Variations in enzyme activity of brown adipose tissue and liver during postnatal development energy requirements during lactation in Eothenomys miletus (Mammalia: Rodentia: Cricetidae)

In order to investigate the postnatal development of thermoregulatory ability in Eothenomys miletus, body mass as well as mitochondrial protein (MP) contents and cytochrome c oxidase (COX) activity of brown adipose tissue (BAT) and liver were measured at day 1, 7, 13, 19, 22, 28, 34, 43 and 41, respectively. BAT mass and COX activity (per g tissue) during postnatal development increased markedly, which accord with the typical development characteristics of altricial animals. Our data showed that postnatal changes in thermogenic properties in BAT and liver mitochondrian are consistent with their thermogenic ability in E. miletus.