绰斯甲河大渡裸裂尻鱼的年龄与生长特性研究

以绰斯甲河流域大渡裸裂尻鱼(Schizopygopsis malacanthus chengi)的微耳石和脊椎骨为年龄鉴定材料,对其进行了年龄鉴定,并比较了两种年龄鉴定材料的准确性,结果表明微耳石更适合于年龄鉴定。同时,以微耳石磨片为年龄鉴定和生长推算材料,对大渡裸裂尻鱼种群的生长特性进行了研究。结果显示:在相同年龄组内雌鱼个体显著大于雄鱼。雌、雄鱼体重与体长表现为异速生长:W♂=0.024 5×L2.793 4,W♀=0.021 3×L2.859 3。Von Bertalanffy生长方程为雌鱼Lt=32.319×1-e-0.087×(t+4.024)],Wt=439.165×1-e-0.087(t+4.024)]2.859 3;雄鱼Lt=23.195×1-e-0.213×(t-1.008)],Wt=169.307 2×1-e-0.213×(t-1.008)]2.793 4。雌、雄鱼的生长拐点年龄分别为8.1龄和6.0龄,对应的雌鱼体长和体重为L=21.06 cm,W=129.12 g;对应的雄鱼的体长和体重为L=15.18 cm,W=51.85 g。

Age and growth characteristics of Schizopygopsis malacanthus chengi in the Chuosijia River

This paper dealed with the lapilli and vertebra of Schizopygopsis malacanthus chengi,and compared to the agreement of age readings.The results showed that the lapillus was more suitable for the age determination.Meanwhile,the lapilli were used to determine the ages and back-calculate the growth of S.malacanthus chengi.The results show that the female grew faster than the male for the same age.The body weight grew with the body length and there were significant differences in growth patterns between males and females.The body length-weight relationship can be described by the following equations:W♂=0.024 5× L2.793 4,W♀=0.021 3× L2.859 3.Growth could be described by Von Bertalanffy equation:Lt=32.319×1-e-0.087×(t+4.024)],Wt=439.165× 1-e-0.087(t+4.024)]2.859 3;Lt=23.195×1-e-0.213×(t-1.008)],Wt=169.307 2× 1-e-0.213×(t-1.008)]2.7934 for females and males,respectively.The inflexion point of age for body weight and the corresponding body length and body weight were at 8.1 years,21.06 cm and 129.12 g for female,and 6.0 years,15.18 cm and 51.85 g for male.