Influence of Enzymatically Treated Feather Meal as a Protein Source on Starter Broiler Performance and Carcass Yield
The rising cost and increasing competition for conventional protein sources such as fishmeal and soybean meal in poultry nutrition have intensified the search for alternative, sustainable, and cost-effective feed ingredients. Poultry feathers, an abundant by-product of the poultry processing industry, contain over 90% crude protein, primarily in the form of keratin. However, the indigestibility of native keratin poses a major limitation to its use in poultry diets. This study investigated the potential of enzymatically treated feather meal (ETFM) as a replacement for fishmeal in broiler chicken diets, with a focus on growth performance, carcass yield, and histopathological safety. A total of 150 day-old broiler chicks (ROSS 308) were randomly allocated into five dietary treatment groups (T1–T5), each with three replicates of 10 birds. The treatment diets were formulated to replace fishmeal with ETFM at 0% (T1, control), 25% (T2), 50% (T3), 75% (T4), and 100% (T5) inclusion levels. The feather meal used in the study was hydrolysed using a crude keratinase enzyme extracted from Streptomyces fradiae, a keratinolytic bacterium isolated from poultry waste soil. The study spanned 56 days, with feed intake, body weight gain, and feed conversion ratio (FCR) recorded weekly. At the end of the trial, carcass characteristics, including live weight, dressed weight, breast muscle yield, and internal organ weights, were assessed. Results showed that ETFM could successfully replace fishmeal up to 75% without adverse effects on feed intake, weight gain, or FCR. Birds in T2 (25% ETFM) and T3 (50% ETFM) exhibited significantly (p < 0.05) better FCR and comparable weight gain to the control group, indicating efficient nutrient utilisation. Carcass evaluation revealed no significant differences (p > 0.05) in dressing percentage, breast muscle yield, thigh, drumstick, or internal organ weights among the treatment groups, although a slight decline in carcass yield was observed in T4 and T5 groups. This study concludes that enzymatically treated feather meal is a viable, safe, and cost-effective alternative to fishmeal in broiler diets. The use of ETFM up to 75% inclusion supports optimal growth performance and carcass quality without deleterious effects on organ integrity or tissue health. Adopting enzymatic processing enhances the digestibility and functional value of feather meal, offering a sustainable solution for poultry feed formulation while reducing environmental pollution associated with feather waste disposal. Future studies are recommended to evaluate the long-term implications of ETFM on nutrient digestibility, immune response, and meat quality traits in broilers
