Osteoporosis and Bony Enlargements 227 
OSTEOPOROSIS 
This is a disease of horses, and is commonly known 
as “big head.” In some regions it is rather prevalent, 
while in other regions it is rarely seen. This fact is 
explained by the presence or absence in the soil, water 
or food of some substance which is important in the 
growth and nutrition of bone. The disease is probably 
associated with the salts of lime. 
Osteoporosis is an absorption and softening of the 
bony structure. The bone becomes increased in size, 
but lighter in weight, and very porous or spongy. The 
disease is usually first observed in the bones of the 
head. The bones of the face become enlarged, giving 
the face a full, rounded appearance. The lower jaw- 
bones become enlarged; later, the legs are affected. 
The bones may be slightly inflamed, somewhat tender 
upon manipulation, and locomotion may be interfered 
with. As the disease progresses, the animal falls away 
rapidly in flesh. 
The treatment for this trouble consists in the use 
of tonie medicines, combined with a variety of nour- 
ishing foods, and hygienic surroundings. Once the 
disease is well established, treatment is of little avail. 
BONY ENLARGEMENTS 
Bony bunches, or enlargements, are technically known 
as “exostoses.” They may occur at any point on a bone, 
but are most frequently found and are most serious in 
the region of a joint. An exotosis, “or bony bunch,” is 
