Effect of using preserved homologous prostatic fluid as flushing and thawing medium on canine epididymal sperm characteristics during freezing-thawing process

Abstract

This study had investigated the effects of preserved homologous prostatic fluid (PPF) to canine caudal epididymal sperm characteristics which exposed prior to cooling, after thawing or at both times of cryopreservation. This study also determined whether PPF had any influence on post-thawed canine caudal epididymal sperm after stored at room temperature (approximately 25˚C) or 4˚C. The caudal epididymal spermatozoa were collected from 20 dogs. After recovery and thawing, sperm progressive motility, sperm viability and sperm plasma membrane integrity were evaluated. Sperm progressive motility and sperm viability of post-thawed epididymal sperm were evaluated after 30, 60 and 120 minutes storage. After recovery, the sperm progressive motility (P = 0.001) and sperm plasma membrane integrity (P = 0.004) were significantly higher in the PPF group compared to egg yolk-tris extender (EE-I). While, they were not significantly different between groups after thawing. Sperm progressive motility and sperm viability of all groups significantly decreased after 30 minutes storage (P < 0.05). At 120 minutes after thawing, sperm viability was not significantly different among all groups, however, sperm progressive motility declined significantly (P < 0.05). This study showed that preserved homologous prostatic fluid was more suitable to be used as a flushing medium than the egg yolk-tris extender. Also, it can be used as a thawing medium instead of the tris buffer for canine caudal epididymal sperm cryopreservation.