This fall I have had a few calls about anaplasmosis. This is a disease of cattle that is caused by a ricketsia bacterium. This bacteria is transmitted to cattle by ticks, blood sucking insects and iatrogenic. Iatrogenic transmission is where we use needles and undisinfected instruments on animals. The bacterium is picked up from use on one animal and then the instrument is used on another animal giving the disease to the next animal.
Clinical signs of this disease are weak, unthrifty animals. The animals will look pale and/or jaundice (a yellow color about their mucous membranes). When a small blood sample is taken, the sample will look more like Kool-Aid rather than blood. With this sample a complete blood count or CBC can be run, showing the anemia and red cell destruction. You can also send the sample in for an anaplaz test at a lab. You can also do a blood smear and if the infection is bad enough you can see the anaplaz on the red cells under 1,000 times magnification with a good microscope. Another diagnostic test would be a liver and/or spleen biopsy if the animal is dead.
Treatment of this disease is with tetracycline. But, the animal must be on tetracycline for 14 to 15 days straight at a level of 9 mg per pound of body weight. This type of therapy normally will clear the bacterium for the animal. If you treat for any amount of time less, you will cause a carrier animal that can transmit this disease to the rest of your herd. If you have a dairy, we may want to treat for only 3 to 4 days and then wait till dry off for the 14 to 15 day treatment.
Prevention of this disease means controlling insects. For the iatrogenic transmission it means adhering to aseptic technique. This means disinfecting items such as dehorners, knives for castration between animals and changing needles for vaccinations and de-worming. By Beef Quality Assurance it is recommended that needles are changed every 10 head. This will allow only the chance for 10 head or less to become infected from needle transmission. It also really helps by having a sharp needle for administration of vaccines.
Some people also propose feeding tetracycline all summer long. Besides the expense, we are subjecting the animals and bacteria to a drug at a low dose. This could cause resistant bacteria and so called super bugs that are resistant to this class of pharmaceuticals. This is the last thing we all want. And the public is watching agriculture very closely and looking for just this type of treatment. We really do not want to give them any fuel for their agenda.
Dr. Tim E. O’Neill, DVM, owns Country Veterinary Service in Farmington, Ark.
