| Abstrakt: |
Studies were conducted in an effort to improve the convenience and objectivity by which the percentage of bovine spermatozoa with intact acrosomes (PIA) could be determined using differential-interference-contrast microscopy. The acrosomal integrity of spermatozoa from each of six bulls was evaluated in wet, seminal smears at 0, 2, 4 and 8 hr of post-thaw incubation at 37 C and compared to that of spermatozoa from the same samples fixed in buffered-glutaraldehyde solutions at each incubation interval, and evaluated after 0, 1, 8 or 29 days of room temperature storage. Spermatozoa were fixed in solutions of .2% glutaraldehyde in phosphate-buffered saline, with and without .15 M sodium cacodylate. When averaged over post-thaw incubation intervals and bulls, there was no difference (P>.25) in the PIA among unfixed samples and those preserved in either fixative solution and stored for up to 29 days. A higher percentage of fixed spermatozoa possessed intact acrosomes when the solution contained sodium cacodylate (P<.01).In another experiment, raw semen from each of six bulls was incubated at 37 C for 0, 1, 2, 4 and 6 hours. At each incubation interval, aliquots of semem were evaluated in 2.9% sodium citrate or fixed and evaluated on days 1, 8 and 29 of storage. The PIA for unfixed samples was lower (P<.01) than for fixed samples (74 vs89). Storage time had no effect (P>.10) on the PIA of fixed spermatozoa. |
