Table 2.
Biological observations of sampled chicks (±SE).
| Sample group | E < 30 | E30+ | L < 30 | P |
|---|---|---|---|---|
| Initial egg weight (g) | 65.84 (±0.57) | 65.98 (±0.63) | 66.92 (±0.81) | 0.526 |
| Chick weight(g) | 45.73a (±0.6) | 43.28b (±0.51) | 45.97a (±0.72) | 0.002 |
| Yolk-free body weight (g) | 39.08 (±0.46) | 39.44 (±0.46) | 40.15 (±0.61) | 0.426 |
| Chick length (cm) | 19.12b (±0.11) | 19.77a (±0.09) | 19.67a (±0.2) | 0.007 |
| Femur whole bone weight (mg) | 259 (±5.2) | 263 (±4.7) | 273 (±6.2) | 0.678 |
| Femur water weight (mg) | 190 (±4.1) | 195 (±0.3.6) | 202 (±4.7) | 0.632 |
| Femur organic weight (mg) | 52.9 (±1.1) | 53.4 (±1.0) | 55.1 (±1.3) | 0.794 |
| Femur mineral weight (mg) | 16.1 (±0.2) | 15.5 (±0.3) | 16.1 (±0.3) | 0.695 |
| Femur bone ash % | 24.8a,b (±2.5) | 22.9b (±3.3) | 25.5a (±3.5) | 0.013 |
| Serum Ca (mmol/L) | 2.32 (±0.03) | 2.35 (±0.02) | 2.27 (±0.03) | 0.088 |
| Serum P (mmol/L) | 1.82a (±0.05) | 1.75a,b (±0.03) | 1.65b (±0.05) | 0.041 |
| Yolk weight (g) | 6.77a (±0.23) | 3.85c (±0.18) | 5.82b (±0.24) | <0.001 |
| Yolk water content (g) | 3.51a (±0.11) | 2.1c (±0.09) | 3.05b (±0.11) | <0.001 |
| Yolk solids (g) | 3.26a (±0.13) | 1.75c (±0.1) | 2.77b (±0.14) | <0.001 |
| PCV | 31.6 (±0.78) | 30.0 (±0.5) | 29.9 (±0.68) | 0.174 |
a,b,cMeans within a row with different letter superscripts differ significantly (P < 0.05).
Abbreviations: E < 30, chicks that hatched by ≤ 486 h of incubation, with a sojourn in the hatcher tray of less than 30 h; E30+, chicks that hatched by ≤ 486 h of incubation, with a sojourn in the hatcher tray of between 30 and 48 h; L < 30, chicks that hatched from >486 until 516 h of incubation, with a sojourn in the hatcher tray of less than 30 h.