GENERAL THERAPEUTICS OF FEVER 81 



vention of bacteria from the resorption of products resulting from 

 the disintegration of the blood (aseptic fever). 



1. In wound fever, the formation of antitoxic substances is 

 accompanied by increased metabolism, disturbance of heat regu- 

 lation and stimulation of the heat centre, the result of the resorp- 

 tion of dissolved bacterial toxins and certain chemical substances 

 from the wound secretion. Wound fever is therefore to be re- 

 garded as a resorption fever. When the materials absorbed are 

 bacteria or toxins produced by the bacteria in the wound the 

 term septic or bacteiial fever is used (infectious fever, intoxication 

 fever, septicaemia, pyaemia). In a large number of cases, fever is 

 associated with entirely benign woimds Hke those following castra- 

 tion, and non-infected wounds such as subcutaneous bone frac- 

 tures and blood extravasations. Fever in these cases probably 

 occurs from the resorption of the ferment-like decomposition 

 products of the blood and tissues, the action of which upon the 

 blood and the nervous system is similar to that of the bacterial 

 toxins. A fever of this character is called aseptic or ferment fever. 

 These active chemical substances are blood and tissue ferments 

 (fibrin ferment, histozyme), organic toxins arising from the decom- 

 position of the tissue cells (nuclein from the nuclei of the white blood- 

 cells, free haemoglobin) and sometimes also glandular secretions. 



2. The infectious fever of the acute infectious diseases (con- 

 tagious pneumonia, strangles, canine distemper, foot-and-mouth 

 disease, etc.) is produced in the same manner as wound fever, 

 the infection and intoxication of the blood occurring usually 

 through the respiratory or gastro-intestinal mucous membrane. 



3. As non-bacterial fevers there are yet to be mentioned ner- 

 vous fever (very painful conditions), rheumatic fever (diseases due 

 to chilling), inanition fever (anaemia), also the fever of heat stroke, 

 fatigue (restraint of horses), and overheating (long rides, casting). 



Physiology of Heat. — ^Animal heat arises from the activity of the 

 body cells, especially the muscle and gland cells, chiefly from 

 the burning up (oxidation) of the carbohydrates. The constancy 

 of the normal temperature is maintained by the regulating activity 

 of the heat centre in connection with the vasomotor nervous sys- 

 6 



