生物絮凝养殖条件下吉富罗非鱼的消化能力和非特异性免疫能力研究

为研究生物絮凝养殖条件下吉富罗非鱼的消化能力和免疫能力,采用室内循环水养殖系统(对照组)和生物絮凝养殖系统(实验组)饲养吉富罗非鱼(24.17±2.49)g 59 d。结果显示,与对照组相比,实验组水体中总氨氮(TAN)和亚硝态氮(NO-2-N)浓度均显著高于对照组,分别为(20.48±14.66)和(33.77±34.57)mg/L。但实验结束时实验组终末密度(FD)高达36.89 kg/m3,终末质量(FIW)、增重率(WGR)和特定生长率(SGR)均高于对照组(P0.05),饵料系数(FCR)比对照组降低18.7%(P0.05)。实验组饲料氮利用率为57.97%,显著高于对照组(49.51%)。实验组和对照组中罗非鱼的胃蛋白酶、胃脂肪酶、肠蛋白酶和肠脂肪酶活性无显著差异。除肝胰脏总超氧化物歧化酶(T-SOD)活性显著低于对照组外,实验组血清、肝胰脏和头肾的T-SOD、溶菌酶(LZM)、碱性磷酸酶活力(AKP)活性较对照组无差异(P0.05)。

Study of digestive activity and non-specific immunity activity of GIFT Oreochromis niloticus cultured with biofloc technology

In order to investigate the digestive activity and non-specific immunity activity of GIFT Oreochromis niloticu cultured with biofloc technology(BFT), tilapia(24.17±2.49)g]were raised in indoor recirculating aquaculture system(control group)and biofloc technology system(treatment group), respectively.During 59 days^, culturing, fluctuations of total ammonia nitrogen(TAN)and nitrite nitrogen(NO₂^--N)in the treatment group were(20.48±14.66)and(33.77±34.57)mg/L respectively, which were significantly higher than those of the control group.Final density(FD)in the treatment was as high as 36.89 kg/m³, individual weight(FIW), weight gain rate(WGR), specific growth rate(SGR)of the treatment group were significantly higher than those of the control group, and the feed conversion rate(FCR)decreased by 18.7%(P<0.05).Nitrogen utilization rate(NUR)of the treatment group was 57.79%, which was significantly higher than the control group(49.51%).Compared with the control group, activities of stomach protease, stomach lipase, intestine protease and intestine lipase of the treatment group were lightly lower, but there were no significant differences.Besides, total superoxide dismutase(T-SOD)activity in hepatopancreas of the treatment group was significantly lower than that of the control group, there were no significant differences of T-SOD, lysozyme(LZM)and alkaline phosphatase(AKP)activities in serum, hepatopancreas and head-kidney between the treatment group and the control group.