Tracking a new type of tick

The invasive longhorned tick is a new pest that could plague livestock producers in MFA territory.Just as cattle begin grazing green pastures again, University of Missouri researchers are tracking the invasive longhorned tick, which can cause weight loss, aborted pregnancies and even death in cattle.

Researchers from the MU College of Veterinary Medi­cine found the tick in a Linn County pasture in August 2022. The finding marks the northernmost appearance of the invasive pest in Missouri. It also appeared in June 2021 near Springfield.

Found in 17 states since 2017, the longhorned tick is a significant concern for cattle producers, says Rosalie Ierardi, anatomic pathologist at the MU Veterinary Medical Diagnostic Laboratory. Hundreds of ticks can attach to a single animal, causing irritation and significant blood loss.

Ierardi says tick infestations can spread quickly. Fe­males produce up to 2,000 eggs at a time. Since they can reproduce without mating with males, a single female can introduce a population of ticks into a new area.

The biggest reason veterinarians are concerned about this tick is that it transmits a cattle parasite that destroys red blood cells. Symptoms include jaundice, weakness and spontaneous abortions. The symptoms closely resemble those of bovine anaplasmosis, which is widespread in Mis­souri. A blood test is needed to tell the two diseases apart.

“Currently, there is no approved treatment,” Ierardi said. “Management typically focuses on reducing tick numbers and minimizing the impact of stress and other health issues that may affect a cow’s ability to mount a strong immune response.”

Producers can reduce risk by keeping cattle away from wooded areas and other habitats where ticks live and clearing weeds and brush regularly. Consider inspecting cattle for ticks during handling activities and when there are new introductions to the farm.

Native to Korea, China, Japan and eastern Russia, the longhorned tick has been well established as an invasive species in Australia and New Zealand since the 1950s. It is expected to continue to spread within North America in the coming years. Like other ticks, the longhorned tick can easily travel unnoticed on livestock, humans, pets and wildlife.

If you think you may have found an invasive tick, contact your local veterinarian, Extension specialist or health department for assis­tance to have the tick identified.