Histological Observations on the Gonadal Development of Nibea albiflora

Gonadal development of the cultured Nibea alibiflora was studied using histological techniques. The results indicated that the gonadal development of N. alibiflora in their first sex mature stage was divided into five stages based on the cytogic and physiological characteristics. Before the age of 2 month,testes and ovaries of the fish were at stage Ⅰ. The ovaries were at stage Ⅱ in 5 month, at stage Ⅲ in 11 month, at stage Ⅳ in 23 month and matured(stageⅴ) in 24 month. The testes were at stage Ⅲ in 3 month,at stage Ⅳ in 6 months and matured in 11 months(stageⅴ). The development of testes was faster than that of ovaries. Testes developed significantly faster than ovaries. The GSI of N. alibiflora obviously increased in April and May of the second and third year after hatching. Especially at the age of 24 month,the GSI coefficient significantly increased, which is the indicative of reproductive activities.