Diarr/ura, Scourhig. 305 



As examples of the secretion of irritant matters from the blood 

 may be mentioned almost all the different agents used as purga- 

 tives, and purgative agents accidentally taken in, these being as 

 a rule absorbed and later secreted again on the intestinal surface, 

 increasing the secretions in their passage : — also the morbid pro- 

 ducts of fevers which irritate the intestinal mucosa and glands 

 as the}' are thrown out by them (rinderpest, lung plague, 

 Southern cattle fever) : — the purgative waters on certain 

 "scouring lands" act in a similar way. Under the head of 

 reflex action may be named the chills from exposure to cold 

 rains, night dews, damp stalls or beds, and damp, hot buildings, 

 seasons and localities. Under the head of nervous causes must 

 be included strong emotions as excitement, fear, etc., which lead 

 to increase of both secretion and peristalsis. Some horses are 

 very subject to this and are known as " washy ". These have 

 usuall}' a slim abdomen and long loin, and scour whenever they 

 are put to hard work. Other nervous animals with good con- 

 formation, but which fret under saddle or in harness will scour 

 under specially severe work or under excitement. This is espe- 

 cially common in young colts while being "broken", and will 

 occasionally show in mares which are in heat. Cattle that have 

 been on a speciall}' succulent diet (turnips, beets, ensilage, grass) 

 are liable to scour profusely if driven far or fast, and stock men 

 seek to obviate this by feeding some dry bran, meal, and above 

 all fresh dry brewer's grains just before starting. Cows running 

 at large when in heat are very liable to scour. An exclu.sive diet 

 of turnips or beets will keep cattle in a chronic condition of mild 

 diarrhoea, though not enough to interfere with rapid improve- 

 ment in flesh. Chronic disea.ses of the liver by obstructing the 

 flow of blood through the portal vein, cause intestinal congestion 

 and predispose to diarrhoea. 



Of the various domestic animals horses are the most liable to 

 superpurgation, from an undue dose of aloes acting on the very 

 large colon and caecum. Hence the importance of using such an 

 agent carefully in the young, fat or debilitated especially, of the 

 avoidance of cold drinks or exercise to excess after the aloes has 

 been given, and of keeping from work during its operation or 

 immediately after. 



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