Effect of chilled storage on sperm quality of basa catfish (Pangasius bocourti)

Basa catfish (Pangasius bocourti) is an indigenous species of the Lower Mekong River with increasing aquaculture value in Southeast Asia. Short-term semen storage has proven to be a valuable tool for assisted reproduction in fish, but little information is available on basa catfish. The present study was aimed at evaluating the effect of short-term semen storage on the sperm quality of basa catfish. Semen samples were kept at 4 degrees C for 7 days, either undiluted or diluted with Ca-F HBSS at different ratios (1:1, 1:3, and 1:6; semen:medium). Results showed that sperm quality was significantly affected by the time of chilled storage, characterized by a decline in sperm motility, viability, mitochondrial membrane potential (MMP), ATP content, and increased level of lipid peroxidation throughout the storage period. Compared with undiluted semen, diluted in Ca-F HBSS allowed better preservation of sperm quality during 7 days of chilled storage; dilution ratio at 1:1 was more effective than higher ratios (1:3 and 1:6) for prolonging sperm storability. In addition, sperm motility, viability, and ATP content decreased more rapidly than MMP, suggesting these indicators are more sensitive in detecting sperm damage of basa catfish during short-term chilled storage. These results obtained here will contribute to a better understanding of reproductive management in this species.