In vitro bull semen fertility after freezing-thawing with egg yold LDL: a comparison with Optidyl a commercial egg yold extend
Etude de la fertilité in vitro de la semence de taureau après congélation-décongélation avec du LDL du jaune d'oeuf de poule : Comparaison avec l'Optidyl, dilueur commercial à base de jaune d'oeuf
Résumé
Motility of bovine semen cryopreserved in Low-density lipoproteins (LDL) was analyzed and compared to semen cryopreserved with Optidyl(R), a commercial extender containing egg yolk. To evaluate the fertilizing ability of semen, we used in vitro fertilization test, whereas acrosome and plasma membrane integrity were also evaluated. The percentage of motile spermatozoa was near two fold higher after freezing in LDL than in Optidyl(R) 54.4% versus 30.2% (P<0.05). Integrity of the acrosome and the plasma membrane was maintained with both extenders. The cleavage rate was significantly higher after fertilization with semen frozen in LDL than with Optidyl(R) 63.0% versus 54.8% (P<0.05). No significant difference of blastocyst's number was observed after in vitro culture. However, the higher percentage of motile spermatozoa obtained with LDL extender suggests that a lower number of spermatozoa could be used in the straws for artificial insemination.