日本七鳃鳗冬季两性形态及个体生殖力研究

采用SPSS13.0软件的t检验、回归检验和因子分析等方法,对2006年12月于黑龙江中下游萝北江段捕到的日本七鳃鳗(Lampetra japonica)的两性形态及个体生殖力进行了研究。结果表明:日本七鳃鳗雌雄个体的体长、体重、净体重和肥满度等指标在繁殖前没有显著差异,而性腺重和成熟系数两性差异显著。日本七鳃鳗的个体绝对生殖力平均为(101959.47±23259.82)粒,体长的相对生殖力(FL)平均为(2219.36±496.84)粒/cm,净体重的相对生殖力(FW)平均为(964.1±260.9)粒/g。体长绝对生殖力、体长相对生殖力(FL)和净体重相对生殖力(FW)均与卵巢重和成熟系数显著正相关。卵巢重、成熟系数、绝对生殖力、体长相对生殖力(FL)和净体重相对生殖力(FW)是与个体生殖力密切相关的主要因子,而体长、体重、净体重和肥满度可以间接地反映个体生殖力的大小。

Sexual Differences in Morphology and Individual Fecundity of Lampetra japonica in Winter

Individual fecundity and morphology of Lampetra japonica captured in Luobei section of the Heilongjiang River in December 2006,were studied by t-test,correlate and regression test,and factor analysis of SPSS13.0.The results showed that there was no significant difference in body length,body weight,net body weight and relative fatness between female and male L.japonica before breeding,while gonad weight and maturity coefficient had remarkable difference between female and male.Mean of absolute fecundity(F)of L.japonica was(101959.47±23259.82)eggs,mean of relative fecundity to length(FL) was(2219.36±496.84)eggs/cm and mean of relative fecundity to net weight(FW)was 964.1±260.9 eggs/g.F,FL and FW were significant positive with weight of ovary and maturity coefficient.Weight of ovary,maturity coefficient,F,FL and FW were main factors that were close related to dividual fecundity,while length of body,while body length,body weight,net body weight and relative fatness were indirectly related to individual fecundity.