二甲基-β-丙酸噻亭对哲罗鱼生长性能和蛋白质代谢的影响

摘要

We evaluated the effects of dimethyl-β-propiothetin (DMPT) on growth, proximate muscle composition, and protein metabolism in Hucho taimen. Juvenile fish (n=1 800, average initial body weight:4.20±0.02 g) were cultured in a flow through system. The fish were randomly divided into six triplicate groups of 100 fish and fed diets containing different levels of DMPT (0, 0.25%, 0.5%, 0.75%, and 1.0%) for 56 d. Weight gain rate was highest at 0.2%DMPT supplementation (P<0.05). The optimum supplementation was 0.24% based on a polynomial regression analysis be-tween dietary DMPT level and weight gain rate. Serum total protein, albumin, and globulin increased significantly with 0.05% DMPT supplementation (P<0.05) and serum total protein, globulin and serum aspartate aminotransferase in-creased significantly with 0.2%DMPT supplementation (P<0.05). Meanwhile, liver and muscle protein levels and pro-tease activity in the digestive track increased significantly as dietary DMPT supplementation increased between 0.02%and 0.5%(P<0.05). The liver somatic index increased significantly with 0.05%DMPT supplementation. DMPT sup-plementation had no effect on muscle crude lipid, ash, amino acid profile, or serum alanine transaminase (P>0.05). Our results suggest that growth performance and protein levels were improved by dietary DMPT supplementation in taimen and 0.02%-0.5%DMPT supplementation can increase the protein storage in muscle and liver.%本研究旨在探讨二甲基-β-丙酸噻亭(DMPT)对哲罗鱼(Hucho taimen)生长性能、肌肉成分和蛋白质代谢的影响。选取1800尾初始体质量为(4.20±0.02) g的健康幼鱼,随机分为6组,设1个对照组,5个处理组,每组3个重复,每重复100尾。各处理组分别在基础饲料中添加0.02%、0.05%、0.1%、0.2%和0.5%的DMPT,对照组投喂基础饲料。室内流水饲养周期为56 d。结果表明,饲料中DMPT添加量为0.2%时,哲罗鱼增重率和摄食率达最大值；以DMPT添加量和增重率进行二次曲线回归分析,得出DMPT最适添加量为0.24%。DMPT添加量为0.05%时,血清总蛋白、白蛋白和球蛋白水平显著提高(P<0.05)；添加0.2%DMPT时,血清总蛋白、球蛋白水平和谷草转氨酶水平显著提高(P<0.05)；添加水平0.02%~0.5%时,哲罗鱼肝和肌肉蛋白质水平显著升高(P<0.05),胃、肠道蛋白酶活性显著升高(P<0.05)；添加水平0.05%时,脏体指数显著降低(P<0.05)；各处理组肌肉脂肪和灰分含量均与对照组差异不显著(P>0.05),各组间血清谷丙转氨酶、肌肉氨基酸组成及含量未呈显著差异(P>0.05)。综上可见,饲料中添加0.2%DMPT可明显提高哲罗鱼生长性能,添加0.02%~0.5%DMPT可增加哲罗鱼肌肉和肝蛋白储存。