Recovery of horses from dysautonomia (grass sickness)

The outcome for 35 horses with chronic dysautonomia which were kept in the hospital at the Royal (Dick) School of Veterinary Studies and subsequently returned to their owners is recorded. They constituted 42.7 per cent of the 82 chronic cases seen between 1991 and 1994; the other 47 horses were euthanased while in hospital. Of the 35 animals returned to their owners four died and 27 were available for follow up; of these 27, 12 were working competitively and six were being trained for future competitive work. It takes at least a year before it is clear whether a horse can compete successfully again but all the surviving animals were capable of being ridden. Some of the horses suffered excessive sweating, had difficulty in swallowing some foodstuffs, or had coat changes for long periods after returning to a normal weight.