Genetic polymorphism of the bovine viral diarrhea viruses in big dairy farms in Siberia

Bovine viral diarrhea is a widespread disease in the Russian Federation and causes significant economic damage to dairy cattle, especially under intensive commercial farming. The seropositivity of livestock in various Russian regions reaches 65-100 %. The disease is caused by two different virus species, BVDV-1 and BVDV-2, of which the latter is considered more virulent. The persistently infected (PI) animals which are a constant endogenous source of the virus in the herd play a major role in maintaining the stationary trouble of the farms. Short-term sources of the pathogen are transitively infected (TI) animals in which disease proceeds in acute form. Genetic structure of viruses circulating in local livestock populations gives necessary information about the evolution, geography and pathways of the pathogen. However, studies on the genetic polymorphism of viruses in Russia are not enough. This paper is the first to report on a phylogenetic analysis of two types of viral diarrhea virus, isolated from animals of foreign and domestic origin with different clinical manifestations of the disease...