THE EPIDIDYMAL SPERM SURVIVAL INTERVAL FOLLOWING ORCHIDECTOMY IN DOGS

The aim of the study was to investigate the motility and viability of canine epididymal spermatozoa, collected from the epididymides following orchidectomy (castration), over a period of time. Sperm samples were collected at 25-28oC from the caudal epididymis, 0, 1, 3, 6, and 12 hours, after the castration of 75 fertile dogs (1-10 years old). Progressive motility and viability of the epididymal sperm decreased over a period of time, after the collection. The epididymal sperm motility was 82.3±6, 76.3±8, 72.0±7, 60.3±9, and 22.7±20% while the percentage of viable spermatozoa was 85.5±5, 78.8±7, 77.5±7, 64.4±7, and 27.1±21 at 0, 1, 3, 6 and 12 h, respectively. At 12 h, some samples showed neither motility nor viability, after flushing from the epididymides, while some samples still demonstrated high motility and viability (60-70%). An additional study showed that the motility of epididymal sperm, stored and collected at temperatures higher than 37oC, dramatically decreased within 3 hours. It can be suggested that any delay in epididymal sperm collection results in a deterioration in sperm quality. However, when the epididymis is processed at 25-28oC, within 3 hours, the sperm characteristics remain little affected and the spermatozoa can be used as gamete resources.