Keel Abnormality
Keel abnormalities can only be assessed using the catch and release method. As this is a tactile assessment, experience with live birds is essential for proper training. This training is designed to give the user information on the palpation technique.
The ventral surface of a chicken keel bone can be felt using a palpation technique. When performed properly, this technique should not cause any pain or discomfort to the bird. The keel surface should feel straight and smooth. Keel bones can have both fractures and deviations. Fractures (and healing or healed fractures) will typically feel like a large bump on the sides of the bone, or a separation in the bone. The most common types of deviations will feel like an S-, or C-shaped curve or concavities on the surface of the bone. Any bone that is not straight and smooth is considered to have an abnormality.
The palpation technique is demonstrated in the videos below. The hens in these videos are from a genetic line of birds that exhibit a scaleless mutation. This means they have reduced or no feather coverage naturally. These birds were used for the ease in observing the keel bone. To palpate, run one or two fingers along the ventral ridge of the bone from the top the the bottom (this will allow you to feel concavities in the bone). Then run your fingers along the sides of the keel to feel for curves or fractures of the bone.
The palpation technique is demonstrated in the videos below. The hens in these videos are from a genetic line of birds that exhibit a scaleless mutation. This means they have reduced or no feather coverage naturally. These birds were used for the ease in observing the keel bone. To palpate, run one or two fingers along the ventral ridge of the bone from the top the the bottom (this will allow you to feel concavities in the bone). Then run your fingers along the sides of the keel to feel for curves or fractures of the bone.
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This is a keel bone that has been removed postmortem. The dorsal surface of the bone is the part that is felt during palpation. Here the dorsal surface is smooth and straight, and no abnormalities would be felt during palpation. However, this bone does have a tip fracture denoted by the arrow. You can see the bone curling upward, and this would be felt as a bump at the tip of the bone when palpating.
This keel has a severe deformation on the dorsal surface (left arrow), and would feel like a depression in the bone when palpating. This bone also has several tip fractures (right arrow). This bone would score as having keel abnormalities while palpating. |
Due to the importance of physical touch in assessing keel abnormalities, there is currently no repeatability test for this measure