| dc.description.abstract | Background: Campylobacteriosis is the most frequently reported foodborne disease in the EU since 2005. Monitoring at Dutch slaughterhouses revealed that 44.5% of broiler flocks tested positive for Campylobacter spp. Because approximately 80% of human campylobacteriosis cases are related to strains from the chicken reservoir, reducing the number of Campylobacter colonized flocks will have a significant contribution to public health.
Aim of study: The aim of this study was to compare two broiler housing systems, the Patio system (Vencomatic Group, Eersel, the Netherlands) and conventional poultry floor housing systems, for the presence of Campylobacter spp. The hypothesis was that introduction of Campylobacter is less likely to occur in Patio systems than in conventional broiler housing systems, because of specific differences in biosecurity regarding the number of insects and intensity of human traffic, especially around thinning of the flock.
Materials and methods: Four Patio systems were matched to four control houses and progeny of the same broiler breeder flock was placed in both housing systems at approximately the same time. A questionnaire with specific Campylobacter related biosecurity questions (CAMPAS checklist) filled out by the farmer was used to assess the level of biosecurity on all farms. Two rounds of sampling of cecal droppings were performed, around day 28, before partial thinning and day 38, after partial thinning. Sticky flytraps were placed in all broiler houses for 14 days to evaluate the number of insects.
Results and discussion: The CAMPAS checklist revealed that biosecurity risk levels were scored lower by farmers of Patio systems (on average 4.0) than by farmers of conventional broiler houses (10.7). Broiler flocks on all farms tested negative for the presence of Campylobacter during the first round of sampling. At the second round of sampling, all four Patio systems tested negative, whereas one out of four control houses was Campylobacter jejuni positive. Although the difference in the proportion of positive houses of 0.25 (25%) between both housing systems was statistically significant, the actual difference in Campylobacter prevalence for Patio systems versus conventional broiler houses may range between 0.6% and 80.6% at 95% confidence level. Consequently, more flocks need to be sampled to accurately compare prevalence in both housing systems. Insects were present in both types of housing systems. Category 3 insects (with sizes between 5-10 mm), that may comprise flies that are known to be able to transfer Campylobacter to the broiler flock, were present in both housing systems. The mean differences in insects caught between the housing systems in both weeks and the number of category 3 insects were not statistically significant. Therefore it cannot be concluded that there is an actual difference between the housing systems in terms of the number of insects. In the past years the relationship between biosecurity and the introduction of Campylobacter in broiler flocks has been well established. However, it is also recognized that biosecurity alone cannot ensure Campylobacter negative flocks. Therefore studies into complementary measures to reduce colonization of broilers with Campylobacter should be conducted. Further research with regard to the occurrence of Campylobacter in Patio systems and conventional broiler housing systems is recommended. | |
