356 PRINCIPLES OF VETERINARY SURGERY 



of purulent globules, and the other liquid, which is simply 

 serum. Serum and leucocytes are not in unchangeable pro- 

 portions : The first is in proportions of 7 to 10, 8 to 10, or 9 

 to 10; and the second of 4 to 10, 3 to 10, or 2 to 10. 



The solid part of pus contains leucocytes belonging to dif- 

 ferent varieties. There are also modified fixed cells, connec- 

 tive tissue fibers, elastic fibers, hematic fibers or fibrin, and 

 crystals of various kinds. Different parasites, — echinococci, 

 botryomyces, — may also be found. These different elements 

 sooner or later, undergo fatty degeneration. In other cases 

 the serum being absorbed the pus is transformed into a 

 cheesy mass which becomes harder and harder until it resem- 

 bles chalk, and which is infiltrated with calcareous deposits. 

 The serum separated by filtration is a clear liquid of a 

 yellowish hue, which becomes coagulated from the effects of 

 heat and of nitric acid. It contains lecithin, cholesterin, 

 fatty bodies, chloride of sodium, carbonates and phosphates, 

 to which it owes its alkalinity. 



DIAGNOSIS. — The diagnosis of superficial abscesses is 

 always easy, but deep collections of pus may present serious 

 difficulties. Blood tumors, cysts and hernias are the ailments 

 which may be confounded with abscesses. Blood tumors are 

 rapidly formed, are immediately fluctuating, and they become 

 crepitant when coagulation has taken place. A cyst is uni- 

 formly fluctuating, without oedema and without any sign of 

 inflammation. Hernias, especially in the bovine species, may 

 ie confounded with abscess, which they often accompany, 

 and, like them, may on their first appearance be accom- 

 panied with oedema. When the latter disappears the proof of 

 the hernial orifice removes every doubt. When the abscess 

 is deep there must be no hesitation about resorting to ex- 

 ploratory puncture, which is always free from danger. This 

 recourse removes every doubt and may furnish a basis for 

 therapeutic purposes. 



