SEROEPIDEMIOLOGICAL STUDY ON DICTYOCAULUS-VIVIPARUS INFECTIONS IN 1ST YEAR GRAZING CATTLE IN NORTHERN GERMANY

In Lower Saxony, 103 of 258 (39.9%) first year grazing cattle herds were found to be serologically positive for antibodies against Dictyocaulus viviparus. Risk of infection was higher for cattle herds with an early turnout and a long grazing period, i.e. more than 150 days. Herds that were observed by the farmers at least once a day were less frequently seropositive than other herds. The early observation of clinical sips enables farmers to treat the animals in time and to prevent the spread of the disease. Supplementary feeding and prior grazing or mowing the pastures for hay or silage significantly reduced the risk of infection. Diagnosis of dictyocaulosis was done almost exclusively by the farmers on the basis of clinical symptoms with an accuracy of less than 50%. Anthelmintics were administered mainly as salvage treatments and not according to a strategic control regimen.