126 DISEASES OF THE HORSE. 



Eydrothorax is sometimes difficult to overcome by means of the 

 use of medicines alone, when the operation of tapping the chest is 

 performed to allow an escape for the accumulated fluid. The opera- 

 tion is performed with a combined instrument called the trocar and 

 cannula. The puncture is made in the lower part of the chest, in 

 the space between the eighth and ninth ribs. Wounding of the 

 intercostal artery is avoided by inserting the instrument as near as 

 possible to the anterior edge of the rib. If the operation is of 

 benefit, it is only so when performed before the strength is lowered 

 beyond recovery. The operation merely receives a passing notice 

 here, as it is not presumed that the nonprofessional will attempt 

 it, although in the hands of the expert it is attended with little 

 danger or difficulty. 



We have described here bronchitis, pneumonia, and pleurisy 

 mainly as they occur as independent diseases, but it should be remem- 

 bered that they merge into each other and may occur together at one 

 time. While it is true that much more might have been said in regard 

 to the different stages and tj^pes of the affections, and also in regard 

 to the treatment of each stage and each particular type, the plan 

 adopted of advising plain, conservative treatment is considered the 

 wisest on account of simplifying as much as possible a subject of 

 which the reader is supposed to know very little. 



PLEUROPNEUMONIA. 



This is the state in which an animal is affected with pleurisy and 

 pneumonia combined, which is not infrequently the case. At the 

 beginning of the attack only one of the affections may be present, but 

 the other soon follows. It has already been stated that the pleura is 

 closely adherent to the lung. The pleura on this account is frequently 

 more or less affected by the spreading of the inflammation from the 

 lung tissue. There is a combination of the symptoms of both diseases, 

 but to the ordinary observer the symptoms of pleurisy are the most 

 obvious. The course of treatment to be pursued differs in no manner 

 from that given for the affections when they occur independently. 

 The symptoms will be the guide as to the advisability of giving oil 

 and laudanum for the pain if the pleurisy is very severe. It should 

 not be resorted to unless it is necessary to allay the pain. 



BRONCHO-PLEUROPNEUMONIA. 



This is the term or terms applied when bronchitis, pleurisy, and 

 pneumonia all exist at once. It is impossible for one who is not an 

 expert to diagnose the state with certainty. The apparent symptoms 

 are the same as when the animal is affected with pleuropneumonia. 



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