Diseases of the Digestive System. 187 
silver are recommended, the mouth being kept open by - 
means of the gag. 
Choking.—Notwithstanding ample provision in the 
dog for bolting the food, this accident sometimes 
takes place, the usual seat of obstruction being the 
entrance to the pharynx. The Symptoms are frequent 
attempts to regurgitate or force out the obstruction ; 
fluids passed into the mouth return immediately. There 
is also frequent cough, profuse salivation, great discom- 
fort, an anxious look in the eyes, and sometimes the 
obstruction may be seen and felt on the outside. 
Treatment.—Previous to actual surgical interference 
the nature of the obstruction should be ascertained, as 
sharp or angular substances are sometimes serious 
offenders, and should not be pushed downwards. A 
whalebone probe or a flexible tube specially made for 
the purpose will answer for pressing down a piece of 
meat, pudding, &c., but when bones or other hard and 
dangerous things are lodged in the passage, the throat 
forceps alone are useful, by which the body is seized and 
drawn through the mouth.. During the operation the 
dog must be fixed securely, and the mouth held open by 
the gag. ‘These methods may fail in consequence of the 
offending substance moving downwards and again re- 
tained within the gullet. In this case, seeing no direct 
possibility of moving the obstruction any further, the 
surgeon will not hesitate to open the gullet by incision 
from the outside, as experience shows the surprising 
aptitude for healing in the portions subjected to the 
operation. A fluid diet and attention to the wound 
comprise the after-essentials for a week or more. 
Stricture of the Gullet is the probable result of 
repeated choking, considerable injury. to the mucous 
membrane and even the muscular layer, arising from the 
swallowing of hard, and probably sharp, angular sub- 
stances, as bones, &c. Similar states are also due to the 
presence and burrowing of a small round worm known as 
filaria sanguinolenta. 
The Symptoms are frequent and usually slight attacks 
of choking, which subside without treatment, or otherwise, 
