Seroprevalencia de infección por el virus de leucosis bovina durante 2015 en rodeos de cría de la Zona Deprimida del Río Salado, provincia de Buenos Aires, Argentina

Enzootic bovine leukemia (EBL) is a chronic, lymphoproliferative and highly contagious disease caused by the bovine leukemia virus (BLV). Blood is an important source of infection in veterinary practice; only 5 microliters are enough to infect a cow experimentally. The Zona Deprimida del Rio Salado (ZDRS) is the main region of breeding calves in Argentina, covering more than 6 million hectares with 16 % and 34 % of the national and provincial calf stock, respectively. The latest reports of ELB prevalence in cow-calf farms in Buenos Aires province were performed more than 20 years ago with values lower than 2 %. In this work, 1957 bovines from 90 cow-calf farms representing just over 85 % of the ZDRS were sampled to determine the presence of antibodies against BLV by agar gel immunodiffusion, a test used extensively in epidemiological studies, control and eradication of the disease. The prevalence in cow-calf farms was 6.6 % while the individual prevalence was 0.36 %. Since ZDRS is the main area of breeder calfs production in Argentina, it is relevant to determine EBLprevalence in this region in order to detect EBL free zones.