Structural differences in the brain between wild and laboratory rats (Rattus norvegicus): Potential contribution to wariness

The Journal of Veterinary Medical Science

Ryoko KOIZUMI¹  Yasushi KIYOKAWA² 

[1] Laboratory of Veterinary Ethology, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan;Technical Research Laboratory, Ikari Shodoku Corporation, 1-12-3 Akanehama, Narashino-shi, Chiba 275-0024, Japan

关键词: accessory olfactory bulb;    basolateral complex of the amygdala;    bed nucleus of the stria terminalis;    main olfactory bulb;    vomeronasal receptor;   

DOI  :  10.1292/jvms.18-0052

学科分类：兽医学

来源: Japanese Society of Veterinary Science

【 摘 要 】

Wild animals typically exhibit defensive behaviors in response to a wider range and/or a weaker intensity of stimuli compared with domestic animals. However, little is known about the neural mechanisms underlying “wariness” in wild animals. Wild rats are one of the most accessible wild animals for experimental research. Laboratory rats are a domesticated form of wild rat, belonging to the same species, and are therefore considered suitable control animals for wild rats. Based on these factors, we analyzed structural differences in the brain between wild and laboratory rats to elucidate the neural mechanisms underlying wariness. We examined wild rats trapped in Tokyo, and weight-matched laboratory rats. We then prepared brain sections and compared the basolateral complex of the amygdala (BLA), the bed nucleus of the stria terminalis (BNST), the main olfactory bulb and the accessory olfactory bulb. The results revealed that wild rats exhibited larger BLA, BNST and caudal part of the accessory olfactory bulb compared with laboratory rats. These results suggest that the BLA, BNST, and vomeronasal system potentially contribute to wariness in wild rats.

【 授权许可】

Unknown