Porcine cytomegalovirus (PCMV) in early gestation.

Following intranasal exposure to PCMV at or within 48 h of coitus transplacental infection occurred in two groups of gilts. Five out of 22 embryos were infected in the first group but only 2 out of 63 in the second. A more rapid immune response as measured by circulating antibody was probably instrumental in abrogating infection in the second group. In the infected embryos the virus localized in leptomeningeal cells, hepatic sinusoidal cells, peritoneal macrophages, periosteal cells and occasional alveolar cells, but the placenta did not appear to be a primary site of viral replication.