Cryopreservation of epididymal spermatozoa collected by needle biopsy fromcynomolgus monkeys (Macaca fascicularis)

We have examined the motility, morphology, and cryopreservation of epididym al spermatozoa collected by needle biopsy from cynomolgus monkeys (Macaca f uscicularis). At collection, epididymal sperm (23 x 10(6) +/- 4 x 10(6) spe rm/sample; 611 x 10(6) +/- 116 x 10(6) sperm/ml; n = 18) were alive (79 +/- 2%), motile (67 +/- 2%), and exhibited intact membranes (65 +/- 2%). Sperm maintained at room temperature in handling medium exhibited decreased moti lity over time, but head-to-head agglutination was limited. Tris egg-yolk e xtender containing 6% glycerol and dimethylsulfoxide (DMSO) did not signifi cantly affect functional morphology, whereas extender containing propanedio l significantly reduced motility, survival, and membrane integrity. Cryosto rage reduced all measures of functional morphology independent of cryoprote ctant. Post-thaw motility was superior for glycerol and DMSO compared to pr opanediol. Variation in glycerol concentration (4, 6, and 8%) produced equi vocal effects on sperm functional morphology post-thaw. Needle biopsy may b e a useful technique for laboratory and field-based collection of spermatoz oa from nonhuman primates.