REPAIR OF BONE IN THE DOMESTIC FOWL 
B. F. Kaupp, Poultra' Investigator and Pathologist, Animal Industry Division 
Iii presenting this material the work is divided into three groups, as 
follows: 
1. The structure and development of the bones of fowls. 
2. The kinds of fractures and the reparative processes. 
3. Means of controlling the bird and care of the fracture. 
I. The Structure of Bone 
The bones of the domestic fowl may be divided into four classes, as 
follows: long, short, flat, and irregular. 
Long bones are found in the limbs, where they form a system of levers 
to’ sustain the weight of the body and confer the power of locomotion 
upon it. The femur, tibia, and humerus are examples of this class. 
The shaft of the long bone is contracted and narrowed to afford greater 
space for the bellies of the muscles. The extremities generally are 
somewhat expanded for greater convenience of motor connection, for the 
purpose of articulation, and for affording a bony surface for muscular 
attachment. Some long bones are slightly curved, thus affording 
greater strength to them. 
Short bones may be found where a part of the skeleton is intended 
for strength, with its motion slight and limited, and where it is divided 
into a number of small pieces, united by ligaments. Here the separate 
bones are short and compressed. The bones of the toe are examples of 
short bones. 
The patella and the two carpal bones are irregular. 
Flat bones may be found where the principal requirement is extensive 
protection or large bony surface for muscular attachment, osseous struc¬ 
tures expanded into flat bony plates, are found, as in the case of the 
skull and pelvis. In the cranial bones, also, there are layers of compact 
tissue known as tables. The outer table is thick and tough; the inner 
table thinner, denser, and more brittle, and, therefore, termed the vit¬ 
reous table, while the intervening cancellated tissue, which is permeated 
by air spaces, is called diploe. 
Many of the bones of the fowl, as the head, vertebra, and humerus, 
contain air cavities partitioned off by fine bony structures and into 
which cavities the air sacs send extensions. The respiratory apparatus 
of the fowl consists of two lungs, which occupy the upper thoracic 
region, pushing out between the ribs and composed of a series of tubes. 
Some of the bronchi or air tubules communicate with air sacs or blad- 
