Table 6.
The effects of the main factors, their interactions, and the covariates on the results of the bone mineral density (BMD) of the keel bone when hens were kept in cages.
| Effect | BMD (g/cm2) | Effect | BMD (g/cm2) | ||
|---|---|---|---|---|---|
| F Value | p -Value | F Value | p -Value | ||
| Generation (G) | 27.79 | <0.001 | LL × KBF | 0.628 | 0.597 |
| Layer line (LL) | 2.17 | 0.091 | KBD × KBF | 0.441 | 0.644 |
| Keel bone deformity (KBD) | 7.92 | <0.001 | First egg | 0.863 | 0.486 |
| Keel bone fracture (KBF) | 3.52 | 0.061 | LP1 | 2.871 | 0.023 |
| G × LL | 0.702 | 0.552 | LP2 | 6.550 | <0.001 |
| G × KBD | 1.68 | 0.188 | a | 4.58 | 0.001 |
| G × KBF | 2.49 | 0.115 | b | 0.786 | 0.535 |
| LL × KBD | 1.4425 | 0.197 | c | 1.938 | 0.103 |
LP1 = laying performance from 18 to 29 weeks of age. LP2 = laying performance from 30 to 69 weeks of age. Parameters of the Gompertz growth curve: a = adult body weight (g) of the hen at 69 weeks of age (asymptotic limit), b = slope of the curve, c = point of inflection (weeks).