Significance of potentially toxinogenic Clostridium spp. with regard to herd health problems in Bavarian dairy herds

摘要

In recent years, unusual herd health problems in dairy cattle herds were reported by veterinarians and farmers across Germany. Chronic suffering with severely decreased milk yield and significant losses were monitored and the involvement of botulinum-neurotoxin-producing Clostridia was assumed. To pursue this thesis, a clinical case-control study in dairy herds was carried out throughout Bavaria. It was based on a study conducted in Northern Germany by the University of Veterinary Medicine Hannover, Foundation, and the Friedrich-Loeffler-Institut. Herds in the case group (n = 21) had to meet at least three of the following criteria for the last year: markedly reduced milk yield &15%, animals euthanized/dead &5%, downer cows &10%, culling &35%, and/or an increased disease rate. In contrast control group herds (n = 10) were not allowed to meet any of these criteria. A total of 1720 dairy cows were included in the study, of which 142 case cows (signs of chronic disease) and 142 healthy control cows were subjected to a standardized clinical examination including bacteriological, parasitological and haematological testing.