Seropositivity and risk factors associated with the presentation of bovine leukosis virus in Sotaquirá, Colombia

BACKGROUND AND AIM: Enzootic bovine leukosis is a disease economically important to the dairy farming industry worldwide. The virus is of the Deltaretrovirus genus and is primarily transmitted iatrogenically. Most bovines infected with the virus remain asymptomatic with only 5-10% of cattle having lymphomas. This study aimed to determine the seroprevalence of bovine leukosis virus (BLV) in Sotaquirá, Boyacá, Colombia. MATERIALS AND METHODS: We conducted a descriptive, observational epidemiological cross-sectional study using the simple random sampling method with a sample size of 1000. Blood samples from random bovine were processed using the SERELISA(®) BLV Ab Mono Blocking indirect enzyme-linked immunosorbent assay kit (Zoetis, USA). The assay had a sensitivity of 97% and a specificity of 98%. The collected data were processed using Epi Info(®) (Centers for Disease Control and Prevention; Atlanta, Georgia). From the study, we could determine a high seroprevalence of BLV in Sotaquirá. RESULTS: We established a high seroprevalence on BLV in the municipality, with 31.1% apparent seroprevalence and 30.6% real seroprevalence rate. We found that male cattle more than 4 years old (39.4%) and the Ayrshire breed (45.5%) had the highest prevalence rates of the virus. In this study, we could establish statistically significant associations according to breed, age, and gender of the cattle under study. Moreover, we identified the risk factors for BLV infection. We found that in cattle aged <1 year and those older than 4 years of age and those of the Holstein breed, the presentation of infectious bovine rhinotracheitis, mucosal secretions, mastitis, fetal death, the presence of a corral, and the implementation of artificial insemination practices were risk factors for BLV infection. CONCLUSION: Determining the prevalence of BLV within the herd and identifying the associated risk factors for the disease are fundamental in developing efficient programs for the control and eradication of BLV within herds.