478 DISEASES OF THE BRONCHI. 



becomes, as the exudation into the bronchi increases, less hard, 

 and Avith it there is sometimes a discharge into the month 

 or through the nasal openings of a ropy, tenacious mucus, 

 tending to give the mouth a moist and ghiey feeUng. All 

 these symptoms, which are the true pathognomonic indications 

 of the disease, are apt to vary according as the morbid action 

 varies from a very moderate congestion or inflammation of the 

 large bronchi, to severe involvement of the minute and ultimate 

 ramifications, or to collapse of pulmonary tissue and oblitera- 

 tion of air-tubes. 



b. Secondary Bronchitis, BroncJtitis accompanying certain 

 general Diseases and Conditions of Blood, Contamination. — 

 This form of bronchial inflammation is sometimes met with 

 in the horse in rheumatism and glanders-farcy, while in 

 young animals suffering from specific arthritis it is a common 

 complication, and is here found in conjunction with pulmonary 

 embolism. When found in these relationships its symptoms vary 

 little save as respects severity from bronchial inflammation oc- 

 curring independently and apart from other diseased conditions. 

 lu such cases the bronchial symptoms do not precede the 

 manifestation of the general or specific disease, but are usually 

 developed during its progress, and seem to depend for their 

 existence on the morbid state with which they are associated. 



c. Mechanical Bronchitis. — This form of acute bronchitis in 

 the horse is not, as in other of our patients, of a parasitic origin, 

 but is generally the result of the contact of some irritant with 

 the membrane of the air-tubes. It occurs by the accidental 

 passage into the trachea of medicinal agents given in the form 

 of draughts, also from the entrance into the tubes of heated 

 sm®ke, air, or other volatile agents, in the case of exposure to 

 these, as in buildings which have been destroyed by fire. The 

 symptoms exhibited in this form are eminently characteristic 

 of acute bronchial inflammation. They may be of all degrees 

 of severity, from the most moderate irritation, causing mere!}- 

 cough, Avith the ejectment of a little frothy mucus, and con- 

 tinuing only for a few days, to the destruction of the lining- 

 membrane of the tubes as a whole, inducing much distress, Avith 

 excessive expectoration and discharge from the nostrils of 

 frothy, blood-stained mucus, terminating in asphyxia and 

 death. The symptoms of distress and irritation folloAV imme- 



