Ogbuewu I P, Okoro V M, Mbajiorgu C A
Department of Agriculture and Animal Health, University of South Africa, Florida Science Campus, Roodepoort, South Africa.
Department of Animal Science and Technology, Federal University of Technology, Owerri, P.M.B. 1526, Nigeria.
Trop Anim Health Prod. 2020 Jan;52(1):17-30. doi: 10.1007/s11250-019-02118-3. Epub 2019 Nov 9.
The aim of the study is to use meta-analytical procedure to resolve uncertainty, identify knowledge gaps, and create new insights using published data on the phytobiotic effect of dietary pepper intervention on daily feed intake (DFI), average daily gain (ADG), and feed conversion ratio (FCR) in broiler chickens. The authors accessed AGORA, Scopus, ScienceDirect, and Google Scholar databases for primary studies published between 2011 and 2018 using combinations of different search terms. Fifteen studies were included to assess phytobiotic effect of pepper on DFI, FCR, and ADG in broiler chickens. Random-effects model (REM) was used to generate pooled effect estimates at 95% confidence intervals (CI). Analysis was performed using Open Meta-analyst for Ecology and Evolution (OpenMEE) software, while publication bias and source of heterogeneity were assessed using standard methods. Dietary pepper supplementation enhanced ADG (standardized mean difference (SMD) = 0.576, 95% CI 0.444 to 0.707, p < 0.001) and FCR (SMD = 0.325, 95% CI - 0.453 to - 0.196, p < 0.001) considering the presence of heterogeneity and publication bias. DFI (SMD = 0.052, 95%CI - 0.069 to 0.173, p = 0.403) was not significantly influenced by dietary pepper supplementation. Restricted subgroup analysis revealed that both black and red pepper increased ADG (p < 0.001). Broilers on black pepper intervention had better FCR (p = 0.002) than broilers on red pepper treatment. Higher (p < 0.05) DFI was obtained on broilers fed pepper-based diet at the rate of > 6 g/kg feed for 35 days. There was no association between DFI and explanatory variables (broiler strain used and number of broilers used), whereas study country influenced DFI (p < 0.001). Furthermore, there was an association between outcome of interests (ADG and FCR) and explanatory variables (supplementation level, study country, number of broilers used per treatment group, and broiler strain used). Broilers on dietary pepper intervention for 42 days had higher ADG (SMD = 62.2 g/bird/day, p < 0.001) than those on dietary pepper intervention for 56 days (SMD = 35.7 g/bird/day, p = 0.002). There is evidence of heterogeneity, and meta-regression analysis showed that study country, supplementation level, and broiler strain used explained most of the sources of heterogeneity. The results of the present study revealed the potential of dietary pepper intervention to improve production efficiency in broiler chickens. The current meta-analysis also set the steps for standardized experimental designs on the use of dietary pepper intervention in broiler feeding trials in the future.
本研究的目的是使用荟萃分析程序来解决不确定性、识别知识空白，并利用已发表的关于日粮添加辣椒对肉鸡日采食量（DFI）、平均日增重（ADG）和饲料转化率（FCR）的植物源生物效应的数据来产生新的见解。作者使用不同搜索词的组合，在AGORA、Scopus、ScienceDirect和谷歌学术数据库中检索了2011年至2018年发表的原始研究。纳入了15项研究来评估辣椒对肉鸡DFI、FCR和ADG的植物源生物效应。使用随机效应模型（REM）生成95%置信区间（CI）的合并效应估计值。使用生态与进化开放荟萃分析（OpenMEE）软件进行分析，同时使用标准方法评估发表偏倚和异质性来源。考虑到异质性和发表偏倚的存在，日粮添加辣椒提高了ADG（标准化均值差（SMD）=0.576，95%CI为0.444至0.707，p<0.001）和FCR（SMD = 0.325，95%CI为-0.453至-0.196，p<0.
