In vitro fertilization of rabbit ova

A repeatable procedure for in vitro fertilization of rabbit ova in which the percentage of ova fertilized is consistently high has been developed. When ova were recovered and subsequently incubated in vitro with capacitated spermatozoa at 37° or 39°C levels of ova fertilized were 15, 24 and 28% when 73–78%, 83%, and 90% relative humidities, respectively, were maintained. Twenty‐one per cent of all ova in these experiments were fertilized. When the ova were recovered at 30–39°C and subsequently incubated at 37° or 39°C with capacitated spermatozoa under paraffin oil only 19% of the ova were fertilized. However, when ova were recovered and subsequently incubated with capacitated spermatozoa and fluids from the female tract all under paraffin oil at 39°C with 96–97% relative humidity levels of ova fertilized were 30, 32 and 73% when stored oviduct fluid, stored uterine fluid, and fresh uterine fluid, respectively, were included in the media. Thirty‐seven per cent of all ova incubated with capacitated spermatozoa under paraffin oil were fertilized. This system with the inclusion of fresh uterine fluid in the medium yields the highest percentage of fertilization with greater consistency than any other system for in vitro fertilization of rabbit ova ever reported.