Rather than expose the entire herd to danger, use test animals for brief periods when the silo is freshly opened or when turning onto questionable pasture. If large quantities of forage high in prussic acid are consumed rapidly. However, the usual situation is that the animals consume smaller quantities of the forage over a longer period, causing first salivation, then a gradual increase in respiratory rate, followed by staggering, falling, severe convulsions and finally death within 45 minutes. Generally, animals that survive 2 hours after the onset of symptoms will recover. Obviously, immediate treatment by a veterinarian is necessary to save the animals.
Treatment includes administering sodium nitrite and sodium thiosulfate.
Poisoning caused by prussic acid is somewhat similar to nitrate poisoning. Simultaneous treatment with sodium thiosulfate converts the newly formed cyanmethemoglobin to thiocyanate and hemoglobin, which permits the blood to again transport oxygen normally. Issued in furtherance of the acts of May 8 and June 30, 1914.