枯草芽孢杆菌对肉仔鸡生长性能、肠道形态和菌群数量的影响

本试验旨在研究枯草芽孢杆菌(Bacillus subtilis)对肉仔鸡生长性能、屠宰性能、肠道形态和菌群数量的影响。试验选取健康、体重相近的1日龄爱拔益加(AA)肉仔鸡公雏320只,随机分为4个组,每组8个重复,每个重复10只。对照组饲喂基础饲粮,试验组在基础饲粮中分别添加500 mg/kg枯草芽孢杆菌(Bacillus subtilis,BS组)、20 mg/kg硫酸黏杆菌素(colistin sulfate,CS组)和500 mg/kg枯草芽孢杆菌+10 mg/kg硫酸黏杆菌素(BS+CS组)。试验期6周。结果表明:1)与对照组相比,BS组、CS组能显著提高42日龄肉仔鸡体重(P0.05),提高后期(22~42日龄)平均日增重,显著降低后期和全期(1~42日龄)料重比(P0.05);BS+CS组未对各试验阶段肉仔鸡的生长性能产生显著影响(P0.05)。2)各试验组肉仔鸡的屠宰性能未见显著变化(P0.05)。3)与对照组相比,BS组可显著提高肉仔鸡十二指肠绒毛高度和十二指肠绒毛高度/隐窝深度(P0.05)。4)与对照组相比,BS组、CS组、BS+CS组均能显著提高肉仔鸡42日龄时盲肠乳酸杆菌数量(P0.05),BS组和BS+CS组可显著提高42日龄时盲肠中乳酸菌/大肠杆菌(P0.05)。可见,枯草芽孢杆菌可改善肉仔鸡肠道形态,增加肠道中乳酸杆菌数量,促进肉仔鸡生长。综合考虑以上因素,枯草芽孢杆菌效果优于硫酸黏杆菌素,但联合使用效果不佳。

Effects of Bacillus subtilis on Growth Performance,Intestinal Morphology and Bacterial Enumeration of Broilers

This study was conducted to investigate the effects of Bacillus subtilis on growth performance,slaughter performance,intestinal morphology and bacterial enumeration of broilers.A total of 320 one-day-old healthy male Arbor Acres broilers with similar weight were randomly allotted into 4 groups with 8 replicates per group and 10 broilers per replicate.Chickens in control group were fed a basal diet,and those in experimental groups were fed basal diets supplemented with 500 mg/kg Bacillus subtilis (BS group),20 mg/kg colistin sulfate (CS group),and 500 mg/kg Bacillus subtilis +10 mg/kg colistin sulfate (BS+CS group),respectively.The test lasted for 6 weeks.The results showed as follows:1) compared with control group,average body weight of broilers in BS and CS groups was significantly increased at 42 days of age (P＜0.05),average daily gain of broilers in BS and CS groups was increased during 22 to 42 days of age,and the ratio of feed to gain of broilers in BS and CS groups was significantly decreased during 22 to 42 days of age and 1 to 42 days of age (P＜0.05).The growth performance of broilers in BS+CS group had no significantly changes during every experimental period (P＞0.05).2) There was no significant difference in slaughter performance of broilers among all groups (P＞0.05).3) Compared with control group,the villus height and the ratio of villus height to crypt depth in duodenum of broilers in BS group were significantly increased (P＜0.05).4) Compared with control group,Lactobacillus enumeration in cecum of broilers in BS,CS and BS+CS groups was significantly increased at 42 days of age (P＜0.05).The ratio of Lactobacillus to Escherichia coli in cecum of broilers in BS and BS+CS groups was significantly increased at 42 days of age (P＜0.05).Therefore,Bacillus subtilis can improve the intestinal morphology,increase Lactobacillus enumeration in cecum and promote the growth performance of broilers.In conclusion,the effect of Bacillus subtilis is better than that of colistin sulfate,but the effect of combination of Bacillus subtilis and colistin sulfate is not good.