Development and validation of a cephalic conformation scoring system for the domestic rabbit (Oryctolagus cuniculus)

Extreme cephalic conformation has been theorised to be associated with compromised health in rabbits. However, recognition and assessment of such phenotypes remain largely subjective. This study aimed to develop and validate a visual, semi-quantitative system for head shape phenotype in rabbits.

Images of rabbits were collected and visually analysed for comparative phenotypic patterns, with a 1-5 grading scale subsequently created. Initial validation of the system was conducted via an online pilot survey across 24 experienced individuals. Interobserver agreement across scores was calculated to assess the reliability of the system.

The proposed system yielded strong, 'almost perfect' and statistically significant interobserver agreement for cephalic assessment (W = 0.908, 95% bias-corrected and accelerated [BCa] confidence interval [CI]: 0.858-0.950; α = 0.880, 95% CI: 0.875-0.885), with largely positive feedback from veterinary professionals.

Further development and validation of the system are required for complete, reliable assessment of all rabbits, particularly those with longer fur. Wider participation in the validation of this method from across the profession is also necessary.

This system has the potential to enhance conformational assessment in rabbits. Implementation of the system in clinical practice may help to promote awareness of potential conformation-associated health risks and catalyse discussions regarding responsible ownership. The system may also support further studies into the precise influence of conformation on disease risk.