HcEmoglobincEm.ia . — Azotc^mia. — Etc. 449 



oedema and swelling, but not unfrequentl}' there are blood ex- 

 travasations varying in size from a pin's head upward and giving 

 a dark red aspect to the affected tissues. Under the microscope 

 the affected fibres are seen to have lost their transverse striation 

 and to have assumed a more or less granular or hyaline appear- 

 ance. Next to the gluteal muscles, these changes are frequently 

 found, in the muscles of the thigh (especially the rectus femoris, 

 and triceps extensor cruris), and in those of the loins (psoas, 

 ilio-spinalis, and longissimus dorsi). Exceptionally the pectoral 

 muscles are involved or even the abdominal muscles. A con- 

 siderable straw-colored oedema may be found in the inter- 

 muscular connective tissue. 



The red bone marrow primarily of the large bones of the limbs 

 (femur, tibia, humerus, radius,) and less frequently of other 

 bones, even of the vertebrae, is often the seat of intense vascular 

 congestion and even of hemorrhage. The medullary matter is of a 

 deep red or black color, and there is an abnormal accumulation of 

 red globules in various conditions of growth and destruction (red 

 nucleated corpu.scles, fragments of corpuscles, colored granules). 

 Dieckerhoff considers the condition one of osteomyelitis, but it 

 seems to be rather a sudden, extraordinary exaggeration of the 

 processes of blood metamorphosis. Neumann found that when 

 the blood regeneration process is very active even the yellow 

 marrow may be changed into red, and this throughout all the 

 bones of the extremities. 



The kidneys are usuall}' the seat of congestion, and black spots 

 of infarction, when the disease has lasted for twenty-four hours. 

 In rapidl}' fatal cases they may appear normal. There may be 

 enlargement of the kidneys with softening and granular degen- 

 eration of the renal epithelium in cases that survive for some 

 days, 



The bladder <zo\\K.2i\\\s dark brown or red glairy urine of a high 

 density and loaded with urea, haemoglobin, etc. 



The terminal portio7i of the spinal cord and the lumbo-sacral 

 plexus, or some of its branches, are sometimes blood stained, or 

 the seat of an exudate or surrounded by one. 



Symptoms. In the regular type of haemoglobinaemia in the 

 horse the history of the attack is highly significant. The subject 

 is in good working condition, he may be fat, or lean, but in either 

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