关键词: 哺乳, 繁殖, 静止代谢率, 黑线仓鼠, 产热

Abstract: Energy budgets during peak lactation were measured in striped hamsters throughout the first,second,third and fourth lactation events. The present study showed that 1)asymptotic food intake,milk energy output (MEO),litter size and mass,resting metabolic rate (RMR),nonshivering thermogenesis (NST),mitochondria cytochrome c oxydase (COX) activity of brown adipose tissue (BAT),serum T3 ,T4 and prolactin levels did not differ between the four bouts of lactation; 2)the asymptotic food intake was significantly correlated with MEO,litter mass and RMR.This suggests that striped hamsters with different reproductive experiences are able to compensate for the high energy demands during peak lactation by increasing energy intake and decreasing energy expenditure associated with thermogenesis Sustained metabolic rate (Sus- MR)during peak lactation may be limited by the capacity to produce milk,which is more likely consistent with the prediction of the “peripheral limitation hypothesis”rather than the “central limitation hypothesis”. Limits to SusMR may be independent of the reproductive experiences.

Key words: Lactation, Reproduction, Resting metabolic rate, Striped hamster (Cricetulus barabensis), Thermogenesis