Disease Alert

By Clay Coppedge
DTN/Progressive Farmer Contributing Editor

Last year, cattle producers learned again that anaplasmosis is a disease that can kill cattle. Cases of the blood disease spiked in areas where it had been a low-level concern and appeared in parts of the country where veterinarians hadn't seen it for years.

Cattle operations in parts of Kansas dealt with some of the highest anaplasmosis levels in the history of the state in 2015, reported Gregg Hanzlicek, who is with the Kansas State University college of veterinary medicine. While the disease had been endemic here for 100 years, the surge took it to every county in the eastern two-thirds of the state. Asked if the increase was due to ticks, a common spreader of anaplasmosis, or to the introduction of new cattle as operators try to grow herds, he said it's impossible to know.

Tom Hairgrove, veterinarian and livestock coordinator for Texas A&M AgriLife Extension College Station, stressed that while anaplasmosis may seem nonexistent at times, the dollars U.S. producers spend to manage and treat the condition are anything but invisible. Annually, researchers estimate the cost of anaplasmosis at about $300 million. A previously uninfected herd, once infected, will lose an estimated 3.6% of its calf crop to the disease. Cull rates in a newly infected herd can increase by 30%. Death loss in adults will average 30%

In all, 40 states reported the disease in 2015. It is most common in the Southeast, the Lower Plains, the West and the Gulf Coast. Hairgrove believes some of the recent rebounds in infection numbers have been due to lingering effects from drought, which caused cattle to be moved around more as a result spreading anaplasmosis.

"Producers destocked during the long droughts and repopulated when the droughts broke. Anytime you commingle infected and uninfected cattle, you run a risk of anaplasmosis," he said.

REACTIONS VARY

Anaplasmosis spreads via infected blood and insects like biting flies and ticks are prime carriers. It takes three to five weeks of incubation before symptoms appear. Cattle infected when they are less than 2-years-old usually adapt, becoming carriers.

Older cattle infected for the first time are hardest hit. They often have serious symptoms that can include fever, erratic or aggressive behavior, yellowing of the whites of the eyes, pale gums, labored breathing and anemia. Many cattle survive the disease, but it can be fatal.

"It's not like the sky is falling," Hairgrove said. "It just means if you're bringing [new] cows into your herd, be careful. Don't transfer blood from one cow to the other through needles, ear tags or a surgical instrument. Always clean instruments and change needles."

A clinical case of anaplasmosis (where the animal is showing symptoms and requires treatment) costs a producer more than $400 per animal. Treatment, when opted for, generally includes injectable oxytetracycline. Blood transfusions may also help. The stress of treating an animal too far along with the disease can lead to its death, so treatment recommendations vary widely.

(VM/CZ)

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