinking water?

    PubMed

    Robyn, J; Rasschaert, G; Hermans, D; Pasmans, F; Heyndrickx, M

    2013-05-01

    Reducing Campylobacter shedding on the farm could result in a reduction of the number of human campylobacteriosis cases. In this study, we first investigated if allicin, allyl disulfide, and garlic oil extract were able to either prevent C. jejuni growth or kill C. jejuni in vitro. Allyl disulfide and garlic oil extract reduced C. jejuni numbers in vitro below a detectable level at a concentration of 50 mg/kg (no lower concentrations were tested), whereas allicin reduced C. jejuni numbers below a detectable level at a concentration as low as 7.5 mg/kg. In further experiments we screened for the anti-C. jejuni activity of allicin in a fermentation system closely mimicking the broiler cecal environment using cecal microbiota and mucus isolated from C. jejuni-free broilers. During these fermentation experiments, allicin reduced C. jejuni numbers below a detectable level after 24 h at a concentration of 50 mg/kg. In contrast, 25 mg/kg of allicin killed C. jejuni in the first 28 h of incubation, but anti-C. jejuni activity was lost after 48 h of incubation, probably due to the presence of mucin in the growth medium. This had been confirmed in fermentation experiments in the presence of broiler cecal mucus. Based on these results, we performed an in vivo experiment to assess the prevention or reduction of cecal C. jejuni colonization in broiler chickens when allicin was added to drinking water. We demonstrated that allicin in drinking water did not have a statistically significant effect on cecal C. jejuni colonization in broilers. It was assumed, based on in vitro experiments, that the activity of allicin was thwarted by the presence of mucin-containing mucus. Despite promising in vitro results, allicin was not capable of statistically influencing C. jejuni colonization in a broiler flock, although a trend toward lower cecal C. jejuni numbers in allicin-treated broilers was observed.

  4. Prevalence of Antibiotic-Resistant Fecal Escherichia coli Isolates from Penned Broiler and Scavenging Local Chickens in Arusha, Tanzania.

    PubMed

    Rugumisa, Bernadether T; Call, Douglas R; Mwanyika, Gaspary O; Mrutu, Rehema I; Luanda, Catherine M; Lyimo, Beatus M; Subbiah, Murugan; Buza, Joram J

    2016-08-01

    We compared the prevalence of antibiotic-resistant Escherichia coli isolates from household-level producers of broiler (commercial source breeds) and local chickens in the Arusha District of Tanzania. Households were composed of a single dwelling or residence with independent, penned broiler flocks. Free-range, scavenging chickens were mixed breed and loosely associated with individual households. A total of 1,800 E. coli isolates (1,200 from broiler and 600 from scavenging local chickens) from 75 chickens were tested for their susceptibility against 11 antibiotics by using breakpoint assays. Isolates from broiler chickens harbored a higher prevalence of antibiotic-resistant E. coli relative to scavenging local chickens, including sulfamethoxazole (80.3 versus 34%), followed by trimethoprim (69.3 versus 27.7%), tetracycline (56.8 versus 20%), streptomycin (52.7 versus 24.7%), amoxicillin (49.6 versus 17%), ampicillin (49.1 versus 16.8%), ciprofloxacin (21.9 versus 1.7%), and chloramphenicol (1.5 versus 1.2%). Except for resistance to chloramphenicol, scavenging local chickens harbored fewer resistant E. coli isolates (P < 0.05). Broiler chickens harbored more isolates that were resistant to ≥7 antibiotics (P < 0.05). The higher prevalence of antibiotic-resistant E. coli from broiler chickens correlated with the reported therapeutic and prophylactic use of antibiotics in this poultry population. We suggest that improved biosecurity measures and increased vaccination efforts would reduce reliance on antibiotics by these households. PMID:27497131

  5. Prevalence of Antibiotic-Resistant Fecal Escherichia coli Isolates from Penned Broiler and Scavenging Local Chickens in Arusha, Tanzania.

    PubMed

    Rugumisa, Bernadether T; Call, Douglas R; Mwanyika, Gaspary O; Mrutu, Rehema I; Luanda, Catherine M; Lyimo, Beatus M; Subbiah, Murugan; Buza, Joram J

    2016-08-01

    We compared the prevalence of antibiotic-resistant Escherichia coli isolates from household-level producers of broiler (commercial source breeds) and local chickens in the Arusha District of Tanzania. Households were composed of a single dwelling or residence with independent, penned broiler flocks. Free-range, scavenging chickens were mixed breed and loosely associated with individual households. A total of 1,800 E. coli isolates (1,200 from broiler and 600 from scavenging local chickens) from 75 chickens were tested for their susceptibility against 11 antibiotics by using breakpoint assays. Isolates from broiler chickens harbored a higher prevalence of antibiotic-resistant E. coli relative to scavenging local chickens, including sulfamethoxazole (80.3 versus 34%), followed by trimethoprim (69.3 versus 27.7%), tetracycline (56.8 versus 20%), streptomycin (52.7 versus 24.7%), amoxicillin (49.6 versus 17%), ampicillin (49.1 versus 16.8%), ciprofloxacin (21.9 versus 1.7%), and chloramphenicol (1.5 versus 1.2%). Except for resistance to chloramphenicol, scavenging local chickens harbored fewer resistant E. coli isolates (P < 0.05). Broiler chickens harbored more isolates that were resistant to ≥7 antibiotics (P < 0.05). The higher prevalence of antibiotic-resistant E. coli from broiler chickens correlated with the reported therapeutic and prophylactic use of antibiotics in this poultry population. We suggest that improved biosecurity measures and increased vaccination efforts would reduce reliance on antibiotics by these households.

  6. Presence of antimicrobial resistance in coliform bacteria from hatching broiler eggs with emphasis on ESBL/AmpC-producing bacteria.

    PubMed

    Mezhoud, H; Chantziaras, I; Iguer-Ouada, M; Moula, N; Garmyn, A; Martel, A; Touati, A; Smet, A; Haesebrouck, F; Boyen, F

    2016-08-01

    Antimicrobial resistance is recognized as one of the most important global health challenges. Broilers are an important reservoir of antimicrobial resistant bacteria in general and, more particularly, extended-spectrum β-lactamases (ESBL)/AmpC-producing Enterobacteriaceae. Since contamination of 1-day-old chicks is a potential risk factor for the introduction of antimicrobial resistant Enterobacteriaceae in the broiler production chain, the presence of antimicrobial resistant coliform bacteria in broiler hatching eggs was explored in the present study. Samples from 186 hatching eggs, collected from 11 broiler breeder farms, were inoculated on MacConkey agar with or without ceftiofur and investigated for the presence of antimicrobial resistant lactose-positive Enterobacteriaceae, particularly, ESBL/AmpC-producers. Escherichia coli and Enterobacter cloacae were obtained from the eggshells in 10 out of 11 (10/11) sampled farms. The majority of the isolates were recovered from crushed eggshells after external decontamination suggesting that these bacteria are concealed from the disinfectants in the egg shell pores. Antimicrobial resistance testing revealed that approximately 30% of the isolates showed resistance to ampicillin, tetracycline, trimethoprim and sulphonamides, while the majority of isolates were susceptible to amoxicillin-clavulanic acid, nitrofurantoin, aminoglycosides, florfenicol, neomycin and apramycin. Resistance to extended-spectrum cephalosporins was detected in eight Enterobacteriaceae isolates from five different broiler breeder farms. The ESBL phenotype was confirmed by the double disk synergy test and blaSHV-12, blaTEM-52 and blaACT-39 resistance genes were detected by PCR. This report is the first to present broiler hatching eggs as carriers and a potential source of ESBL/AmpC-producing Enterobacteriaceae for broiler chicks.

  7. Serological and molecular detection of chicken anaemia virus in Iranian poultry flocks.

    PubMed

    Gholami-Ahangaran, Majid

    2015-01-01

    Despite chicken being the main natural host for chicken anaemia virus (CAV), other birds may be infected by this virus too. In this study we examined chickens, turkeys, and quails for serological and molecular detection of CAV in Iran. For this study, we used 375 sera and thymus samples from broiler chickens, 100 sera and blood samples from turkeys, and 250 thymus samples from quails. The sample were collected from all over Iran between 2009 and 2010. Serum samples were examined using ELISA. DNA was extracted from thymus and blood samples and was analysed for the presence of the VP2 gene of CAV by polymerase chain reaction. Results showed that 69.07% of chickens were positive for antibody to CAV. In chickens, 58.4% were positive for CAV VP2 gene. The prevalence of CAV infection in quails was 15%, based on CAV VP2 gene detection. In turkey flocks, all turkeys (100%) were negative with respect to detection of VP2 CAV gene and CAV antibodies. It was concluded that, for the span of the time considered in this study, CAV has circulated in broiler chickens and quails throughout Iran.

  8. The toxicological impacts of the Fusarium mycotoxin, deoxynivalenol, in poultry flocks with special reference to immunotoxicity.

    PubMed

    Awad, Wageha; Ghareeb, Khaled; Böhm, Josef; Zentek, Jürgen

    2013-04-29

    Deoxynivalenol (DON) is a common Fusarium toxin in poultry feed. Chickens are more resistant to the adverse impacts of deoxynivalenol (DON) compared to other species. In general, the acute form of DON mycotoxicosis rarely occurs in poultry flocks under normal conditions. However, if diets contain low levels of DON (less than 5 mg DON/kg diet), lower productivity, impaired immunity and higher susceptibility to infectious diseases can occur. The molecular mechanism of action of DON has not been completely understood. A significant influence of DON in chickens is the impairment of immunological functions. It was known that low doses of DON elevated the serum IgA levels and affected both cell-mediated and humoral immunity in animals. DON is shown to suppress the antibody response to infectious bronchitis vaccine (IBV) and to Newcastle disease virus (NDV) in broilers (10 mg DON/kg feed) and laying hens (3.5 to 14 mg of DON/kg feed), respectively. Moreover, DON (10 mg DON/kg feed) decreased tumor necrosis factor alpha (TNF-α) in the plasma of broilers. DON can severely affect the immune system and, due to its negative impact on performance and productivity, can eventually result in high economic losses to poultry producers. The present review highlights the impacts of DON intoxication on cell mediated immunity, humoral immunity, gut immunity, immune organs and pro-inflammatory cytokines in chickens.

  9. Breeder reactors: A renewable energy source

    NASA Astrophysics Data System (ADS)

    Cohen, Bernard L.

    1983-01-01

    Based on a cost analysis of uranium extracted from seawater, it is concluded that the world's energy requirements for the next 5 billion years can be met by breeder reactors with no price increase due to fuel costs.(AIP)

  10. Performance of an animal-based test of thirst in commercial broiler chicken farms.

    PubMed

    Vanderhasselt, R F; Goethals, K; Buijs, S; Federici, J F; Sans, E C O; Molento, C F M; Duchateau, L; Tuyttens, F A M

    2014-06-01

    Animal-based measures of thirst are currently absent from animal welfare monitoring schemes due to the lack of a well-validated indicator applicable for on-farm use. In the present study, an on-farm test based on voluntary water consumption from an unfamiliar open drinker was validated in a (semi-)commercial setting. To investigate the effect of thirst on water consumption, we subjected 4 flocks of 1,500 broilers to either 0 or 12 h of water deprivation and subsequently measured the amount of water that small subgroups consumed after the deprivation period (first experiment). Broilers that were water deprived before the test drank more than control broilers (P < 0.001). In a second experiment, a similar test was performed using 20 commercial broiler flocks in Belgium and Brazil. After a pretreatment water consumption test, the birds were subjected to 0 or 6 h of water deprivation, and a posttreatment water consumption test was conducted. Only in Brazil, deprived birds drank significantly more than controls in the posttreatment water consumption test (P < 0.001). A tendency for a difference was found in Belgium (P = 0.083). Pre- and posttreatment water consumption was higher in Brazil than in Belgium (P < 0.001). Stocking density and temperature influenced, respectively, the pretreatment and the control's posttreatment water consumption in Brazil, but not in Belgium. These results indicate that the water consumption test is sufficiently sensitive to discriminate between control and 12 h deprived flocks, and in Brazil even between control and 6 h deprived birds. The location of the test within the house did not affect the amount of water consumed in either experiment, suggesting that this variable does not have to be standardized. However, the amount of water consumed by broilers able to drink freely for a long period depended on indoor climatic variables (in Brazil only) and possibly genotype. This suggests that these variables need to be considered when

  11. Transgenerational epigenetic effects on innate immunity in broilers: an underestimated field to be explored?

    PubMed

    Berghof, T V L; Parmentier, H K; Lammers, A

    2013-11-01

    Transgenerational epigenetics is becoming more and more important for understanding the variation of physiological responses of individuals to the environment and the inheritance of these responses based on all mechanisms other than the actual DNA nucleotide sequence. Transgenerational epigenetics is the phenomenon that the information of the environment of (usually) a female animal is translated into memory-like responses preparing the offspring. As a consequence, individuals of the next generation may show different phenotypic traits depending whether their mothers were kept under different environmental conditions. This may result in either positive or negative effects on the next-generation individuals, which is different from individuals from mothers that have been kept in a different environment. Transgenerational epigenetic effects have been proposed and indicated for specific immune (T cell and antibody) responses (especially in mammals, but also in birds) and innate immunity (nonvertebrates), but surprisingly very little is known of transgenerational effects on innate immunity in chickens. Given the short lifespan of the chicken and therefore the likely dependence of chicken on innate immune mechanisms, more attention should be given to this arm of immunity and mechanisms of inheritance including transgenerational effects that can be initiated in the breeder generation. In addition, it is becoming evident that innate immunity also underlies metabolic disorders in broilers. In the current paper, we will argue that although very little is known of transgenerational effects of innate immunity in poultry, more attention should be given to this type of study. We will illustrate examples of transgenerational epigenetics, and finally propose strategies that should reveal the presence of transgenerational epigenetic effects on innate immunity in chickens and strategies to modulate breeder birds such that these effects positively affect innate immunity of broilers

  12. Persistence of vancomycin resistance in multiple clones of Enterococcus faecium isolated from Danish broilers 15 years after the ban of avoparcin.

    PubMed

    Bortolaia, Valeria; Mander, Manuela; Jensen, Lars B; Olsen, John E; Guardabassi, Luca

    2015-05-01

    The occurrence and diversity of vancomycin-resistant Enterococcus faecium (VREF) were investigated in 100 Danish broiler flocks 15 years after the avoparcin ban. VREF occurred in 47 flocks at low fecal concentrations detectable only by selective enrichment. Vancomycin resistance was prevalently associated with a transferable nontypeable plasmid lineage occurring in multiple E. faecium clones. Coselection of sequence type 842 by tetracycline use only partly explained the persistence of vancomycin resistance in the absence of detectable plasmid coresistance and toxin-antitoxin systems. PMID:25712360

  13. A longitudinal study to assess the persistence of vancomycin-resistant Enterococcus faecium (VREF) on an intensive broiler farm in the United Kingdom.

    PubMed

    Garcia-Migura, Lourdes; Liebana, Ernesto; Jensen, Lars Bogø; Barnes, Simon; Pleydell, Eve

    2007-10-01

    Seven years after the ban of avoparcin, VREF could still be isolated within sectors of the UK broiler industry. The aim of this study was to assess whether there is a carryover of VREF between consecutive flocks of birds, to conduct a preliminary investigation of possible routes of entry of VREF into broiler houses and to follow the dynamics of VREF shed by growing birds. A series of nine visits were made to two of six houses on a conventional broiler farm. A total of 343 vanA VREF were recovered from environmental (95/843) and faecal (248/416) samples. Significant differences were observed in the carryover of VREF between pre- and postcohort postcleaning and disinfection visits (RR 0.57, P=0.006). Ninety-nine percent of the VREF isolates were resistant to more than five antimicrobials, with 42 isolates (n=49) positive for erm(B) and 32 (n=40) for vat(E). Pulsed field gel electrophoresis (PFGE) typing identified 50 PFGE types within 15 different PFGE clusters of 90% similarity, demonstrating a high level of genetic diversity within VREF populations from epidemiologically related broiler flocks and broiler houses. Further characterization of Tn1546 from different clones showed a low diversity of Tn-types, suggesting horizontal transfer of resistance determinants between different genetic clones. Thus, this study does not only show the persistence of VREF but also of multi-drug resistant lineages of VREF. PMID:17825067

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

    PubMed

    Beauchamp, Guy

    2004-05-22

    Adaptive hypotheses for the evolution of flocking in birds have usually focused on predation avoidance or foraging enhancement. It still remains unclear to what extent each factor has contributed to the evolution of flocking. If predation avoidance were the sole factor involved, flocking should not be prevalent when predation is relaxed. I examined flocking tendencies along with mean and maximum flock size in species living on islands where predation risk is either absent or negligible and then compared these results with matched counterparts on the mainland. The dataset consisted of 46 pairs of species from 22 different islands across the world. The tendency to flock was retained on islands in most species, but in pairs with dissimilar flocking tendencies, island species were less likely to flock. Mean and maximum flock size were smaller on islands than on the mainland. Potential confounding factors such as population density, nest predation, habitat type, food type and body mass failed to account for the results. The results suggest that predation is a significant factor in the evolution of flocking in birds. Nevertheless, predation and other factors, such as foraging enhancement, probably act together to maintain the trait in most species. PMID:15293857

  15. Role of projection in the control of bird flocks.

    PubMed

    Pearce, Daniel J G; Miller, Adam M; Rowlands, George; Turner, Matthew S

    2014-07-22

    Swarming is a conspicuous behavioral trait observed in bird flocks, fish shoals, insect swarms, and mammal herds. It is thought to improve collective awareness and offer protection from predators. Many current models involve the hypothesis that information coordinating motion is exchanged among neighbors. We argue that such local interactions alone are insufficient to explain the organization of large flocks of birds and that the mechanism for the exchange of long-range information necessary to control their density remains unknown. We show that large flocks self-organize to the maximum density at which a typical individual still can see out of the flock in many directions. Such flocks are marginally opaque--an external observer also still can see a substantial fraction of sky through the flock. Although this seems intuitive, we show it need not be the case; flocks might easily be highly diffuse or entirely opaque. The emergence of marginal opacity strongly constrains how individuals interact with one another within large swarms. It also provides a mechanism for global interactions: an individual can respond to the projection of the flock that it sees. This provides for faster information transfer and hence rapid flock dynamics, another advantage over local models. From a behavioral perspective, it optimizes the information available to each bird while maintaining the protection of a dense, coherent flock. PMID:25002501

  16. A Flocking Based algorithm for Document Clustering Analysis

    SciTech Connect

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

    2006-01-01

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

  17. Is the species flock concept operational? The Antarctic shelf case.

    PubMed

    Lecointre, Guillaume; Améziane, Nadia; Boisselier, Marie-Catherine; Bonillo, Céline; Busson, Frédéric; Causse, Romain; Chenuil, Anne; Couloux, Arnaud; Coutanceau, Jean-Pierre; Cruaud, Corinne; d'Acoz, Cédric d'Udekem; De Ridder, Chantal; Denys, Gael; Dettaï, Agnès; Duhamel, Guy; Eléaume, Marc; Féral, Jean-Pierre; Gallut, Cyril; Havermans, Charlotte; Held, Christoph; Hemery, Lenaïg; Lautrédou, Anne-Claire; Martin, Patrick; Ozouf-Costaz, Catherine; Pierrat, Benjamin; Pruvost, Patrice; Puillandre, Nicolas; Samadi, Sarah; Saucède, Thomas; Schubart, Christoph; David, Bruno

    2013-01-01

    There has been a significant body of literature on species flock definition but not so much about practical means to appraise them. We here apply the five criteria of Eastman and McCune for detecting species flocks in four taxonomic components of the benthic fauna of the Antarctic shelf: teleost fishes, crinoids (feather stars), echinoids (sea urchins) and crustacean arthropods. Practical limitations led us to prioritize the three historical criteria (endemicity, monophyly, species richness) over the two ecological ones (ecological diversity and habitat dominance). We propose a new protocol which includes an iterative fine-tuning of the monophyly and endemicity criteria in order to discover unsuspected flocks. As a result nine « full » species flocks (fulfilling the five criteria) are briefly described. Eight other flocks fit the three historical criteria but need to be further investigated from the ecological point of view (here called "core flocks"). The approach also shows that some candidate taxonomic components are no species flocks at all. The present study contradicts the paradigm that marine species flocks are rare. The hypothesis according to which the Antarctic shelf acts as a species flocks generator is supported, and the approach indicates paths for further ecological studies and may serve as a starting point to investigate the processes leading to flock-like patterning of biodiversity.

  18. Misinformed leaders lose influence over pigeon flocks.

    PubMed

    Watts, Isobel; Nagy, Máté; Burt de Perera, Theresa; Biro, Dora

    2016-09-01

    In animal groups where certain individuals have disproportionate influence over collective decisions, the whole group's performance may suffer if these individuals possess inaccurate information. Whether in such situations leaders can be replaced in their roles by better-informed group mates represents an important question in understanding the adaptive consequences of collective decision-making. Here, we use a clock-shifting procedure to predictably manipulate the directional error in navigational information possessed by established leaders within hierarchically structured flocks of homing pigeons (Columba livia). We demonstrate that in the majority of cases when leaders hold inaccurate information they lose their influence over the flock. In these cases, inaccurate information is filtered out through the rearrangement of hierarchical positions, preventing errors by former leaders from propagating down the hierarchy. Our study demonstrates that flexible decision-making structures can be valuable in situations where 'bad' information is introduced by otherwise influential individuals. PMID:27624797

  19. Misinformed leaders lose influence over pigeon flocks.

    PubMed

    Watts, Isobel; Nagy, Máté; Burt de Perera, Theresa; Biro, Dora

    2016-09-01

    In animal groups where certain individuals have disproportionate influence over collective decisions, the whole group's performance may suffer if these individuals possess inaccurate information. Whether in such situations leaders can be replaced in their roles by better-informed group mates represents an important question in understanding the adaptive consequences of collective decision-making. Here, we use a clock-shifting procedure to predictably manipulate the directional error in navigational information possessed by established leaders within hierarchically structured flocks of homing pigeons (Columba livia). We demonstrate that in the majority of cases when leaders hold inaccurate information they lose their influence over the flock. In these cases, inaccurate information is filtered out through the rearrangement of hierarchical positions, preventing errors by former leaders from propagating down the hierarchy. Our study demonstrates that flexible decision-making structures can be valuable in situations where 'bad' information is introduced by otherwise influential individuals.

  20. Flocking algorithm for autonomous flying robots.

    PubMed

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

    2014-06-01

    Animal swarms displaying a variety of typical flocking patterns would not exist without the underlying safe, optimal and stable dynamics of the individuals. The emergence of these universal patterns can be efficiently reconstructed with agent-based models. If we want to reproduce these patterns with artificial systems, such as autonomous aerial robots, agent-based models can also be used in their control algorithms. However, finding the proper algorithms and thus understanding the essential characteristics of the emergent collective behaviour requires thorough and realistic modeling of the robot and also the environment. In this paper, we first present an abstract mathematical model of an autonomous flying robot. The model takes into account several realistic features, such as time delay and locality of communication, inaccuracy of the on-board sensors and inertial effects. We present two decentralized control algorithms. One is based on a simple self-propelled flocking model of animal collective motion, the other is a collective target tracking algorithm. Both algorithms contain a viscous friction-like term, which aligns the velocities of neighbouring agents parallel to each other. We show that this term can be essential for reducing the inherent instabilities of such a noisy and delayed realistic system. We discuss simulation results on the stability of the control algorithms, and perform real experiments to show the applicability of the algorithms on a group of autonomous quadcopters. In our case, bio-inspiration works in two ways. On the one hand, the whole idea of trying to build and control a swarm of robots comes from the observation that birds tend to flock to optimize their behaviour as a group. On the other hand, by using a realistic simulation framework and studying the group behaviour of autonomous robots we can learn about the major factors influencing the flight of bird flocks. PMID:24852272

  1. Flocking algorithm for autonomous flying robots.

    PubMed

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

    2014-06-01

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

  2. Potential environmental benefits of prospective genetic changes in broiler traits.

    PubMed

    Leinonen, I; Williams, A G; Kyriazakis, I

    2016-02-01

    A system approach-based Life Cycle Assessment (LCA) framework, combined with a simple mechanistic model of bird energy balance was used to predict the potential effects of 15 y prospective broiler breeding on the environmental impacts of the standard UK broiler production system. The year 2014 Ross 308 genotype was used as a baseline, and a future scenario was specified from rates of genetic improvement predicted by the industry. The scenario included changes in the traits of growth rate (reducing the time to reach a target weight 2.05 kg from 34 d to 27 d), body lipid content, carcass yield, mortality and the number of chicks produced by a breeder hen. Diet composition was adjusted in order to accommodate the future nutrient requirements of the birds following the genetic change. The results showed that predicted changes in biological performance due to selective breeding could lead to reduced environmental impacts of the broiler production chain, most notably in the Eutrophication Potential (by 12%), Acidification Potential (by 10%) and Abiotic Resource Use (by 9%) and Global Warming Potential (by 9%). These reductions were mainly caused by the reduced maintenance energy requirement and thus lower feed intake, resulting from the shorter production cycle, together with the increased carcass yield. However, some environmental benefits were limited by the required changes in feed composition (e.g., increased inclusion of soy meal and vegetable oil) as a result of the changes in bird nutrient requirements. This study is the first one aiming to link the mechanistic animal modeling approach to predicted genetic changes in order to produce quantitative estimates of the future environmental impacts of broiler production. Although a more detailed understanding on the mechanisms of the potential changes in bird performance and their consequences on feeding and husbandry would be still be needed, the modeling framework produced in this study provides a starting point for

  3. Potential environmental benefits of prospective genetic changes in broiler traits.

    PubMed

    Leinonen, I; Williams, A G; Kyriazakis, I

    2016-02-01

    A system approach-based Life Cycle Assessment (LCA) framework, combined with a simple mechanistic model of bird energy balance was used to predict the potential effects of 15 y prospective broiler breeding on the environmental impacts of the standard UK broiler production system. The year 2014 Ross 308 genotype was used as a baseline, and a future scenario was specified from rates of genetic improvement predicted by the industry. The scenario included changes in the traits of growth rate (reducing the time to reach a target weight 2.05 kg from 34 d to 27 d), body lipid content, carcass yield, mortality and the number of chicks produced by a breeder hen. Diet composition was adjusted in order to accommodate the future nutrient requirements of the birds following the genetic change. The results showed that predicted changes in biological performance due to selective breeding could lead to reduced environmental impacts of the broiler production chain, most notably in the Eutrophication Potential (by 12%), Acidification Potential (by 10%) and Abiotic Resource Use (by 9%) and Global Warming Potential (by 9%). These reductions were mainly caused by the reduced maintenance energy requirement and thus lower feed intake, resulting from the shorter production cycle, together with the increased carcass yield. However, some environmental benefits were limited by the required changes in feed composition (e.g., increased inclusion of soy meal and vegetable oil) as a result of the changes in bird nutrient requirements. This study is the first one aiming to link the mechanistic animal modeling approach to predicted genetic changes in order to produce quantitative estimates of the future environmental impacts of broiler production. Although a more detailed understanding on the mechanisms of the potential changes in bird performance and their consequences on feeding and husbandry would be still be needed, the modeling framework produced in this study provides a starting point for

  4. Maternal energy and protein affect subsequent growth performance, carcass yield, and meat color in Chinese Yellow broilers.

    PubMed

    Zhu, C; Jiang, Z Y; Jiang, S Q; Zhou, G L; Lin, Y C; Chen, F; Hong, P

    2012-08-01

    This experiment was carried out to investigate effects of maternal ME and CP levels on growth performance, carcass traits, and meat quality of broiler offspring. A total of 1,134 thirty-week-old Chinese Yellow broiler breeders was randomly assigned to 3 dietary ME levels (11.09, 11.51, and 11.92 MJ/kg) and 3 CP levels (15.5, 16.5, and 17.5%) in a 3×3 factorial arrangement. Each dietary treatment had 6 replicates with 21 hens per replicate. At 39 wk of age, 30 settable eggs per replicate were selected for hatching. All broiler offspring were fed the same diets. There were significant ME×CP interactions in egg CP and ether extract (EE) contents, BW at d 1, 22 to 42 d ADG, ADFI during 1 to 21 d and 43 to 63 d, shear force, plasma albumin, cholesterol, and triglycerides contents of broiler offspring. Dietary ME at 11.92 MJ/kg increased average egg weight, egg EE content, and broiler 1-d-old BW compared with 11.09 MJ/kg group at 16.5%, 15.5%, and 17.5% CP levels, respectively (P<0.05). Maternal 11.51 and 11.92 MJ/kg of ME increased 1 to 21-d ADFI, and 11.51 MJ/kg of ME decreased lightness (L*) value of broiler offspring compared with 11.09 MJ/kg group at 17.5 and 16.5% CP levels, respectively (P<0.05). Broiler breeder dietary CP at 17.5% decreased egg EE content, increased average egg weight, egg CP content, BW at d 1, and 1 to 21-d ADFI of broiler offspring compared with 15.5% CP group at 11.92 MJ/kg of ME level (P<0.05). Maternal dietary 15.5% CP increased dressing percentage and decreased yellowness (b*) value of broiler offspring compared with 16.5% and 17.5% CP groups at 11.51 MJ/kg of ME level, respectively (P<0.05). Collectively, the results indicate that maternal diets composed of 11.51 to 11.92 MJ/kg of ME and 17.5% CP at 39 wk of age increased growth performance during 1 to 21 d in Chinese Yellow broiler, whereas 11.51 MJ/kg of ME and 15.5% CP improved carcass dressing percentage and meat color of their offspring. PMID:22802180

  5. Model flocks in a steady vortical flow.

    PubMed

    Baggaley, A W

    2015-05-01

    We modify the standard Vicsek model to clearly distinguish between intrinsic noise due to imperfect alignment between organisms and extrinsic noise due to fluid motion. We then consider the effect of a steady vortical flow, the Taylor-Green vortex, on the dynamics of the flock, for various flow speeds, with a fixed intrinsic particle speed. We pay particular attention to the morphology of the flow, and quantify its filamentarity. Strikingly, above a critical flow speed there is a pronounced increase in the filamentarity of the flock, when compared to the zero-flow case. This is due to the fact that particles appear confined to areas of low vorticity; a familiar phenomena, commonly seen in the clustering of inertial particles in vortical flows. Hence, the cooperative motion of the particles gives them an effective inertia, which is seen to have a profound effect on the morphology of the flock, in the presence of external fluid motion. Finally, we investigate the angle between the flow and the particles direction of movement and find it follows a power-law distribution. PMID:26066260

  6. Temperature during the last week of incubation. I. Effects on hatching pattern and broiler chicken embryonic organ development.

    PubMed

    Maatjens, C M; van Roovert-Reijrink, I A M; Engel, B; van der Pol, C W; Kemp, B; van den Brand, H

    2016-04-01

    We investigated the effects of an eggshell temperature (EST) of 35.6, 36.7, 37.8, and 38.9°C applied from d of incubation (E) 15, E17, and E19 on hatching pattern and embryonic organ development. A total of 2,850 first-grade eggs of a 43-week-old Ross 308 broiler breeder flock were incubated at an EST of 37.8°C until E15. From E15, E17, or E19 onward, eggs were incubated at an EST of 35.6, 36.7, 37.8, or 38.9°C. Moment of internal pipping (IP), external pipping (EP), and hatch was determined, and organ development was measured at E15, E17, E19, IP, EP, and hatch. A lower EST extended incubation duration compared to a higher EST. The lower incubation duration was mainly caused by the extended time until IP, whereas time between IP and hatch hardly varied between treatments. Relative heart weight was affected by EST already from 2 d after the start of EST treatment on E15, and effects became more pronounced at longer exposure time to various EST treatments. At hatch, the largest difference in relative heart weight was found between an EST of 35.6 and 38.9°C started at E15 (Δ=64.4%). From E17 onward, EST affected yolk-free body mass (YFBM) and relative stomach weight, where a lower EST resulted in a lower YFBM and relative stomach weight before IP and a higher YFBM and relative stomach weight after IP. From E19 onward, a lower EST resulted in a higher relative liver and spleen weight regardless of start time of treatment. Yolk weight and relative intestine weight were not affected by EST before and at E19, but a higher EST resulted in a higher yolk weight and lower relative intestine weight from IP onward. Based on the higher YFBM and higher relative organ growth found at hatch, we concluded that an EST lower than 37.8°C from E15 onward appears to be beneficial for optimal embryo development. PMID:26787926

  7. Feather conditions and clinical scores as indicators of broilers welfare at the slaughterhouse.

    PubMed

    Saraiva, S; Saraiva, C; Stilwell, G

    2016-08-01

    The objective of this study was to evaluate the welfare of 64 different broiler farms on the basis of feather conditions and clinical scores measures collected at the slaughterhouse. A 3-point scale (0, 1 or 2) was used to classify dirty feathers, footpad dermatitis and hock burns measures, and a 2-point scale (present or absent) was used to classify breast burns, breast blisters and breast ulcer measures. Flocks were allocated into three body weight (BW) classes (A, B, C): class A (light) ≥1.43 and ≤1.68kg, class B (medium) ≥1.69 and ≤1.93kg; class C (heavy) ≥1.94 and ≤2.41kg. The absence of hock burns was more common in class A, while mild hock burns was more common in class B flocks. Breast ulcer was observed in class C flocks. The association observed for mild hock burns, breast burns and severe footpad dermatitis can indicate a simultaneous occurrence of these painful lesions. Very dirty feathers and severe footpad dermatitis relationship suggest litter humidity to be the common underlying cause. In conclusion, it was shown that clinical indicators can be used at the slaughterhouse to identify welfare problems. In the studied flocks, footpad dermatitis, feather conditions and hock burns were the main restrictions for good welfare and should be considered significant welfare indicators of the on-farm rearing conditions. PMID:27473978

  8. Are mixed-species bird flocks stable through two decades?

    PubMed

    Martínez, Ari E; Gomez, Juan P

    2013-03-01

    The stability of tropical systems has been hypothesized to explain the evolution of complex behavioral interactions among species. We evaluate the degree to which one highly evolved social system, mixed-species flocks, are stable in space and time in French Guiana, where flocks were characterized 17 years apart. These flocks are led by alarm-calling "sentinels," which may benefit from food flushed by other "beater" species. Using null models, we found that flock roost sites, home range overlap, and composition were more similar than expected by chance; home ranges were nearly identical between the two time periods. Such extremely stable conditions may be essential for the evolution and maintenance of the sentinel-beater system that appears to characterize some flocks. These results may reflect an evolutionarily stable strategy among potentially interdependent species within mixed-species flocks, where home ranges contribute to stability by being far larger than the most common local disturbances in the forest. PMID:23448892

  9. Nylon flocked swab severely reduces Hexagon Obti sensibility.

    PubMed

    Frippiat, Christophe; De Roy, Gilbert; Fontaine, Louis-Marie; Dognaux, Sophie; Noel, Fabrice; Heudt, Laeticia; Lepot, Laurent

    2015-02-01

    Hexagon Obti immunological blood test and flocked swab are widely used in forensic laboratories. Nevertheless, up to now, no compatibility tests have been published between sampling with the ethylene oxide treated flocked swab and the Hexagon Obti blood detection strip. In this study, we investigated this compatibility. Our work shows that sampling with ethylene oxide treated flocked swab reduces by a factor of at least 100 the detection threshold of blood using the Hexagon Obti immunological test. PMID:25575014

  10. Virus-neutralizing antibody titers against 8 avian adenovirus serotypes in breeder hens in Georgia by a microneutralization procedure.

    PubMed

    Grimes, T M; Culver, D H; King, D J

    1977-01-01

    Serums from 16 chicken-breeder flocks in Georgia were tested for virus-neutralizing antibody to 8 serotypes of avian adenovirus. Titers to all 8 serotypes were demonstrated in 8 of the flocks, titers to 7 in 6, and titers to fewer than 7 in the other 2 flocks. Although titers were high overall to some serotypes (types 2 and 8) and low to others (types 1, 4, and 5), with statistically significant differences between many titers, the data were difficult to interpret because of possible heterotypic responses of chickens infected with avian adeno-viruses. Used for titrations of serum antibody was a microneutralization procedure that is inexpensive. It proved also to provide reproducibility since titers from replicate tests differed by less than 3 twofold dilutions. In addition, there was a strong linear relation between titers obtained with the microneutralization procedure and a conventional plaque-assay titration procedure. The microneutralization procedure was less sensitive than the conventional procedure by a factor of about 5.5, but that was considered a disadvantage only with low-titered serums.

  11. Charge state breeders: On-line results

    NASA Astrophysics Data System (ADS)

    Wenander, Fredrik

    2008-10-01

    The transformation of radioactive ions from 1+ to n+ in the low-energy stage of a post-accelerator - also called charge breeding, has become a mature technique. Several machines using the method are in operation or under construction. This paper will present and evaluate on-line and off-line results from two different breeder types, the EBIS and the ECRIS-based systems. Notable on-line results, in terms of versatility, efficiency and beam purity among other things, have been achieved with the trap-EBIS charge breeding system for REX-ISOLDE, a post-accelerator operational since 2001. These will be compared with breeding results of stable and radioactive beams obtained with ECRIS at a number of facilities using or developing ECRIS breeders. Finally an outlook will be given of the predicted evolution of the charge breeders and how they can meet the requirements of future radioactive beam facilities.

  12. Accelerator breeder with uranium, thorium target

    SciTech Connect

    Takahashi, H.; Powell, J.; Kouts, H.

    1983-01-01

    An accelerator breeder, that uses a low-enriched fuel as the target material, can produce substantial amounts of fissile material and electric power. A study of H/sub 2/O- and D/sub 2/O-cooled, UO/sub 2/, U, (depleted U), or thorium indicates that U-metal fuel produces a good fissile production rate and electrical power of about 60% higher than UO/sub 2/ fuel. Thorium fuel has the same order of magnitude as UO/sub 2/ fuel for fissile-fuel production, but the generating electric power is substantially lower than in a UO/sub 2/ reactor. Enriched UO/sub 2/ fuel increases the generating electric power but not the fissile-material production rate. The Na-cooled breeder target has many advantages over the H/sub 2/O-cooled breeder target.

  13. Entropic effects in a nonequilibrium system: Flocks of birds

    NASA Astrophysics Data System (ADS)

    Castellana, Michele; Bialek, William; Cavagna, Andrea; Giardina, Irene

    2016-05-01

    When European starlings come together to form a flock, the distribution of their individual velocities narrows around the mean velocity of the flock. We argue that, in a broad class of models for the joint distribution of positions and velocities, this narrowing generates an entropic effect that opposes the cohesion of the flock. The strength of this effect depends strongly on the nature of the interactions among birds: If birds are coupled to a fixed number of neighbors, the entropic forces are weak, while if they couple to all other birds within a fixed distance, the entropic effects are sufficient to tear a flock apart.

  14. Entropic effects in a nonequilibrium system: Flocks of birds.

    PubMed

    Castellana, Michele; Bialek, William; Cavagna, Andrea; Giardina, Irene

    2016-05-01

    When European starlings come together to form a flock, the distribution of their individual velocities narrows around the mean velocity of the flock. We argue that, in a broad class of models for the joint distribution of positions and velocities, this narrowing generates an entropic effect that opposes the cohesion of the flock. The strength of this effect depends strongly on the nature of the interactions among birds: If birds are coupled to a fixed number of neighbors, the entropic forces are weak, while if they couple to all other birds within a fixed distance, the entropic effects are sufficient to tear a flock apart. PMID:27300933

  15. Broiler diet modification and litter storage: impacts on phosphorus in litters, soils, and runoff.

    PubMed

    McGrath, Joshua M; Sims, J Thomas; Maguire, Rory O; Saylor, William W; Angel, C Roselina; Turner, Benjamin L

    2005-01-01

    Modifying broiler diets to mitigate water quality concerns linked to excess phosphorus (P) in regions of intensive broiler production has recently increased. Our goals were to evaluate the effects of dietary modification, using phytase and reduced non-phytate phosphorus (NPP) supplementation, on P speciation in broiler litters, changes in litter P forms during long-term storage, and subsequent impacts of diets on P in runoff from litter-amended soils. Four diets containing two levels of NPP with and without phytase were fed to broilers in a three-flock floor pen study. After removal of the third flock, litters were stored for 440 d at their initial moisture content (MC; 24%) and at a MC of 40%. Litter P fractions and orthophosphate and phytate P concentrations were determined before and after storage. After storage, litters were incorporated with a sandy and silt loam and simulated rainfall was applied. Phytase and reduced dietary NPP significantly reduced litter total P. Reducing dietary NPP decreased water-extractable inorganic phosphorus (IP) and the addition of dietary phytase reduced NaOH- and HCl-extractable organic P in litter, which correlated well with orthophosphate and phytic acid measured by 31P nuclear magnetic resonance (NMR), respectively. Although dry storage caused little change in P speciation, wet storage increased concentrations of water-soluble IP, which increased reactive P in runoff from litter-amended soils. Therefore, diet modification with phytase and reduced NPP could be effective in reducing P additions on a watershed scale. Moreover, efforts to minimize litter MC during storage may reduce the potential for dissolved P losses in runoff.

  16. Broiler diet modification and litter storage: impacts on phosphorus in litters, soils, and runoff.

    PubMed

    McGrath, Joshua M; Sims, J Thomas; Maguire, Rory O; Saylor, William W; Angel, C Roselina; Turner, Benjamin L

    2005-01-01

    Modifying broiler diets to mitigate water quality concerns linked to excess phosphorus (P) in regions of intensive broiler production has recently increased. Our goals were to evaluate the effects of dietary modification, using phytase and reduced non-phytate phosphorus (NPP) supplementation, on P speciation in broiler litters, changes in litter P forms during long-term storage, and subsequent impacts of diets on P in runoff from litter-amended soils. Four diets containing two levels of NPP with and without phytase were fed to broilers in a three-flock floor pen study. After removal of the third flock, litters were stored for 440 d at their initial moisture content (MC; 24%) and at a MC of 40%. Litter P fractions and orthophosphate and phytate P concentrations were determined before and after storage. After storage, litters were incorporated with a sandy and silt loam and simulated rainfall was applied. Phytase and reduced dietary NPP significantly reduced litter total P. Reducing dietary NPP decreased water-extractable inorganic phosphorus (IP) and the addition of dietary phytase reduced NaOH- and HCl-extractable organic P in litter, which correlated well with orthophosphate and phytic acid measured by 31P nuclear magnetic resonance (NMR), respectively. Although dry storage caused little change in P speciation, wet storage increased concentrations of water-soluble IP, which increased reactive P in runoff from litter-amended soils. Therefore, diet modification with phytase and reduced NPP could be effective in reducing P additions on a watershed scale. Moreover, efforts to minimize litter MC during storage may reduce the potential for dissolved P losses in runoff. PMID:16151241

  17. Oligosaccharides Affect Performance and Gut Development of Broiler Chickens

    PubMed Central

    Ao, Z.; Choct, M.

    2013-01-01

    The effects of oligosaccharide supplementation on the growth performance, flock uniformity and GIT development of broiler chickens were investigated. Four diets, one negative control, one positive control supplemented with zinc-bacitracin, and two test diets supplemented with mannoligosaccharide (MOS) and fructooligosaccharide (FOS), were used for the experiment. Birds given MOS or FOS had improved body weight (BW) and feed efficiency (FCR), compared to those fed the negative control diet during the 35-d trial period. The effect on FCR became less apparent when the birds got older. FOS and MOS supplementation reduced the pancreas weight as a percentage of BW, with an effect similar to that of the antibiotic, at 35 d of age. Birds given MOS tended to have a heavier bursa (p = 0.164) and lower spleen/bursa weight ratio (p = 0.102) at 35 d of age. MOS and Zn-bacitracin showed a clear improvement on flock uniformity, compared to FOS. The mortality rate was not affected by FOS or MOS. PMID:25049713

  18. Influence of in-house composting of reused litter on litter quality, ammonia volatilisation and incidence of broiler foot pad dermatitis.

    PubMed

    Martins, R S; Hötzel, M J; Poletto, R

    2013-01-01

    1. The objectives of this study were to evaluate the residual effects of two windrow composting methods for reused litter on its quality (pH, moisture, ammonia), ammonia (NH3) volatilisation and the prevalence (scores 0-4) of foot pad dermatitis (FPD) and hock burn (HB) on d 1, 7, 14 and 21 of age in broilers. Litter was allowed to compost for 8 d within a 14-d interval between flocks. 2. The composting methods studied were with or without a PVC plastic sheet. The same procedures were applied for three consecutive flocks, with litter initially having been used for 12 flocks. Data were analysed with a mixed model of repeated measures of day, with main effects and interactions of day, composting method, litter age (block) and house nested within method. 3. At d 1, litter NH3 and NH3 volatilisation were higher in the covered litter method. Litter moisture increased to 45.3% as broilers aged. The incidence of FPD also increased with age. No signs of HB were found in any bird throughout the trials. 4. There was no effect of litter composting methods on the prevalence of FPD or body weight at any age. 5. Litter moisture should be controlled to avoid NH3 volatilisation reaching critical levels. Windrow composting of litter with a PVC plastic sheet may not be required when considering the broiler housing environment.

  19. Influence of in-house composting of reused litter on litter quality, ammonia volatilisation and incidence of broiler foot pad dermatitis.

    PubMed

    Martins, R S; Hötzel, M J; Poletto, R

    2013-01-01

    1. The objectives of this study were to evaluate the residual effects of two windrow composting methods for reused litter on its quality (pH, moisture, ammonia), ammonia (NH3) volatilisation and the prevalence (scores 0-4) of foot pad dermatitis (FPD) and hock burn (HB) on d 1, 7, 14 and 21 of age in broilers. Litter was allowed to compost for 8 d within a 14-d interval between flocks. 2. The composting methods studied were with or without a PVC plastic sheet. The same procedures were applied for three consecutive flocks, with litter initially having been used for 12 flocks. Data were analysed with a mixed model of repeated measures of day, with main effects and interactions of day, composting method, litter age (block) and house nested within method. 3. At d 1, litter NH3 and NH3 volatilisation were higher in the covered litter method. Litter moisture increased to 45.3% as broilers aged. The incidence of FPD also increased with age. No signs of HB were found in any bird throughout the trials. 4. There was no effect of litter composting methods on the prevalence of FPD or body weight at any age. 5. Litter moisture should be controlled to avoid NH3 volatilisation reaching critical levels. Windrow composting of litter with a PVC plastic sheet may not be required when considering the broiler housing environment. PMID:24397504

  20. Genotype-by-environment interaction with broiler genotypes differing in growth rate. 3. Growth rate and water consumption of broiler progeny from weight-selected versus nonselected parents under normal and high ambient temperatures.

    PubMed

    Deeb, N; Cahaner, A

    2002-03-01

    One cycle of high-intensity selection on BW was conducted to study correlated effects on performance under high ambient temperature (AT). From a large flock of a commercial sire-line, 3 males and 15 females with the highest BW at 35 d of age were mated and produced a group of 120 BW-selected chicks. Three average-BW males and 15 average-BW females from the same flock were mated to produce a control group of 120 chicks. On Day 17, the two groups were equally divided between two temperature-controlled chambers and housed in individual cages. One chamber was set to a normal AT (NAT; constant 22 C) and the second chamber to high AT (HAT; constant 32 C). Under NAT, the relative advantage of the selected broilers over the controls did not change from 17 to 42 d of age, averaging about 15% for BW gain and 9.7% for feed consumption. These differences were halved under HAT from Days 17 to 28 and were reversed from 28 to 42 d of age, when the selected broilers consumed significantly less feed and gained less BW than the controls. Water-to-feed ratio was measured in each AT treatment. From 28 to 42 d of age, averaged over the two groups, birds under HAT consumed 2.5 g water/g of feed compared to only 1.5 g water/g feed under NAT. The diminished superiority of the selected broilers under HAT led to a substantial genotype-by-environment interaction involving high AT and within-stock genetic differences in growth rate. It appears that broilers selected for rapid growth under optimal conditions do not achieve their genetic potential under high AT. Thus, specific indicators of adaptation to heat, possibly water consumption or body temperature, should be added to commercial selection for rapid growth to improve broiler performance in hot climates.

  1. [Acute toxoplasmosis outbreak in rabbit flocks].

    PubMed

    Bergmann, V; Heidrich, R; Kiupel, H

    1980-02-01

    Acute toxoplasmosis occurred in 2-18 month old domestic rabbits of 15 flocks entailing losses of 3-66%. Pathomorphological examinations of 49 rabbits revealed lesions of a generalized granulomatous-necrotizing toxoplasmosis with spleen, liver, lungs and lymphonodes mainly affected. Similarities existed to pseudotuberculosis. The spleen was massively packed with pseudocysts and cysts of Toxoplasma. Electronmicroscopic examinations of organ specimens fixed in formalin assured the identity of Toxoplasma and serological tests (CFT, SFT, IFAT) as well as the mouse test confirmed it.

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

    PubMed

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

    2013-01-01

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

  3. Progress and problems in vaccination against necrotic enteritis in broiler chickens.

    PubMed

    Mot, Dorien; Timbermont, Leen; Haesebrouck, Freddy; Ducatelle, Richard; Van Immerseel, Filip

    2014-01-01

    Necrotic enteritis in broilers is caused by Clostridium perfringens type A strains that produce the NetB toxin. Necrotic enteritis is one of the gastrointestinal diseases in poultry that has gained worldwide importance during the last decade due to efforts to improve broiler performance. Prevention strategies include avoiding predisposing factors, such as coccidiosis, and in-feed supplementation with a variety of feed additives. However, vaccination with modified toxin or other secreted immunogenic proteins seems a logical preventive tool for protection against a toxin-producing bacterium. Formalin-inactivated crude supernatant has been used initially for vaccination. Several studies have been carried out recently to identify the most important immunogenic and protective proteins that can be used for vaccination. These include the NetB toxin, as well as a number of other proteins. There is evidence that immunization with single proteins is not protective against severe challenge and that combinations of different antigens are needed. Most published studies have used multiple dosage vaccination regimens that are not relevant for practical use in the broiler industry. Single vaccination regimens for 1-day-old chicks appear to be non-protective. This review describes the history of vaccination strategies against necrotic enteritis in broilers and gives an update on future vaccination strategies that are applicable in the field. These may include breeder hen vaccination, in ovo vaccination and live attenuated vectors to be used in feed or in drinking water.

  4. Stability of model flocks in a vortical flow

    NASA Astrophysics Data System (ADS)

    Baggaley, A. W.

    2016-06-01

    We investigate the stability of self-propelled particle flocks in the Taylor-Green vortex, a steady vortical flow. We consider a model in which particles align themselves to a combination of the orientation and the acceleration of particles within a critical radius. We identify two distinct regimes: If alignment with orientation is dominant, the particles tend to be expelled from regions of high vorticity. In contrast, if anticipation is dominant, the particles accumulate in areas of large vorticity. In both regimes, the relative order of the flock is reduced. However, we show that there can be a critical balance of the two effects that stabilizes the flock in the presence of external fluid forcing. This strategy could provide a mechanism for animal flocks to remain globally ordered in the presence of fluid forcing, and it may also have applications in the design of flocking autonomous drones and artificial microswimmers.

  5. Simulated predator attacks on flocks: a comparison of tactics.

    PubMed

    Demšar, Jure; Lebar Bajec, Iztok

    2014-01-01

    It is not exactly known why birds aggregate in coordinated flocks. The most common hypothesis proposes that the reason is protection from predators. Most of the currently developed examples of individual-based predator-prey models assume predators are attracted to the center of a highly coordinated flock. This proposed attraction of a predator to a flock would appear to be contradictory to an alternate hypothesis that flocks evolved as a protection against predation. In an attempt to resolve this apparent conflict, in this article we use a fuzzy individual-based model to study three attack tactics (attack center, attack nearest, attack isolated) and analyze the success of predation on two types of prey (social and individualistic). Our simulations revealed that social flocking (as opposed to individualistic behavior) is the optimal anti-predatory response to predators attacking mainly isolated individuals. PMID:24730766

  6. Stability of model flocks in a vortical flow.

    PubMed

    Baggaley, A W

    2016-06-01

    We investigate the stability of self-propelled particle flocks in the Taylor-Green vortex, a steady vortical flow. We consider a model in which particles align themselves to a combination of the orientation and the acceleration of particles within a critical radius. We identify two distinct regimes: If alignment with orientation is dominant, the particles tend to be expelled from regions of high vorticity. In contrast, if anticipation is dominant, the particles accumulate in areas of large vorticity. In both regimes, the relative order of the flock is reduced. However, we show that there can be a critical balance of the two effects that stabilizes the flock in the presence of external fluid forcing. This strategy could provide a mechanism for animal flocks to remain globally ordered in the presence of fluid forcing, and it may also have applications in the design of flocking autonomous drones and artificial microswimmers. PMID:27415360

  7. Fast Breeder Reactors in Sweden: Vision and Reality.

    PubMed

    Fjaestad, Maja

    2015-01-01

    The fast breeder is a type of nuclear reactor that aroused much attention in the 1950s and '60s. Its ability to produce more nuclear fuel than it consumes offered promises of cheap and reliable energy. Sweden had advanced plans for a nuclear breeder program, but canceled them in the middle of the 1970s with the rise of nuclear skepticism. The article investigates the nuclear breeder as a technological vision. The nuclear breeder reactor is an example of a technological future that did not meet its industrial expectations. But that does not change the fact that the breeder was an influential technology. Decisions about the contemporary reactors were taken with the idea that in a foreseeable future they would be replaced with the efficient breeder. The article argues that general themes in the history of the breeder reactor can deepen our understanding of the mechanisms behind technological change. PMID:26334698

  8. Fast Breeder Reactors in Sweden: Vision and Reality.

    PubMed

    Fjaestad, Maja

    2015-01-01

    The fast breeder is a type of nuclear reactor that aroused much attention in the 1950s and '60s. Its ability to produce more nuclear fuel than it consumes offered promises of cheap and reliable energy. Sweden had advanced plans for a nuclear breeder program, but canceled them in the middle of the 1970s with the rise of nuclear skepticism. The article investigates the nuclear breeder as a technological vision. The nuclear breeder reactor is an example of a technological future that did not meet its industrial expectations. But that does not change the fact that the breeder was an influential technology. Decisions about the contemporary reactors were taken with the idea that in a foreseeable future they would be replaced with the efficient breeder. The article argues that general themes in the history of the breeder reactor can deepen our understanding of the mechanisms behind technological change.

  9. Current experimental activities for solid breeder development

    SciTech Connect

    Johnson, C.E.; Hollenberg, G.W.; Roux, N.; Watanabe, H.

    1988-01-01

    The current data base for ceramic breeder materials does not exhibit any negative features as regards to thermophysical, mechanical, and irradiation behavior. All candidate materials show excellent stability for irradiation testing to 3% burnup. In-situ tritium recovery tests show very low tritium inventories for all candidates. Theoretical models are being developed to accurately predict real time release rates. Fabrication of kilogram quantities of materials has been achieved and technology is available for further scale-up.

  10. Experimental Breeder Reactor I Preservation Plan

    SciTech Connect

    Julie Braun

    2006-10-01

    Experimental Breeder Reactor I (EBR I) is a National Historic Landmark located at the Idaho National Laboratory, a Department of Energy laboratory in southeastern Idaho. The facility is significant for its association and contributions to the development of nuclear reactor testing and development. This Plan includes a structural assessment of the interior and exterior of the EBR I Reactor Building from a preservation, rather than an engineering stand point and recommendations for maintenance to ensure its continued protection.

  11. A flocking based method for brain tractography.

    PubMed

    Aranda, Ramon; Rivera, Mariano; Ramirez-Manzanares, Alonso

    2014-04-01

    We propose a new method to estimate axonal fiber pathways from Multiple Intra-Voxel Diffusion Orientations. Our method uses the multiple local orientation information for leading stochastic walks of particles. These stochastic particles are modeled with mass and thus they are subject to gravitational and inertial forces. As result, we obtain smooth, filtered and compact trajectory bundles. This gravitational interaction can be seen as a flocking behavior among particles that promotes better and robust axon fiber estimations because they use collective information to move. However, the stochastic walks may generate paths with low support (outliers), generally associated to incorrect brain connections. In order to eliminate the outlier pathways, we propose a filtering procedure based on principal component analysis and spectral clustering. The performance of the proposal is evaluated on Multiple Intra-Voxel Diffusion Orientations from two realistic numeric diffusion phantoms and a physical diffusion phantom. Additionally, we qualitatively demonstrate the performance on in vivo human brain data. PMID:24583805

  12. BREEDER: a microcomputer program for financial analysis of a large-scale prototype breeder reactor

    SciTech Connect

    Giese, R.F.

    1984-04-01

    This report describes a microcomputer-based, single-project financial analysis program: BREEDER. BREEDER is a user-friendly model designed to facilitate frequent and rapid analyses of the financial implications associated with alternative design and financing strategies for electric generating plants and large-scale prototype breeder (LSPB) reactors in particular. The model has proved to be a useful tool in establishing cost goals for LSPB reactors. The program is available on floppy disks for use on an IBM personal computer (or IBM look-a-like) running under PC-DOS or a Kaypro II transportable computer running under CP/M (and many other CP/M machines). The report documents version 1.5 of BREEDER and contains a user's guide. The report also includes a general overview of BREEDER, a summary of hardware requirements, a definition of all required program inputs, a description of all algorithms used in performing the construction-period and operation-period analyses, and a summary of all available reports. The appendixes contain a complete source-code listing, a cross-reference table, a sample interactive session, several sample runs, and additional documentation of the net-equity program option.

  13. Do avian cooperative breeders live longer?

    PubMed Central

    Beauchamp, Guy

    2014-01-01

    Cooperative breeding is not common in birds but intriguingly over-represented in several families, suggesting that predisposing factors, similar ecological constraints or a combination of the two facilitate the evolution of this breeding strategy. The life-history hypothesis proposes that cooperative breeding is facilitated by high annual survival, which increases the local population and leads to a shortage of breeding opportunities. Clutch size in cooperative breeders is also expected to be smaller. An earlier comparative analysis in a small sample of birds supported the hypothesis but this conclusion has been controversial. Here, I extend the analysis to a larger, worldwide sample and take into account potential confounding factors that may affect estimates of a slow pace of life and clutch size. In a sample of 81 species pairs consisting of closely related cooperative and non-cooperative breeders, I did not find an association between maximum longevity and cooperative breeding, controlling for diet, body mass and sampling effort. However, in a smaller sample of 37 pairs, adult annual survival was indeed higher in the cooperative breeders, controlling for body mass. There was no association between clutch size and cooperative breeding in a sample of 93 pairs. The results support the facilitating effect of high annual survival on the evolution of cooperative breeding in birds but the effect on clutch size remains elusive. PMID:24898375

  14. Stochastic model of the potential spread of highly pathogenic avian influenza from an infected commercial broiler operation in Georgia.

    PubMed

    Dorea, F C; Vieira, A R; Hofacre, C; Waldrip, D; Cole, D J

    2010-03-01

    The potential spread of highly pathogenic avian influenza among commercial broiler farms in Georgia, U. S. A., was mathematically modeled. The dynamics of the spread within the first infected flock were estimated using an SEIR (susceptible-exposed-infectious-recovered) deterministic model, and predicted that grower detection of flock infection is most likely 5 days after virus introduction. Off-farm spread of virus was estimated stochastically for this period, predicting a mean range of exposed farms from 0-5, depending on the density of farms in the area. Modeled off-farm spread was most frequently associated with feed trucks (highest daily probability and number of farm visits) and with company personnel or hired help (highest level of bird contact).

  15. Maternal antibody transfer to broiler progeny varies among strains and is affected by grain source and cage density.

    PubMed

    Leandro, N M; Ali, R; Koci, M; Moraes, V; Eusebio-Balcazar, P E; Jornigan, J; Malheiros, R D; Wineland, M J; Brake, J; Oviedo-Rondón, E O

    2011-12-01

    Two experiments were conducted to examine the effects of broiler breeder dietary grain source and cage density on maternal antibody (MatAb) transfer to progeny in 2 genetic strains (A and B). Broiler breeders were assigned to 16 litter floor pens and fed either corn- or wheat-based diets. Breeders were administered 4 live vaccines against Newcastle disease virus (NDV). At 23 wk of age, pullets and cocks, which reflected the full BW distribution from each treatment, were moved to a cage breeder house and placed at 1 or 2 hens/cage. Breeders were artificially inseminated at 44 wk (experiment 1) and 52 wk of age (experiment 2). Eggs were collected for 8 d, incubated, and placed in individual pedigree bags at d 19 of incubation. Blood samples from 5 chicks per treatment combination were collected at hatch in both experiments. Spleen and bursa were collected from the same chicks for histomorphometry analyses in experiment 2. In the second experiment, 12 chicks per treatment were placed in cages. Progeny were provided diets based on the same grain (corn or wheat) as their parents. Serum samples were collected at 5, 9, and 13 d of age and analyzed for anti-NDV MatAb. Data were analyzed as a 2 × 2 × 2 factorial design considering strain, dietary grain source, and cage density as main factors. Interaction effects were observed in breeders and progeny. Experiment 1 showed that strain A chicks had lower levels of MatAb when hens were housed at 2 hens/cage rather than 1 hen/cage. The MatAb levels of strain B chickens were not affected by cage density in either experiment. Experiment 2 demonstrated similar effects of cage density on MatAb levels and the area of bursa follicles for both strains. Progeny of breeders fed corn-based diets had smaller spleen white pulp only when hens were housed at 2 hens/cage compared with 1 hen/cage. The results of these experiments suggest that breeder strain and cage-density conditions affected MatAb transfer to progeny and embryo development

  16. Prevalence of newcastle disease virus in broiler chickens (Gallus gallus) in Brazil

    PubMed Central

    Orsi, M.A.; Doretto Jr, L.; Camillo, S.C.A.; Reischak, D.; Ribeiro, S.A.M.; Ramazzoti, A.; Mendonça, A.O.; Spilki, F.R.; Buzinaro, M.G.; Ferreira, H.L.; Arns, C.W.

    2010-01-01

    This study was carried out during 2002/2003, aiming to determine the prevalence of virulent Newcastle disease virus strains (NDV) in Brazilian commercial poultry farms. Clinical samples were obtained from the Southeastern, Southern and Central-Western regions, which comprise the main area of the Brazilian poultry production. Serum samples and tracheal and cloacal swabs of 23,745 broiler chickens from 1,583 flocks, including both vaccinated chickens and those with no vaccination information, were tested for NDV using a diagnostic ELISA kit. The seropositivity was 39.1%, and the isolation percentage by flock varied from 1.0 to 7.6%, and by region from 6.5 to 58.4%. Higher isolation rates (74.3-83.3%) were obtained after three passages in embryonated chicken eggs. All isolates preliminarily identified as NDV were characterized as nonpathogenic strains, as their Intracerebral Pathogenicity Index (ICPI) was below 0.7. Based on results of this study, Brazil can claim a virulent NDV-free status for commercial flocks. PMID:24031503

  17. Campylobacter infection of broiler chickens in a free-range environment.

    PubMed

    Colles, Frances M; Jones, Tracey A; McCarthy, Noel D; Sheppard, Samuel K; Cody, Alison J; Dingle, Kate E; Dawkins, Marian S; Maiden, Martin C J

    2008-08-01

    Campylobacter jejuni is the most common cause of bacterial gastroenteritis worldwide, with contaminated chicken meat considered to represent a major source of human infection. Biosecurity measures can reduce C. jejuni shedding rates of housed chickens, but the increasing popularity of free-range and organic meat raises the question of whether the welfare benefits of extensive production are compatible with food safety. The widespread assumption that the free-range environment contaminates extensively reared chickens has not been rigorously tested. A year-long survey of 64 free-range broiler flocks reared on two sites in Oxfordshire, UK, combining high-resolution genotyping with behavioural and environmental observations revealed: (i) no evidence of colonization of succeeding flocks by the C. jejuni genotypes shed by preceding flocks, (ii) a high degree of similarity between C. jejuni genotypes from both farm sites, (iii) no association of ranging behaviour with likelihood of Campylobacter shedding, and (iv) higher genetic differentiation between C. jejuni populations from chickens and wild birds on the same farm than between the chicken samples, human disease isolates from the same region and national samples of C. jejuni from chicken meat.

  18. Evaluation of antimicrobial resistance profiles of Salmonella isolates from broiler chickens at slaughter in Alberta, Canada.

    PubMed

    Mainali, C; McFall, M; King, R; Irwin, R

    2014-03-01

    Antimicrobial-resistant Salmonella species are threatening to become a serious public health problem. Therefore, surveillance and prudent use of antimicrobials is needed in both the agricultural and human health sectors. The aim of this study was to describe the antimicrobial susceptibility profiles of Salmonella isolates recovered from healthy broiler chickens at slaughter from November 2004 to April 2005. Salmonella isolates recovered from 36 broiler flocks in Alberta, Canada, were serotyped and tested for antimicrobial susceptibility against 15 antimicrobials. Of 272 Salmonella isolates tested, 64.0% were resistant to one or more antimicrobials, 10.0% were resistant to three or more antimicrobials, and 1.8% were resistant to five antimicrobials. All isolates were susceptible to amikacin, amoxicillin-clavulanic acid, ceftiofur, cefoxitin, ceftriaxone, ciprofloxacin, and nalidixic acid. The highest prevalence of resistance was to tetracycline (54.8%), followed by streptomycin (24.2%) and sulfisoxazole (8.4%). The most common multiantimicrobial resistance patterns were to streptomycin-tetracycline (24.3%), streptomycin-sulfisoxazole-tetracycline (6.6%), and ampicillin-streptomycin-sulfisoxazole-tetracycline (3.7%). The strongest associations were observed between resistance to kanamycin and tetracycline (odds ratio = 65.7, P = 0.001) and to ampicillin and sulfisoxazole (odds ratio = 62.9, P = 0.001). Salmonella Hadar and Salmonella Heidelberg were the two most common serovars accounting for 40.4 and 13.6% of the total isolates, respectively. Eighty-one percent and 12.7% of Salmonella Hadar isolates and 62.0 and 8.1% of Salmonella Heidelberg isolates were resistant to 1 or more and three or more antimicrobials, respectively. The flock level prevalence of resistance ranged from 5.6% for trimethoprim-sulfamethoxazole to 83.3% for tetracycline. This study provides baseline information on antimicrobial susceptibility of Salmonella isolates of broiler chickens at

  19. Multi Robot Flocking Using Cooperative Control for Space Exploration

    NASA Astrophysics Data System (ADS)

    Chandran, Priya

    2012-07-01

    This paper aims at achieving flocking behavior of multi robot systems for space explorations. Cooperative control of unmanned vehicles is used in the survey of unknown environments. Distributed control of multiple vehicles achieves the objective of exploration of wide areas while avoiding obstacles on their path. Gradient based algorithm is used to obtain necessary attractive/repulsive force to maintain flock. Similar force is used to avoid obstacles, which may be present in the environment. Velocity consensus algorithm helps in maintaining the necessary geometry of the flock. A target agent specifies the group behavior for the flock. Two wheel differential robot model with second order dynamics is considered here. Robot motion is assumed to be on plane terrain.

  20. Prevalence and Distribution of Campylobacter jejuni in Small-Scale Broiler Operations.

    PubMed

    Tangkham, Wannee; Janes, Marlene; LeMieux, Frederick

    2016-01-01

    Campylobacter jejuni has been recognized as one of the most prevalent causes of foodborne bacterial illnesses in humans. Previous studies have focused on the transmission routes of C. jejuni from commercial flock farms to the final retail product. The objective of this study was to determine the prevalence of C. jejuni and Campylobacter spp. in eggshells, live birds, feed, drinking water, and the rearing environment in a small-scale broiler operation. Broilers were raised under two different production systems: (i) environmentally controlled housing and (ii) open-air housing with two replications. Each week, samples were collected from eggshells, bird feces, feed, drinking water, enclosures (vertical walls of bird housing), and feed troughs for enumeration and isolation testing. All samples were plated on modified charcoal-cefoperazone-deoxycholate agar to determine the log CFU per gram and percent prevalence of Campylobacter spp. Isolation of C. jejuni was verified with latex agglutination and hippurate hydrolysis tests. The results from this study suggest that vertical transmission of these bacteria from egg surfaces to newly hatched chicks is not a significant risk factor. The results also suggest that the prevalence of C. jejuni at time of harvest (week 6) was significantly higher (P < 0.05) in the open-air housing broilers than in those in the environmentally controlled housing. Elevated levels of cross-contaminants, especially water and feed, may have played a role in this outcome.

  1. Investigation of a chronic feed-passage problem on a broiler farm in northwest Arkansas.

    PubMed

    Apple, R O; Skeeles, J K; Houghten, G E; Beasley, J N; Kim, K S

    1991-01-01

    A commercial broiler farm with a history of poor feed conversion and chronic feed-passage problems was chosen for investigation. Chickens were taken from the broiler flock at specified intervals during growout and tested by virus isolation and enzyme-linked immunosorbent assay (ELISA) for avian reovirus. Abnormal tissue pathology was first seen in the broilers at 9 days of age and continued sporadically throughout the growout period. Antireovirus antibody levels began to increase at 24 days of age. Avian reovirus and avian adenovirus was recovered at different intervals starting at 17 and 31 days of age, respectively. One-day-old specific-pathogen-free chicks housed in filtered-air positive-pressure isolation units were inoculated with two inocula recovered from the field study. Avian reovirus was recovered from the tissues of both treatment groups using chick kidney cells. Significant weight differences were seen in one of the two treatment groups. This avian reovirus was given the name SS-412. PMID:1649595

  2. Investigation of a chronic feed-passage problem on a broiler farm in northwest Arkansas.

    PubMed

    Apple, R O; Skeeles, J K; Houghten, G E; Beasley, J N; Kim, K S

    1991-01-01

    A commercial broiler farm with a history of poor feed conversion and chronic feed-passage problems was chosen for investigation. Chickens were taken from the broiler flock at specified intervals during growout and tested by virus isolation and enzyme-linked immunosorbent assay (ELISA) for avian reovirus. Abnormal tissue pathology was first seen in the broilers at 9 days of age and continued sporadically throughout the growout period. Antireovirus antibody levels began to increase at 24 days of age. Avian reovirus and avian adenovirus was recovered at different intervals starting at 17 and 31 days of age, respectively. One-day-old specific-pathogen-free chicks housed in filtered-air positive-pressure isolation units were inoculated with two inocula recovered from the field study. Avian reovirus was recovered from the tissues of both treatment groups using chick kidney cells. Significant weight differences were seen in one of the two treatment groups. This avian reovirus was given the name SS-412.

  3. Prevalence and Distribution of Campylobacter jejuni in Small-Scale Broiler Operations.

    PubMed

    Tangkham, Wannee; Janes, Marlene; LeMieux, Frederick

    2016-01-01

    Campylobacter jejuni has been recognized as one of the most prevalent causes of foodborne bacterial illnesses in humans. Previous studies have focused on the transmission routes of C. jejuni from commercial flock farms to the final retail product. The objective of this study was to determine the prevalence of C. jejuni and Campylobacter spp. in eggshells, live birds, feed, drinking water, and the rearing environment in a small-scale broiler operation. Broilers were raised under two different production systems: (i) environmentally controlled housing and (ii) open-air housing with two replications. Each week, samples were collected from eggshells, bird feces, feed, drinking water, enclosures (vertical walls of bird housing), and feed troughs for enumeration and isolation testing. All samples were plated on modified charcoal-cefoperazone-deoxycholate agar to determine the log CFU per gram and percent prevalence of Campylobacter spp. Isolation of C. jejuni was verified with latex agglutination and hippurate hydrolysis tests. The results from this study suggest that vertical transmission of these bacteria from egg surfaces to newly hatched chicks is not a significant risk factor. The results also suggest that the prevalence of C. jejuni at time of harvest (week 6) was significantly higher (P < 0.05) in the open-air housing broilers than in those in the environmentally controlled housing. Elevated levels of cross-contaminants, especially water and feed, may have played a role in this outcome. PMID:26735032

  4. Number and distribution of sperm-storage tubules in four strains of broiler breeders

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Restricted to the utero-vaginal junction (UVJ) in the hen's oviduct are tubular invaginations of the surface epithelium collectively referred to as the sperm-storage tubules (SSTs). One would expect that a larger number of SSTs would be positively correlated with longer, sustained fertility. However...

  5. A Novel Mycoplasma sp. Associated with Phallus Disease in Goose Breeders: Pathological and Bacteriological Findings.

    PubMed

    Carnaccini, S; Ferguson-Noel, N M; Chin, R P; Santoro, T; Black, P; Bland, M; Bickford, A A; Sentíes-Cué, C G

    2016-06-01

    In April 2014, poor fertility in a major commercial goose breeder operation in California triggered the submission of six live affected Toulouse ganders ( Anser anser ) to the California Animal Health and Food Safety Laboratory, Turlock branch (University of California-Davis). Toulouse were principally affected among all breeds, and their egg fertility dropped from 65.7% to less than 33.9% in the first 40 days of the 2014 breeding season. The flock consisted of 410 adult birds, 90 males and 320 females, between 2 and 5 yr of age. Inspection of the flock revealed that 44.4% of the Toulouse ganders had severe phallic deformities that prevented them from mating. At postmortem examination, severe yellowish fibrocaseous exudate disrupted the architecture of the phallus and occasionally produced fistulating tracts through the wall of the organ. Microscopically, multifocal lymphoid nodules were noted in the mucosa and submucosa of the phallus and were associated with extensive granulomatous reaction, intralesional bacteria, and spermatozoa. Mycoplasma spp. were isolated from the phallus of affected and nonaffected birds, and PCR protocols targeting the 16S-23S ribosomal RNA intergenic spacer regions and the RNA polymerase beta subunit gene were performed to identify the isolates. Three distinct species were identified on sequencing and analysis using the National Center for Biotechnology Information basic local alignment search tool: Mycoplasma cloacale , Mycoplasma anseris , and an unknown novel Mycoplasma sp. Additionally, Pasteurella multocida , in combination with other bacteria, was also isolated from the phallic lesions and identified as serotype 3 with a DNA profile of 1511 (National Veterinary Service Laboratory). This is the first report of these Mycoplasma spp. and other bacteria associated with reproductive disease in ganders in the United States. PMID:27309284

  6. Assembly of avian mixed-species flocks in Amazonia.

    PubMed

    Graves, G R; Gotelli, N J

    1993-02-15

    Diamond's "assembly rules" model posits that competitive interactions among species govern the composition of avifaunas. Although originally applied to islands in archipelagoes, this controversial set of hypotheses is difficult to test because islands differ in habitat and resource availability, colonization history, and stochastic effects. Permanent mixed-species flocks of Amazonian birds are a model system for testing the assembly rules hypothesis because flocks occur in relatively homogeneous tracts of rain forest and because resident species are potentially interactive from minute to minute. To analyze cooccurrence patterns of species in flocks, we used null models that incorporate realistic autecological colonization parameters. Potentially competing pairs of congeneric species with similar ecologies cooccur in flocks less often than expected by chance, resulting in perfect checkerboard distributions. Interactions among more distantly related species, however, appear to have little effect on the assembly of mixed-species flocks. Checkerboard distributions enhance local species diversity within habitats by generating different combinations of species in different flocks. This process may have contributed to the immense species richness of the Amazonian avifauna. PMID:8433996

  7. FLOCK provides reliable solutions to the "number of populations" problem.

    PubMed

    Duchesne, Pierre; Turgeon, Julie

    2012-01-01

    Identifying groups of individuals forming coherent genetic clusters is relevant to many fields of biology. This paper addresses the K-partition problem: given a collection of genotypes, partition those genotypes into K groups, each group being a sample of the K source populations that are represented in the collection of genotypes. This problem involves allocating genotypes to genetic groups while building those groups at the same time without the use of any other a priori information. FLOCK is a non-Markov chain Monte Carlo (MCMC) algorithm that uses an iterative method to partition a collection of genotypes into k groups. Rules to estimate K are formulated and their validity firmly established by running simulations under several migration rates, migration regimes, number of loci, and values of K. FLOCK tended to build clusters largely consistent with the source samples. The performance of FLOCK was also compared with that of STRUCTURE and BAPS. FLOCK provided more accurate allocations to clusters and more reliable estimates of K; it also ran much faster than STRUCTURE. FLOCK is based on an entirely novel approach and provides a true alternative to the existing, MCMC based, algorithms. FLOCK v.2.0 for microsatellites or for AFLP markers can be downloaded from http://www.bio.ulaval.ca/no_cache/departement/professeurs/fiche_des_professeurs/professeur/11/13/. PMID:22615162

  8. Assembly of avian mixed-species flocks in Amazonia.

    PubMed

    Graves, G R; Gotelli, N J

    1993-02-15

    Diamond's "assembly rules" model posits that competitive interactions among species govern the composition of avifaunas. Although originally applied to islands in archipelagoes, this controversial set of hypotheses is difficult to test because islands differ in habitat and resource availability, colonization history, and stochastic effects. Permanent mixed-species flocks of Amazonian birds are a model system for testing the assembly rules hypothesis because flocks occur in relatively homogeneous tracts of rain forest and because resident species are potentially interactive from minute to minute. To analyze cooccurrence patterns of species in flocks, we used null models that incorporate realistic autecological colonization parameters. Potentially competing pairs of congeneric species with similar ecologies cooccur in flocks less often than expected by chance, resulting in perfect checkerboard distributions. Interactions among more distantly related species, however, appear to have little effect on the assembly of mixed-species flocks. Checkerboard distributions enhance local species diversity within habitats by generating different combinations of species in different flocks. This process may have contributed to the immense species richness of the Amazonian avifauna.

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

    NASA Astrophysics Data System (ADS)

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

    2016-06-01

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

  10. Incidence and mechanism of ciprofloxacin resistance in Campylobacter spp. isolated from commercial poultry flocks in the United Kingdom before, during, and after fluoroquinolone treatment.

    PubMed

    Griggs, Deborah J; Johnson, Maggie M; Frost, Jennifer A; Humphrey, Tom; Jørgensen, Frieda; Piddock, Laura J V

    2005-02-01

    Five commercial broiler flocks were treated with a fluoroquinolone for a clinically relevant infection. Fresh feces from individual chickens and environmental samples were cultured for campylobacters before, during, and weekly posttreatment until slaughter. Both Campylobacter jejuni and C. coli were isolated during all treatment phases. An increased proportion of quinolone-resistant strains was seen during treatment, and these strains persisted posttreatment. One quinolone-resistant isolate of each species, each serotype, and each phage type from each sample at all treatment phases was examined for its phenotype and mechanism of resistance. Two resistant phenotypes were isolated: Nal(r) Cip(r) and Nal(r) Cip(s). The majority (269 of 290) of fluoroquinolone-resistant isolates, whether they were C. jejuni or C. coli, had a mutation in gyrA that resulted in the substitution Thr-86-->Ile. The other gyrA mutations detected were Thr-86-->Ala (n = 17) and Asp-90-->Asn (n = 10). The genotypic variation, based on the silent mutations in gyrA identified by the denaturing high-performance liquid chromatography pattern and DNA sequencing, was used to supplement typing data and provided evidence for both the spread of preexisting resistant strains and the selection of spontaneous resistant mutants in treated flocks. Multidrug resistance was significantly (P < 0.01) associated with resistance to ciprofloxacin. Twenty-five percent (73 of 290) of ciprofloxacin-resistant isolates but only 13% (24 of 179) of susceptible isolates were resistant to three or more unrelated antimicrobial agents. In conclusion, quinolone-resistant campylobacters were isolated from commercial chicken flocks in high numbers following therapy with a veterinary fluoroquinolone. Most ciprofloxacin-resistant isolates had the GyrA substitution Thr-86-->Ile. Resistant isolates were isolated from the feces of some flocks up to the point of slaughter, which may have consequences for public health. PMID:15673754

  11. ITER solid breeder blanket materials database

    SciTech Connect

    Billone, M.C.; Dienst, W.; Flament, T.; Lorenzetto, P.; Noda, K.; Roux, N.

    1993-11-01

    The databases for solid breeder ceramics (Li{sub 2},O, Li{sub 4}SiO{sub 4}, Li{sub 2}ZrO{sub 3} and LiAlO{sub 2}) and beryllium multiplier material are critically reviewed and evaluated. Emphasis is placed on physical, thermal, mechanical, chemical stability/compatibility, tritium, and radiation stability properties which are needed to assess the performance of these materials in a fusion reactor environment. Correlations are selected for design analysis and compared to the database. Areas for future research and development in blanket materials technology are highlighted and prioritized.

  12. Estimating sensitivity and specificity of a PCR for boot socks to detect Campylobacter in broiler primary production using Bayesian latent class analysis.

    PubMed

    Matt, Monika; Nordentoft, Steen; Kopacka, Ian; Pölzler, Thomas; Lassnig, Heimo; Jelovcan, Sandra; Stüger, Hans Peter

    2016-06-01

    The present study compares three different assays for sample collection and detection of Campylobacter spp. in broiler flocks, based on (i) the collection of faecal samples from intestinal organs (caecum), (ii) individual faecal droppings collected from the bedding and (iii) faecal material collected by socks placed on the outside of a pair of boots (boot socks) and used for walking around in the flock. The two first methods are examined for Campylobacter using a culture method (ISO-10272-2:2006), while the boot socks are tested using PCR. The PCR-assay is a genus specific multiplex PCR with primers targeting 16S rDNA in Campylobacter and primers targeting Yersinia ruckerii. Sixty-seven broiler flocks from Austria and 83 broiler flocks from Denmark were included in this prospective study and 89 of these were found to be positive in at least one method (AT: 49 samples, DK: 40 samples) whereas 61 of these were negative in all assays. In Austria samples for the three assays were collected simultaneously, which facilitates a direct comparison of the diagnostic test performance. In Denmark, however, boot socks and faecal droppings were collected three days before slaughter while caecum samples were collected at slaughter. The results were evaluated in the absence of a gold standard using a Bayesian latent class model. Austrian results showed higher sensitivity for PCR detection in sock samples (0.98; Bayesian credible interval (BCI) [0.93-1]) than for culture of faecal droppings (0.86; BCI [0.76-0.91]) or caecal samples (0.92; BCI [0.85-0.97]). The potential impact of Campylobacter introduction within the final three days before slaughter was observed in Denmark, where four flocks were tested negative three days before slaughter, but were detected positive at the slaughterhouse. Therefore the model results for the PCR sensitivity (0.88; BCI [0.83-0.97]) and cultural ISO-method in faecal samples (0.84; BCI [0.76-0.92]) are lower than for caecal samples (0.93; BCI [0

  13. Selection against abdominal fat percentage may increase intramuscular fat content in broilers.

    PubMed

    Leng, L; Zhang, H; Dong, J Q; Wang, Z P; Zhang, X Y; Wang, S Z; Cao, Z P; Li, Y M; Li, H

    2016-10-01

    Excessive abdominal fat content (AFC) has negative impacts on feed efficiency and carcass quality. Unlike AFC, intramuscular fat content (IMFC) could be a favourable trait, which has a positive impact on meat quality. To meet consumers' needs, a long-term goal of broiler breeders is to decrease AFC and improve the IMFC simultaneously. The current study was designed to investigate the relationship between AFC and IMFC and to compare IMFC, including the pectoral major muscle fat content (PIMFC) and intramuscular fat content of leg muscle (LIMFC), between two broiler lines divergently selected for abdominal fat percentage over 17 generations. The results showed that there was a significant difference in PIMFC and LIMFC between the two lines in all five generation populations used. The birds in the lean line had significantly lower AFC but higher PIMFC and LIMFC than the birds in the fat line. We also detected differences in the liver fat content (LFC) between the two lines and the results showed that birds in the fat line had significant higher LFC than birds in the lean line. Our results indicated that a desirable broiler line with higher IMFC but lower AFC could be obtained by genetic selection.

  14. Selection against abdominal fat percentage may increase intramuscular fat content in broilers.

    PubMed

    Leng, L; Zhang, H; Dong, J Q; Wang, Z P; Zhang, X Y; Wang, S Z; Cao, Z P; Li, Y M; Li, H

    2016-10-01

    Excessive abdominal fat content (AFC) has negative impacts on feed efficiency and carcass quality. Unlike AFC, intramuscular fat content (IMFC) could be a favourable trait, which has a positive impact on meat quality. To meet consumers' needs, a long-term goal of broiler breeders is to decrease AFC and improve the IMFC simultaneously. The current study was designed to investigate the relationship between AFC and IMFC and to compare IMFC, including the pectoral major muscle fat content (PIMFC) and intramuscular fat content of leg muscle (LIMFC), between two broiler lines divergently selected for abdominal fat percentage over 17 generations. The results showed that there was a significant difference in PIMFC and LIMFC between the two lines in all five generation populations used. The birds in the lean line had significantly lower AFC but higher PIMFC and LIMFC than the birds in the fat line. We also detected differences in the liver fat content (LFC) between the two lines and the results showed that birds in the fat line had significant higher LFC than birds in the lean line. Our results indicated that a desirable broiler line with higher IMFC but lower AFC could be obtained by genetic selection. PMID:26931078

  15. Repeated isolation of Salmonella enterica Goverdhan, a very rare serovar, from Danish poultry surveillance samples.

    PubMed

    Pedersen, Karl; Sørensen, Gitte; Szabo, Istvan; Hächler, Herbert; Le Hello, Simon

    2014-12-01

    We report here the appearance of a very rare serovar of Salmonella, S. enterica subsp. enterica serovar Goverdhan, in routine Salmonella surveillance samples from Danish poultry production. S. Goverdhan was found on nine occasions: in one broiler breeder farm in October 2010, four broiler farms and one broiler breeder farm in June-September 2012, two broiler breeder flocks simultaneously in June 2013, and one layer flock in July 2013. The five isolates from 2012 and the three isolates from 2013 had identical pulsed-field gel electrophoresis profiles, whereas the profile of the isolate from 2010 deviated in a single band. It is the first time this serovar has been described in samples from poultry. The origin of the bacterium is still unknown, but it is suggested that it may have been a pseudo-outbreak caused by contaminated sampling material. PMID:25448451

  16. Repeated isolation of Salmonella enterica Goverdhan, a very rare serovar, from Danish poultry surveillance samples.

    PubMed

    Pedersen, Karl; Sørensen, Gitte; Szabo, Istvan; Hächler, Herbert; Le Hello, Simon

    2014-12-01

    We report here the appearance of a very rare serovar of Salmonella, S. enterica subsp. enterica serovar Goverdhan, in routine Salmonella surveillance samples from Danish poultry production. S. Goverdhan was found on nine occasions: in one broiler breeder farm in October 2010, four broiler farms and one broiler breeder farm in June-September 2012, two broiler breeder flocks simultaneously in June 2013, and one layer flock in July 2013. The five isolates from 2012 and the three isolates from 2013 had identical pulsed-field gel electrophoresis profiles, whereas the profile of the isolate from 2010 deviated in a single band. It is the first time this serovar has been described in samples from poultry. The origin of the bacterium is still unknown, but it is suggested that it may have been a pseudo-outbreak caused by contaminated sampling material.

  17. A continuum model for flocking: Obstacle avoidance, equilibrium, and stability

    NASA Astrophysics Data System (ADS)

    Mecholsky, Nicholas Alexander

    The modeling and investigation of the dynamics and configurations of animal groups is a subject of growing attention. In this dissertation, we present a partial-differential-equation based continuum model of flocking and use it to investigate several properties of group dynamics and equilibrium. We analyze the reaction of a flock to an obstacle or an attacking predator. We show that the flock response is in the form of density disturbances that resemble Mach cones whose configuration is determined by the anisotropic propagation of waves through the flock. We investigate the effect of a flock 'pressure' and pairwise repulsion on an equilibrium density distribution. We investigate both linear and nonlinear pressures, look at the convergence to a 'cold' (T → 0) equilibrium solution, and find regions of parameter space where different models produce the same equilibrium. Finally, we analyze the stability of an equilibrium density distribution to long-wavelength perturbations. Analytic results for the stability of a constant density solution as well as stability regimes for constant density solutions to the equilibrium equations are presented.

  18. Size differences in migrant sandpiper flocks: ghosts in ephemeral guilds

    USGS Publications Warehouse

    Eldridge, J.L.; Johnson, D.H.

    1988-01-01

    Scolopacid sandpipers were studied from 1980 until 1984 during spring migration in North Dakota. Common species foraging together in mixed-species flocks differed in bill length most often by 20 to 30 percent (ratios from 1.2:1 to 1.3:1). Observed flocks were compared to computer generated flocks drawn from three source pools of Arctic-nesting sandpipers. The source pools included 51 migrant species from a global pool, 33 migrant species from a Western Hemisphere pool, and 13 species that migrated through North Dakota. The observed flocks formed randomly from the available species that used the North Dakota migration corridor but the North Dakota species were not a random selection from the Western Hemisphere and global pools of Arctic-nesting scolopacid sandpipers. In short, the ephemeral, mixed-species foraging flocks that we observed in North Dakota were random mixes from a non-random pool. The size-ratio distributions were consistent with the interpretation that use of this migration corridor by sandpipers has been influenced by some form of size-related selection such as competition.

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

    PubMed

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

    2014-05-01

    Recently, it has become possible to more precisely analyze flocking behavior. Such research has prompted a reconsideration of the notion of neighborhoods in the theoretical model. Flocking based on topological distance is one such result. In a topological flocking model, a bird does not interact with its neighbors on the basis of a fixed-size neighborhood (i.e., on the basis of metric distance), but instead interacts with its nearest seven neighbors. Cavagna et al., moreover, found a new phenomenon in flocks that can be explained by neither metric distance nor topological distance: they found that correlated domains in a flock were larger than the metric and topological distance and that these domains were proportional to the total flock size. However, the role of scale-free correlation is still unclear. In a previous study, we constructed a metric-topological interaction model on three-dimensional spaces and showed that this model exhibited scale-free correlation. In this study, we found that scale-free correlation in a two-dimensional flock was more robust than in a three-dimensional flock for the threshold parameter. Furthermore, we also found a qualitative difference in behavior from using the fluctuation coherence, which we observed on three-dimensional flocking behavior. Our study suggests that two-dimensional flocks try to maintain a balance between the flock size and flock mobility by breaking into several smaller flocks. PMID:24686118

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

    PubMed

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

    2014-05-01

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

  1. Development of advanced tritium breeders and neutron multipliers for DEMO solid breeder blankets

    NASA Astrophysics Data System (ADS)

    Tsuchiya, K.; Hoshino, T.; Kawamura, H.; Mishima, Y.; Yoshida, N.; Terai, T.; Tanaka, S.; Munakata, K.; Kato, S.; Uchida, M.; Nakamichi, M.; Yamada, H.; Yamaki, D.; Hayashi, K.

    2007-09-01

    In efforts to develop advanced tritium breeders, the effects of additives to lithium titanate (Li2TiO3) have been investigated, and good prospects have been obtained by using oxide additives such as TiO2, CaO and Li2O. As for the neutron multiplier, the development of a real-size electrode fabrication technique and the characterization of beryllium-based intermetallic compounds such as Be-Ti and Be-V have been performed. Properties of Be-Ti alloys have been found to be better than those of beryllium metal. In particular, steam interaction of a Be-Ti alloy was about 1/1000 as small as that of beryllium metal. These activities have led to bright prospects for the realization of the water-cooled DEMO breeder blanket by application of these advanced materials.

  2. A Coronavirus Associated with Runting Stunting Syndrome in Broiler Chickens.

    PubMed

    Hauck, Rüdiger; Gallardo, Rodrigo A; Woolcock, Peter R; Shivaprasad, H L

    2016-06-01

    Runting stunting syndrome (RSS) is a disease condition that affects broilers and causes impaired growth and poor feed conversion because of enteritis characterized by pale and distended small intestines with watery contents. The etiology of the disease is multifactorial, and a large variety of viral agents have been implicated. Here we describe the detection and isolation of an infectious bronchitis virus (IBV) -like coronavirus from the intestines of a flock of 60,000 14-day-old brown/red broiler chicks. The birds showed typical clinical signs of RSS including stunting and uneven growth. At necropsy, the small intestines were pale and distended with watery contents. Histopathology of the intestines revealed increased cellularity of the lamina propria, blunting of villi, and cystic changes in the crypts. Negative stain electron microscopy of the intestinal contents revealed coronavirus particles. Transmission electron microscopy of the intestine confirmed coronavirus in the cytoplasm of enterocytes. Using immunohistochemistry (IHC), IBV antigen was detected in the intestinal epithelial cells as well as in the proventriculus and pancreas. There were no lesions in the respiratory system, and no IBV antigen was detected in trachea, lung, air sac, conjunctiva, and cecal tonsils. A coronavirus was isolated from the intestine of chicken embryos but not from the allantoic sac inoculated with the intestinal contents of the broiler chicks. Sequencing of the S1 gene showed nucleic acid sequence identities of 93.8% to the corresponding region of IBV California 99 and of 85.7% to IBV Arkansas. Nucleic acid sequence identities to other IBV genotypes were lower. The histopathologic lesions in the intestines were reproduced after experimental infection of specific-pathogen-free chickens inoculated in the conjunctiva and nares. Five days after infection, six of nine investigated birds showed enteritis associated with IBV antigen as detected by IHC. In contrast to the field

  3. Effect of transportation duration of 1-day-old chicks on postplacement production performances and pododermatitis of broilers up to slaughter age.

    PubMed

    Bergoug, H; Guinebretière, M; Tong, Q; Roulston, N; Romanini, C E B; Exadaktylos, V; Berckmans, D; Garain, P; Demmers, T G M; McGonnell, I M; Bahr, C; Burel, C; Eterradossi, N; Michel, V

    2013-12-01

    This experiment studied the effect of transportation duration of 1-d-old chicks on dehydration, mortality, production performance, and pododermatitis during the growout period. Eggs from the same breeder flock (Ross PM3) were collected at 35, 45, and 56 wk of age, for 3 successive identical experiments. In each experiment, newly hatched chicks received 1 of 3 transportation duration treatments from the hatchery before placement in the on-site rearing facility: no transportation corresponding to direct placement in less than 5 min (T00), or 4 (T04) or 10 h (T10) of transportation. The chicks were housed in 35-m(2) pens (650 birds each) and reared until 35 d old. Hematocrit and chick BW were measured on sample chicks before and after transportation. During the growout period, bird weight, feed uptake, and feed conversion ratio were measured weekly until slaughter. Transportation duration affected BW; T00 groups had a significantly higher BW than T04 and T10 transported birds but this effect lasted only until d 21. No clear effect on hematocrit, feed uptake, feed conversion ratio, or mortality was observed for birds transported up to 10 h. The decrease in weight in T10 birds was associated with less severe pododermatitis. Increasing age of the breeder flock was correlated with reduced egg fertility and hatchability, and also with higher quality and BW of hatched chicks. Chicks from older breeders also exhibited reduced mortality during the growout period.

  4. Flocking States of Self-Propelling Particles in Free Space

    NASA Astrophysics Data System (ADS)

    Leung, Kwan-Tai; Chen, Hsuan-Yi

    We present particle-based simulations for the flocking behavior of self-propelling particles. Built upon previous models, our models include realistic but simple rules for the self-propelling, drag, and inter-particle interactions. Depending on both the strength and range of the interactions, a host of stationary phases appear, including independent wandering, formation flight, swarm, and rotating vortex. Of particular interest, we determine that the rotating flock can only arise in the absence of long-range alignment. We also construct a phenomenological continuum model and obtain steady-state solutions for the rotating state.

  5. Effect of inertia on model flocks in a turbulent environment

    NASA Astrophysics Data System (ADS)

    Choudhary, Ashok; Venkataraman, Divya; Sankar Ray, Samriddhi

    2015-10-01

    We study flocking of self-propelled, interacting microorganisms with finite sizes and mass immersed in a turbulent flow. In the presence of the competing interactions of self-propulsion and the carrier turbulent flow, as is typical in nature, we show that including the effect of inertia is essential for the stability of flocks. We examine the problem from the point of view of global as well as local order and the statistics of the velocity of the microorganisms as a function of the inertia, the interaction radius, the level of self-propulsion as well as noise.

  6. Belgian citizens' and broiler producers' perceptions of broiler chicken welfare in Belgium versus Brazil.

    PubMed

    Vanhonacker, F; Tuyttens, F A M; Verbeke, Wim

    2016-07-01

    New EU regulations require more stringent country-of-origin labeling, while imports of broiler meat from non-EU countries are increasing. In light of these trends, we have studied citizens' and producers' perceptions of broiler meat originating from Belgium versus Brazil and their perception of broiler production in Belgium versus Brazil. A particular focus was the association between country of origin and perceived level of animal welfare. We also investigated the perception of scaling-up and outdoor access in terms of perceived level of animal welfare. Cross-sectional survey data was collected among Flemish citizens (n = 541) and broiler producers (n = 114). In accordance with literature on general farm animal welfare, both stakeholder types claimed to allocate great importance to broiler welfare and generally agreed with the Welfare Quality model of broiler welfare. Citizens disagreed with the producers that 1) consumers are not willing to pay more for higher welfare products, 2) that broilers suffer little, 3) that broiler welfare in current Belgian production units is generally non-problematic, 4) that scaling-up production units would not have a positive impact on profitability nor a profoundly negative impact on broiler welfare, and 5) that the impact of providing broilers with outdoor access is negative for consumers, farmers, and broilers. Country of origin had a strong influence on the perception of both broiler production and broiler meat. Belgian citizens, and producers (much more than citizens) considered nearly all aspects related to broiler production and broiler meat to be significantly superior for chicken produced in Belgium compared to Brazil. Further research should focus on how these perceptions influence purchase intentions and production decisions. Future avenues for research are to quantify market opportunities for country-of-origin labeling and to investigate to which extent stakeholders' perceptions correspond with reality.

  7. Beam injection improvement for electron cyclotron resonance charge breeders

    SciTech Connect

    Lamy, T.; Angot, J.; Sortais, P.; Thuillier, T.

    2012-02-15

    The injection of a 1+ beam into an electron cyclotron resonance (ECR) charge breeder is classically performed through a grounded tube placed on its axis at the injection side. This tube presents various disadvantages for the operation of an ECR charge breeder. First experiments without a grounded tube show a better use of the microwave power and a better charge breeding efficiency. The optical acceptance of the charge breeder without decelerating tube allows the injection of high intensity 1+ ion beams at high energy, allowing metals sputtering inside the ion source. The use of this method for refractory metallic ion beams production is evaluated.

  8. 9 CFR 145.93 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... within the State are required to report to the Official State Agency within 48 hours the source of all... equivalent requirements under official supervision; and (iii) The flock is located on a premises where a... flocks or from flocks that met equivalent requirements under official supervision, and is located in...

  9. 9 CFR 145.93 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Meat-Type Waterfowl Breeding Flocks and Products § 145.93 Terminology and... months with no reactors. (2) It is a multiplier breeding flock, or a breeding flock composed of...

  10. 9 CFR 145.93 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Meat-Type Waterfowl Breeding Flocks and Products § 145.93 Terminology and... months with no reactors. (2) It is a multiplier breeding flock, or a breeding flock composed of...

  11. Molecular typing and antimicrobial susceptibility of Clostridium perfringens from broiler chickens.

    PubMed

    Gharaibeh, Saad; Al Rifai, Rami; Al-Majali, Ahmad

    2010-12-01

    Clostridium perfringens (Cp) causes necrotic enteritis disease in commercial poultry. Antimicrobials are used to control and treat this disease and sometimes clinical outbreaks do not respond well to certain treatments. This study was designed to isolate Cp from clinical cases, type these isolates by multiplex PCR, and determine their antimicrobial susceptibility by micro-dilution method. A total of 67 Cp isolates were obtained from 155 broiler chicken flocks. All isolates were classified as type A and non-enterotoxin producers. Lincomycin, erythromycins, and tilmicosin showed very high minimal inhibitory concentration (MIC) 50 of ≥256 μg/ml. However, tylosin, amoxicillin, ampicillin, penicillin, florfenicol, danofloxacin, enrofloxacin, chlortetracycline, doxycycline, and oxytetracycline had variable MIC₅₀ of 64, 0.5, 1, 1, 8, 4, 8, 4, 8, 0.5 μg/ml, respectively. It is recommended that Cp infections in Jordan be treated with either penicillins or tetracyclines especially amoxicillin and oxytetracycline. PMID:20969969

  12. Effect of acquisition of improved thermotolerance on the induction of heat shock proteins in broiler chickens.

    PubMed

    Yahav, S; Shamay, A; Horev, G; Bar-Ilan, D; Genina, O; Friedman-Einat, M

    1997-10-01

    The role of heat shock proteins (HSP) in the protection of cells from heat stress is well established. However, very little is known about their contribution to thermotolerance in the complexity of a whole homeotherm animal. Here we report on the analysis of protein synthesis in lung and heart muscle tissues of broiler chickens following exposure to high ambient temperature. Half of the flock was treated by an early age exposure to heat (conditioning), to improve thermotolerance. In contrast to what has been expected, lower levels of HSP induction was observed in the treated chickens. We suggest that 1) the induction of HSP in the heart and lung tissues of the whole animal correlates with the body temperature and 2) HSP response does not represent a part of the long-term mechanism that is evoked by the early age conditioning. PMID:9316120

  13. Real-time qPCR is a powerful assay to estimate the 171 R/Q alleles at the PrP locus directly in a flock's raw milk: a comparison with the targeted next-generation sequencing.

    PubMed

    Feligini, Maria; Bongioni, Graziella; Brambati, Eva; Amadesi, Alessandra; Cambuli, Caterina; Panelli, Simona; Bonacina, Cesare; Galli, Andrea

    2014-10-01

    The hazard to human health represented by transmissible spongiform encephalopathies in sheep is one of the major reasons for implementing the genetic selection plan to break down prion diseases. The problem is particularly important because of the risk of disease transmission from ewe to lamb via milk or colostrum. In order to establish an active and convenient monitoring of the flocks already undergone genetic selection and thus, indirectly increase consumers' security, the challenge of the work was quantifying the classical scrapie risk in bulk milk. A new quantitative real-time PCR assay for the estimation of the 171 R and Q allelic frequencies in a DNA pool representative of all the lactating ewes present in a flock was optimized and validated "in field". The repeatability range was 3.69-5.27 for R and 4.20-5.75 for Q. The ruggedness of the allele frequencies resulted 4.26 for R and 4.77 for Q. Regarding the validation "in field", none of the considered sources of variability (flock, month, number of genotyped animals and somatic cell count) showed a significant effect on flock and milk at the linear model. The targeted next-generation sequencing was also tested to evaluate its applicability in this context. Results show that the real-time PCR assay could represent a valid tool for the determination of 171 R/Q allele frequencies in bulk milk. The implementation of a service for breeder self-control along the production chain would aim to increase the production of high-security dairy products, while monitoring over time of the effects of genetic selection in the flocks.

  14. Poultry litter and the environment: Physiochemical properties of litter and soil during successive flock rotations and after remote site deposition.

    PubMed

    Crippen, Tawni L; Sheffield, Cynthia L; Byrd, J Allen; Esquivel, Jesus F; Beier, Ross C; Yeater, Kathleen

    2016-05-15

    The U.S. broiler meat market has grown over the past 16 years and destinations for U.S. broiler meat exports expanded to over 150 countries. This market opportunity has spurred a corresponding increase in industrialized poultry production, which due to the confined space in which high numbers of animals are housed, risks accumulating nutrients and pollutants. The purpose of this research was to determine the level of pollutants within poultry litter and the underlying soil within a production facility; and to explore the impact of spent litter deposition into the environment. The study follows a production facility for the first 2.5 years of production. It monitors the effects of successive flocks and management practices on 15 physiochemical parameters: Ca, Cu, electrical conductivity, Fe, K, Mg, Mn, moisture, Na, NO3(-)/N, organic matter, P, pH, S, and Zn. Litter samples were collected in-house, after clean-outs and during stockpiling. The soil before house placement, after the clean-outs and following litter stockpiling was monitored. Management practices markedly altered the physiochemical profiles of the litter in-house. A canonical discriminant analysis was used to describe the relationship between the parameters and sampling times. The litter profiles grouped into five clusters corresponding to time and management practices. The soil in-house exhibited mean increases in all physiochemical parameters (2-297 fold) except Fe, Mg, %M, and pH. The spent litter was followed after deposition onto a field for use as fertilizer. After 20 weeks, the soil beneath the litter exhibited increases in EC, Cu, K, Na, NO3(-)/N, %OM, P, S and Zn; while %M decreased. Understanding the impacts of industrialized poultry farms on the environment is vital as the cumulative ecological impact of this land usage could be substantial if not properly managed to reduce the risk of potential pollutant infiltration into the environment. PMID:26990075

  15. Poultry litter and the environment: Physiochemical properties of litter and soil during successive flock rotations and after remote site deposition.

    PubMed

    Crippen, Tawni L; Sheffield, Cynthia L; Byrd, J Allen; Esquivel, Jesus F; Beier, Ross C; Yeater, Kathleen

    2016-05-15

    The U.S. broiler meat market has grown over the past 16 years and destinations for U.S. broiler meat exports expanded to over 150 countries. This market opportunity has spurred a corresponding increase in industrialized poultry production, which due to the confined space in which high numbers of animals are housed, risks accumulating nutrients and pollutants. The purpose of this research was to determine the level of pollutants within poultry litter and the underlying soil within a production facility; and to explore the impact of spent litter deposition into the environment. The study follows a production facility for the first 2.5 years of production. It monitors the effects of successive flocks and management practices on 15 physiochemical parameters: Ca, Cu, electrical conductivity, Fe, K, Mg, Mn, moisture, Na, NO3(-)/N, organic matter, P, pH, S, and Zn. Litter samples were collected in-house, after clean-outs and during stockpiling. The soil before house placement, after the clean-outs and following litter stockpiling was monitored. Management practices markedly altered the physiochemical profiles of the litter in-house. A canonical discriminant analysis was used to describe the relationship between the parameters and sampling times. The litter profiles grouped into five clusters corresponding to time and management practices. The soil in-house exhibited mean increases in all physiochemical parameters (2-297 fold) except Fe, Mg, %M, and pH. The spent litter was followed after deposition onto a field for use as fertilizer. After 20 weeks, the soil beneath the litter exhibited increases in EC, Cu, K, Na, NO3(-)/N, %OM, P, S and Zn; while %M decreased. Understanding the impacts of industrialized poultry farms on the environment is vital as the cumulative ecological impact of this land usage could be substantial if not properly managed to reduce the risk of potential pollutant infiltration into the environment.

  16. Light-water breeder reactors: preliminary safety and environmental information document. Volume III

    SciTech Connect

    Not Available

    1980-01-01

    Information is presented concerning prebreeder and breeder reactors based on light-water-breeder (LWBR) Type 1 modules; light-water backfit prebreeder supplying advanced breeder; light-water backfit prebreeder/seed-blanket breeder system; and light-water backfit low-gain converter using medium-enrichment uranium, supplying a light-water backfit high-gain converter.

  17. Knowledge and attitudes toward food safety and use of good production practices among Canadian broiler chicken producers.

    PubMed

    Young, Ian; Rajić, Andrijana; Letellier, Ann; Cox, Bill; Leslie, Mira; Sanei, Babak; McEwen, Scott A

    2010-07-01

    Provincial broiler-chicken marketing boards in Canada have recently implemented an on-farm food safety program called Safe, Safer, Safest. The purpose of this study was to measure broiler chicken producers' attitudes toward the program and food safety topics and use of highly recommended good production practices (GPP). Mailed and Web-based questionnaires were administered to all producers registered in British Columbia, Ontario, and Quebec in 2008. The response percentage was 33.2% (642 of 1,932). Nearly 70% of respondents rated the program as effective in producing safe chicken, and 49.1% rated the program requirements as easy to implement. Most respondents (92.9%) reported that they do not raise other poultry or keep birds as pets, and 79.8% reported that they clean and disinfect their barns between each flock cycle. Less than 50% of respondents reported that visitors wash their hands or change their clothes before entering barns, 38.4% reported that catching crews wear clean clothes and boots, and 35.8% reported that a crew other than from the hatchery places chicks. Respondents who rated the program requirements as effective or easy to implement were more likely to report the use of five of six highly recommended GPP. Only 21.1% of respondents indicated that Campylobacter can be transmitted from contaminated chicken meat to humans, and 26.6% believed that antimicrobial use in their industry is linked to antimicrobial resistance in humans. Continuing education of producers should focus on improving their awareness of these issues, while mandatory GPP should include those that are known to be effective in controlling Campylobacter and Salmonella in broiler chicken flocks.

  18. Evaluation of antimicrobial resistance profiles of escherichia coli isolates of broiler chickens at slaughter in Alberta, Canada.

    PubMed

    Mainali, Chunu; McFall, Margaret; King, Robin; Irwin, Rebecca

    2013-12-01

    This study was conducted to investigate antimicrobial resistance profiles of Escherichia coli isolates from broiler chickens in Alberta, Canada. Cecal contents of broiler chickens from 24 flocks were collected at slaughter between January and March 2005 for culture and antimicrobial susceptibility testing against a panel of 15 antimicrobials using a broth microdilution technique. Of 600 E. coli isolates tested, 475 (79.2%) were resistant to one or more antimicrobials, 326 (54.3%) were resistant to three or more antimicrobials, 65 (10.8%) were resistant to five or more antimicrobials, and 15 (2.5%) were resistant to seven or more antimicrobials. The most common resistance was to tetracycline (69.2%), followed by streptomycin (48.2%), kanamycin (40.3%), and sulfisoxazole (38.0%). None of the E. coli isolates were resistant to amikacin, ceftriaxone, or ciprofloxacin. Of the isolates that were resistant to two or more antimicrobials, the most common multidrug resistance patterns were streptomycinte-tracycline (44.0%), streptomycin-sulfisoxazole-tetracycline (30.7%), and kanamycin-streptomycin-sulfisoxazole-tetracycline (23.5%). Resistance to tetracycline and kanamycin (odds ratio = 46.7, P = 0.0001) was highly associated, followed by resistance to streptomycin and sulfisoxazole (odds ratio = 12.0, P = 0.0001), and streptomycin and tetracycline (odds ratio = 10.3, P = 0.0001). The flock level prevalence of resistance varied from 16.7% for chloramphenicol to 100.0% for ampicillin, streptomycin, sulfisoxazole, and tetracycline. The results of this study provided baseline information on antimicrobial susceptibility of E. coli isolates of broiler chickens at slaughter in Alberta, which can serve as a bench mark for future research.

  19. Risk based microbiological criteria for Campylobacter in broiler meat in the European Union.

    PubMed

    Nauta, Maarten J; Sanaa, Moez; Havelaar, Arie H

    2012-09-01

    Quantitative microbiological risk assessment (QMRA) allows evaluating the public health impact of food safety targets to support the control of foodborne pathogens. We estimate the risk reduction of setting microbiological criteria (MCs) for Campylobacter on broiler meat in 25 European countries, applying quantitative data from the 2008 EU baseline survey. We demonstrate that risk based MCs can be derived without explicit consideration of Food Safety Objectives or Performance Objectives. Published QMRA models for the consumer phase and dose response provide a relation between Campylobacter concentration on skin samples and the attending probability of illness for the consumer. Probabilistic modelling is used to evaluate a set of potential MCs. We present the percentage of batches not complying with the potential criteria, in relation to the risk reduction attending totally efficient treatment of these batches. We find different risk estimates and different impacts of MCs in different countries, which offers a practical and flexible tool for risk managers to select the most appropriate MC by weighing the costs (i.e. non-compliant batches) and the benefits (i.e. reduction in public health risk). Our analyses show that the estimated percentage of batches not complying with the MC is better correlated with the risk estimate than surrogate risk measures like the flock prevalence or the arithmetic mean concentration of bacteria on carcasses, and would therefore be a good measure for the risk of Campylobacter on broiler meat in a particular country. Two uncertain parameters in the model are the ratio of within- and between-flock variances in concentrations, and the transition factor of skin sample concentrations to concentrations on the meat. Sensitivity analyses show that these parameters have a considerable effect on our results, but the impact of their uncertainty is small compared to that of the parameters defining the Microbiological Criterion and the concentration

  20. Prevalence of and risk factors for Campylobacter spp. contamination of broiler chicken carcasses at the slaughterhouse.

    PubMed

    Hue, Olivier; Le Bouquin, Sophie; Laisney, Marie-José; Allain, Virginie; Lalande, Françoise; Petetin, Isabelle; Rouxel, Sandra; Quesne, Ségolène; Gloaguen, Pierre-Yves; Picherot, Mélanie; Santolini, Julien; Salvat, Gilles; Bougeard, Stéphanie; Chemaly, Marianne

    2010-12-01

    A study was conducted in 2008 to estimate the prevalence and identify the risk factors for Campylobacter spp. contamination of broiler carcasses during the slaughtering process. A pool of 10 caeca and one carcass were collected from 425 batches of broiler chickens slaughtered in 58 French slaughterhouses over a 12-month period. Potential risk factors were identified according to the Campylobacter contamination status of carcasses and processing variables identified from questionnaires. The statistical analysis took into account confounding factors that have already been associated with the presence of Campylobacter on carcasses such as the slaughter age of the chicken or seasonal variations. Campylobacter spp. were isolated from 77.2% of caeca (95% CI 73.2 to 81.2) and from 87.5% of carcasses (95% CI 84.4 to 90.7). A multiple logistic regression showed 4 parameters as significant risk factors (p < 0.05) for contamination: (I) batches were not the first to be slaughtered in the logistic schedule (OR = 3.5), (II) temperature in the evisceration room was higher than 15 °C (OR = 3.1), (III) dirty marks on carcasses after evisceration were visible (OR = 2.6) and (IV) previous thinning of the flocks, from which slaughtered batches came, had occurred at the farm (OR = 3.3). This last result highlighted the need for sanitary precautions to be taken when catching birds for transport. At the slaughterhouse, evisceration seemed to be the operation contributing most to the spread of contamination. Effective risk management solutions could include the systematic external rinsing of carcasses after evisceration and the implementation of slaughtering schedules according to the Campylobacter contamination status of flocks.

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

    PubMed

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

    2007-08-01

    We examined the importance of mixed-species flock abundance, individual bird home range size, foraging height, and foraging patch characteristics in predicting the propensity for five Neotropical passerine bird species (Slaty Antwren, Myrmotherula schisticolor; Golden-crowned Warbler, Basileuterus culicivorus; Slate-throated Redstart, Myioborus miniatus; Wilson's Warbler, Wilsonia pusilla; and Black-and-white Warbler, Mniotilta varia) to forage within flocks, rather than solitarily. We used study plots in primary mid-elevation forest and in shade coffee fields in western Panama. We expected that all species would spend as much time as possible flocking, but that the social and environmental factors listed above would limit compatibility between flock movements and individual bird movements, explaining variability in flocking propensity both within and among species. Flocking propensity was well predicted by home range size and flock abundance together, for four of the five species. While flock abundance was uniform across plots, home range sizes varied among species and plots, so that home range size appeared to be the principle factor limiting flocking propensity. Estimates of flock abundance were still required, however, for calculating flocking propensity values. Foraging height and patch characteristics slightly improved predictive ability for the remaining species, M. miniatus. In general, individual birds tended to join flocks whenever one was available inside their home range, regardless of a flock's specific location within the home range. Flocking propensities of individual species were lower in shade coffee fields than in forests, and probably vary across landscapes with variations in habitat. This variability affects the stability and species composition of flocks, and may affect survival rates of individual species. PMID:17375332

  2. 78 FR 25943 - Changes to Scrapie Flock Certification Program

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-03

    ... and goat flock owners who wish to reduce and/or eliminate the risk of introducing classical scrapie... sheep and goats. ] DATES: We will consider all comments that we receive on or before June 3, 2013... disease affecting the central nervous systems of sheep and goats. It belongs to a group of diseases...

  3. Topological-distance-dependent transition in flocks with binary interactions.

    PubMed

    Bhattacherjee, Biplab; Mishra, Shradha; Manna, S S

    2015-12-01

    We have studied a flocking model with binary interactions (binary flock), where the velocity of an agent depends on the velocity of only another agent and its own velocity, topped by the angular noise. The other agent is selected as the nth topological neighbor; the specific value of n being a fixed parameter of the problem. On the basis of extensive numerical simulation results, we argue that for n = 1, the phase transition from the ordered to the disordered phase of the flock is a special kind of discontinuous transition. Here, the order parameter does not flip-flop between multiple metastable states. It continues its initial disordered state for a period t(c), then switches over to the ordered state and remains in this state ever after. For n = 2, it is the usual discontinuous transition between two metastable states. Beyond this range, the continuous transitions are observed for n≥3. Such a system of binary flocks has been further studied using the hydrodynamic equations of motion. Linear stability analysis of the homogeneous polarized state shows that such a state is unstable close to the critical point and above some critical speed, which increases as we increase n. The critical noise strengths, which depend on the average correlation between a pair of topological neighbors, are estimated for five different values of n, which match well with their simulated values. PMID:26764659

  4. Speed Determines Leadership and Leadership Determines Learning during Pigeon Flocking.

    PubMed

    Pettit, Benjamin; Ákos, Zsuzsa; Vicsek, Tamás; Biro, Dora

    2015-12-01

    A key question in collective behavior is how individual differences structure animal groups, affect the flow of information, and give some group members greater weight in decisions. Depending on what factors contribute to leadership, despotic decisions could either improve decision accuracy or interfere with swarm intelligence. The mechanisms behind leadership are therefore important for understanding its functional significance. In this study, we compared pigeons' relative influence over flock direction to their solo flight characteristics. A pigeon's degree of leadership was predicted by its ground speeds from earlier solo flights, but not by the straightness of its previous solo route. By testing the birds individually after a series of flock flights, we found that leaders had learned straighter homing routes than followers, as we would expect if followers attended less to the landscape and more to conspecifics. We repeated the experiment from three homing sites using multiple independent flocks and found individual consistency in leadership and speed. Our results suggest that the leadership hierarchies observed in previous studies could arise from differences in the birds' typical speeds. Rather than reflecting social preferences that optimize group decisions, leadership may be an inevitable consequence of heterogeneous flight characteristics within self-organized flocks. We also found that leaders learn faster and become better navigators, even if leadership is not initially due to navigational ability. The roles that individuals fall into during collective motion might therefore have far-reaching effects on how they learn about the environment and use social information.

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

    NASA Astrophysics Data System (ADS)

    Yllanes, David; Marchetti, M. Cristina

    Minimal models of active particles have had much success in the study of flocking behavior. Typically one considers a system of self-propelled particles with noisy aligning interactions. By varying the density of the system or the intensity of the noise one can switch between a disordered phase where the particles move randomly and independently and a flocking state where the velocities of the particles are aligned. In this work we consider what happens if a fraction p of the particles does not experience the aligning interaction. This is an interesting problem from a statistical mechanics point of view, with applications to collective behavior of living systems, where not all the members of a community (a flock of birds, a herd of sheep, etc.) behave in the same way. By carrying out extensive molecular dynamics simulations we show that even a very small fraction of such ''individualistic'' particles can have a dramatic effect on the whole system and, indeed, that the flocking can be destroyed for a very low value of p. We acknowledge support from NSF-DMR-305184 and the Syracuse Soft Matter Program.

  6. Two-level leader-follower organization in pigeon flocks

    NASA Astrophysics Data System (ADS)

    Chen, Zhiyong; Zhang, Hai-Tao; Chen, Xi; Chen, Duxin; Zhou, Tao

    2015-10-01

    The most attractive trait of collective animal behavior is the emergence of highly ordered structures (Cavagna A., Giardina I. and Ginelli F., Phys. Rev. Lett., 110 (2013) 168107). It has been conjectured that the interaction mechanism in pigeon flock dynamics follows a hierarchical leader-follower influential network (Nagy M., Ákos Z., Biro D. and Vicsek T., Nature, 464 (2010) 890). In this paper, a new observation is reported that shows that pigeon flocks actually adopt a much simpler two-level interactive network composed of one leader and some followers. By statistically analyzing the same experimental dataset, we show that for a certain period of time a sole leader determines the motion of the flock while the remaining birds are all followers directly copying the leader's direction with specific time delays. This simple two-level despotic organization is expected to save both motional energy and communication cost, while retaining agility and robustness of the whole group. From an evolutionary perspective, our results suggest that a two-level organization of group flight may be more efficient than a multilevel topology for small pigeon flocks.

  7. Speed Determines Leadership and Leadership Determines Learning during Pigeon Flocking.

    PubMed

    Pettit, Benjamin; Ákos, Zsuzsa; Vicsek, Tamás; Biro, Dora

    2015-12-01

    A key question in collective behavior is how individual differences structure animal groups, affect the flow of information, and give some group members greater weight in decisions. Depending on what factors contribute to leadership, despotic decisions could either improve decision accuracy or interfere with swarm intelligence. The mechanisms behind leadership are therefore important for understanding its functional significance. In this study, we compared pigeons' relative influence over flock direction to their solo flight characteristics. A pigeon's degree of leadership was predicted by its ground speeds from earlier solo flights, but not by the straightness of its previous solo route. By testing the birds individually after a series of flock flights, we found that leaders had learned straighter homing routes than followers, as we would expect if followers attended less to the landscape and more to conspecifics. We repeated the experiment from three homing sites using multiple independent flocks and found individual consistency in leadership and speed. Our results suggest that the leadership hierarchies observed in previous studies could arise from differences in the birds' typical speeds. Rather than reflecting social preferences that optimize group decisions, leadership may be an inevitable consequence of heterogeneous flight characteristics within self-organized flocks. We also found that leaders learn faster and become better navigators, even if leadership is not initially due to navigational ability. The roles that individuals fall into during collective motion might therefore have far-reaching effects on how they learn about the environment and use social information. PMID:26628007

  8. Job Hunter's Guide Featuring the Seek-a-Job Flock.

    ERIC Educational Resources Information Center

    East Texas State Univ., Commerce. Educational Development and Training Center.

    This job hunter's guide features the "Seek-a-Job Flock," a set of bird characters that humorously help to illustrate job hunting basics. The guide contains five sections: (1) how to find job openings; (2) how to make the interview appointment; (3) how to complete the job application form; (4) how to act during the interview; and (5) how to follow…

  9. Analysis of UF6 breeder reactor power plants

    NASA Technical Reports Server (NTRS)

    Clement, J. D.; Rust, J. H.

    1976-01-01

    Gaseous UF6 fueled breeder reactor design and technical applications of such concepts are summarized. Special attention was given to application in nuclear power plants and to reactor efficiency and safety factors.

  10. 1. Headquarters and Sales Pavilion of the Washington Thoroughbred Breeders ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    1. Headquarters and Sales Pavilion of the Washington Thoroughbred Breeders Association (WTBA). Camera pointed N. (April 1993) - Longacres, WTBA Offices-Sales Pavilion, 1621 Southwest Sixteenth Street, Renton, King County, WA

  11. Tritium release from ceramic breeder materials deposited with noble metals

    NASA Astrophysics Data System (ADS)

    Munakata, Kenzo; Mochizuki, Kazuhiro; Wajima, Takaaki; Wada, Kohei; Hara, Keisuke; Shinozaki, Takashi; Takeishi, Toshiharu; Knitter, Regina; Bekris, Nicolas; Fujii, Toshiyuki; Yamana, Hajimu; Okuno, Kenji

    2011-10-01

    Lithium orthosilicate and lithium aluminate are the candidates of the breeder material of the tritium-breeding blanket. To enhance the rate of tritium release from these breeder materials, 0.2 wt.% of palladium was impregnated into the breeder materials by the incipient wet impregnation method. The lithium orthosilicate and the lithium aluminate pebbles with or without Pd were irradiated in the Kyoto university research reactor, and out-of-pile annealing experiments were performed. When the breeder materials were deposited with a catalytic additive, such as Pd the ratio of the tritium discharged in the molecular form of tritium (HT) increased. It was also found that the amount of the tritium discharged from the lithium orthosilicate pebbles with a catalytic additive at the low temperatures is greater compared with lithium aluminate.

  12. Tritium percolation, convection, and permeation in fusion solid breeder blankets

    SciTech Connect

    Billone, M.C.; Liu, Y.Y.

    1985-01-01

    Models are developed to describe the percolation of released tritium through the breeder interconnected porosity to the purge stream, convection of tritium by the helium purge stream, and leakage or permeation of tritium through the structural material to the primary coolant system. Important parameters in the models are tritium generation rate, breeder microstructure, tritium species in the gas phase, temperatures, tritium diffusivities and permeabilities, and effectiveness of oxide barriers.

  13. Can Bacteriotherapy Using Commercially Available Probiotics, Prebiotics, and Organic Acids Ameliorate the Symptoms Associated With Runting-Stunting Syndrome in Broiler Chickens?

    PubMed

    Mundt, E; Collett, S R; Berghaus, R; Pedroso, A A; Lee, M D; Maurer, J J

    2015-06-01

    Runting-stunting syndrome (RSS) in poultry has been known for more than 40 years, but the precise etiology remains unknown and a licensed vaccine is consequently not currently available. In order to mitigate the symptoms associated with RSS, a series of experiments was performed to investigate whether a combined bacteriotherapeutic treatment consisting of probiotics, prebiotics, and organic acids could influence the outcome of this disease. Initially two groups of commercial broiler chickens were either left uninoculated or inoculated with filtrate from homogenized intestines of RSS-affected broiler chickens. One group from each of these two challenge groups was treated, with a bacteriotherapeutic regimen. After 12 days chickens were euthanatized, the body weight was measured, and duodenal lesions were enumerated. Five consecutive broiler chicken flocks were then raised either on litter from RSS-affected birds or on fresh wood shavings. Treatment had no beneficial effect on the number and severity of intestinal lesions. There appeared to be a significant build-up of RSS agent(s) in poultry litter, with each consecutive flock placement, independent of bacteriotherapeutic treatment, as more individuals exhibited intestinal lesions on built-up litter in RSS-affected houses (28.9% vs. 44%). While treatment did not appear to consistently reduce intestinal lesions, it did significantly improve the mean body weights (P<0.05) and uniformity of 12-day-old chickens placed on reused litter in houses in which RSS-infected birds were previously raised. A combination of litter management and bacteriotherapy may be needed to ameliorate the adverse effects of RSS on intestinal health and body weight in broiler chickens. PMID:26473669

  14. Organic Turkey Flocks: A Reservoir of Streptococcus gallolyticus subspecies gallolyticus.

    PubMed

    Schulz, Jochen; Dumke, Jessika; Hinse, Dennis; Dreier, Jens; Habig, Christin; Kemper, Nicole

    2015-01-01

    Streptococcus gallolyticus subspecies gallolyticus (S. gallolyticus) can colonise the gastrointestinal tract of humans and animals and is known to cause similar infections in both humans and animals. Data about the spread or prevalence in farm animals are missing. In this study, Trypton Soya Agar was modified to a selective medium enabling the isolation and quantification of S. gallolyticus from faecal samples. The bacterium was observed in 82 out of 91 faecal samples obtained from 18 different organic turkey flocks. The prevalence of shedding birds was estimated by the number of positive fresh droppings and reached up to 100% on most farms. Furthermore, for the first time S. gallolyticus was quantified in faeces from poultry flocks. The median of colony forming units (CFU) per gramme faeces was 3.6 x 10(5) CFU/g. Typing of one isolate from each positive faecal sample by multilocus sequence typing delivered 24 sequence types (STs). Most of the isolates belonged to the clonal complex CC58. The same STs of this complex were detected in up to six different flocks. Partly, these flocks were located in various regions and stocked with varying breeding lines. Regarding the biochemical profiles of the same STs from different farms, the results did not contradict a spread of specific STs in the organic turkey production. Moreover, checking the pubMLST database revealed that STs found in this study were also found in other animal species and in humans. The high detection rate and the number of S. gallolyticus in turkey faeces indicate that this bacterium probably belongs to the common microbiota of the gastrointestinal tract of turkeys from organic flocks. Furthermore, the findings of this study support the suggestion of a possible interspecies transmission.

  15. Organic Turkey Flocks: A Reservoir of Streptococcus gallolyticus subspecies gallolyticus

    PubMed Central

    Schulz, Jochen; Dumke, Jessika; Hinse, Dennis; Dreier, Jens; Habig, Christin; Kemper, Nicole

    2015-01-01

    Streptococcus gallolyticus subspecies gallolyticus (S. gallolyticus) can colonise the gastrointestinal tract of humans and animals and is known to cause similar infections in both humans and animals. Data about the spread or prevalence in farm animals are missing. In this study, Trypton Soya Agar was modified to a selective medium enabling the isolation and quantification of S. gallolyticus from faecal samples. The bacterium was observed in 82 out of 91 faecal samples obtained from 18 different organic turkey flocks. The prevalence of shedding birds was estimated by the number of positive fresh droppings and reached up to 100% on most farms. Furthermore, for the first time S. gallolyticus was quantified in faeces from poultry flocks. The median of colony forming units (CFU) per gramme faeces was 3.6 x 105CFU/g. Typing of one isolate from each positive faecal sample by multilocus sequence typing delivered 24 sequence types (STs). Most of the isolates belonged to the clonal complex CC58. The same STs of this complex were detected in up to six different flocks. Partly, these flocks were located in various regions and stocked with varying breeding lines. Regarding the biochemical profiles of the same STs from different farms, the results did not contradict a spread of specific STs in the organic turkey production. Moreover, checking the pubMLST database revealed that STs found in this study were also found in other animal species and in humans. The high detection rate and the number of S. gallolyticus in turkey faeces indicate that this bacterium probably belongs to the common microbiota of the gastrointestinal tract of turkeys from organic flocks. Furthermore, the findings of this study support the suggestion of a possible interspecies transmission. PMID:26657757

  16. Cyclic and Coherent States in Flocks with Topological Distance

    NASA Astrophysics Data System (ADS)

    Bhattacherjee, Biplab; Bhattacharya, Kunal; Manna, Subhrangshu

    2014-01-01

    A simple model of the two dimensional collective motion of a group of mobile agents have been studied. Like birds, these agents travel in open free space where each of them interacts with the first n neighbors determined by the topological distance with a free boundary condition. Using the same prescription for interactions used in the Vicsek model with scalar noise it has been observed that the flock, in absence of the noise, arrives at a number of interesting stationary states. One of the two most prominent states is the `single sink state' where the entire flock travels along the same direction maintaining perfect cohesion and coherence. The other state is the `cyclic state' where every individual agent executes a uniform circular motion, and the correlation among the agents guarantees that the entire flock executes a pulsating dynamics i.e., expands and contracts periodically between a minimum and a maximum size of the flock. We have studied another limiting situation when refreshing rate of the interaction zone is the fastest. In this case the entire flock gets fragmented into smaller clusters of different sizes. On introduction of scalar noise a crossover is observed when the agents cross over from a ballistic motion to a diffusive motion. Expectedly the crossover time is dependent on the strength of the noise η and diverges as η → 0. An even more simpler version of this model has been studied by suppressing the translational degrees of freedom of the agents but retaining their angular motion. Here agents are the spins, placed at the sites of a square lattice with periodic boundary condition. Every spin interacts with its n = 2, 3 or 4 nearest neighbors. In the stationary state the entire spin pattern moves as a whole when interactions are anisotropic with n = 2 and 3; but it is completely frozen when the interaction is isotropic with n=4$. These spin configu

  17. Cyclic and Coherent States in Flocks with Topological Distance

    NASA Astrophysics Data System (ADS)

    Bhattacherjee, Biplab; Bhattacharya, Kunal; Manna, Subhrangshu

    A simple model of the two dimensional collective motion of a group of mobile agents have been studied. Like birds, these agents travel in open free space where each of them interacts with the first n neighbors determined by the topological distance with a free boundary condition. Using the same prescription for interactions used in the Vicsek model with scalar noise it has been observed that the flock, in absence of the noise, arrives at a number of interesting stationary states. One of the two most prominent states is the `single sink state' where the entire flock travels along the same direction maintaining perfect cohesion and coherence. The other state is the `cyclic state' where every individual agent executes a uniform circular motion, and the correlation among the agents guarantees that the entire flock executes a pulsating dynamics i.e., expands and contracts periodically between a minimum and a maximum size of the flock. We have studied another limiting situation when refreshing rate of the interaction zone is the fastest. In this case the entire flock gets fragmented into smaller clusters of different sizes. On introduction of scalar noise a crossover is observed when the agents cross over from a ballistic motion to a diffusive motion. Expectedly the crossover time is dependent on the strength of the noise eta and diverges as eta -> 0. An even more simpler version of this model has been studied by suppressing the translational degrees of freedom of the agents but retaining their angular motion. Here agents are the spins, placed at the sites of a square lattice with periodic boundary condition. Every spin interacts with its n = 2, 3 or 4 nearest neighbors. In the stationary state the entire spin pattern moves as a whole when interactions are anisotropic with n = 2 and 3; but it is completely frozen when the interaction is isotropic with n=4. These spin configu

  18. A Breeder Algorithm for Stellarator Optimization

    NASA Astrophysics Data System (ADS)

    Wang, S.; Ware, A. S.; Hirshman, S. P.; Spong, D. A.

    2003-10-01

    An optimization algorithm that combines the global parameter space search properties of a genetic algorithm (GA) with the local parameter search properties of a Levenberg-Marquardt (LM) algorithm is described. Optimization algorithms used in the design of stellarator configurations are often classified as either global (such as GA and differential evolution algorithm) or local (such as LM). While nonlinear least-squares methods such as LM are effective at minimizing a cost-function based on desirable plasma properties such as quasi-symmetry and ballooning stability, whether or not this is a local or global minimum is unknown. The advantage of evolutionary algorithms such as GA is that they search a wider range of parameter space and are not susceptible to getting stuck in a local minimum of the cost function. Their disadvantage is that in some cases the evolutionary algorithms are ineffective at finding a minimum state. Here, we describe the initial development of the Breeder Algorithm (BA). BA consists of a genetic algorithm outer loop with an inner loop in which each generation is refined using a LM step. Initial results for a quasi-poloidal stellarator optimization will be presented, along with a comparison to existing optimization algorithms.

  19. Fusion breeder: its potential role and prospects

    SciTech Connect

    Lee, J.D.

    1981-01-01

    The fusion breeder is a concept that utilizes 14 MeV neutrons from D + T ..-->.. n(14.1 MeV) + ..cap alpha..(3.5 MeV) fusion reactions to produce more fuel than the tritium (T) needed to sustain the fusion process. This excess fuel production capacity is used to produce fissile material (Pu-239 or U-233) for subsequent use in fission reactors. We are concentrating on a class of blankets we call fission suppressed. The blanket is the region surrounding the fusion plasma in which fusion neutrons interact to produce fuel and heat. The fission-suppressed blanket uses non-fission reactions (mainly (n,2n) or (n,n't)) to generate excess neutrons for the production of net fuel. This is in contrast to the fast fission class of blankets which use (n,fiss) reactions to generate excess neutrons. Fusion reactors with fast fission blankets are commony known as fusion-fission hybrids because they combine fusion and fission in the same device.

  20. Ceramic breeder materials : status and needs.

    SciTech Connect

    Johnson, C.E.

    1998-02-02

    The tritium breeding blanket is one of the most important components of a fusion reactor because it directly involves both energy extraction and tritium production, both of which are critical to fusion power. Because of their overall desirable properties, lithium-containing ceramic solids are recognized as attractive tritium breeding materials for fusion reactor blankets. Indeed, their inherent thermal stability and chemical inertness are significant safety advantages. In numerous in-pile experiments, these materials have performed well, showing good thermal stability and good tritium release characteristics. Tritium release is particularly facile when an argon or helium purge gas containing hydrogen, typically at levels of about 0.1%, is used. However, the addition of hydrogen to the purge gas imposes a penalty when it comes to recovery of the tritium produced in the blanket. In particular, a large amount of hydrogen in the purge gas will necessitate a large multiple-stage tritium purification unit, which could translate into higher costs. Optimizing tritium release while minimizing the amount of hydrogen necessary in the purge gas requires a deeper understanding of the tritium release process, especially the interactions of hydrogen with the surface of the lithium ceramic. This paper reviews the status of ceramic breeder research and highlights several issues and data needs.

  1. Broiler Growers. People on the Farm.

    ERIC Educational Resources Information Center

    Department of Agriculture, Washington, DC. Office of Governmental and Public Affairs.

    This booklet, one in a series about life on modern farms, describes the daily life of the Maurice Layton family, broiler (chicken) growers in Mississippi. Beginning with early morning chores, the booklet traces the family's activities through a typical day while explaining how a broiler farm operates. Although the booklet focuses on broiler…

  2. Breast muscle tissue characteristics in growing broilers

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Muscle cell development in broilers influences growth rate, breast meat yield, and meat quality. The objective of this study was to characterize muscle tissue changes in breast muscles from two commercial lines of broilers from 21 to 56 days of age. The experiment was designed as a 2×2×6 factorial...

  3. Multiple Applications of Sodium Bisulfate to Broiler Litter Affect Ammonia Release and Litter Properties.

    PubMed

    Hunolt, Alicia E; Maguire, Rory O; Ogejo, Jactone A; Badgley, Brian D; Frame, W Hunter; Reiter, Mark S

    2015-11-01

    Ammonia (NH) emissions from animal manures can cause air and water quality problems. Poultry litter treatment (PLT, sodium bisulfate; Jones-Hamilton Co.) is an acidic amendment that is applied to litter in poultry houses to decrease NH emissions, but currently it can only be applied once before birds are placed in the houses. This project analyzed the effect of multiple PLT applications on litter properties and NH release. Volatility chambers were used to compare multiple, single, and no application of PLT to poultry litter, all with and without fresh manure applications. A field component consisted of two commercial broiler houses: one had a single, preflock PLT application, while the other received PLT reapplications during the flock using an overhead application system. In the volatility chambers, single and reapplied PLT caused greater litter moisture and lower litter pH and , relative to no PLT. After 14 d, NH released from litter treated with reapplied PLT was significantly less than litter with both single and no applications. Furthermore, total N in litter was greatest in litter treated with reapplied PLT, increasing its fertilizer value. In the commercial poultry houses, PLT reapplication led to a temporary decrease in litter pH and , but these effects did not last because of continued bird excretion. Although one preflock PLT application is currently used as a successful strategy to control NH during early flock growth, repeat PLT application using the overhead reapplication system was not successful because of problems with the reapplication system and litter moisture concerns. PMID:26641342

  4. Design of the injection beamline for the Californium Rare Isotope Breeder Upgrade electron beam ion source for charge breeder

    SciTech Connect

    Dickerson C. A.; Pikin A.; Mustapha, B.; Kondrashev, S.; Ostroumov, P.N.; Savard, S.; Levand, A.

    2012-02-07

    The design of the ion injection line connecting the electron beam ion source (EBIS) charge breeder and the Californium Rare Isotope Breeder Upgrade radio frequency quadrupole cooler-buncher at the Argonne Tandem Linear Accelerator System was investigated with particle tracking simulations. The injection line was configured to accommodate several differential pumping sections, individual optical components were optimized to minimize emittance growth, and the ion beam parameters were matched with the EBIS electron beam acceptance to minimize losses upon injection.

  5. Design of the injection beamline for the Californium Rare Isotope Breeder Upgrade electron beam ion source charge breeder

    SciTech Connect

    Dickerson, C. A.; Mustapha, B.; Kondrashev, S.; Ostroumov, P. N.; Savard, G.; Levand, A.; Pikin, A.

    2012-02-15

    The design of the ion injection line connecting the electron beam ion source (EBIS) charge breeder and the Californium Rare Isotope Breeder Upgrade radio frequency quadrupole cooler-buncher at the Argonne Tandem Linear Accelerator System was investigated with particle tracking simulations. The injection line was configured to accommodate several differential pumping sections, individual optical components were optimized to minimize emittance growth, and the ion beam parameters were matched with the EBIS electron beam acceptance to minimize losses upon injection.

  6. Design of the injection beamline for the Californium Rare Isotope Breeder Upgrade electron beam ion source charge breeder.

    PubMed

    Dickerson, C A; Mustapha, B; Kondrashev, S; Ostroumov, P N; Savard, G; Levand, A; Pikin, A

    2012-02-01

    The design of the ion injection line connecting the electron beam ion source (EBIS) charge breeder and the Californium Rare Isotope Breeder Upgrade radio frequency quadrupole cooler-buncher at the Argonne Tandem Linear Accelerator System was investigated with particle tracking simulations. The injection line was configured to accommodate several differential pumping sections, individual optical components were optimized to minimize emittance growth, and the ion beam parameters were matched with the EBIS electron beam acceptance to minimize losses upon injection.

  7. Development of electron beam ion source charge breeder for rare isotopes at Californium Rare Isotope Breeder Upgrade.

    PubMed

    Kondrashev, S; Dickerson, C; Levand, A; Ostroumov, P N; Pardo, R C; Savard, G; Vondrasek, R; Alessi, J; Beebe, E; Pikin, A; Kuznetsov, G I; Batazova, M A

    2012-02-01

    Recently, the Californium Rare Isotope Breeder Upgrade (CARIBU) to the Argonne Tandem Linac Accelerator System (ATLAS) was commissioned and became available for production of rare isotopes. Currently, an electron cyclotron resonance ion source is used as a charge breeder for CARIBU beams. To further increase the intensity and improve the purity of neutron-rich ion beams accelerated by ATLAS, we are developing a high-efficiency charge breeder for CARIBU based on an electron beam ion source (EBIS). The CARIBU EBIS charge breeder will utilize the state-of-the-art EBIS technology recently developed at Brookhaven National Laboratory (BNL). The electron beam current density in the CARIBU EBIS trap will be significantly higher than that in existing operational charge-state breeders based on the EBIS concept. The design of the CARIBU EBIS charge breeder is nearly complete. Long-lead components of the EBIS such as a 6-T superconducting solenoid and an electron gun have been ordered with the delivery schedule in the fall of 2011. Measurements of expected breeding efficiency using the BNL Test EBIS have been performed using a Cs(+) surface ionization ion source for external injection in pulsed mode. In these experiments we have achieved ∼70% injection∕extraction efficiency and breeding efficiency into the most abundant charge state of ∼17%.

  8. Development of electron beam ion source charge breeder for rare isotopes at Californium Rare Isotope Breeder Upgradea)

    NASA Astrophysics Data System (ADS)

    Kondrashev, S.; Dickerson, C.; Levand, A.; Ostroumov, P. N.; Pardo, R. C.; Savard, G.; Vondrasek, R.; Alessi, J.; Beebe, E.; Pikin, A.; Kuznetsov, G. I.; Batazova, M. A.

    2012-02-01

    Recently, the Californium Rare Isotope Breeder Upgrade (CARIBU) to the Argonne Tandem Linac Accelerator System (ATLAS) was commissioned and became available for production of rare isotopes. Currently, an electron cyclotron resonance ion source is used as a charge breeder for CARIBU beams. To further increase the intensity and improve the purity of neutron-rich ion beams accelerated by ATLAS, we are developing a high-efficiency charge breeder for CARIBU based on an electron beam ion source (EBIS). The CARIBU EBIS charge breeder will utilize the state-of-the-art EBIS technology recently developed at Brookhaven National Laboratory (BNL). The electron beam current density in the CARIBU EBIS trap will be significantly higher than that in existing operational charge-state breeders based on the EBIS concept. The design of the CARIBU EBIS charge breeder is nearly complete. Long-lead components of the EBIS such as a 6-T superconducting solenoid and an electron gun have been ordered with the delivery schedule in the fall of 2011. Measurements of expected breeding efficiency using the BNL Test EBIS have been performed using a Cs+ surface ionization ion source for external injection in pulsed mode. In these experiments we have achieved ˜70% injection/extraction efficiency and breeding efficiency into the most abundant charge state of ˜17%.

  9. Development of electron beam ion source charge breeder for rare isotopes at Californium Rare Isotope Breeder Upgrade

    SciTech Connect

    Kondrashev, S.; Dickerson, C.; Levand, A.; Ostroumov, P. N.; Pardo, R. C.; Savard, G.; Vondrasek, R.; Alessi, J.; Beebe, E.; Pikin, A.; Kuznetsov, G. I.; Batazova, M. A.

    2012-02-15

    Recently, the Californium Rare Isotope Breeder Upgrade (CARIBU) to the Argonne Tandem Linac Accelerator System (ATLAS) was commissioned and became available for production of rare isotopes. Currently, an electron cyclotron resonance ion source is used as a charge breeder for CARIBU beams. To further increase the intensity and improve the purity of neutron-rich ion beams accelerated by ATLAS, we are developing a high-efficiency charge breeder for CARIBU based on an electron beam ion source (EBIS). The CARIBU EBIS charge breeder will utilize the state-of-the-art EBIS technology recently developed at Brookhaven National Laboratory (BNL). The electron beam current density in the CARIBU EBIS trap will be significantly higher than that in existing operational charge-state breeders based on the EBIS concept. The design of the CARIBU EBIS charge breeder is nearly complete. Long-lead components of the EBIS such as a 6-T superconducting solenoid and an electron gun have been ordered with the delivery schedule in the fall of 2011. Measurements of expected breeding efficiency using the BNL Test EBIS have been performed using a Cs{sup +} surface ionization ion source for external injection in pulsed mode. In these experiments we have achieved {approx}70% injection/extraction efficiency and breeding efficiency into the most abundant charge state of {approx}17%.

  10. Development of electron beam ion source charge breeder for rare isotopes at Californium Rare Isotope Breeder Upgrade

    SciTech Connect

    Kondrashev S.; Alessi J.; Dickerson, C.; Levand, A.; Ostroumov, P.N.; Pardo, R.C.; Savard, G.; Vondrasek, R.; Beebe, E.; Pikin, A.; Kuznetsov, G.I.; Batazova, M.A.

    2012-02-03

    Recently, the Californium Rare Isotope Breeder Upgrade (CARIBU) to the Argonne Tandem Linac Accelerator System (ATLAS) was commissioned and became available for production of rare isotopes. Currently, an electron cyclotron resonance ion source is used as a charge breeder for CARIBU beams. To further increase the intensity and improve the purity of neutron-rich ion beams accelerated by ATLAS, we are developing a high-efficiency charge breeder for CARIBU based on an electron beam ion source (EBIS). The CARIBU EBIS charge breeder will utilize the state-of-the-art EBIS technology recently developed at Brookhaven National Laboratory (BNL). The electron beam current density in the CARIBU EBIS trap will be significantly higher than that in existing operational charge-state breeders based on the EBIS concept. The design of the CARIBU EBIS charge breeder is nearly complete. Long-lead components of the EBIS such as a 6-T superconducting solenoid and an electron gun have been ordered with the delivery schedule in the fall of 2011. Measurements of expected breeding efficiency using the BNL Test EBIS have been performed using a Cs{sup +} surface ionization ion source for external injection in pulsed mode. In these experiments we have achieved {approx}70% injection/extraction efficiency and breeding efficiency into the most abundant charge state of {approx}17%.

  11. Investigation of enrofloxacin residues in broiler tissues using ELISA and LC-MS/MS.

    PubMed

    Panzenhagen, Pedro Henrique N; Aguiar, Waldemir S; Gouvêa, Raquel; de Oliveira, Andréa M G; Barreto, Fabiano; Pereira, Virgínia L A; Aquino, Maria Helena C

    2016-01-01

    This study investigated the efficiency of an enrofloxacin ELISA test kit to detect the presence of enrofloxacin residues in broiler tissues compared with LC-MS/MS. Broiler tissues from 72 samples consisting of 60 breast muscle, six pools of livers (500 g each) and six pools of kidneys (500 g each) were obtained from six different slaughterhouses. Breast muscle from 10 carcasses and pools of livers and kidneys from approximately 200 carcasses of the same flock were collected from each slaughterhouse. ELISA and HPLC were used to identify and quantify the contamination of the samples with enrofloxacin. A total of 72% of the analysed samples contained enrofloxacin residues detected by the ELISA and 22.2% were detected by LC-MS/MS. The mean values of enrofloxacin contamination found in chicken breast by ELISA and HPLC were 8.63 and 12.25 μg kg(-1), respectively. None of the samples exceeded the maximum limit of 100 μg kg(-1) by both methods set by the European Union as well as the Brazilian Agriculture Ministry. All positive samples for enrofloxacin residues detected by LC-MS/MS were also positive by ELISA. These data confirm the efficiency of the ELISA test, and suggest its use as a screening method for enrofloxacin residues in poultry tissues due to its quick results, low price and ease of applicability.

  12. Polymerase chain reaction detection of naturally occurring Campylobacter in commercial broiler chicken embryos.

    PubMed

    Hiett, K L; Cox, N A; Rothrock, M J

    2013-04-01

    Campylobacter, a foodborne pathogen closely associated with poultry, is recognized as a leading bacterial etiologic agent of human gastroenteritis in the United States. In this investigation, 2 trials were performed where tissues from 7-, 14/15-, and 19-d-old commercial broiler chicken embryos were tested for the presence of Campylobacter using both culturing methodology and PCR. Conventional culturing methods failed to detect Campylobacter from any samples tested during this investigation. Using a set of primers specific for the Campylobacter flagellinA short variable region (flaA SVR), Campylobacter DNA was amplified in 100, 80, and 100% of gastrointestinal tracts from 7-, 15-, and 19-d-old embryos, respectively, in the first trial. Similarly, Campylobacter DNA was detected in 100, 70, and 60% of gastrointestinal tracts of 7-, 14-, and 18-d-old embryos, respectively, in the second trial. In both trials, yolk sac, albumin, and liver/gallbladder samples from 19-d-old embryos all failed to produce amplicons indicative of Campylobacter DNA. Subsequent DNA sequence analyses of the flaA SVR PCR products were consistent with the amplicon arising from Campylobacter. Although a determination of whether the Campylobacter was living or dead within the embryos could not be made, these results demonstrate that Campylobacter-specific DNA is present within the gastrointestinal tract of broiler chicken embryos; however, the means by which it is present and the relative contribution to subsequent Campylobacter contamination of poultry flocks requires further investigation.

  13. Plant and soil intake by organic broilers reared in tree- or grass-covered plots as determined by means of n-alkanes and of acid-insoluble ash.

    PubMed

    Jurjanz, S; Germain, K; Juin, H; Jondreville, C

    2015-05-01

    Free-range birds such as organic broilers may ingest soil and plants during exploration. The estimation of such intakes is of great interest to quantify possible nutritional supplies and also to evaluate the risk of exposure to parasites or to environmental contaminants. Marker-based techniques are now available and would allow to quantify plant and, especially, soil intake in free-range birds, and this quantification was the aim of this study. Methodologically, the proportion of plants in diet intake was determined first using a method based on n-alkanes. Subsequently, the fraction of soil in the total intake was estimated with a second marker, acid-insoluble ash. This approach was carried out to estimate ingested amounts of plants and soil for five successive flocks of organic broilers, exploring grass-covered yards or those under trees, at two time points for each yard: 51 and 64 days of age. Each factor combination (yard type×period=flock number×age) was repeated on two different yards of 750 broilers each. The birds' plant intake varied widely, especially on grass-covered yards. The proportion of plant intake was significantly higher on grass-covered plots than under trees and was also affected, but to a lesser extent, by age or flock number. The ingestion of plants would generally not exceed 11 g of DM daily, except two extreme outliers of nearly 30 g. The daily plant intake under trees tended to be lower and never exceeded 7 g of DM. The amount of ingested plants increased significantly for spring flocks. It increased slightly but significantly with age. The proportion of ingested soil was significantly higher under trees than on grass-covered yards. Dry soil intake was generally low with not more than 3 g per day. Only in adverse conditions - that is, older birds exploring yards under trees in winter - soil intake reached the extreme value of nearly 5 g. Broilers on yards under trees ingested significantly more soil than on grass-covered yards with least

  14. Status of the solid breeder materials database

    SciTech Connect

    Billone, M.C.; Dienst, W.; Lorenzetto, P.; Noda, K.; Roux, N.

    1995-01-01

    The databases for solid breeder ceramics (Li{sub 2}O, Li{sub 4}SiO{sub 4}, Li{sub 2}ZrO{sub 3}, and LiAlO{sub 2}) and beryllium multiplier material were critically reviewed and evaluated as part of the ITER/CDA design effort (1988-1990). The results have been documented in a detailed technical report. Emphasis was placed on the physical, thermal, mechanical, chemical stability/compatibility, tritium retention/release, and radiation stability properties which are needed to assess the performance of these materials in a fusion reactor environment. Materials properties correlations were selected for use in design analysis, and ranges for input parameters (e.g., temperature, porosity, etc.) were established. Also, areas for future research and development in blanket materials technology were highlighted and prioritized. For Li{sub 2}O, the most significant increase in the database has come in the area of tritium retention as a function of operating temperature and purge flow composition. The database for postirradiation inventory from purged in-reactor samples has increased from four points to 20 points. These new data have allowed an improvement in understanding and modeling, as well as better interpretation of the results of laboratory annealing studies on unirradiated and irradiated material. In the case of Li{sub 2}ZrO{sub 3}, relatively little data were available on the sensitivity of the mechanical properties of this ternary ceramic to microstructure and moisture content. The increase in the database for this material has allowed not only better characterization of its properties, but also optimization of fabrication parameters to improve its performance. Some additional data are also available for the other two ternary ceramics to aid in the characterization of their performance. In particular, the thermal performance of these materials, as well as beryllium, in packed-bed form has been measured and characterized.

  15. A quantitative trait locus for ascites on chromosome 9 in broiler chicken lines

    PubMed Central

    Krishnamoorthy, Sriram; Smith, Candace D.; Al-Rubaye, Adnan A.; Erf, Gisela F.; Wideman, Robert F.; Anthony, Nicholas B.; Rhoads, Douglas D.

    2014-01-01

    A genome-wide SNP survey was used to identify chromosomal regions that showed linkage disequilibrium with respect to ascites susceptibility and ventricular hypertrophy in an F2 cross between previously described ascites-resistant and -susceptible lines. Variable number tandem repeats were used to obtain genotype data to further characterize these regions. A region on chromosome 9 (12 to 13 Mbp in 2011 assembly) shows association with ascites in the ascites lines and in several commercial broiler breeder lines with a significant sex effect. There are 2 candidate genes, AGTR1 (an angiotensin II type 1 receptor) and UTS2D (urotensin 2 domain containing), in this region that have been associated with hypertension and hypoxic response in mammals. PMID:24570451

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

    USGS Publications Warehouse

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

    1994-01-01

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

  17. Spatio-Temporal Structure of Hooded Gull Flocks

    PubMed Central

    Yomosa, Makoto; Mizuguchi, Tsuyoshi; Hayakawa, Yoshinori

    2013-01-01

    We analyzed the spatio-temporal structure of hooded gull flocks with a portable stereo camera system. The 3-dimensional positions of individuals were reconstructed from pairs of videos. The motions of each individual were analyzed, and both gliding and flapping motions were quantified based on the velocity time series. We analyzed the distributions of the nearest neighbor’s position in terms of coordinates based on each individual’s motion. The obtained results were consistent with the aerodynamic interaction between individuals. We characterized the leader-follower relationship between individuals by a delay time to mimic the direction of a motion. A relation between the delay time and a relative position was analyzed quantitatively, which suggested the basic properties of the formation flight that maintains order in the flock. PMID:24339960

  18. SEROVARS AND ANTIMICROBIAL RESISTANCE OF Salmonella spp. ISOLATED FROM TURKEY AND BROILER CARCASSES IN SOUTHERN BRAZIL BETWEEN 2004 AND 2006.

    PubMed

    Palmeira, Andre; Santos, Luciana Ruschel dos; Borsoi, Anderlise; Rodrigues, Laura Beatriz; Calasans, Max; Nascimento, Vladimir Pinheiro do

    2016-01-01

    Salmonella spp. causes diseases in fowls, when species-specific serovars (Salmonella Pullorum and S.Gallinarum) are present in flocks, and public health problems, when non-typhoid serovars are isolated, as well as possible bacterial resistance induced by the preventive and therapeutic use of antimicrobials in animal production. This study describes the serovars and bacterial resistance of 280 Salmonella spp. strains isolated from turkey and broiler carcasses in Southern Brazil between 2004 and 2006. Salmonella Enteritidis was the most prevalent serovar (55.7%), followed by Heidelberg (5.0%), Agona (4.3%), Bredeney (3.9%), Hadar (3.2%), and Typhimurium (2.9%). Tennessee and S. Enterica subspecies enterica(O: 4.5) were isolated only in turkeys, and Hadar (18.6%) was the most prevalent serovar in this species. Antimicrobial susceptibility tests were performed in 178 isolates (43 from turkeys and 135 from broilers). All isolates were sensitive to amoxicillin + clavulanic acid, polymyxin B, ciprofloxacin, and norfloxacin, and were resistant to bacitracin and penicillin. Broiler carcass isolates showed resistance to nalidixic acid (48.9%), nitrofurantoin (34.3%), neomycin (9.6%), tetracycline (5.2%), and kanamycin (8.9%); and turkey carcass isolates were resistant to nalidixic acid (62.8%), tetracycline (34.9%), and neomycin (30.2%), with a significant difference in turkeys when compared to broiler carcass isolates. These results indicate the need for judicious use of antimicrobials in livestock production, given that the serovars identified are potential causes of food poisoning. PMID:27007562

  19. SEROVARS AND ANTIMICROBIAL RESISTANCE OF Salmonella spp. ISOLATED FROM TURKEY AND BROILER CARCASSES IN SOUTHERN BRAZIL BETWEEN 2004 AND 2006

    PubMed Central

    PALMEIRA, Andre; dos SANTOS, Luciana Ruschel; BORSOI, Anderlise; RODRIGUES, Laura Beatriz; CALASANS, Max; do NASCIMENTO, Vladimir Pinheiro

    2016-01-01

    Salmonella spp. causes diseases in fowls, when species-specific serovars (Salmonella Pullorum and S.Gallinarum) are present in flocks, and public health problems, when non-typhoid serovars are isolated, as well as possible bacterial resistance induced by the preventive and therapeutic use of antimicrobials in animal production. This study describes the serovars and bacterial resistance of 280Salmonella spp. strains isolated from turkey and broiler carcasses in Southern Brazil between 2004 and 2006. SalmonellaEnteritidis was the most prevalent serovar (55.7%), followed by Heidelberg (5.0%), Agona (4.3%), Bredeney (3.9%), Hadar (3.2%), and Typhimurium (2.9%). Tennessee and S. Enterica subspecies enterica(O: 4.5) were isolated only in turkeys, and Hadar (18.6%) was the most prevalent serovar in this species. Antimicrobial susceptibility tests were performed in 178 isolates (43 from turkeys and 135 from broilers). All isolates were sensitive to amoxicillin + clavulanic acid, polymyxin B, ciprofloxacin, and norfloxacin, and were resistant to bacitracin and penicillin. Broiler carcass isolates showed resistance to nalidixic acid (48.9%), nitrofurantoin (34.3%), neomycin (9.6%), tetracycline (5.2%), and kanamycin (8.9%); and turkey carcass isolates were resistant to nalidixic acid (62.8%), tetracycline (34.9%), and neomycin (30.2%), with a significant difference in turkeys when compared to broiler carcass isolates. These results indicate the need for judicious use of antimicrobials in livestock production, given that the serovars identified are potential causes of food poisoning. PMID:27007562

  20. Emissions of methane and nitrous oxide from outdoor-stored broiler litter using tunable-diode laser spectroscopy

    NASA Astrophysics Data System (ADS)

    de Wit, William Harrison

    Handling and storage of a variety of types of agricultural wastes results in the formation and release of nitrous oxide (N2O) and methane (CH4) gases to the atmosphere. These gases contribute to climate change through the greenhouse effect. Few studies have examined evolution of these gases from stored poultry litter in North America. Although N 2O is a by-product of nitrification, it is largely produced as an intermediate product of denitrification and is produced most intensely when both aerobic and anaerobic conditions are present. CH4 emissions, however, are typically associated with anaerobic reactions. Outdoor storage of broiler litter provides an excellent media for which both aerobic and anaerobic zones can coexist, particularly when the litter is of varying ages from multiple broiler flocks (cycles). It provides a large amount of nitrogen for bacterial nitrification/denitrification processes as well as Carbon to support anaerobic bacterial fermentation. The objective of the study was to quantify N 2O and CH4 emissions for broiler litter stored in an uncovered, outdoor bunker by conducting small-scale dynamic flux chamber studies and full-scale field experiments. The field experiments used a modified micrometeorological mass balance approach to monitor emissions from stored broiler litter in a three-walled concrete bunker. Atmospheric concentrations of N2O and CH4 were measured using tunable-diode laser spectroscopy. Field experiments over the course of approximately four months yielded average emission rates of 14+/-17mug m-2 s -1 and 84+/-61 mug m-2 s-1 for N2O and CH4 respectively that agreed well with the trends of emission rates observed in the dynamic flux chamber experiments. The primary drivers of emissions of both CH4 and N2O appeared to be temperature and moisture content while organic carbon and organic nitrogen (loss on ignition, nitrate concentrations) contents were also important factors.

  1. SEROVARS AND ANTIMICROBIAL RESISTANCE OF Salmonella spp. ISOLATED FROM TURKEY AND BROILER CARCASSES IN SOUTHERN BRAZIL BETWEEN 2004 AND 2006.

    PubMed

    Palmeira, Andre; Santos, Luciana Ruschel dos; Borsoi, Anderlise; Rodrigues, Laura Beatriz; Calasans, Max; Nascimento, Vladimir Pinheiro do

    2016-01-01

    Salmonella spp. causes diseases in fowls, when species-specific serovars (Salmonella Pullorum and S.Gallinarum) are present in flocks, and public health problems, when non-typhoid serovars are isolated, as well as possible bacterial resistance induced by the preventive and therapeutic use of antimicrobials in animal production. This study describes the serovars and bacterial resistance of 280 Salmonella spp. strains isolated from turkey and broiler carcasses in Southern Brazil between 2004 and 2006. Salmonella Enteritidis was the most prevalent serovar (55.7%), followed by Heidelberg (5.0%), Agona (4.3%), Bredeney (3.9%), Hadar (3.2%), and Typhimurium (2.9%). Tennessee and S. Enterica subspecies enterica(O: 4.5) were isolated only in turkeys, and Hadar (18.6%) was the most prevalent serovar in this species. Antimicrobial susceptibility tests were performed in 178 isolates (43 from turkeys and 135 from broilers). All isolates were sensitive to amoxicillin + clavulanic acid, polymyxin B, ciprofloxacin, and norfloxacin, and were resistant to bacitracin and penicillin. Broiler carcass isolates showed resistance to nalidixic acid (48.9%), nitrofurantoin (34.3%), neomycin (9.6%), tetracycline (5.2%), and kanamycin (8.9%); and turkey carcass isolates were resistant to nalidixic acid (62.8%), tetracycline (34.9%), and neomycin (30.2%), with a significant difference in turkeys when compared to broiler carcass isolates. These results indicate the need for judicious use of antimicrobials in livestock production, given that the serovars identified are potential causes of food poisoning.

  2. Relevance of metric-free interactions in flocking phenomena.

    PubMed

    Ginelli, Francesco; Chaté, Hugues

    2010-10-15

    We show that the collective properties of self-propelled particles aligning with their topological (Voronoi) neighbors are qualitatively different from those of usual models where metric interaction ranges are used. This relevance of metric-free interactions, shown in a minimal setting, indicate that realistic models for the cohesive motion of cells, bird flocks, and fish schools may have to incorporate them, as suggested by recent observations. PMID:21231019

  3. Flocking-based Document Clustering on the Graphics Processing Unit

    SciTech Connect

    Cui, Xiaohui; Potok, Thomas E; Patton, Robert M; ST Charles, Jesse Lee

    2008-01-01

    Abstract?Analyzing and grouping documents by content is a complex problem. One explored method of solving this problem borrows from nature, imitating the flocking behavior of birds. Each bird represents a single document and flies toward other documents that are similar to it. One limitation of this method of document clustering is its complexity O(n2). As the number of documents grows, it becomes increasingly difficult to receive results in a reasonable amount of time. However, flocking behavior, along with most naturally inspired algorithms such as ant colony optimization and particle swarm optimization, are highly parallel and have found increased performance on expensive cluster computers. In the last few years, the graphics processing unit (GPU) has received attention for its ability to solve highly-parallel and semi-parallel problems much faster than the traditional sequential processor. Some applications see a huge increase in performance on this new platform. The cost of these high-performance devices is also marginal when compared with the price of cluster machines. In this paper, we have conducted research to exploit this architecture and apply its strengths to the document flocking problem. Our results highlight the potential benefit the GPU brings to all naturally inspired algorithms. Using the CUDA platform from NIVIDA? we developed a document flocking implementation to be run on the NIVIDA?GEFORCE 8800. Additionally, we developed a similar but sequential implementation of the same algorithm to be run on a desktop CPU. We tested the performance of each on groups of news articles ranging in size from 200 to 3000 documents. The results of these tests were very significant. Performance gains ranged from three to nearly five times improvement of the GPU over the CPU implementation. This dramatic improvement in runtime makes the GPU a potentially revolutionary platform for document clustering algorithms.

  4. Relevance of Metric-Free Interactions in Flocking Phenomena

    NASA Astrophysics Data System (ADS)

    Ginelli, Francesco; Chaté, Hugues

    2010-10-01

    We show that the collective properties of self-propelled particles aligning with their topological (Voronoi) neighbors are qualitatively different from those of usual models where metric interaction ranges are used. This relevance of metric-free interactions, shown in a minimal setting, indicate that realistic models for the cohesive motion of cells, bird flocks, and fish schools may have to incorporate them, as suggested by recent observations.

  5. Silent Flocks: Constraints on Signal Propagation Across Biological Groups

    NASA Astrophysics Data System (ADS)

    Cavagna, Andrea; Giardina, Irene; Grigera, Tomas S.; Jelic, Asja; Levine, Dov; Ramaswamy, Sriram; Viale, Massimiliano

    2015-05-01

    Experiments find coherent information transfer through biological groups on length and time scales distinctly below those on which asymptotically correct hydrodynamic theories apply. We present here a new continuum theory of collective motion coupling the velocity and density fields of Toner and Tu to the inertial spin field recently introduced to describe information propagation in natural flocks of birds. The long-wavelength limit of the new equations reproduces the Toner-Tu theory, while at shorter wavelengths (or, equivalently, smaller damping), spin fluctuations dominate over density fluctuations, and second-sound propagation of the kind observed in real flocks emerges. We study the dispersion relation of the new theory and find that when the speed of second sound is large, a gap in momentum space sharply separates first- from second-sound modes. This gap implies the existence of silent flocks, namely, of medium-sized systems across which information cannot propagate in a linear and underdamped way, either under the form of orientational fluctuations or under that of density fluctuations, making it hard for the group to achieve coordination.

  6. Silent flocks: constraints on signal propagation across biological groups.

    PubMed

    Cavagna, Andrea; Giardina, Irene; Grigera, Tomas S; Jelic, Asja; Levine, Dov; Ramaswamy, Sriram; Viale, Massimiliano

    2015-05-29

    Experiments find coherent information transfer through biological groups on length and time scales distinctly below those on which asymptotically correct hydrodynamic theories apply. We present here a new continuum theory of collective motion coupling the velocity and density fields of Toner and Tu to the inertial spin field recently introduced to describe information propagation in natural flocks of birds. The long-wavelength limit of the new equations reproduces the Toner-Tu theory, while at shorter wavelengths (or, equivalently, smaller damping), spin fluctuations dominate over density fluctuations, and second-sound propagation of the kind observed in real flocks emerges. We study the dispersion relation of the new theory and find that when the speed of second sound is large, a gap in momentum space sharply separates first- from second-sound modes. This gap implies the existence of silent flocks, namely, of medium-sized systems across which information cannot propagate in a linear and underdamped way, either under the form of orientational fluctuations or under that of density fluctuations, making it hard for the group to achieve coordination.

  7. Risk factors associated with the colonization of Ontario layer chicken flocks with Brachyspira species.

    PubMed

    Medhanie, Genet A; McEwen, Scott A; Weber, Lloyd; Sanei, Babak; Cooley, Leanne; Houghton, Scott; Slavic, Durda; Guerin, Michele T

    2013-05-01

    Brachyspira species are frequent colonizers of the gastrointestinal tract in a variety of domestic animals, including birds. In chickens, Brachyspira species are associated with a clinical condition known as avian intestinal spirochetosis (AIS), a disease characterized by chronic diarrhoea, weight loss, low egg production, and faecal-stained eggs. The purpose of this study was to identify risk factors associated with the presence of Brachyspira species in Ontario layer chicken flocks. Pooled faecal samples were collected from 89 flocks from 58 farms between August 2010 and February 2011; 52 flocks were classified as dirty flocks (history of downgrades for dirty eggs) and 37 were classified as clean flocks (no history of downgrades for dirty eggs). A questionnaire related to management, biosecurity practices, and antimicrobial use was administered prior to sample collection. Using real-time polymerase chain reaction; 63.5% of the dirty flocks and 24.3% of the clean flocks were positive for Brachyspira species. A logistic regression model with a random effect for farm showed that the odds of Brachyspira species for flocks ≥ 60 weeks of age were higher than for flocks ≤ 34 weeks (OR=9.3; P=0.014). The odds of Brachyspira species in flocks housed in A-frame cages with manure curtains (OR=20.0; P=0.002) and flocks from multi-age farms (OR=8.5; P=0.001) were higher than for flocks in cage-stacked houses and from single-age farms, respectively. The odds of Brachyspira species for flocks housed in barns ≥ 30 years old was lower than for flocks housed in barns ≤ 14 years old (OR=0.1; P=0.002). The calculated intra-class correlation coefficient was 5.6 × 10(-14); the notably low proportion of variation among farms after the fixed effects were included in the model suggests that the farm-level variable (multi-age farm) included in the final model accounted for most of the farm-to-farm variation in Brachyspira presence. Therefore, it is recommended that strict

  8. 21 CFR 520.2184 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) Conditions of use. It is used in the drinking water of broilers, breeder flocks, and replacement chickens as.... Administer in drinking water for 3 days as sole source of drinking water and sulfonamide medication; withdraw... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2184...

  9. 21 CFR 520.2184 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) Conditions of use. It is used in the drinking water of broilers, breeder flocks, and replacement chickens as.... Administer in drinking water for 3 days as sole source of drinking water and sulfonamide medication; withdraw... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2184...

  10. 21 CFR 520.2184 - Sodium sulfachloropyrazine monohydrate.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...) Conditions of use. It is used in the drinking water of broilers, breeder flocks, and replacement chickens as.... Administer in drinking water for 3 days as sole source of drinking water and sulfonamide medication; withdraw... (CONTINUED) ANIMAL DRUGS, FEEDS, AND RELATED PRODUCTS ORAL DOSAGE FORM NEW ANIMAL DRUGS § 520.2184...

  11. Laser fusion driven breeder design study. Final report

    SciTech Connect

    Berwald, D.H.; Massey, J.V.

    1980-12-01

    The results of the Laser Fusion Breeder Design Study are given. This information primarily relates to the conceptual design of an inertial confinement fusion (ICF) breeder reactor (or fusion-fission hybrid) based upon the HYLIFE liquid metal wall protection concept developed at Lawrence Livermore National Laboratory. The blanket design for this breeder is optimized to both reduce fissions and maximize the production of fissile fuel for subsequent use in conventional light water reactors (LWRs). When the suppressed fission blanket is compared with its fast fission counterparts, a minimal fission rate in the blanket results in a unique reactor safety advantage for this concept with respect to reduced radioactive inventory and reduced fission product decay afterheat in the event of a loss-of-coolant-accident.

  12. Effect of organic acids in drinking water for young broilers on Campylobacter infection, volatile fatty acid production, gut microflora and histological cell changes.

    PubMed

    Chaveerach, P; Keuzenkamp, D A; Lipman, L J A; Van Knapen, F

    2004-03-01

    Water is a prominent vehicle for Campylobacter spread throughout a chicken flock. The aim of this study was to evaluate the effect of organic acids administered through the drinking water, as a decontamination method, on gut microflora and the development of lesions in the gastrointestinal tracts of young broilers inoculated with 2 different doses of Campylobacter. The results revealed that most of the chickens were infected with Campylobacter at the end of the experiment. The drinking water was free of Campylobacter throughout the study. No difference of volatile fatty acid levels between treatment and control groups was observed in the crop and cecal contents. In the cecal contents, the total aerobic bacteria numbers were significantly higher in the treatment groups compared with the control groups (P < 0.01 and P < 0.04, respectively). Moreover, no damaged epithelial cells were observed in the chicken gut due to consumption of acidified drinking water. Acidified drinking water could therefore play a crucial role in a biosecurity strategy of preventing Campylobacter spread via drinking water in broiler flocks.

  13. Campylobacter colonization and proliferation in the broiler chicken upon natural field challenge is not affected by the bird growth rate or breed.

    PubMed

    Gormley, Fraser J; Bailey, Richard A; Watson, Kellie A; McAdam, Jim; Avendaño, Santiago; Stanley, William A; Koerhuis, Alfons N M

    2014-11-01

    The zoonotic association between Campylobacter bacteria in poultry and humans has been characterized by decades of research which has attempted to elucidate the epidemiology of this complex relationship and to reduce carriage within poultry. While much work has focused on the mechanisms facilitating its success in contaminating chicken flocks (and other animal hosts), it remains difficult to consistently exclude Campylobacter under field conditions. Within the United Kingdom poultry industry, various bird genotypes with widely varying growth rates are available to meet market needs and consumer preferences. However, little is known about whether any differences in Campylobacter carriage exist across this modern broiler range. The aim of this study was to establish if a relationship exists between growth rate or breed and cecal Campylobacter concentration after natural commercial flock Campylobacter challenge. In one investigation, four pure line genotypes of various growth rates were grown together, while in the second, eight different commercial broiler genotypes were grown individually. In both studies, the Campylobacter concentration was measured in the ceca at 42 days of age, revealing no significant difference in cecal load between birds of different genotypes both in mixed- and single-genotype pens. This is important from a public health perspective and suggests that other underlying reasons beyond genotype are likely to control and affect Campylobacter colonization within chickens. Further studies to gain a better understanding of colonization dynamics and subsequent proliferation are needed, as are novel approaches to reduce the burden in poultry.

  14. Questioning the activity of active matter: the case of bird flocks

    NASA Astrophysics Data System (ADS)

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

    Animal flocking is a natural instance of active matter. What makes flocks active is the rearrangement of neighborhoods, which constantly remodels the network of interactions between individuals in the group, keeping the system out of equilibrium. Despite the predicted importance of this reshuffling, its true impact for natural flocks is not well understood. Here we analyse films of flocks of startlings with a novel statistical inference technique based on dynamical maximum entropy to measure the parameters of flock alignment - alignment strength, interaction range, and noise. We show that birds align their flight orientations must faster than they change neighbors. In the statistical mechanics sense, this means that flocks remain adiabatically in equilibrium, allowing for a rigorous analogy with equilibrium systems of interacting spins, and we show that an inference method based on equilibrium assumptions gives fully consistent results.

  15. Linear response to leadership, effective temperature, and decision making in flocks

    NASA Astrophysics Data System (ADS)

    Pearce, Daniel J. G.; Giomi, Luca

    2016-08-01

    Large collections of autonomously moving agents, such as animals or micro-organisms, are able to flock coherently in space even in the absence of a central control mechanism. While the direction of the flock resulting from this critical behavior is random, this can be controlled by a small subset of informed individuals acting as leaders of the group. In this article we use the Vicsek model to investigate how flocks respond to leadership and make decisions. Using a combination of numerical simulations and continuous modeling we demonstrate that flocks display a linear response to leadership that can be cast in the framework of the fluctuation-dissipation theorem, identifying an effective temperature reflecting how promptly the flock reacts to the initiative of the leaders. The linear response to leadership also holds in the presence of two groups of informed individuals with competing interests, indicating that the flock's behavioral decision is determined by both the number of leaders and their degree of influence.

  16. EBIS charge breeder for radioactive ion beams at ATLAS.

    SciTech Connect

    Ostroumov, P.; Kondrashev, S.; Pardo, R.; Savard, G.; Vondrasek, R.; Alessi, J.; Beebe, E.; Pikin, A.

    2010-07-01

    The construction of the Californium Rare Isotope Breeder Upgrade (CARIBU) for the Argonne National Laboratory ATLAS facility is completed and its commissioning is being performed. In its full capacity, the CARIBU facility will use fission fragments from a 1 Curie (Ci) {sup 252}Cf source. The ions will be thermalized and collected into a low-energy ion beam by a helium gas catcher, mass analyzed by an isobar separator, and charge bred to higher charge states for acceleration in ATLAS. To reach energies E/A 10 MeV/u, one should inject ions with charge-to-mass ratio (q/A) {ge} 1/7 into the ATLAS linac. In the first stage, the existing Electron Cyclotron Resonance (ECR) ion source will be used as a charge breeder. The maximum intensity of radioactive ion beams at the output of the gas catcher will not exceed 10{sup 7} ions per second. A charge breeder based on an Electron Beam Ion Source (EBIS) has significant advantages over the ECR option for ion beam intensities up to about 10{sup 9} ions per second, providing 3-4 times higher efficiency and significantly better purity of highly charged radioactive ion beams for further acceleration. The proposed EBIS project for CARIBU will heavily utilize state-of-the-art EBIS technology recently developed at Brookhaven National Laboratory. This will allow us to reduce both the project cost and timescale, simultaneously insuring reliable technical realization of the cutting-edge technology. Several parameters of the CARIBU EBIS charge breeder (EBIS-CB) will be relaxed with respect to the BNL EBIS in favor of higher reliability and lower cost. Technical performance of the CARIBU charge breeder will not suffer from such a relaxation and will provide high efficiency for a whole range of radioactive ion beams. The goal of this paper is to present the initial design of the EBIS charge breeder for radioactive ion beams at ATLAS.

  17. EBIS charge breeder for radioactive ion beams at ATLAS

    NASA Astrophysics Data System (ADS)

    Ostroumov, P.; Kondrashev, S.; Pardo, R.; Savard, G.; Vondrasek, R.; Alessi, J.; Beebe, E.; Pikin, A.

    2010-07-01

    The construction of the Californium Rare Isotope Breeder Upgrade (CARIBU) for the Argonne National Laboratory ATLAS facility is completed and its commissioning is being performed. In its full capacity, the CARIBU facility will use fission fragments from a 1 Curie (Ci) 252Cf source. The ions will be thermalized and collected into a low-energy ion beam by a helium gas catcher, mass analyzed by an isobar separator, and charge bred to higher charge states for acceleration in ATLAS. To reach energies E/A 10 MeV/u, one should inject ions with charge-to-mass ratio (q/A) >= 1/7 into the ATLAS linac. In the first stage, the existing Electron Cyclotron Resonance (ECR) ion source will be used as a charge breeder. The maximum intensity of radioactive ion beams at the output of the gas catcher will not exceed 107 ions per second. A charge breeder based on an Electron Beam Ion Source (EBIS) has significant advantages over the ECR option for ion beam intensities up to about 109 ions per second, providing 3-4 times higher efficiency and significantly better purity of highly charged radioactive ion beams for further acceleration. The proposed EBIS project for CARIBU will heavily utilize state-of-the-art EBIS technology recently developed at Brookhaven National Laboratory. This will allow us to reduce both the project cost and timescale, simultaneously insuring reliable technical realization of the cutting-edge technology. Several parameters of the CARIBU EBIS charge breeder (EBIS-CB) will be relaxed with respect to the BNL EBIS in favor of higher reliability and lower cost. Technical performance of the CARIBU charge breeder will not suffer from such a relaxation and will provide high efficiency for a whole range of radioactive ion beams. The goal of this paper is to present the initial design of the EBIS charge breeder for radioactive ion beams at ATLAS.

  18. EBIS charge breeder for radioactive ion beams at ATLAS

    SciTech Connect

    Ostroumov, P.; Alessi, J.; Kondrashev, S.; Pardo, R.; Savard, G.; Vondrasek, R.; Beebe, E.; Pikin, A.

    2010-07-20

    The construction of the Californium Rare Isotope Breeder Upgrade (CARIBU) for the Argonne National Laboratory ATLAS facility is completed and its commissioning is being performed. In its full capacity, the CARIBU facility will use fission fragments from a 1 Curie (Ci) {sup 252}Cf source. The ions will be thermalized and collected into a low-energy ion beam by a helium gas catcher, mass analyzed by an isobar separator, and charge bred to higher charge states for acceleration in ATLAS. To reach energies E/A 10 MeV/u, one should inject ions with charge-to-mass ratio (q/A) {ge} 1/7 into the ATLAS linac. In the first stage, the existing Electron Cyclotron Resonance (ECR) ion source will be used as a charge breeder. The maximum intensity of radioactive ion beams at the output of the gas catcher will not exceed 10{sup 7} ions per second. A charge breeder based on an Electron Beam Ion Source (EBIS) has significant advantages over the ECR option for ion beam intensities up to about 10{sup 9} ions per second, providing 3-4 times higher efficiency and significantly better purity of highly charged radioactive ion beams for further acceleration. The proposed EBIS project for CARIBU will heavily utilize state-of-the-art EBIS technology recently developed at Brookhaven National Laboratory. This will allow us to reduce both the project cost and timescale, simultaneously insuring reliable technical realization of the cutting-edge technology. Several parameters of the CARIBU EBIS charge breeder (EBIS-CB) will be relaxed with respect to the BNL EBIS in favor of higher reliability and lower cost. Technical performance of the CARIBU charge breeder will not suffer from such a relaxation and will provide high efficiency for a whole range of radioactive ion beams. The goal of this paper is to present the initial design of the EBIS charge breeder for radioactive ion beams at ATLAS.

  19. Are Kirindy sifaka capital or income breeders? It depends.

    PubMed

    Lewis, R J; Kappeler, P M

    2005-11-01

    The capital and income breeding framework has only recently been used to explain variation in female reproductive strategies in primates. The application of this framework to primates and other mammals with long reproductive cycles has not been consistent. We evaluated data on Verreaux's sifaka (Propithecus verreauxi verreauxi) in the Kirindy Forest of western Madagascar to determine whether they are capital or income breeders. We found that Verreaux's sifaka can be classified as either capital or income breeders, depending on how these concepts are operationalized. These conflicting findings highlight why the capital/income framework is currently problematic and must be standardized if it is to be a useful framework for primatologists.

  20. A case-control study on scrapie in Norwegian sheep flocks.

    PubMed

    Hopp, P; Ulvund, M J; Jarp, J

    2001-10-11

    Scrapie first was detected in indigenous sheep in Norway in 1981, and from 1995 to 1997 an increase in the number of flocks with scrapie cases was recorded. These flocks were mainly in one geographical region. A study to identify risk factors for scrapie was conducted. The study had three frequency-matched controls selected for every case within the same Veterinary District. A questionnaire was submitted to 176 sheep flocks (42 had been scrapie flocks). The data obtained by the questionnaire were linked to data collected from governmental and industry registers. After imputing missing data using single random imputation, the statistical analysis was performed using multivariable conditional logistic regression. Purchase of female sheep from scrapie flocks, sharing of rams, or sharing of pastures between different flocks were the risk factors associated with the occurrence of scrapie. Of factors potentially sustaining and promoting the infection in the flock, number of winter-fed sheep, number of buildings for housing sheep, rams and ewes shared room during mating period and increase in the flock size were associated with scrapie. We interpret these findings to show that factors involving transfer of sheep between flocks or direct contact between sheep of different flocks are important for the spread of scrapie. Management factors are important for the development of scrapie. However, it was not possible to discriminate between the different management factors in this study at the flock level. Also, factors indicating awareness and interest of the farmer (as well as willingness to contact a veterinarian for diseased sheep) were related to the detection of scrapie in the flock.

  1. Simulation and design of an electron beam ion source charge breeder for the californium rare isotope breeder upgrade

    NASA Astrophysics Data System (ADS)

    Dickerson, Clayton; Mustapha, Brahim; Pikin, Alexander; Kondrashev, Sergey; Ostroumov, Peter; Levand, Anthony; Fischer, Rick

    2013-02-01

    An electron beam ion source (EBIS) will be constructed and used to charge breed ions from the californium rare isotope breeder upgrade (CARIBU) for postacceleration into the Argonne tandem linear accelerator system (ATLAS). Simulations of the EBIS charge breeder performance and the related ion transport systems are reported. Propagation of the electron beam through the EBIS was verified, and the anticipated incident power density within the electron collector was identified. The full normalized acceptance of the charge breeder with a 2 A electron beam, 0.024πmmmrad for nominal operating parameters, was determined by simulating ion injection into the EBIS. The optics of the ion transport lines were carefully optimized to achieve well-matched ion injection, to minimize emittance growth of the injected and extracted ion beams, and to enable adequate testing of the charge bred ions prior to installation in ATLAS.

  2. Vigilance and feeding behaviour in large feeding flocks of laughing gulls, Larus atricilla, on Delaware Bay

    NASA Astrophysics Data System (ADS)

    Burger, Joanna; Gochfeld, Michael

    1991-02-01

    Laughing gulls ( Larus atricilla) forage on horseshoe crab ( Limulus polyphemus) eggs during May in Delaware Bay each year. They feed in dense flocks, and foraging rates vary with vigilance, bird density, number of steps and location in the flock, whereas time devoted to vigilance is explained by number of steps, density, location and feeding rates. The time devoted to vigilance decreases with increasing density, increasing foraging rates and decreasing aggression. Birds foraging on the edge of flocks take fewer pecks and more steps, and devote more time to vigilance than those in the intermediate or central parts of a flock.

  3. Nuclear breeder reactor fuel element with silicon carbide getter

    DOEpatents

    Christiansen, David W.; Karnesky, Richard A.

    1987-01-01

    An improved cesium getter 28 is provided in a breeder reactor fuel element or pin in the form of an extended surface area, low density element formed in one embodiment as a helically wound foil 30 located with silicon carbide, and located at the upper end of the fertile material upper blanket 20.

  4. Deployment Scenario of Heavy Water Cooled Thorium Breeder Reactor

    SciTech Connect

    Mardiansah, Deby; Takaki, Naoyuki

    2010-06-22

    Deployment scenario of heavy water cooled thorium breeder reactor has been studied. We have assumed to use plutonium and thorium oxide fuel in water cooled reactor to produce {sup 233}U which will be used in thorium breeder reactor. The objective is to analysis the potential of water cooled Th-Pu reactor for replacing all of current LWRs especially in Japan. In this paper, the standard Pressurize Water Reactor (PWR) has been designed to produce 3423 MWt; (i) Th-Pu PWR, (ii) Th-Pu HWR (MFR = 1.0) and (iii) Th-Pu HWR (MFR 1.2). The properties and performance of the core were investigated by using cell and core calculation code. Th-Pu PWR or HWR produces {sup 233}U to introduce thorium breeder reactor. The result showed that to replace all (60 GWe) LWR by thorium breeder reactor within a period of one century, Th-Pu oxide fueled PWR has insufficient capability to produce necessary amount of {sup 233}U and Th-Pu oxide fueled HWR has almost enough potential to produce {sup 233}U but shows positive void reactivity coefficient.

  5. Breeding nuclear fuels with accelerators — replacement for breeder reactors

    NASA Astrophysics Data System (ADS)

    Grand, P.; Takahashi, H.

    1985-05-01

    High-current, high-energy linear accelerators are potential competitors to breeder reactors and fusion devices for the production of fissile fuel. Accelerator breeder studies, conducted at Chalk River (Canada) and Brookhaven National Laboratory during the last decade, indicate that the technology is available and system's costs competitive with that of the LMFBR and Fusion-Hybrid systems. This paper addresses the technical issues to be faced in an accelerator specifically designed for commercial operation of this kind, the neutronics and engineering feasibility of target systems, and related fuel-cycle cost/benefit analysis. A nearly optimized accelerator breeder concept consisting of a 1.5 GeV, 300 mA linear accelerator, and of a H 2O-cooled, U-metal target (or thorium) has been designed and costed. Accelerator efficiency, beam-to-plug, is estimated at 50% and target power generation efficiency, beam-to-thermal output, at about 600% (U-metal case). Fuel costs produced by the facility are practically entirely driven by capital investment costs. This is also true for any competing system. On the basis, the accelerator breeder is economically competitive with the LMFBR while offering real advantages in terms of safety, fuel cycle flexibility, and resource independence.

  6. Evaluation of tritium release properties of advanced tritium breeders

    SciTech Connect

    Hoshino, T.; Ochiai, K.; Edao, Y.; Kawamura, Y.

    2015-03-15

    Demonstration power plant (DEMO) fusion reactors require advanced tritium breeders with high thermal stability. Lithium titanate (Li{sub 2}TiO{sub 3}) advanced tritium breeders with excess Li (Li{sub 2+x}TiO{sub 3+y}) are stable in a reducing atmosphere at high temperatures. Although the tritium release properties of tritium breeders are documented in databases for DEMO blanket design, no in situ examination under fusion neutron (DT neutron) irradiation has been performed. In this study, a preliminary examination of the tritium release properties of advanced tritium breeders was performed, and DT neutron irradiation experiments were performed at the fusion neutronics source (FNS) facility in JAEA. Considering the tritium release characteristics, the optimum grain size after sintering is <5 μm. From the results of the optimization of granulation conditions, prototype Li{sub 2+x}TiO{sub 3+y} pebbles with optimum grain size (<5 μm) were successfully fabricated. The Li{sub 2+x}TiO{sub 3+y} pebbles exhibited good tritium release properties similar to the Li{sub 2}TiO{sub 3} pebbles. In particular, the released amount of HT gas for easier tritium handling was higher than that of HTO water. (authors)

  7. Fission-suppressed hybrid reactor: the fusion breeder

    SciTech Connect

    Moir, R.W.; Lee, J.D.; Coops, M.S.

    1982-12-01

    Results of a conceptual design study of a /sup 233/U-producing fusion breeder are presented. The majority of the study was devoted to conceptual design and evaluation of a fission-suppressed blanket and to fuel cycle issues such as fuel reprocessing, fuel handling, and fuel management. Studies in the areas of fusion engineering, reactor safety, and economics were also performed.

  8. Water-cooled solid-breeder concept for ITER

    SciTech Connect

    Gohar, Y.; Baker, C.C.; Attaya, H.; Billone, M.; Clemmer, R.C.; Finn, P.A.; Hassanein, A.; Johnson, C.E.; Majumdar, S.; Mattas, R.F.

    1988-08-01

    A water-cooled solid-breeder blanket concept was developed for ITER. The main function of this blanket is to produce the necessary tritium for the ITER operation. Several design features are incorporated in this blanket concept to increase its attractiveness. It is assumed that the blanket operation at commercial power reactor conditions can be sacrificed to achieve a high tritium breeding ratio with minimum additional research and development, and minimal impact on reactor design and operation. Operating temperature limits are enforced for each material to insure a satisfactory blanket performance. In fact, the design was iterated to maximize the tritium breeding ratio and satisfy these temperature limits. The other design constraint is to permit a large increase in the neutron wall loading without exceeding the temperature limits for the different blanket materials. The blanket concept contains 1.8 cm of Li/sub 2/O and 22.5 cm of beryllium both with a 0.8 density factor. The water coolant is isolated from the breeder material by several zones which reduces the tritium buildup in the water by permeation, reduces the chance for water-breeder interaction, and permits the breeder to operate at high temperature with a low temperature coolant. This improves the safety and environmental aspects of the blanket and eliminates the costly process of the tritium recovery from the water. The key features and design analysis of this blanket are summarized in this paper. 11 refs., 2 figs., 3 tabs.

  9. Validation of the nylon flocked swab for planetary protection applications

    NASA Astrophysics Data System (ADS)

    Moissl-Eichinger, Christine; Probst, Alexander

    The major issue of planetary protection is to prevent the contamination of extraterrestrial en-vironments by terrestrial biomolecules and life forms. In order not to affect or even to confound future life detection missions on celestial bodies, which are of interest for their chemical and bi-ological evolution, spacecraft are constructed in clean rooms and are subject to severe cleaning processes and microbiological controls before launch. Microbiological assays are used to mea-sure and control the bioburden on spacecraft itself and spacecraft hardware during assembly. The current NASA standard assays have originally been developed for the Viking programme in the 70s. Due to the stringent contamination control constrains of the upcoming ESA Ex-oMars mission, these protocols cannot be used, in particular the application of cotton swabs with wooden applicators is no longer possible. Therefore, cotton swabs will be replaced by the novel nylon flocked swabs. In the study presented here, the nylon flocked swabs were validated for the usage for measuring and controling of the bioburden on spacecraft related surfaces. The absolute recovery efficiency was determined, following the guidelines of USP1223 in preci-sion, accuracy, robustness, specificity, linearity and limit of detection. As a standard surface, stainless steel coupons were used, whereas B. atrophaeus (spores) served as standard microbial strain. Additionally, the nylon flocked swab was used for experiments on different rough and smooth surfaces with seven different Bacillus spores and two different protocols. Further details will be given concerning the new ESA standard swab procedure for the microbial examination of flight hardware and clean rooms to be used for the upcoming ExoMars mission.

  10. Collective motion with anticipation: Flocking, spinning, and swarming

    NASA Astrophysics Data System (ADS)

    Morin, Alexandre; Caussin, Jean-Baptiste; Eloy, Christophe; Bartolo, Denis

    2015-01-01

    We investigate the collective dynamics of self-propelled particles able to probe and anticipate the orientation of their neighbors. We show that a simple anticipation strategy hinders the emergence of homogeneous flocking patterns. Yet anticipation promotes two other forms of self-organization: collective spinning and swarming. In the spinning phase, all particles follow synchronous circular orbits, while in the swarming phase, the population condensates into a single compact swarm that cruises coherently without requiring any cohesive interactions. We quantitatively characterize and rationalize these phases of polar active matter and discuss potential applications to the design of swarming robots.

  11. The effectiveness of mass vaccination on Marek's disease virus (MDV) outbreaks and detection within a broiler barn: A modeling study☆

    PubMed Central

    Atkins, Katherine E.; Read, Andrew F.; Walkden-Brown, Stephen W.; Savill, Nicholas J.; Woolhouse, Mark E.J.

    2013-01-01

    Marek's disease virus (MDV), a poultry pathogen, has been increasing in virulence since the mid twentieth century. Since multiple vaccines have been developed and widely implemented, losses due to MDV have decreased. However, vaccine failure has occurred in the past and vaccine breakthroughs remain a problem. Failure of disease control with current vaccines would have significant economic and welfare consequences. Nevertheless, the epidemiology of the disease during a farm outbreak is not well understood. Here we present a mathematical model to predict the effectiveness of vaccines to reduce the outbreak probability and disease burden within a barn. We find that the chance of an outbreak within a barn increases with the virulence of an MDV strain, and is significantly reduced when the flock is vaccinated, especially when there the contaminant strain is of low virulence. With low quantities of contaminated dust, there is nearly a 100% effectiveness of vaccines to reduce MDV outbreaks. However, the vaccine effectiveness drops to zero with an increased amount of contamination with a middle virulence MDV strain. We predict that the larger the barn, and the more virulent the MDV strain is, the more virus is produced by the time the flock is slaughtered. With the low-to-moderate virulence of the strains studied here, the number of deaths due to MDV is very low compared to all-cause mortality regardless of the vaccination status of the birds. However, the cumulative MD incidence can reach 100% for unvaccinated cohorts, and 35% for vaccinated cohorts. These results suggest that death due to MDV is an insufficient metric to assess the prevalence of MDV broiler barns regardless of vaccine status, such that active surveillance is required to successfully assess the probability of MDV outbreaks, and to limit transmission of MDV between successive cohorts of broiler chickens. PMID:24267877

  12. The effectiveness of mass vaccination on Marek's disease virus (MDV) outbreaks and detection within a broiler barn: a modeling study.

    PubMed

    Atkins, Katherine E; Read, Andrew F; Walkden-Brown, Stephen W; Savill, Nicholas J; Woolhouse, Mark E J

    2013-12-01

    Marek's disease virus (MDV), a poultry pathogen, has been increasing in virulence since the mid twentieth century. Since multiple vaccines have been developed and widely implemented, losses due to MDV have decreased. However, vaccine failure has occurred in the past and vaccine breakthroughs remain a problem. Failure of disease control with current vaccines would have significant economic and welfare consequences. Nevertheless, the epidemiology of the disease during a farm outbreak is not well understood. Here we present a mathematical model to predict the effectiveness of vaccines to reduce the outbreak probability and disease burden within a barn. We find that the chance of an outbreak within a barn increases with the virulence of an MDV strain, and is significantly reduced when the flock is vaccinated, especially when there the contaminant strain is of low virulence. With low quantities of contaminated dust, there is nearly a 100% effectiveness of vaccines to reduce MDV outbreaks. However, the vaccine effectiveness drops to zero with an increased amount of contamination with a middle virulence MDV strain. We predict that the larger the barn, and the more virulent the MDV strain is, the more virus is produced by the time the flock is slaughtered. With the low-to-moderate virulence of the strains studied here, the number of deaths due to MDV is very low compared to all-cause mortality regardless of the vaccination status of the birds. However, the cumulative MD incidence can reach 100% for unvaccinated cohorts, and 35% for vaccinated cohorts. These results suggest that death due to MDV is an insufficient metric to assess the prevalence of MDV broiler barns regardless of vaccine status, such that active surveillance is required to successfully assess the probability of MDV outbreaks, and to limit transmission of MDV between successive cohorts of broiler chickens.

  13. DIETARY AMINO ACID RESPONSES OF BROILER CHICKENS: A REVIEW

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In commercial practice, formulating diets to adequate amino acid (AA) minimums is critical to optimize live production and meat yield of broiler chickens. The modern broiler has lower feed intake per unit BW gain while having the potential to accrete more white meat than the commercial broiler of p...

  14. Campylobacter MLST Subtypes and Antimicrobial Susceptibility of Broiler Cecal Isolates: A Two Year Study from 142 Commercial Flocks

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Introduction: Campylobacter spp. are recognized as important agents of human foodborne gastroenteritis. To monitor trends in food safety and public health, antimicrobial susceptibility testing of Campylobacter derived from poultry products and infected patients has become common practice in both r...

  15. Canonical Discrimination of the Effect of a New Broiler Production Facility on Soil Chemical Profiles as Related to Current Management Practices

    PubMed Central

    Sheffield, Cynthia L.; Crippen, Tawni L.; Byrd, J. Allen; Beier, Ross C.; Yeater, Kathleen

    2015-01-01

    The effect dirt-floored broiler houses have on the underlying native soil, and the potential for contamination of the ground water by leaching under the foundation, is an understudied area. This study examines alterations in fifteen quantitative soil parameters (Ca, Cu, electrical conductivity, Fe, K, Mg, Mn, Na, NO3, organic matter, P, pH, S, soil moisture and Zn) in the underlayment of a newly constructed dirt-floored broiler house over the first two years of production (Native through Flock 11). The experiment was conducted near NW Robertson County, Texas, where the native soil is a fine, smectitic thermic Udertic Paleustalfs and the slopes range from zero to three percent. Multiple samples were collected from under each of three water and three feed lines the length of the house, in a longitudinal study during February 2008 through August 2010. To better define the relationship between the soil parameters and sampling times, a canonical discriminant analysis approach was used. The soil profiles assembled into five distinctive clusters corresponding to time and management practices. Results of this work revealed that the majority of parameters increased over time. The management practices of partial and total house clean-outs markedly altered soil profiles the house underlayment, thus reducing the risk of infiltration into the ground water near the farm. This is important as most broiler farms consist of several houses within a small area, so the cumulative ecological impact could be substantial if not properly managed. PMID:26029909

  16. Canonical discrimination of the effect of a new broiler production facility on soil chemical profiles as related to current management practices.

    PubMed

    Sheffield, Cynthia L; Crippen, Tawni L; Byrd, J Allen; Beier, Ross C; Yeater, Kathleen

    2015-01-01

    The effect dirt-floored broiler houses have on the underlying native soil, and the potential for contamination of the ground water by leaching under the foundation, is an understudied area. This study examines alterations in fifteen quantitative soil parameters (Ca, Cu, electrical conductivity, Fe, K, Mg, Mn, Na, NO3, organic matter, P, pH, S, soil moisture and Zn) in the underlayment of a newly constructed dirt-floored broiler house over the first two years of production (Native through Flock 11). The experiment was conducted near NW Robertson County, Texas, where the native soil is a fine, smectitic thermic Udertic Paleustalfs and the slopes range from zero to three percent. Multiple samples were collected from under each of three water and three feed lines the length of the house, in a longitudinal study during February 2008 through August 2010. To better define the relationship between the soil parameters and sampling times, a canonical discriminant analysis approach was used. The soil profiles assembled into five distinctive clusters corresponding to time and management practices. Results of this work revealed that the majority of parameters increased over time. The management practices of partial and total house clean-outs markedly altered soil profiles the house underlayment, thus reducing the risk of infiltration into the ground water near the farm. This is important as most broiler farms consist of several houses within a small area, so the cumulative ecological impact could be substantial if not properly managed.

  17. Behaviour of domestic ducks exposed to mobile predator stimuli. 1. Flock responses.

    PubMed

    Henderson, J V; Nicol, C J; Lines, J A; White, R P; Wathes, C M

    2001-09-01

    1. Small flocks of ducks (Anasplatyrhynchos domesticus) were exposed to two stimuli, a small mobile vehicle and a walking human, to investigate their flight responses. 2. Experiment 1. Flocks were herded around an annular arena by each stimulus at 0.5 ms(-1) and the flight distance between the stimulus and the centre of the flock, and individual positions within the flock were recorded every 10 s. Flocks maintained a significantly longer distance from the human (6.0 m) than the vehicle (5.1 m) and usually did not maintain visual contact with either stimulus. Significant consistency in individual positions within the flock was found within and between trials. 3. Experiment 2. Flocks were exposed to each stimulus which approached them as they were feeding in a circular arena. The latencies for cessation and resumption of feeding were recorded and the paths followed by the flocks described. Ducks showed a significantly shorter latency to cease feeding in response to the human (4.9 s) compared with the vehicle (6.9 s). 4. Domestic ducks apparently perceive an approaching human as a greater threat than a small vehicle. The findings are discussed in relation to the development of herding robots.

  18. Who Is Spreading Avian Influenza in the Moving Duck Flock Farming Network of Indonesia?

    PubMed

    Henning, Joerg; Pfeiffer, Dirk U; Stevenson, Mark; Yulianto, Didik; Priyono, Walujo; Meers, Joanne

    2016-01-01

    Duck populations are considered to be a reservoir of Highly pathogenic avian influenza (HPAI) virus H5N1 in some agricultural production systems, as they are able to shed the virus for several days without clinical signs. Countries endemically affected with HPAI in Asia are characterised by production systems where ducks are fed on post-harvest spilled rice. During this scavenging process it is common for ducks to come into contact with other duck flocks or wild birds, thereby providing opportunities for virus spread. Effective risk management for HPAI has been significantly compromised by a limited understanding of management of moving duck flocks in these countries, despite of a small number of recent investigations. Here, for the first time, we described the management of moving duck flocks and the structure of the moving duck flock network in quantitative terms so that factors influencing the risk of HPAIV transmission can be identified. By following moving duck flock farmers over a period of 6 months in Java, Indonesia, we were able to describe the movement of flocks and to characterise the network of various types of actors associated with the production system. We used these data to estimate the basic reproductive number for HPAI virus spread. Our results suggest that focussing HPAI prevention measures on duck flocks alone will not be sufficient. Instead, the role of transporters of moving duck flocks, hatcheries and rice paddy owners, in the spread of the HPAI virus needs to be recognised.

  19. Who Is Spreading Avian Influenza in the Moving Duck Flock Farming Network of Indonesia?

    PubMed

    Henning, Joerg; Pfeiffer, Dirk U; Stevenson, Mark; Yulianto, Didik; Priyono, Walujo; Meers, Joanne

    2016-01-01

    Duck populations are considered to be a reservoir of Highly pathogenic avian influenza (HPAI) virus H5N1 in some agricultural production systems, as they are able to shed the virus for several days without clinical signs. Countries endemically affected with HPAI in Asia are characterised by production systems where ducks are fed on post-harvest spilled rice. During this scavenging process it is common for ducks to come into contact with other duck flocks or wild birds, thereby providing opportunities for virus spread. Effective risk management for HPAI has been significantly compromised by a limited understanding of management of moving duck flocks in these countries, despite of a small number of recent investigations. Here, for the first time, we described the management of moving duck flocks and the structure of the moving duck flock network in quantitative terms so that factors influencing the risk of HPAIV transmission can be identified. By following moving duck flock farmers over a period of 6 months in Java, Indonesia, we were able to describe the movement of flocks and to characterise the network of various types of actors associated with the production system. We used these data to estimate the basic reproductive number for HPAI virus spread. Our results suggest that focussing HPAI prevention measures on duck flocks alone will not be sufficient. Instead, the role of transporters of moving duck flocks, hatcheries and rice paddy owners, in the spread of the HPAI virus needs to be recognised. PMID:27019344

  20. 9 CFR 145.53 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... Register citations affecting § 145.53, see the List of CFR Sections Affected, which appears in the Finding... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING... Breeding Flocks and Products § 145.53 Terminology and classification; flocks and products....

  1. 9 CFR 145.83 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Primary Meat-Type Chicken Breeding Flocks and Products § 145.83 Terminology... officially blood tested with no reactors. (2) It is a primary breeding flock that meets the...

  2. 9 CFR 145.73 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Primary Egg-Type Chicken Breeding Flocks and Products § 145.73 Terminology... officially blood tested with no reactors. (2) It is a primary breeding flock that meets the...

  3. 9 CFR 145.83 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Primary Meat-Type Chicken Breeding Flocks and Products § 145.83 Terminology... officially blood tested with no reactors. (2) It is a primary breeding flock that meets the...

  4. 9 CFR 145.83 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Primary Meat-Type Chicken Breeding Flocks and Products § 145.83 Terminology... officially blood tested with no reactors. (2) It is a primary breeding flock that meets the...

  5. 9 CFR 145.63 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Ostrich, Emu, Rhea, and Cassowary Breeding Flocks and Products § 145.63... tested within the past 12 months with no reactors. (2) It is a breeding flock that meets one of...

  6. 9 CFR 145.63 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Ostrich, Emu, Rhea, and Cassowary Breeding Flocks and Products § 145.63... tested within the past 12 months with no reactors. (2) It is a breeding flock that meets one of...

  7. 9 CFR 145.73 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Primary Egg-Type Chicken Breeding Flocks and Products § 145.73 Terminology... officially blood tested with no reactors. (2) It is a primary breeding flock that meets the...

  8. 9 CFR 145.73 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Primary Egg-Type Chicken Breeding Flocks and Products § 145.73 Terminology... officially blood tested with no reactors. (2) It is a primary breeding flock that meets the...

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

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Ostrich, Emu, Rhea, and Cassowary Breeding Flocks and Products § 145.63... tested within the past 12 months with no reactors. (2) It is a breeding flock that meets one of...

  10. 9 CFR 145.63 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Ostrich, Emu, Rhea, and Cassowary Breeding Flocks and Products § 145.63... tested within the past 12 months with no reactors. (2) It is a breeding flock that meets one of...

  11. 9 CFR 145.63 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Ostrich, Emu, Rhea, and Cassowary Breeding Flocks and Products § 145.63... tested within the past 12 months with no reactors. (2) It is a breeding flock that meets one of...

  12. 9 CFR 145.73 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Primary Egg-Type Chicken Breeding Flocks and Products § 145.73 Terminology... officially blood tested with no reactors. (2) It is a primary breeding flock that meets the...

  13. 9 CFR 145.53 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... Register citations affecting § 145.53, see the List of CFR Sections Affected, which appears in the Finding... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING... Breeding Flocks and Products § 145.53 Terminology and classification; flocks and products....

  14. 9 CFR 145.83 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Primary Meat-Type Chicken Breeding Flocks and Products § 145.83 Terminology... officially blood tested with no reactors. (2) It is a primary breeding flock that meets the...

  15. 9 CFR 145.73 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Primary Egg-Type Chicken Breeding Flocks and Products § 145.73 Terminology... officially blood tested with no reactors. (2) It is a primary breeding flock that meets the...

  16. 9 CFR 145.83 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING POULTRY Special Provisions for Primary Meat-Type Chicken Breeding Flocks and Products § 145.83 Terminology... officially blood tested with no reactors. (2) It is a primary breeding flock that meets the...

  17. 9 CFR 145.53 - Terminology and classification; flocks and products.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... Register citations affecting § 145.53, see the List of CFR Sections Affected, which appears in the Finding... SERVICE, DEPARTMENT OF AGRICULTURE LIVESTOCK IMPROVEMENT NATIONAL POULTRY IMPROVEMENT PLAN FOR BREEDING... Breeding Flocks and Products § 145.53 Terminology and classification; flocks and products....

  18. Preliminary investigation of bird and human movements and disease-management practices in noncommercial poultry flocks in southwestern British Columbia.

    PubMed

    Burns, Theresa E; Kelton, David; Ribble, Carl; Stephen, Craig

    2011-09-01

    Understanding normal movement patterns and husbandry practices of poultry production systems is important for understanding the dynamics of disease spread, and for controlling outbreaks of highly infectious diseases, such as highly pathogenic avian influenza. To learn about these patterns in the noncommercial or "backyard" poultry-keeping sector, an open-ended questionnaire was administered to 18 backyard-flock owners in British Columbia, Canada, and responses were analyzed descriptively. Six participants reported that they visited premises that were part of the commercial poultry system in the last year; however, bird movements between commercial and noncommercial farms were always unidirectional, from commercial to backyard. Bird movements into and out of participants' flocks occurred multiple times per month (two flocks), three times per year (five flocks), once or twice a year (nine flocks) and every 3-5 yr (two flocks). Visitors had direct contact with three participants' flocks multiple times per week; for other flocks, visitors had direct contact three times or less per year. Fourteen participants rarely had direct contact with other backyard flocks, three had contact more than once per week, and one had contact every 3 mo. Participants stated that the health of their birds was excellent (7), very good (3), good (6), O.K. (1), and all right (1), and used a median of two biosecurity practices to maintain health in their flock. Our findings suggest that bird movements are not likely to transmit disease from backyard to commercial flocks; however, human movements between backyard and commercial premises could transmit diseases. Within the backyard-flock sector, the majority of small flocks appear to pose little risk of disease transmission because they are maintained in semi-isolation from other flocks; however, a minority of flocks has high contact levels with other flocks and could be important in disease spread.

  19. Information transfer and behavioural inertia in starling flocks

    NASA Astrophysics Data System (ADS)

    Attanasi, Alessandro; Cavagna, Andrea; Del Castello, Lorenzo; Giardina, Irene; Grigera, Tomas S.; Jelić, Asja; Melillo, Stefania; Parisi, Leonardo; Pohl, Oliver; Shen, Edward; Viale, Massimiliano

    2014-09-01

    Collective decision-making in biological systems requires all individuals in the group to go through a behavioural change of state. During this transition fast and robust transfer of information is essential to prevent cohesion loss. The mechanism by which natural groups achieve such robustness, however, is not clear. Here we present an experimental study of starling flocks performing collective turns. We find that information about direction changes propagates across the flock with a linear dispersion law and negligible attenuation, hence minimizing group decoherence. These results contrast starkly with present models of collective motion, which predict diffusive transport of information. Building on spontaneous symmetry breaking and conservation-law arguments, we formulate a theory that correctly reproduces linear and undamped propagation. Essential to this framework is the inclusion of the birds' behavioural inertia. The theory not only explains the data, but also predicts that information transfer must be faster the stronger the group's orientational order, a prediction accurately verified by the data. Our results suggest that swift decision-making may be the adaptive drive for the strong behavioural polarization observed in many living groups.

  20. Assortative flocking in crossbills and implications for ecological speciation.

    PubMed

    Smith, Julie W; Sjoberg, Stephanie M; Mueller, Matthew C; Benkman, Craig W

    2012-10-22

    How reproductive isolation is related to divergent natural selection is a central question in speciation. Here, we focus on several ecologically specialized taxa or 'call types' of red crossbills (Loxia curvirostra complex), one of the few groups of birds providing much evidence for ecological speciation. Call types differ in bill sizes and feeding capabilities, and also differ in vocalizations, such that contact calls provide information on crossbill phenotype. We found that two call types of red crossbills were more likely to approach playbacks of their own call type than those of heterotypics, and that their propensity to approach heterotypics decreased with increasing divergence in bill size. Although call similarity also decreased with increasing divergence in bill size, comparisons of responses to familiar versus unfamiliar call types indicate that the decrease in the propensity to approach heterotypics with increasing divergence in bill size was a learned response, and not a by-product of calls diverging pleiotropically as bill size diverged. Because crossbills choose mates while in flocks, assortative flocking could lead indirectly to assortative mating as a by-product. These patterns of association therefore provide a mechanism by which increasing divergent selection can lead to increasing reproductive isolation. PMID:22915674

  1. The seroprevalence of Toxoplasma gondii in Ontario sheep flocks

    PubMed Central

    Waltner-Toews, David; Mondesire, Roy; Menzies, Paula

    1991-01-01

    In a random sample of 103 sheep farms in Ontario, 99% of the farms had some sheep serologically positive for Toxoplasma gondii, based on an enzymelinked immunosorbent assay (ELISA). The percent of sheep affected within farms ranged from 3.8% to 97.8%, with an average flock prevalence of 57.6%. When farm management variables were considered in a multivariate analysis, significantly lower rates of serologically positive sheep were associated with neutering of female cats and clipping of ewes' perineums before lambing; significantly higher prevalence rates were found on farms where sheep were purchased from other flocks, pigs were raised on the same farm, sheep shared pasture with other animals, flowing water was available at pasture, and pastured replacements had access to housing. As well, in univariate analyses, higher prevalence was positively associated with an increasing number of cat litters born over the previous two years and offering creep feed or forage to lambs, and inversely with the amount of labor expended on sheep rearing. PMID:17423914

  2. Information transfer and behavioural inertia in starling flocks.

    PubMed

    Attanasi, Alessandro; Cavagna, Andrea; Del Castello, Lorenzo; Giardina, Irene; Grigera, Tomas S; Jelić, Asja; Melillo, Stefania; Parisi, Leonardo; Pohl, Oliver; Shen, Edward; Viale, Massimiliano

    2014-09-01

    Collective decision-making in biological systems requires all individuals in the group to go through a behavioural change of state. During this transition fast and robust transfer of information is essential to prevent cohesion loss. The mechanism by which natural groups achieve such robustness, though, is not clear. Here we present an experimental study of starling flocks performing collective turns. We find that information about direction changes propagates across the flock with a linear dispersion law and negligible attenuation, hence minimizing group decoherence. These results contrast starkly with current models of collective motion, which predict diffusive transport of information. Building on spontaneous symmetry breaking and conservation laws arguments, we formulate a new theory that correctly reproduces linear and undamped propagation. Essential to the new framework is the inclusion of the birds' behavioural inertia. The new theory not only explains the data, but also predicts that information transfer must be faster the stronger the group's orientational order, a prediction accurately verified by the data. Our results suggest that swift decision-making may be the adaptive drive for the strong behavioural polarization observed in many living groups. PMID:25264452

  3. Mic Flocks in the Cloud: Harnessing Mobile Ubiquitous Sensor Networks

    NASA Astrophysics Data System (ADS)

    Garces, M. A.; Christe, A.

    2015-12-01

    Smartphones provide a commercial, off-the-shelf solution to capture, store, analyze, and distribute infrasound using on-board or external microphones (mics) as well as on-board barometers. Free iOS infrasound apps can be readily downloaded from the Apple App Store, and Android versions are in progress. Infrasound propagates for great distances, has low sample rates, and provides a tractable pilot study scenario for open distributed sensor networks at regional and global scales using one of the most ubiquitous sensors on Earth - microphones. Data collection is no longer limited to selected vendors at exclusive prices: anybody on Earth can record and stream infrasound, and the diversity of recording systems and environments is rapidly expanding. Global deployment may be fast and easy (www.redvox.io), but comes with the cost of increasing data volume, velocity, variety, and complexity. Flocking - the collective motion of mobile agents - is a natural human response to threats or events of interest. Anticipating, modeling and harnessing flocking sensor topologies will be necessary for adaptive array and network processing. The increasing data quantity and complexity will exceed the processing capacity of human analysts and most research servers. We anticipate practical real-time applications will require the on-demand adaptive scalability and resources of the Cloud. Cloud architectures for such heterogeneous sensor networks will consider eventual integration into the Global Earth Observation System of Systems (GEOSS).

  4. Diphacinone and zinc phosphide toxicity in a flock of Peafowl.

    PubMed

    Shivaprasad, H L; Galey, F

    2001-12-01

    Toxicity probably due to a combination of diphacinone and zinc phosphide was diagnosed in a flock of peafowl, in which 35 birds in a flock of 80 died over a span of 10 days without any apparent clinical signs. Chickens and guinea fowl, 30 each on the same premises, were not affected. Plastic tubes containing diphacinone and zinc phosphide were used on the premises to control ground squirrels. Most of the six dead peafowl, which ranged in age from 6 months to 4 years, had an accumulation of serosanguinous fluid in the abdominal cavity, semi-clotted blood over the liver lobes, increased pericardial fluid, and enlarged and pale kidneys. Pellets of diphacinone and zinc phosphide were found in the crop and gizzard contents from most of the birds. Microscopically, most of the birds had mild to moderate centrolobular degeneration of hepatocytes and multifocal degeneration of myofibres in the heart with infiltration by a few mononuclear cells. Acute nephrosis and mucosal oedema in the oesophagus and crop were also observed. Toxicological analysis of the crop and gizzard contents revealed the presence of diphacinone and phosphine gas, and analysis of the crop contents from two birds for heavy metals revealed zinc levels of up to 6600 parts/10 6 . It was suspected that only the peafowl and not the chickens and guinea fowl were affected because peafowl, with their longer necks, were able to reach into the plastic tubes and eat the pellets.

  5. A Distributed Flocking Approach for Information Stream Clustering Analysis

    SciTech Connect

    Cui, Xiaohui; Potok, Thomas E

    2006-01-01

    Intelligence analysts are currently overwhelmed with the amount of information streams generated everyday. There is a lack of comprehensive tool that can real-time analyze the information streams. Document clustering analysis plays an important role in improving the accuracy of information retrieval. However, most clustering technologies can only be applied for analyzing the static document collection because they normally require a large amount of computation resource and long time to get accurate result. It is very difficult to cluster a dynamic changed text information streams on an individual computer. Our early research has resulted in a dynamic reactive flock clustering algorithm which can continually refine the clustering result and quickly react to the change of document contents. This character makes the algorithm suitable for cluster analyzing dynamic changed document information, such as text information stream. Because of the decentralized character of this algorithm, a distributed approach is a very natural way to increase the clustering speed of the algorithm. In this paper, we present a distributed multi-agent flocking approach for the text information stream clustering and discuss the decentralized architectures and communication schemes for load balance and status information synchronization in this approach.

  6. Diphacinone and zinc phosphide toxicity in a flock of Peafowl.

    PubMed

    Shivaprasad, H L; Galey, F

    2001-12-01

    Toxicity probably due to a combination of diphacinone and zinc phosphide was diagnosed in a flock of peafowl, in which 35 birds in a flock of 80 died over a span of 10 days without any apparent clinical signs. Chickens and guinea fowl, 30 each on the same premises, were not affected. Plastic tubes containing diphacinone and zinc phosphide were used on the premises to control ground squirrels. Most of the six dead peafowl, which ranged in age from 6 months to 4 years, had an accumulation of serosanguinous fluid in the abdominal cavity, semi-clotted blood over the liver lobes, increased pericardial fluid, and enlarged and pale kidneys. Pellets of diphacinone and zinc phosphide were found in the crop and gizzard contents from most of the birds. Microscopically, most of the birds had mild to moderate centrolobular degeneration of hepatocytes and multifocal degeneration of myofibres in the heart with infiltration by a few mononuclear cells. Acute nephrosis and mucosal oedema in the oesophagus and crop were also observed. Toxicological analysis of the crop and gizzard contents revealed the presence of diphacinone and phosphine gas, and analysis of the crop contents from two birds for heavy metals revealed zinc levels of up to 6600 parts/10 6 . It was suspected that only the peafowl and not the chickens and guinea fowl were affected because peafowl, with their longer necks, were able to reach into the plastic tubes and eat the pellets. PMID:19184953

  7. Effects of Agent's Repulsion in 2d Flocking Models

    NASA Astrophysics Data System (ADS)

    Moussa, Najem; Tarras, Iliass; Mazroui, M'hammed; Boughaleb, Yahya

    In nature many animal groups, such as fish schools or bird flocks, clearly display structural order and appear to move as a single coherent entity. In order to understand the complex behavior of these systems, many models have been proposed and tested so far. This paper deals with an extension of the Vicsek model, by including a second zone of repulsion, where each agent attempts to maintain a minimum distance from the others. The consideration of this zone in our study seems to play an important role during the travel of agents in the two-dimensional (2D) flocking models. Our numerical investigations show that depending on the basic ingredients such as repulsion radius (R1), effect of density of agents (ρ) and noise (η), our nonequilibrium system can undergo a kinetic phase transition from no transport to finite net transport. For different values of ρ, kinetic phase diagrams in the plane (η ,R1) are found. Implications of these findings are discussed.

  8. 9 CFR 54.8 - Requirements for flock plans and post-exposure management and monitoring plans.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... determine, the following: sire, dam, and offspring of the animal; (3) Date of acquisition and previous flock... cause of death, if known, or date of removal from the flock and name and address of the person to whom... choose to maintain, the date and cause of death, if known, or date of removal from the flock and name...

  9. 9 CFR 54.8 - Requirements for flock plans and post-exposure management and monitoring plans.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... determine, the following: sire, dam, and offspring of the animal; (3) Date of acquisition and previous flock... cause of death, if known, or date of removal from the flock and name and address of the person to whom... choose to maintain, the date and cause of death, if known, or date of removal from the flock and name...

  10. 9 CFR 54.8 - Requirements for flock plans and post-exposure management and monitoring plans.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... determine, the following: sire, dam, and offspring of the animal; (3) Date of acquisition and previous flock... cause of death, if known, or date of removal from the flock and name and address of the person to whom... choose to maintain, the date and cause of death, if known, or date of removal from the flock and name...

  11. 9 CFR 54.8 - Requirements for flock plans and post-exposure management and monitoring plans.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... determine, the following: sire, dam, and offspring of the animal; (3) Date of acquisition and previous flock... cause of death, if known, or date of removal from the flock and name and address of the person to whom... choose to maintain, the date and cause of death, if known, or date of removal from the flock and name...

  12. 9 CFR 54.8 - Requirements for flock plans and post-exposure management and monitoring plans.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... determine, the following: sire, dam, and offspring of the animal; (3) Date of acquisition and previous flock... cause of death, if known, or date of removal from the flock and name and address of the person to whom... choose to maintain, the date and cause of death, if known, or date of removal from the flock and name...

  13. 9 CFR 147.10 - Laboratory procedure recommended for the bacteriological examination of egg-type breeding flocks...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... the bacteriological examination of egg-type breeding flocks with salmonella enteritidis positive... examination of egg-type breeding flocks with salmonella enteritidis positive environments. Birds selected for bacteriological examination from egg-type breeding flocks positive for Salmonella enteritidis after...

  14. Feather corticosterone evaluated by ELISA in broilers: a potential tool to evaluate broiler welfare.

    PubMed

    Carbajal, A; Tallo-Parra, O; Sabes-Alsina, M; Mular, I; Lopez-Bejar, M

    2014-11-01

    The measure of corticosterone (CORT) in feathers has been recently recognized as a valid and easily obtainable measure of chronic glucocorticoids secretion in avian species. This measure provides meaningful interpretations of how individuals respond to environmental perturbations. The growing interest of the public toward animal-food production welfare shows the need for improving and expanding objective tools to evaluate this issue. The present study evaluates whether it is possible to detect CORT in broiler feathers, and thus, assess if it would be a useful measure to study broiler welfare. Twenty-two broilers were randomly selected from an intensive farm. Four to 6 dorsal feathers were collected from each bird, and sex, weight, and morphological aspects of feather status were recorded. We tested the feasibility for detecting CORT in broiler feathers by ELISA, which had never been done before, and an assay validation test was performed. No significant relationships were found between feather CORT concentrations and physiological variables such as sex, weight, and fault bars in broilers. To our knowledge, this is the first study that uses broiler feathers as a matrix that provides a retrospective record of their hypothalamic-pituitary-adrenal activity. Results indicate that ELISA is a valid tool to detect feather CORT levels in broilers.

  15. Molecular detection of chicken parvovirus in broilers with enteric disorders presenting curving of duodenal loop, pancreatic atrophy, and mesenteritis.

    PubMed

    Nuñez, L F N; Sá, L R M; Parra, S H S; Astolfi-Ferreira, C S; Carranza, C; Ferreira, A J P

    2016-04-01

    Enteric disorders are an important cause of economic losses in broiler chickens worldwide. Several agents have been associated with enteric problems, such as viruses, bacteria, and parasites. In this study, broiler chickens showing signs of enteric disorders were subjected to molecular diagnosis for several viral agents and also for pathological examination for elucidating this problem. Thus, the chickens were screened for avian nephritis virus (ANV), chicken astrovirus (CAstV), avian rotavirus (ArtV), avian reovirus (AReoV), infectious bronchitis virus (IBV), fowl adenovirus group I (FAdV-1), and chicken parvovirus (ChPV). Postmortem examinations revealed a curving of the duodenal loop (J-like appearance) and intestines filled with liquid and gaseous content. Histopathological analysis of the duodenal loop showed pancreatic atrophy, acute mesenteritis, and enteritis. PCR results showed that ChPV was the sole viral agent detected in samples with lesions such as the curved duodenal loop and pancreatic atrophy. Molecular characterization of the nucleotide and deduced amino acid sequences revealed a high similarity with other strains of ChPV from Brazil, Canada, United States, Europe, and Asia. These findings suggest an association between ChPV and the development of enteritis, pancreatitis, and pancreatic atrophy, which may lead to curling of the duodenal loop. Together, these alterations may disrupt the normal functioning of the digestive system, diminishing digestion and the absorption of dietary nutrients and consequently leading to reduced weight gain, flock impairment, dwarfism, and an elevated feed conversion rate. PMID:26908891

  16. Molecular detection of chicken parvovirus in broilers with enteric disorders presenting curving of duodenal loop, pancreatic atrophy, and mesenteritis.

    PubMed

    Nuñez, L F N; Sá, L R M; Parra, S H S; Astolfi-Ferreira, C S; Carranza, C; Ferreira, A J P

    2016-04-01

    Enteric disorders are an important cause of economic losses in broiler chickens worldwide. Several agents have been associated with enteric problems, such as viruses, bacteria, and parasites. In this study, broiler chickens showing signs of enteric disorders were subjected to molecular diagnosis for several viral agents and also for pathological examination for elucidating this problem. Thus, the chickens were screened for avian nephritis virus (ANV), chicken astrovirus (CAstV), avian rotavirus (ArtV), avian reovirus (AReoV), infectious bronchitis virus (IBV), fowl adenovirus group I (FAdV-1), and chicken parvovirus (ChPV). Postmortem examinations revealed a curving of the duodenal loop (J-like appearance) and intestines filled with liquid and gaseous content. Histopathological analysis of the duodenal loop showed pancreatic atrophy, acute mesenteritis, and enteritis. PCR results showed that ChPV was the sole viral agent detected in samples with lesions such as the curved duodenal loop and pancreatic atrophy. Molecular characterization of the nucleotide and deduced amino acid sequences revealed a high similarity with other strains of ChPV from Brazil, Canada, United States, Europe, and Asia. These findings suggest an association between ChPV and the development of enteritis, pancreatitis, and pancreatic atrophy, which may lead to curling of the duodenal loop. Together, these alterations may disrupt the normal functioning of the digestive system, diminishing digestion and the absorption of dietary nutrients and consequently leading to reduced weight gain, flock impairment, dwarfism, and an elevated feed conversion rate.

  17. Country report: Broiler industry and broiler litter-related problems in the southeastern United States.

    PubMed

    Paudel, Krishna P; McIntosh, Christopher S

    2005-01-01

    This report describes the development of the broiler litter problem in the southeastern United States, including the economic opportunity and environmental challenges brought to the region by the industry. Through an analysis applied to the State of Georgia, land application of litter as a disposal alternative is examined along with its associated benefits. The analysis indicates that litter could be transported economically up to 256 km for cropland application. Excessive broiler litter production in a few concentrated regions is expected to stimulate the development of alternative approaches to broiler litter management, such as electricity generation.

  18. Fuel Summary Report: Shippingport Light Water Breeder Reactor - Rev. 2

    SciTech Connect

    Olson, Gail Lynn; Mc Cardell, Richard Keith; Illum, Douglas Brent

    2002-09-01

    The Shippingport Light Water Breeder Reactor (LWBR) was developed by Bettis Atomic Power Laboratory to demonstrate the potential of a water-cooled, thorium oxide fuel cycle breeder reactor. The LWBR core operated from 1977-82 without major incident. The fuel and fuel components suffered minimal damage during operation, and the reactor testing was deemed successful. Extensive destructive and nondestructive postirradiation examinations confirmed that the fuel was in good condition with minimal amounts of cladding deformities and fuel pellet cracks. Fuel was placed in wet storage upon arrival at the Expended Core Facility, then dried and sent to the Idaho Nuclear Technology and Engineering Center for underground dry storage. It is likely that the fuel remains in good condition at its current underground dry storage location at the Idaho Nuclear Technology and Engineering Center. Reports show no indication of damage to the core associated with shipping, loading, or storage.

  19. Role of the breeder in long-term energy economics

    SciTech Connect

    Kosobud, R.F.; Daly, T.A.; Chang, Y.I.

    1982-01-01

    Private and public decisions affecting the use of nuclear and other energy technologies over a long-run time horizon were studied using the ETA-MACRO model which provides for economic- and energy-sector interactions. The impact on the use of competing energy technologies of a public decision to apply benefit-cost analysis to the production of carbon dioxide that enters the atmosphere is considered. Assuming the public choice is to impose an appropriate penalty tax on those technologies which generate CO/sub 2/ and to allow decentralized private decisions to choose the optimal mix of energy technologies that maximize a nonlinear objective function subject to constraints, the study showed that breeder technology provides a much-larger share of domestically consumed energy. Having the breeder technology available as a substitute permits control of CO/sub 2/ without significant reductions in consumption or gross national product growth paths.

  20. ECRIS and EBIS charge state breeders: Present performances, future potentials

    NASA Astrophysics Data System (ADS)

    Delahaye, Pierre

    2013-12-01

    Facilities reaccelerating radioactive ion beams face diverse technical challenges, from the production of radioactive isotopes to their post-acceleration. First operational at REX-ISOLDE, the charge state breeding in source of highly charged ions has become a key technique for optimizing the capabilities and performances of a post-accelerator. Charge state breeding in Electron Beam Ion Sources or Traps (EBIS/T) or in Electron Cyclotron Resonance Ion Sources (ECRIS) are techniques competing to reach high efficiencies, high charge states, and rapid charge breeding times. Beam purity, efficiency for light ions and short lived isotopes, duty cycles and time structures are still major issues being addressed very differently according to the type of charge breeder. The present performances and limitations for each charge breeder, and directions of the R&D pursued for different major projects are being discussed.

  1. Charge breeder for the SPIRAL1 upgrade: Preliminary results

    NASA Astrophysics Data System (ADS)

    Maunoury, L.; Delahaye, P.; Dubois, M.; Angot, J.; Sole, P.; Bajeat, O.; Barton, C.; Frigot, R.; Jeanne, A.; Jardin, P.; Kamalou, O.; Lecomte, P.; Osmond, B.; Peschard, G.; Lamy, T.; Savalle, A.

    2016-02-01

    In the framework of the SPIRAL1 upgrade under progress at the GANIL lab, the charge breeder based on a LPSC Phoenix ECRIS, first tested at ISOLDE has been modified to benefit of the last enhancements of this device from the 1+/n+ community. The modifications mainly concern the 1 + optics, vacuum techniques, and the RF—buffer gas injection into the charge breeder. Prior to its installation in the midst of the low energy beam line of the SPIRAL1 facility, it has been decided to qualify its performances and several operation modes at the test bench of LPSC lab. This contribution shall present preliminary results of experiments conducted at LPSC concerning the 1 + to n+ conversion efficiencies for noble gases as well as for alkali elements and the corresponding transformation times.

  2. Charge breeder for the SPIRAL1 upgrade: Preliminary results.

    PubMed

    Maunoury, L; Delahaye, P; Dubois, M; Angot, J; Sole, P; Bajeat, O; Barton, C; Frigot, R; Jeanne, A; Jardin, P; Kamalou, O; Lecomte, P; Osmond, B; Peschard, G; Lamy, T; Savalle, A

    2016-02-01

    In the framework of the SPIRAL1 upgrade under progress at the GANIL lab, the charge breeder based on a LPSC Phoenix ECRIS, first tested at ISOLDE has been modified to benefit of the last enhancements of this device from the 1+/n+ community. The modifications mainly concern the 1 + optics, vacuum techniques, and the RF-buffer gas injection into the charge breeder. Prior to its installation in the midst of the low energy beam line of the SPIRAL1 facility, it has been decided to qualify its performances and several operation modes at the test bench of LPSC lab. This contribution shall present preliminary results of experiments conducted at LPSC concerning the 1 + to n+ conversion efficiencies for noble gases as well as for alkali elements and the corresponding transformation times. PMID:26932061

  3. Feasibility study on the thorium fueled boiling water breeder reactor

    SciTech Connect

    PetrusTakaki, N.

    2012-07-01

    The feasibility of (Th,U)O 2 fueled, boiling water breeder reactor based on conventional BWR technology has been studied. In order to determine the potential use of water cooled thorium reactor as a competitive breeder, this study evaluated criticality, breeding and void reactivity coefficient in response to changes made in MFR and fissile enrichments. The result of the study shows that while using light water as moderator, low moderator to fuel volume ratio (MFR=0.5), it was possible to breed fissile fuel in negative void reactivity condition. However the burnup value was lower than the value of the current LWR. On the other hand, heavy water cooled reactor shows relatively wider feasible breeding region, which lead into possibility of designing a core having better neutronic and economic performance than light water with negative void reactivity coefficient. (authors)

  4. Winter broiler litter gases and nitrogen compounds: Temporal and spatial trends

    NASA Astrophysics Data System (ADS)

    Miles, D. M.; Rowe, D. E.; Owens, P. R.

    Understanding how animal activities, management, and barn structure affect litter gases and nutrients is fundamental to developing accurate emission models for meat-bird facilities. This research characterized the temporal and spatial variability of litter ammonia (NH 3) and nitrous oxide (N 2O) flux via a chamber method, as well as determined litter nitrogen (N) compounds by intensive sampling in two commercial broiler houses on aged litter. Thirty-six grid samples were taken during a winter flock in Mississippi on days 2, 22, and 45. On day 45, eight additional samples were taken near the feeders and waterers (F/W). Geostatistical contour plots indicate NH 3 flux on day 2 was elevated in the brood area of house one (H1) where litter and air temperatures were highest; a commercial litter treatment held the NH 3 flux near zero for approximately 45% of the brood area in house two (H2). Day 45 NH 3 fluxes were similar, averaging 694 mg m -2 h -1 in H1 vs. 644 mg m -2 h -1 in H2; both houses exhibited greater NH 3 flux near the cooling pads. Ammonia flux, litter moisture and pH were diminished at the F/W locations. Heavy cake near the exhaust fans provided the lowest recorded litter pH, highest litter moisture and ammonium (NH 4) with no NH 3 flux at the flock's end. Trends in litter condition based on bird activity were evident, but individual differences persisted between the houses. The importance of cake formation over the litter surface and differences based on location, both related to bird activity and house structure, should be considered in NH 3 mitigation strategies.

  5. Evaluation of organic moderator/coolants for fusion breeder blankets

    SciTech Connect

    Romero, J.B.

    1980-03-01

    Organic coolants have several attractive features for fusion breeder blanket design. Their apparent compatibility with lithium and their ideal physical and nuclear properties allows straight-forward, high performance designs. Radiolytic damage can be reduced to about the same order as comparable fission systems by using multiplier/stripper blanket designs. Tritium recovery from the organic should be straightforward, but additional data is needed to make a better assessment of the economics of the process.

  6. Steam generator for liquid metal fast breeder reactor

    DOEpatents

    Gillett, James E.; Garner, Daniel C.; Wineman, Arthur L.; Robey, Robert M.

    1985-01-01

    Improvements in the design of internal components of J-shaped steam generators for liquid metal fast breeder reactors. Complex design improvements have been made to the internals of J-shaped steam generators which improvements are intended to reduce tube vibration, tube jamming, flow problems in the upper portion of the steam generator, manufacturing complexities in tube spacer attachments, thermal stripping potentials and difficulties in the weld fabrication of certain components.

  7. Solid breeder/structure mechanical interaction and thermal stability

    SciTech Connect

    Liu, Y.Y.; Billone, M.C.; Taghavi, K.

    1985-04-01

    Solid breeder/structure mechanical interaction (BSMI) during fusion reactor blanket operation is a potential failure mode which could limit the lifetime of the blanket. The severity of BSMI will generally depend on the materials, specific blanket designs, and blanket operating conditions. Thermomechanical analyses performed for a helium-cooled blanket employing Li/sub 2/O/HT-9 plates indicate that BSMI could be a serious concern for this blanket.

  8. Characterization of gaseous pollutant and particulate matter emission rates from a commercial broiler operation part II: Correlated emission rates

    NASA Astrophysics Data System (ADS)

    Roumeliotis, Taylor S.; Dixon, Brad J.; Van Heyst, Bill J.

    2010-10-01

    Emission rates of ammonia, acid gases, inorganic aerosols, methane, and size fractionated particulate matter were measured from a commercial broiler facility. This paper discusses the statistically influential parameters on numerous pollutants' emission from a broiler chicken facility and generates emission correlations to fill data gaps and develop averaged emission factors. Live mass of the birds was commonly a significant variable to each pollutant's emission. Some variables significantly impacted the pollutants' emissions, such as litter moisture content, but were measured discretely and cannot be used for filling in data gaps. House parameter correlations were, therefore, developed using parameters measured at the facility, such as indoor temperature, relative humidity, and the live mass of the birds, and relied on the mutual behaviour of discretely measured explanatory parameters and continuously monitored confounding variables. The live mass and the difference in the indoor temperature and the house set-point temperature were the most significant variables in each pollutant's correlation. The correlations predicted each pollutants emission to within 20% (total mass basis) over most broiler production cycles. Their validation on independent datasets also successfully estimated the flocks' emissions to within 3%. Emission factors (EFs) were developed for methane, ammonia, and size fractionated particulate matter using measured data and correlated emissions to fill in data gaps. PM 10 (particulate matter ≤10 microns) EFs were estimated to be 4.6 and 5.9 g d -1 [Animal Unit, AU] -1 for five and six week production cycles, respectively. PM 2.5 (PM ≤ 2.5 microns) EFs were 0.8 and 1.4 g d -1 AU -1 for five and six week cycles, respectively. Ammonia and methane emission factors were estimated at 120.8 and 197.0 g d -1 AU -1, respectively for a five week production cycle.

  9. Role of Mitochondrial Membrane Spherules in Flock House Virus Replication

    PubMed Central

    Short, James R.; Speir, Jeffrey A.; Gopal, Radhika; Pankratz, Logan M.; Lanman, Jason

    2016-01-01

    ABSTRACT Viruses that generate double-stranded RNA (dsRNA) during replication must overcome host defense systems designed to detect this infection intermediate. All positive-sense RNA viruses studied to date modify host membranes to help facilitate the sequestration of dsRNA from host defenses and concentrate replication factors to enhance RNA production. Flock House virus (FHV) is an attractive model for the study of these processes since it is well characterized and infects Drosophila cells, which are known to have a highly effective RNA silencing system. During infection, FHV modifies the outer membrane of host mitochondria to form numerous membrane invaginations, called spherules, that are ∼50 nm in diameter and known to be the site of viral RNA replication. While previous studies have outlined basic structural features of these invaginations, very little is known about the mechanism underlying their formation. Here we describe the optimization of an experimental system for the analysis of FHV host membrane modifications using crude mitochondrial preparations from infected Drosophila cells. These preparations can be programmed to synthesize both single- and double-stranded FHV RNA. The system was used to demonstrate that dsRNA is protected from nuclease digestion by virus-induced membrane invaginations and that spherules play an important role in stimulating RNA replication. Finally, we show that spherules generated during FHV infection appear to be dynamic as evidenced by their ability to form or disperse based on the presence or absence of RNA synthesis. IMPORTANCE It is well established that positive-sense RNA viruses induce significant membrane rearrangements in infected cells. However, the molecular mechanisms underlying these rearrangements, particularly membrane invagination and spherule formation, remain essentially unknown. How the formation of spherules enhances viral RNA synthesis is also not understood, although it is assumed to be partly a result

  10. Breeding nuclear fuels with accelerators: replacement for breeder reactors

    SciTech Connect

    Grand, P.; Takahashi, H.

    1984-01-01

    One application of high energy particle accelerators has been, and still is, the production of nuclear fuel for the nuclear energy industry; tantalizing because it would create a whole new industry. This approach to producing fissile from fertile material was first considered in the early 1950's in the context of the nuclear weapons program. A considerable development effort was expended before discovery of uranium ore in New Mexico put an end to the project. Later, US commitment to the Liquid Metal Fast Breeder Reactors (LMFBR) killed any further interest in pursuing accelerator breeder technology. Interest in the application of accelerators to breed nuclear fuels, and possibly burn nuclear wastes, revived in the late 1970's, when the LMFBR came under attack during the Carter administration. This period gave the opportunity to revisit the concept in view of the present state of the technology. This evaluation and the extensive calculational modeling of target designs that have been carried out are promising. In fact, a nuclear fuel cycle of Light Water Reactors and Accelerator Breeders is competitive to that of the LMFBR. At this time, however, the relative abundance of uranium reserves vs electricity demand and projected growth rate render this study purely academic. It will be for the next generation of accelerator builders to demonstate the competitiveness of this technology versus that of other nuclear fuel cycles, such as LMFBR's or Fusion Hybrid systems. 22 references, 1 figure, 5 tables.

  11. Overview of EU activities on DEMO liquid metal breeder blanket

    SciTech Connect

    Giancarli, L.; Proust, E.

    1994-12-31

    The European test-blanket development programme, started in 1988, is aiming at the selection by 1995 of two DEMO-relevant blanket lines to be tested in ITER. At present, four lines of blanket are under development, two of them using solid and the other two liquid breeder materials. As far as liquid breeders are concerned, two lines of blankets have been selected within the European Union, the water-cooled lithium-lead (the eutectic Pb-17Li) blankets and the dual-coolant Pb-17Li blankets. Designs have been developed considering an agreed set of DEMO specifications, such as, for instance, a fusion power of 2,200 MW, a neutron wall-loading of 2MW/m{sup 2}, a life-time of 20,000 hours, and the use of martensitic steel as a structural material. Moreover, an experimental program has been set up in order to address the main critical issues for each line. The present paper gives an overview of both design and experimental activities within the European Union concerning these two lines of liquid breeder blankets.

  12. Investigation of the mechanical properties of ceramic breeder materials

    NASA Astrophysics Data System (ADS)

    Dienst, W.; Zimmermann, H.

    1988-07-01

    In order to characterize ceramic breeder materials for fusion reactors, mechanical properties were measured on Li 2SiO 3, Li 4SiO 4, and also on some LiAlO 2 samples for comparison. Literature data on thermal conductivity and thermal expansion of all breeder materials considered were compiled to compare their presumable sensitivity to thermal stresses. The highest level of thermal shock resistance is predicted for LiAlO 2, and the lowest level for Li 4SiO 4. Thermal shock tests, made by dipping pellets into a hot metal melt, confined the relation for LiAlO 2 and Li 4SiO 4. Young's modulus was determined by ultrasound velocity measurement, and fracture strength was measured on pellet samples under compression. The scatter in compressive strength is exceptionally large, partly due to various grain size, and does not suggest a definite ranking of the different breeder materials. Compressive creep tests were made at temperatures of 750-950°C for about 100 h each. An extrapolated creep rate of 10 -6/h was used to estimate a conservative temperature limit of total microstructure stability.

  13. Gas core reactors for actinide transmutation and breeder applications

    NASA Technical Reports Server (NTRS)

    Clement, J. D.; Rust, J. H.

    1978-01-01

    This work consists of design power plant studies for four types of reactor systems: uranium plasma core breeder, uranium plasma core actinide transmuter, UF6 breeder and UF6 actinide transmuter. The plasma core systems can be coupled to MHD generators to obtain high efficiency electrical power generation. A 1074 MWt UF6 breeder reactor was designed with a breeding ratio of 1.002 to guard against diversion of fuel. Using molten salt technology and a superheated steam cycle, an efficiency of 39.2% was obtained for the plant and the U233 inventory in the core and heat exchangers was limited to 105 Kg. It was found that the UF6 reactor can produce high fluxes (10 to the 14th power n/sq cm-sec) necessary for efficient burnup of actinide. However, the buildup of fissile isotopes posed severe heat transfer problems. Therefore, the flux in the actinide region must be decreased with time. Consequently, only beginning-of-life conditions were considered for the power plant design. A 577 MWt UF6 actinide transmutation reactor power plant was designed to operate with 39.3% efficiency and 102 Kg of U233 in the core and heat exchanger for beginning-of-life conditions.

  14. Hatchability of Broiler Breeder Eggs Following Eggshell Sanitization by Repeated Treatment with a Combination of Ultraviolet Light and Hydrogen Peroxide

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Previous research has indicated that a single exposure of eggs to ultraviolet light (UV) in combination with 3% hydrogen peroxide (H2O2) results in a greater reduction of eggshell bacteria compared to eggs treated with either UV or H2O2 alone. The objective of this study was to determine if hatcha...

  15. Evaluation of jojoba meal as a potential supplement in the diet of broiler breeder females during laying.

    PubMed

    Vermaut, S; De Coninck, K; Bruggeman, V; Onagbesan, O; Flo, G; Cokelaere, M; Decuypere, E

    1999-05-01

    1. This study was undertaken to investigate whether jojoba meal can be used as a food supplement during the laying period of chickens. 2. The size of eggs laid were smaller and the overall production rate was lower compared to control birds on food without jojoba meal supplementation. Furthermore, both ovary and oviduct weights were lower in jojoba fed birds. 3. This lowering of egg size and production rate was caused by factors present in jojoba which interfere with follicle growth, yolk deposition, progesterone production and the follicular maturation processes, resulting in the ovulation of smaller follicles and a lower ovulation rate.

  16. Prevalence and distribution of Salmonella in organic and conventional broiler poultry farms.

    PubMed

    Alali, Walid Q; Thakur, Siddhartha; Berghaus, Roy D; Martin, Michael P; Gebreyes, Wondwossen A

    2010-11-01

    The objective of this cross-sectional study was to compare the prevalence of Salmonella and antimicrobial-resistant Salmonella, as well as investigate the distribution of this pathogen in organic and conventional broiler poultry farms. Fecal (n = 420), feed (n = 140), and drinking water (n = 140) samples were collected from birds at 3 and 8 weeks of age for 2-flock cycles. One house was sampled per farm at three organic and four conventional broiler farms from the same company in North Carolina. All samples were analyzed for the presence of Salmonella using selective enrichment techniques. Further phenotypic (antimicrobial susceptibility) and genotypic (pulsed-field gel electrophoresis [PFGE]) testing were performed. Salmonella prevalences in fecal samples were 5.6% (10/180) and 38.8% (93/240) from organic and conventional farms, respectively. From feed, 5.0% (3/60) and 27.5% (22/80) of the samples were positive for Salmonella from organic and conventional farms, respectively. None of the water samples were positive for Salmonella. Seventy isolates were characterized by antimicrobial susceptibility and PFGE types. The two most common resistance phenotypes were single resistance to streptomycin (36.2% [25/58]: conventional; 25% [3/12] organic), and multidrug resistance to six antimicrobial agents: ampicillin-streptomycin-amoxicillin/clavulanic acid-cephalothin-ceftiofur-cefoxitin (AmStAxChCfFx; 39.7%: conventional only). Genotypic analysis using PFGE showed clonality among isolates within and between the two types of farms. The results of our study suggest that within this poultry company, the prevalence of fecal Salmonella was lower in certified-organic birds than in conventionally raised birds, and the prevalence of antimicrobial-resistant Salmonella was also higher in conventionally raised birds than in certified-organic birds.

  17. Structure and dynamics of mixed-species flocks in a Hawaiian rain forest

    USGS Publications Warehouse

    Hart, P.J.; Freed, L.A.

    2003-01-01

    Mixed-species flocks of native and introduced birds were studied for four years in an upper elevation Hawaiian rain forest. Those flocks were characterized by strong seasonality, large size, low species richness, high intraspecific abundance, a lack of migrants, and a general lack of territoriality or any sort of dominance hierarchy. There was high variability among years in patterns of occurrence at the species level, and high variability within years at the individual level. These flocks are loosely structured social groupings with apparently open membership. The fluid, unstable movement patterns, high degree of variability in size and composition, and lack of positive interspecific associations are not consistent with the "foraging enhancement" hypothesis for flocking. Two resident, endangered insectivores, the Akepa (Loxops coccineus) and Hawaii Creeper (Oreomystis mana) served as "nuclear" species. Flock composition was compared between two study sites that differed significantly in density of these two nuclear species. Flock size was similar at the two sites, primarily because the nuclear species were over-represented relative to their density. This observation suggests that birds are attempting to achieve a more optimal flock size at the lower density site.

  18. Flocking at a distance in active granular matter.

    PubMed

    Kumar, Nitin; Soni, Harsh; Ramaswamy, Sriram; Sood, A K

    2014-01-01

    The self-organized motion of vast numbers of creatures in a single direction is a spectacular example of emergent order. Here, we recreate this phenomenon using actuated nonliving components. We report here that millimetre-sized tapered rods, rendered motile by contact with an underlying vibrated surface and interacting through a medium of spherical beads, undergo a phase transition to a state of spontaneous alignment of velocities and orientations above a threshold bead area fraction. Guided by a detailed simulation model, we construct an analytical theory of this flocking transition, with two ingredients: a moving rod drags beads; neighbouring rods reorient in the resulting flow like a weathercock in the wind. Theory and experiment agree on the structure of our phase diagram in the plane of rod and bead concentrations and power-law spatial correlations near the phase boundary. Our discovery suggests possible new mechanisms for the collective transport of particulate or cellular matter.

  19. A Density-Independent Flocking Transition in Confluent Tissues

    NASA Astrophysics Data System (ADS)

    Czajkowski, Michael; Bi, Dapeng; Manning, M. Lisa; Marchetti, M. Cristina

    Some of us recently demonstrated a density-independent solid-liquid transition in confluent tissues controlled by cell motility and a cell shape parameter measuring the interplay of cortical tension and cell-cell adhesion. An important insight of this work is that the rigidity and dynamics of cell layers depends sensitively on cell shape. To explore the influence of cell shape on collective states, we have constructed continuum equations that couple a scalar field describing cell-shape anisotropy to cell polarization. The model displays a density independent transition to a polarized state of elongated cells driven by a cellular ``shape-index'' parameter. We map out the phase diagram using linear stability analysis and numerical solution of the nonlinear hydrodynamic equations. The proposed transition constitutes a density-independent flocking transition. We acknowledge support from The Simons Foundation and NSF-DGE-1068780.

  20. Adaptive Flocking of Robot Swarms: Algorithms and Properties

    NASA Astrophysics Data System (ADS)

    Lee, Geunho; Chong, Nak Young

    This paper presents a distributed approach for adaptive flocking of swarms of mobile robots that enables to navigate autonomously in complex environments populated with obstacles. Based on the observation of the swimming behavior of a school of fish, we propose an integrated algorithm that allows a swarm of robots to navigate in a coordinated manner, split into multiple swarms, or merge with other swarms according to the environment conditions. We prove the convergence of the proposed algorithm using Lyapunov stability theory. We also verify the effectiveness of the algorithm through extensive simulations, where a swarm of robots repeats the process of splitting and merging while passing around multiple stationary and moving obstacles. The simulation results show