The Effect of Alternative Feeding Strategies for Broiler Breeder Pullets throughout the Production Cycle
Feeding management of broiler breeders is a controversial issue for the poultry industry. Feeding broiler breeders to satiety results in obesity-related problems and feed restriction is a welfare concern as feed-restricted broiler breeders show signs of chronic hunger, feeding frustration and lack of satiety. The development of alternative diets has focused on dietary dilution and the addition of an appetite suppressant. Furthermore, many producers in Canada use non-daily feeding schedules to feed-restrict broiler breeders, a practice banned in some countries due to the perceive threat toward welfare. Yet, there is little empirical data on the implications of alternative feeding strategies for the welfare of broiler breeders. The objective of this thesis was to determine the effect of alternative diets and non-daily feeding schedules on broiler breeder welfare and productivity. Results in this thesis indicated advantages and disadvantages to all feeding strategies, and pullets remained highly-feed motivated regardless of the feeding strategy. Those fed the control diet daily were more active, performed more stereotypic and abnormal behaviours, had worse feather coverage, and were more feed motivated than those on the alternative diet or fed non-daily during early rearing. Hens reared on the alternative feeding strategies showed a higher laying persistency than control hens, reflected in a higher cumulative egg production. Pullets fed non-daily may achieve a greater feeling of satiety during on-feed days but displayed behavioural signs of hunger during off-feed days. The inclusion of soybean hulls alleviated stress and acted as an intestinal filler but resulted in a higher intestinal water content, wetter litter, foot lesions, and more intestinal lesions compared to the control diet. Our results indicate that non-daily feeding does not appear worse than daily feed restriction for broiler breeder welfare but off-feed days are an ethical concern. Alternative diets containing soybean hulls and calcium propionate reduced some signs of chronic hunger but raised other welfare concerns.