摘要：The increase in bio-ethanol industry has created a need for alternative to corn for ruminants. In the other side there is increase in availability of glycerol, a primary co-product material of biodiesel production. The objective of this study was to investigate the effect of partial replacing of corn with glycerol in diets fed to lactating goats. Twelve lactating Nubian goats were fed a base diet (T1), diets containing 9% glycerol (on DM basis) (T2) and diet containing 9% glycerol plus commercial enzymes 4 g kg-1 DM (on DM basis) (T3) for 84 days. The experimental diets T2 and T3 decreased butyric acids concentration and acetate:propionate ratio in rumen liquor in relation to T1, the concentration of propionic acid was increased in T2 and T3 compared with T1. Replacing corn by glycerol (T2) decreased apparent nutrients digestion coefficients Dry Matter (DM), Organic Matter (OM), Crud Protein (CP), Neutral Detergent Fiber (NDF) and Acid Detergent Fiber (ADF) comparing with other treatments (T1 and T3). Milk production was 1581, 1174 and 1610±77.6 g h-1 day-1 and FCM was 1774, 1030 and 1648±115.9 g h-1 day-1 for T1, T2 and T3, respectively, Milk composition was not altered by glycerol feeding plus fibrinolytic enzymes (T3) except that milk total protein was decreased from 4.6 24 to 3.5%. While, replacing corn by glycerol (T2) decreased values of milk composition compared with control diets (T1). The results indicated that glycerol is a suitable replacement for corn grain with adding fibrinolytic enzymes in diets for lactating goats and that it may be included in rations to a level of at least 9% of dry matter without adverse effects on milk yield or milk composition.
