16 
The Bulletin 
days standing. This fracture, if allowed to remain in this condition, 
would have made a vicious union and a deformed limb, which in a show 
bird is a serious defect. 
Figure 9 shows a fracture six days standing and Figure 10 is a 
rontgengraph of the same fracture at nine days standing. It will be 
noticed that the callus is becoming more dense, due to the increased 
molecular density brought about by the reparative process. Figure 11 
shows the same fracture twelve days standing. 
Figure 12 shows a plaster of Paris cast which was used on case JSTo. 
15. These casts are rather heavy for birds. 
Figure 13 shows a fracture with adjustment and appliance in place. 
This is a fracture of a tibia in a three-pound Single-Comb Bhode Island 
Red pullet. The appliance consisted of cotton, wooden splints, one-inch 
cotton bandage, and glue. Glue has proven the most satisfactory in the 
experience of this laboratory. 
Figure 14 is the last of the series of twenty-one birds studied. A 
shows a normal shank and B a vicious union, with deformity. This 
is similar to numbers 3 and 4 in Figure 3. It was a Buff Plymouth Rock 
cock, which was rendered blemished for show purposes due to improper 
care of the fracture. 
In one case where the hones of the wing were not in perfect apposi¬ 
tion, and not securely held, the bird was handled often and the ends 
of the hone moved frequently, there was found a few islands of cartilage. 
This was not observed where the broken ends of bone were firmly held 
in proper position. 
Summary 
A series of twenty-one cases of fractures were studied in the domestic 
fowl. It was found that at the end of the fifth day islands of bone tissue 
had begun to form. 
The repair of fractures in the domestic fowl is intramembranous. 
The periosteal, endosteal, and intermediary calluses show hone forma¬ 
tion in trabecular-like arrangement. 
By the end of the thirteenth day the major portion of the bone tissue 
had formed and was found completed before the twentieth day. 
The appliance used to hold the broken bones in apposition in the 
domestic fowl may be removed with safety by the end of the twelfth or 
thirteenth day. 
The structure of compact bone in the domestic fowl is similar to that 
of mammalia. 
