Efficacy of Enzootic Bovine Leukosis eradication in large farm systems [Polish]

摘要

The aim of the study was to establish the most effective way of eradicating Enzootic Bovine Leukosis in a large dairy farm system. It examined one farm having a population of 486 cows housed in three byres and one heifer byre. The results of the study indicated that there were four times fewer positive ELISA test results between 1997-2002 compared to the period between 1992-1996. Consistently eliminating BLV positive animals from the herd as well as retaining the serologically negative calves on a milk-substitute feed proved to be very useful methods. All the animals on the farm were serologically examined in 2002 and gave negative results in ELISA (gp51) tests. After 10 years of regular serological testing and successively eliminating all positive-reacting animals, the farm attained BLV-free status. The study demonstrated that creating BLV-free herds out of those having a high rate of infection (above 30%) is a long and gradual process. BLV eradication from infected farms requires rapid elimination of positive animals and good cooperation between farmers and veterinary services.