[Changes of the femoral bone microstructure in the reindeer during the fetal period of ontogenesis].
The diaphysis of the femoral bone was studied morphometrically in 30 reindeer fetuses aged 2-7.5 months. The formation of the diaphyseal cavity of the femoral bone took place from 3 till 7.5 months, rapidly progressing during all the fetal period. The thickness of the periosteum in the epiphysis and the diaphysis of the bone increased from 2 to 6 months inclusive, whereupon it decreased by the time of birth. The cartilaginous tissue in the epiphyses was present from 2 till 7.5 months; its growth was registered up to 3 months in a proximal epiphysis, while it continued till 4 months in a distal epiphysis. Later on, the thinning of the cartilage was noted till the birth. The thickness of spongy substance of bone epiphyses increased with the fetal age. The osteons in the diaphysis of the femoral bone were formed in 2-month-old fetus, their numbers were found to increase with age. The compact substance of the diaphysis of the femoral bone increased in thickness till 5 months, whereupon the process of thinning of tissue till the time of birth, was noted.
Malkova
N M
NM
Malkov
N A
NA
D000818:Animals; D015519:Bone Density / Q000502:physiology; D018483:Diaphyses / Q000166:cytology / Q000196:embryology; D004838:Epiphyses / Q000166:cytology / Q000196:embryology; D005269:Femur / Q000166:cytology*; D005333:Fetus / Q000196:embryology; D012053:Reindeer / Q000033:anatomy & histology / Q000196:embryology*