Summary
The technique of trans-iliac biopsy and subsequent histomorphometrical examination
in ewes is reported. Biopsies were obtained from 18 clinically normal ewes, aged 9
to 11 years which had been given tetracycline intramuscularly twice, 11 days apart,
at a dose rate of 20 mg/kg. There were no complications associated with the administration
of the tetracycline at this dose and at this site. The core of the biopsy consisted
of cancellous bone between two cortices allowing complete histomorphometric analysis
from undecalcified sections. Two clearly distinct and separate labels were visible
under ultraviolet light with the labelling method used. Primary, surface, volume and
dynamic data were measured or calculated and are reported. Certain static and dynamic
histomorphometric variables from this study were compared to those of other workers
who used aged (but slightly younger) ewes, and there were many similarities between
the studies. A comparison was also made of absolute values of bone volume (BV/TV%),
relative osteoid volume (OV/BV%) and mineral apposition rate (MAR, mcm/day) of this
study, and those of men and pre- and postmenopausal women reported in recently published
data, as well as parameters of 14 elderly normal women measured by one of us. It was
concluded that iliac crest biopsy in the ewe is a safe effective method to quantitate
skeletal changes and our data compares favorably with other workers in this species.
Furthermore, the BV/TV%, OV/BV% and MAR; of ewes of this age resembled that of both
men and postmenopausal women at least in their 6th or 7th decade of life. Therefore
9- to 11-year-old ewes may be a useful models for studies and therapeutic trials of
both osteopenia and osteoporosis of the skeleton.
The article describes the technique of trans-iliac biopsy and subsequent histomorpho-metrical
examination in aged ewes.
Keywords
Histomorphometry - sheep - osteoporosis - aging - labels - biopsy - iliac crest