Red Blood Cells in Llamas: What Can Go Wrong?
by Susan J. Tornquist. DVM College of Vet. Medicine Oregon State University

A shortage of red blood cells is called anemia. This is a condition that is seen in all species of animals and it can range from mile to severe. The effect of anemia on al animal may not be noticeable to an owner, but the clinical signs can range from mild exercise intolerance to marked depression and even death. As red blood cells carry oxygen to all the tissues of the body, the lack of oxygen experienced by anemic (animals) will negatively impact he health of all tissues eventually.

There are many causes of anemia including the obvious ones like blood loss due to trauma and less obvious causes such as kidney disease, various types of toxins, trace mineral deficiencies (iron and copper, for example), cancers and others. Although we can determine the underlying cause of anemia in many cases, it remains a mystery in other cases. Treatment of anemia is most often based on treating the underlying disease or condition. In the cases of anemia for which we can’t identify a cause, we have to treat symptomatically. That is, we may need to give blood transfusions, drugs that stimulate red blood cell production, or injections of iron, which is a crucial component in hemoglobin, the oxygen-carrying molecule in blood.

One of the newer approached to treating anemia is to use blood substitutes. These are made from hemoglobin that is processed in a way that preserves its oxygen-carrying capacity, but eliminates some of the blood components that can cause undesirable reactions. Blood substitutes have certain advantages over transfusion of real blood. Of course, there are also some disadvantages, with cost being one of those. Although blood substitutes have been used occasionally in llamas and alpacas, their effects have not been tested in a controlled manner. We are hoping to study the effects of a blood substitute in camelids in order to provide veterinarians with some concrete information that can help them decide whether or not it is a “good option.”

One of the many causes of anemia in llamas is Mycoplasma haemolamae, a form of bacteria that attaches to red blood cells of llamas and alpacas. This organism was formerly known as Eperythrozoon spp. Infection with M. haemolamae (and) may cause a mild anemia that is not associated with any clinical signs, but on some animals, there is a severe anemia as the infected red blood cells are destroyed by the animal’s immune system. We have been studying M. haemolamae for several years and have developed a sensitive PCR assay that has been very helpful in diagnosis of this infection. We have used the assay to study the antibiotic treatment, oxytetracycline, which is most commonly used to treat the infection. We’ve found that, in many cases, treatment reduces the clinical signs of infection, but doesn’t totally eliminate the infection. This means that there are llamas that don’t show any signs of disease, but can serve as a source of infection for other animals. Our most recent study looked at the efficacy of another drug, florfenicol in treatment of M. haemolamae infection. Florfenicol is definitely not as effective as oxytetracycline and we would not recommend that it be used for this infection. There are some other drugs and treatment protocols that may be more effective in treatment and we are continuing to look for the best way to eliminate the infection. We are also continuing to study the prevalence and risk factors for M. haemolamae infection and are trying to determine how it is transmitted.

Red blood cells of camelids are among their very unique features. They have a different shape and properties than red blood cells of all other mammals. They’re crucial to an individual’s health and well being and they pose some interesting challenges for camelid veterinarians and researchers.

Reprinted from Llama Living the Michigan Lama Association NL, Vol. 10, Issue 2