94 SWINE PRACTICE 



veut over-feeding and most such patients will respond to treat- 

 ment mucli more readily on one-half or two-thirds of the regular 

 ration. 



HYPEREMIA 



Passive hyperemia of the stomach is the result of obstructive cir- 

 culation and usually is evidenced by more or less edema of the gas- 

 tric walls; in extreme cases there may be thrombotic formation and 

 focal or even extensive necrosis. 



Active hyperemia of tlie stomach is much more common than the 

 passive form, and may be either physiologic or pathologic. 



Pathologic gastric arterial hyperemia is caused by irritation, either 

 from chemicals, undue exposure, or infection, and represents the 

 primary stage of inflammation. 



Hyperemia of the stomach is rarely diagnosed as such. It is 

 difficult to draw a line between physiologic and pathologic hyperemia, 

 and unfortunately it is not possible to distinguish between patho- 

 logic active hyperemia and inflammation of the stomach. If such 

 a distinction could be made the inflammatory process could in the 

 majority of c£ises be prevented. 



GASTRIT18 



Gastritis is relatively common in hogs. It results from trau- 

 matic injuries, chemical irritants (poisons), and infection. 



Catarrhal Gastritis 



Catarrhal gastritis is of fairly common occurrence and usually 

 results from mild irritation. It is evidenced by a hyperemia of the 

 mucosa, which appears red, slightly tumefied, and covered with vary- 

 ing quantities of mucus. 



Etiology. — The most common causes of catarrhal gastritis are im- 

 proper feed and irregular feeding. Moldy, musty, sprouted, 

 burned and immature grains are frequently fed to swine, and are 

 not only responsible for many cases of indigestion but also other 

 diseased conditions. The hog is usually considered as the farm 

 scavenger and any food stufi* that is deteriorated is ordinarily con- 

 sidered good enough for swine. Some breeders and feeders cook 

 the food stuff for swine and occasionally such feeds are given suf- 

 ficiently hot to cause irritation not only of the buccal mucosa but 



