Effect of different extenders on sperm viability of buck semen stored at room temperature

The use of egg yolk containing extenders in buck semen requires the washing of the semen due to the presence of egg yolk coagulating enzyme (EYCE) in the seminal plasma of the goat. Egg yolk prevents the effects of cold shock when semen is cooled. Alternatively, storage of buck semen at temperatures above 15 ◦C allows use of extenders without egg yolk. The aim of the study was to evaluate the effect of different extenders without egg yolk on the viability of buck semen stored at room temperature. Ejaculates were collected once from four adult bucks and split into five aliquots each and diluted with one of five extenders: Skim milk (Mi), Laiciphos® (Lai), Beltsville Thawing Solution (BTS), and Biociphos Plus® (Bio-5 and Bio-20). The diluted semen was stored at room temperature, except for Bio-5, which was cooled and stored at 5 ◦C. Sperm motility and acrosomal status were evaluated following 3, 8, 12, 24 and 28 h. Motility and acrosomal status were significantly influenced by the extenders and storage time (P < 0.001), while only sperm motility was influenced by the interaction between extender and storage time (P < 0.001). Progressive motility and acrosome integrity were maintained longer in milk-based extenders, e.g. Laiciphos®, compared to Biociphos Plus®. Storage at 5 ◦C in Biociphos Plus® was better for sperm viability than storage at 20 ◦C. No motile spermatozoa were recorded after 3 h of storage in BTS. In conclusion, the results of the trial indicate that milk-based extenders, especially Laiciphos®, preserved sperm motility and acrosome integrity better than Biociphos Plus®, when buck semen was stored at 20 ◦C for up to 28 h. © 2004 Elsevier B.V. All rights reserved.