Laboratory animals often have to endure a wide variety of environmental stressors, which in turn stresses out the animal and negatively affects animal psychology. Unfortunately, many major sources of stress involve experimental procedures which often include painful or fear-evoking events. But, training use positive reinforcement to have the animals participate in voluntary experimental procedures such as clinical examinations, will reduce the stress levels of the animal.
Laboratory pigs are often used in experimental studies because they present important anatomical homologies that align with humans. Pigs are very emotionally complex and many laboratory facilities use habituation techniques to train the pigs. Ten pigs were tested. The CT group of pigs were trained to follow a stick that had a piece of apple as the primary reinforcer and a clicker was used as the conditioned reinforcer. The conditioning was observed by watching the pig's reaction to when the clicker was used behind the pig. The behavior using the stick was well observed because a curious pig will explore the target when presented by the trainer. The pigs were more hesitant when trained to touch the target using shaping.
Overall, this study allowed the pig and human to create a bond. The pigs were never stressed out during the test, and they were very happy around humans.
Jønholt, L., Bundgaard, C. J., Carlsen, M., & Sørensen, D. B. (2021, May 29). A case study on the behavioural effect of positive reinforcement training in a novel task participation test in Göttingen Mini Pigs. Animals : an open access journal from MDPI. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8229723/