CONGESTION OF THE LIVER. 



Physiologically after a meal is hyperaemic, and may increase one-third. 

 Rich feed and temporary idleness may cause morbid congestion. Other 

 causes are : ptomaines and toxins in spoiled food, hepatic irritants, damp, 

 hot, tropical climates, warm, damp, buildings, overfeeding, dilated right 

 heart, insufficiency of tricuspid valve, pulmonary emphysema or congestion. 

 Absence of valve between the right heart and hepatic veins, slow hepatic 

 circulation, dilatability of hepatic vascular system, compression of lung by 

 false membranes, oedema, hepatization, infarction, hydrothorax. In horse : 

 special causes : spoiled fodders, carminatives, volatile oils, work in hot sun, 

 vaso-dilatation in heat and atony, falls, kicks, goring, blows ; passive forms 

 from obstacles to the circulation. Lesions : Hepatic enlargement to 20 or 

 30 pounds, and dark red color, darker spots of extravasation, hepatic vein 

 congestion in centre, and portal vein congestion in periphery of acinus, soft- 

 ening, granular, fatty, nuclei disappear from hepatic cells, nutmeg liver, 

 cirrhosis. Symptoms : general febrile symptoms, great prostration, drowsi- 

 ness, slight colics, arched loins, trembling or jerking, lies on right side, 

 percussion on last ribs painful, slight icterus and increased urination and 

 urea. In passive cases, less icterus and kidney trouble ; tends to intestinal 

 catarrh and ascites. Prevention : good hygiene, moderate laxative ration, 

 cool air, exercise. Treatment : green or laxative foods, salines, derivatives, 

 water at will, always before morning feed. In dog : overfeeding, indolence : 

 pulmonary and circulatory troubles. Lesions : nutmeg liver, degeneration, 

 cirrhosis. Symptoms : pampered idleness, obesity, pulmonary or cardiac 

 disease, intestinal catarrh, piles, ascites, slight icterus, percussion tenderness 

 of right hypochondrium, lying on right side, increase of percussion flatness. 

 Treatment : saline purgatives or laxatives, antiseptics, restricted laxative 

 diet, open air exercise, derivatives, etc. 



Physiologically the liver undergoes hypersemia in connection 

 with an abundant meal and active digestion. Within the limits 

 of health it may increase one-third in bulk and weight. When 

 this hypersemia attends on temporary idleness and rich feeding it 

 may overstep the limits of health and become pathological. 

 Other causes of pathological congestion are, tainted food rich in 

 ptomaines and toxins, food injured by cryptogams, and food that 

 contains principles irritating to the liver. It is especially common 

 in swampy regions in tropical or semi-tropical latitudes, and where 

 the warm air is surcharged with moisture. Hot, close, damp 

 stables, with over-feeding and lack of exercise in the pampered 

 horse or dog, or under the forcing system of feeding for exhibi- 

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