Aim: This study aimed to elucidate the ability of the bovine leukemia virus (BLV) to integrate into cells of heterologous organisms, in particular, Wistar rats, and examine the manifestations of the pathological process that could be seen in them.

Materials and Methods: Wistar rats - were divided into three groups. The first group (I) was fed milk of intact cows, the second (II) - milk of BLV-infected cows, and the third (III) - milk of cows, clinically BLV sick. Rats of all groups were divided into two subgroups: In the subgroup "a", there were adult rats, and in the subgroup "b", their offspring were included. At 3, 6, 9, and 12 months from the start of the experiment, the animals' blood of each group was examined by polymerase chain reaction (PCR) and enzyme-linked immunosorbent assay for the presence of BLV provirus and specific anti-leukemia antibodies. A general and biochemical blood test was performed; pathological changes in the internal organs were recorded.

Results: Using the PCR, the BLV infection was established in all experimental rats, whose immune response was expressed in varying degrees. At the initial stage of the infection, offspring rats were born healthy. The rats of the control groups Ia and Ib were intact to the BLV throughout the experiment. The biochemical blood tests have shown several signs of intoxication, endocrine disorders, and development of malignant processes in the experimental animals. There are also signs of liver, kidney, and myocardial damages, regardless of whether milk is infected or the cows are clinically leukemic. By the time, the experimental rats developed persistent thrombocytosis with an increase in the average volume of the blood platelets, which may be evidence of the leukemia infection by the megakaryocytic type. The most pronounced character of the change was in the offspring generation.

Conclusion: Wistar rats can be considered as a suitable laboratory model to study the BLV pathogenesis. Rats are not BLV natural host, however, they developed the pathognomonic BLV infection symptoms when they were fed infected and leukemic cow's milk.

Keywords: cattle, danger to humans, hematobiochemical indicators, leukemia, Wistar rats.

1. Polat, M., Takeshima, S.N. and Aida, Y. (2017) Epidemiology and genetic diversity of Bovine leukemia virus. Virol. J., 14(1): 209. [Crossref]

2. Kozyreva, N.G. and Gulyukin, M.I. (2017) Distribution of cattle leukemia and genetic variants of the pathogen on the territory of cattle-breeding farms of the central federal district of the Russian Federation. Kuban Vet. Med., 6: 4-9.

3. The Epizootic Review of the Range of Infectious and Specially Dangerous Animal Diseases in the Russian Federation. (2017) Available from: http://www.depvet.samregion.ru/assets/files/doklad.pdf. Last accessed on 11-04-2018.

4. Zakirova, Z.R. (2015) Geno-identification of the virus of Bovine leukemia. Cand. Vet. Sci., 8: 167.

5. Smirnov, P.N. (2015) The ideal model of the leukemia process development in the cattle: On the basis of own research. Issues Norm. Leg. Regul. Vet. Med., 2: 80-82.

6. Buehring, G.C., Shen, H., Schwartz, D.A. and Lawson, J.S. (2017) Bovine leukemia virus linked to breast cancer in Australian women and identified before breast cancer development. PLoS One, 12(6): e0179367. [Crossref]

7. Giovanna, M., Ulloa, J.C., Uribe, A.M. and Guitierrrez, M.F. (2013) Bovine leukemia virus gene segment detected in human breast tissue. Open J. Med. Micro., 3(1): 84-90. [Crossref]

8. Buehring, G.C., Shen, H.M., Jensen, H.M., Choi, Y., Sun, D. and Nuovo, G. (2014) Bovine leukemia virus DNA in human breast tissue. Emerg. Inf. Dis., 20(5): 772-782. [Crossref] [PubMed] [PMC]

9. Buehring, G.C., Shen, H.M., Jensen, H.M., Jin, D.L., Hudes, M. and Block, G. (2015) Exposure to Bovine leukemia virus is associated with breast cancer: A case-control study. PLoS One, 10(9): e0134304. [Crossref]

10. Robinson, L.A., Jaing, C.J., Campbell, C.P., Magliocco, A., Thissen, J.B and Antonia, S. (2016) Molecular evidence of viral DNA in non-small cell lung cancer and non-neoplastic lung. Br. J. Can., 115(4): 497-504. [Crossref] [PubMed] [PMC]

11. Zhang, R., Jiang, J., Sun, W., Zhang, J., Huang, K., Gu, X., Yang, Y., Xu, X., Shi, Y. and Wang, C. (2016) Lack of association between Bovine leukemia virus and breast cancer in Chinese patients. Breast Cancer Res., 18(1): 101. [Crossref]

12. Martinez, C.L., Lendez, P.A., Nieto, F.M.V., Dolcini, G.L. and Ceriani, M.C. (2018) Can Bovine leukemia virus be related to human breast cancer? A review of the evidence. J. Mammary Gland Biol. Neoplasia, 23(3): 101-107. [Crossref] [PubMed]

13. Mustafayev, A.R. and Bekshokov, K.S. (2014) To the issue of the specificity barriers of the Bovine leukemia virus in the experiment with white rats of the Wistar line. Bull. Dagestan State Univ., 1 Tom 132: 135-138.

14. Krasnikova, E.S., Larionova, O.S., Krasnikov, A.V., Utanova, G.K. and Belyakova, A.S. (2015) Diagnostic System for DNA Detection of Leukemia Virus and the Cattle Immunodeficiency by Multiplex Polymerase Chain Reaction. Patent No. 2615465. Russian Federation. MIIK C12N15/49, C12Q1/68. The Applicant and the Patent Owner is the FGBEU SGAU. No. 2115132112/10.

15. Kozyreva, N.G., Ivanova, L.A., Stepanova, T.V. and Gulyukin, M.I. (2017) Alimentary transmission of the Bovine leukemia virus. Inf. Dis., 15(S1): 128-129.

16. Smirnov, P.N., Khramtsov, V.V. and Garmatarova, T.V. (2016) The antibodies' nature to the BLV antigen by their belonging to a certain class of immunoglobulins. Bull. NSAU, 39(2): 91-96.

17. Makarov, V.G. and Makarova, M.N. (2013) Physiological, Biochemical and Biometric Indicators of the Norm of Experimental Animals. Guideline. SPB, Publishing House LEMA. p116.

18. Clinical Recommendations for the Diagnosis and Therapy of Ph-negative Myeloproliferative Diseases. (2014) (True Polycythemia, Essential Thrombocythemia, Primary Myelofibrosis). Under the Guidance of the Academic V.G. Savchenko. Recommendations Approved at the II Congress of Hematology in Russia. p81.

19. Donnik, I.M., Trofimov, O.V. and Pak, I.V. (2016) Search of leukemic markers in the cattle based on the cytogenetic studies. Kuban Vet. Med., 1: 11-13.

20. Smirnov, P.N. (2016) Chrono biological studies of the pathological process in ruminant leukemia. Innov. Food Secur., 14(4): 7-14.

21. Rozhkov, O.A., Borovoi, V.I., Smirnov, P.N., Trostyanskiy, I.V. Murtaza, G. (2016) Influence of the fulvic acid concentrate on the morphobiochemical blood indicators of BLV-infected cattle. Innov. Food Secur., 12(2): 5-10.

22. Pavlova, A.I., Smirnov, P.N., Koryakina, L.P., Garmatarova, T.V., Saksena, N. and Joyce, J.G. (2017) Comparative indicators of T and B-lymphocytes, immunoglobulins of the main classes and circulating immune complexes (CIC) in BLV infected and opportunistic microflora of cows. Innov. Food Saf., 15(1): 17-21.

23. Ermolin, A.E. (2002) The state of the pituitary-gonadal system in men with acute leukemia. Author's abstract. Dis. Cand. Med. Sci., 24.

24. Smirnov, P.N., Khramtsov, V.V., Mager, S.N., Razumovskaya, V.V. and Khavinson, V. (2017) The Immunomorphological changes accompanying the development of the human and animal hematological malignancies. Innov. Food Secur., 4(18): 39-50.