Stringhalt outbreaks, distinct seasonal pattern and the ability of affected horses to recover spontaneously. This condition is characterised by the sudden exaggerated flexion of either one or both hocks. This form of stringhalt most commonly occurs in the summer and autumn while horses are out on pasture. Epidemics of Australian stringhalt are usually witnessed during drought or abnormally dry conditions. The long digital extensor muscle (usually in the hind limb) is the muscle that appears to be the most affected by this condition. The most severe muscle lesions have been found within the long and lateral digital extensors and lateral deep
Nervous system multicellular animals, but vary greatly in complexity. The only multicellular animals that have no nervous system at all are sponges, placozoans, and mesozoans, which have very simple body plans. The nervous systems of the radially symmetric organisms ctenophores (comb jellies) and cnidarians (which include anemones, hydras, corals and jellyfish) consist of a diffuse nerve net. All other animal species, with the exception of a few types of worm, have a nervous system containing a brain, a central cord (or two cords running in parallel), and nerves radiating from the brain and central cord. The size of the nervous system ranges