Table 2.
Comparison of keel bone growth between aviary-reared (Avi) and conventionally-reared (Conv) pullets at 16 wk of age.
| Keel Skeletal Characteristics1 (±SE) | ||||||||
|---|---|---|---|---|---|---|---|---|
| Metasternum2 | Height3 | Area4 | Cartilage5 | Cartilage6 | Keel to Pubic7 | Pubic Gap8 | ||
| Length (mm/kg) | (mm/kg) | (mm2/kg) | Length (mm/kg) | Percentage (%/kg) | (mm/kg) | (mm/kg) | ||
| Rearing | ||||||||
| Conv | 72.3 (1.30) | 25.3 (0.35) | 1097.2 (18.64) | 12.6 (0.92) | 14.4 (1.01) | 33.2 (0.93) | 15.7 (0.65) | |
| Avi | 75.5 (1.29) | 25.1 (0.35) | 1138.3 (18.41) | 16.3 (0.90) | 18.0 (0.91) | 27.5 (0.90) | 15.5 (0.64) | |
| DF | 75 | 75 | 75 | 75 | 75 | 75 | 75 | |
| F-Value | 9.70 | 0.36 | 5.18 | 24.01 | 18.98 | 19.65 | 0.13 | |
| P-Value | 0.003 | 0.552 | 0.026 | <0.001 | <0.001 | <0.001 | 0.717 | |
1All keel bone skeletal characteristics were adjusted for BW.
2Length measured on the dorsal metatsternum surface parallel to the cranial region of the sternal notch ending at the caudal border of the keel metasternum tip.
3Height as measured from the ventral surface of the metasternum to the peak of the Carina apex.
4Area of the keel estimated using the formula for area of a right triangle: Area = (metasternum length × height) × 1/2.
5Cartilage length measured on the dorsal metasternum from the line of distinction between the end of ossified bone tissue and initiation of cartilage tissue to the end of the caudal tip of the keel metasternum.
6Percentage cartilage = (cartilage length/metasternum length) × 100.
7Distance between the caudal tip of the keel metasternum to the tip of the left pubic bone.
8Distance between tips of pubic bones.