Effect of yeast culture supplementation on nutrient digestibility and fattening performance of awassi rams fed different levels of straw containing diets

Abstract

Two apparent digestion trials, an in-vitro trial and a fattening trial were conducted to evaluate the effect of yeast culture (YC). In trial I and II, nine 3 years old Awassi rams were allocated for three treatments at random. In trial I, 0, 5 and 10 g/d of a YC was supplemented to a basal diet containing 70% wheat straw (WS) and 30% commercial concentrate pelleted feed (CCPF) with low CP level (12%). In trial II, 0, 10 and 20 g/d of a YC was supplemented to a basal of 30% WS and 70% CCPF with high CP level (16 %). In trial III, in vitro dry matter disappearances (IVDMD) of alfalfa hay (AH), WS, CCPF with low and high CP levels were determined using two inoculants with or without YC supplementation (20gId/ram). In trial IV, 12 Awassi lambs (5-6 month old) were equally allotted among dietary treatments for control and 10 g/d YC supplementation groups. Yeast culture supplementation did not change DM and OM digestibility in both in vivo digestion trials (P>0.05), but IVDMD of AH, WS and CCPF with high CP improved with YC supplementation (P<0.05). While digestibility of ADF and CP was decreased with 10 g/d YC supplementation in trial 1, digestibility of NDF and CP was improved (P<0.05) with 20g/d YC supplementation in trial 2. The YC supplementation of 20g/d in trial 2 increased ruminal pH and NH3-N. In fattening trial, YC supplementation had no effect. Thus, there was no advantage of supplementing YC on DM and OM digestibility of diets and fattening performance of Awassi lambs. © GSP, India.