The role of infection with anaerobes C. novyi in sudden deaths of pigs

Sudden deaths have already been reported in pigs with pathological findings suggesting Clostridia involvement. The number of cases that were noted in the period of 1995-1998 in a herd of about 2000 sows, show ed a tendency to increase (from 2.5% up to 5.8%). In the post mortem examination performed on the intestine, liver; spleen and muscle samples, no anaerobic toxins wer e detected,,while the number of Clostridia cells was found to be the highes t in the liver (concentration from 3 x 10(4) to 2 x 10(6)/g). A total numbe r of 15 strains of C. novyi and 15 strains of C. perfringens were isolated from the internal organ samples (liver and spleen) taken from 5 dead pigs. Serological diagnostics was performed for 5 isolates of C. novyi (3 isolate d from the liver, 1 from the spleen and 1 from the muscles of 5 dead sows). Four isolates of C, novyi were identified as serotype B and one isolate as serotype A (none of them was lethal alpha toxin producing strain). All C. perfringens serotypes were revealed to be defective in regard to their toxi nogenic properties (low alpha toxin concentration). The authors ruled out toxaemia as a possible cause of death of the animals. However, they suggested a possible accumulation in the liver of extremely easily sporulating C. novyi, possibly their multiplication in vivo or even to some extent their influence by means of lecitinase production which are C (toxin beta) and D (toxin gamma). Such toxins were able to extend their e ffect on the organism by causing the vascular disorders in the liver, and p erhaps in the spleen.