Acta Morphologica 12. Supplementum (1963)
Proceedings of the annuel meeting of Hungarian Pathologists and Anatomists. Budapest, 1962
a) Experimental shigelloses induced enterally Extensive pathological investigations have revealed that for the induction of dysenteric intestinal changes the best model is the monkey, followed by bear cubs and cats. In other animals only elements of the dysenteric process could be reproduced. Summing up the results and evaluating the perspectives of work with the monkey as a model, highly important epidemiological, immunological and therapeutic results have been reached. Yet, monkeys are expensive and this is a serious obstacle, because large numbers of animals have to be killed in the various stages of infection if we want to study the experimental morphogenesis of the disease. The same applies to bear cubs. By the end of the past century attempts were made to induce dysenteric infection in cats; then for a long time no such reports appeared in the literature and it was only quite recently that a series of reports confirmed that shigellosis can in fact be inducedin cats by oral infection. However, theevidence presented makes it clear that enteral infection with shigellae did not always lead to the development of a true infectious disease. In recent times the following additional factors have been introduced into the work concerned with the enteral infection with shigellae of cats. 1. The functional state of the nervous system was influenced by pretreatment with certain drugs. 2. By introducing orally large amounts of Proteus, or pathogenic staphylococci, or by feeding deficient diets, the intestinal flora of the experimental animals was altered. 3. The animals were orally sensitized in advance with filtrates, lysates or vaccines of Shigella sonnei. These investigations are significant, because they involved large numbers of animals and besides recording the clinical changes bacteriological and histological studies were also made. Unfortunately, the histological changes have been described, most briefly, and the value of the histological evidence presented has been reduced by the fact that most of the specimens originated from animals that had succumbed to the disease. Experimental shigellosis of cats could be induced by the repeated administration of small numbers of shigellae, whereas no disease was produced if these doses had been given at once. There is scarce evidence in the literature of successful infections in the dog. In the rabbit some authors observed diseases similar to dysentery following infection with enormous doses of shigellae. When different methods were employed to reduce systemic resistance, for example fasting, neutralization of gastric acid, paralysis of intestinal