OSU scientists develop new test for anaplasmosis in livestock

By Alisa Boswell-Gore

STILLWATER, Okla. – Oklahoma State University scientists have developed a screening tool for anaplasmosis in livestock, which has the potential to save producers a lot of time and money.

The current industry standard for anaplasmosis detection in cattle, sheep and goats is the cELISA, a diagnostic tool that tells producers their livestock are infected with a disease. However, the test does not specifically indicate anaplasmosis, a bacterial disease transmitted through tick bites. This test costs $10 to $15 per blood sample due to an extensive process involving sending samples to a certified diagnostic laboratory.

“For most producers, it is just way too much money to test for this disease, so many of them end up losing 10 to 15 percent of their herd to it because they cannot afford to test them,” said Bruce Noden, associate professor and medical/veterinary entomologist in the OSU Department of Entomology and Plant Pathology.

According to Noden, what he and his colleagues have developed is a test strip, much like a pregnancy test, that is intended to act as a pre-screening tool for anaplasmosis.

“The point is to have a field test that a veterinarian can just drop a blood sample into and see if there are cases going on in the herd,” Noden said. “A producer uses this for screening, and if a sample is positive, they can send it off for cELISA confirmation. So, rather than having to test your whole herd with cELISA, you only have to test two or three cows. The whole point is trying to reduce the cost.”

Noden and Francisco Ochoa Corona, a professor of entomology and plant pathology and diagnostics specialist, said their screening process has been successful in showing livestock to be positive or negative for anaplasmosis, specifically in serum samples. The cELISA test detects a protein, but Noden and Corona’s screening process identifies the actual DNA of the anaplasmosis pathogen.

“The unique thing about this tool is that it is as specific as the polymerase chain reaction in detecting DNA without all the equipment, time or trained personnel needed to determine if a cow is positive for anaplasmosis,” said Justin Talley, professor and OSU Extension livestock entomologist.

“The cool thing about this diagnostic test is that it can test for the actual species and is more specific to how a veterinarian should care for the animals,” he added. “This test can differentiate between species of the Anaplasma genera, which allows treatment to be more precise.” 

Their research on the new screening test was published in Nature Scientific Reports in August, and the researchers submitted a patent for the screening test last year. Their second piece of OSU Ag Research, which highlights the method and success rate of the screening process, is being reviewed and will be published within the next few months.

Noden and Talley said the next step is to find an industry partner to further facilitate work on the diagnostic tool, so it can eventually be available to veterinarians working with food animal producers.

“Anytime you can make a veterinarian’s job easier, especially at the point-of-care, then it allows them to make decisions that help the producer before good cows die,” Talley said. “Oklahoma cattle producers are constantly dealing with anaplasmosis, and this disease targets animals that have a lot of investment from the producer. If a veterinarian can help assist those producers in a more specific and timely manner, it can limit the impact of this disease.”

OSU Ag Research is Oklahoma’s premier research and technology development agency in agriculture, natural resources and the life sciences.