Effects of liquid storage on amidase activity, DNA fragmentation and motility of turkey spermatozoa

Short-term liquid storage of turkey semen is of great interest in the management of turkey reproduction due to the extensive use of artificial insemination. This study examined changes in DNA fragmentation (using a comet assay), sperm motility characteristics (using computer-aided sperm analysis), and amidase activity (using a colorimetric assay) of turkey sperm stored for 24 and 48 h. In addition we found that turkey spermatozoa contain besides acrosin, additional two serine proteinases of molecular weight of 34 and 42 kDa. We found that, after 48 h of liquid storage, decreases in sperm motility characteristics and increases in amidase activity and DNA fragmentation occurred. An increase of amidase activity was found after 24h. Decreases in sperm motility and increase in DNA fragmentation were found after 48 h of storage. These data suggest that a decrease in turkey sperm quality during short-term storage is related to disturbances to the acrosome, presumably related to premature activation of acrosomal serine proteinases, and to a lesser extent a decrease in sperm motility characteristics and damage of sperm DNA.