The productive performance in 49-day broilers fed diets supplemented with protein additives based on keratin- and collagen-containing poultry wastes
The efficiency of the supplementation of diets for broilers with feed-grade protein additives based on the keratin- and collagen-containing poultry wastes and produced by short-term thermal treatment and subsequent enzymatic hydrolysis was studied on four treatments of Ross-308 broilers (50 birds per treatment) raised on the floor to 49 days of age. Control treatment was fed a diet with fishmeal as animal protein source; experimental treatments were fed diets where fishmeal was substituted by the additives mentioned above with or without additional supplementation with a probiotic. It was found that the productive performance in all experimental treatments was higher in compare to control; mortality levels in all experimental treatments were 0% while in control 2%. The best results were found in the treatment fed keratin-derived additive and a probiotic. Live bodyweight at 49 days of age in this treatment was significantly higher by 9.0% (P<0.001) in compare to control while feed conversion ratio was better by 8.1%.