Table 1.
Bone traits of the radius in 73-week-old laying hens subjected to different rearing and adult housing systems as measured by quantitative computed tomography.
| Density mg/cm3 (±SE) | Cross-sectional area mm2 (±SE) | Bone mineral content mg/mm (±SE) | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Total | Cortical | Trabecular | Total | Cortical | Trabecular | Total | Cortical | Trabecular | ||
| Rearing 1 | ||||||||||
| Conv | 730.1 (16.74) | 990.5 (7.85) | 223.9 (7.72) | 5.8 (0.12) | 3.9 (0.14) | 1.9 (0.12) | 4.2 (0.15) | 3.9 (0.14) | 0.44 (0.03) | |
| Avi | 616.7 (17.50) | 910.6 (8.35) | 220.8 (8.11) | 7.6 (0.12) | 4.5 (0.15) | 3.1 (0.13) | 4.7 (0.15) | 4.1 (0.15) | 0.65 (0.03) | |
| DF | 114 | 114 | 113 | 114 | 114 | 114 | 114 | 114 | 114 | |
| F-value | 40.14 | 64.30 | 0.12 | 181.90 | 17.30 | 45.63 | 16.52 | 2.76 | 23.89 | |
| P-Value | <0.001 | <0.001 | 0.727 | <0.001 | <0.001 | <0.001 | <0.001 | 0.099 | <0.001 | |
| Adult housing 2 | ||||||||||
| FC-L | 708.5 (17.78)a | 962.2 (8.54) | 237.3 (8.27)a | 6.6 (0.13) | 4.4 (0.14) | 2.2 (0.14) | 4.6 (0.16) | 4.2 (0.15)a | 0.50 (0.03) | |
| FC-S | 653.6 (22.77)b | 947.6 (11.62) | 217.4 (10.91)b | 6.8 (0.17) | 4.1 (0.18) | 2.7 (1.9) | 4.3 (0.18) | 3.9 (0.18)a,b | 0.58 (0.05) | |
| CC | 658.2 (17.14)b | 941.8 (8.07) | 212.5 (7.94)b | 6.7 (0.12) | 4.1 (0.14) | 2.6 (0.13) | 4.3 (0.15) | 3.9 (0.15)b | 0.56 (0.03) | |
| DF | 114 | 114 | 113 | 114 | 114 | 114 | 114 | 114 | 114 | |
| F-value | 4.50 | 2.02 | 3.73 | 0.33 | 2.35 | 3.01 | 3.05 | 3.61 | 1.14 | |
| P-Value | 0.013 | 0.137 | 0.027 | 0.717 | 0.100 | 0.053 | 0.051 | 0.030 | 0.323 | |
| Interaction R*A 3 | ||||||||||
| Conv * FC-L | 760.1 (23.39) | 998.5 (12.03) | 243.1 (11.25) | 5.6 (0.17) | 3.9 (0.19) | 1.7 (0.20) | 4.3 (0.19) | 3.9 (±0.19) | 0.38 (0.05) | |
| Conv * FC-S | 708.1 (27.07) | 995.8 (14.18) | 214.4 (13.12) | 5.7 (0.20) | 3.7 (0.21) | 2.1 (0.24) | 4.0 (0.21) | 3.7 (±0.21) | 0.45 (0.06) | |
| Conv * CC | 722.2 (21.18) | 977.1 (10.63) | 214.4 (10.21) | 5.9 (0.15) | 3.9 (0.17) | 2.0 (0.17) | 4.2 (0.18) | 3.9 (±0.17) | 0.49 (0.04) | |
| Avi * FC-L | 656.9 (21.31) | 925.9 (10.75) | 231.5 (10.15) | 7.6 (0.16) | 4.8 (0.17) | 2.8 (0.18) | 5.0 (0.18) | 4.4 (±0.17) | 0.62 (0.04) | |
| Avi * FC-S | 599.0 (32.76) | 899.3 (17.50) | 220.5 (16.01) | 7.8 (0.25) | 4.4 (0.25) | 3.3 (0.30) | 4.6 (0.25) | 3.9 (±0.25) | 0.71 (0.07) | |
| Avi * CC | 594.2 (21.17) | 906.5 (10.63) | 210.6 (10.06) | 7.5 (0.15) | 4.2 (0.17) | 3.2 (0.17) | 4.4 (0.18) | 3.8 (±0.17) | 0.63 (0.04) | |
| DF | 114 | 114 | 113 | 114 | 114 | 114 | 114 | 114 | 114 | |
| F-value | 0.24 | 0.54 | 0.28 | 1.69 | 2.24 | 0.02 | 2.46 | 1.82 | 0.98 | |
| P-Value | 0.784 | 0.584 | 0.754 | 0.189 | 0.111 | 0.980 | 0.090 | 0.166 | 0.378 | |
a,bWithin a column, for each treatment variable (Adult housing, Interaction R*A), means lacking a common superscript differ (P < 0.05).
1Pullets housed in a conventional rearing system (Conv) or an aviary rearing system (Avi) until 16 wk of age, Flocks 1 to 4.
2Adult hens placed into furnished cage- large (FC-L), furnished cage-small (FC-S), or conventional cages (CC) from 16 to 73 wk of age, Flocks 1 to 4.
3Interaction between rearing housing system and adult housing system.