Combined Single-Straw Packaging of Cryopreserved Stallion Epididymal Sperm and Separated Homologous Seminal Plasma

Retrograde flushing collection and freezing of dromedary camel epididymal spermatozoa with seminal plasma

The objectives of this study were to describe the parameters of dromedary camel epididymal spermatozoa collected by retrograde flushing (RF) technique and to evaluate the freezability of the collected sperm, diluted with and without the supplementation of seminal plasma (SP). Two experiments were conducted: in Experiment 1, ES were recovered within 6-8 h after castration; selected samples were diluted with a Tris-citrate egg-yolk glycerolated buffer and frozen. In Experiment 2, epididymides were stored for 24 h at 4 °C before RF and semen samples were frozen after dilution with a Tris-lactose egg-yolk glycerolated extender with and without 15% SP. In Experiment 1, eight semen samples were obtained from ten epididymides with a mean of 500 × 106 total spermatozoa recovered, per flushed epididymis. Mean post-thaw motility and progressive motility were 75 and 17%, respectively. In Experiment 2, 15 samples were collected, out of the 18 epididymides (mean number of collected spermatozoa: 700 × 106), and 13 of these samples were of excellent quality. Post-thaw parameters were not satisfactory but the supplementation of the freezing medium with 15% SP improved the progressive motility and kinematic parameters of the spermatozoa.