Experimental collection and transfer of embryos from bovine immunodeficiency virus (BIV) infected cattle

Three experiments were conducted to determine whether the lentivirus, bovin e immunodeficiency virus (BIV) is likely to be transmitted via embryo trans fer. In the first experiment, embryos collected from BIV-negative heifers w ere exposed in vitro to BIV for 24 h, washed and then tested for the presen ce of the provirus. In the second experiment, embryos obtained from BTV-neg ative heifers were transferred to the uterine hems of BIV-infected heifers; 24 h later these embryos were recovered and tested for the presence of BIV . In the third experiment, embryos were collected from heifers experimental ly infected with BIV and then transferred to BIV-negative recipients. In al l three experiments, (BIV) proviral DNA was not detected by PCR in associat ion with any oocytes, embryos, follicular fluid, oviductal or uterine washe s. Twelve single embryos collected from BIV experimentally infected donors were transferred to BIV-negative recipients resulting in the birth of 7 cal ves all of which were also negative for BIV; the recipients remained BIV-ne gative throughout the experiment. In conclusion, this study demonstrates th at it is possible to produce transferrable stage embryos from donors infect ed with BIV and that such embryos are unlikely to transmit this agent eithe r to the recipients or the resulting offspring. (C) 2001 by Elsevier Scienc e Inc.