Table 2. Traits across the lifespan and their correlation with selection for home cage hyperactivity.
Mean values (±SEM) of each line (“Control” and “High-Active”) are analyzed to determine whether line differences may be attributed to selective breeding for hyperactivity. The statistical significance of line differences is expressed in standardized phenotypic units, which are compared to their 95% confidence interval; absolute values which fall outside of this interval indicate the difference is a correlated genetic response. “M”=male, “F”= female, “MF”=collapsed by sex, “HA”=High-Active, “CON”=Control; abbreviations separated by a colon indicate mice of a genetic line raised by a line (e.g., HA:CON indicates High-Active mice raised by Control dams). “P-value” refers to a standard pair-wise comparison of the High-Active versus Control (for Generation 19 weaning and adult body mass and activity levels, lines raised by Control dams are compared and emphasized in bold); a heritability (“h2”) reference was used for analyses of body mass at PNDs 21 and 60 (as the heritability estimate was calculated at PND 49 [23], we considered its application to PNDs 0 and 6 inappropriate) as well as our calculated heritability for activity (Table 1); “F” refers to the inbreeding coefficient; “n” refers to the number of families represented in the cohort; “95% CI” refers to the 95% confidence interval for Dy expected by genetic drift; “Dy” refers to the difference between lines in standardized phenotypic SD units, and those values in bold are considered correlated responses to selection.
| Gen | Trait | PND | Sex | High-Active line | Control line | P-value | h2 | F | n | 95% CI | Dy | |||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 18 | Mass | 21 | M | 10.3 (±0.5) | 14.7 (±0.6) | 0.0001 | 0.31 | 0.06 | 19 | 1.05 | −1.73 | |||
| F | 11.4 (±0.5) | 14.2 (±0.7) | 0.001 | 0.31 | 0.06 | 19 | 1.05 | −1.01 | ||||||
| 18 | Mass | 60 | M | 22.7 (±0.5) | 28.7 (±1.6) | 0.0001 | 0.31 | 0.06 | 19 | 1.05 | −1.24 | |||
| F | 19.5 (±0.5) | 23.1 (±1.0) | 0.01 | 0.31 | 0.06 | 19 | 1.05 | −1.04 | ||||||
| 18 | Activity | 60 | M | 1.72 (±0.1) | 0.33 (±0.02) | 0.0001 | 0.40 | 0.06 | 19 | 1.09 | 3.22 | |||
| F | 2.14 (±0.2) | 0.48 (±0.07) | 0.0001 | 0.40 | 0.06 | 19 | 1.09 | 2.26 | ||||||
| 19 | Mass | 0 | MF | 1.54 (±0.06) | 1.68 (±0.06) | 0.11 | - | - | - | - | - | |||
| 19 | Mass | 6 | MF | 4.38 (±0.2) | 4.88 (±0.1) | 0.04 | - | - | - | - | - | |||
| HA:HA | HA:CON | CON:CON | CON:HA | |||||||||||
| 19 | Mass | 21 | M | 14.1 (±0.3) | 14.4 (±0.3) | 15.7 (±0.3) | 14.7 (±0.5) | 0.003 | 0.31 | 0.06 | 37 | 0.84 | −0.79 | |
| F | 13.5 (±0.4) | 14.2 (±0.3) | 14.3 (±0.4) | 14.1 (±0.4) | NS | 0.31 | 0.06 | 37 | 0.84 | −0.04 | ||||
| 19 | Mass | 60 | M | 26.3 (±0.5) | 24.9 (±0.6) | 27.5 (±1.1) | 27.7 (±0.9) | 0.03 | 0.31 | 0.06 | 37 | 0.84 | −0.78 | |
| F | 20.6 (±0.6) | 21.1 (±0.6) | 20.6 (±0.8) | 21.4 (±0.9) | NS | 0.31 | 0.06 | 37 | 0.84 | −0.17 | ||||
| 19 | Activity | 60 | M | 2.38 (±0.2) | 2.9 (±0.3) | 0.85 (±0.1) | 0.68 | (±0.1) | 0.0001 | 0.40 | 0.06 | 37 | 0.89 | 1.69 |
| F | 3.33 (±0.3) | 3.0 (±0.3) | 1.08 (±0.2) | 0.78 | (±0.1) | 0.0001 | 0.40 | 0.06 | 37 | 0.89 | 1.70 | |||