258 CLINICAL VETERINARY MEDICINE AND SURGERY. 



congestive and haemorrhagic lesions in the nervous centres, particularly 

 in the lumbar portion of the cord and in certain nerves, notably the 

 femorals, are rarely absent. In addition I should mention the con- 

 gestive lesions in certain portions of the intestinal mucous membrane, 

 the swelling and haemorrhages in the spleen, the fatty degeneration of 

 the liver and other glands, and the hyperaimia of most of the viscera 

 and of the bone marrow. 



These appearances are in great part consequent on changes in the 

 blood, and on the uraemia which complicates prolonged cases. 



The pathogeny of haemoglobinuria is variously interpreted. The 

 most recent work published on this question does not appear to have in 

 any appreciable degree advanced it. 



In the nervous or medullary theory, accepted by many writers and 

 remarkably well described by M. Trasbot in the A 7xhives Veterinaircs, 

 the symptoms noted are referred to congestion of the spinal cord or to 

 myelitis. Unquestionably the cord often shows hypenemic and 

 hsemorrhagic changes, but it may well be asked whether these are not 

 due to the same causes as the secondary changes in the viscera ; many 

 persons maintain that they are not constant, and certainly they explain 

 neither hasmoglobinaemia nor hsemoglobinuria. In two post-mortem 

 examinations made during the last few years the cord appeared to me 

 unchanged on naked-eye examination, and the microscope showed no 

 important lesions.* 



xVuthors have at various times traced the disease to congestion of 

 the kidneys or to nephritis. The waste products usually excreted by 

 the kidneys are said to produce general intoxication, changes in the 

 blood-corpuscles, inflammation of muscle, and the train of symptoms 

 which successively appear. M. Lucet, who regards haemoglobinuria as 

 a disease of renal origin, refers the benign cases to an ephemeral but 

 ■excessively acute nephritis. But renal changes appear to be always 

 secondary, consecutive to changes in the blood. Lesions in the epithelial 

 cells lining the renal tubules, like enlargement and pigmentation, are said 

 to be caused by the elimination through the kidney of products resulting 

 from destruction of red blood-corpuscles, or the transformation of 

 haemoglobin. Experiments carried out in company with M. Roger 

 have satisfied me that urinary intoxication produced by injecting fresh 

 filtered urine into the horse's jugular produces none of the symptoms 



* 111 his treatise on nervous affections in the horse, just published, Dexler regards 

 haemogiobinuria as a disease of the cord. He states that the dominant symptoms are those 

 of a medulla-ry affection, and he claims to have foimd in the anterior horns of the lumbar 

 portion of the cord lesions which explain these symptoms. 



