OBJECTIVE

Between September, 2010, and August, 2011, a series of cases of jaundice of unknown origin in young calves was detected in a number of farms in Southern Germany. This paper describes the syndrome on the basis of 57 cases, and the approach taken to discover the cause.

METHODS

The clinical course of the disease is described in 19 patients. Using a case definition (calves aged 1-3 weeks, total serum bilirubin>> 20 µmol/l and/or serum glutamate dehydrogenase [GLDH] activity >50U/l and/or autopsy findings with striking liver pathology [jaundice, liver dystrophy, cirrhosis]), 36 farms were included in an epidemiological survey. In a feeding trial, two batches of a dietary supplement feed, previously used in diseased calves on farms, were fed at the dosage recommendations of the manufacturer to four clinically healthy calves over 5days. Four other calves served as controls. The calves were clinically monitored daily, and blood samples were investigated using clinical chemistry and haematology.

RESULTS

Clinical examination revealed behavioural alterations (weakness, tonic-clonic seizures and bawling just before death), recumbency, jaundice and discolouration of faeces. In less severe cases without clinical signs, there was an increase in serum bilirubin concentration and/or GLDH activity. In the epidemiological survey of affected farms, the feeding of a diet supplement feed was registered in 54 of 57 cases. The feeding of two batches of that diet supplement feed to four clinically healthy calves resulted in a significant (p<0.05) increase in bilirubin and lactate concentrations, as well as the GLDH activity in serum, but without serious impairment of the general condition, whereas in control calves, no comparable changes were observed.

CONCLUSIONS

The results of the epidemiological survey and the feeding trial suggest a causal involvement of a dietary supplement feed. The toxic principle is unknown.

CONCLUSIONS

Knowledge of the clinical picture and the probable feed-related context is important to detect this disease early. The suspected dietary supplement feed has been taken off the market, but with other products similar problems may arise.