ABSTRACT
Industrial cattle-breeding in Bulgaria is characterized by large cattle-breeding complexes holding 500, 1,000 or 2,000 dairy cows; farms specialized in rearing calves for breeding purposes, and calves fattening units holding 2,000, 5,000 or 10,000 animals. A specific technology has been introduced for management purposes. This high concentration and specialization creates specific organisational problems for antiepizootic control measures. Bovine leucosis has been brought from abroad by imported breedings animals. A complex system for leucosis prophylaxis and control is obligatorily implemented. It is supervized and financed by the state. Particular care is taken of ensuring protective measures for import breeding animals. The infected farms are put under strict quarantine. The animals which show a positive reaction during complex diagnostic tests are slaughtered and the meat is used after heat-processing. The milk is heat-processed too and sent for further utilization. Calves born in infected farms are not fit for breeding purposes but for fattening only.