. | . | . | Acclimation II . | . | . | |
---|---|---|---|---|---|---|
. | Initial . | Acclimation I . | [TaccI→TaccII (°C)] . | . | Acclimation II (pooled) . | |
Tacc=10°C | ||||||
Mb (g) | 91.8±3.5 (10) | 91.6±5.0 (10) | [22→10] | 103.9±7.2 (5) | 93.6±4.6 (10) | |
[35→10] | 94.4±5.7 (5) | |||||
Tlc (°C) | 29.1±1.4(15)* | 30.0±1.6 (10) | [22→10] | 34.0±1.5 (5) | 33.2±1.0 (10) | |
[35→10] | 32.5±1.0 (5) | |||||
Tb (°C) | 38.4±0.1 (8) | 40.5±1.0 (9) | [22→10] | 40.2±1.6 (5) | 39.2±0.8 (8) | |
[35→10] | 38.2±0.9 (5) | |||||
Cmin (mW g−1 °C−1) | 0.901±0.084 (8) | 0.704±0.063 (9) | [22→10] | 0.806±0.260 (5) | 0.925±0.160 (8) | |
[35→10] | 1.043±0.141 (5) | |||||
BMR (W) | 0.762±0.066 (10) | 0.665±0.058 (10) | [22→10] | 0.660±0.069 (5) | 0.661±0.053 (10) | |
[35→10] | 0.662±0.085 (5) | |||||
Tacc=22°C | ||||||
Mb (g) | 95.8±5.3 (10) | 97.5±4.0 (10) | [10→22] | 96.3±6.8 (5) | 93.6±4.5 (10) | |
[34→22] | 90.1±7.2 (5) | |||||
Tlc (°C) | 29.1±1.4(15)* | 29.8±1.9 (9) | [10→22] | 30.7±1.7 (5) | 31.6±1.6 (10) | |
[35→22] | 32.5±2.6 (5) | |||||
Tb (°C) | 37.9±0.6 (5) | 39.8±0.1 (10) | [10→22] | 38.8±1.1 (5) | 39.0±0.9 (7) | |
[35→22] | 37.4±1.5 (5) | |||||
Cmin (mW g−1 °C−1) | 1.204±0.184 (5) | 1.211±0.351 (10) | [10→22] | 0.891±0.164 (4) | 0.857±0.101 (7) | |
[35→22] | 1.043±0.141 (3) | |||||
BMR (W) | 0.762±0.056 (10) | 0.612±0.039 (10) | [10→22] | 0.626±0.059 (5) | 0.600±0.042 (10) | |
[35→22] | 0.575±0.056 (5) | |||||
Tacc=35°C | ||||||
Mb (g) | 90.4±4.8 (10) | 94.5±4.1 (10) | [10→35] | 91.0±6.8 (5) | 99.2±5.3 (10) | |
[22→35] | 96.3±6.1 (5) | |||||
Tlc (°C) | 29.1±1.4(15)* | 32.4±1.9 (9) | [10→35] | 31.4±3.9 (5) | 32.7±2.1 (10) | |
[22→35] | 33.9±1.6 (5) | |||||
Tb (°C) | 38.3±0.4 (10) | 38.9±1.4 (8) | [10→35] | 38.2±1.2 (5) | 38.8±0.7 (10) | |
[22→35] | 39.1±1.1 (5) | |||||
Cmin (mW g−1 °C−1) | 0.871±0.094 (10) | 0.876±0.222 (8) | [10→35] | 0.778±0.143 (4) | 0.854±0.172 (8) | |
[22→35] | 0.930±0.320 (4) | |||||
BMR (W) | 0.757±0.073 (10) | 0.546±0.039 (10) | [10→35] | 0.566±0.089 (5) | 0.557±0.049 (10) | |
[22→35] | 0.549±0.053 (5) |
. | . | . | Acclimation II . | . | . | |
---|---|---|---|---|---|---|
. | Initial . | Acclimation I . | [TaccI→TaccII (°C)] . | . | Acclimation II (pooled) . | |
Tacc=10°C | ||||||
Mb (g) | 91.8±3.5 (10) | 91.6±5.0 (10) | [22→10] | 103.9±7.2 (5) | 93.6±4.6 (10) | |
[35→10] | 94.4±5.7 (5) | |||||
Tlc (°C) | 29.1±1.4(15)* | 30.0±1.6 (10) | [22→10] | 34.0±1.5 (5) | 33.2±1.0 (10) | |
[35→10] | 32.5±1.0 (5) | |||||
Tb (°C) | 38.4±0.1 (8) | 40.5±1.0 (9) | [22→10] | 40.2±1.6 (5) | 39.2±0.8 (8) | |
[35→10] | 38.2±0.9 (5) | |||||
Cmin (mW g−1 °C−1) | 0.901±0.084 (8) | 0.704±0.063 (9) | [22→10] | 0.806±0.260 (5) | 0.925±0.160 (8) | |
[35→10] | 1.043±0.141 (5) | |||||
BMR (W) | 0.762±0.066 (10) | 0.665±0.058 (10) | [22→10] | 0.660±0.069 (5) | 0.661±0.053 (10) | |
[35→10] | 0.662±0.085 (5) | |||||
Tacc=22°C | ||||||
Mb (g) | 95.8±5.3 (10) | 97.5±4.0 (10) | [10→22] | 96.3±6.8 (5) | 93.6±4.5 (10) | |
[34→22] | 90.1±7.2 (5) | |||||
Tlc (°C) | 29.1±1.4(15)* | 29.8±1.9 (9) | [10→22] | 30.7±1.7 (5) | 31.6±1.6 (10) | |
[35→22] | 32.5±2.6 (5) | |||||
Tb (°C) | 37.9±0.6 (5) | 39.8±0.1 (10) | [10→22] | 38.8±1.1 (5) | 39.0±0.9 (7) | |
[35→22] | 37.4±1.5 (5) | |||||
Cmin (mW g−1 °C−1) | 1.204±0.184 (5) | 1.211±0.351 (10) | [10→22] | 0.891±0.164 (4) | 0.857±0.101 (7) | |
[35→22] | 1.043±0.141 (3) | |||||
BMR (W) | 0.762±0.056 (10) | 0.612±0.039 (10) | [10→22] | 0.626±0.059 (5) | 0.600±0.042 (10) | |
[35→22] | 0.575±0.056 (5) | |||||
Tacc=35°C | ||||||
Mb (g) | 90.4±4.8 (10) | 94.5±4.1 (10) | [10→35] | 91.0±6.8 (5) | 99.2±5.3 (10) | |
[22→35] | 96.3±6.1 (5) | |||||
Tlc (°C) | 29.1±1.4(15)* | 32.4±1.9 (9) | [10→35] | 31.4±3.9 (5) | 32.7±2.1 (10) | |
[22→35] | 33.9±1.6 (5) | |||||
Tb (°C) | 38.3±0.4 (10) | 38.9±1.4 (8) | [10→35] | 38.2±1.2 (5) | 38.8±0.7 (10) | |
[22→35] | 39.1±1.1 (5) | |||||
Cmin (mW g−1 °C−1) | 0.871±0.094 (10) | 0.876±0.222 (8) | [10→35] | 0.778±0.143 (4) | 0.854±0.172 (8) | |
[22→35] | 0.930±0.320 (4) | |||||
BMR (W) | 0.757±0.073 (10) | 0.546±0.039 (10) | [10→35] | 0.566±0.089 (5) | 0.557±0.049 (10) | |
[22→35] | 0.549±0.053 (5) |
Mb, body mass; Tlc, lower critical limit of thermoneutrality; Tb, body temperature; Cmin, minimum wet thermal conductance; BMR, basal metabolic rate.
Values are means ± 95% CI; sample sizes in parentheses. Initial values are those of unacclimated birds held in outdoor aviaries; Acclimation I values were measured following a 21-day acclimation period; acclimation II values were measured following a further 21-day acclimation period.
Acclimation II data are presented in two ways: for each of the six combinations of acclimation air temperature (Tacc) I and II, and pooled according to TaccII. Note that whereas the initial and acclimation I values for each Tacc were measured in the same individuals, values for acclimation II were not.
Values from 15 additional birds not used in main experiment.