Horses that enter the country for sale or competition must be declared free of piroplasmosis. American horses that travel to foreign countries must be retested before they can return home. First, he says, the test can give false negative or positive readings, requiring additional tests for verification. Further, if one horse tests positive, other horses that came on the same plane may also need to be retested. Second, continues Knowles, the CFT uses infected horses to produce antigens.
Antigens are proteins in the parasites that cause horses to produce antibodies in their blood.
Although the new tests use the same antigens as the basis for detecting the parasites, Knowles' research team developed a method for producing them that doesn't require horses. Knowles works at the ARS Animal Disease Research Unit in Pullman, Washington. Then they developed new, more accurate tests using monoclonal antibody technology. ARS and WSU have applied for patents on the piroplasmosis tests. The NVSL is the U.S. laboratory that determines the piroplasmosis disease status of animals for import or export.