Acclimatization and response of minipigs toward humans

As a first step toward making an efficient acclimatization methodology for minipigs, the reaction of Gottingen minipigs, 3-24 months of age, toward hu mans was investigated. All minipigs were kept in an individual cage, and th e reaction toward humans (acclimatization index) was evaluated by simple ob servations. The acclimatization index was evaluated as the total number of points scored (0-30 points) based on the following criteria: (1) the positi on of the minipig when the cage door was opened; (2) the reaction of the mi nipig when the observer approached; and (3) the reaction of the minipig whe n the observer touched it. Subsequently, each animal was ranked by total po ints scored: 30 points = AA, 20 points less than or equal to A < 30 points, 10 points less than or equal to B < 20 points, 0 points less than or equal to C < 10 points. Based on this evaluation, the reactions of minipigs unde r three conditions were investigated. The following findings were confirmed : first, minipig reaction to humans was influenced by monthly age; second, taming was possible under ordinary conditions of care, but we had to wait u ntil 10 months of age on average for this to occur; third, if simple contac t was made during care time, minipigs became tame within less than 4 weeks after the commencement of contact. We therefore consider it possible to art ificially control the reaction of minipigs toward humans, and to make minip igs more available for experiments by adding control of the hereditary fact ors that influence this reaction.