Depraved Appetite. Stump Sucking. Pica. 77 



animal is doubtless at times encouraged by the taste of the salts of 

 perspiration, but in other cases it has all the appearance of a 

 mutual kind service as tlie cow with itching head will walk up 

 and present it to its fellow which rarel}^ fails to respond to the 

 invitation. Stump licking is not unconnnon. 



Sheep shut up in the winter get in the habit of chewing each 

 other's wool, thus virtually depilating their fellows and accumu- 

 lating wool balls in their stomachs. 



Pigs when running at large eat human faeces often infecting 

 themselves with the cysticercus cellulosa, and devour their own 

 or their fellows' bristles, which form ovoid and irritating aggre- 

 gations in the stomach. 



Puppies are proverbial for swallowing every small object that 

 comes in their way, coal, pebbles, marbles, leather, hair, etc., 

 with the result of inducing nausea and vomiting, or more seriou.sly, 

 wounds of the stomach, gastritis and enteritis. In older dogs 

 the habit is more likely to imply rabies. 



Solipeds will lick and swallow each others hair, eat off the 

 hair from each other's tails and manes, eat their clothing, lick 

 the wall plaster, earth or sand, and even the manger or rack. 

 The last named habits are usually coiuiected with disease. 



Fowls can digest almo.st anything they swallow, but if they 

 take to picking their feathers, they create serious injury to the 

 skin and indirectly to the general health. 



Causes and Nature. In general terms it may be .said that the 

 causes of depraved appetite are very numerous, so that the 

 trouble must be looked upon as a symptom of many morbid con- 

 ditions in place of a disease sui generis. 



Heredity has been invoked as a cau.se, mainly, it would appear, 

 because the disease appears enzootically on certain exhausted 

 soils, or in herds kept in the .same unhygienic conditions. In 

 such cases the real cause is usually to be found in faulty condi- 

 tions of .soil, water, buildings, food, etc., on the correction of 

 which the trouble disappears. When, however, from a long con- 

 tinuance of unhygienic conditions, a weakness of constitution is 

 tran.smitted from parent to offspring, such hereditary debility 

 maj' be accepted as a predisposing factor. 



An exhausted soil, lacking especially the elements of lime and 

 phosphorus, is a common cause, though by no means the only 



