ECONOMIC AND PRODUCTION CONSEQUENCES OF LIVER FLUKE DISEASE IN DOUBLE-MUSCLED FATTENING CATTLE

The frequency of liver fluke disease in fattening units was determined by the analysis of random faeces samples issued from 1,513 Belgian White Blue aged from 5 to 7 months and weighing from 200 to 300 kg. 12.5% of the investigated bulls were positive for liver fluke disease. These bulls were spread over 56.5% of the investigated fattening units. Furthermore the infestation rate varied from 0 to 33.3% inside the fattening units. In order to assess the economic consequences of bovine fascioliasis in double-muscled cattle and the beneficial effects of a treatment against such a disease, a trial including 30 Belgian White Blue bulls, weighing 365 +/- 9 kg and aged from 10 to 12 months, was conducted in a selected fattening unit. On the basis of faecal examinations, the 30 animals were subdivided in negative (group A; n = 10) and positive animals (n = 20 for fascioliasis, the latter being either treated with nitroxinil (group B; n = 10) or not (group C; n = 10) on day 0 of this trial which was conducted during 75 days. The daily body gains in group C (1.661 +/- 0.140 kg) were significantly lower than those in group A (1.975 +/- 0.120 kg). On the other hand there was no significant difference between the daily body gains registered in group B (1.960 +/- 0.085 kg) and A. The estimated financial loss, due to flukes and accounted on a 75 day-period, averaged 2,748 Belgian Francs per bull in group C. Accounted on a similar period the treatment yielded a profit of about 2,617 Belgian Francs per bull. If we consider a fattening unit where bulls weigh 300 kg on average at their arrival and where the level of positive bulls for liver fluke disease reaches 10%, the treatment shows a profit 4.2 times greater than the cost of the treatment of all the animals arriving at the station during one year. We can conclude that the liver fluke disease induces a significant reduction of both performances and profitability, that these hidden effects are countered by nitroxinil treatment and finally that the treatment of each animal incorporated in fattening units, where liver disease has regularly been detected, is profitable.