As ataxia (Greek .: ataxia , disorder) are at horses called interference with normal movements and posture. The cause here is not diseases or injuries to the musculoskeletal system, but damage to the central nervous system . The damage can in turn take the form of excessive movements (symptom of the upper motor neuron ) or reduced responsiveness ( lower motor neuron ) of the limbs.
There are several possible causes that can be responsible for ataxia. There are basically three different types of ataxia.
The spinal ataxia is an injury to the spinal cord and damage to the sensitive neural pathways based. This can be caused, for example, by injuries in which bruises press on the spinal canal . Even fine cracks in the bone substance can later lead to arthritic changes in the vertebrae, which cause them to swell and thus injure the spinal cord. Subluxations in joints in the cervical spine area ( wobbler syndrome ) are observed as a very common problem . Improper feeding in young animals can also be the cause of later onset ataxia. To protein - and energy-containing feed leads to a too rapid growth. The slower growing soft tissues can later trigger the ataxia. Disorders of the blood supply to the spinal cord caused by fibro-cartilaginous embolism or thrombosis can also cause spinal ataxia.
The cerebellar ataxia is caused by damage in the cerebellum ( cerebellum triggered).
The latter two ataxias are mostly the result of a severe viral infection . The equine herpes virus (EHV-1) can be the trigger . An infection with bacteria such as Borrelia burgdorferi ( borreliosis ) can affect the brain as well as the spinal cord and thus lead to ataxia. Furthermore, parasites such as Strongyles , Sarcocystis neurona , Toxoplasma gondii and Neospora hughesi can break through the blood-brain barrier and spread in the brain. Serious head injuries or poisoning can also lead to ataxia.
Basically, the horse's movement sequence is disturbed, its movements appear uncoordinated. It is difficult or impossible to direct backwards, avoids steeply sloping terrain and has problems, trips or falls on uneven ground or in tight turns. When guiding it by the hand, it stumbles and looks like drunk. With ataxias in the area of the hindquarters, the tail can be moved like a rubber. Unlike a healthy horse, the horse does not offer any resistance.
Ataxia in humans
- Martin Furr and Stephen Reed: Equine Neurology . Wiley & Sons; Blackwell Publishers 2008, ISBN 9780813825199