Maedi-Visna virus was detected in association with virally exposed IVF-produced early ewes embryos

This study clearly demonstrates that (i) in vitro, ZP-free, early ovine embryos, which had been exposed to 103 TCID50/m MVV in vitro, are capable of transmitting the virus to susceptible GSM target cells, and that (ii) the IETS recommendations for handling in vivo produced bovine embryos (use of ZP-intact embryos without adherent material and performing ten washes) are effective for the elimination of in vitro MVV infection from in vitro produced ovine embryos. The absence of interaction between ZP-intact embryos and MVV suggests that the in vitro produced embryo zona pellucida provides an effective protective barrier.