| Abbreviation | Definition |
|---|---|
| ARL | Animal Refuge League |
| ARL | Animal Rescue League |
| ARM | Animal Recovery Mission |
| ARMV | Animal Rescue Merrimack Valley |
| ARNI | Animal Resource Network Incorporated |
| ARNO | Animal Rescue New Orleans |
| ARO | Animal Research |
| ARO | Animal Research Online |
| ARO | Animal Research Organization |
| ARPP | Animal Research Protection Program |
| ARRG | Animal Rights and Rescue Group |
| ARRIVE | Animal Research Reporting of In Vivo Experiments |
| ARRP | Animal Research Review Panel |
| ARRS | Animal Rights Resource Site |
| ARV | Animal Rescue Volunteers |
| ARVS | Animal Rescue Veterinary Services |
| ASAC | Animal Science Advising Center |
| ASAH | Amherst Small Animal Hospital |
| ASAP | Animal Shelter Alliance of Portland |
| ASAP | Animal Shelter Assistance Program |