Affiliation:
1. Saku Livestock Hygiene Service Center of Nagano Prefecture Nagano Japan
Abstract
AbstractWe monitored the bovine leukaemia virus (BLV) proviral load (PVL) in peripheral blood lymphocytes (PBLs) and the PBL counts in BLV‐infected cattle on a dairy farm in Japan to determine the changes in PVL with the progression of lymphocytosis. A total of 25 BLV‐infected Holstein cattle at a dairy farm were followed up from May 2015 (0 month) to April 2016 (11 months). PBL counts and PVL were measured three times in 25 cattle. Based on their PBL counts, five cattle with normal PBL (≤7500 cells/µL) at 0 month but high PBL (>7500 cells/µL) at 11 months were classified as the increased group. All cattle in the increased group showed increased PVL compared to asymptomatic aleukaemic carriers at 11 months. This study revealed increases in PVL with the progression of lymphocytosis, suggesting that cattle with progression of lymphocytosis should be segregated from BLV‐negative cattle as soon as possible.
Reference25 articles.
1. Bovine leukaemia: Facts and hypotheses derived from the study of an infectious cancer
2. Bovine enzootic leukosis;Bendixen HJ;Adv Vet Sci,1965
3. Current Developments in the Epidemiology and Control of Enzootic Bovine Leukosis as Caused by Bovine Leukemia Virus
4. Relationship between lymphosarcoma and persistent lymphocytosis in cattle: a review;Ferrer JF;J Am Vet Med Assoc,1979
5. Role of insects in the transmission of bovine leukosis virus: potential for transmission by stable flies, horn flies, and tabanids;Buxton BA;Am J Vet Res,1985