Table 2.

Relative β (%) Regression Coefficients^a for Major Chemical Components for Four Male^b and Four Female Animals

Component	Male animals (%)
	Rat 1	Rat 2	Rat 3	Rat 4
Water	35 ± 4	39 ± 3	41 ± 3	48 ± 6
Collagen type I	48 ± 3	48 ± 4	45 ± 3	39 ± 3
Fat	10 ± 2	4 ± 2	4 ± 2	2 ± 3
Keratin	8 ± 2	9 ± 1	10 ± 2	11 ± 2

Component	Female animals (%)
	Rat 1	Rat 2	Rat 3	Rat 4
Water	47 ± 3	42 ± 4	46 ± 4	43 ± 3
Collagen type I	39 ± 3	42 ± 4	37 ± 3	41 ± 2
Fat	3 ± 1	5 ± 2	6 ± 3	5 ± 3
Keratin	9 ± 1	9 ± 1	8 ± 2	9 ± 2

^aMean value (±SD) with 396 degrees of freedom for each value.

^bData for the male rats 1 and 2 are the same as those reported before.¹⁰