Do Calorimetric Results in Mice Depend on the System Being Used?

• Published in: Obesity (Silver Spring, Md.) Vol. 27; no. 5; p. 689
• Main Author: Kaiyala, Karl J.
• Format: Journal Article
• Language: English
• Published: United States Blackwell Publishing Ltd 01.05.2019
• Subjects: Animals; Calorimetry; Diet, High-Fat; Energy; Food; Heat; Metabolism; Mice; Obesity
• ISSN: 1930-7381; 1930-739X
• DOI: 10.1002/oby.22498

Indirect calorimetry is routinely used to assess energy expenditure, metabolism, and energy balance in rodents, and currently multiple commercial systems are in use in the scientific community. Compared with the OxyMax system, Promethion activity counts were lower; food intake during HC feeding was lower; and the respiratory exchange ratio during HC feeding was both lower and below the diet's food quotient (FQ) (RER is carbon dioxide production [VCO2] 4 oxygen uptake [VO2]; FQ is the RER predicted by diet composition when mice are in energy balance during measurements (3)). A similar fan increased heat production by an aluminum mouse mannequin instrumented with feedback control to maintain 37°C (pp. 154-155 in (3)), and published data on the relationship between heat production and ambient temperature in mice indeed point to a substantially higher slope in OxyMax (2) vs.