Refining dosing by oral gavage in the dog: A protocol to harmonise welfare

It is estimated that over 100,000 dogs are used in laboratory research and testing each year worldwide, primarily in the safety assessment of new chemical entities. We have a scientific and ethical obligation to ensure that the best quality of data is achieved from their use.

Oral gavage is a technique frequently used to deliver a compound directly into the stomach. As with other animals, in the dog, gavage is aversive and the frequency of its use is a cause for welfare concern but little research has been published on the technique nor how to Refine it (Refinement is one of the 3Rs - Replacement, Reduction, Refinement - the principles of the humane experimental technique).

We compared the effects of sham dosing (used to attempt to habituate dogs to dosing) and a Refined training protocol against a control, no-training group to determine the benefit to welfare and scientific output of each technique. Our findings show that sham dosing is ineffective as a habituation technique and ‘primes’ rather than desensitises dogs to dosing. Dogs in the control group showed few changes in parameters across the duration of the study, with some undesirable changes during dosing, while dogs in the Refined treatment group showed improvements in many parameters. It is recommended that if there is no time allocated for pre-study training a no-sham dosing protocol is used. However, brief training periods show a considerable benefit for welfare and quality of data to be obtained from the dogs' use.


Journal Article:


Caged dogs