乌江泉水鱼个体生殖力的研究

2011年3-6月和9-12月,在乌江思林江段采集性腺达Ⅲ期的泉水鱼(Pseudogyrinocheilus prochilus)雌鱼个体,测量了卵径,并研究了其个体生殖力及其与多项生物学指标的关系,调查样本由1+～3+龄组成.结果表明,泉水鱼的绝对生殖力(F)平均值为3 606粒,体长相对生殖力(FL)平均值为19.4粒/mm,体重相对生殖力(FW)平均为27.0粒/g;个体绝对生殖力和体长相对生殖力与体重和净体重均呈二次函数相关,与性腺重呈幂函数相关,体重相对生殖力与性腺重和成熟系数分别呈幂函数和对数函数相关.依据卵径频数分布结果推测,泉水鱼属于分批产卵鱼类.

Individual Fecundity of Pseudogyrinocheilus prochilus in Wujiang River

From March to June and September to December 2011, the matured female Pseudogyrinocheilus prochilus were collected from Wujiang River. Their ages were identified by the scales, and their body length, body mass, gonad mass and other biological indices were measured. Egg diameters were measured with the aid of a microscope. Individual absolute fecundity were obtained through counting all eggs, and used for calculating the relative fecundity per millimeter, relative fecundity per gram. Based on these measurements and calculations, the relationships between the individual fecundity and the biological indices of P. prochilus in Wujiang River were studied. The ages of the specimens ranged from 1+ to 3+ years old, and the individual absolute fecundity and relative fecundity per millimeter were quadratically correlated with body mass and net body mass, and power correlated with gonad mass. The relative fecundity per gram was power correlated with gonad mass, and logarithmically correlated with mature coefficient. Multiple regressive analysis showed that the individual absolute fecundity was significantly correlated with gonad mass and net body mass. The relative fecundity per millimeter was significantly correlated with gonad mass and condition factor. The relative fecundity per gram was only correlated with mature coefficient. The distribution of egg diameter showed that P. prochilus was batch spawner.