Impact of feeding a high fiber diet and roughage on stress and clinical welfare indicators in fast-growing broiler breeder pullets.

Qualitative feed restriction has been proposed as a means to alleviate hunger, frustration, and stress associated with feed restriction in broiler breeder chickens. The aim of this study was to investigate the effect of a fiber-rich diet containing oat-hulls and a daily allocation of roughage (EXP) compared to a standard commercial diet (CON) on broiler breeder welfare. A total of 600 day-old female Ross 308 breeder chicks were allocated to 12 pens of 50 birds each, with each pen receiving one of the two dietary treatments. At the conclusion of the study, a welfare assessment was performed which included assessing plumage damage, wounds/scratches, footpad dermatitis, bumblefoot, hock burns, plumage cleanliness, and body weight. Wing, scapula, and tail feathers were collected and examined following euthanasia for presence and severity of fault bars. Litter quality was assessed visually every other week throughout the study period, and samples were collected at weeks 6, 12, and 18 to assess moisture content. Mortality was also documented throughout the study. Body weight uniformity, litter quality, and mortality did not differ between treatments. CON birds had poorer plumage quality (P < 0.0001), greater occurrence of hyperkeratosis (P < 0.0001), were more likely to have poorer hock burn scores (P = 0.0104) and were more likely to have dirtier plumage (P = 0.0075) than birds in the EXP treatment. CON birds had a greater number of fault bars (P < 0.0001) and greater occurrence of severe fault bars (P= 0.039) on their scapula feathers than EXP birds. Feather growth rate was also lower in the CON treatment for scapula feathers (P = 0.0305). In conclusion, results from our study show that feeding a diet high in insoluble fiber and supplemented with roughage appears to provide some improvements to broiler breeder welfare during rearing compared to feeding a standard commercial diet.