Chowdhury R, Islam K M S, Khan M J, Karim M R, Haque M N, Khatun M, Pesti G M
Department of Animal Nutrition, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh.
Poult Sci. 2009 Aug;88(8):1616-22. doi: 10.3382/ps.2009-00119.
The aim of this study was to determine the effect of the supplementation of an organic acid (citric acid), antibiotic growth promoter (avilamycin), and their combination for a period of 35 d on the growth, feed efficiency, carcass yield, tibia ash, and immune status of broilers. One hundred sixty 1-d-old broiler chicks (Hubbard Classic) were randomly distributed into 4 groups with 4 replicate cages having 10 birds in each. A corn-soybean-based diet was used as the basal diet (control). The basal diet was supplemented with an organic acid (citric acid, 0.5%), an antibiotic growth promoter (avilamycin, 0.001%), and their combination in other groups. The highest BW was attained in citric acid-fed chicks (1,318 g), which was significantly (P < 0.05) higher than control chicks (1,094 g) or avilamycin-fed chicks (1,217 g). The combination-fed chicks showed similar weight (1,246 g) as citric acid- or avilamycin-fed chicks (P > 0.05). Total feed intake was higher in citric acid-fed chicks compared with antibiotic-supplemented chicks. The addition of citric acid improved feed conversion efficiency (g of weight gain/ kg of feed intake) significantly (P < 0.05) compared with control chicks or its combination with avilamycin. Higher carcass weights were found in chicks fed the combination diet. Supplementation of citric acid increased tibia ash percentage significantly (P < 0.05) compared with controls. Addition of citric acid reduced the pH of the formulated diets. An improvement of immune status was detected by densely populated immunocompetent cells in the lamina propria and submucosa of cecal tonsils and ileum and also in the cortex and medulla of bursa follicles in citric acid-supplemented chicks. Supplementation of citric acid at 0.5% in the diet had positive effects on growth, feed intake, feed efficiency, carcass yield, bone ash, and immune status of broilers. Therefore, citric acid might be a useful additive instead of antibiotic growth promoters such as avilamycin, considering performance and health status of broilers.
本研究的目的是确定补充有机酸（柠檬酸）、抗生素生长促进剂（阿维拉霉素）及其组合35天对肉鸡生长、饲料效率、胴体产量、胫骨灰分和免疫状态的影响。160只1日龄的肉鸡雏鸡（哈伯德经典品种）被随机分为4组，每组有4个重复笼，每个笼中有10只鸡。以玉米-大豆为基础的日粮用作基础日粮（对照组）。在其他组中，基础日粮分别补充了有机酸（柠檬酸，0.5%）、抗生素生长促进剂（阿维拉霉素，0.001%）及其组合。饲喂柠檬酸的雏鸡体重最高（1318克），显著高于对照组雏鸡（1094克）或饲喂阿维拉霉素的雏鸡（1217克）（P<0.05）。组合饲喂的雏鸡体重（1246克）与饲喂柠檬酸或阿维拉霉素的雏鸡相似（P>0.05）。与补充抗生素的雏鸡相比，饲喂柠檬酸的雏鸡总采食量更高。与对照组雏鸡或其与阿维拉霉素的组合相比，添加柠檬酸显著提高了饲料转化效率（体重增加克数/采食量千克数）（P<0.05）。饲喂组合日粮的雏鸡胴体重量更高。与对照组相比，补充柠檬酸显著提高了胫骨灰分百分比（P<0.05）。添加柠檬酸降低了配制日粮的pH值。在补充柠檬酸的雏鸡盲肠扁桃体和回肠的固有层和黏膜下层以及法氏囊滤泡的皮质和髓质中，发现免疫活性细胞密集，表明免疫状态得到改善。日粮中添加0.5%的柠檬酸对肉鸡的生长、采食量、饲料效率、胴体产量、骨灰分和免疫状态有积极影响。因此，考虑到肉鸡的生产性能和健康状况，柠檬酸可能是一种有用的添加剂，可替代阿维拉霉素等抗生素生长促进剂。
