Exploring first-feeding diets for European eel larval culture: Insights at morphological, nutritional, and molecular levels.
Closing the life cycle of European eel (Anguilla anguilla) in captivity is targeted to provide a sustainable, year-round supply of juveniles for aquaculture. Present focus is on the nutritional requirements during the larval first-feeding period. In this study, three experimental diets were tested o...
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ftdoajarticles:oai:doaj.org/article:c5c98ffce8e34f09a9c7d7b5767ccedb 2023-06-11T04:03:47+02:00 Exploring first-feeding diets for European eel larval culture: Insights at morphological, nutritional, and molecular levels. Elisa Benini Kasun A Bandara Sebastian Nikitas Politis Sofia Engrola Anders Nielsen Luis E C Conceição Andre Santos Sune Riis Sørensen Jonna Tomkiewicz 2023-01-01T00:00:00Z https://doi.org/10.1371/journal.pone.0283680 https://doaj.org/article/c5c98ffce8e34f09a9c7d7b5767ccedb EN eng Public Library of Science (PLoS) https://doi.org/10.1371/journal.pone.0283680 https://doaj.org/toc/1932-6203 1932-6203 doi:10.1371/journal.pone.0283680 https://doaj.org/article/c5c98ffce8e34f09a9c7d7b5767ccedb PLoS ONE, Vol 18, Iss 4, p e0283680 (2023) Medicine R Science Q article 2023 ftdoajarticles https://doi.org/10.1371/journal.pone.0283680 2023-05-07T00:35:22Z Closing the life cycle of European eel (Anguilla anguilla) in captivity is targeted to provide a sustainable, year-round supply of juveniles for aquaculture. Present focus is on the nutritional requirements during the larval first-feeding period. In this study, three experimental diets were tested on hatchery-produced European eel larvae from the onset of the first-feeding stage commencing 10 days post hatch (dph) until 28 dph. Larval mortality was recorded daily, while sampling was conducted at regular intervals to record larval biometrics and analyze the expression of genes related to digestion, appetite, feed intake and growth. Two periods of high mortality were identified: the first appeared shortly after introduction of feeds (10-12 dph), while the second occurred 20-24 dph, indicating the "point of no return". This interpretation was supported at the molecular level by the expression of the gene encoding the "hunger hormone" ghrelin (ghrl) that peaked at 22 dph in all dietary trials, suggesting that most larvae were fasting. However, in larvae fed diet 3, ghrl expression was downregulated beyond 22 dph, which indicated that those larvae were no longer starving at this stage, while upregulation of genes encoding the major digestive enzymes (try, tgl, and amyl2a) advocated their healthy development. Moreover, for larvae fed diet 3, the expression of those genes as well as genes for feed intake (pomca) and growth (gh) continued to increase towards 28 dph. These results together with the registered highest survival, largest dry weight increase, and enhanced biometrics (length and body area) pointed to diet 3 as the best-performing. As a whole, this first-feeding study represents a landmark being the first to document European eel larval growth and survival beyond the point of no return, providing novel insights into the molecular development of digestive functions during the first feeding stage. Article in Journal/Newspaper Anguilla anguilla Directory of Open Access Journals: DOAJ Articles PLOS ONE 18 4 e0283680 |
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topic |
Medicine R Science Q |
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Medicine R Science Q Elisa Benini Kasun A Bandara Sebastian Nikitas Politis Sofia Engrola Anders Nielsen Luis E C Conceição Andre Santos Sune Riis Sørensen Jonna Tomkiewicz Exploring first-feeding diets for European eel larval culture: Insights at morphological, nutritional, and molecular levels. |
topic_facet |
Medicine R Science Q |
description |
Closing the life cycle of European eel (Anguilla anguilla) in captivity is targeted to provide a sustainable, year-round supply of juveniles for aquaculture. Present focus is on the nutritional requirements during the larval first-feeding period. In this study, three experimental diets were tested on hatchery-produced European eel larvae from the onset of the first-feeding stage commencing 10 days post hatch (dph) until 28 dph. Larval mortality was recorded daily, while sampling was conducted at regular intervals to record larval biometrics and analyze the expression of genes related to digestion, appetite, feed intake and growth. Two periods of high mortality were identified: the first appeared shortly after introduction of feeds (10-12 dph), while the second occurred 20-24 dph, indicating the "point of no return". This interpretation was supported at the molecular level by the expression of the gene encoding the "hunger hormone" ghrelin (ghrl) that peaked at 22 dph in all dietary trials, suggesting that most larvae were fasting. However, in larvae fed diet 3, ghrl expression was downregulated beyond 22 dph, which indicated that those larvae were no longer starving at this stage, while upregulation of genes encoding the major digestive enzymes (try, tgl, and amyl2a) advocated their healthy development. Moreover, for larvae fed diet 3, the expression of those genes as well as genes for feed intake (pomca) and growth (gh) continued to increase towards 28 dph. These results together with the registered highest survival, largest dry weight increase, and enhanced biometrics (length and body area) pointed to diet 3 as the best-performing. As a whole, this first-feeding study represents a landmark being the first to document European eel larval growth and survival beyond the point of no return, providing novel insights into the molecular development of digestive functions during the first feeding stage. |
format |
Article in Journal/Newspaper |
author |
Elisa Benini Kasun A Bandara Sebastian Nikitas Politis Sofia Engrola Anders Nielsen Luis E C Conceição Andre Santos Sune Riis Sørensen Jonna Tomkiewicz |
author_facet |
Elisa Benini Kasun A Bandara Sebastian Nikitas Politis Sofia Engrola Anders Nielsen Luis E C Conceição Andre Santos Sune Riis Sørensen Jonna Tomkiewicz |
author_sort |
Elisa Benini |
title |
Exploring first-feeding diets for European eel larval culture: Insights at morphological, nutritional, and molecular levels. |
title_short |
Exploring first-feeding diets for European eel larval culture: Insights at morphological, nutritional, and molecular levels. |
title_full |
Exploring first-feeding diets for European eel larval culture: Insights at morphological, nutritional, and molecular levels. |
title_fullStr |
Exploring first-feeding diets for European eel larval culture: Insights at morphological, nutritional, and molecular levels. |
title_full_unstemmed |
Exploring first-feeding diets for European eel larval culture: Insights at morphological, nutritional, and molecular levels. |
title_sort |
exploring first-feeding diets for european eel larval culture: insights at morphological, nutritional, and molecular levels. |
publisher |
Public Library of Science (PLoS) |
publishDate |
2023 |
url |
https://doi.org/10.1371/journal.pone.0283680 https://doaj.org/article/c5c98ffce8e34f09a9c7d7b5767ccedb |
genre |
Anguilla anguilla |
genre_facet |
Anguilla anguilla |
op_source |
PLoS ONE, Vol 18, Iss 4, p e0283680 (2023) |
op_relation |
https://doi.org/10.1371/journal.pone.0283680 https://doaj.org/toc/1932-6203 1932-6203 doi:10.1371/journal.pone.0283680 https://doaj.org/article/c5c98ffce8e34f09a9c7d7b5767ccedb |
op_doi |
https://doi.org/10.1371/journal.pone.0283680 |
container_title |
PLOS ONE |
container_volume |
18 |
container_issue |
4 |
container_start_page |
e0283680 |
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1768383349889433600 |