CONGESTION OF THE LIVER. 



Ph5-siological]3' 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, iusufficiency of tricuspid valve, pulmonary emphysema or congestion. 

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

 circulation, dilatabilit}' of hepatic vascular system, compression of lung by 

 false membranes, cedema, 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 en- 

 largement to 20 or 30 pounds, and dark red color, darker spots of extrava- 

 sation, hepatic vein congestion in centre, and portal vein congestion in 

 periphery of acinus, softening, granular, fatty, nuclei disappear from 

 hepatic cells, nutmeg liver, cirrhosis. vSymptoms : general febrile symptoms, 

 great prostration, drowsiness, slight colics, arched loins, trembling or jerk- 

 ing, 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: goodhygeine, 

 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. 



Phy.siologically the liver undergoe.s hypersemia in connection 

 with an abundant meal and active digestion. Within the limits 

 of health it may increase one-thhd in bttlk and weight. When 

 this hyperaemia attends on temporary idleness and rich feeding it 

 may overstep the limits of health and become pathological. Other 

 cau.ses 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 swamp3' 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- 

 48.^ 



