PDF(Pubmed)
Abstract：
Eimeria infections impair digestive tract capacity and barrier function leading to poor growth and feed efficiency. A meta-analysis approach was used to evaluate and quantify impact of Eimeria infection on the apparent ileal digestibility (AID) of amino acids (AA) in broiler chickens. A database composed of 6 articles with a total of 21 experiments was built for the effect of challenge type (a mix of Eimeria spp. vs. E. acervulina) and subdatabase of 3 articles with a total of 15 experiments for the effect of E. acervulina dose response. Regression models were fitted with the mixed model procedure in Minitab 19 with fixed effects of challenge, species, and their interactions. For the sub database, the mixed model procedure was used to fit regression models and identify a linear or quadratic response to dose. Challenge decreased AID (P < 0.05) of both dispensable and indispensable AA except for Trp. Specifically, the largest depression was observed for Cys, Thr, Tyr, Ala, and Val with the magnitude of difference of 8.7, 5.4, 5.2, 5.1, and 4.9%, respectively for challenged vs. unchallenged birds. The type of challenge affected (P < 0.05) AID of AA with exception of Cys, Tyr, Ala, Ser, Leu, Asp, Gly, and Pro. E. acervulina challenge had larger negative effects on AID of Ile, Leu, and Val. Moreover, E. acervulina linearly decreased (P < 0.05) AID of all indispensable and dispensable AA except for Trp and quadratically (P < 0.05) decreased AID of all AA except Cys, Met, Arg, and Trp. The largest linear decrease due to E. acervulina dose was seen for AID of Cys, followed by Ala, Val, Thr, and Ile. Although, AID of Trp was not affected by E. acervulina challenge, mixed Eimeria species challenge decreased (P < 0.05) AID of Trp. Overall, the results confirmed that an Eimeria infection negatively impacted AA digestibility/utilization. The ranking of the most affected AA suggested ground for nutritional intervention during subclinical field Eimeria infections or vaccination programs.
摘要：
艾美球虫感染会损害消化道容量和屏障功能，导致生长和饲料效率低下。使用荟萃分析方法来评估和量化艾美球虫感染对肉鸡氨基酸（AA）的表观回肠消化率（AID）的影响。建立了一个由6篇文章组成的数据库，总共21个实验，以研究挑战类型的影响（艾美球虫属的混合物。vs.E.acervulina）和3篇文章的子数据库，共15个实验，用于研究E.acervulina剂量反应的效果。回归模型与Minitab19中的混合模型程序拟合，具有固定的挑战效应，物种,和他们的互动。对于子数据库，混合模型程序用于拟合回归模型,并确定对剂量的线性或二次反应.除Trp外，挑战降低了可有可无和不可缺少的AA的AID（P<0.05）。具体来说,最大的抑郁症是Cys，Thr,Tyr,阿拉,和Val的差异幅度分别为8.7、5.4、5.2、5.1和4.9%，分别为被挑战的vs.没有挑战的鸟除Cys外，攻击类型影响AA的AID（P<0.05），Tyr,阿拉,Ser,Leu,Asp,Gly,和Pro。E.acervulina攻击对Ile的AID有更大的负面影响，Leu,还有Val.此外，除Trp外，所有必需和可有可无的AA的AID呈线性下降（P<0.05），除Cys外，所有AA的AID呈二次下降（P<0.05）。Met,Arg,Trp。对于Cys的AID，观察到由于E.acervulina剂量引起的最大线性下降，其次是Ala,Val,Thr,还有Ile.虽然,Trp的AID没有受到E.acervulina攻击的影响，混合艾美球虫物种攻击降低了Trp的AID（P<0.05）。总的来说,结果证实，艾美球虫感染对AA的消化率/利用率产生负面影响。受影响最大的AA的排名表明，在亚临床现场艾美球虫感染或疫苗接种计划期间进行营养干预的基础。
