不同虹鳟品系异速生长的比较分析

研究测量了渤海虹鳟、丹麦虹鳟、美国道氏虹鳟、美国加州虹鳟和挪威虹鳟等5个虹鳟品系4年龄148个个体体重和20个形态学性状。应用静态联合异速生长模型同时估计多个体型性状对体重、纵向性状对体长、垂直性状对体高和横向性状对体宽的异速生长指数。首先建立每个虹鳟品系相对性状的最优联合静态异速生长指数方程,采用Newman-Keuls t检验法进行虹鳟品系间每个最优异速方程中异速生长指数的多重比较。结果表明,每个虹鳟品系存在显著不同的偏异速生长指数分布,其中全长与体重、体高与体重间存在较高的异速生长关系。在5个虹鳟品系中,头长、头宽、眼径、吻长、尾柄长、臀鳍高和臀鳍基长等7个形态性状相对体重的异速生长指数都不显著。背吻距与体长和尾柄高与体高在5个虹鳟品系中都存在显著的异速生长关系,但是品系间的多重比较却完全显著。本文通过对不同虹鳟品系异速生长指数的统计比较,分析它们之间的形态变异特点,为虹鳟及其他水产动物品系的形态学鉴别提供了一种有效的理论方法。

Statistical Comparison for Different Strains of Rainbow Trout (Oncorhynchus mykiss) in Growth Allometries

Body weight and 20 morphological characters were observed in 148 four-year old,5 rainbow trout strains including Bohai,Demark,America Oncorhynchus mykiss,California and Norway rainbow trout.A joint static allometry model was used to simultaneously estimate allometric scalings with multiple body shapes to body weight,longitudinal sizes to body length,vertical sizes to body height and transversal sizes to body width.Multiple comparisons of partial allometry scalings at the same trait between different rainbow trait strains were conducted with Newman-Keuls test after the best joint static allometry scaling model was established by stepwise regression analysis.The results showed that each strain of rainbow trout performed significantly different partial allometry scalings.Multiple morphological traits to body weight,total length or body height had the maximum value of allometry scaling.Non-significant allometric associations were found between head length and body weight,head width and body weight,eyes interal and body weight,mouth length and body weight,caudal peduncle length and body weight,anal fin depth and body weight as well as anal fin base length and body weight among five strains for rainbow trout.In addition,all strains showed significant allometry scalings for dorsal snout distance to body length and caudal peduncle depth to body depth.By comparing the allometry scalings among different strains for rainbow trout and analyzing their morphological variation characteristics,an effective theoretical method was proposed to identify morphological feature of strains for rainbow trout and other aquatic animal.