INVESTIGATIONS ON INFECTIOUS AGENTS FOR ABORTION AND STILLBIRTH IN SWINE IN SWITZERLAND

Fetuses and placentae of 171 cases of porcine abortion, stillbirth and mummification were examined for pathological lesions, bacterial infec tions and PPV (porcine parvovirus) infection. Furthermore IgG (immunog robulin G) levels were determined in fetal body fluids. Selected mater nal sera were tested for antibodies against Leptospira, Aujeszky's dis ease and hog cholera. PPV infection was diagnosed in 29.2 % of all cas es. Bacterial abortion was diagnosed in 8.2 %. Indications for an infe ctious agent were demonstrated in about 10 % of the cases. The etiolog y of the abortion could not be identified in 52 %. Inflammatory altera tions in association with the isolation of bacteria consisted of neutr ophilic infiltration and necrosis and were of particular value to diff erentiate bacterial contamination from infection. Infiltrations of mon onuclear leucocytes in brain, leptomeninx, kidney or myocard were obse rved in about 50 % of the fetuses with PPV infection. IgG levels were consistently elevated in fetuses serologically positive for PPV, bur: also in two fetuses, where no infectious agent could be identified.