Dissertation
An omics approach for understanding flesh coloration in the Atlantic salmon, Salmo salar
University of the Sunshine Coast, Queensland
Doctor of Philosophy, University of the Sunshine Coast, Queensland
2021
DOI:
https://doi.org/10.25907/00099
Abstract
The characteristic pink-red flesh color of Atlantic salmon (Salmo salar) and other salmonids, referred to as pigmentation, is considered a primary and likely the highest priority standard of quality and freshness. The salmonids' flesh color results from the accumulation of carotenoids (primarily astaxanthin) that salmonids obtain from their feed. In the pathway of astaxanthin metabolism, the muscle seems to be the astaxanthin leading storage site in the salmonid body, and the liver has a vital role in catabolizing astaxanthin metabolites that are excreted into the intestinal system and reabsorbed. Following that, the gastrointestinal system is the central place where astaxanthin is taken from the food matrix, and metabolic astaxanthin or remnant astaxanthin are reabsorbed. In the salmon gastrointestinal system, pyloric caeca prove to be a significant absorptive site, while hindgut is considered critical in carotenoids reabsorption. However, it has been recorded that carotenoids utilization for flesh pigmentation is still low (less than 22% of the supplied carotenoids get incorporated). At the same time, the carotenoids in formulated feeds account for 15-25% of total feed cost or around 6-10% of the total production cost. Besides flesh color, the firm flesh texture is particularly decisive in flesh quality and customers’ product acceptance. Flesh texture results from multiple ante- and post-mortem factors, for example, feed and growth rate, connective tissue, muscle fiber protein composition network, slaughter techniques and storage conditions. In Tasmania, prolonged elevated water temperature (over 20oC) during extremely hot summers exceeded the optimal temperature range of 12oC and 18oC of Atlantic salmon, resulting in starvation and flesh color depletion at different levels of severity. Therefore, this thesis aims to understand the effect of elevated temperature on flesh color depletion and firmness across multiple tissues. A better knowledge of flesh color depletion by Atlantic salmon during extremely hot summer is vital to support the salmon farming industry in coping with drawbacks from sup-optimal environmental conditions on salmon product quality.
Details
- Title
- An omics approach for understanding flesh coloration in the Atlantic salmon, Salmo salar
- Authors
- Thu Vo
- Contributors
- Abigail Elizur (Supervisor) - University of the Sunshine Coast, Queensland, GeneCology Research Centre - Legacy
- Awarding institution
- University of the Sunshine Coast, Queensland
- Degree awarded
- Doctor of Philosophy
- Publisher
- University of the Sunshine Coast, Queensland
- DOI
- 10.25907/00099
- Organisation Unit
- University of the Sunshine Coast, Queensland; School of Science, Technology and Engineering; Centre for Bioinnovation
- Language
- English
- Record Identifier
- 99584608902621
- Output Type
- Dissertation
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