• 1. Ott SL, Johnson R, Wells SJ. Association between bovine-leukosis virus seroprevalence and herd-level productivity on US dairy farms. Prev Vet Med 2003;61:249262.

    • Search Google Scholar
    • Export Citation
  • 2. Bartlett PC, Sordillo LM, Byrem TM, et al. Options for the control of bovine leukemia virus in dairy cattle. J Am Vet Med Assoc 2014;244:914922.

    • Search Google Scholar
    • Export Citation
  • 3. Erskine RJ, Bartlett PC, Byrem TM, et al. Association between bovine leukemia virus, production, and population age in Michigan dairy herds. J Dairy Sci 2012;95:727734.

    • Search Google Scholar
    • Export Citation
  • 4. CABI International. Enzootic bovine leukosis. Available at: www.cabi.org/isc/datasheet/91714. Accessed Sep 26, 2017.

  • 5. USDA Food Safety and Inspection Service. Animal disposition reporting system. Cattle condemned postmortem in USDA inspected establishments. Period: fiscal year 2002. Available at: www.fsis.usda.gov/OPHS/adrsdata/2002/pmctfy02.htm?redirecthttp=true. Accessed Jun 15, 2017.

    • Search Google Scholar
    • Export Citation
  • 6. White TL, Moore DA. Reasons for whole carcass condemnations of cattle in the United States and implications for producer education and veterinary intervention. J Am Vet Med Assoc 2009;235:937941.

    • Search Google Scholar
    • Export Citation
  • 7. USDA APHIS Veterinary Services. Bovine leukosis virus in US beef cattle. Available at: www.aphis.usda.gov/animal_health/nahms/beefcowcalf/downloads/beef97/Beef97_is_BLV.pdf. Accessed Jun 15, 2017.

    • Search Google Scholar
    • Export Citation
  • 8. Zalucha J, Grooms DL, Erskine RJ, et al. Bovine leukemia virus in Michigan beef bulls. Clin Theriogenol 2013;5:451458.

  • 9. Kohara J, Konnai S, Onuma M. Experimental transmission of bovine leukemia virus in cattle via rectal palpation. Jpn J Vet Res 2006;54:2530.

    • Search Google Scholar
    • Export Citation
  • 10. Divers TJ, Bartholomew RC, Galligan D, et al. Evidence for transmission of bovine leukemia virus by rectal palpation in a commercial dairy herd. Prev Vet Med 1995;23:133141.

    • Search Google Scholar
    • Export Citation
  • 11. Wentink GH, van Oirschot JT, Pelgrim W, et al. Experimental transmission of bovine leukosis virus by rectal palpation. Vet Rec 1993;132:135136.

    • Search Google Scholar
    • Export Citation
  • 12. Erskine RJ, Bartlett PC, Byrem TM, et al. Herd-level determinants of bovine leukaemia virus prevalence in dairy farms. J Dairy Res 2012;79:445450.

    • Search Google Scholar
    • Export Citation
  • 13. Yuan Y, Kitamura-Muramatsu Y, Saito S, et al. Detection of the BLV provirus from nasal secretion and saliva samples using BLV-CoCoMo-qPCR-2: comparison with blood samples from the same cattle. Virus Res 2015;210:248254.

    • Search Google Scholar
    • Export Citation
  • 14. Asadpour R, Jafari R. Detection of bovine leukosis provirus in blood and semen samples of bulls. Comp Clin Pathol 2012;21:187191.

  • 15. Jaworski JP, Porta NG, Gutierrez G, et al. Short communication: relationship between the level of bovine leukemia virus antibody and provirus in blood and milk of cows from a naturally infected herd. J Dairy Sci 2016;99:56295634.

    • Search Google Scholar
    • Export Citation
  • 16. Gutiérrez G, Alvarez I, Politzki R, et al. Natural progression of bovine leukemia virus infection in Argentinean dairy cattle. Vet Microbiol 2011;151:255263.

    • Search Google Scholar
    • Export Citation
  • 17. USDA National Animal Health Monitoring System. Dairy 2014: dairy cattle management practices in the United States. Available at: www.aphis.usda.gov/animal_health/nahms/dairy/downloads/dairy14/Dairy14_dr_PartI.pdf. Accessed Jun 16, 2017.

    • Search Google Scholar
    • Export Citation
  • 18. USDA National Animal Health Monitoring System. Dairy 2007. Part 1: reference of dairy cattle health and management practices in the United States, 2007. Available at: www.aphis.usda.gov/animal_health/nahms/dairy/downloads/dairy07/Dairy07_dr_PartI.pdf. Accessed Jun 16, 2017.

    • Search Google Scholar
    • Export Citation
  • 19. Monke DR. Noninfectivity of semen from bulls infected with bovine leukosis virus. J Am Vet Med Assoc 1986;188:823826.

  • 20. Dus Santos MJ, Trono K, Lager I, et al. Development of a PCR to diagnose BLV genome in frozen semen samples. Vet Microbiol 2007;119:1018.

    • Search Google Scholar
    • Export Citation
  • 21. Jimba M, Takeshima SN, Matoba K, et al. BLV-CoCoMo-qPCR: quantitation of bovine leukemia virus proviral load using the CoCoMo algorithm. Retrovirology 2010;7:91.

    • Search Google Scholar
    • Export Citation
  • 22. Jimba M, Takeshima SN, Murakami H, et al. BLV-CoCoMo-qPCR: a useful tool for evaluating bovine leukemia virus infection status. BMC Vet Res 2012;8:167.

    • Search Google Scholar
    • Export Citation
  • 23. Murakami K, Kobayashi S, Konishi M, et al. Nationwide survey of bovine leukemia virus infection among dairy and beef breeding cattle in Japan from 2009–2011. J Vet Med Sci 2013;75:11231126.

    • Search Google Scholar
    • Export Citation
  • 24. Sun WW, Lv W-F, Cong W, et al. Mycobacterium avium subspecies paratuberculosis and bovine leukemia virus seroprevalence and associated risk factors in commercial dairy and beef cattle in northern and northeastern China. Biomed Res Int 2015;2015:315173.

    • Search Google Scholar
    • Export Citation
  • 25. Polat M, Takeshima SN, Hosomichi K, et al. A new genotype of bovine leukemia virus in South America identified by NGS-based whole genome sequencing and molecular evolutionary genetic analysis. Retrovirology 2016;13:4.

    • Search Google Scholar
    • Export Citation
  • 26. Cobo ER, Corbeil LB, BonDurant RH. Immunity to infections in the lower genital tract of bulls. J Reprod Immunol 2011;89:5561.

  • 27. Kaja RW, Olson C. Non-infectivity of semen from bulls infected with bovine leukosis virus. Theriogenology 1982;18:107112.

  • 28. Choi KY, Monke D, Stott JL. Absence of bovine leukosis virus in semen of seropositive bulls. J Vet Diagn Invest 2002;14:403406.

  • 29. Alvarez I, Gutiérrez G, Gammella M, et al. Evaluation of total white blood cell count as a marker for proviral load of bovine leukemia virus in dairy cattle from herds with a high seroprevalence of antibodies against bovine leukemia virus. Am J Vet Res 2013;74:744749.

    • Search Google Scholar
    • Export Citation
  • 30. Juliarena MA, Gutierrez SE, Ceriani C. Determination of proviral load in bovine leukemia virus-infected cattle with and without lymphocytosis. Am J Vet Res 2007;68:12201225.

    • Search Google Scholar
    • Export Citation
  • 31. Frie MC, Coussens PM. Bovine leukemia virus: a major silent threat to proper immune responses in cattle. Vet Immunol Immunopathol 2015;163:103114.

    • Search Google Scholar
    • Export Citation
  • 32. Kettmann R, Cleuter Y, Mammerickx M, et al. Genomic integration of bovine leukemia provirus: comparison of persistent lymphocytosis with lymph node tumor form of enzootic. Proc Natl Acad Sci U S A 1980;77:25772581.

    • Search Google Scholar
    • Export Citation
  • 33. Juliarena MA, Barrios CN, Ceriani MC, et al. Hot topic: bovine leukemia virus (BLV)-infected cows with low proviral load are not a source of infection for BLV-free cattle. J Dairy Sci 2016;99:45864589.

    • Search Google Scholar
    • Export Citation
  • 34. Esteban EN, Poli M, Poiesz B, et al. Bovine leukemia virus (BLV), proposed control and eradication programs by marker assisted breeding of genetically resistant cattle. In: Rechi LJ, ed. Animal genetics. Hauppauge, NY: Nova Science Publishers Inc, 2009;107130.

    • Search Google Scholar
    • Export Citation

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Breeding bulls as a potential source of bovine leukemia virus transmission in beef herds

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  • 1 1Department of Large Animal Clinical Sciences, College of Veterinary Medicine, Michigan State University, East Lansing, MI 48823.
  • | 2 2Viral Infectious Diseases Unit, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.

Abstract

OBJECTIVE

To determine the prevalence of bovine leukemia virus (BLV) in beef bulls; evaluate the presence of BLV provirus DNA in blood, smegma, and semen samples; and analyze whether blood BLV proviral load was associated with differential blood cell counts.

DESIGN

Observational cross-sectional study.

ANIMALS

121 beef bulls ≥ 2 years old from 39 Michigan herds.

PROCEDURES

Blood, smegma, and semen samples were collected from each bull during a routine breeding soundness examination. An ELISA was used to detect serum anti-BLV antibodies. A coordination of common motifs-quantitative PCR assay was used to detect BLV provirus DNA in blood, smegma, and semen samples. Bulls with positive results on both the BLV serum ELISA and coordination of common motifs-quantitative PCR assay were considered infected with BLV.

RESULTS

19 of 39 (48.7%) herds and 54 of 121 (44.6%) bulls were infected with BLV. Provirus DNA was detected in the blood of all 54 and in smegma of 4 BLV-infected bulls but was not detected in any semen sample. Lymphocyte count was significantly greater in BLV-infected bulls than in uninfected bulls. The proportion of BLV-infected bulls with lymphocytosis (16/54 [29.6%]) was greater than the proportion of uninfected bulls with lymphocytosis (6/67 [9%]). Lymphocyte count was positively associated with BLV proviral load in BLV-infected bulls.

CONCLUSIONS AND CLINICAL RELEVANCE

Results indicated that almost half of beef bulls and herds were infected with BLV, and BLV provirus DNA was detected in the smegma of some BLV-infected bulls. Bulls may have an important role in BLV transmission in beef herds.

Contributor Notes

Dr. Grooms' present address is Office of the Dean, College of Veterinary Medicine, Iowa State University, Ames, IA 50011.

Address correspondence to Dr. Benitez (ojbr483@hotmail.com).