Skip to main content

Postprandial metabolic increment of southern bluefin tuna Thunnus maccoyii ingesting high or low-lipid sardines Sardinops sagax

Buy Article:

$51.00 plus tax (Refund Policy)


This study examined the postprandial metabolism and swimming speed of southern bluefin tuna Thunnus maccoyii when fed sardines Sardinops sagax of either high-lipid and high-energy content or low-lipid and low-energy content. Five groups of two or three T. maccoyii (mean ±s.e.mass = 19·8 ± 0·5 kg, n = 14) were fed either low [2·2% lipid, 5·5 MJ kg−1 gross energy (GE)] or high-lipid (12·9%, 9·2 MJ kg−1 GE) S. sagax. Before feeding, T. maccoyii swam at 0·74 ± 0·03 body lengths s−1 (n = 5) and their routine metabolic rate was 305 ± 15 mg kg−1 h−1. Swimming speed and metabolic rate of T. maccoyii increased following feeding. Thunnus maccoyii swam 1·3 and 1·8 times faster during digestion of low and high-lipid S. sagax, respectively. Postprandial peak metabolic rate, duration of elevated metabolism and total postprandial metabolic increment were all greater for T. maccoyii that ingested high-lipid S. sagax. When total postprandial increment is represented as a proportion of ingested energy, there was no difference between high and low-lipid meals, equating to between 30 and 35% of ingested energy. It was estimated that increased postprandial swimming costs account for 25 and 46% of the total postprandial metabolic response for low and high-lipid S. sagax meals, respectively. Specific dynamic action (SDA) accounts for c. 20% of ingested energy regardless of S. sagax lipid level. These results confirm that the postprandial metabolic increment of T. maccoyii is greater than most other fish species. Much of the high cost of postprandial metabolic increment can be attributed to increased postprandial swimming costs. For T. maccoyii, it appears that activity and SDA are not independent, which complicates bioenergetic evaluation. High postprandial metabolic costs accentuate the great energetic requirements of T. maccoyii.

Keywords: bioenergetics; dietary composition; heat increment of feeding; respiratory metabolism; specific dynamic action; swimming speed

Document Type: Regular Paper


Affiliations: School of Earth and Environmental Sciences, University of Adelaide, Adelaide 5005, Australia

Publication date: November 1, 2009

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
Cookie Policy
Ingenta Connect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more