Characteristics of the equine rhinopneumonia virus ak-2011

Equine rhinopneumonitis is an acute, highly contagious disease found virtually worldwide. The object of the studies was the AK-2011 strain isolated from the horses suffering from rhinopneumonitis during an outbreak of abortions. The viability of the AK-2011 strain was assessed using a continuous line of calf trachea cells, a continuous line of calf kidney cells, a continuous line of sheep kidney cells, a continuous line of bovine kidney cells, a continuous line of green monkey kidney cells, a continuous line of Syrian hamster kidney cells, a primary trypsinized culture of horse kidney cells grown in tubes and flasks, and the AK-2011 laboratory strain of equine rhinopneumonitis virus with biological activity of 6.0 lg TCID50/cm3. Sequencing and polymerase chain reaction (PCR) analysis were performed. The virus isolated from the ORF68 gene in Kazakhstan appeared to be the most similar to the T-953 and 2222-03 strains isolated in the USA and Australia, respectively, in terms of phylogenetics. As to primary infections, cytopathic effects (CPE) induced by the AK-2011 virus stain (dilution 101) in calf trachea and horse kidney cell cultures were stable from the 1st to 10th passages, with biological activity of 5.75-6.00 lg TCID50/cm3. CPE caused by the virus were apparent on days 2-3, further developed intensively, and extended to 60-80% of the cell monolayer on days 5-7. In calf kidney, sheep kidney, green monkey kidney, and bovine kidney cell cultures, the same changes were observed 1-2 days later. The changes were slow, and by day 7-10 CPE extended to no more than 30-50% of ​​the cell monolayer. An attenuated strain AK-2011 of equine rhinopneumonitis virus was obtained. It was considered a candidate for the manufacture of a vaccine for equine rhinopneumonitis. Thus, the attenuated strain AK-2011 of the equine rhinopneumonitis virus was characterized.