The ovariectomized sheep has been proposed as a model of human osteoporosis, showing high bone turnover, increased osteoclastic activity, perforation of trabeculae and endosteal resorption. To improve scientific knowledge on this large-size osteopenic animal model, 15 crossbred sheep (4±1 years, 80±5 kg) were divided in 3 groups of 5 animals each: 1) Baseline Group, where animals were sacrificed at the beginning of the study as controls; 2) OVX Group, where animals were bilaterally ovariectomized; 3) SHAM Group, where the operation was simulated. OVX and SHAM animals were sacrificed 24 months after surgery. A histomorphometric analysis was performed on cancellous (iliac crest, and 4th and 5th lumbar vertebral bodies) and cortical (femoral and tibial middiaphyses) bone. In the OVX Group, results showed generalised and significant resorption of cancellous bone in the iliac crest and lumbar vertebrae, as well as significant resorption of cortical bone in the tibia. The cancellous bone of the vertebral bodies appeared to be more sensitive to the estrogen-deficiency than the iliac crest and the same can be said for the tibial middiaphyseal cortical bone versus the femoral one. In conclusion, our results seem to support the use of an ovariectomized sheep model for pharmacological and surgical studies on osteoporosis. However, differences in bone reaction to estrogen-deficiency at different anatomical sites should be taken into account and do require further investigations.
|Number of pages||12|
|Journal||Journal of Applied Animal Research|
|Publication status||Published - Dec 2001|
ASJC Scopus subject areas
- Animal Science and Zoology