GENERAL THERAPEUTICS OF THE DISEASES OF THE 

 RESPIRATORY APPARATUS 



Pathology. — Of the numerous diseases of the respiratory organs, 

 those which are the object of veterinary treatment include nasal, 

 larjTigeal and bronchial catarrh; the more severe forms of rhini- 

 tis, laryngitis, tracheitis and bronchitis; oedema of the glottis, 

 oedema of the lungs, roaring, active and passive hyperemia of the 

 lungs, the different forms of inflammation of the lungs, emphysema 

 of the lungs and pleuritis. More rarely parasitic diseases (lung 

 worm epidemics, pentastomes, oestrus larvae) and tumors (nasal 

 cavity, larynx) are presented for treatment. On the other hand, 

 secondary inflammatory processes occur very frequently in the 

 respiratory mucous membrane in the course of infectious diseases 

 (strangles, contagious pneumonia, influenza, canine distemper, 

 malignant catarrhal fever, etc.). 



Physiology. — The natural protectives of the respiratory organs 

 are the layer of mucus which covers the mucous membrane and 

 the ciliated epithelial cells of the membrane, the cilia of which 

 carry out by their movement any foreign bodies which may enter. 

 At the same time, the air passages with their extensive surface and 

 recesses serve to warm the air and filter out the dust. Finally, 

 for the forcible removal of foreign bodies and disease products 

 there are certain defensive reflexes (sneezing, coughing). 



The pulmonary respiration, to which the cutaneous respiration 

 can be to a certain degree compensatory, consists of an interchange 

 of gases between the blood and the external air (carbon dioxide, 

 oxygen). This gaseous interchange is facilitated by the continual 

 change of air (inspiratory diaphragmatic contraction, expiratory 

 lung elasticity), the extensive surface of the lungs (in the horse 100 

 times the body surface) and the very thin diffusion membrane 

 (alveolar walls). In diseases of the lungs, these principal factors 

 of respiration are more or less interfered with (pneumonia, em- 

 physema). 



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