LAUSR

This study investigated the effects of recycled poultry bedding (RPB) on performance and protozoa population, microbial enzyme activity and microbial protein synthesis (MPS) in rumen contents of fattening lambs. Thirty-six male Moghani lambs (31.4 ± 3.2 kg body weight) were fed iso-energetic and iso-nitrogenous diets containing 0, 70, 140 or 210 g/kg dry matter (DM) RPB in a balanced randomized design (9 lambs per treatment). Results showed that final body weight, DM intake, average daily gain and feed conversion ratio were unchanged (P > 0.05) by RPB inclusion. Total protozoa population and sub-family of Entoniniinae and Diplodiniiae were linearly decreased by RPB (L, P < 0.05). For rumen fibrolytic enzymes including carboxymethyl-cellulase, microcrystalline-cellulase and filter paper degrading activity, the extra cellular, cellular and total (extra cellular plus cellular fraction) activity were similar (P > 0.05) by feeding the experimental diets. Inclusion of RPB in the diet linearly decreased extra cellular and total α-amylase activity (L, P < 0.05), while cellular activity was unchanged (P > 0.05). The extra cellular activity of proteases tended to increase (L, P = 0.07) and their total and cellular activity increased (P > 0.05) in lambs fed RPB. Incorporation of RPB into the diet had no effect (L, P > 0.05) on urinary purine derivative excretion and MPS. In conclusion, inclusion of RPB up to 210 g/kg DM had no negative impact on performance, ruminal fibrolytic enzyme activity and MPS, while it increased rumen protease activity and decreased protozoa population in fattening Moghani lambs.