Time course and reversibility of changes in the gizzards of red knots alternately eating hard and soft food
The ability to change organ size reversibly can be advantageous to birds that perform long migrations. During winter, red knots ( Calidris canutus ) feed on shellfish and carry a muscular gizzard that weighs 10% of their body mass. Gizzard size decreases when these birds eat soft foods, e.g. while b...
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fthighwire:oai:open-archive.highwire.org:jexbio:204/12/2167 2023-05-15T15:48:26+02:00 Time course and reversibility of changes in the gizzards of red knots alternately eating hard and soft food Dekinga, Anne Dietz, Maurine W. Koolhaas, Anita Piersma, Theunis 2001-06-15 00:00:00.0 text/html http://jeb.biologists.org/cgi/content/short/204/12/2167 en eng Company of Biologists http://jeb.biologists.org/cgi/content/short/204/12/2167 Copyright (C) 2001, Company of Biologists Research Articles TEXT 2001 fthighwire 2013-05-27T04:28:35Z The ability to change organ size reversibly can be advantageous to birds that perform long migrations. During winter, red knots ( Calidris canutus ) feed on shellfish and carry a muscular gizzard that weighs 10% of their body mass. Gizzard size decreases when these birds eat soft foods, e.g. while breeding in the tundra. We studied the reversibility and time course of such changes using ultrasonography. Two groups of shellfish-adapted knots ( N =9 and N =10) were fed alternately a hard and a soft food type. Diet switches elicited rapid reversible changes. Switches from hard to soft food induced decreases to 60% of initial gizzard mass within 8.5 days, while switches to hard food induced increases in gizzard mass to 147% within 6.2 days. A third group of knots ( N =11), adapted to soft food for more than 1 year, initially had very small gizzards (25% of the mass of shellfish-adapted gizzards), but showed a similar capacity to increase gizzard size when fed shellfish. This is the first non-invasive study showing rapid digestive organ adjustments in non-domesticated birds. Text Calidris canutus Tundra HighWire Press (Stanford University) |
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HighWire Press (Stanford University) |
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English |
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Research Articles |
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Research Articles Dekinga, Anne Dietz, Maurine W. Koolhaas, Anita Piersma, Theunis Time course and reversibility of changes in the gizzards of red knots alternately eating hard and soft food |
topic_facet |
Research Articles |
description |
The ability to change organ size reversibly can be advantageous to birds that perform long migrations. During winter, red knots ( Calidris canutus ) feed on shellfish and carry a muscular gizzard that weighs 10% of their body mass. Gizzard size decreases when these birds eat soft foods, e.g. while breeding in the tundra. We studied the reversibility and time course of such changes using ultrasonography. Two groups of shellfish-adapted knots ( N =9 and N =10) were fed alternately a hard and a soft food type. Diet switches elicited rapid reversible changes. Switches from hard to soft food induced decreases to 60% of initial gizzard mass within 8.5 days, while switches to hard food induced increases in gizzard mass to 147% within 6.2 days. A third group of knots ( N =11), adapted to soft food for more than 1 year, initially had very small gizzards (25% of the mass of shellfish-adapted gizzards), but showed a similar capacity to increase gizzard size when fed shellfish. This is the first non-invasive study showing rapid digestive organ adjustments in non-domesticated birds. |
format |
Text |
author |
Dekinga, Anne Dietz, Maurine W. Koolhaas, Anita Piersma, Theunis |
author_facet |
Dekinga, Anne Dietz, Maurine W. Koolhaas, Anita Piersma, Theunis |
author_sort |
Dekinga, Anne |
title |
Time course and reversibility of changes in the gizzards of red knots alternately eating hard and soft food |
title_short |
Time course and reversibility of changes in the gizzards of red knots alternately eating hard and soft food |
title_full |
Time course and reversibility of changes in the gizzards of red knots alternately eating hard and soft food |
title_fullStr |
Time course and reversibility of changes in the gizzards of red knots alternately eating hard and soft food |
title_full_unstemmed |
Time course and reversibility of changes in the gizzards of red knots alternately eating hard and soft food |
title_sort |
time course and reversibility of changes in the gizzards of red knots alternately eating hard and soft food |
publisher |
Company of Biologists |
publishDate |
2001 |
url |
http://jeb.biologists.org/cgi/content/short/204/12/2167 |
genre |
Calidris canutus Tundra |
genre_facet |
Calidris canutus Tundra |
op_relation |
http://jeb.biologists.org/cgi/content/short/204/12/2167 |
op_rights |
Copyright (C) 2001, Company of Biologists |
_version_ |
1766383407630123008 |