Investigation of wasting among cattle

In this study, we reviewed the research that has been conducted in relation ship with the problem of 'chronic wasting' in dairy cows in the Netherlands as was experienced during 1998 and 1999. Emphasis was drawn towards three aspects of this 'chronic wasting'; the definition, the magnitude, and the p ossible cause or causes. It appeared that a clear, objective definition of 'chronic wasting' in cows, and of farms with a problem of 'chronic wasting' cows is still lacking. Furthermore, the incidence (of the problem) was res tricted to approximately 150 dairy farms at most. Currently, no farms with 'chronic wasting' cows are known. Combined with the uncertainty in the defi nition, this will hamper future research. Many of the studies were related to the hypothesis that the vaccination with the BHV1 marker vaccine had cau sed 'chronic wasting' in the cows. None of the results, however, substantia ted this hypothesis. Other possible causes have hardly been investigated an d further research would be needed to evaluate the role of nutrition, infec tious agents, and genetics. However, due to the wanting of the phenomenon, the availability of data and controls will be limiting.