Table 4.
Comparison of bone breaking strength in adult laying hens at 73 wk of age.
| Maximum bone breaking strength (kg) | ||||
|---|---|---|---|---|
| Humerus (±SE) | Radius (±SE) | Tibia (±SE) | ||
| Rearing1 | ||||
| Conv | 9.2 (0.45) | 5.1 (0.13) | 14.1 (0.75) | |
| Avi | 6.3 (0.44) | 5.1 (0.12) | 14.4 (0.75) | |
| DF | 40 | 57 | 57 | |
| F-Value | 34.6 | 0.05 | 0.59 | |
| P-Value | <0.001 | 0.816 | 0.445 | |
| Adult housing2 | ||||
| FC-L | 7.7 (0.48) | 5.2 (0.14) | 14.8 (0.76)a | |
| FC-S | 7.4 (0.55) | 5.2 (0.17) | 14.4 (0.78)a | |
| CC | 8.1 (0.49) | 5.1 (0.18) | 13.5 (0.77)b | |
| DF | 40 | 57 | 57 | |
| F-value | 0.56 | 0.11 | 5.59 | |
| P-value | 0.566 | 0.893 | 0.006 | |
| Interaction R*A3 | ||||
| Conv * FC-L | 9.2 (0.62) | 5.1 (0.18) | 14.4 (0.82) | |
| Conv * FC-S | 9.6 (0.74) | 5.1 (0.19) | 14.6 (0.85) | |
| Conv * CC | 8.7 (0.62) | 5.1 (0.17) | 13.3 (0.81) | |
| Avi * FC-L | 6.3 (0.62) | 5.2 (0.17) | 15.2 (0.81) | |
| Avi * FC-S | 5.3 (0.69) | 5.2 (0.18) | 14.2 (0.83) | |
| Avi * CC | 7.5 (0.65) | 5.1 (0.18) | 13.7 (0.82) | |
| DF | 40 | 57 | 57 | |
| F-value | 3.1 | 0.07 | 0.99 | |
| P-value | 0.058 | 0.929 | 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, Flock 1 to 4.
3Interaction between rearing housing system and adult housing system.