抗菌肽对凡纳滨对虾生长和血清非特异性免疫指标的影响

为考察抗菌肽对凡纳滨对虾(Litopenaeus vannamei)生长、饲料利用和免疫能力的影响,分别在基础组饲料中添加0 mg/kg(对照组)、300 mg/kg、400 mg/kg和500 mg/kg抗菌肽,投喂平均体重为(0.8±0.1 g)的凡纳滨对虾6周。结果表明,饲料中添加抗菌肽后,凡纳滨对虾的成活率均显著高于对照组(P<0.05);300 mg/kg抗菌肽组的增重率和饲料系数分别为509.10%、1.33,较对照组提高增重率8.76%(P<0.05),降低饲料系数12.5%(P<0.05),而添加400 mg/kg、500 mg/kg抗菌肽对增重率、饲料系数无显著影响,但显著提高了肌肉粗脂肪含量,各处理组在肌肉粗蛋白、水分含量上无显著差异;300 mg/kg、400 mg/kg抗菌肽组的血清碱性磷酸酶、超氧化物歧化酶、谷丙转氨酶、谷草转氨酶及400 mg/kg抗菌肽组的溶菌酶均显著高于对照组。上述研究表明,饲料中添加300 mg/kg抗菌肽,可显著提高凡纳滨对虾成活率和增重率,降低饲料系数;添加400 mg/kg抗菌肽,对血清非特异性免疫指标有提高作用,凡纳滨对虾饲料中抗菌肽的添加量建议为300～400 mg/kg。

Effect of antibacterial peptide on growth and serum non-specific immunity of Litopenaeus vannamei

The present study was conducted to evaluate the effect of dietary antibacterial peptide on growth,feed utilization and immunity of Litopenaeus vannamei.Four diets were formulated with adding 0 mg/kg(control group),300 mg/kg,400 mg/kg,500 mg/kg antibacterial peptide in basal diet.L.vannamei with initial body weight of 0.8±0.1 g were fed the four diets for 6 weeks.Results indicated that the survival rates of the three antibacterial peptide addition groups were significantly higher than that of control group(P<0.05),WGR and FCR in the group of 300mg/kg antibacterial peptide was 509.10%,1.33,respectively,8.76% higher and 12.5% lower than those of control group(P<0.05).Adding 400 mg/kg,500 mg/kg antibacterial peptide in diet had no significant effects on WGR and FCR,but increased lipid contents in muscle.There were no significant difference in crude protein,water content among all groups.Serum AKP,SOD,ALT,AST of 300 mg/kg,400 mg/kg groups and LSZ of 400 mg/kg group were significantly higher than those of control group(P<0.05).Results above showed that adding 300 mg/kg antibacterial peptide in diet could improve survival rate,WGR and decrease FCR,and adding 400 mg/kg antibacterial peptide could improve the serum nonspecific immunity indexes.The addition of antibacterial peptide was suggested to be 300~400 mg/kg in diet for L.vannamei.