LAUSR

Bovine viral leukosis (BVL) is a disease with a high morbidity and low mortality. There are reports of natural infection in some bovine species, but it has been little studied in buffaloes. In Colombia, buffalo production is growing rapidly, and, so far, there are no reports of the disease. The objective of this study was to characterize buffalo production in the coffee-growing region and to determine, by PCR, the prevalence of BVL in buffaloes, as well as its presence in humans, cattle, and sheep near the coffee-growing region. Blood samples from 140 buffaloes and 10 buffalo milk samples were collected, and so were 58 samples from bovines, 35 samples from sheep, and 9 samples from humans that had been in contact with buffaloes. Hematological analyses were performed. Subsequently, DNA was extracted for PCR evaluation. Production information was gathered, and the results were processed and analyzed using the R software. The majority of animals were Mediterranean breed females, with a birth weight of 33.39 kg, a weaning weight of 202.93 kg, a calving interval of 491.77 d, a time to peak of 67.26 d, and 381.59 L of milk (adjusted to 305 d at two teats). A prevalence of 33.6 % and of 3.4 %, respectively, was detected in buffaloes and in bovines; no milk, sheep or human samples were positive. No risk factors associated with the infection were found; neither were significant alterations of the blood count or factors of production. These results constitute the first molecular report of the bovine leucosis virus (BLV) in the Americas and one of the first in the world.