Yersinia enterocolitica infection in goat. A serological and bacteriological investigation.

The distribution of agglutinating antibodies to Yersinia enterocolitica type 2 in sera from goats in an infected herd, and in 190 other animals from different parts of the country was studied. The faecal excretion of Yersinia enterocolitica from the same animals was also examined. Experimental inoculations of two goats were carried out. The serological results indicate that subclinical cases had occurred in the infected herd during the enzooty and during the following months. Faecal excretion of the organism was observed during the first month after the acute phase of the disease. It was found to be difficult to induce the disease experimentally, but clinical signs were observed in 1 goat after injection of live Yersinia enterocolitica intraperitoneally. The Widal-titre rose to 1/1250 during the first 2 weeks after the inoculation and then fell to 1/80 during the next 2 months. The serological results indicate infections with Yersinia enterocolitica, if a Widal-titre of at least 1/80–1/160 in the first month after the acute phase of a disease and a fall to a low level during the following months are found. Among animals from different partst of the country 16.3 % had a Widal-titre which indicated infection with Yersinia enterocolitica during the previous 3–6 months.