摘要：This study evaluated the effect of varied levels of probiotc ( Saccharomyces cereviae ) on total serum and egg cholesterol levels in laying birds. The impact of this probiotic on hen-day egg performance was also studied. A total of 100 layers were randomly divided into 4 groups (A, B, C and D) of 25 layers each. The diets for groups A, B and C were supplemented with probiotic at varied levels of 0.6, 0.8 and 1.0 g/kg of feed, respectively. Group D diet had no probiotic (Control). The layers were given 120 g of feed per bird per day in two divided doses (morning and afternoon). Eggs were collected three times daily (morning, afternoon and evening). All the eggs collected from each group were weighed and recorded daily. Five birds were randomly selected from each group and 5.0 ml of blood was collected from each bird. The blood samples were allowed to clot in a sample bottle and serum harvested was used to determine the total serum cholesterol content with the aid of a commercial kit. Five eggs were also randomly collected from each group and used to determine the total egg cholesterol content following standard procedure. The result showed that the probiotic fed groups had a significant (p < 0.05) reduction in serum cholesterol levels than the control (group D). The least mean serum cholesterol level was group A (108.33±9.28 mg/dl) followed by group C (112.67±7.88 mg/dl) and group B (115.00±14.34 mg/dl). Group D (control) had a significantly higher mean serum cholesterol level of 166.67±8.82 mg/dl. Group C had a significantly higher (p < 0.05) hen-day egg performance of 85.00±10.00%, followed by group B with 70.00±9.35% hen-day egg performance. Group A had a hen-day egg performance of 68.00±8.93% while group D (the control) had the least hen-day egg performance of 65.00±5.00%. Probiotic inclusion of 1.0 g/kg of feed was therefore recommended for effective reduction in serum and egg cholesterol levels and optimum hen-day egg performance.
