LAUSR

Free amino acids are found in spermatozoa and seminal plasma. Their qualitative and quantitative presence have been affected by many factors. Under in vitro storage conditions, their effects on spermatozoa in animal species and also human have been concerned over the last decades. In this study, the effects of tryptophan, phenylalanine and cysteine on DNA integrity, lipid peroxidation, viability and motility parameters in spermatozoa of the common carp Cyprinuscarpio were assessed during short-term storage. Spermatozoa were incubated at 1, 5, 25, and 50 mM of these amino acids in vitro at 4 °C in a time?dependent manner 6, 24, and 48 h . The supplementation of cysteine, phenylalanine and >5 mM of tryptophan to the incubation medium attenuated the spermatozoa motility parameters and viability. Particularly, >1 mM of cysteine completely inhibited progressive motility and decreased viability to