不同开口饵料对西杂鲟(西伯利亚鲟♀×史氏鲟♂)仔鱼生长和成活的影响

Effect of initial feeding on the growth and survival of larvae Acipenser baerii♀×Acipenser schrenckii♂

试验研究不同开口饵料对西杂鲟生长和成活率的影响。初重(0.0344±0.0018)g的西杂鲟(Acipenser baerii♀×Acipenser schrenckii♂)开口仔鱼,分为8组,分别饲喂水蚯蚓、蚯蚓、蚕蛹粉、水蚯蚓+蚯蚓粉、水蚯蚓粉、枝角类粉、蚯蚓粉和磷虾粉8种饵料或饵料组合。试验期28d。结果显示,仔鱼的末重、终末体长、增重率、特定生长率为水蚯蚓>蚯蚓>蚕蛹粉>水蚯蚓+蚯蚓>水蚯蚓粉>枝角类粉>蚯蚓粉>磷虾粉。仔鱼的成活率为水蚯蚓>蚯蚓>水蚯蚓+蚯蚓>蚕蛹粉>水蚯蚓粉>枝角类粉>蚯蚓粉>磷虾粉。试验表明,西杂鲟开口仔鱼投喂鲜活水蚯蚓、鲜活蚯蚓优于干粉生物饵料。在生物饵料缺乏情况下,投喂蚕蛹粉可在一定程度上替代生物饵料,促进西杂鲟仔鱼的生长和成活。在开口仔鱼培育阶段,水体中是否存在丰富的适口饵料,是决定鱼苗存活的关键。西杂鲟仔鱼容易在开口10-19 d后迎来饥饿不可逆点。

The aim of the experiment was to study the effect of initial feeding on the growth and survival of larvae Acipenser baerii♀× Acipenser schrenckii♂.Larvae Acipenser baerii♀×Acipenser schrenckii♂ with average body weight of(0.0344±0.0018)g were divided into eight group and were fed with tubificidae,earthworms,silkworm pupa powder,tubificidae+earthworms powder,tubificidae powder,cladocerans powder,earthworms powder and euphausiid shrimp powder for 28 d.The results showed that final body weight(FBW),final total length(FTL),weight gain rate(WGR)and specific growth rate(SGR)were tubificidae>earthworms>silkworm pupa powder>tubificidae+earthworms powder>tubificidae powder>cladocerans powder>earthworms powder>euphausiid shrimp powder.Survival rate of larvae were tubificidae>earthworms>tubificidae+earthworms powder>silkworm pupa powder>tubificidae powder>cladocerans powder>earthworms powder>euphausiid shrimp powder.The experiment indicates that fresh tubificidae and earthworms were better than powder.In case of lack of biological food,silkworm pupa powder can replace biological food to a certain extent to promote the growth and survival of larvae.On the initial feeding stage,whether there is abundant palatable food in the water is the key factor to determine the survival of larvae.The larvae are easy to face the irreversible point of starvation after 10-19 d.