The impact of biosecurity and partial depopulation onCampylobacterprevalence in Irish broiler flocks with differing levels of hygiene and economic performance (original) (raw)

Campylobacter spp. in conventional broiler flocks in Northern Ireland: Epidemiology and risk factors

Preventive Veterinary Medicine, 2008

Risk factors for Campylobacter infection in conventional broiler flocks in the time period up to the first removal of birds to slaughter were investigated over a maximum of five consecutive production cycles in a cohort of 88 broiler farms in Northern Ireland. Samples for Campylobacter culture, which consisted of 14 cloacal swabs per flock, were collected from one house on each farm prior to the first depopulation of birds. In total 388 flocks were sampled, of which 163 tested positive for Campylobacter spp. (42.0%; 95% CI 35.1-48.9%).

Risk factors for Campylobacter colonisation during rearing of broiler flocks in Great Britain

Preventive veterinary medicine, 2009

We investigated the associations between Campylobacter colonisation and management practices and farm characteristics in 603 housed broiler batches originating from 137 farms in Great Britain. All study batches were the initial batch slaughtered from the selected house on enrolled farms. Between 1 and 15 batches were sampled from each farm throughout the study. A total of 34.2% of the batches was Campylobacter positive and multivariable multilevel logistic regression revealed that the risk of Campylobacter colonisation was highest in July (OR=3.4, CI95%:1.8; 6.4), August (OR=3.4, CI95%:1.9; 6.2) and September (OR=3.7, CI95%:1.9; 7.1). Cattle on or adjacent to the farm increased the risk (OR=1.7, CI95%:1.1; 2.7), whereas chlorinated drinking water reduced it (OR=0.5, CI95%:0.2; 0.9). If the first removed batch from the previous flock in the house had been Campylobacter positive, the first batch of the following flock was also more likely to be colonised (OR=3.2, CI95%:2.1; 4.9). This...

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

Acta Veterinaria Scandinavica, 2007

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

Comparison of Campylobacter spp. and flock health indicators of broilers in Iceland

Annals of Agricultural and Environmental Medicine

Introduction. The safety of poultry meat products and contamination with microorganisms is based on appropriate reduction of the presence of pathogens during poultry rearing and is closely related to the level of rearing hygiene, including the type of housing, stocking density, microclimate, sanitation and ventilation. Objective. The aim of the study is to evaluate the prevalence of Campylobacter-positive samples in Iceland during 2016-2018, and to compare the potential influence of individual parameters of welfare on the prevalence of Campylobacter spp. Materials and method. Positivity of excrement and caecum samples for Campylobacter spp. was determined according to ISO 10272-1: 2006 and 2017. Data of welfare indicators were collected during the rearing period and in the slaughterhouse. Results. Considerable seasonality was observed in the prevalence of Campylobacter spp. The prevalence of campylobacteriosis on the investigated broiler farms was significantly higher (p˂0.05) during the summer. Comparison of welfare parameters on Campylobacter-positive and Campylobacter-negative farms failed to indicate a significantly higher level of observed welfare indicators in birds from Campylobacter-positive farms (p˃0.05). In comparing small, medium and big farms, a significantly higher occurrence was observed (p<0.05) of the FPD score over 40, stocking density, and the average slaughter weight, and percentage of mortality over 2% in small farms. Conclusions. Intensive management and the environment affect the welfare of poultry and its resistance to infections (Campylobacteriosis) and thus increase the health risk. Checking the welfare parameters in a slaughter house provides delayed improvement of the environment on farms, but it can also lead to changes in the following production cycles (decreasing of stocking density).

Risk Factors Associated with the Presence of Campylobacter Species in Norwegian Broiler Flocks

Poultry Science, 2008

A case-control study was conducted in 2005 to identify risk factors for the presence of Campylobacter spp. in Norwegian broiler flocks. A total of 131 broiler farms (44 cases and 87 controls) were included in the study, and 1 flock from each farm was included in the statistical analyses. Data on farm and flock level were collected by means of a questionnaire designed for the present study. The relationship and strength of association between the presence of Campylobacter spp. in the broiler flocks and several factors were in-vestigated by unconditional logistic regression. The following factors were found to be associated with an increased risk of testing positive for Campylobacter spp.: water from a private water source, swine holdings closer than 2 km, a specific slaughterhouse, a hired animal caretaker, transport personnel passing through the hygiene barrier when delivering day-old chickens, less than 9 d between depopulation and restocking, and multiple broiler houses on the farm.

Correlations between Campylobacter spp. prevalence in the environment and broiler flocks

Journal of applied microbiology, 2007

To investigate (i) possible correlations between the presence of Campylobacter spp. in the surroundings of broiler farms and their incidence in flocks, and (ii) possible associations between weather conditions and the occurrence of Campylobacter spp. Farms were selected according to previous results from the Swedish Campylobacter programme. Samples were collected in and around broiler houses during the rearing period from 131 flocks on 31 farms, including sock samples from the ground outside, from the floor in the broiler houses and anterooms, and samples from insects, water, feed and ventilation shafts. As expected, there was a difference in Campylobacter isolation rates for different categories of farms regarding samples taken in the houses. However, there were no differences regarding the presence of Campylobacter spp. in the environment between producers that often deliver Campylobacter-positive slaughter batches and those that rarely deliver positive batches. Campylobacter spp....

Flock Health Indicators and Campylobacter spp. in Commercial Housed Broilers Reared in Great Britain

Applied and Environmental Microbiology, 2008

This study investigated the relationship between flock health and Campylobacter infection of housed commercial broilers in Great Britain. Thirty ceca were collected at slaughter from batches of broilers from 789 flocks, at either full or partial depopulation, between December 2003 and March 2006 and examined individually for Campylobacter by direct plating onto selective media. Management and health data were collected from each flock and included information on mortality or culling during rearing, the number of birds rejected for infectious or noninfectious causes at slaughter, the proportion of birds with digital dermatitis (also termed hock burn), and other general characteristics of the flock. Campylobacter spp. were isolated from 280 (35%) flocks. The relationship between bird health and welfare and Campylobacter status of flocks was assessed using random-effects logistic regression models, adjusting for region, month, year, and rearing regime. Campylobacter-positive batches of ceca were associated with higher levels of rejection due to infection (odds ratio [OR], 1.5; 95% confidence interval [CI 95% ], 0.98 to 2.30) and digital dermatitis (OR, 2.08; CI 95% , 1.20 to 3.61). Furthermore, higher levels of these conditions were also associated with the highest-level category of withinflock Campylobacter prevalence (70 to 100%). These results could indicate that improving health and welfare may also reduce Campylobacter in broilers.

Risk factors and likelihood of Campylobacter colonization in broiler flocks

Brazilian Journal of Poultry Science, 2007

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

The Prevalence of Campylobacter amongst a Free-Range Broiler Breeder Flock Was Primarily Affected by Flock Age

PLoS ONE, 2011

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.

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

Preventive Veterinary Medicine, 2007

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.