Study of Sperm Evaluation Parameters to Estimate Cryopreserved Bovine Semen Fertility

In cattle production, reproductive biotechnologies such as artificial insemination with Cryopreserved semen samples show the same performance as insemination with fresh semen. The most representative method to evaluate semen fertilizing capability is through the results obtained by in vivo fertility. However, as it is difficult to apply this method in practice, routine laboratory tests can be used to evaluate semen quality. The aim of this work was to evaluate functional spermatic parameters in cryopreserved bovine semen samples from males presenting high and low field fertility rates. Semen samples were obtained from bulls presenting low or high fertility in a program of artificial insemination. Routine and functional parameters were determined in both groups. As regards routine tests, no significant differences were observed in progressive motility and vigor between samples of animals with high and low fertility in vivo, but differences were detected in vitality and acrosome integrity (p<0.05). Within functional tests, no differences were detected in thermo resistance and capacitation induction, but HOS test, acrosomal reaction induction and IVF showed significant differences (p<0.05). These results assert that routine parameters (progressive motility and vigor) have a limited value to predict field fertility. Therefore, the incorporation of some functional tests may offer a better estimation of fertilizing capability.