Abstract
The effect of concentration was examined of sodium laurylsulfate (SLS) in the initial and/or final diluents on the motility and acrosome morphology of frozen boar spermatozoa. The sperm-rich fraction collected from Landrace boars was centrifuged at room temperature and resulting sperm pellet was resuspended in a Tris-citric acid-glucose (TCG) solution (10×108 cells/ml). The sperm suspension was diluted 1:4 with the intitial diluent, TCG solution supplemented with egg yolk (10-30% v/v) and SLS (0-4 mg/ml), and further diluted 1: 1 with the final diluent containing 2% (v/v) glycerol after cooling to 4°C. Sperm samples were frozen on dry ice by the pellet method. The pellets were thawed at 40°C in dry test tubes. The post-thaw percentages of normal acrosomes and progressively motile spermatozoa, and the percentage of the latter after 3-hr post-thaw incubation at 37°C were improved by the addition of SLS. It was suggested that addition of SLS might be made at the initial and final dilutions, or at the final rather than the initial. The optimum concentration of SLS in the diluent containing 20% (v/v) egg yolk was considered to be 1.2 mg/ml when added at the both dilutions, and 2.0-2.8 mg/ml when added only at the final.
