A new genetics test that determines whether a stallion could be a persistent carrier of the equine arteritis virus has been developed by the University of Kentucky Gluck Equine Research Center.
Outbreaks of equine viral arteritis may result in significant economic losses to the equine industry because of pregnancy loss in mares, death in young foals, and cause longer-term problems through stallions that continue to carry the virus between breeding seasons, according to Gluck researchers.
The latest research completed at the Gluck Research Center by Drs. Udeni Balasuriya, Ernie Bailey, and Peter Timoney shows stallions identified with a “susceptible haplotype” (a group of four specific nucleotide changes in the CXCL16 gene) are more likely to retain the virus in their reproductive tracts than horses that possess the “resistant haplotype.”
Timoney stressed the test is a step toward identifying animals at risk for persistent infection, but it does not provide black-and-white answers. Some stallions carrying the resistant haplotype have still been found to be carriers.
The test does give stallion owners a clearer picture of their risk, which can be minimized through vaccination and appropriate management practices, according to Timoney.
“We have ample evidence that this vaccine conveys a very high level of protection,” Timoney said. “Even though the vaccine is a modified live strain, we have not confirmed yet a stallion that has become infected following the recommended treatment.”