title: Group housing and nest building only slightly ameliorate the cold stress of typical housing in female C57BL/6J mice.
abstract: Huddling and nest building are two methods of behavioral thermoregulation used by mice under cold stress. In the laboratory, mice are typically housed at an ambient temperature (Ta) of 20°C, well below the lower end of their thermoneutral zone. We tested the hypothesis that the thermoregulatory benefits of huddling and nest building at a Ta of 20°C would ameliorate this cold stress compared with being singly housed at 20°C as assessed by heart rate (HR), blood pressure (BP), triiodothyronine (T3), brown adipose (BAT) expression of Elovl3 mRNA, and BAT lipid content. A series of experiments using C57BL/6J female mice exposed to 20°C in the presence or absence of nesting material and/or cage mates was used to test this hypothesis. Mice showed large differences in HR, BP, shivering, and core body temperature (Tb) when comparing singly housed mice at 20°C and 30°C, but only a modest reduction in HR with the inclusion of cage mates or bedding. However, group housing and/or nesting at 20°C decreased T3 levels compared with singly housed mice at 20°C. Singly housed mice at 20°C had a 22-fold higher level of BAT Elovl3 mRNA expression and a significantly lower triacylglycerol (TAG) content of BAT compared with singly housed mice at 30°C. Group housing at 20°C led to blunted changes in both Elovl3 mRNA and TAG levels. These findings suggest that huddling and nest building have a limited effect to ameliorate the cold stress associated with housing at 20°C.
authors: Department of Biology, Williams College, Williamstown, Massachusetts.
authors: Rebecca L
authors: RL
authors: Maher
authors: Department of Biology, Williams College, Williamstown, Massachusetts.
authors: Shayna M
authors: SM
authors: Barbash
authors: Department of Biology, Williams College, Williamstown, Massachusetts.
authors: Daniel V
authors: DV
authors: Lynch
authors: Department of Biology, Williams College, Williamstown, Massachusetts sswoap@williams.edu.
authors: Steven J
authors: SJ
authors: Swoap
mesh_terms: D000123:Acetyltransferases / Q000235:genetics / Q000378:metabolism; D002001:Adipose Tissue, Brown / Q000378:metabolism; D000818:Animals; D001794:Blood Pressure; D001833:Body Temperature Regulation; D003080:Cold Temperature; D058639:Cold-Shock Response; D004780:Environment, Controlled; D000081031:Fatty Acid Elongases; D005260:Female; D006339:Heart Rate; D006799:Housing, Animal; D008810:Mice, Inbred C57BL; D009425:Nesting Behavior; D012333:RNA, Messenger / Q000378:metabolism; D012768:Shivering; D013997:Time Factors; D014280:Triglycerides / Q000378:metabolism
chemical_list: C000630960:Elovl3 protein, mouse; D012333:RNA, Messenger; D014280:Triglycerides; D000123:Acetyltransferases; D000081031:Fatty Acid Elongases
keywords: ambient temperature; blood pressure; brown fat; nesting