NONCONTAGIOUS DISEASES OF THE ORGANS 

 OF RESPIRATION. 



By William Heebekt Lowe, D. V. S. 

 DIAGNOSIS. 



In the determination of disease in the human being the physician, 

 in making his diagnosis, is aided by both subjective and objective 

 symptoms, but the veterinary physician, m a very large majority of 

 eases, is obliged to rely almost solely upon objective symptoms, and 

 perhaps in no class of diseases is this more true than in the explora- 

 tion of those under consideration. This condition of affairs has a 

 strong tendency to develop observation and discernment in the veter- 

 inarian, and not infrequently do we find that the successful veteri- 

 nary practitioner is a very accm-ate diagnostician. In order to 

 make a differential diagnosis, however, it is not only necessary to 

 know the structure and functions of the organs in health, but to 

 adopt a rigid system of details of examination, without which suc- 

 cessful results can not be reached. 



History. — The history of a case should always be ascertained so far 

 as possible. The information obtamed is sometimes unsatisfactory 

 and not to be depended upon, but even when this is the case it is 

 advisable to weigh the evidence from every point of view. 



In coimection with the history of every case it is always of pri- 

 mary importance to ascertain the cause of illness. A knowledge of 

 the origin and development of a disease is important, both in making 

 a diagnosis and in formulating the treatment. Exposure to cold and 

 dampness is frequently the exciting cause of affections of the organs 

 of respiration. 



The experienced practitioner is always sure to ascertain whether 

 the particular animal he is called on to attend is the only one in the 

 stable or on the premises that is similarly affected. If several ani- 

 mals are similarly affected, the disease may have a common cause, 

 which may or may not be of an infectious nature.. 



Another thing that the experienced practitioner ascertains is what 

 previous treatment, if any, the animal has had. Medicine given in 

 excessive doses sometimes produces symptoms resembling those of 

 disease. 



The hygienic and sanitary conditions must always be considered 

 in connection with the cause as well as the treatment of disease. 



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