凝结芽孢杆菌对肉鸡生长性能、血清生化指标和胫骨强度指标的影响

本试验旨在探究凝结芽孢杆菌对肉鸡生长性能、血清生化指标及胫骨强度指标的影响。选取180只1日龄健康AA肉仔公鸡，随机分为3个处理，分别为对照组、抗生素对照组及凝结芽孢杆菌处理组。对照组饲喂基础饲粮，抗生素组在基础饲粮中添加5 mg·kg^-1黄霉素、20 mg·kg^-1吉他霉素和75 mg·kg^-1金霉素，凝结芽孢杆菌处理组在基础饲粮中添加3.6×10⁹ CFU·kg^-1的凝结芽孢杆菌，试验期为42 d。结果表明：1）饲粮中添加凝结芽孢杆菌显著降低了肉鸡前期（1~21日龄）平均日采食量（P<0.05），对平均体重和平均日增重无显著影响（P>0.05）；2）凝结芽孢杆菌处理组和抗生素组显著增加了肉鸡前期（1~21日龄）血清中总胆固醇和甘油三脂的含量（P<0.05），并显著提高了血清碱性磷酸酶的活性（P<0.05）；3）相比于对照组和抗生素组，凝结芽孢杆菌显著增加了肉鸡前期（1~21日龄）血清中总蛋白、白蛋白及球蛋白的含量（P<0.05），并显著降低了血清中尿酸和血氨的含量（P<0.05），对42日龄血清总蛋白和白蛋白含量无显著影响，但降低了血氨含量；4）饲粮中添加凝结芽孢杆菌显著提高了肉鸡前期胫骨钙含量（P<0.05），对胫骨灰分和磷含量无显著影响；凝结芽孢杆菌显著提高了42日龄肉鸡胫骨钙和磷的含量（P<0.05），其胫骨强度在三个处理组中最高，但差异未达到显著水平（P>0.05）。综上所述，肉鸡饲粮中添加凝结芽孢杆菌可在不影响肉鸡前期日增重的前提下降低平均日采食量，提高饲料转化效率，促进脂类和蛋白质在肉鸡体内的代谢与周转，并促进钙、磷在胫骨中的沉积。

Effects of Bacillus Coagulans on Growth Performance,Serum Biochemical Indices and Tibia Strength Indices of Broilers

The present study was conducted to evaluate the effects of Bacillus Coagulans on growth performance, serum biochemical and tibia indexes of broilers. One hundred and eighty 1-day-old healthy Arbor Acres broilers were randomly allotted to three treatments (basal diet; basal diet + 5 mg·kg^-1 flavomycin, 75 mg·kg^-1 aureomycin and 20 mg·kg^-1 kitasamycin; basal diet + 3.6×10⁹ CFU·kg^-1 Bacillus Coagulans). The experiment lasted for 42 days. The results showed as follows: 1) Bacillus Coagulans supplementation significantly reduced the average daily feed intake of 1-21 day broilers(P<0.05), and no significant difference in BW and ADG were observed among the treatment groups (P>0.05). 2) Compared with the control group, the supplementation of Bacillus Coagulans significantly increased the serum concentrations of triglyceride, total cholesterol and alkaline phosphatase activity of 1-21 day-old broilers (P<0.05). 3) Compared with the control group and antibiotic group, the supplementation of Bacillus Coagulans significantly increased the serum concentrations of total protein, albumin and globulin of 1-21 day broilers (P<0.05), but significantly reduced the serum ammonia and aric acid content (P<0.05), and had no significant effect on serum concentrations of total protein and albumin of day 42 broilers, but reduced the concentrations of serum ammonia. 4) The supplementation of Bacillus Coagulans significantly increased the content of calcium in the tibia of day 21 and day 42 broilers (P<0.05), and no significant difference in tibia (day 21 and 42)ash and phosphorus (day 21) content were observed among the treatment groups (P>0.05). Moreover, the tibia strength was the highest on day 42 in Bacillus Coagulans supplementation group(P>0.05). In conclusion, Bacillus Coagulans can reduce the average daily feed intake and improve the efficiency of feed conversion without decreasing the daily weight gain of broilers in the early stage. Dietary supplementation with Bacillus Coagulans supplementation is also beneficial to promote the metabolism and turnover of lipids and proteins, and improve the deposition of calcium and phosphorus in the tibia of broilers.