Assessment of risk factors and prevalence of campylobacter and salmonella in chickens under different production systems

A Dissertation Submitted in Partial Fulfillment of the Requirements for the Degree of Master’s in Life Sciences of the Nelson Mandela African Institution of Science and TechnologyThe human population growth and increased urbanization in Tanzania, stimulates emerging of new livestock systems with variable intensification levels. In poultry production, traditional free-range backyard farming is now complemented by a range of intensive production systems. Intensification of poultry production may result in opportunities and threats with regards to food safety, e.g. in contamination of poultry with food borne pathogens such as Campylobacter species or non-typhoid Salmonella (NTS) species. The aim was to conduct cross sectional study across ten wards of Arusha district, northern Tanzania to assess risk factors and prevalence of these pathogens in emerging poultry production systems. Semi-quantitative analysis of chicken production systems with emphasis on biosecurity, health management practices and prevalence of food borne pathogens was done from September 2016 to January 2017. Interviews were conducted with 40 farmers, with equal representation of 4 production systems, 255 and 386 birds were screened for cloacae shedding of Campylobacter and NTS species respectively. Farm level prevalence of Campylobacter and NTS species was 57.7% (15/26) and 15% (6/40), respectively. Differences were observed between farms with regards to implementation of biosecurity and health management practices as well as use of extension services. By contrast, prevalence of food borne pathogens was not farm-type specific, indicating that it is driven by other risk factors. Moreover, Multiple Component Analysis showed that risk factors associated with Campylobacter prevalence differ from those associated with Salmonella. Results can be used to inform on-farm food safety practices and the use of extension services, from all stake holders