844 LUNGS AND PLEURiE. 



Some ten years ago two veterinary surgeons of the department of the 

 Aisne, Coulon and Ollivier, practising in a district where perij)neumonia 

 rages, made some extremely interesting observations on pneumonia in 

 the ox. Their object was to distinguish between contagious peri- 

 pneumonia and simj)le pneumonia during life, simple pneumonia having 

 formerly been regarded as a non-contagious peripneumonia. Despite 

 the rather unfavourable conditions in which ordinary practitioners are 

 frequently placed, these gentlemen performed a work of great value. 

 The facts which point to the occurrence of simple pneumonia are as 

 follows : — 



The disease is not contagious. One may allow affected animals to 

 mix with normal subjects without the disease being communicated. 

 Pulmonary exudate from cases of simple pneumonia can be injected 

 into the dewlap and hind quarters of young and adult animals, with- 

 out pathological results. 



The lesions and course of simple pneumonia entirely differ from 

 those of peripneumonia. 



Causation. Simple pneumonia is not common, and only occurs 

 quite exceptionally in fat stock, or in milch cows kept in stables at a 

 regular temperature, as in the north of France and near Paris. 



It occurs most commonly in working animals, which are exj^osed to 

 variations in temperature and to chills. By causing vascular disturb- 

 ance, chill favours microbic infection and visceral inflammation. Trasbot 

 has described the case of an ox w^hich, after having worked hard, and 

 whilst freely sweating, was left exj)Osed to the wind under a shed for 

 about three hours. This animal contracted unilateral pneumonia the 

 following day. 



Coulon and Ollivier have seen the disease in animals living in damp, 

 low-lying valleys, or valleys exposed to the north wind, which are ex- 

 posed in consequence to great variations in temperature. 



The symptoms follow almost the same course as in the horse, and 

 one may distinguish three periods : — 



I. Period of onset. The symptoms which mark the onset of the 

 disease are moderate fever, which progressively increases, and accelera- 

 tion of respiration and of circulation. The number of the respiratory 

 movements rises to twenty or twenty-five per minute, those of the 

 pulse to fifty, sixty, or eighty. The conjunctiva becomes injected, and 

 then of a yellow tint. At this period the appetite never disappears 

 completely, rumination is regular, and there is neither tympanites nor 

 colic. 



These general symptoms, which are not of special significance, are 

 supplemented by more precise local symptoms — an abortive, difficult and 

 painful, cough which is easily induced, and a whitish discharge. The 



