1. Sample Collection and Handling2. Diagnostic Equipment and Materials3. Diagnostic Procedures4. Molecular Diagnostics5. Streptococci and Related Genera6. Staphylococci7. Gram-negative Bacteria8. Mycoplasmas9. Miscellaneous Organisms10. Somatic Cell Count11. Bulk Tank Cultures12. On-farm Culture13. Appendix 1. General Isolation Media14. Appendix 2. Mycoplasma Medium and Testing Procedures15. Appendix 3. Other Media16. Appendix 4. Testing Procedures17. Appendix 5. Stains