Deer can become infected with anaplasmosis, but surveys show that the prevalence is very low. Researchers do not feel infected deer are an important reservoir of infection for cattle. In most cases, outbreaks of disease are due to purchase of infected carrier cattle. The disease may not manifest itself for several years, depending on vector transmission by biting flies, other insects, or accidental transmission by man. Transmission from infected to nearby susceptible herds by biting flies or other vectors also is possible.
Cattle showing clinical signs usually respond to high dosages of oxytetracycline given by injection.
These cattle may die in spite of treatment because the tetracyclines only prevent spread of the organisms between red blood cells. They do not kill the organism once it is inside the cell. Early recognition and treatment is important. Blood transfusion of cattle with severe anemia may be helpful if practical under field conditions. Supportive treatment with fluids and electrolytes is helpful.