DISEASES OF THE RESPIRATORY ORGANS. 35 



(BRONCHITIS. 



An inflammation seated in the lining membrane of the larger bronchial 

 tubes constitutes the disease called bronchitis, a very common affection 

 among dogs. It is generally ushered in by an inflammation of the mucous 

 membrane of the nasal passages, which commencing in the nostrils travels 

 downward, to the lungs. 



The disease may be divided into two stages, which can be conveniently 

 termed the dry and the moist. From the occurrence of the first symptoms 

 in the nose, in from one to three days the disease makes the transit to the 

 larger bronchial tubes, the mucous membrane of which becomes dry, red- 

 dened, swollen, and sensitive. In the progress of the affection, after two 

 or three days, the mucous secretion , which has been absent or scanty, 

 reappears and is abnormally increased. 



Bronchitis may be primary or secondary, that is it may occur as a distinct 

 affection or be developed as a complication of certain diseases, such as 

 pneumonia, or consumption. 



It maybe either acute, sub-acute, or chronic, as based on the differences 

 as regards the severity and duration of the inflammation. 



Causation. — Exposure to damp and cold; violent exercise, and subse- 

 quent confinement in draughty kennels; changes in the weather, and 

 some special atmospheric influence not understood. This is to be inferred 

 when the disease prevails as an epidemic. 



Symptoms. — Shivering, and the common evidences of catarrh, are the 

 primary symptoms noted, followed by some fever, higher pulse, thirst, 

 loss of appetite, dulness and general lassitude. The cough is at first dry 

 and painful, but not suppressed. This changes as the mucous secretion 

 becomes abundant, then the pain abates, the cough loosens and has a softer 

 tone. Respiration is usually unaffected, rapid breathing being observed 

 only in exceptional cases, in which the mucous secretions accumulate, and 

 obstruct the bronchial tubes. The expectoration is at first small and scanty, 

 later copious and frothy. The eyes are reddened, the nose hot, and glued 

 with a thick mucus which becoming free and thin, is accompanied with 

 frequent sneezing. 



These symptoms are present in ordinary bronchitis. An unfrequent and 

 graver form is developed when the inflammation affects the smaller tubes. 

 This is termed capillary bronchitis, and differs widely from the ordinary 

 acute disease. It is an exceedingly grave affection, and the danger proceeds 

 from obstruction to the current of air to and from the air-cells. This 

 obstruction is due to the small size of the affected tubes. The 'swelling of 

 the mucous membrane, and the presence of the muco-purulent liquid, 

 which in the larger tubes do not interrupt the free passage of air during 



