BRONCHO-PNEUMONIA IN SOI.IPEDS. 



Synonyms : Catarrhal pneumonia, lobular pneumonia, capillary- 

 bronchitis, bronchiolitis. 



Definition. A circumscribed inflammation of the lungs, 

 usually limited to one or a few connecting lobulettes at one place, 

 often multiple, and usually the result of extension from the 

 bronchioles. 



Causes. This is virtually the same malady described under 

 the name of capillary bronchitis which can hardly fail to become 

 extended to the alveoli and lung. If capillary bronchitis does 

 not speedily subside, therefore, it inevitably merges into broncho- 

 pneumonia. Again as bronchitis is usually attended and main- 

 tained by abundant microbian invasion, and it may be by various* 

 species of organisms, so broncho-pneumonia is a microbian disease 

 without any constant and definitely fixed, single microorganism 

 as its essential cause. All the irritant causes which lay the 

 system open to bronchitis become equally important factors in 

 broncho-pneumonia, and all climate vicissitudes and other influ- 

 ences which operate to produce the first disease also tend to pro- 

 duce the other. Finally it may occur from inhalation of irritant 

 food or other elements and their lodgement in given bronchial 

 tubes ; or it may be the result of the localization of given infec- 

 tions (tuberculosis, contagious pneumonia) in which case the 

 disease takes its name from the infection in question. 



Prolonged decubitus on the side as in acute laminitis, quittor, 

 pricks with suppuration of the subcorneal tissues, penetrating 

 wounds of the perforans, navicular pulley or coffin joint, acute 

 rheumatism or arthritis and other affections that incapacitate the 

 animal for standing, tends to produce hypostatic congestion of 

 the lower lung, and this at once weakens the part and renders 

 the stagnant liquids in the bronchioles and parenchyma an invit- 

 ing culture medium for invading microbes. These microbes may 

 enter by the trachea and bronchi, or they may be carried in the 

 blood from the lesion in the affected limb and reaching the debili- 

 tated and susceptible bronchioles and their contained serum, they 

 at once colonize there and in the mucosa, and bronchitis is estab- 

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