Rapid diagnostics and control strategies for enteric bacterial pathogens in backyard and commercial poultry production in Thailand and the Philippines

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In many Low to Middle Income Countries (LMICs) poultry meat and eggs are produced in small scale flocks using indigenous breeds of birds. This contrasts with countries that produce meat in large commercial units using chicken strains specifically bred for use in highly controlled environmental conditions with maximal meat production in as short a time as possible. Indigenous breeds are cross-bred and produce fewer eggs and less meat than their commercial equivalent but are are an important source of food at the family or local community level. However, due to differences in regulatory practices, the use of antimicrobials (AMs) as growth promoters is prevalent which limits future commercial development and promotes the spread and maintenance of antimicrobial resistance. The use of AMs needs to be reduced by the provision of alternative growth promoters. Commercial breeding programmes have resulted in broilers that preferentially deposit muscle (ie breast meat) over allocating proteins toward other processes, including, probably, the immune response. Under commercial conditions of good biosecurity, optimised high nutrient diets over short timescales in highly controlled conditions, commercial birds are very productive. In contrast, indigenous birds are smaller, have a lower nutrient demand and are immunologically more robust; they are however, far less productive. This combination of differing bird genetic background and nutritional requirements along with potentially different immunological responses and intestinal microflora means that poultry disease susceptibility and the potential for colonisation by zoonotic pathogens may be different in indigenous birds. We wish to determine if Indigenous breeds of poultry and modern hybrid birds differ in their genetics, gut microbiome and immunological parameters and establish if these differences associated and if they can be exploited for disease control and management. The major bacterial zoonotic pathogens, Salmonella enterica and Campylobacter jejuni, frequently colonise poultry and consequently present a very significant human health risk due to contamination of meat or eggs. In addition, certain types of S. enterica (the serovars Pullorum and Gallinarum) also present a disease risk to chickens, affecting the health and welfare of the flock. Our aim is to characterise the infection of an indigenous breed of chicken in backyard flocks to determine how infection modulates the composition of the bacterial community living in the chicken gut and the AM resistance genes that are present. In addition, we will characterise how the immune response of the indigenous birds responds to infection. We will use this information to develop a probiotic to competitively exclude Salmonella and/or Campylobacter and also develop a cheap and simple test for the presence of different types of Salmonella in backyard flocks. This project will provide both commercial and backyard producers with a much-needed management tool to reduce the disease burden and health risk associated with poultry products.