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Updated: Jul 18, 2026
05:23
Establishment and Evaluation of a Sheep Model of Full-thickness Osteochondral Defect
Published on: April 14, 2026
Seasonal changes in bone metabolism in sheep
Daniel Arens1, Ilonka Sigrist, Mauro Alini
1AO Research Institute, Clavadelerstrasse, CH-7270 Davos, Switzerland.
Veterinary Journal (London, England : 1997)
|December 5, 2006
Summary
Sheep bone metabolism shows seasonal variation, impacting bone mineral density and resorption markers. Researchers recommend accounting for these natural changes when using sheep as an animal model for osteoporosis research.
Area of Science:
- Veterinary Science
- Bone Biology
- Animal Modeling
Background:
- Osteoporosis research requires reliable animal models.
- Sheep are a suitable large animal model candidate.
- Human bone mass is known to exhibit seasonal fluctuations.
Purpose of the Study:
- To investigate natural bone metabolism in sheep.
- To define sheep as a potential animal model for osteoporosis.
- To assess the impact of seasonal changes on sheep bone health.
Main Methods:
- Analysis of bone mineral density (BMD) using peripheral quantitative computed tomography (pQCT).
- Evaluation of trabecular bone structure.
- Measurement of biochemical markers for bone formation and resorption.
- Monitoring of serum estrogen levels over 18 months.
Main Results:
- Lowest BMD observed during winter months.
- A significant 5.1% increase in BMD occurred during spring and summer (P<0.05).
- Bone resorption markers were higher in spring compared to autumn (P<0.001).
- Serum estrogen levels indicated the physiological estrus phase in autumn.
Conclusions:
- Sheep bone metabolism is significantly influenced by seasonal variations.
- Seasonal changes in BMD and bone turnover must be considered for accurate osteoporosis modeling in sheep.
- Accounting for seasonality is crucial for validating sheep as a large animal model for osteoporosis.
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