PREVENTION OF ENZOOTIC BOVINE LEUKOSIS IS THE BASIS OF EPIZOOTIC WELL-BEING IN CATTLE BREEDING
One of the most important state tasks in the system of antiepizootic measures in cattle breeding of the Russian Federation is the improvement of dysfunctional farms for enzootic bovine leukosis. Since treatment and vaccination have not been developed for BLV, the only preventive measures of this viral disease are early diagnosis and prevention of enzootic bovine leukosis in the system of general and special veterinary and sanitary measures in farms of various forms of ownership. Despite the relatively high efficiency of modern methods of diagnosing the disease, there is a possibility of incomplete identification of animals infected with bovine leukemia virus in convalescent herds, which lengthens the duration of health programs and may be due to the influence of genetic variability of individual isolates of the virus. For the first time, as a result of the studies conducted in 2021-2022, the genetic variability of the bovine leukemia virus: presumably it is the Belgian genotype according to RFLP - was studied. Based on the data on the geographical distribution of bovine leukemia virus isolates in the Russian Federation, it was found that the genotype of the BLV - group G4 assimilates in Belgorod region. Thus, an improved system of health-improving antiepizootic measures for enzootic bovine leukosisshould be carried out depending on the level of infection of animals, taking into account the genetic variability of the pathogen, which will significantly accelerate the eradication of BLV in disadvantaged dairy farms of the Belgorod region. The method of early detection of leukemic animals in dysfunctional farms is based on a reduction in the frequency of the study from 6 months to 2-3 months and an increase in the concentration of antibodies to BLV in the studied blood serum samples at the stage of sample preparation of the serological reaction AGID. This is a new technological stage in the improvement of anti-leukemia measures in the Belgorod region, which can be successfully implemented only with the integration of state veterinary medicine, scientific organizations and direct cooperation with farms operating in the real sector of the economy, providing support for the implementation of innovative technological projects. The application of the developed methodological approaches made it possible in 2021 to completely improve the number of animals from leukemia infection the Belgorod region with an infection rate of up to 80% in previous years, and also to start improving other disadvantaged farms in the Belgorod region in 2022.