Table 2.
Quantitative Morphometric Analysis
| Strain (n) | Encl. Rad. (mm) | N | MEA (mm2) | N/MEA | CV% (N/MEA) | k |
|---|---|---|---|---|---|---|
| PND25 | ||||||
| Crl:LE (14) | 7.06 ± 0.26 | 1586 ± 130 | 52.9 ± 3.6 | 29.8 ± 0.9 | 11.3 | 0.667 ± 0.020 |
| Crl:SD (16) | 7.18 ± 0.35 | 2067 ± 140 | 64.3 ± 4.3 | 32.3 ± 0.7 | 9.2 | 0.582 ± 0.025 |
| Hsd:SD (15) | 8.75 ± 0.36c | 2545 ± 137ab | 76.1 ± 4.0c | 33.6 ± 1.0d | 10.9 | 0.554 ± 0.019ac |
| PND33 | ||||||
| Crl:LE (21) | 11.7 ± 0.3 | 3834 ± 150 | 136.0 ± 6.18 | 28.5 ± 0.5 | 8.6 | 0.389 ± 0.012 |
| Crl:SD (15) | 11.5 ± 0.4 | 4365 ± 247 | 146.6 ± 8.60 | 29.9 ± 0.6 | 7.4 | 0.383 ± 0.017 |
| Hsd:SD (8) | 12.7 ± 0.5 | 4888 ± 266c | 161.5 ± 10.8 | 30.5 ± 1.0 | 9.1 | 0.356 ± 0.016 |
Encl. Rad. = Enclosing Radius measured as the distance from point of attachment to most distal point of the epithelial tree; N = total intersections; MEA = MG Area determined by outline of the shortest distance around the entire gland; CV% (N/MEA) = coefficient of variation; k = regression coefficient, smaller values of k are indicative of fuller distal epithelial branching.
a
p < 0.05 from Crl:SD;
b
p < 0.0001 from Crl:LE;
c
p < 0.01 from Crl:LE;
d
p < 0.05 from Crl:LE by ANOVA with Tukey multiple comparison post-hoc test. Values reported are means ± SEM. PND45 was not evaluated due to limitations of the analysis.