The effect of bovine leukemia virus on dairy cow longevity

Abstract

Highlights• Dairy cows were tested for BLV with an ELISA milk test and followed for survival.• BLV-positive cows had shortened lifespans compared with BLV-negative herdmates.• BLV ELISA results were not associated with producer-reported reasons for culling.

Assessment of Natural Transmission of Bovine Leukemia Virus in Dairies from Southern Chile

“…Epidemiologic studies on dairy cattle have demonstrated an association between BLV infection and decreased productive lifespan within herds [4,41,42], although others have not found this association [5,43]. Therefore, those findings should be further investigated in future studies for different cattle breeds, geographic areas, and management systems for animals with high vs. low proviral load.…”

Molecular frequency of bovine leukemia virus in Creole cattle of Eastern Colombia

“…This increase has been particularly notable in areas from Canada and Argentina, resulting in significant economic losses ( John et al, 2024 ; Porta et al, 2023 ). In the United States, approximately 47.1 % of dairy cattle are affected, and 90 % of US dairy herds harbor at least one infected animal ( Benitez et al, 2022 ; LaDronka et al, 2018 ). Recent studies conducted across six different regions in Colombia have revealed prevalences ranging from 14 to 85 % among cattle, with BLV infection present in 75–100 % of the dairy and beef herds ( Corredor-Figueroa et al, 2020 ).…”