[Echinococcus multilocularis in Grisons: distribution in foxes and presence of potential intermediate hosts]. / Echinococcus multilocularis in Graubünden: Verbreitung bei Füchsen und Vorkommen potentieller Zwischenwirte.

The southern border of the European endemic area of Echinococcus multilocularis runs along the alpine crest. This endemic transition area was analysed in the canton Grisons on a small spatial scale. A total of 543 foxes originating from 10 areas north and 4 areas south of the main alpine divide were investigated. Parasites were isolated using the sedimentation and counting technique on intestinal contents. The mean prevalence of E. multilocularis was 6.4% with significant differences between different areas. In the southern valleys, only foxes from the Val Müstair were infected (14.3%). On the northern side of the main alpine divide, prevalences varied between 0 and 40%. The predation habits of foxes on potential intermediate hosts was investigated by means of stomach content analyses (n=530). Rodents of the genera Microtus/Pitymys were found in 19.6% of fox stomachs, Clethrionomys glareolus in 8.0% and Arvicola terrestris in 0.4%. A small scale analysis based on a 10 x 10 km grid suggested that the predation rate on the genera Microtus/Pitymys significantly correlated with the prevalence of E. multilocularis in foxes (Spearman's r = 0.51). Hence, E. multilocularis appears to occur in the alpine study area on a very small spatial scale. These local sources of infection may persist for decades. This may partly explains why, during the last 34 years, some human cases of alveolar echinococcosis occurred in areas of the Canton Grisons where the parasite is presently endemic in foxes. No such human cases have been recorded in other areas free of E. multilocularis.

[Enzootic calcinosis in 16 cows from 6 dairy farms in Unterengadin]. / Enzootische Kalzinose bei 16 Kühen aus 6 Milchviehbetrieben im Unterengadin.

Enzootic calcinosis was diagnosed in 16 cows, which originated from 6 dairy farms located in the Unterengadin valley in Switzerland between 1,402 and 1,650 metres above sea level. During the winter, the cows were fed haylage, which contained up to 50 per cent golden oat-grass (Trisetum flavescens), and hay and grain. The first symptoms of enzootic calcinosis were noted in March 1998, when some of the cows developed locomotor abnormalities. Additional cases were diagnosed during the following three months. The most important clinical findings were decreased milk production, weight loss, frequent recumbency, difficulty in rising, kneeling while rising and feeding, stilted gait, arched back, shifting weight from one foot to another and reluctance to remain standing after being roused. Of the 16 cows, 5 had elevated concentrations of serum calcium and 10 had decreased concentrations of serum magnesium. All cows had normal or decreased concentrations of serum phosphorus, because the feeding of haylage containing golden oat-grass had been discontinued two months previously. In all of the cows, the most important postmortem findings were severe calcification of the aorta, iliac artery, brachiocephalic trunk and pulmonary artery.