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Effects of Human Observer Presence on Pain Assessment Using Facial Expressions in Rabbits.

Renata H Pinho¹, André A Justo², Daniela S Cima³

¹Department of Surgical Specialties and Anesthesiology, Botucatu Medical School, São Paulo State University, Botucatu, São Paulo, Brazil and Faculty of Veterinary Medicine, University of Calgary, Calgary, AB, Canada.

Journal of the American Association for Laboratory Animal Science : JAALAS

|February 9, 2023

Summary

This summary is machine-generated.

A human observer significantly impacts Rabbit Grimace Scale (RbtGS) scores, potentially underestimating pain after surgery and overestimating baseline pain. This highlights the need to consider observer presence in animal welfare assessments.

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Area of Science:

Veterinary Science
Animal Welfare
Pain Assessment

Background:

The Rabbit Grimace Scale (RbtGS) is a tool for assessing pain in rabbits.
Objective pain scoring is crucial for evaluating the efficacy of analgesia and surgical outcomes.
The influence of human observation on subjective pain scoring in animals requires investigation.

Purpose of the Study:

To evaluate the effect of a human observer on Rabbit Grimace Scale (RbtGS) scores.
To determine if observer presence alters pain and analgesia assessments in rabbits post-orthopedic surgery.

Main Methods:

Video footage of 28 rabbits before and after orthopedic surgery was scored using RbtGS.
Videos were assessed at baseline, 1 hour post-surgery (pain), 3 hours post-analgesia, and 24 hours post-surgery.
Scoring was performed with and without the presence of a human observer, with evaluators blinded to conditions.

Main Results:

The RbtGS scale was responsive to pain, showing increased scores post-surgery and decreased scores by 24 hours.
Observer presence significantly reduced RbtGS scores during the presumed peak pain period (1 hour post-surgery).
Observer presence increased RbtGS scores at baseline and 24 hours post-surgery, suggesting altered pain perception.

Conclusions:

The Rabbit Grimace Scale effectively detects pain in rabbits undergoing orthopedic surgery from video footage.
The presence of a human observer can significantly bias RbtGS scores, leading to underestimation of acute pain.
Careful consideration of observer effects is necessary for accurate pain assessment and welfare monitoring in rabbits.