Applicability of some of the assumptions used to estimate the weight of the skeleton in the growing pig and beagle
Sheng, H.P.; Setiabudi, M.; Naiborhu, A.; Higgins, R.A.
Growth 41(4): 297-303
1977
ISSN/ISBN: 0017-4793 PMID: 604185 Document Number: 113906
Assumptions used in indirectly estimating skeletal weight were tested on 55 pigs from birth to 12 wk of age and 42 beagles from birth to 1 yr. One of the assumptions was that skeletal weight constitutes a constant proportion of lean body mass (fat-free wet weight). In the beagle, the skeletal weight was not constant, but was a decreasing proportion of lean body mass during growth. In the pig, there were no significant changes similar to those in the beagle, probably because only a small part of the growth period was studied. Also, the assumption that bone mineral was 65% of fat-free dry weight of the skeleton was not applicable to the beagle, where it increased from 55% (birth to 12 wk) to 70% (4 mth to 1 yr). In both species, skeletal growth was a function of total fat-free dry weight in tissue, but in the beagle, the ratio potassium/fat-free dry weight in tissue increased from 130 (birth to 12 wk) to 160 (4th mth to 1 yr), and reflected changes in the contribution of body cell mass and skeleton to fat-free dry weight. Assumptions used in indirectly estimating skeletal weight were tested on 55 pigs up to 12 weeks old and 42 beagles to 1 year old. One of the assumptions was that skeletal weight constitutes a constant proportion of lean body mass (fat-free wet weight). In the beagle the skeletal weight was not constant, but a decreasing proportion of lean body mass during growth. In the pig there was no significant change comparable to those in the beagle, probably because only a small part of the growth period was studied. Also, the assumption that bone mineral was 65% of fat-free dry weight of the skeleton was not applicable to the beagle, where it increased from 55% (from birth to week 12) to 70% (from month 4 to 1 year). In both species, skeletal growth was a function of total fat-free dry weight (FFDWt), but in the beagle the ratio Kt/FFDWt increased from 130 (from birth to week 12) to 160 (from month 4 to 1 year) and reflected changes in the contribution of body cell mass and skeleton to FFDWt.