饲料中添加南极磷虾粉对凡纳滨对虾亲虾生长、性腺发育及脂肪酸积累的影响

摘要

This experiment was conducted to evaluate different artificially formulated feeds on promoting gonadal development in Litopenaeus vannamei broodstock during the nutrient enrichment stage. Three kinds of formulated feeds, numbered diets no.1 (without krill meal), no.2 (10% krill meal), and no.3 (20% krill meal) were used as the experimental groups, with two replicates, and natural Nereispolychaete worm bait was used as the control group. The purpose of the experiment was to determine the appropriate formulated feed to enhance gonadal development in L. vannamei broodstock. The four treatment groups were fed the four different feeds for 60 d, and whole-body, hepatopancreatic, and gonad weights were determined. In addition, the fatty acid profiles of the four feeds and those of the hepatopancreas and gonads were analyzed in the four treatment groups. Fatty acid profiles of feed are important for gonadal development and reproduction in L. vannamei brood stock, as they can affect the hepato-pancreatic and gonadal fatty acid profiles, as well as gonadal development. Eicosapentaenoic acid (EPA) docosa-hexaenoic acid (DHA), and arachidonic acid (AA) are three kinds of polyunsaturated fatty acids (PUFAs) that play significant roles in gonadal development. T he results showed that female broodstock in the control group had the significantly highest weight gain rate, which was (78.10±6.38)% (P<0.05), compared with that of the others. No difference in weight gain rate (P>0.05) was observed between female broodstock in the three formulated feed groups. Weight gain rate of male broodstock was lower than that of females. Males in the control group had the highest weight gain rate, but no difference (P>0.05) was observed in males fed diet no. 3, and no difference (P>0.05) was observed between males fed diets no. 3 and no. 2. Fish fed diet no.2 had the lowest hepatopancreatic index at (2.37±0.02)%; the hepatopancreatic index was not different (P>0.05) from that in the control group, but was significantly different (P<0.05) from that in the other two treatment groups. Fish fed diet no. 2 had a signifi-cantly higher (P<0.05) gonadosomatic index (GSI) than that in the other groups, but no difference (P>0.05) in GSI was observed between fish fed diet no.3 and the control group. The fatty acid profiles differed among the four feeds. More ∑PUFA was detected in Nereisthan those in the artificially formulated feeds, and EPA, DHA, and AA contents in Nereiswere higher than those in the formulated feeds. Diet nos. 2 and 3 had significantly more (P>0.05)∑PUFA as well as more EPA, DHA, and AA than those in diet no.1, indicating that the fatty acid profiles in diet nos. 2 and 3 were closer to those in Nereis. These results show that the fatty acid profiles in gonads were corre-lated with the fatty acid profiles in the brood stock feeds.%为探讨人工配合饲料中添加磷虾粉对凡纳滨对虾(Litopenaeus vannamei)亲虾性腺发育的影响,分别在饲料中添加0、10%、20%的南极磷虾粉,配制3组人工配合饲料(饲料组1、饲料组2和饲料组3)对12月龄的凡纳滨对虾进行了为期60 d的营养强化培养,并以投喂双齿围沙蚕(Perinereis aibuhitensis)为对照组.营养强化结束之后,比较分析了不同饲料组凡纳滨对虾亲虾的体重增重率、肝胰腺指数(HPI)和性腺指数(GSI);另外,检测分析了各组饲料以及亲虾性腺和肝胰腺的脂肪酸组成.结果表明,对照组的雌雄亲虾体重增重率均高于3个饲料组;饲料组2的HPI最低,为(2.37±0.02)%,与对照组无显著差异(P>0.05);饲料组3的GSI与对照组无显著差异(P>0.05),但两组的GSI均低于饲料组2,并且存在显著差异(P<0.05).同时,本研究还比较分析了饲料脂肪酸组成与亲虾性腺、肝胰腺脂肪酸组成的相关性以及对亲虾性腺发育的影响.结果显示,饲料中添加一定含量(10%~20%)的南极磷虾粉可在一定程度上成为凡纳滨对虾亲虾营养强化阶段的优良饲料.