144 
OBSERVATIONS ON SOUNDNESS. 
first would in that case generally suffice for all, although 
some of them undergo much greater changes than others, 
depending upon their magnitude as well as their situation. 
A bursa is described as a small synovial sac, found in the 
vicinity of joints and tendinous sheaths, which secretes a 
fluid in every way analogous to that found within a true 
joint, and which is termed synovia. Indeed, many of these 
bursae are actually in direct communication with the interior 
of a joint. Their use is supposed to be that of preventing 
friction, concussion, &c., of parts; and being placed between 
structures, they will naturally have such a tendency, the oil¬ 
like fluid which they contain being admirably adapted for that 
purpose. When, however, disease is set up, and the bursae 
become enlarged or swollen, inconvenience and sometimes 
lameness result therefrom. This is not of necessity the case. 
Numerous causes have been assigned for the commence¬ 
ment of a bursal tumour, viz., work, sprain, and others, as 
active agents in promoting disease. Doubtless, concussion 
is the principal one, whether in youth or adult age. It has 
been declared that a colt, not having been broken, cannot 
have bursal enlargements through work or a sprain. It does 
not follow as a matter of course, because an animal has not 
been trained or put to work, that the disease which we are 
considering is not caused by over-work or sprain. How 
frequently do we witness colts exerting themselves in mere 
play beyond their powers and strength ? The most marked 
case in proof of this assertion—I could relate many— 
occurred in my practice a few T months since. A M.D. re¬ 
quested me—he is a great horse amateur—to call at his 
stables and look at a twm-year-old colt, which had what he 
termed a bog- or blood-spavin. I found on the off hock an 
immense swelling of a bursal sac, w 7 hich w 7 as much inflamed 
and extremely sensitive; and although the colt could not be 
pronounced lame, still the action of the joint was impaired. 
Various were the inquiries instituted as to the work he had 
performed, to all of which replies were given in the negative. 
I, however, found out that the colt spent the greater part of 
his time in a low, small-sized loose box, and to amuse himself 
he was in the habit of making attacks upon the rafters, to 
accomplish which he stood upon his hind feet and struck out 
with the front. This amusement caused tumefaction of the 
bursa before mentioned, and converted a two-hundred guinea 
colt into a comparatively valueless animal. 
Thus, it will be seen that actual work, or the process of 
training, is not absolutely necessary to produce disarrange¬ 
ment of these sacs. 
