Qualitative and quantitative evaluation of silver catfish sperm, Rhamdia quelen

Abstract

Qualitative and quantitative semen evaluation of silver catfish, Rhamdia quelen, the pH influence on spermatic motility, and the need of reproductive hormonal induction in males were the aims of the present study. Semen samples were collected in two phases: the first used 15 males for qualitative and quantitative semen evaluation and the second used 9 males to assess the influence of pH 4, 5, 6, 7, 8 and 9 on semen motility time of males submitted and not submitted to hormonal induction. In the first phase, mean semen volume collected was 0.41 ± 0.37 mL. Spermatic motility was between 60 and 70% whereas spermatic concentration was between 24,650,000-138,950,000 cells/mm³. In the second phase, three males were induced and a mean motility of 88.30% was found, whereas a mean motility of 72.5% was found in six males not submitted to hormonal induction. No significant difference was found in semen motility time between hypophysed and non-hypophysed males in the different pH levels. Males do not need to be induced to spawn.