The generation of poultry slaughterhouse wastes (PSW) obtained from poultry production fowl is not only unavoidable but the amount and kinds of waste which consists of protein-rich organic residues can cause environmental problems. In the present study, the potential rumen digestion of PSW was evaluated. Chemical composition, amino acid profile and Cornell Net Carbohydrate and Protein System fractionating of these wastes were determined. Rumen digestion of PSW was compared with two common protein sources (fish meal; FM and roasted soybean; RSB). Three PSW samples were collected from industrial poultry slaughter-houses and the in situ degradation was done using rumen cannulated sheep. The protein (50-63%), ether extracts (18-27%) and ash (9-15.5%) contents of different PSW samples were different (P < 0.05). The protein fractions (B1, B3 and C) of sources were influenced either (P < 0.05); however there was no difference for A as well as B2 fractions. Methionine and lysine contents were similar among different PSW sources. Difference were observed for cystine (1.2-1.7%), threonine (1.9-2.2%), arginine (3-3.5%), leucine (3.5-4.1%) and valine (2.8-3.3%) (P < 0.05). Ruminal degradation rate for dry matter, organic matter and protein were different among PSW, FM and RSB. The degradation parameter (a+b) for protein degradation was 76% for PSW, 79% for FM and 98% for RSB (P < 0.05). Results revealed that there was great variation in chemical composition, protein fractioning, and amino acid profiles of different PSW sources. Poultry slaughterhouse waste is slowly-degraded protein in the rumen and thus an economical and rich source of rumen un-degradable protein in ruminant nutrition. This implies that poultry slaughterhouse waste has a huge potential as a cleaner product of animal feeding and prevention environmental pollution. However, further studies are warranted to evaluate the digestibility of PSW amino acids escaping the rumen into the intestine in ruminants and to com
