[Sperm production of "curimbatá" Prochí­­lodus scrofa Steindachner, 1881]

Abstract

Aiming to maximize the utilization of males during the hormonal induction, a spermatic evaluation of 3 years old males of "curimbatá" Prochilodus scrofa reared in confined conditions was accomplished in the Pindamonhangaba Fish Culture Experimental Station. Between October and December 1995, milt of 36 males was collected successively every 14 days after they had been individually marked and anesthetized. In the first three collections, it was observed that all the fishes produced sperm, however in the fourth collection only 34 males produced it and in the fifth only 16 fishes did. Mean values of semen volume collected increased in the second collection following a gradual decrease. The average of spermatic concentration in the first collection was 29.85 x 10⁶/mm³. There was a linear and cubic effect to all the studied characteristics. As the results obtained through thee spermatic evaluation in the fourth and fifth collection were inferior to those of the first three, we could conclude that 3 years old males of "curimbatá" may be utilized up to 3 times during their reproductive period without a significative loss of the quality of the semen.