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Answers for Anaplasmosis

Keep anaplasmosis levels down by controlling biting flies and ticks, and using clean needles and equipment.(DTN/Progressive Farmer image by Jim Patrico)


I had a cow die, and my vet thinks it was anaplaz. I have never heard of this and neither has anyone else I've asked. What can you tell me about this disease?


I don't know what area of the country you are in, but anaplaz, or anaplasmosis, is a common disease in many parts of the country, especially the Gulf Coast. And it seems to be expanding.

This is caused by a small blood parasite that can destroy red blood cells, causing anemia and, in time, death. It's transmitted by biting insects, especially ticks and horseflies. Humans can spread the disease through the use of contaminated needles and instruments used for castration or dehorning.

Anaplasmosis is usually only seen in cattle older than 2 and is most common in summer and fall. But I am now seeing it even during the winter months here in Alabama.

Clinical signs may include some or all of the following: fever, weakness, depression or aggression, decreased appetite, decreased milk production, abortion in cows, infertility in bulls and a yellow color to the gums or eyes. At subclinical levels, the disease can lower pregnancy rates and decrease weaning weights.

Clinical cases of anaplasmosis can be treated with long-acting oxytetracycline injections if caught early enough. In severe cases, however, even blood transfusions won't save many of these infected animals. Many die from the stress of handling and are best left alone. Some may recover in time.

If you only suspect anaplasmosis, have your veterinarian screen your herd with a simple blood test. If it is detected, he or she can work with you to decide the best treatment and prevention plan. This may involve oxytetracycline injections or a medicated feed or mineral, now only available with a Veterinary Feed Directive (VFD).

Animals that recover on their own, or after treatment, will often be carriers. They may look completely normal, but they can still infect other cattle. For this reason, it is an excellent idea to test any cattle coming into your herd.

Control biting flies and ticks as much as possible, and always use clean needles and equipment when working cattle. Feeding oxytetracycline at a level labeled for the "prevention of anaplasmosis" during the biting fly season may be indicated in some herds in some areas if your veterinarian approves. A vaccine is also available, and it may be cost effective in some situations, but it is not approved in all states.

Please take this disease seriously. There have been reports of up to a 50% death loss with severe outbreaks. The most common loss to this disease is unseen, however. It means fewer calves on the ground and lower weaning weights. So even if you don't lose a cow, you are still losing money.