Diet affects resting, but not basal metabolic rate of normothermic Siberian hamsters acclimated to winter.
Comp Biochem Physiol A Mol Integr Physiol
; 160(4): 516-23, 2011 Dec.
Article
em En
| MEDLINE
| ID: mdl-21889598
ABSTRACT
We examined the effect of different dietary supplements on seasonal changes in body mass (m(b)), metabolic rate (MR) and nonshivering thermogenesis (NST) capacity in normothermic Siberian hamsters housed under semi-natural conditions. Once a week standard hamster food was supplemented with either sunflower and flax seeds, rich in polyunsaturated fatty acids (FA), or mealworms, rich in saturated and monounsaturated FA. We found that neither of these dietary supplements affected the hamsters' normal winter decrease in m(b) and fat content nor their basal MR or NST capacity. NST capacity of summer-acclimated hamsters was lower than that of winter-acclimated ones. The composition of total body fat reflected the fat composition of the dietary supplements. Resting MR below the lower critical temperature of the hamsters, and their total serum cholesterol concentration were lower in hamsters fed a diet supplemented with mealworms than in hamsters fed a diet supplemented with seeds. These results indicate that in mealworm-fed hamsters energy expenditure in the cold is lower than in animals eating a seed-supplemented diet, and that the degree of FA unsaturation of diet affects energetics of heterotherms, not only during torpor, but also during normothermy.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Metabolismo Basal
/
Phodopus
/
Metabolismo Energético
Limite:
Animals
Idioma:
En
Ano de publicação:
2011
Tipo de documento:
Article