Enhancing Gerbil Welfare Through Positive Reinforcement Training in Research Environments.

Improving laboratory animal welfare by minimizing stress and promoting species-appropriate handling is a central goal of contemporary biomedical research worldwide. Clicker training, a widely recognized form of positive reinforcement training, uses a click sound as a conditioned reinforcer to bridge the desired behavior and the reward, enabling animals to learn more quickly and with reduced stress. Our research group has previously demonstrated that clicker training functions as a form of cognitive enrichment in mice and rats. In the present study, we successfully adapted this training approach for Mongolian gerbils (Meriones unguiculatus), tailoring the protocol to the species-specific behavioral characteristics of gerbils. A cohort of 43 inbred gerbils (27 females and 16 males) underwent a standardized 10-day clicker training protocol, during which they learned to voluntarily approach and interact with the experimenter's hand in exchange for a food reward. Following the training period, animals were subjected to behavioral assessments, including an Open Field Test and a standardized human interaction test, to evaluate the effects of training on exploratory behavior and human-animal interaction. Our findings demonstrate that the implementation of clicker training in gerbils is fast, efficient, and well-tolerated. Trained animals, particularly females, showed increased voluntary interaction with the experimenter's hand and reduced anxiety-like behaviors. These results suggest that species-adapted clicker training protocols can facilitate the development of trust between experimenter and animal, ultimately decreasing stress and improving both animal welfare and the reliability of experimental outcomes.