388 DADD’S VETERINARY MEDICINL AND SURGERY 
tlosed through constriction in its centre, tho.gh, when open, issu 
ing a mucous and sanious matter, especially at such time as the 
animal is straining afresh. The circumflex action of the sphincter 
ani around the neck of the swelling, together with ‘+s distension 
with gas, aud the action of the air upon its surface, all add to its 
increase of volume and change of color; while the straining, at the 
same time increases the difficulty of any effort the practitioner 
may make toward effecting a return of the protruded gut. With 
its augir¢ntation of volume comes a deepening redness, turning, 
thrcuy) the constriction of the sphincter, to a darker, and even 
purp'e hue, the membrane becoming, at the same time, inflated 
and swollen, and gradually changing its color from red to yeliow 
and to brown, though still having a humid shining aspect, now 
becoming glairy from albuminous secretion, which is not only 
mucous, but at times purulent. 
Causes.—These may be summed up in irritation, either direct 
or sympathetic, of the mucous membrane lining the anus and 
rectum. It is possible that prolonged constipation, from giving 
rise to violent straining efforts at expulsion of dry and hardened 
feces, might briug it on, or even the strains of parturition. The 
action produced by excessive purgation may canse it, but more 
especially irritation of a mechanical kind, arising from direct in- 
jury to the membrane or rectum during the operation of raking 
or manual exploration of the gut, or of clystering. It may prove 
an accompaniment of an enteritic, colicky, or diarrheal condition 
of bowel. It is possible it may ensue on nicking, though I never 
knew it to follow that operation. Violent struggles of any kind, 
as in such a case as is mentioned in the ‘ Veterinarian,’ by Mr. J. 
Brown, V.S., London, wherein the horse ‘had forced out nearly 
a foot of the rectum in struggling violently to release himself, 
while being cast. 
Treatment.—The formidable, and indeed awful, aspect of this 
disease is apt to operate in the mind of the owner of the animal 
favorably for the veterinary surgeon, inasmuch as it gives rise to 
his being called to the case sooner than he otherwise would have 
leen. Should the summons be an early one, at the time that 
the protrusion is recent, and its volume nothing so very alarming, 
‘udicious exercise of the taxis, if employed at the moment, may 
iucceed in the return of the gut. Distributing the fingers of both 
hands over the wrinkled and swollen body of the protrusion 
