Morphological changes of platelets following platelet aggregation induced by collagen in Japanese Black cattle with...

Electron microscopic observation was performed on platelets activated by collagen stimulation in Japanese Black cattle with delta-storage pool deficiency (delta-SPD) to identify their morphological and functional abnormalities compared from normal bovine platelets. Platelets of normal Japanese Black cattle changed their shapes to spherical and were in the phase of release reactions 5 min after the collagen (90.9 microg/ml) stimulation, and most of platelets were aggregated. On the other hand, in GSPD cattle, most of a granules were still dispersed in activated platelets, although the spherical shape change of the platelets was observed. These results suggested that there are abnormalities in the release reactions in platelets of delta-SPD cattle.