408 THE PRACTICE OF VETERINARY MEDICINE. 



and formed of salts of lime, magnesia, hair, etc. The name 

 ' dust ball,' was given to these concretions from the fact that 

 they are most frequently found affecting horses that are fed 

 upon the sweepings of flour mills. These concretions are 

 formed in the intestinal canal. Usually there is a piece of 

 brass, iron, stone, oat, or something of that sort, which 

 forms a nucleus around which foreign bodies collect and 

 adhere, until the mass attains a large size and usually causes 

 death. Sometimes calculi of an enormous size have been 

 expelled from the bowels by the aid of enemas, etc., and 

 the animal's recovery effected. Balls composed of hair are 

 oftenest seen in pigs ; are also found in cattle in connection 

 with the reticulum ; and occasionally a horse may have a 

 hair ball. They are formed as a result of the common 

 habit animals have of licking themselves and each other ; 

 a certain portion of hair being drawn away by the tongue 

 and swallowed, until after a time a hair ball is formed of 

 considerable proportions. These balls may exist within the 

 intestinal canal for a very long period and not seriously 

 inconvenience the animal ; but when they attain any very 

 great size they interfere with egestion, and finally, unless 

 expelled, cause death. 



Symptoms. — The animal manifests uneasiness, and appears 

 to be suff'ering from an attack of colicj for which disease 

 he may be treated, and recover only to be attacked again 

 at some future time. A peculiar sighing sort of respiration 

 may be noticed during the continuance of the attack ; the 

 pulse runs down ; obstinate constipation is present ; and 

 inflammation may set in. The patient in this disease also 

 shows the peculiar symptom of sitting upon his haunches 

 — this symptom is to be regarded as a bad sign when 

 occurring after the animal has suffered for any length of 

 time, and it may be regarded as incidental to rupture ; 

 however, it is not to be regarded as an infallible sign of 



