Various Causes of Noisy Respiration. 17 



as the effects of tracheotomy, are far from being a rare cause 

 of noise production. 



Pressure on, or inflammation or destruction of, the re- 

 current nerves, which supply nearly all the muscles of the 

 larynx, will certainly quickly induce that kind of roaring 

 which is so common among horses, and which will receive 

 most notice in this treatise. Of course, the same result 

 occurs if the main trunks — the pneumogastrics — which give 

 off these nerves are involved in disease or injury, whether 

 at their point of origin in the medulla oblongata, or at any 

 part of their course from the cranium to the cavity of the 

 chest. This will be noticed hereafter. 



Certain kinds of food will produce Roaring, and perhaps 

 the most notorious for causing difficult and stridulous 

 breathing, which may terminate in asphyxia if relief be not 

 promptly afforded by the operation of tracheotomy, is the 

 Indian vetch or pea commonly known in this countrj' as 

 Indian " mutters," obtained from the Lathyrus sativus. 

 Several remarkable instances of poisoning with this legumen 

 are recorderl.^ In France another kind of vetch known as 

 ''Gesse-'chiche,'' -Jarat, Jarosse" (the flat-podded latyrus — ■ 

 Lathyrus cicera) is reported to have caused a similar 

 accident, the noise and distress being most' evident wheij 

 the horses were put to even slight exercise.^ 



According to Grognier,^ such accidents are somewhat 

 frequent, this plant being grown in the South of France for 

 the food of sheep while they are housed in winter. Dela- 

 fond and Renault, as well as Verrier,* give interesting 

 notices of cases of this kind. One is to the effect that a 

 farmer in the neighbourhood of Paris kept his horses on 

 winter tares, chopped and mixed with a small quantity of 



^ See the " Veterinary Journal " for April, 1885 (p. 233), and July, 

 1886 (p. 337). 



^ " Kecueil de Med. Veti^rinaire," 1883; "Nouveau Dictionnaire 

 Pratique de Med., etc., Veterinaires," tome iv., p. 362. 



3 "Cours d'Hygiene," p. 174. 



* "Etude sur la Gesse-chiche," Rouen, 1869. 



9 



