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在28—32℃下,黄鳝受精卵经9—10天孵化即可出膜。至第2年9月可长至15.5—21.0cm。对190尾黄鳝实测及观察表明:黄鳝性变化最小体长为26cm。26cm以下全为雌体;28—34cm雌性、间性发育占较大比例;44cm以上雄性发育个体占68.8％。年龄鉴定:2龄前为雌性发育;间性多为3龄;雄性则出现在4龄以上。各年龄组平均退算体长:2龄23.28cm;3龄35.59cm;4龄49.98cm。根据生长指标可将黄鳝(1—4龄)划为三个阶段:1—2龄生长比速大(0.68),为第一生长阶段;2—3龄生长比速0.4,为第二生长阶段;3—4龄生长比速0.36,为第三生长阶段。
At 28-32 ℃, the eel fertilized eggs hatched after 9-10 days to the membrane. By the second year in September can grow to 15.5-21.0cm. The measurement and observation of 190 eel showed that the minimum body length of eel varied 26cm. 26cm below the female body; 28-34cm female, between the larger proportion of sexual development; 44cm or more male individuals accounted for 68.8%. Age identification: 2 years before the female development; mostly inter-3 age; males appear above the age of 4. The average body length of each age group: 2 years old 23.28cm; 3 age 35.59cm; 4 age 49.98cm. According to the growth index, the eel (1-4 years old) can be divided into three stages: the growth ratio of the first to the second instar (0.68) is the first growth stage; the growth rate of the second to third instar is 0.4 and the second growth stage ; 3-4-age growth rate of 0.36, for the third growth stage.