Many theories have emerged to explain how ageing and longevity are mediated. Two theories are the ‘Rate of Living’ (ROL) theory (the live fast, die young concept) and the uncoupling to survive hypothesis. The ROL theory postulates a positive link between energy expenditure and longevity whereas the uncoupling hypothesis predicts a negative association. For a given mass, birds tend to live longer than mammals despite having higher energy expenditures. This study began by re-examining the relationship between body mass, energy expenditure and longevity in birds using published accounts of resting metabolic rate (RMR), daily energy expenditure (DEE) and maximum lifespan potential (MLSP). It was found that, after removing the confounding effects of body mass and phylogeny, RMR and DEE were not significantly related to MLSP. There was also a significant negative association between lifetime RMR and DEE per gram, which contradicts the suggestion that this should be body mass independent. The study then elucidated the age-related changes in energy expenditure in two long-lived companion birds, budgerigars (<i>Melopsittacus undulates</i>) and cockatiels (<i>Nymphicus hollandicus</i>). Using indirect calorimetry to determine RMR and the doubly labelled water technique to estimate DEE, it was fond that these birds did not have age-related decreases in energy expenditure. These two species, along with free-living fulmars (<i>Fulmarus glacialis</i>) do not have increased oxidative damage during ageing and no age-related changes in antioxidant protection. It was also found that dietary fatty acids have no effect on oxidative damage but possibly influence antioxidant protection in fulmars.
| Identifer | oai:union.ndltd.org:bl.uk/oai:ethos.bl.uk:499113 |
| Date | January 2009 |
| Creators | Furness, Lindsay Jayne |
| Publisher | University of Aberdeen |
| Source Sets | Ethos UK |
| Detected Language | English |
| Type | Electronic Thesis or Dissertation |
| Source | http://digitool.abdn.ac.uk:80/webclient/DeliveryManager?pid=25473 |
Page generated in 0.0021 seconds