Original Scientific Article
Sero-prevalence of bovine leukemia virus infection in Kosovo cattle
Correspondence: Armend Cana, email@example.com
Received: 06 February 2020
Received in revised form: 10 September 2020
Accepted: 22 September 2020
Available Online First: 01 October 2020
Published on: 15 October 2020
A cross-sectional survey was conducted in Kosovo to determine the presence and prevalence of bovine leukemia virus antibodies in cattle. A total of 5,051 serum samples from 315 villages were collected during 2016. Samples were tested using commercial indirect enzyme-linked immunosorbent assay. At least one sero-positive animal was found in 55 (17.5%) of the villages sampled, of which 23 had more than one sero-positive detected. Overall individual sero-prevalence, corrected for geographic distribution of samples, was found to be 2.26% (95% c.i. 1.62% to 3.04%). There were no statistically significant associations between serological status and herd size or age of animal, although sero-prevalence in 5-year-old cattle was higher than in the other ages. There was a statistical significant heterogeneity in sero-prevalence between different geographic zones of Kosovo (chi‐square value = 20.68 (4 d.f.); (p=0.0004). Pairwise comparisons showed that sero‐prevalence in the south was significantly higher than in the east and in the north and sero‐prevalence in the west was significantly higher than in the north. The 3.11% aggregated sero-prevalence for the two highest sero-prevalence zones, south and west, was significantly higher than the 1.57% aggregated sero-prevalence for the remaining zones, centre, east and north (Fisher exact p‐value (2‐tail) = 0.0004). The reason for higher prevalence in the south and west of Kosovo is uncertain. These results may serve to enrich the information of bovine leukemia virus distribution in the region, as well as a starting point for the future control and eradication strategy in Kosovo.
Keywords: bovine leukemia virus, epidemiology, sero-prevalence, Kosovo
- Polat, M., Takeshima, Sh.N., Aida, Y. (2017). Epidemiology and genetic diversity of bovine leukemia virus. Virol J. 14(1): 209. https://doi.org/10.1186/s12985-017-0876-4 PMid:29096657 PMCid:PMC5669023
- Hopkins, S.G., Digiacomo, R.F. (1997). Natural transmission of bovine leukemia virus in dairy and beef cattle. Vet Clin North Am Food Anim Pract. 13(1): 107-128. https://doi.org/10.1016/S0749-0720(15)30367-4
- Panei, C.J., Larsen, A.E., Fuentealba, N.A., Metz, G.E., Echeverría, M.G., Galosi, C.M., Valera, A.R. (2019). Study of horn flies as vectors of bovine leukemia virus. Open Vet J. 9(1): 33-37. https://doi.org/10.4314/ovj.v9i1.6 PMid:31086763 PMCid:PMC6500860
- Kohara, J., Takeuchi, M., Hirano, Y., Sakurai, Y., Takahashi, T. (2018). Vector control efficacy of fly nets on preventing bovine leukemia virus transmission. J Vet Med Sci. 80(10): 1524-1527. https://doi.org/10.1292/jvms.18-0199 PMid:30122691 PMCid:PMC6207509
- Ruiz, V., Porta, N.G., Lomonaco, M., Trono, K., Alvarez, I. (2018). Bovine leukemia virus infection in neonatal calves. Risk factors and control measures. Front Vet Sci. 5, 267. https://doi.org/10.3389/fvets.2018.00267 PMid:30410920 PMCid:PMC6209627
- Nagy, D.W., Tyler, J.W., Kleiboeker, S.B. (2007). Decreased periparturient transmission of bovine leukosis virus in colostrum-fed calves. J Vet Intern Med. 21(5): 1104-1107. https://doi.org/10.1111/j.1939-1676.2007.tb03071.x PMid:17939571
- Nekouei, O., Vanleeuwen, J., Stryhn, H., Kelton, D., Keefe, G. (2016). Lifetime effects of infection with bovine leukemia virus on longevity and milk production of dairy cows. Prev Vet Med. 133, 1-9. https://doi.org/10.1016/j.prevetmed.2016.09.011 PMid:27720022
- Erskine, J.R., Bartlett, P.T., Byrem, T.M., Render, C.L., Febvey, C., Houseman, J.T. (2012). Association between bovine leukemia virus, production, and population age in Michigan dairy herds. J Dairy Sci. 95(2): 727-734. https://doi.org/10.3168/jds.2011-4760 PMid:22281337
- Pezler, K. D (1997). Economics of bovine leukemia virus infection. Vet Clin North Am Food Anim Pract. 13(1): 129-141. https://doi.org/10.1016/S0749-0720(15)30368-6
- Otto, S.L., Johnson, R., Wells, S.J. (2003). Association between bovine-leukosis virus seroprevalence and herd-level productivity on US dairy farms. Prev Vet Med. 61(4): 249-261. https://doi.org/10.1016/j.prevetmed.2003.08.003 PMid:14623410
- OIE. Manual of Diagnostic Tests and Vaccines for Terrestrial Animals. Vol. Chapter 3.4.9. 2019.
- Kuczewski, A., Orsel, K, Barkema, H.W., Kelton, D.F., Hutchins, W.A., Van Der Meer, F. (2018). Short communication: Evaluation of five different ELISA for the detection of bovine leukemia virus antibodies. J Dairy Sci. 101(3): 2433-2437. https://doi.org/10.3168/jds.2017-13626 PMid:29274963
- Sandev, N., Ilieva, D., Sizov, I., Rusenova, N., Iliev, E. (2006). Prevalence of enzootic bovine leukosis in the Republic of Bulgaria in 1997-2004. Vet Arhiv. 76(3): 263-268.
- Bennett, S., Woods, T., Liyanage, W.M., Smith, D.L. (1991). A simplified general method for cluster-sample surveys of health in developing countries. World Health Stat. Q. 44(3): 98-106.
- Commission of the European Communities: European Commission Decision of 15 December 2009 amending Annex D to Council Directive 64/432/EEC as regards the diagnostic tests for enzootic bovine leucosis (2009/976/EU)." Official Journal of the European Union 336 (n.d.): 36-41.
- Dean, A.G., Sullivan, K.M., Soe, M.M. OpenEpi: Open source epidemiologic statistics for public health. Version. Updated 2013. Available at: http://openepi.com/Menu/OE_Menu.htm.
- Wilson, E.B., (1927). Probable inference, the law of succession, and statistical inference. Journal of the American Statistical Association 22(158): 209-212. https://doi.org/10.1080/01621459.1927.10502953
- Rothman, K.J., Boice, J.D.Jr. (1979). Epidemiologic analysis with a programmable calculator. NIH Pub No. 79‐1649. Bethesda, MD: National Institutes of Health, pp. 31-32.
- Wallis, S. (2013). Binomial confidence intervals and contingency tests: mathematical fundamentals. JQL. 20(3): 178‐208. https://doi.org/10.1080/09296174.2013.799918
- Cannon, R.M., Roe, R.T. (1982). Livestock disease surveys. A field manual for veterinarians. National government publication. Bureau of rural science, Department of primary industry. Australian Government Publishing Service, Canberra, pp 14.
- Şevik, M., Avci, O., Ince, O.B. (2015). An 8-year longitudinal sero-epidemiological study of bovine leukaemia virus (BLV) infection in dairy cattle in Turkey and analysis of risk factors associated with BLV seropositivity. Trop Anim Health Prod. 47(4): 715-720. https://doi.org/10.1007/s11250-015-0783-x PMid:25708566
- Murakami, K., Kobayashi, S., Konishi, M., Yamamoto, T., Tsutsui, T. (2011). The recent prevalence of bovine leukemia virus (BLV) infection among Japanese cattle. Vet Microbiol. 148(1): 84-88. https://doi.org/10.1016/j.vetmic.2010.08.001 PMid:20832956
- Frie, M.C., Coussens, P.M. (2015). Bovine leukemia virus: A major silent threat to proper immune responses in cattle. Vet Immunol Immunopathol. 163(3-4): 103-114. https://doi.org/10.1016/j.vetimm.2014.11.014 PMid:25554478
- Wu, M.C., Shanks, R.D., Lewin, H.A. (1989). Milk and fat production in dairy cattle influenced by advanced subclinical bovine leukemia virus infection. Proc Natl Acad Sci. USA. 86(3): 993-996. https://doi.org/10.1073/pnas.86.3.993 PMid:2536940 PMCid:PMC286605
- Yang, Y., Fan, W., Mao, Y., Yang, Z., Lu, G., Zhang, R., Zhang, H., Szeto, C., Wang, C. (2016). Bovine leukemia virus infection in cattle of China: Association with reduced milk production and increased somatic cell score. J Dairy Sci. 99(5): 3688-3697. https://doi.org/10.3168/jds.2015-10580 PMid:26923050
- Oltenacu, P.A., Algers, B. (2005). Selection for increased production and the welfare of dairy cows: are new breeding goals needed? Ambio. 34(4-5): 311-315. https://doi.org/10.1579/0044-7447-34.4.311 PMid:16092261
- Ladronka, R.M., Ainsworth, S., Wilkins, M.J., Norby, B., Byrem, T.M., Bartlett, P.C. (2018). Prevalence of bovine leukemia virus antibodies in US dairy cattle. Vet Med Int. 4, 1-8 https://doi.org/10.1155/2018/5831278 PMid:30534354 PMCid:PMC6252197
© 2020 Gjinovci V. This is an open-access article published under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Conflict of Interest Statement
The authors have declared that no competing interests exist.
Macedonian Veterinary Review. Volume 43, Issue 2, Pages 175-183, e-ISSN 1857-7415, p-ISSN 1409-7621, DOI: 10.2478/macvetrev-2020-0030, 2020