| Abbreviation | Definition |
|---|---|
| NRA | Nutrias Raccoons Alligators |
| NSAB | Nova Scotia Animal Breeders |
| NSAP | Nigerian Society for Animal Production |
| NSHA | Nantucket Safe Harbor for Animals |
| NUES | National Uniform Eartagging System |
| NYCA | New Yorkers for Companion Animals |
| O | In veterinary animal medical records O' , refers to owner of animal Ex: " O' checked dogs feet |
| OAA | Oklahoma Alliance for Animals |
| OAA | Oklahoma Animal Alliance |
| OAA | Other Aquatic Animals |
| OACA | Oklahoma Animal Control Association |
| OACC | Office of Animal Care Compliance |
| OACC | Ortega Animal Care Center |
| OACF | Oklahoma Animal Care Foundation |
| OACM | Office of Animal Care Management |
| OAHN | Ontario Animal Health Network |
| OAS | Oakland Animal Services |
| OAW | Office Of Animal Welfare |
| OBRC | Ontario Bird Records Committee |
| OCAP | Ontonagon County Animal Protection |