Gonadal development of cultured Pampus argenteusin their first year of life

Gonadal development of the first year of life in cultured Pampus argenteus was studied histologically.At the age of first two months,testes were at stage Ⅰ,and then developed into stage Ⅱ in the following two months.At the age of 5,6 and 7 months,testes developed into stage Ⅲ,Ⅳ and Ⅴ,respectively.During winter(age of 8 to 10 months),testes degenerated into stage Ⅲ,and then developed again and matured at the age of 11 to 12 months.Ovaries developed more slowly than testes.It developed into stageⅠ at the age of 3 to 4 months,and at the age of 5 and 6 months,ovaries were found at the stage of Ⅱ and Ⅲ,respectively.During winter time,ovaries in fish at the age of 7 to 8 months degenerated into stage Ⅱ.After winter,ovaries developed again and matured at the 11th-12th month.The development of ovaries and testes was asynchronous.The results provided basic information for the gonadal development study and artificial breeding in Pampus argenteus.