Bovine anaplasmosis is a headache for cattle farmers, but Roman Ganta is working to provide some relief for both producers and cattle.

“Farmers want to have something to prevent this disease because it is devastating for cattle in terms of milk production, meat production and also the economy,” says Ganta, a curators’ distinguished professor and the McKee endowed professor in Mizzou’s College of Veterinary Medicine and a Bond Life Sciences Center researcher. “The disease is widespread in the U.S., and throughout the world, so there is definitely a need for a vaccine.”

The disease spreads mechanically, such as through biting flies or contaminated needles, and more commonly, biologically through infected ticks. “Our new vaccine protects against both,” Ganta adds.

Caused by a bacterium called Anaplasma marginale, the search for protection from the disease has been a long road. However, recent research is producing a new solution using innovative technology that could be available to farmers and ranchers within the next five years.

Results from lab

In the past, researchers made vaccines for bovine anaplasmosis using antigens collected from infected cattle. Unfortunately, Ganta says that they often didn’t work well and caused side effects as they included cattle proteins. These early products were eventually pulled from the market.

Related:Longhorned ticks cover more ground in Missouri

Ganta started researching a bovine anaplasmosis solution at Kansas State University. There, he and his team took a different approach by diving deep into the bacterium’s genetics.

They identified key genes that help Anaplasma marginale survive and cause disease. “Using molecular genetics, we deleted that piece so that the protein is no longer made,” Ganta explains. “When the protein is not made, the animals do not develop the same disease.”

The new modified version of the bacterium doesn’t cause the disease and can still prompt a strong immune response in cattle, offering protection. “It's a promising breakthrough that could make a real difference for ranchers,” Ganta adds.

There are still more miles ahead before the vaccine can hit the market and be in cattle producers’ hands.

Now working at the University of Missouri, Ganta pushes the vaccine forward, noting that extensive testing to ensure safety and effectiveness must take place across different cattle populations and environments.

The team, which includes a private-industry partner, is gearing up to meet the USDA’s strict approval requirements.

Struggles of managing disease

In Missouri, most herds have at least one disease-positive animal, and about 45% of individual cattle have antibodies to Anaplasma marginale, says Rosalie Ierardi, who collects information regarding tick diseases at the MU Veterinary Medical Diagnostic Laboratory.

Related:Blood-sucking tick moves across cattle country

“This means they were infected in the past and are probably asymptomatic carriers,” she notes.

Targeting red blood cells, bovine anaplasmosis causes anemia. Cattle may show symptoms such as depression, fever, weight loss, difficulty breathing, and in some cases, the disease can be fatal, says Craig Payne, MU Extension beef veterinarian.

Once infected, animals become lifetime carriers of the bacteria, which can be positive and negative.

“The upside is that chronic carriers will likely never show clinical signs again, unless they become severely stressed or immunosuppressed,” Payne notes. “The downside is they are a source of the organism within a herd.”

Payne’s recommendation for most producers in Missouri: Don’t cull chronic carrier animals from the herd.

“If you replace them with animals that are free from anaplasmosis, you increase the number of animals that could succumb to the disease,” he explains.

Current control measures

Until this new vaccine comes to fruition in the marketplace, livestock owners can minimize the spread of bovine anaplasmosis through the following Animal and Plant Health Inspection Service and MU Extension recommendations:

Modify tick habitat. Keep grass cut short, and remove weeds and brush from grazing areas.

Restrict grazing areas. Keep cattle from grazing in wooded areas or heavily tick-infested pastures to reduce tick exposure.

Inspect regularly. Regularly inspect cattle for flies and ticks. Ticks can be especially found in the ears, under the tail area, between the hind legs and in udder skin folds.

Reduce fly habitat. Use sanitation practices such as cleaning out hutches, stalls, pens, feeding lanes and bunks on a regular basis; properly managing manure; and securing storage of feed.

Use insecticides. Regularly use EPA-approved products that kill ticks and flies on animals, vegetation and equipment.

Change equipment. Discard vaccination needles after use. Clean or disinfect blood-contaminated equipment used for dehorning, castration and tagging between animals.

Ganta remains optimistic that the prevention of bovine anaplasmosis is here.

“A few more regulatory tests and industry collaboration will bring our vaccine to farmers not only in Missouri,” he says, “but around the world.”

Leading the charge in tick research

Mizzou has been on the front lines of tick research for years.

A 2021 Mizzou study found recent increases in both the number and severity of tick-borne diseases in the Midwest, particularly in the humid climates of Missouri, Kansas, Oklahoma and Arkansas. The documentation of what, when and where ticks are present helps public health officials better understand the threat of tick-borne diseases to people, pets and livestock.

Researchers in Mizzou’s College of Veterinary Medicine and College of Health Sciences also were the first to identify the invasive long-horned tick in northern Missouri in 2022 and in Boone County in 2023.

Mizzou’s Veterinary Medical Diagnostic Laboratory assists livestock producers who notice various health problems in their cattle with tracking down the causes of such signs in an effort to support Missouri’s agriculture industry.