摘 要:為探讨养殖密度对瓦氏黄颡鱼幼鱼生长性能、肌肉成分、血液生理生化指标的影响,选用初始体重为(25.23±0.09)g的瓦氏黄颡鱼幼鱼,分别设置G1、G2、G3、G4试验组,养殖密度分别为0.50、1.01、1.51、2.02 kg·m-3 (即20、40、60、80尾·m-3),在循环水养殖系统中进行60 d的养殖试验。结果表明,幼鱼的终末体长、终末体重、特定生长率、肥满度随养殖密度增大而下降,饲料系数则呈上升趋势;G1组瓦氏黄颡鱼幼鱼终末体长、终末体重、特定生长率、肥满度、存活率显著高于G3组和G4组(P<0.05),但G1、G2组鱼体肥满度、饲料系数及存活率无显著差异(P>0.05)。肌肉中蛋白质含量随养殖密度增加而上升,脂肪含量则呈下降趋势,G1组瓦氏黄颡鱼肌肉蛋白质含量显著低于其他处理组(P<0.05),脂肪含量显著高于其他处理组(P<0.05)。血液白蛋白、溶菌酶水平随养殖密度增高呈下降趋势(P<0.05),G1组显著高于G3、G4组(P<0.05);谷丙转氨酶、谷草转氨酶水平随养殖密度增高呈升高趋势(P<0.05),G1、G2组显著低于G3、G4组(P<0.05);在试验条件下,养殖密度对鱼体抗氧化能力影响不显著(P>0.05)。综合分析,在本试验条件下,体质量为(25.23±0.09)g的瓦氏黄颡鱼适宜放养密度约为1.01 kg·m-3,该结果可为工厂化养殖提供参考依据。
关键词:瓦氏黄颡鱼;养殖密度;生长;肌肉组分;生理生化
中图分类号:S 965 文献标识码:A文章编号:1008-0384(2018)07-670-06
Abstract: The purpose of this study was to investigate the effects of stocking density on growth, muscle composition and blood parameters of Pelteobagrus vachelli juveniles. A 60 day feeding trial was conducted to evaluate the effects of stocking density on growth, muscle composition and blood parameters of juvenile yellow catfish (Pelteobagrus vachelli). A total of 600 juvenile yellow catfish with an initial body weight of (25.23±0.09) g were randomly distributed into four different stocking density groups with 3 replicates per group of G1 (0.50 kg·m-3, 20 fish·m-3), G2 (1.01 kg·m-3, 40 fish·m-3), G3 (1.51 kg·m-3, 60 fish·m-3), G4 (2.02 kg·m-3, 80 fish·m-3). The results showed that the growth and feed coefficient of juvenile yellow catfish were effected significantly by stocking density (P<0.05). Final body length, final body weight, specific growth rate and condition factor decreased with an increase in stocking density, whereas the feed coefficient showed the opposite tendency (P<0.05). Final body length, final body weight, specific growth rate, condition factor and survive rate of fish in G1 were higher than those in G3 and G4 (P<0.05),but the condition factor,feed coefficient and survive rate of G1 and G2 were with no significant difference(P>0.05).Muscle protein content increased significantly with the increase in stocking density, whereas muscle lipid content decreased significantly (P<0.05). Muscle protein content of fish in G1 was lower than others, whereas the lipid content showed the opposite tendency (P<0.05). Lower stocking density groups had higher albumin content and lysozyme activity in blood (P<0.05), whereas glutamicpyruvic transaminase and glutamicoxalacetic transaminase activities showed the opposite tendency(P<0.05). No significant difference was observed in blood total antioxidant capacity among all groups(P>0.05). In conclusion,1.01 kg·m-3 was considered to be a suitable stocking density for juvenile yellow catfish with an initial body weight of (25.23±0.09) g.