GENERAL DISEASES. 83 



former kind of abscess the infarction is due to the lodg- 

 ment of an infective clot in a terminal artery. The most 

 frequent seats of these embolic abscesses, as they are termed, 

 are the lungs especially, the liver, spleen, kidney, and brain, 

 but they may occur in any vascular part of the system. 



They vary in size, and are usually multiple, and may be 

 very numerous. 



The other kind of abscesses are diffuse suppurative 

 inflammations in the subcutaneous and connective tissues, 

 in the joints, and in the serous membranes. They are fairly 

 often met with, and may or may not coexist with the em- 

 bolic abscesses above mentioned. 



Besides the secondary abscesses, there are other lesions 

 found on post-mortem examination. The wound, if pre- 

 sent, is in a sloughing condition, perhaps surrounded by 

 diffuse infiltration of the tissues, and is offensive. There 

 are extensive thrombi in the veins leading from the point 

 of infection ; these thrombi are undergoing infective puri- 

 form softening. 



The blood is darker than in the natural condition, and 

 not disposed to coagulate, and contains excess of ivhite blood- 

 cells. Congestion of the lungs is generally present; the 

 spleen is large and pulpy; the liver and kidneys show 

 granular degeneration. 



Etiology of Pyaemia in the Horse. — Pysemia is chiefly 

 developed in connection with injuries and wounds, and more 

 especially in connection with suppurative-action in bone. 



It may accompany various diseases, notably the specific 

 fevers. 



Symptoms of Pyaemia in the Horse. — Rigors and 

 localized perspirations. Sudden elevation of temperature, 

 which rises and falls irregularly. It may rise to 106° or 

 more, and, though variable, is always high. 



Pneumonic symptoms are often developed from the 



6—2 



