PLEURISY. 647 



walls of the tliorax, a natural result of a diffuse and intense 

 inflammation ; and that in pleuro-pneumonia contagiosa of the 

 ox there is often oedema of the thoracic walls without actual 

 hydrothorax. 



Pleurisy may be either double or single ; generally it is 

 single, and confined to the right side. 



Pleurisy is sometimes, but very rarely, caused by direct 

 violence to the thoracic walls. Pleurisy is often secondary to 

 other diseases, such as septic broncho-pneumonia — the transit 

 or corn-stalk disease of American cattle — and of many forms of 

 blood poisoning. 



SYMPTOMS. 



The disease at the outset is characterised by some degree of 

 rigor, very often a mere chill, manifested by a staring coat, 

 and coldness of the surface of the body. This is, however, 

 succeeded by signs of pain, often mistaken for colic, during 

 which the horse paws, and perhaps lies down and rolls ; it 

 eventually becomes stiff and sore, and if suddenly approached, 

 or if rapped upon the affected side, will groan. The acts of 

 respiration are performed rapidly and incompletely, the ribs are 

 fixed, the respiration is mostly abdominal, and a hollow line 

 extends along the inferior border of the false ribs, from the 

 sternum across the flank to the anterior spine of the ilium. A 

 dry, short, painful cough supervenes ; the pulse is hard and quick. 

 If the side be closely examined, the muscles covering the affected 

 part will be noticed to tremble or quiver ; this lasts but a short 

 time only, and is succeeded by diminished motion. These signs, 

 as well as the pain upon pressure, indicate that the intercostal 

 muscles participate in the inflammation, and that pleurisy is 

 generally associated with pleurodynia, first described by Haycock. 



When the pleurodynia, or inflammation of the muscles, is very 

 intense the animal moves in a very rigid manner, steps slowly 

 and very short ; is greatly dejected, the back is arched, the skin 

 exhibits great tenderness when subjected to pressure. I may 

 state that I have seen some cases that were so stiff and sore as to 

 fall when compelled to move. 



Hydrothorax. — When an animal dies of pleurisy, especially if 

 it has survived the first stage, a considerable amount of effusion 

 of serum will be found, constituting dropsy of the chest, or 

 hydrothorax. In some instances a large quantity may be found 

 in a day or two, and in some rare cases without any perceptible 



