Prevalence of Bovine Leukosis in the dairy basin of the province, Cercado de Trinidad, Beni.

Abstract

Introduction: This study determined the herd and farm prevalence of antibodies against the Bovine Leukosis virus in dairy cattle in the Cercado province of the Beni department. Method: Thirty dairies in four geographical areas were visited to study 390 heads of dairy cattle. Questionnaires and blood sampling were carried out at each dairy. Individual bovine sera were analyzed using the agar gel immunodiffusion (AGID) diagnostic method for the detection of antibodies against bovine leukosis virus, statistical comparison was performed using the Chi Square method, with a level of significance of 0.95 and an alpha value of 0.05. Results: The results obtained revealed a seroprevalence of 18.20% (95% CI: 14.25-22.16%) Zone V presented 23.07%, zone III 19.23%, zone VI 17.94%, and zone IV 15.38%. However, no significant statistical differences were observed between the studied areas (P<0.05), revealing a natural spread of the disease throughout the dairy basin. Regarding the prevalence by race, 20.79% was observed for the Creole race, 20.51% for Gyr Holando, 16.66% for Mestizas Holando, 18.64% for Brown Swiss, and 12.96% for Nelore. No significant statistical differences (P<0.05) were identified between breeds. The analysis by age groups revealed that cows 5 to 6 years old had the highest prevalence (21.21%), followed by those 6 to 7 years old (19.51%), those over 7 years old (16.66%), those 4 to 5 years old (12.50%), and those from 3 to 4 years without positives. Conclusion: These findings suggest a homogeneous distribution of bovine leukosis in the studied population, regardless of the origin of the cows.