(Seminal characteristics of curimbatá, Prochilodus scrofa, Steindachner, 1881)

Abstract

The purpose of this paper was to study the seminal characteristics and indirect methods of evaluation of the sperm of "curimbatá", Prochilodus scrofa, caught at Mogi-Guaçu River, Pirassununga (São Paulo), during the reproductive season of 1984 and 1985. The seminal evaluation and the values obtained when estimated by confidence interval (95%) were: percentage of sperm motility 82.01 to 86.79%; percentage of live sperm by differential staining method 87.54 to 90.72%; sperm concentration 32.50 to 35.38 x 10⁶/mm³ The correlation coefficient between spermatozoa concentration and the spermatocrit was found to be r = 0.95* and the regression equation was: Y = -4347961 + 1157296.X, where Y represents the spermatozoa concentration per mm³ and X, the spermatocrit per milimeter. The methylene-blue reduction test was related with total spermatozoa concentration and with the number·of live spermatozoa for 42 fishes. The correlation coefficients (r) obtained were -0.43* and -0.65* respectively and were statistically significant (P < 0.05).