@article{fdi:010064796,
title = {{M}ethods of lipid-normalization for multi-tissue stable isotope analyses in tropical tuna},
author = {{S}ardenne, {F}any and {M}{\'e}nard, {F}r{\'e}d{\'e}ric and {D}egroote, {M}. and {F}ouche, {E}dwin and {G}uillou, {G}. and {L}ebreton, {B}. and {H}ollanda, {S}. {J}. and {B}odin, {N}athalie},
language = {{ENG}},
abstract = {{RATIONALE}: {T}he bias associated with lipid contents in fish tissues is a recalcitrant topic for trophic studies using stable isotopes. {L}ipids are depleted in the heavy carbon isotope ({C}-13) and the lipid content varies considerably among species, tissues and in both time and space. {W}e have applied and assessed different correction methods for tropical tuna tissues. {METHODS}: {W}e tested two types of normalization methods to deal with variable lipid content in liver, gonads, and white and red muscles of yellowfin, bigeye and skipjack tuna: a chemical extraction using dichloromethane and a mathematical correction based on three modeling approaches (linear, non-linear and mass balance models). {W}e measured isotopic ratios of bulk and lipid-free tissues and assessed the predictive ability of the correction models with the lipid-free measurements. {T}he parameters of the models were estimated from our dataset and from results from published studies on other species. {RESULTS}: {C}omparison between bulk, lipid-free and lipid-corrected isotopic ratios demonstrated that (1) chemical extraction using dichloromethane did not affect delta {N}-15 values; (2) the change in delta {C}-13 values after extraction was tissue-specific; (3) lipid-normalization models using published parameter estimates failed to predict lipid-corrected delta {C}-13 values; and (4) linear and non-linear models using parameters estimated for each tissue from our dataset provided accurate delta {C}-13 predictions for all tissues, and mass balance model for white muscle only. {CONCLUSIONS}: {M}odels using published estimates for parameters from other species cannot be used. {B}ased on a range of lipid content that do not exceed 45%, we recommend the linear model to correct the bulk delta {C}-13 values in the investigated tissues but the parameters have to be estimated from a proportion of the original data for which chemical extraction is required and the isotopic values of bulk and lipid-free tissues are measured.},
keywords = {{OCEAN} {INDIEN}},
journal = {{R}apid {C}ommunications in {M}ass {S}pectrometry},
volume = {29},
numero = {13},
pages = {1253--1267},
ISSN = {0951-4198},
year = {2015},
DOI = {10.1002/rcm.7215},
URL = {http://www.documentation.ird.fr/hor/fdi:010064796},
}