Abstract/Summary

Foot pad dermatitis (FPD) in poultry is a contact dermatitis that can be painful and has a negative impact on bird welfare and performance. The primary cause is wet litter and so any factors which may cause the litter to become wet (eg poor choice of bedding material, dietary imbalances and poor gut health) may increase the risk of the birds developing FPD . In this thesis, various nutritional and management interventions were investigated to determine their impact on bird performance, aspects of gut and foot health and function, and measures of litter quality. When turkeys were fed whole grain wheat (WGW), either as free choice or mixed with the diet at inclusion rates up to 200 g/kg diet, it was observed that intake of WGW was much more variable in birds offered free choice WGW, although mean intake of WGW was greater. Bird performance was better if WGW was not fed, but if WGW was included in the diet, performance was better when WGW was mixed into the diet rather than offered free choice. WGW reduced gizzard pH, which might inhibit the growth of pathogens in the gut, but at a molecular level it had no effect on the presence of Clostridium perfringens, Campylobacter jejuni, Salmonella spp or Brachyspira pilosicoli. It also had no effect on litter moisture content or incidence of foot pad dermatitis. When broilers were reared on different bedding materials (Envirobed or wood shavings), bird weight was greater if broilers were kept on wood shavings, but birds consumed more Envirobed bedding and this was associated with drier digesta so that the risk of FPD might be lower with Envirobed. Broilers were then fed either a wheat or maize based diet and reared on wood shavings which were either clean or had excreta from mature laying hens added. There was effect on bird performance, but feeding maize may reduce the risk of FPD as it was associated with reduced litter ammonia content, increased litter pH and decreased prevalence of ampicillin resistant E. coli in both the birds’ gut and the litter. Litter quality is improved (and FPD reduced) if birds are encouraged to consume bedding (or a high fibre feed) and fed maize rather than wheat. The finding of this thesis are that, to reduce the risk of foot pad dermatitis in broilers and turkeys, the birds’ litter must remain dry and friable. This will be achieved by adequate ventilation and good management of drinkers, but also by maintaining good gut health in the birds. In this thesis, drier excreta and litter were associated with higher bedding (or fibre) consumption, and by feeding birds maize rather than wheat.