title: Chronic Co-species Housing Mice and Rats Increased the Competitiveness of Male Mice.
abstract: Rats are predators of mice in nature. Nevertheless, it is a common practice to house mice and rats in a same room in some laboratories. In this study, we investigated the behavioral and physiological responsively of mice in long-term co-species housing conditions. Twenty-four male mice were randomly assigned to their original raising room (control) or a rat room (co-species-housed) for more than 6 weeks. In the open-field and light-dark box tests, the behaviors of the co-species-housed mice and controls were not different. In a 2-choice test of paired urine odors [rabbit urine (as a novel odor) vs. rat urine, cat urine (as a natural predator-scent) vs. rabbit urine, and cat urine vs. rat urine], the co-species-housed mice were more ready to investigate the rat urine odor compared with the controls and may have adapted to it. In an encounter test, the rat-room-exposed mice exhibited increased aggression levels, and their urines were more attractive to females. Correspondingly, the levels of major urinary proteins were increased in the co-species-housed mouse urine, along with some volatile pheromones. The serum testosterone levels were also enhanced in the co-species-housed mice, whereas the corticosterone levels were not different. The norepinephrine, dopamine, and 5-HT levels in the right hippocampus and striatum were not different between the 2. Our findings indicate that chronic co-species housing results in adaptation in male mice; furthermore, it appears that long-term rat-odor stimuli enhance the competitiveness of mice, which suggests that appropriate predator-odor stimuli may be important to the fitness of prey animals.
authors.affiliation: School of Life Science and Technology, Nanyang Normal University, 1638 Wolong Road, Wolong District, Nanyang 473061, Henan Province, China and.|State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101, China.
authors.forename: Ying-Juan
authors.initials: YJ
authors.lastname: Liu
authors.affiliation: School of Life Science and Technology, Nanyang Normal University, 1638 Wolong Road, Wolong District, Nanyang 473061, Henan Province, China and.
authors.forename: Lai-Fu
authors.initials: LF
authors.lastname: Li
authors.affiliation: State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101, China.
authors.forename: Yao-Hua
authors.initials: YH
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101, China.
authors.forename: Hui-Fen
authors.initials: HF
authors.lastname: Guo
authors.affiliation: School of Life Science and Technology, Nanyang Normal University, 1638 Wolong Road, Wolong District, Nanyang 473061, Henan Province, China and.
authors.forename: Min
authors.initials: M
authors.lastname: Xia
authors.affiliation: School of Life Science and Technology, Nanyang Normal University, 1638 Wolong Road, Wolong District, Nanyang 473061, Henan Province, China and.
authors.forename: Meng-Wei
authors.initials: MW
authors.lastname: Zhang
authors.affiliation: School of Life Science and Technology, Nanyang Normal University, 1638 Wolong Road, Wolong District, Nanyang 473061, Henan Province, China and.
authors.forename: Xiao-Yuan
authors.initials: XY
authors.lastname: Jing
authors.affiliation: State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101, China.
authors.forename: Jing-Hua
authors.initials: JH
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Integrated Management of Pest Insects and Rodents in Agriculture, Institute of Zoology, Chinese Academy of Sciences, 1 Beichen West Road, Chaoyang District, Beijing 100101, China.
authors.forename: Jian-Xu
authors.initials: JX
authors.lastname: Zhang
mesh_terms: D000818:Animals; D002415:Cats; D003163:Competitive Behavior; D003345:Corticosterone / Q000378:metabolism; D005260:Female; D006799:Housing, Animal; D008297:Male; D051379:Mice; D008813:Mice, Inbred ICR; D009812:Odorants / Q000032:analysis; D010675:Pheromones / Q000652:urine; D011817:Rabbits; D051381:Rats; D017207:Rats, Sprague-Dawley; D012903:Smell; D014556:Urine / Q000737:chemistry
chemical_list: D010675:Pheromones; D003345:Corticosterone
keywords: MUPs; co-species housing; hormone; mice; pheromone; rat