The present study was undertaken to induce gonadal maturation of Mrigal, Cirrhinus mrigala using Human Chorionic Gonadotropin (HCG) implants in captive conditions. The male and female fishes of C. mrigala were implanted intramuscularly with hCG implants at the dosage of 1000 IU/kg body weight, to study the effect of hCG hormone. Hormone implants were given once in two months during the experimental period of February to June. Histological observation in the ovary of C. mrigala revealed the presence of four types of growing oocytes namely perinucleolar, previtellogenic, vitellogenic and hydrated oocytes. Histological observation of the testis of C. mrigala showed the presence of five types of spermatogenic cell types namely spermatogonia, primary spermatocytes, secondary spermatocytes, spermatids and spermatozoa. Hence, the present study recommends that hCG implants can successfully be used to induce sustained maturation of C. mrigala in captivity even during off season. 

The present study was undertaken to induce gonadal maturation of Mrigal, Cirrhinus mrigala using Human Chorionic Gonadotropin (HCG) implants in captive conditions. The male and female fishes of C. mrigala were implanted intramuscularly with hCG implants at the dosage of 1000 IU/kg body weight, to study the effect of hCG hormone. Hormone implants were given once in two months during the experimental period of February to June. Histological observation in the ovary of C. mrigala revealed the presence of four types of growing oocytes namely perinucleolar, previtellogenic, vitellogenic and hydrated oocytes. Histological observation of the testis of C. mrigala showed the presence of five types of spermatogenic cell types namely spermatogonia, primary spermatocytes, secondary spermatocytes, spermatids and spermatozoa. Hence, the present study recommends that hCG implants can successfully be used to induce sustained maturation of C. mrigala in captivity even during off season. 

Body and testis weights, serum luteinizing hormone, follicle-stimulating hormone, and prolactin values and volume fractions of Sertoli cells, spermatogonia, early and late primary spermatocytes, and round and long spermatids were evaluated in 70-day-old male rats treated orally with 20 mg of zearalenone/kg of body weight daily for 5 weeks. A significant (P < 0.05) increase in serum prolactin concentration was consistently observed during the 5 weeks of treatment with zearalenone. Significant changes were not observed in any of the other variables evaluated.