Soybean lecithin is suitable cryoprotectant for cryopreservation of ram semen

Abstract

The purpose of the present study was to evaluate ram semen in vitro fertility after the freezing–<br><br>thawing process with extenders containing soybean lecithin. Soybean lecithin levels of 0.5, 1 and<br><br>2% (w/v) were assessed in combination with 7% glycerol in a basic Tris medium. Bioexcell was<br><br>used as control treatment. Semen samples were diluted with extenders and then frozen. The<br><br>sperm parameters were assessed after thawing for motility, viability and capacitation status.<br><br>Fertility was recorded as cleavage rate at 3day and blastocyst rate at 8day after in vitro<br><br>fertilization (IVF). Significant effects of various concentration of soybean lecithin were noted for<br><br>the parameters investigated (P≤0.05). The percentage of motility was recorded to be 41.8%,<br><br>51.9% and 39.7% for 0.5, 1 and 2% lecithin respectively. Also the percentage of viable<br><br>spermatozoa was estimated to be 36.08, 48.06 and 35.7 for 0.5, 1 and 2% lecithin respectively.<br><br>Lecithin at 1% had more positive effect than other concentrations. Bioexcell produced 49.18%<br><br>percentage of motile spermatozoa and 46.8% viable spermatozoa. No significant differences in<br><br>the staining patterns of capacitation status were observed. In IVF experiment, the cleavage rate<br><br>being significantly higher in oocytes fertilized with semen cryopreserved in 1% Lecithin.<br><br>Different concentration of lecithin had no effect on embryo development. Results indicated that<br><br>soybean lecithin is suitable cryoprotectant for cryopreservation of ram semen. Animal origin free<br><br>extender based on soybean lecithin we have investigated here is a viable alternative to traditional<br><br>egg yolk-based extenders.