ULCERATIVE DISEASE OF THE HOCK-JOINT. 253 
The post-mortem appearances have been so fully and ably 
described by Dr. Taylor, in your Journal for March, that I 
have nothing to add to that part of my subject. 
I repeat, I have no doubt of salt often causing the death 
of pigs, when given to them in excess, and think the fact 
cannot be given too great publicity to, so that the owners of 
these animals may be aw r are of the danger of using it at all. 
It is on this account I have recorded the above cases. 
ULCERATIVE DISEASE OF THE HOCK-JOINT. 
By R. H. Dyer, M.R.C.V.S., Waterford. 
The subject of this case was an aged horse, of the cart- 
breed. He had met with an accident and was destroyed. 
Having known him to have a very considerable quantity of 
ossific matter deposited upon the near hock, and being lame 
in consequence, I was desirous of examining the cavity of 
the joint, more especially as the carter informed me the 
animal disliked any one to touch that part of the leg in the 
act of grooming, it being always sore. 
Inspection .—All the bones comprising the joint are grown 
together, so that no two bones can in any way be separated , so 
much bony matter has been thrown out. The inner small 
metatarsal bone adheres to the large one, five inches from 
above downwards, by means of bony matter. This fact 
accounts for the stiff movement of the limb. On prosecuting 
the examination, I find the inferior extremity of the tibia 
to present the following appearance : the middle projection 
ulcerated, extending to the bottom of the outer groove, and 
to the bottom of the inner groove also, and nearly up to the 
top of this projection. Portions of the articular cartilage 
entirely removed by absorption. The astragalus: the outer 
prominence much inflamed, just at its middle. The inner 
has a deep pit scooped out by the ulcerative process, a 
trough large enough to bury half of a good-sized pea. In the 
bottom of the groove, in its centre, absorption from ulcera¬ 
tion has also taken place. 
This brief account of ulceration of the hock-joint will 
perhaps be sufficient for the purpose of reflection. What 
was the cause of the ulceration ? Was the bony matter 
thrown out first, and the ulcerative process excited by the 
state of the joint? In looking at the anatomy of the joint, 
