Some Aspects of the Metabolic Pattern of Growth

Cumming, Mary C (1958) Some Aspects of the Metabolic Pattern of Growth. MD thesis, University of Glasgow.

Abstract

1. Total metabolism of growing male rats was measured successively for 24 hours for five-day periods from the age of 30 to 115 days at intervals of ten days (i.e. 9 periods each of five days). Three such series are described with tabular and graphical data on the components of energy, water and nitrogen exchange. 2. Total energy expenditure of male rats from 30 to 115 days varied linearly with body weight and absorbed intake of energy. Analysis of co-variance of the data indicated that the increase in energy expenditure during growth was wholly attributable to changes in body weight and food intake. 3. The diurnal pattern of oxygen consumption was estimated. 4. Energy and nitrogen balances were variable but uniformly positive. 5. Water balance over the five-day periods did not differ markedly from zero, but because of the increase in body weight during this time a relative dehydration occurred. This did not affect the relationship between energy expenditure, body weight and food intake. 6. Carcases of rats from birth to maturity were analysed for water, nitrogen, fat and heat of combustion. 7. Both from carcase analysis and from metabolic studies the nitrogen retained per dry body weight increment decreased with age, while fat and non-protein calories increased. 8. The difference in the composition of body weight gained during growth is emphasised. 9. The significance of metabolic changes during growth and the pattern of weight gain at different ages is discussed.

• Item Type: Thesis (MD)
• Qualification Level: Doctoral
• Keywords: Medicine, Physiology
• Date of Award: 1958
• Depositing User: Enlighten Team
• Unique ID: glathesis:1958-79272
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 05 Mar 2020 11:09
• Last Modified: 05 Mar 2020 11:09
• URI: https://theses.gla.ac.uk/id/eprint/79272