Figure 2

Abnormalities of bull spermatozoa stained with eosin-nigrosin. Sperm with normal cell membrane structure remained unstained (live, black arrow). Sperm with a damaged cell membrane stain pink (dead, red arrow). 1. Normal; 2. Loose head; 3. Severe pyriform head; 4. Double head; 5. Teratoid; 6. Inmature form; 7. Microcephaly; 8. Distal midpiece reflex; 9. Tightly coiled tail; 10. Broken neck; 11. Dag defect; 12. Bent midpiece; 13. Broken midpiece; 14. Proximal droplet; 15. Distal droplet; 16. Nuclear vacuoles based on Perry31.