Amino acid-specific δ15N trophic enrichment factors in fish fed with formulated diets varying in protein quantity and quality

Sesarmid crabs play an important role in organic matter and carbon cycling of mangrove forests. Visual observations and gut content studies have verified that sesarmid crabs are feeding on mangrove leaves, yet stable isotopes of carbon and nitrogen (13C and 15N) have indicated that leaf litter is not assimilated as a food source. Sesarmid crabs tend to be much more enriched in 13C than leaf litter (0.9‰ – 11.6‰) and have C values that are often more like microphytobenthos (MPB). General 13C trophic enrichment factors (TEF; 0.1‰ – 0.5‰) suggest crabs feed more heavily on MPB. Field and laboratory-based evidence reveal that general 13C TEF for crabs feeding on mangrove leaves may be incorrect and much greater than 0.1‰ – 0.5‰. A food web study conducted annually over 2 yrs revealed a shift in the δ13C and δ15N of Parasesarma sp. crabs similar to mangrove leaves also sampled. This suggested Parasesarma sp. may be feeding more heavily on mangrove leaves than previously reported despite crabs being 4.4‰ – 11.6‰ more enriched in 13C than mangrove leaves. A laboratory feeding study confirmed that average 13C TEF between Parasesarma sp. and decayed Rhizophora sp. leaves was 3.3‰ (SE 0.5). The Stable Isotope Analysis in R package (SIAR) used with our TEF and the general 0.5‰ 13C TEF revealed that published TEFs may underestimate mangrove leaf contributions to sesarmid crab diets on average by 33.3% (SE 0.1) and overestimate MPB and epiphytic algal contributions by 31.3% (SE 0.1). Food web studies in mangroves and other ecosystems will continue to inaccurately identify important food resources or food web structures unless more accurate and species-specific isotope fractionation values are determined.

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Amino Acid Isotope Incorporation and Enrichment Factors in Pacific Bluefin Tuna, Thunnus orientalis

PLoS ONE ◽

10.1371/journal.pone.0085818 ◽

2014 ◽

Vol 9 (1) ◽

pp. e85818 ◽

Cited By ~ 42

Author(s):

Christina J. Bradley ◽

Daniel J. Madigan ◽

Barbara A. Block ◽

Brian N. Popp

Keyword(s):

Amino Acid ◽

Bluefin Tuna ◽

Enrichment Factors ◽

Pacific Bluefin Tuna ◽

Thunnus Orientalis ◽

Isotope Incorporation

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Effect of diet on breeders and inheritance in syngnathids: application of isotopic experimentally derived data to field studies

Marine Ecology Progress Series ◽

10.3354/meps13315 ◽

2020 ◽

Vol 650 ◽

pp. 107-123 ◽

Cited By ~ 4

Author(s):

M Planas ◽

A Chamorro ◽

A Paltrinieri ◽

S Campos ◽

A Jiménez ◽

...

Keyword(s):

Fish Species ◽

Field Studies ◽

Enrichment Factors ◽

Hippocampus Guttulatus ◽

Relative Contribution ◽

Source Contributions ◽

Trophic Enrichment ◽

Isotope Mixing Models ◽

Derived Data ◽

Isotopic Effects

Syngnathids are vulnerable ovoviviparous fishes in which males undergo repeated brooding within a reproductive season. The isotopic effects of diet on both breeders (pooled sexes) and parent-egg transmission have been demonstrated in a few fish species but never in syngnathids. Quantifying isotopic changes due to diet is necessary to assess parent-newborn conversions and to estimate accurate trophic enrichment factors (TEF). We assessed the isotopic (δ13C and δ15N) effects of 3 experimental diets on TEFs in seahorse Hippocampus guttulatus breeders and isotopic inheritance. Our results suggest that H. guttulatus follows an income-capital continuum pattern for parent-egg transmission. The isotopic variability in diets for breeders and the resulting experimentally derived TEFs were compared with fixed TEFs from reviews to estimate their impact on the relative contribution of potential prey sources in syngnathids from the Cíes archipelago (Atlantic Islands National Park, NW Spain). We estimated source contributions using stable isotope mixing models (SIMMs) by combining prey sources into ecologically informative groups and incorporating informative priors. We demonstrate that (1) most frequently used TEFs from reviews might not be suitable for all fish species, particularly syngnathids, and (2) dietary source variability has a great effect on source contribution estimates. This study is also the first to provide specific TEFs for syngnathids.

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Stable carbon and nitrogen isotope trophic enrichment factors for Steller sea lion vibrissae relative to milk and fish/invertebrate diets

Marine Ecology Progress Series ◽

10.3354/meps11205 ◽

2015 ◽

Vol 523 ◽

pp. 255-266 ◽

Cited By ~ 13

Author(s):

CA Stricker ◽

AM Christ ◽

MB Wunder ◽

AC Doll ◽

SD Farley ◽

...

Keyword(s):

Nitrogen Isotope ◽

Enrichment Factors ◽

Steller Sea Lion ◽

Stable Carbon ◽

Sea Lion ◽

Carbon And Nitrogen ◽

Trophic Enrichment

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Variation in δ13C and δ15N trophic enrichment factors among Hyalella azteca amphipods from different lakes

Hydrobiologia ◽

10.1007/s10750-016-2846-z ◽

2016 ◽

Vol 781 (1) ◽

pp. 217-230 ◽

Cited By ~ 5

Author(s):

Kaven Dionne ◽

France Dufresne ◽

Christian Nozais

Keyword(s):

Hyalella Azteca ◽

Enrichment Factors ◽

Δ13c And Δ15n ◽

Trophic Enrichment

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The staining pattern of the tropomyosin sequence is displayed in a new paracrystal

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142372 ◽

1986 ◽

Vol 44 ◽

pp. 150-151

Author(s):

M.K. Lamvik ◽

L.L. Klatt

Keyword(s):

Amino Acid ◽

Amino Acid Sequence ◽

Staining Pattern ◽

Banding Patterns ◽

Mass Thickness ◽

New Form

Tropomyosin paracrystals have been used extensively as test specimens and magnification standards due to their clear periodic banding patterns. The paracrystal type discovered by Ohtsuki1 has been of particular interest as a test of unstained specimens because of alternating bands that differ by 50% in mass thickness. While producing specimens of this type, we came across a new paracrystal form. Since this new form displays aligned tropomyosin molecules without the overlaps that are characteristic of the Ohtsuki-type paracrystal, it presents a staining pattern that corresponds to the amino acid sequence of the molecule.

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Electron probe x-ray microanalysis and electron microscopy of amino acid absorption and transport by the small intestine: inhibition by chemical poisons and correlation to the elemental composition of the epithelial cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100142311 ◽

1986 ◽

Vol 44 ◽

pp. 134-135

Author(s):

A. J. Tousimis

Keyword(s):

Small Intestine ◽

Amino Acid ◽

Epithelial Cells ◽

Elemental Composition ◽

Isotope Labeling ◽

Structural Components ◽

X Ray ◽

Human Small Intestine ◽

Transport Studies

The elemental composition of amino acids is similar to that of the major structural components of the epithelial cells of the small intestine and other tissues. Therefore, their subcellular localization and concentration measurements are not possible by x-ray microanalysis. Radioactive isotope labeling: I131-tyrosine, Se75-methionine and S35-methionine have been successfully employed in numerous absorption and transport studies. The latter two have been utilized both in vitro and vivo, with similar results in the hamster and human small intestine. Non-radioactive Selenomethionine, since its absorption/transport behavior is assumed to be the same as that of Se75- methionine and S75-methionine could serve as a compound tracer for this amino acid.

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