Influence of diet supplementation with yeast culture (Saccharomyces cerevisiae) on performance of Zaraibi goats

This study was conducted to evaluate the effect of supplementing different levels of yeast culture (YC) in Zaraibi goats' diets on digestibility, milk yield and composition, rumen activity and performance of Zaraibi goats during the lactation period. Fifteen Zaraibi does in the first and second lactation, 12-24 months of age, and weighing in average 32.50 kg were randomly divided into three equal groups. The control group (T1) was fed a concentrate mixture and roughage (alfalfa and wheat straw), while the second (T2) and third (T3) groups were fed the same diet supplemented with 3 or 6 g of YC, respectively. In the digestibility trials, results revealed that bucks fed YC had higher nutrient digestion coefficients than the control group. A similar trend was observed in feed intake. Treatment had a higher effect (P < 0.05) at 3 h post-feeding on pH for bucks fed YC than in the control group. Bucks fed YC had lower ruminal ammonia values (P < 0.05) at 3 and 6 h post-feeding than the control group. Ruminal VFA were higher (P < 0.05) for bucks fed YC at 6 h post-feeding than in the control group. The lactating Zaraibi goats had higher (P < 0.05) milk yield, and contents of milk energy, protein, total solid and solid nonfat than the control goats. It is concluded that the inclusion of 6 g per day of YC in goat's diets is recommended under field conditions. (C) 2003 Elsevier B.V. All rights reserved.