饲料中添加生长激素基因重组蛋白对斜带石斑鱼生长、消化及抗氧化能力的影响

为了探究体外表达的斜带石斑鱼生长激素基因重组蛋白在海水鱼养殖中的应用前景,将其酵母表达基因重组蛋白上清液按照2,4,8 mg/kg的添加量喷涂饲料(分组记为G1、G2和G3),与空白对照(记为G0)共4组,每组设3个平行,进行斜带石斑鱼室内工厂化养殖试验。饲养期间,早中晚各投喂1次,每日测1次水质指标,经10周的饲养,结果如下:①生长性能方面,G2组斜带石斑鱼增质量率最高,为293.16%,显著高出G0组23.75%(p0.05),饲料系数最低,为1.14,G2组斜带石斑鱼在体长增长率以及均摄食量方面显著高于G0组(p0.05);②形态学及体成分方面,G2组全鱼粗蛋白含量最高,显著高于G0组(p0.05),鱼体肌肉中粗脂肪的含量显著低于G0组(p0.05);③血脂方面,G1、G2和G3组鱼的胆固醇、低密度脂蛋白和甘油三酯含量均低于G0组,且G1和G2组的低密度脂蛋白显著低于G0组(p0.05);④消化酶活性方面,试验组斜带石斑鱼的淀粉酶活性均高于对照组,其中G2组最高,显著高于G0组(p0.05);脂肪酶活性试验组均显著高于对照组(p0.05);⑤抗氧化指标方面,试验组斜带石斑鱼肌肉总抗氧化能力显著高于G0组(p0.05);⑥磷酸酶活性方面,G2组鱼的磷酸酶活性最高,在肝脏中G2组鱼的磷酸酶活性最高且显著高于对照组(p0.05)。以上结果表明:在饲料中添加4 mg/kg的生长激素基因重组蛋白对于斜带石斑鱼的生长具有明显的促进作用且能提高饲料利用率;还可明显降低斜带石斑鱼的血脂水平,提高其消化能力和抗氧化能力。

Effects of Dietary Growth Hormone Gene Recombinant Protein on Growth,Digestion and Anti-Oxidative of Epinephelus coioides

The application prospect in sea water fish breeding influenced by the inclined Epinephelus coioides recombinant proteins was studied. The supernatant containing recombinant protein was sprayed by concentration of 2, 4, 8 milligrams per Kilogram basic orange spotted grouper diet, and the single factor experiment was composed with one control group（G0）and three treated groups（G1，G2，G3）. The fishes were raised in circulating water systems indoor and the experiment contained 3 replicates in each group. The feeding period was 10 weeks, and in this period the fishes were fed three times every day, morning, mid-noon and afternoon respectively. The water quality was monitored regularly. Results showed as follows，the G2 group possessed the highest weight gain rate for 293.16%, and  23.75% higher than control group, but its feeding rate was 1.14, which was the lowest in all groups; The length gain rate and average feeding amount of G2 group was significantly higher than that of control group (p<0.05) . The crude protein of G2 group was significantly higher than control group (p<0.05) in the fish bodies, but the muscle crude lipid was significantly lower than control (p<0.05). The treatments cholesterol, low density lipoprotein and the triglyceride in serum were decreased compared with control, and showed significant differences between G1, G2 group and G0 group (p<0.05). The amylase activity in treatments was higher than control, and the G2 group showed the significant difference (p<0.05); the lipase activity of treatments was significantly higher than control (p <0.05).The total antioxidant capacity (T-AOC) of G2 group was the highest and significantly higher than control (p<0.05); the catalase activity of G3 group was significantly higher than control (p<0.05); the treatment groups MDA content was decreased than control. The phosphates activity of G2 group was the highest in all groups and was significantly higher than control (p<0.05) in liver. The above results showed that it had an obvious promoting effect if added 4mg/kg of growth hormone gene recombinant proteins to the feed and could improve the utilization rate of feed, besides, the blood lipid level of Epinephelus coioides was reduced obviously if added appropriate growth hormone gene recombinant protein and could improve its ability to digest fat and antioxidant capacity.