CHAPTER XVI 



DISEASES CONNECTED WITH FEED 



SPOILED AND DISEASED FEEDS 



Many digestive derangements are caused through dietetic 

 errors caused by spoiled feeds. It is a common and popular 

 thought that spoiled feed, not fit for human consumption, is 

 good enough for the chickens. Food that is injurious to the 

 digestive canal of one group of animals is pretty likely to prove 

 just as injurious to another. There are very few exceptions 

 to this rule. The fact that a buzzard can eat carrion and thus 

 spread disease does not imply that all kinds of birds can eat 

 spoiled feed with impunity. The anatomic and microscopic 

 structure of the digestive tract of all animals is pretty much 

 alike, as we znay see under the section on Digestion. All 

 animals make use of the same nutrients, assimilate them, and 

 build organic structures out of them. So far as we know, fat 

 in the body of a hen is built up by the same process as fat in 

 the body of a cow or a human. Its sources may be the same. 

 AP eat similar food — that is, the same kind of carbohydrates, 

 hydrocarbons, protein, and ash. All are affected in a similar 

 manner when poisonous substances are taken into the body. 

 Some withstand certain poisons better than others. It was 

 formerly thought that it was impossible to poison birds with 

 strychnin, and one author went so far as to say that pigeons ate 

 strychnin with impunity, but that birds can easily be poisoned 

 by strychnin is shown by the experiments of the author, in 

 which experiments the medicinal dosage of sulphate of strych- 

 nin was found to be from K to 34 grain to an adult hen. 

 One grain in solution, given on an empty stomach, always 

 proves fatal in a very few minutes. Therefore, birds have a 

 greater resistance to strychnin per body weight than other 

 animals, making the medicinal dose greater, and hence the 

 lethal or poisonous dose correspondingly larger. 



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