Nikoofard V, Mahdavi A H, Samie A H, Jahanian E
Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, Isfahan, Iran.
J Anim Physiol Anim Nutr (Berl). 2016 Feb;100(1):189-99. doi: 10.1111/jpn.12316. Epub 2015 Mar 21.
As alterations of dietary electrolyte balance (DEB) can influence amino acid metabolism via changes the ions incur in their configurations, performance and immunological responses of broiler chicks might be affected. So, the current study was carried out to investigate the effects of different levels of sulphur amino acids (SAA) and DEB on performance, jejunal morphology and immunocompetence of broiler chicks. A total of 360 1-day-old male Ross 308 broiler chicks were randomly assigned to nine experimental treatments with four replicates of 10 birds each. Experimental treatments consisted of three levels of SAA (100, 110, and 120% of NRC recommendation, provided by methionine supplementation in diets with the same cysteine level) and three levels of DEB (150, 250, and 350 mEq/kg) that were fed during the entire of trial in a 3 × 3 factorial arrangement. Results showed that the relative weights of intestine and abdominal fat were decreased markedly (p < 0.001) with increasing levels of SAA and DEB respectively. Antibody titre against sheep red blood cell was neither individually nor in combination influenced by supplementation of SAA or DEB. Nevertheless, a decrease in DEB level led to a suppression in heterophile (p < 0.05) and an increase in lymphocyte counts (p = 0.06); consequently, heterophile to lymphocyte ratio was significantly decreased (p < 0.05) by decremental levels of DEB. Albumin to globulin ratio was increased after inclusion of at least 10% SAA (p < 0.001) and 150 mEq DEB/kg in the diet (p = 0.11). Although feeding high-DEB level led to a remarkable decrease in villus height (p < 0.01) and goblet cell numbers (p < 0.001), supplementing the highest level of SAA improved the height of jejunal villus. During the entire trial period, average daily feed intake (ADFI) was increased by incremental SAA levels (p < 0.05). However, inclusion of 150 mEq/kg led to not only a remarkable increase (p < 0.0001) in both ADFI and average daily weight gain (ADWG) but also to improved (p < 0.001) feed conversion ratio (FCR) both during the growing and over the entire trial periods. The present findings indicated that inclusion of low DEB decreased the heterophile to lymphocyte ratio and improved both the albumin to globulin ratio and intestinal health indices. The best growth performance was obtained with 150 mEq DEB/kg in the diet for each level of SAA.
由于膳食电解质平衡（DEB）的改变可通过改变离子的构型来影响氨基酸代谢，肉仔鸡的生产性能、免疫反应可能会受到影响。因此，本研究旨在探讨不同水平的含硫氨基酸（SAA）和DEB对肉仔鸡生产性能、空肠形态及免疫能力的影响。选取360只1日龄雄性罗斯308肉仔鸡，随机分为9个试验处理组，每组4个重复，每个重复10只鸡。试验处理包括3个SAA水平（分别为NRC推荐量的100%、110%和120%，通过在半胱氨酸水平相同的日粮中添加蛋氨酸来提供）和3个DEB水平（150、250和350 mEq/kg），在整个试验期采用3×3析因设计进行饲喂。结果表明，随着SAA和DEB水平的升高，肠道和腹脂相对重量分别显著降低（p<0.001）。SAA或DEB的添加，无论是单独添加还是联合添加，均不影响抗绵羊红细胞抗体效价。然而，DEB水平的降低导致异嗜性粒细胞数量减少（p<0.05），淋巴细胞数量增加（p=0.06）；因此，随着DEB水平的降低，异嗜性粒细胞与淋巴细胞比值显著降低（p<0.05）。日粮中至少添加10%的SAA（p<0.001）和150 mEq DEB/kg（p=0.11）后，白蛋白与球蛋白比值升高。尽管高DEB水平日粮导致绒毛高度（p<0.01）和杯状细胞数量显著减少（p<0.001），但添加最高水平的SAA可改善空肠绒毛高度。在整个试验期内，随着SAA水平的升高，平均日采食量（ADFI）增加（p<0.05）。然而，添加150 mEq/kg不仅使生长阶段和整个试验期的ADFI和平均日增重（ADWG）显著增加（p<0.0001），而且使饲料转化率（FCR）得到改善（p<0.001）。本研究结果表明，低DEB日粮可降低异嗜性粒细胞与淋巴细胞比值，提高白蛋白与球蛋白比值及肠道健康指标。对于每个SAA水平，日粮中添加150 mEq DEB/kg时肉仔鸡生长性能最佳。
