投喂频率对雌雄分化后灰海马生长发育、饵料转换效率及消化酶活力的影响

以外形刚可辨别雌雄的灰海马(Hippocampus erectus)为研究对象,冰冻糠虾(Mysis spp.)为饵料,研究不同投喂频率(A:1次/d、B:2次/d、C:3次/d和D:4次/d)对雌雄分化后灰海马生长、发育、饵料转换效率及消化酶活力的影响。结果表明,整个实验期间灰海马的体质量特定生长率(WSGR)和体高特定生长率(HSGR)均随投喂频率的增加而增加,其中A、B和C3组雄海马的WSGR和HSGR均高于雌海马,而D组雌雄间差异不显著(P>0.05);随时间的推移,D组雌海马的WSGR和HSGR均呈先增后减趋势,而其它3组均呈下降趋势,且第1周的WSGR和HSGR均显著高于第5周(P<0.05)。B组灰海马的饵料转换效率(FCE)显著高于其它各组(P<0.05)。A组雌海马的性腺发育早于其它各组。A组灰海马的脂肪酶、淀粉酶和胃蛋白酶活力均显著高于其它各组(P<0.05),且该组雌海马的上述3种酶活力均显著高于雄海马(P<0.05);各组灰海马的胰蛋白酶活力相互之间差异不显著(P>0.05)。因此,在灰海马的商业养殖中应综合考虑养殖效益,根据不同发育阶段选择不同的投喂方式。而在亲体培育时,选择4次/d的投喂频率最佳。

Effects of feeding frequency on the growth, food efficiency and digestive enzyme activity of Hippocampus erectus after sex differentiation

To better understand the effects of feeding frequency on the growth,ovarian development,food efficiency and digestive enzyme activity of Hippocampus erectus after sex differentiation,four feeding frequencies(1,2,3 or 4 times per day) were applied to H.erectus in a 35-day trial.Newly sexually differentiated H.erectus were used in the experiment,which were fed with frozen Mysis spp.The results showed that the body weight specific growth rate(WSGR) and body height specific growth rate(HSGR) of the H.erectus increased with the increasing feeding frequency,and the male's were higher than the female's in all treatments.However,there were no significant differences in WSGR and HSGR between the male and the female in treatment D(4 times per day).The WSGR and HSGR decreased as the test proceeded,and the WSGR and HSGR in the fifth week were significantly higher than that in the first week(except the female's in treatment D,in which the WSGR and HSGR increased first and then deceased).The food efficiency(FCE) of the H.erectus in treatment B(2 times per day) was significantly higher than the other treatments.The ovary of the H.erectus in treatment A(1 times per day) developed earlier than the other treatments.The lipase activity,amylase activity and pepsin activity of the H.erectus in treatment A was significantly higher than the other treatments,and the female's were higher than male's in all treatments.However,the trypsin activity of the H.erectus in all treatments was not significantly different.In conclusion,the results of the current study indicated that feeding frequency for the seahorse should be adjusted based on different developmental stages for commercial seahorse production.However,it is best to choose 4 times per day on stock culturing.