Does semen quality of Colossoma macropomum change the productivity of larvae during the reproductive period?

Abstract

This study aimed to analyze the sperm quality of Colossoma macropomum, during the reproductive period. A total of 23 males of C. macropomum in the breeding season were used. Male gametes were collected after the hormone induction protocol using volumetric syringes for quantitative and qualitative analyses throughout the reproductive season, the fish were captured every 15 days. The following parameters were evaluated: volume, motility rate, motility time, sperm concentration, sperm morphology, fertilization rate, and hatching rate. There was no effect of period within season for semen volume, motility time and sperm concentration. For motility rate a quadratic effect was observed between collection periods. As for sperm morphology, there were differences (p < 0.05) in the probability of occurrences of normal spermatozoa, primary and secondary abnormalities as a function of collection period. For the fertilization rate a quadratic effect was verified and the hatching rate declined linearly throughout the reproductive period. Changes in the qualitative parameters of C. macropomum semen during the reproductive period were observed. In terms of the sperm quality of C. macropomum, the aging process of the spermatozoa is evident and consequently interferes in the fertilization and hatching rates, being more accentuated in the last month of the reproductive season.