420 The Diseases of Animals 



the contraction of the muscles, as chloral hydrate, in 

 dram doses for a medium -sized dog to one ounce for a 

 horse, dissolved in plenty of water. When the spasms 

 occur, a few whiffs of chloroform or ether will lessen 

 their severity. 



Most cases of poisoning by plants occur in the 

 spring, when animals are first turned out to pasture 

 and before the grass is well started. Animals will then 

 eat plants that under other circumstances they would 

 not touch. 



Animals confined in yards or corrals, especially where 

 weeds are starting in the spring, are very likely to eat 

 injurious kinds. They may die from the effects of such 

 poisoning. It is probable that poisonous substances 

 sometimes develop in plants at particular stages of 

 their growth, and disappear as the plants mature. It 

 is probable, also, that animals dying from apparent 

 poisoning may really be destroyed by a sudden change 

 of food, especially from dry food to green ; this is true 

 when the green food is not of good quality, and when it 

 contains weeds and other irritating material. If an ani- 

 mal is hungry and the stomach contains comparatively 

 little food, eating a large quantity of green weeds or 

 similar material brings on acute indigestion, during 

 which decomposition of the contents of the stomach 

 seems to take place, and poisons are formed that kill 

 the animal very quickly by stopping the action of the 

 heart. In such cases, the animals usually show signs 

 of muscular weakness, a dripping of saliva from the 

 mouth, and great debility. They often lie down and die 

 with scarcely a struggle. Whenever animals are to be 



