Embryo transfer as a means of controlling the transmission of viral infections. VII. The in vitro exposure of bovine and porcine embryos to foot-and-mouth disease virus

When 169 zona pellucida-intact bovine embryos were exposed to 10(6) pfu/ml of foot-and-mouth disease virus and then washed, no infectious virus was detected on any of the embryos. FMD viral infectivity was found, however, in association with 14 of 42 hatched (zona pellucida-free) bovine embryos and in a small number of zona pellucida-intact porcine embryos. The porcine embryos were assayed individually and in groups of 8 embryos. Four of the 124 individual embryos and 2 of the 9 groups of embryos carried the infectious virus.