摘要
【目的】利用荟萃分析(Meta分析)研究日粮中添加乳酸杆菌对肉鸡生长性能的影响,以期为肉鸡生产提供一定的理论和数据参考。【方法】从国内外数据库中共检索出符合分析要求的24篇文献,包括25项试验,8 702个研究对象。采用Review Manager(version 5.3),计算各生长性能指标的标准化均数差SMD(乳酸杆菌组和对照组均数的差值除以两组标准差平均值的商),根据不同研究使用的样本数量、指标测定的标准差,确定不同研究结果的权重值,汇总多个相互独立的研究结果。根据I2统计量对纳入文献的生长性能数据进行异质性检验,通过漏斗图及egger检验分析纳入文章的发表偏倚并进行敏感性分析。由于本次分析各项指标均存在显著异质性,故采用随机效应模型对连续型数据进行分析,并根据乳酸杆菌菌种进行亚组分析,探讨不同乳酸杆菌对肉鸡生长性能的影响效果。【结果】从试验全期来看,饲粮中添加乳酸杆菌显著提高肉鸡的平均日增重(SMD=1.53,P<0.001),显著降低料重比(SMD=-1.50,P<0.001),对采食量无显著影响(P=0.470)。分别分析肉鸡前期(1-21日龄)和后期(22-42日龄)的生长数据发现,乳酸杆菌显著提高肉鸡前期平均日增重(SMD=1.05,P<0.001),有提高后期日增重的趋势(SMD=0.52,P=0.090),显著降低前期料重比(SMD=-1.31,P<0.001)和后期料重比(SMD=-0.94,P<0.001)。从SMD的数值上可以看出,乳酸杆菌对肉鸡前期的促生长效果优于后期。漏斗图及egger分析表明,前期F/G(P=0.012)和后期ADFI(P=0.006)偏倚性达到显著水平,其他指标的偏倚性不显著(P>0.05);敏感性分析发现,日增重和料重比的分析结果稳定。异质性检验发现,各生长指标存在显著异质性(P<0.001),根据乳酸杆菌菌种进行亚组分析,可降低Meta分析结果的异质性。亚组分析显示,植物乳酸杆菌对肉鸡全期日增重(1.98,P<0.001)和饲料转化效率(-1.66,P<0.001)的促进作用优于干酪乳杆菌(0.51,-0.68,P≤0.02)和约氏乳杆菌(1.15,-0.16,P≤0.02)。【结论】Meta分析表明,乳酸杆菌可改善不同阶段肉鸡的日增重和饲料转化效率,对采食量无显著影响。不同乳酸杆菌的促进作用存在差异,其中植物乳杆菌的促进作用最优。
【Objective】The purpose of present study was to analyze the effects of Lactobacillus supplements on the growth performance of broilers by meta-analysis. 【Method】A total of 24 articles, including 25 trials and 8 702 subjects, were retrieved from domestic and foreign databases. Reviewing Manager(version 5.3) was used to calculate the standardized mean difference(SMD)(the difference between Lactobacillus group and control group divided by the mean of standard deviation between the two groups). According to the number of samples used in different studies and the standard deviation determined by the indicators, the weights of different research results were determined, and several independent research results were summarized. According to I2 statistics, the heterogeneity of growth performance data was tested, and the publication bias was analyzed by funnel plot and egger test. The random effect model was used to analyze the continuous data for the significant heterogeneity of each index in this analysis and subgroup analysis was carried out according to Lactobacillus strains to explore the effects of different Lactobacillus on the growth performance of broilers.【Result】The analysis showed that Lactobacillus significantly increased the ADG(SMD=1.53, P<0.001) and reduced the F/G(SMD=-1.50, P<0.001) of broilers during 0-6 week period of the experiment, and had no significant effect on feed intake(P=0.470). Lactobacillus significantly increased the ADG of broilers(SMD=1.05, P<0.001) in the growing period, and had a tendency to improve ADG(SMD=0.52, P=0.090) in the finishing period, significantly reduced the growing F/G(SMD=-1.31, P<0.001) and the finishing F/G(SMD=-0.94, P<0.001). The growth-promoting effect of Lactobacillus on broilers was better than that the finishing period according to the value of SMD. Funnel plot and egger analysis showed that the bias of F/G(P=0.012) and ADFI(P=0.006) in the early stage reached a significant level, while the biases of other indicators were not significant(P>0.05). Sensitivity analysis found that random deletion of arbitrary literature data had little effect on the analysis of daily gain and feed-to-weight ratio, indicating that the above results were stable and were not affected by one or several articles. The heterogeneity test found that there was significant heterogeneity in the analysis results of each growth index(P<0.001), indicating that the results of different literatures differed greatly, possibly due to differences in the Lactobacillus species or feeding doses used in different studies. Subgroup analysis based on Lactobacillus species could reduce the heterogeneity of the meta-analysis. Subgroup analysis showed that L. plantarum promoted the daily weight gain(1.98, P<0.001) and feed conversion efficiency(-1.66, P<0.001) on broiler 0-6 week period better than L. casei(0.51,-0.68, P≤0.02) and L. johnsonii(1.15,-0.16, P≤0.02). 【Conclusion】In conclusion, the meta-analysis showed that Lactobacillus could increase the daily weight gain and feed conversion efficiency of broilers at different period, and had no significant effect on feed intake. The promotion effect of Lactobacillus was different, among which L. plantarum was better.
作者
邢爽
冯京海
XING Shuang;FENG JingHai(Institute of Animal Science,Chinese Academy of Agricultural Sciences/State Key Laboratory of Animal Nutrition,Beijing 100193)
出处
《中国农业科学》
CAS
CSCD
北大核心
2020年第1期183-190,共8页
Scientia Agricultura Sinica
基金
国家重点研究发展计划(2016YFD0500509)
中国农业科学院科技创新工程(ASTIP-IAS09)