YY super males have better spermatic quality than XY males in red tilapia Oreochromis niloticus

Abstract

The influence of sex - related chromosomal arrangement in an YY and XY population of Oreochromis niloticus males was investigated in this study. A better spermatic mobility, motility, viability, confluence and less abnormality were found in double Y - chromosome males (YY - males), compared to XY - males; however, this better spermatic quality did not correlate with the body weight of individuals which was significantly better in XY - males. This study establishes the influence of YY - re lated sequences over spermatic quality and indicates the usefulness of the YY technology as a strategy to obtain better fish breeders and genetically male individuals for a tilapia farming program.