不同饵料对大鲵稚体生长性能、体组成和消化酶活性的影响

为确定大鲵稚体的最佳饵料,本试验研究了不同饵料对大鲵稚体生长性能、体组成和消化酶活性的影响。试验选取平均体重为(1.08±0.01)g的大鲵稚体300尾,随机分成5组,每组3个重复,每个重复20尾。5组大鲵稚体投喂5种不同的饵料,分别为鱼块、黄粉虫、水蚯蚓、卤虫和米虾,养殖时间为60 d。结果显示:不同饵料对大鲵稚体的存活率以及全鱼水分、粗灰分含量均无显著影响(P0.05);米虾组的末均重、增重率和特定生长率均为各组最高,显著高于水蚯蚓组和卤虫组(P0.05);黄粉虫组和水蚯蚓组的肥满度显著高于卤虫组(P0.05)。干物质效率表现为鱼块组和水蚯蚓组显著高于其他各组(P0.05),米虾组显著高于卤虫组和黄粉虫组(P0.05),卤虫组显著高于黄粉虫组(P0.05);各组间大鲵稚体蛋白质效率差异显著(P0.05),表现为水蚯蚓组米虾组鱼块组卤虫组黄粉虫组;鱼块组脂肪效率显著高于其他组(P0.05),卤虫组和米虾组显著高于水蚯蚓组和黄粉虫组(P0.05),水蚯蚓组显著高于黄粉虫组(P0.05)。米虾组全鱼粗蛋白质含量为各组最高,显著高于黄粉虫组和卤虫组(P0.05);而全鱼粗脂肪含量最高的是黄粉虫组,显著高于其他各组(P0.05)。各组大鲵稚体全鱼17种氨基酸含量、氨基酸总量、必需氨基酸总量和鲜味氨基酸总量差异不显著(P0.05),但水蚯蚓组、卤虫组和米虾组的必需氨基酸与非必需氨基酸的比值显著高于鱼块组和黄粉虫组(P0.05)。鱼块组和米虾组大鲵稚体胃肠道蛋白酶活性显著高于黄粉虫组和卤虫组(P0.05);黄粉虫组胃肠道脂肪酶活性显著高于其他各组(P0.05);胃肠道淀粉酶活性仅卤虫组显著低于其他各组(P0.05)。综上所述,米虾是大鲵稚体的最佳饵料,鱼块次之,水蚯蚓和黄粉虫最后选用。

Effects of Different Diets on Growth Performance,Body Composition and Digestive Enzyme Activities of Juvenile Chinese Giant Salamander ( Andrias davidiaus)

In order to determine the optimal diet, this experiment was conducted to investigate the effects of different diets on growth performance, body composition and digestive enzyme activities of juvenile Chinese gi?ant salamander ( Andrias davidiaus) . A total of 300 juvenile Chinese giant salamander with the average body weight of (1.08±0.01) g were randomly divided into 5 groups with 3 replicates per group and 20 fish per rep?licate. Fish in the 5 groups were fed 5 different diets for 60 d, and the diets were raw fish block, Tenebrio molitor L., tubifex, brine shrimp and caridina, respectively. The results showed that no significant differences in survival rate ( SR) , and the contents of moisture and ash in whole body were found among all groups ( P>0.05) . Final body weight, weight gain rate ( WGR) , specific growth rate ( SGR) of juveniles fed caridina were significantly higher than juveniles fed tubifex and brine shrimp ( P<0.05) , while condition factor ( CF) of juveniles fed Tenebrio molitor L. and tubifex was significantly higher than juveniles fed brine shrimp ( P<0.05) . For dry matter efficiency ratio, the raw fish block and tubifex groups was significantly higher than the other groups ( P<0.05) , the caridina group was significantly higher than the brine shrimp and Tenebrio molitor L. groups ( P<0.05) , and the brine shrimp group was significantly higher than the Tenebrio molitor L. group ( P<0.05) . Protein efficiency ratio had significant difference among different groups ( P<0.05) , and it presen?ted as tubifex group>caridina group>raw fish block group>brine shrimp group>Tenebrio molitor L. group. Lip?id efficiency ratio of juveniles in the raw fish block group was significantly higher than that in the other groups ( P<0.05) , that in the brine shrimp and caridina groups was significantly higher than that in the tubifex and Tenebrio molitor L. group (P<0.05), and that in the tubifex group was significantly higher than that in the Tenebrio molitor L. group ( P<0.05) . The content of crude protein in whole body of juveniles in the caridina group was the highest among all groups, and it was significantly higher than that in the Tenebrio molitor L. and brine shrimp groups ( P<0. 05 ); whereas, the content of ether extract in whole body of juveniles in the Tenebrio molitor L. group was the highest among all groups, and it was significantly higher than that in the oth?er groups ( P<0.05) . No significant differences in the contents of 17 kinds of amino acids, total amino acids, essential amino acids and delicious amino acids in whole body of juveniles were found among all groups ( P>0.05) , but the essential amino acids/non?essential amino acids in the tubifex, brine shrimp and caridina groups was significantly higher than that in the raw fish block and Tenebrio molitor L. groups ( P<0.05) . Proteases ac?tivity in gastrointestinal tract of juveniles fed raw fish and caridina was significantly higher than juveniles fed Tenebrio molitor L. and brine shrimp ( P<0.05) , while lipase activity in gastrointestinal tract of juveniles fed Tenebrio molitor L. was significantly higher than juveniles fed other diets ( P<0.05) . The lowest amylase ac?tivity in gastrointestinal tract of juveniles was observed in the brine shrimp group, and it was significantly lower than that in the other groups ( P<0.05) . The results suggest that caridina is optimal diet for juvenile Chinese gi?ant salamander, raw fish block comes second, and tubifex and Tenebrio molitor L. are final choices.