The first part of the study resulted in seroconversion of all animals after insemination and this was in agreement with reports of other authors [24,25]. Although in the present study donors were not tested for viremia, postmortem findings indicate that the virus was in the blood and reached the reproductive tract by the day of embryo collection (7 days after insemination). This observation points out the presence of an infectious intrauterine environment as a possible source of contamination of recovered
embryos. In another study of a similar nature, Gard et al. [26] observed viremia by Day 6 and seroconversion by Day 15 of heifers after intrauterine inoculation of BVDV
concurrent with transfer of embryos. Presence of the virus at high concentrations in the reproductive tract of transiently and persistently infected cows was reported previously
[27–30].