Birds strychnine toxicity

Many birds such as sparrows, blackbirds, rice birds, grackles, and cowbirds can cause heavy loss of grain in rice fields. Because the use of poisoned baits in some countries is often restricted by law or popular opinion, the information presented does not constitute a recommendation on any specific chemical. The use of strychnine-poisoned rough rice (17, 18, 25) against blackbirds, grackles, cowbirds, and English sparrows, wherever the use of poison is permitted, can be effective. Many other toxic chemicals will kill these birds however, domestic poultry and game bird species are relatively much less susceptible to strychnine than to other toxic materials. Therefore, we have in strychnine a fairly effective selectivity which other toxic materials do not offer. 

Strychnine was discovered and identified as the main toxic principle of Strychnos in 1818, although nux vomica, the unpurified plant extract in which it is the active component, had been known and used for both medicinal and criminal purposes for some time. Historic records indicate that the strychnine alkaloid had been used to kill dogs, cats, and birds in Emope as far back as 1640. The structure of strychnine was first determined in 1946 by Sir Robert Robinson and in 1954 this alkaloid was synthesized in a laboratory by Robert W. Woodward. This is one of the most famous syntheses in the history of organic chemistry. Both chemists won the Nobel prize (Robinson in 1947 and Woodward in 1965). 

An example of a stimulant that is also a toxicant is the pesticide strychnine. This alkaloid works by neutralizing glycine, an amino acid responsible for transmitting inhibitory nerve impulses to muscles. Without inhibition, the muscles contract but do not relax. Skeletal muscles become hyperexcited and contract continuously. Limbs become stiff and respiration stops. Animals poisoned with strychnine suffocate and die. This poison is toxic to fish, insects, mammals, and birds. 

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