中华花鳅的生长和繁殖生物学的研究

Growth and Reproductive Biology of Chinese Spined Loach Cobitis sinensis

对采自四川省广元市旺苍县东河的113尾中华花鳅的生长和繁殖生物学进行研究。结果显示,旺苍县东河的中华花鳅体长34.92~102.85 mm,体质量0.34~9.84 g,净体质量0.31~8.09 g。分为5个年龄组,以2~4龄个体为主。生长以3龄为分界,3龄前生长速度快,3龄后生长速度减慢。体长(m1)与体质量(L)呈幂函数关系:m1=0.00001215L2.896,r2=0.939,接近等速生长。肥满度<1,雌性和雄性的Fulton肥满度差异不显著,雄性略小于雌性;而除1龄的个体外,其他年龄的雄性Clark肥满度均略大于雌性。雌、雄性比为1∶1.69。雌、雄鱼最小性成熟年龄均为2龄。精子在蒸馏水中的平均寿命为14 s;随NaCl溶液质量分数的增大,中华花鳅精子平均寿命先增后减,在NaCl溶液质量分数为0.25%时寿命最长,达184 s。绝对繁殖力为427~4047粒/尾,平均1949.82粒/尾;相对繁殖力为107.56~566.09粒/g,平均356.07粒/g。6月中旬至8月中旬为产卵盛期。分批产卵,且各批次生殖力大致相同。受精卵为微黏性的沉性卵。

In July 2012 and May 2013, 70 Chinese spined loach Cobitis sinensis were caught in traps and electrical fishing in Donghe River of Wangcang County, Guangyuan City, Sichuan Province and fixed in 10% formalin solution and then stored in 5% formalin solution, and another 43 samples were transported to the laboratory with plastic bag oxygenation. After routine biological measurements, the viscera of the tested fish were taken out, and the intestinal length, eviscerated weight and gonad weight were measured to investigate the growth and reproductive biology of the fish including food item analysis, male and female identification and sperm longevity. The Chinese spined loach had body length(L) of 34.92-102.85 mm, body weight(m) of 0.34-9.84 g, and eviscerated weight of 0.31-8.09 g, and was divide into 5 age classes, determined by vertebra, with dominant 2-4 age classes. The Chinese spined loach had good growth before 3 year old, low growth afterwards, with function between body length and body weight of m1=0.00001215L2.896, r2=0.939, nearly isometric growth. The relative condition factor was generally found to be less than 1, without significant difference in Fulton condition factor between female and male(P>0.05), even though smaller in males than in females. For the over 1 year old loach, however, there was slightly larger Clark condition factor in males than that in females. The Chinese spined loach had sexual ratio(♀∶♂) of 1∶1.69, and maturity at two years old age. The sperm survived for 14 seconds in distilled water, and longevity of the sperm was shown to be increased first and then decreases with the increase in NaCl concentration, with the maximal longevity(184 s) at NaCl concentration of 0.25%. The Chinese spined loach had absolute fecundity of 427-4047 eggs per female, with mean value of 1949.82 eggs, and relative fecundity of 107.56-566.09 eggs/g, with mean value of 356.07 eggs/g. The peak period of spawning was observed from mid-June to mid-August, spawning in batches, and roughly the same fecundity each batch, and the zygote is demersal and slightly viscous.