Comparison of a fluoresceinated lectin stain with triple staining for evaluating acrosome reactions of dog sperm.

In this study a technique which utilized a fluoresceinated lectin and a fluorescent supravital stain was compared with the conventional triple stain technique for evaluating the viability and acrosomal status of dog sperm. Ten semen samples obtained from 6 normal beagle dogs were evaluated after incubation in vitro with canine capacitation medium. Sperm viability and acrosomal status were assessed at 0, 4, and 7 hours of incubation. Both staining techniques were capable of detecting the increase in spontaneous acrosome reactions which occurs during in vitro capacitation of dog sperm. High positive correlations were observed between the fluorescent stain and the triple stain in the mean values for the percentage of viable sperm and for the percentage of acrosome-reacted sperm among the viable sperm (r = 0.91, r = 0.97, respectively). However, the fluorescent staining techniques could be carried out much more rapidly than the triple stain technique, and the slides prepared with fluorescent stain were more easily scored because of the higher intensity and greater consistency of staining. These characteristics make the fluoresceinated lectin and the fluorescent supravital stain superior for evaluating acrosome reactions and viability of dog sperm.