An appeasing pheromone ameliorates fear responses in the brown rat (Rattus norvegicus)
Yasushi Kiyokawa,
Shigeyuki Tamogami,
Masato Ootaki,
Evelyn Kahl,
Dana Mayer,
Markus Fendt,
Satoru Nagaoka,
Tsutomu Tanikawa,
Yukari Takeuchi
Affiliations
Yasushi Kiyokawa
Laboratory of Veterinary Ethology, the University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan; Corresponding author
Shigeyuki Tamogami
Laboratory of Veterinary Ethology, the University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
Masato Ootaki
Laboratory of Veterinary Ethology, the University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
Evelyn Kahl
Institute for Pharmacology and Toxicology & Center for Behavioral Brain Sciences, Otto-von-Guericke University Magdeburg, D-39120 Magdeburg, Germany
Dana Mayer
Institute for Pharmacology and Toxicology & Center for Behavioral Brain Sciences, Otto-von-Guericke University Magdeburg, D-39120 Magdeburg, Germany
Markus Fendt
Institute for Pharmacology and Toxicology & Center for Behavioral Brain Sciences, Otto-von-Guericke University Magdeburg, D-39120 Magdeburg, Germany
Satoru Nagaoka
Daimaru Compound Chemical Co., Ltd, Nagano 381-1222, Japan
Tsutomu Tanikawa
Technical Research Laboratory, Ikari Shodoku Co., Ltd, Chiba 275-0024, Japan
Yukari Takeuchi
Laboratory of Veterinary Ethology, the University of Tokyo, Bunkyo-ku, Tokyo 113-8657, Japan
Summary: The brown rat (Rattus norvegicus) is one of the major animals both in the laboratory and in urban centers. Brown rats communicate various types of information using pheromones, the chemicals that mediate intra-species communication in minute amounts. Therefore, analyses of pheromones would further our understanding of the mode of life of rats. We show that a minute amount of 2-methylbutyric acid (2-MB) released from the neck region can ameliorate fear responses both in laboratory rats and in wild brown rats. Based on these findings, we conclude that 2-MB is an appeasing pheromone in the brown rat. A better understanding of rats themselves would allow us to perform more effective ecologically based research on social skills and pest management campaigns with low animal welfare impacts, which might contribute to furthering the advancement of science and improving public health.
