Etiology. 531 



socalled * ' Schweinsberg Disease" was seen only in horses that 

 liad grazed on lands which are often flooded, or that had received 

 food grown on snch land, while the farms on higher gronnd 

 in the same district never had cases of the disease or suffered 

 only to a slight extent. The plants grown in these districts 

 contain some substance that is irritating to the liver tissue. 

 Schlegel and Adelmann have recently shown that the disease 

 may be no more than a generalized sclerostomiasis, and that the 

 chronic inflammatory changes in the liver are produced by the 

 migrations of the larv« of sclerostomes. 



The idea that certain plants contain substances capable of 

 causing chronic hepatitis does not agree with the experience ob- 

 tained with regard to chronic lupinosis. However, the disease has 

 been observed after long continued feeding with several plants 

 of the Senecio group (S. Jacobea, S. latifolia, S. Burchelli) 

 in New Zealand, North America and South America (Smith, 

 Gilruth, Robertson, Wyath-Johnston, Schroder), and it has been 

 set up experimentally in cattle and horses by Gilruth and Rob- 

 ertson. Guittard has observed chronic hepatitis in geese fat- 

 tened on maize. 



Gilruth fed two six-nionths-old calves on six pounds of S. Jacobea daily. 

 Both calves died at the end of four weeks. To the naked eye their livers appeared 

 unaltered but under the microscope there could be detected a perivascular connective 

 tissue, slight thickening of the capsule and coniuiencing destruction of the liver 

 cells. 



Eobertson experimented with calves, adult bovines and horses, and found that 

 the administration of large quantities of S. Burchelli and latifolia caused gastro- 

 enteritis and venous hyperemia of the liver in a few days, while small quantities 

 fed over a period of weeks caused atrophic cirrhosis of the liver. 



Since chronic hepatitis is frequently met with in people 

 addicted to alcohol, the idea suggests itself that alcohol may be 

 the cause of the disease in animals, in as much as it is present 

 in the swill tub. One must not lose sight of the effect of fer- 

 mentation products that may be formed in this food during stor- 

 age ; and especially, as it has been shown by v. Baumgarten and 

 Hansemann to be impossible to produce chronic hepatitis in 

 experimental animals by the systematic introduction of alcohol 

 into their bodies, either by subcutaneous injection or by inges- 

 tion. 



In certain cases the disease is set up by chemical substances 

 contained in rotten or mouldy food, or by certain digestive dis- 

 orders of the alimentary canal itself. Of 350 pigs killed, be- 

 longing to innkeepers and brewers, Tschauner found 13 af- 

 fected, but out of 5,700 farm pigs killed at the same time, only 

 3 were found similarly diseased. The former had been fed on 

 the waste (potato peelings, etc.). Possibly the small percentage 

 of alcohol present among the fermentation products played some 

 part in the production of the disease. In a case described by 

 Begeng the disease was causally connected with a chronic gas- 

 tro-enteritis. Begeng agrees with Siegenbeck van Henkelom 

 that hypertrophic cirrhosis of the liver is produced by toxic 



