Diseases of the Hespiratory Organs 177 



the flap of gristle (arytenoid), which is drawn in, valve-like, 

 over the opening by the current of air, cut off. 



Some cases of roaring due to feeding on vetches {La- 

 thyrus Sativa or Cicero) may be cured by changing the 

 feed, and giving some doses of nnx vomica. Otliers due to 

 dropsical effusions appear intermittently and may be bene- 

 fited by tonics and iodide of potassium, with hard, dry feed- 

 ing and exercise. Tumors and other mechanical obstructions 

 must be removed with the knife. 



Finally, roaring is often hereditary in horses with a nar- 

 row space between the jaws and thick, short neck, with badly 

 set on head, and such should be rejected for breeding pur- 

 poses. 



BKONCHITIS. 



Inflammation of the large air-tubes within the lungs. It 

 may be looked vipon as an extension downward of nasal ca- 

 tarrh or sore-throat and frequently supervenes on one or the 

 other of these. Otherwise it owns the same general causes 

 with these affections. It may also attend on influenza, 

 strangles, contagious pleuro-pneumonia, distemper in dogs, 

 tuberculosis, and parasitic diseases of the lungs. 



Sy?npfoms. In mild cases there are dullness, impaired 

 appetite, hot dry mouth, red membrane of nose, accelerated 

 pulse and breathing, and a cough at first hard but becoming 

 soft and rattling as discharge is established from the nose. 

 Such may recover in a few days without treatment. 



In severe cases there is dullness, inappetence, hot dry 

 mouth, increased temperature, rapid pulse, labored breath- 

 ing with loud blowing sounds over the lower end of the wind- 

 pipe and behind the middle of the shoulder-blade. The 

 cough is dry, hard, sonorous, and painful (barking), often 

 occurring in fits and seeming to come from the depth of the 

 chest. Percussion detects no change of resonance at any 

 part of the chest, as in pneumonia. The membrane of the 

 nose has a dark red or violet hue, varying in proportion to 

 the general implication of the bronchial tubes and especial- 

 ly the smaller ones, and there is drowsiness and drooping 

 of the head in the same ratio. 



