1.Wuxi Fisheries College,Nanjing Agricultural University,Wuxi 214081,China;2.Sino-US Cooperative Laboratory for Germplasm Conservation and Utilization of Freshwater Mollusks,Freshwater Fisheries Research Center,Chinese Academy of Fishery Sciences,Wuxi 214081,China;3.Key Laboratory of Genetic Breeding and Aquaculture Biology of Freshwater Fishes,Ministry of Agriculture,Freshwater Fisheries Research Center,Chinese Academy of Fishery Sciences,Wuxi 214081,China
Abstract: Two feeding trails were conducted to study effects of different diets and sediments on growth of juvenile freshwater mussel Hyriopsis cumingii at water temperature of(24±1)℃in order to find suitable diets and sediment for survival of freshwater mussel juveniles.In the first trail,effects of two different substrates(fine sediment and fine sediment with calcium powder)and two diets(Nanno 3600 and Shellfish diet 1800)on survival and growth of 1-30 d old freshwater mussel juveniles(freshly metamorphosed)were tested,and in the second trail,influences of five diets(Nanno 3600,Shellfish diet 1800,Chlorella vulgaris,Scenedesmus quadricauda and Oocystis sp.)on survival and growth of 31-60 d old juveniles were studied.The one-way analysis of variance revealed that there was no significant difference in survival between the juveniles in group A3 fed Nanno 3600 and fine sediment(P＞0.05)and in group A1 fed mixed algae and fine sediment,significant difference(P＜0.05)that in the juveniles fed mixed algae in group A2 and fine sediment with calcium,and very significant difference(P＜0.01)with group A5 which was cultured in pond water collected from the Freshwater Fisheries Research Center.The best growth was observed in the juveniles in group A2,with far higher shell length than those in groups A1 and A3(P＜0.05)and very far higher than those in groups A4 and A5(P＜0.01).In the second stage,group B5 presented significantly higher survival rate compared to groups B1,B2 and B4(Shellfish diet 1800)(P＜0.05),and very significantly higher survival rate compared to group B3(P＜0.01).There was no significant difference in shell length between group B5 and groups B4(P＞0.05),significance difference in groups B1 and B2(P＜0.05),and very significant difference with group B3(P＜0.01).It can be concluded that the survival will be improved in 1-30 d old juveniles fed Nannochloropsis oculata in Nanno 3600,and that adding calcium in sediment is conducive to the growth of the juveniles.Nannochloropsis oculata is more conducive to growth of the 31-60 d old juvenile freshwater mussel.
2017, Vol. 32 
