An investigation into the mechanism of placental damage in rats inoculated with Salmonella dublin.

Rats were inoculated with viable Salmonella dublin organisms, or a crude S dublin endotoxin, at the fourteenth and nineteenth days of pregnancy. They were killed at intervals up to 96 hours after inoculation, and the pathogenesis of the lesions was compared. At each stage of pregnancy the initial lesions produced by live bacteria and crude endotoxin showed important similarities, confirming the significance of endotoxin in the pathogenesis of placental damage. There were differences in the later stages of the pathogenic process. Comparisons of the process of placental damage at the two stages of pregnancy have suggested that the same mechanism acts throughout the last third of pregnancy and that thrombosis and disseminated intravascular coagulation are not an important part of the mechanism of placental damage.