Zhao Hongxia, Wang Guoxia, Wang Hairui, Mo Wenyan, Huang Yanhua, Cao Junming, Li Peijia
Institute of Animal Science, Guangdong Academy of Agricultural Sciences, Guangzhou 510640, China.
Key Laboratory of Animal Nutrition and Feed Science in South China, Ministry of Agriculture and Rural Affairs, Guangzhou 510640, China.
Anim Nutr. 2021 Jun;7(2):539-547. doi: 10.1016/j.aninu.2020.12.007. Epub 2021 Mar 30.
An 8-week feeding trial was conducted to evaluate the effects of sodium butyrate (SB) on growth, digestive enzymes, body composition and nutrient retention-related gene expression of juvenile yellow catfish (). Five isonitrogenous and isolipidic diets (420 g/kg protein and 90 g/kg lipid) were formulated to contain 0 (control), 250, 500, 1,000 or 2,000 mg/kg SB. Triplicate groups of 40 fish (BW = 1.26 ± 0.01 g) per tank (300-L cylindrical fiberglass tanks) for each diet were fed to apparent satiation twice daily. Stomach, hepatopancreas and intestine samples were obtained for digestive enzymes activities analyses. A real-time quantitative PCR analysis was performed to determine the relative expression of target of rapamycin () and lipoprotein lipase () in the hepatopancreas and intestine. Fish fed the diets supplemented with SB at 500 and 1,000 mg/kg showed significantly higher specific growth rate and significantly lower feed conversion ratio compared to the control ( < 0.05). Dietary SB inclusion did not alter activities of intestinal amylase, creatine kinase and sodium-potassium adenosine triphosphatase (Na/K-ATPase), but increased activities of hepatic trypsin, stomachic lipase, intestinal lipase, alkaline phosphatase and γ-glutamyl transpeptidase for fish fed 1,000 mg/kg SB compared to the control ( < 0.05). Intestine length index, intestine somatic index, fold height and muscular thickness of distal intestine were significantly higher in 1,000 mg/kg SB groups compared to the control ( < 0.05). Significantly higher levels of whole-body crude protein, ash, calcium, phosphorus, nutrition retention and relative mRNA of intestinal were observed in 1,000 mg/kg SB group ( < 0.05). Whole-body lipid content and hepatopancreas mRNA expression in 2,000 mg/kg SB group were significantly higher than the control ( < 0.05). Relative mRNA levels of intestinal and hepatopancreas were significantly higher in the 500 mg/kg SB group compared to those in other groups ( < 0.05). The increased growth performance, digestive enzymes and nutrient retention in fish fed the diets supplemented with SB at 500 and 1,000 mg/kg suggests that SB can be a desirable growth promoter as an antibiotic alternative in diets.
进行了一项为期8周的饲养试验，以评估丁酸钠（SB）对幼龄黄颡鱼生长、消化酶、体成分及营养保留相关基因表达的影响。配制了五种等氮等脂日粮（蛋白质含量420 g/kg，脂肪含量90 g/kg），分别含有0（对照）、250、500、1000或2000 mg/kg的SB。每种日粮设置三个重复组，每组40尾鱼（体重=1.26±0.01 g），饲养于每个300升圆柱形玻璃纤维水箱中，每天投喂两次，直至明显饱足。采集胃、肝胰腺和肠道样本进行消化酶活性分析。采用实时定量PCR分析测定肝胰腺和肠道中雷帕霉素靶蛋白（）和脂蛋白脂肪酶（）的相对表达。与对照组相比，饲喂添加500和1000 mg/kg SB日粮的鱼体特定生长率显著更高，饲料转化率显著更低（<0.05）。日粮中添加SB并未改变肠道淀粉酶、肌酸激酶和钠钾三磷酸腺苷酶（Na/K-ATPase）的活性，但与对照组相比，饲喂1000 mg/kg SB的鱼肝脏胰蛋白酶、胃脂肪酶、肠道脂肪酶、碱性磷酸酶和γ-谷氨酰转肽酶的活性增加（<0.05）。与对照组相比，1000 mg/kg SB组的肠长指数、肠体指数、远端肠皱襞高度和肌层厚度显著更高（<0.05）。1000 mg/kg SB组的鱼体粗蛋白、灰分、钙、磷、营养保留率及肠道相对mRNA水平显著更高（<0.05）。2000 mg/kg SB组的鱼体脂肪含量和肝胰腺mRNA表达显著高于对照组（<0.05）。与其他组相比，500 mg/kg SB组的肠道和肝胰腺相对mRNA水平显著更高（<0.05）。饲喂添加500和1000 mg/kg SB日粮的鱼生长性能、消化酶和营养保留率增加，表明SB可作为日粮中抗生素的理想替代生长促进剂。
