Evaluation of Chicken Feathers Degraded by Keratinase for Poultry Feed Supplement

Chicken feathers pose a significant environmental challenge due to their high resistance to natural degradation. It accumulates in the environment and constitutes serious problems to human health. The study was conducted to degrade chicken feathers by keratinase from selected bacteria isolated from soil samples containing chicken feather waste and the resulting hydrolysate used as a supplement in broiler feeds. Feather waste was milled and degraded with the isolated bacteria. Thereafter, 4-week-old broilers were grouped into six groups and fed for four weeks. The first group was the positive control, fed with commercial feed; the second group was the negative control, fed without hydrolysate. The third, fourth, fifth, and sixth groups were fed 5% and 10% hydrolysate from two different degraded feathers, respectively, and their weights were taken daily. The blood sample of the experimental broilers were collected for the liver function test. The mean weight of the broilers fed without hydrolysate increased from 0.661 kg to 2.954 kg, while the broilers fed with hydrolysate increased from 0.650 kg to 3.013 kg after four weeks. The ranges of liver function test parameters are aspartate transaminase (73.00-105.00 U/l; Alanine transaminase (10.00-17.00 U/L); Albumin (11.50-13.50 g/l); Total Protein (35.00-40.50 g/l); total bilirubin (14.40-23.65 umol/l); conjugate bilirubin (1.10-2.45 umol/l). The liver function test reveals that the supplement produced from degraded feathers is safe for broiler consumption. Therefore, Serratia nematodiphila and Klebsiella pneumoniae might be used for large-scale production of keratinase for industrial purposes and to enhance broiler feed nutrients.