切除眼柄对日本囊对虾亲虾摄食、性腺发育及能量转化的影响

在水温(22.5±2.50)℃,盐度30～32,pH 7.8～8.3,光照1 000 lx的条件下,分别对切除眼柄和未切除眼柄的台湾海峡日本囊对虾亲虾(平均体长(19.2 ±0.95) cm,平均体质量(82.7±10.57) g)进行为期30 d的摄食、性腺发育及能量转化的初步研究.结果表明:1)实验组(切除眼柄)日本囊对虾的摄食量与摄食强度均高于对照组(未切除眼柄),夜间摄食强度分别为白天的1.39倍和1.28倍(p＜0.01);促熟期间实验组亲虾摄食量保持上升之势,而对照组为上升与下降交替出现.2)实验结束时,实验组和对照组性腺指数(GSI)的增幅分别为504.07%和91.42%(p＜0.01);性腺的干/湿质量比值(G_d/m)亦为实验组高于对照组,但二者之间差异不显著(p＞0.05).3)实验结束时,实验组和对照组亲虾的躯体能值(E_b)均略有下降,性腺能值(E_g)实验组增幅大于对照组,且两组之间差异极显著(p＜0.01),从能值的角度来看,繁殖期间的亲虾表现为负生长;实验过程中,饵料转化效率(FCE)实验组和对照组分别为10.17%和1.76%,饵料能量转化效率(ECE)分别为14.30%和2.37%,均为实验组大于对照组. 说明切除眼柄可以提高日本囊对虾亲虾的摄食量和摄食强度、促进性腺发育并提高其能量转化效率,亲虾性腺发育期间的能量除主要由食物转化之外,还消耗了机体其它组织器官的储能.由此可以了解日本囊对虾亲虾繁殖期间的摄食规律、性腺发育情况和能量转化特点并为其养殖阶段的科学管理提供理论依据.

Effects of Unilateral Eyestalk Ablation on Feeding,Gonadal Development and Energy Conversion of Marsupenaeus japonicus Broodstock

The present study was conducted to find feeding and energy conversion of Marsupenaeus japonicus broodstock from Taiwan Strait with the unilateral eyestalk ablation and the intact ones,with body length of (19.2±0.95) cm and body mass of (82.7±10.57) g/ind.The experiment lasted for 30 days in the condition of water temperature of (22.5±2.50)℃,pH 7.8～8.3,and light of 1 000 lx.The results showed as follows:1) Food intake and feeding intensity of treatment groups(with eyestalk ablation)were higher than those of control group,meanwhile ,feeding intensity at night was 1.39 times and 1.28 times higher than that in the day(p＜0.01)respectively,and the feeding intake increased in the treatment groups ,while unstable in the control groups during promoting maturity.2) Gonad indeces (GSI) between treatment groups and control groups rosed 504.07% and 91.42%,respectively,compared to the beginning (0.012 3±0.002 9),although dry/wet mass ratio(G_d/m)of treatment groups were higher than that of control groups ,there was no significant difference(p＞0.05)in the end of the experiment.3) Broodstock body energy value (E_b) of the two groups decreased slightly and the gonadal energy value of treatment groups were significant higher than that of control groups(p＜0.01).The broodstocks showed negative growth in energy.The food conversion efficiencies (FCE) (10.17%) and food energy conversion efficiency (ECE)(14.30%) of treatment groups were significantly higher than those of control groups (1.76% & 2.37 % respectively).It showed that food intake,feeding intensity of Marsupenaeus japonica could be improved,meanwhile ,the gonad development and ECE could be promoted.The energy for the gonad development was mainly from food conversion,besides ,that was also from the energy reserved in other organisms.The experiment findings can give us a clear knowledge of the law of feeding,the situation of gonadal development and characteristics of energy conversion during the breeding of Marsupenaeus japonicus broodstock,and can offer theoretical basis for scientific management of the culture procedure of Marsupenaeus japonicus broodstock.