title: Diadem/crater defect in spermatozoa of a bull.
mesh_terms: D000177:Acrosome / Q000002:abnormalities / Q000648:ultrastructure; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000473:pathology*; D005627:Frostbite / Q000662:veterinary; D008297:Male; D008854:Microscopy, Electron; D010413:Penis / Q000293:injuries; D013094:Spermatozoa / Q000002:abnormalities* / Q000648:ultrastructure