| dc.description.abstract | At birth, major differences in degree of development between precocial animals and altricial animals are evident, where precocials are relatively mature in contrast to altricials. The transition of non-load bearing to load bearing immediately after birth in precocial animals only takes a few hours, therefore the bones of precocials, such as foals, should be ready for loading before the onset of walking. If bone remodelling occurs according to Wolff’s law, it will always lag behind. We hypothesize that collagen fibres will become more organized within bone of older foals compared to bone from younger foals. We expect a difference in birefringence between different location within one bone sample, since the bone age differs. Besides these hypothesises we also expect more birefringence on the lateral part of the talus compared to the medial part of the talus, because of the anatomy of the equine hind limb and the direction of the forces on it.
In order to test the hypothesis 20 Dutch Warmblood foals, ranging in age of approximately two weeks before birth until five months after birth were available. Bone samples of these animals were stained with H&E and examined with polarized light microscopy. Where after it was examined with polarize light microscopy in order to measure the birefringence of the collagen fibres.
The birefringence increased with increasing age, aside from age category 1 and 2, within all bone samples. In the medial talus a significant increase in birefringence was found between different location, comparing older and younger bone in one bone sample. In the foals of age category 2 a significant difference was found between the birefringence of the lateral and medial talus.
In conclusion the collagen fibre alignment increases with age, however, more knowledge about the alteration, due to the distribution pattern of the forces, of collagen fibre orientation within trabeculae is necessary. | |
