Penetration assay of frozen jaguar (Panthera onca) sperm in heterologous oocytes

Abstract

Assisted reproductive technologies can be viewed as one potential approach for safeguarding wild species. In this study were evaluated the fertility of captivity male jaguar (Panthera onca) and different capacitation media using the golden hamster zona free oocyte penetration assay. We used frozen/thawed semen from 3 animals housed at Bosque dos Jequitibás, Campinas/SP, to test the Percoll gradient, Swim-up and Swim-up + 1 h incubation (5% CO2 / 38°C), considering as penetration the spermatozoa head descondensation visualized within the oocyte. The results rate was greater for Percoll (26.5%) as compared to Swim-up (8.1%) (X2 = 19.93; p < 0.05). It was not observed penetration with Swim-up + 1 h incubation (5% CO2 / 38°C). It is concluded that Percoll and Swim-up are efficient methods to perform the golden hamster zona free oocyte penetration assay using frozen/thawed jaguar (Panthera onca) spermatozoa. The low rate of penetration could be related to the high rate of morphological abnormal spermatozoa observed in the samples examined.