白鲟年龄鉴定及其生长的初步研究

以齿骨和胸鳍条为年龄鉴定材料，通过其骨磨片比较研究，结果显示用胸鳍条鉴定白鲟的年龄较为可靠。所收集的６６尾白鲟样品中，根据胸鳍条鉴定年龄，幼鲟８尾，１－３龄。成鱼５８尾中，雄鱼３３尾，最低６龄，最高１１龄，多数个体为８－９龄。雌鱼２５尾，最低７龄，最高１７龄，多数为１０－１２。白鲟生长速度快，特别在第一年其长度生长最为突出。当年１０月份的幼鱼全长达５３－６１ｃｍ，１龄鱼平均全长７５ｃｍ。推算结果表明雌雄鱼在性成熟前生长无明显差异，性成熟后，雌鱼的长度及重量均大于相同年龄雄鱼。采用ＶＢＧＦ描述白鲟全长及体重的增长。

AGE DETERMINATION AND GROWTH OF CHINESE PADDLEFISH PSEPHURUS GLADIUS

Oberservation of compare with the sections of two calcified structrues, iepectoral fin ray and dentary bone from Chinese paddlefish Psephurus gladius were conducted. It reveals that the 3rd to 5th pectoral fin rays are optimal aging structrues for the fish. The age determination of the Chinese paddlefish indicated that 8 immature individuals were 1-3 years of age,58 mature individuals were 6-17 years old. Of these, the majority of 33 males, with the youngest age of 6 years old and the oldest 11, fell between 7-9 age groups; the most of 25 females, with the youngest 7 and the oldest 17, fell between 8-12 age groups. The rate of growth of the Chinese paddlefish appears to be rapid, especially in the first year of life. The Von Bertalanfy Growth Function (VBGF) for growth in length could be written as:for males Lt= 368.5 for females Lt=436.3 where Lt= total length in cm, t=age in years. The VBGF for growth in weight could be written as:for males Wt = 148.6 for females Wt= 264.0where Wt= weight in kg, t = age in year.