Lyme disease is difficult to diagnose in horses, but it is a disease that horse owners should consider when a horse exhibits symptoms ranging from weakness, lameness, lack of appetite, and behavioral changes to kidney failure, heart disease or neurologic disorders. Treatment can be given as long as organ failure has not begun.
Many pet and horses owners do not see the ticks on their animals only to find out when tested these animals are indeed positive for Lyme disease.This infectious disease is caused by the bacteria Borrelia burgdorferi and affects horses, humans and many other animals. While fewer cases of Lyme disease are diagnosed in cold winter areas, it is a disease that both horse owners and veterinarians need to consider throughout the year.
Lyme disease in horses is quite common for animals living in high-risk areas where ticks are prevalent, but is not easy to identify, since fewer than 10% of horses show any symptoms and symptoms vary from horse to horse. An equine with Lyme disease may show an unexplained reluctance to move, as if sore all over, and/or a transitory lameness that cannot be ascribed to any specific cause. Joint swelling may also be apparent in some horses.
Veterinarians usually apply a process of elimination when investigating symptoms common to Lyme disease and other illnesses in horses.
Diagnosis in horses is further complicated by problems in detecting the spirochaetal bacteria Borrelia burgdorferi, which is responsible for Lyme disease, in blood samples taken from horses.
Blood tests, such as ELISA and Western blot, are carried out to check for antibodies to the bacteria, although the accuracy of these tests has been questioned, especially in cases of early Lyme disease where insufficient antibodies have built up to trigger detection.
A study published in July 2011 looked at antibody profiling for Borrelia in horses, with a focus on those living in the New England and Mid-Atlantic regions of the US where Infection with Borrelia burgdorferi is common.
The researchers used these animals to assess the efficacy of Luciferase Immunoprecipitation Systems (LIPS) for detecting antibody responses to three antigens used in diagnosing equine Lyme disease. Results of the tests strongly suggest that the LIPS test shows promise in improving detection of the disease.
Horses with Lyme disease may experience problems with multiple organ systems, leading to both acute problems and possible permanent damage and chronic health issues, especially where the infection remains untreated. Lyme disease complications in horses can include liver damage and hepatitis, or severe neurological injury from encephalitis, resulting in ataxia, and/or behavioral changes.