DETERMINATION OF SEX AND SEXUAL MATURATION STAGES IN CULTURED ACIPENSER NUDIVENTRIS USING BIOPSY METHOD

Sturgeon fish take long time to mature sexually and determination of sex and sexual maturity stages is important in artificial rearing of the fish. Sex determination by macroscopic method has thus far been impossible for the fish at juvenile stages. Gonad biopsy and its histological examination is one way for detecting male and female sturgeon fishes. To do so, we collected gonad samples from 13 five year old and 17 six year old specimens of the cultured Acipenser nudiventris. Samples were studied by light microscope after fixing and histological practices.
Of the 13 five years old specimens, only 3 (23.1%) were male and 10 (76.9 %) were females. From 17 six years old fish, 10 (58.8%) were males and 7 (41.2%) were females. Histological studies showed that all male fish were at stage IV, but 5.8 % of all females were at stage I, 41.2 % were at stage II and 53 % were at stage II-III of sexual maturation. We also showed that in the studies sample, males reached maturity sooner than females.