Effects Of Microbial Enzyme On Performance, Metabolism And Immuno-function With Broilers Fed With Corn-soybean Diets

This experiment was carried out to investigate the effects of microbial enzyme on performance, metabolism and immuno?function with broilers fed with typical corn?soybean basal diets. Two hundred and eighty eight 1?day?old broilers were divided into 4 groups randomly,each containing 6 replicates and 12 chicken per replicate (6 males and 6 females): Group Ⅰ (control group), group Ⅱ (low activity of microbial enzyme), group Ⅲ (middle activity of microbial enzyme) and group Ⅳ (high activity of microbial enzyme).The results indicate that adding 0.1％ microbial enzyme to corn?soybean diets:1. Improved average daily gain (ADG), and decreased feed intake (FI) and feed /gain (F/G). Group Ⅱ,Ⅲ and Ⅳ compared with group Ⅰ,in 0～3 weeks, ADG increased by 2.94％,3.84％ (p<0.05) and 2.77％ (p<0.05) respectively；FI decreased by 3.63％ (p<0.05), 4.14％ (p<0.01) and 5.43％ (p<0.01) respectively, F/G decreased by 6.85％ (p<0.05), 8.22％ (p<0.01) and 8.22％ (p<0.01) respectively. In 4～6 weeks, ADG increased by 1.23％,2.38％ and 2.99％ respectively；FI decreased by 2.98％, 3.64％ and 5.74％(p<0.05) respectively, F/G decreased by 4.05％, 6.31％ (p<0.05) and 8.56％ (p<0.01) respectively. In 0～6 weeks, ADG increased by 1.72％, 2.82％ and 2.91％ respectively；FI decreased by 3.29％, 3.93％ and 5.85％(p<0.05) respectively, F/G decreased by 4.64％, 6.70％(p<0.05) and 8.25％(p<0.01) respectively.2．Improved the apparent metabolic rate of dry matter, energy and crude protein. Group Ⅱ,Ⅲ and Ⅳ compared with group Ⅰ, the apparent metabolic rate of dry matter increased by 0.49％, 0.56％ and 1.22％ respectively, the apparent metabolic rate of energy increased by 0.20％, 0.20％ and 1.63％ respectively, the apparent metabolic rate of crude protein increased by 2.48％, 3.51％ and 3.07％ respectively. But all differences were not significant (p>0.05). 3. Improved the index of immune organ. Group Ⅱ,Ⅲ and Ⅳ compared with group Ⅰ,on 21st day ,the weight of spleen increased by 7.59％, 8.86％ and 7.59％ respectively, the weight of thymus increased by 9.49％, 2.37％ and 14.24％ (p<0.05) respectively, the weight of fabricius bursa increased by 30.77％ (p<0.05),19.62％ (p<0.05) and 27.69％ (p<0.01) respectively；on 42nd day, the weight of spleen increased by 3.76％, 6.02％ and 12.03％ respectively, the weight of thymus increased by 23.82％ (p<0.05), 43.16％ (p<0.01) and 29.01％ (p<0.01) respectively, the weight of fabricius bursa increased by 10.93％, 15.30％ and 25.68％ (p<0.05) respectively.4. Improved the content of IgG in serum. Group Ⅱ,Ⅲ and Ⅳ compared with group Ⅰ, the content of IgG increased by 1.66％, 3.65％ and 2.33％ respectively on the 21st day, and increased by 2.32％, 10.26％ and 9.93％ respectively on the 42nd day. But differences were not significant (p>0.05).5. Improved the content of HI in blood. Group Ⅱ,Ⅲ and Ⅳ compared with group Ⅰ, the content of HI increased by 0％, 3.34％ and 2.78％ respectively on the 21st days, and increased by 0.81％, 1.77％ and 2.25％ respectively on the 42nd days. But the differences were not significant (p>0.05).6. Improved the content of TP, ALB and GLOB in serum. Group Ⅱ,Ⅲ and Ⅳ compared with group Ⅰ, on the 21st day ,the content of TP increased by 11.32％ (p<0.01),17.58％ (p<0.01) and 13.19％ (p<0.05) respectively, the content of ALB increased by 4.15％, 7.17％ and 8.30％ respectively, the content of GLOB increased by 14.11％(p<0.05) , 21.86％ (p<0.01) and 15.19％ respectively; on the 42nd day, the content of TP increased by 1.70％, 4.15％ and 3.02％ respectively, the content of ALB increased by 0.71％, 6.41％ and 3.20％ respectively, and the content of GLOB increased by 2.05％, 3.34％ and 2.95％ respectively.7. Improved the content of phosphorus and calcium in blood. Group Ⅱ,Ⅲ and Ⅳ compared with group Ⅰ, on the 21st day ,the content of phosphorus in blood increased by 4.79％, 21.81％ (p<0.05) and 7.45％ respectively, the content of calcium in blood increased by 2.43％, 7.28％ and 8.25％ (p<0.05) respectively; on the 42nd day, the content of phosphoru...