In Vitro Comparison of Soybean Lecithin Based-Extender with Commercially Available Extender for Ram Semen Cryopreservation

Egg yolk is the main cryoprotectant agent in semen freezing extenders which is used in order to protect spermatozoa against cold shock. However, elimination of animal bioproducts from the cryopreservation protocol is becoming mandatory. Therefore, the aim of this study is to compare a previously studied, homemade soya bean lecithin based extender with a commercially available extender for ram sperm cryopreservation. Samples from three rams were pooled and split into two equal aliquots and diluted (1:20) with i%lecithin - 7%glycerol (L1G7) and Bioxcell®. The effects of L1G7 and Bioxcell® on sperm parameters and the in vitro fertilization ability of frozen-thawed ram spermatozoa were assessed. The results of this study revealed no difference between the two extenders in terms of motility, viability, and capacitation status. The results of in vitro fertilization in terms of rate of blastocyst formation were similar for both extenders, but significantly lower than that of freshly processed ram sperm. We conclude that both extenders are suitable for ram sperm cryopreservation