GRASS FAMILY. 47 



The formation of hydrocyanic acid is due to the action 

 of an enzyme on a glucoside, which resembles that found 

 in almonds. Neither the glucoside nor the enzyme is in 

 itself poisonous. The enzyme is especially active when 

 green sorghum is wilted, and the poison is said to be more 

 plentifully produced in stunted plants, or those of second 

 growth. When the Sorghum has been dried there is no 

 danger, hydrocyanic acid being very volatile, and the 

 enzyme responsible for its formation being in all prob- 

 ability destroyed by the drying. 



The symptoms produced are very striking. Hydro- 

 cyanic or prussic acid is the most rapid poison known. 



Even the dilute form found in these plants 

 Symptoms 



causes symptoms m a few seconds, especially 

 when taken on an empty stomach. The animal becomes 

 giddy or staggers and falls. Heart action is slowed and 

 breathing laboured. Spasms and twitching of the mus- 

 cles are followed by numbness in the limbs, and finally by 

 delirium and death. Bloating is sometimes observed in 

 sheep and cattle, but is not always present. If only a 

 very slight amount of the poison has been eaten the 

 symptoms are less pronounced- Sorghum has, however, 

 been known to become so poisonous that a few mouth- 

 fuls eaten on an empty stomach would kill a cow in ten 

 minutes. An autopsy shows no pathological conditions, 

 but an analysis of the stomach contents of animals lately 

 killed reveals the presence of hydrocyanic acid. The 

 peach-like odour of the poison is usually quite noticeable. 

 Treatment is in most cases useless where any consider- 

 able amount of the poison has been ingested. The animal 

 should be placed with head raised, and, if pos- 



Treatment 



sible, in the shade. If bloating occurs ir 

 cattle the paunch should be punctured, a handbreadth in 



