Effects of nutritional manipulation on body composition in the developing marsupial, Macropus eugenii

Mol Cell Endocrinol. 2016 Jun 15:428:148-60. doi: 10.1016/j.mce.2016.03.030. Epub 2016 Mar 28.

Abstract

When 60-day-old tammar wallaby pouch young (Macropus eugenii) are fostered to mothers at 120 days of lactation, their growth, developmental rate and maturation of their GH/IGF axes are markedly accelerated. To determine the effect of fostering on energy intake, body composition and fat accretion, we first measured total body fat and lean mass in these young. Next, we mimicked the triglyceride oleic and palmitic acid composition of 120-day milk by supplementing 60 day young with these fatty acids and comparing their growth with that of growth accelerated young. There was no difference in the weight or growth axis maturation of supplemented young but there was significantly more body fat in these and in the growth-accelerated fostered young than in controls. We conclude that the accelerated growth and GH/IGF axis maturation observed previously in fostered young is most likely due to increased milk consumption and earlier access to specific nutrients.

Keywords: Adipose tissue; Fatty acids; Growth acceleration; Growth axis; Marsupial; Tammar wallaby.

MeSH terms

  • Adipocytes / cytology
  • Adipocytes / drug effects
  • Adipose Tissue / anatomy & histology
  • Adipose Tissue / drug effects
  • Animal Nutritional Physiological Phenomena* / drug effects
  • Animals
  • Body Composition* / drug effects
  • Cell Size / drug effects
  • Dietary Supplements
  • Energy Metabolism / drug effects
  • Gene Expression Regulation, Developmental / drug effects
  • Growth Hormone / blood
  • Insulin-Like Growth Factor I / genetics
  • Insulin-Like Growth Factor I / metabolism
  • Lactation / drug effects
  • Liver / drug effects
  • Liver / metabolism
  • Macropodidae / blood
  • Macropodidae / genetics
  • Macropodidae / growth & development*
  • Macropodidae / physiology*
  • Milk / metabolism
  • Oils / pharmacology
  • Organ Size / drug effects
  • Postpartum Period / blood
  • Postpartum Period / drug effects
  • RNA, Messenger / genetics
  • RNA, Messenger / metabolism

Substances

  • Oils
  • RNA, Messenger
  • emu Oil
  • Insulin-Like Growth Factor I
  • Growth Hormone