114 



VETEEINAEY TOXICOLOGY 



occasionally found wild in England. Poisoning of animals 

 by eating the opium poppy is, however, unknown. 



The juice contains some fifteen alkaloids most of which 

 are present in very small proportions. The table displays 

 the chief of these with the average percentages in which 

 they are found in opium. 



The other alkaloids are not important. 



Poisoning by morphine is rare amongst animals, this 

 alkaloid affording a good illustration of the variation in the 

 action of a cerebral poison according to the degree of 

 nervous development. Doses ordinarily given to dogs for 

 anaesthetic purposes would prove fatal to a man. Horses 

 and ruminants are less susceptible, and since in the horse 

 the brain is relatively less highly developed than the cord, 

 the spinal are more marked than the cerebral effects. 



Toxie Doses. — Kaufmann gives the toxic doses on 

 subcutaneous injection as : 



Horse 

 Ox ... 

 Small dog. 

 Large dog 



45 to 75 grains 

 75 to 120 „ 



1-5 

 15 



These doses are probably too low ; for the horse 75 to 100 

 grains and for the dog about 4 grains per pound body 

 weight are, however, fatal. Wooldridge uses i to ^ grain 

 for anaesthesia in small, and 2 grains in large, dogs. It is 

 very doubtful if poisoning by the mouth ever occurs, and it 

 has been proved to be impossible to kill a pigeon in this 

 way. Doses have been given experimentally to the pony 

 reaching 60 grains by the mouth, without evoking marked 

 symptoms, and after slaughter there was no sign of action 

 beyond impaction of the stomach contents due to gastric 

 paralysis. 



