A little-known, potentially fatal cattle disease is being reported to Ohio veterinarians, indicating a need for producer education, a pair of Ohio State University Extension experts say.
Bovine anaplasmosis is a bloodborne disease that could cause severe anemia shortly after a cow is infected, which in some cases results in death or abortions, said William Shulaw, OSU Extension beef and sheep veterinarian. Cows that recover from the disease become a lifetime carrier of the bacteria that causes it, unless successfully treated.
To help producers learn more about the disease, OSU Extension and the Morgan County Soil and Water Conservation District are sponsoring a free workshop Dec. 11 at 7 p.m. in the Morgan High School cafeteria, 800 Raider Drive, 3.2 miles south of McConnelsville at state Route 376.
Bovine anaplasmosis is typically transmitted through biting flies and blood-contaminated inanimate objects such as hypodermic needles, some tagging instruments, surgical instruments, nose tongs, and possibly tattoo equipment, Shulaw said.
Although there is a disease called “anaplasmosis” in human beings, it is not the same, and the disease in cows is not transmitted to humans, he said.
“It’s a disease that’s been in Ohio for quite a while, with veterinarians reporting several cases each year, yet many producers don’t know about it,” Shulaw said. “Most cases are reported in the fall, which suggests that horseflies are a common vector for the disease in our region.
“Incubation is a few days to a couple of months, but it can occur any time of the year when the disease is transmitted.”
Chris Penrose, OSU Extension educator, said cattle producers need to understand how significant bovine anaplasmosis is for their herds.
“It’s out there and we want people to be aware of it and to know what to look for,” he said. “The goal is to educate people on how the disease spreads and know how to deal with it if any of your animals get it. We’ve had some cases in our area every year, and people want to learn more.”
Shulaw said animals that develop the clinical signs of anaplasmosis, typically starting with a fever of about 104 degrees or higher, are usually older than a year.
“The red blood count can fall very rapidly and animals can become severely anemic in just a few days,” he said. “As the anemia progresses, the animal gets weak, reduces or refuses feed intake, and becomes lethargic.”
Lack of oxygen to the animal’s brain resulting from anemia may cause it to act aggressively or behave abnormally, Shulaw said, noting that cows in advanced pregnancy may abort.
Treatment with injectable tetracycline will usually halt an outbreak in a herd and may prevent the development of severe anemia in an animal already incubating the disease, he said.
Penrose said that producers can suffer large herd losses while trying to get bovine anaplasmosis under control.
“It’s been around for a while but people are just now becoming aware of it even though it has caused some significant impact in some Ohio herds in recent years,” he said.
“Knowing what to look for is important because a well-explained death may be better than a poorly explained recovery. If we know why the animal died, we could potentially know how to prevent it in other animals.”