| Abbreviation | Definition |
|---|---|
| RIP | Riddled In Parasites |
| RIVER | Regional Institute for Veterinary Emergencies and Referrals |
| RIVMA | Rhode Island Veterinary Medical Association |
| RIVS | Research Institute for Veterinary Science |
| RJA | Regurgitant Jet Area |
| RKI | Robert Koch Institute for Infectious and Non Communicable Diseases. |
| RMCA | Rat and Mouse Club of America |
| RN | Rattus Norvegicus |
| ROAVS | Research Opinions in Animal and Veterinary Sciences |
| ROAVS | Research Opinions in Animal Veterinary Sciences |
| ROM'S | Reactive Oxygen Metabolites |
| RPA | Rural Payments Agency (formerly Intervention Board for Agricultural Produce) |
| RPCC | Rabbit Population Control Centre |
| RPSGB | Royal Pharmaceutical Society of Great Britain |
| RR | Rectal Ring |
| RRI | Rowett Research Institute |
| RRV | Ross River Virus |
| RSIN | Rural Stress Information Network |
| RSLP | Research Libraries Support Program |
| RSM | Royal Society of Medicine |