昆明裂腹鱼繁殖生物学研究

Study on Reproductive Biology of Schizothorax graham

研究昆明裂腹鱼繁殖生物学周年变化,为开展昆明裂腹鱼人工繁殖、养殖以及对自然水域鱼类资源的增殖和保护提供理论基础。2014年7月-2015年5月,每月定期采集雌、雄昆明裂腹鱼各10尾。样品鱼为2008年子一代,均为6龄。雌鱼体长26~48 cm,体重380~1 600 g;雄鱼体长29~46 cm,体重425~1 250 g。结果显示:昆明裂腹鱼成熟系数雌鱼为(7.07±0.04)%,雄鱼为(3.72±0.01)%;属一次性产卵类型,繁殖期为2-4月,盛期为3-4月;Ⅳ期卵巢卵径1.6~1.8 mm占35%。绝对繁殖力为(9263±5241)粒,与体长呈曲线相关(F=2E-11L7.427,R2=0.912),与体重呈线性相关(F=0.017W-10.19,R2=0.958);相对繁殖力为(9.5±3.9)粒/g,与体长、体重均呈曲线正相关(Fw=0.05e0.156L、R2=0.846,Fw=14.37ln W-90.57、R2=0.871)。

Schizothorax grahami is primarily distributed in the upper Wujiang River and the stem and tributaries of lower Jinsha River,and is a key protected fish species in Guizhou Province. Recently,artificial breeding and culturing of Schizothorax grahami has developed rapidly because it tastes good and is highly nutritious. In this study,the annual variation in reproductive characteristics of Schizothorax grahami was investigated,based on data collected from July 2014 to May 2015. The objective was to provide a theoretical basis for artificial breeding and culturing of Schizothorax grahami and to conserve and enhance wild populations. From July 2014 to May 2015,ten female and male Schizothorax grahami specimens were collected each month at a fixed time and a total of 220 specimens were collected for study. All specimens were first filial generation,bred in 2008,with female body length of 26-48 cm and body weight of 380-1 600 g and male body length of 29-46 cm and body weight of 425-1 250 g. The gonad weight of each specimen and diameter of eggs from mature females were determined. Results indicate that male Schizothorax graham reach maturity at age three,with a gonadosomatic index of（ 3. 72 ± 0. 01） %,and females reach maturity at age four,with a gonadosomatic index of（ 7. 07 ± 0. 04） %. The spawning season of Schizothorax graham is from February to April,peaking in March and April. Eggs are demersal and adhesive,spherical in shape and golden yellow and gray white in color. The egg diameter of Schizothorax graham with ovaries at stage IV ranged from 1. 6mm to 1. 8mm. The absolute fecundity of female Schizothorax graham（ F） was（ 9 263 ±5 241） granules and exhibited a curvilinear correlation with body length（ F = 2E-11L7. 427,R^2= 0. 912） and a linear correlation with body weight（ F = 0. 017W-10. 19,R^2= 0. 958）. The relative fecundity of female Schizothorax graham（ Fw） was（ 9. 5 ± 3. 9） eggs/g,presenting curvilinear correlation with body length and weight,expressed as Fw= 0. 05e0. 156L（ R2= 0. 846） and Fw= 14. 37 ln W-90. 57（ R^2= 0. 871）.