1. Outbreak: since the late 10 years, an acute gastroenteritis among cows, chiefly of the Holstein cross breed, has been noticed ammo-nting to the loss of about 200 heads.
2. Course and Prognosis: 187 cases observed; severe cases take a peracute course and death occurs within 24 hours, acute cases die within a week, light cases may recover in 5 to 10 days. Mortality is about 43 percent.
3. Symptoms: 35 cases observed; high, quick and irregular pulses are marked terminating with acute course without exception, fever not marked, respiration quiet. Neither vomiting nor colic, appetite impaired, constipation, diarrhoea watery, mucous or mixed with dlood
4. Anatomical changes: 20 cadavers examined. Chiefly digestive canal and heart are affected. Jejunum, ileum and caecum are most noticeable, next the colon and stomach. Haemorrhage of m. m. necrosis, erosion or separation of epithelial layer and also haemo-rrhagic infiltration of submucosa. Heart with extensive haemorrhage, especially the auricles, apex, valves and other parts of epi-and endocardium, but not extending very deeply into the myofibre
5. Microscopical: Digestive apparatus; blood congestion, haemorrhage, round cell infiltration into mucous membrane, submucosa and muscle layer, degeneration necrosis and erosion of epithelial layer. Heart; blood accumulation in the loose connective tissue or superficially, but sometimes intrafibrial haemorrhage of heart muscle recognised by cloudiness and degeneration of myofibre.
6. Causal organism: by intravenous injection and feeding experiments with pure culture of B. paratyphus-B. type like bacillus isolated from the bloody mucous faeces of two cases, healthy test cattle become sick with symptoms and anatomical changes identical with those seen in natural infection. If the introduced bacilli are small in quantity the experimental infection is light and the animal 1105recovers, wiht larger quantity the animal developes a severe infection with marked symptoms and a fatal termination.
7. Mode of infection: Consideration suggested the food material called 'Tofukasu' which consists of ground raw bean. When this material was fully disinfected by hot steam the outbreak was brought to a standstills.
8. Conclusions: We have discussed systematically the haemorrhagical gastroenteritis of cattle outbreaks of which have occurred during the last ten years among the cattles of milkers causing much loss, we have isolated a special infectious agent which belong to the B. paratyphosus group and resembles its B. type, but which is not the same, finally we have brought the disease to a standstill by a simple practicable means.

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