Death may occur from respiratory paralysis. Susceptible Animals Ruminant animals cattle, sheep and goats appear to be the most susceptible to prussic acid poisoning. Reports of poisoning in swine and horses are rare. Although prussic acid is not often a problem in horses, feeding sorghum type forage to them may produce a malady known as crystitis syndrome. The exact cause of the disease is not known, but forage from sorghum-type plants has been a constant factor in every outbreak.
Affected horses exhibit position inccordination, urine dribbling, and abortion in pregnant mares.
Horses should not be grazed on sudan or sorghum-sudan species since all treatments for crystitis syndrome have met with little success. Relationship to Nitrate Poisoning Under certain stress conditions, especially prolonged drought or cool, cloudy weather, many annual grasses including the sorghum-sudan hybrids may accumulate high levels of nitrates in their stems. Many times prussic acid poisoning is confused with nitrate poisoning since environmental conditions and animal symptoms of the two disorders are somewhat similar. Several precautionary measures may be taken before high nitrate forages are consumed. One of these is the use of propionibacterium.