By Pet Talk staff
CNHI News Service
Fall's arrival means it's time for cattlemen to watch their herds for signs of anaplasmosis. This disease can be devastating if not treated properly or in a timely manner.
Anaplasma marginale is a parasitic organism transmitted through blood transfer by biting insects and ticks, or by surgical instruments such as needles. The organism attaches to red blood cells, which the body then removes, causing cattle to become anemic, explained Dr. Meredyth Jones, assistant professor at the Texas A&M College of Veterinary Medicine and Biomedical Sciences' Large Animal Hospital.
Anaplasmosis appears most often in the fall because symptoms surface 21 to 45 days after infection - typically after the busy biting fly season of late summer. Cattlemen in Southern states need to be particularly cautious because the disease appears most frequently south of Kansas.
“Many times cattle can be infected and show no signs of illness,” said Jones. “But during the fall months, if we are called on to examine a sickly, weak cow, anaplasmosis is high on our list of culprits.”
Cattle in the acute phase of infection may appear weak, “down" and generically sick due to anemia. Affected cattle may also exhibit white or yellow mucous membranes - such as eyes, muzzles, udders, and vulvas. These membranes will appear white due to a lack of red blood cells, or yellow because of the pigments released as red blood cells are broken down and removed from the body.
Some cattle may even exhibit signs of aggressiveness, a behavior caused by lack of oxygen to the brain.
Anaplasmosis may appear in a chronic form, caused by a moderate level of anemia. Affected cattle lose weight over time, which can cause abortions in pregnant cows. The blood of infected cows in both phases will be thin in consistency, almost watery, when examined.