Evaluating the effect of semen storage and dilution rate on boar sperm quality

This study analyzed the effect of boar semen storage and dilution rate on sperm motility, swimming patterns and kinematics. It used 35 sexually mature, healthy boars, with an average age of 19.0 +/- 10.34 months and known fertility. Samples were separated into four treatments according to dilution ratio (1:1, 1:4, 1:8 and 1:16; v:v) with Androstar Plus (R) and refrigerated at 17 degrees C in the dark for 96 h. Subsamples were analyzed at 12, 24, 28, 72 and 96 h using the ISAS (R) v1 Computer-Assisted Semen Analysis System (CASA). Total and progressive motility decreased (P < 0.05) as semen storage time increased. The percentage of morphological abnormalities increased after 48 h of semen storage. Samples diluted 1:1 (v:v) had higher values of total motility and faster spermatozoa compared to other dilution rates. It was concluded that sperm motility, swimming patterns and plasma membrane integrity showed a significant downward pattern as semen storage time and dilution rate increased.