| Abbreviation | Definition |
|---|---|
| MASH | Metropolitan Animal Specialty Hospital |
| MAWO | Meru Animal Welfare Organization |
| MBAH | Mississippi Board of Animal Health |
| MBK | Mexican Black Kingsnake |
| MBNG | Mycotic Bovine Nasal Granuloma |
| MCAL | Monroe County Animal League |
| MCAR | Mitchell County Animal Rescue |
| MCAS | Montgomery County Animal Shelter |
| MCAS | Multnomah County Animal Services |
| MCCA | Massas Creek Companion Animals |
| MCFA | Monroe County Friends of Animals |
| MCFB | Medical Center For Birds |
| MEAT | Mormons for Ethical Animal Treatment |
| MECA | Milwaukee Emergency Center For Animals |
| MFA | Mercy For Animals |
| MFH | Master of Fox Hounds |
| MFH | Molly Fish Hobbiest |
| MHAA | Mid Hudson Animal Aid |
| MIAR | Malaysia Independent Animal Rescue |
| MID | Mildly Intrigued Dogs |