Table 1.
Neurochemical concentrations in chicken cecal luminal content and tissue
| Neurochemical | Timepoint (d of age) |
||||
|---|---|---|---|---|---|
| 3 d | 7 d | 9 d | 21 d | ||
| Norepinephrine | |||||
| Tissue | Control | 1.17 ± 0.08 | 1.46 ± 0.10 | 2.10 ± 0.13 | 1.74 ± 0.15 |
| Cold stress | 1.26 ± 0.14 | 1.68 ± 0.20 | 2.58 ± 0.14 | 2.19 ± 0.32 | |
| Luminal content | Control | NM | 1.08 ± 0.37 | 2.19 ± 0.92 | 0.75 ± 0.18* |
| Cold stress | NM | 1.35 ± 0.48 | 0.85 ± 0.15 | 12.98 ± 4.26 | |
| Dopamine | |||||
| Tissue | Control | 0.19 ± 0.01 | 0.30 ± 0.04 | 0.31 ± 0.01 | 0.17 ± 0.01 |
| Cold stress | 0.18 ± 0.02 | 0.29 ± 0.04 | 0.29 ± 0.01 | 0.15 ± 0.01 | |
| Luminal content | Control | NM | 0.32 ± 0.02 | 0.33 ± 0.03* | 0.06 ± 0.04* |
| Cold stress | NM | 0.23 ± 0.02 | 0.15 ± 0.03 | 0.23 ± 0.03 | |
| Serotonin | |||||
| Tissue | Control | 8.34 ± 0.53 | 12.28 ± 1.34 | 10.16 ± 1.02* | 6.69 ± 0.70 |
| Cold stress | 8.28 ± 0.65 | 11.49 ± 0.77 | 37.02 ± 3.17 | 5.61 ± 0.71 | |
| Luminal content | Control | NM | 0.54 ± 0.11 | 0.57 ± 0.07 | 1.87 ± 0.57* |
| Cold stress | NM | 0.39 ± 0.05 | 0.23 ± 0.01 | 0.79 ± 0.07 | |
| 5-HIAA | |||||
| Tissue | Control | 0.25 ± 0.01 | 0.37 ± 0.02 | 0.52 ± 0.03* | 0.29 ± 0.01 |
| Cold stress | 0.28 ± 0.02 | 0.43 ± 0.07 | 0.71 ± 0.06 | 0.25 ± 0.02 | |
| Luminal content | Control | NM | 0.03 ± 0.03 | 0.64 ± 0.18 | 1.85 ± 1.15 |
| Cold stress | NM | 0.32 ± 0.26 | 0.28 ± 0.08 | 0.16 ± 0.16 | |
| Histamine | |||||
| Tissue | Control | 5.37 ± 0.25 | 7.47 ± 0.61 | 7.77 ± 0.59* | 8.13 ± 1.07 |
| Cold stress | 5.26 ± 0.26 | 6.41 ± 0.49 | 11.07 ± 0.83 | 7.88 ± 0.36 | |
| Luminal content | Control | NM | 6.01 ± 1.14 | 6.75 ± 1.72 | ND |
| Cold stress | NM | 6.86 ± 1.28 | 8.09 ± 0.32 | 1.07 ± 0.73 | |
Abbreviations: NM, not measured; ND, not detected; 5-HIAA, 5-hydroxyindoleacetic acid.
Values are μg of neurochemical per g of tissue or luminal content. All values are expressed as mean ± SEM (n = 10 chickens/group/timepoint). Chickens were (cold stress) or were not (control) subjected to ambient environmental cold stress on 4, 5, and 6 d of age and then sacrificed on either 7, 9, or 21 d of age as described in the Methods section. Data was analyzed using 2-way ANOVA followed by Sidak's post-hoc test.
Significant difference (P < 0.05) of control tissue or luminal content compared to respective cold stress group tissue or luminal content in same column (e.g. control tissue norepinephrine vs cold stress tissue norepinephrine, or control luminal content norepinephrine vs cold stress luminal content norepinephrine).