Table 2.
Feed intake and growth rate of hens. (a) Feed intake of hens of different genotypes (g per kg body weight per week) (mean ± SEM); (b) growth rate (g/day) for Period A (Weeks 1 to 4), Period B (Weeks 5 to 7), and Period C (Weeks 8 to 11) (lsmean ± SEM, N = 257).
| (a) | ||||
| Age (Week) | W/W (n = 6) | W/D (n = 6) | D/D (n = 6) | p-Value |
| 0–1 | 1736.5 ± 71.23 | 1916.2 ± 59.24 | 1888.0 ± 54.05 | n.s. |
| 1–2 | 1691.7 ± 40.55 | 1688.8 ± 49.04 | 1676.8 ± 43.53 | n.s. |
| 2–3 | 1343.8 ± 26.60 | 1455.5 ± 42.27 | 1386.3 ± 32.11 | n.s. |
| 3–4 | 1139.9 ± 16.58 | 1237.7 ± 35.84 | 1183.2 ± 28.14 | n.s. |
| 4–5 | 919.1 b ± 21.05 | 975.0 a,b ± 31.39 | 1016.2 a ± 16.11 | <0.05 |
| 5–6 | 833.9 b ± 15.92 | 888.0 a,b ± 26.29 | 904.5 a ± 13.68 | <0.05 |
| 6–7 | 730.6 b ± 12.15 | 745.8 a,b ± 10.72 | 779.0 a ± 11.62 | <0.05 |
| 7–8 | 678.2 ± 6.87 | 683.4 ± 3.78 | 689.9 ± 7.12 | n.s. |
| 8–9 | 565.0 ± 7.15 | 566.9 ± 9.85 | 583.4 ± 12.91 | n.s. |
| 9–10 | 595.5 ± 8.72 | 575.1 ± 4.57 | 577.1 ± 12.68 | n.s. |
| 10–11 | 596.5 ± 3.71 | 598.9 ± 8.93 | 596.2 ± 7.55 | n.s. |
| (b) | ||||
| Period 1 | W/W | W/D | D/D | p-Value |
| A | 6.13 ± 0.09 | 6.30 ± 0.09 | 6.20 ± 0.09 | n.s. |
| B | 8.50 b ± 0.15 | 9.44 a ± 0.15 | 9.78 a ± 0.15 | <0.001 |
| C | 8.32 ± 0.17 | 8.74 ± 0.17 | 8.90 ± 0.17 | n.s. |
W: wild-type 5-HTT genotype; D: variant 5-HTT genotype with a 4 base deletion (AATT) and one base change (A → T) in the 5′-flanking region; n: number of independent groups (data points), each consisting of 15 hens; N: number of independent data points, each consisting of one individual hen; 1 The periods were defined post hoc as the period before, during, and after significant genotype differences in feed intake (see (a)); a,b Means and lsmeans in a row with no common superscript letter differ significantly (p < 0.05); n.s.: not significant.