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BIA on Fish
Can. J. Fish. Aquat. Sci. 62(2): 269.275 (2005)
Nonlethal estimation of proximate composition in fish
M. Keith Cox and Kyle J. Hartman
NRC Canada
The need to precisely measure growth is a common denominator in many fisheries studies, but growth measures other than total masses or lengths are nearly nonexistent because more precise measurements such as body composition analysis are often too difficult and time consuming. Here, we present a means of estimating body composition in fish quickly, and after validation, without the need to sacrifice the animal. Models built with brook trout (Salvelinus fontinalis) were linear with strong validation group relationships (R2 > 0.96) for composition parameters including water, protein, fat, fat-free, and dry masses. Subject responses to bioelectrical impedance analysis were minimal, with only slight bruising (p < 0.001) with no effect on swimming, color, bleeding, or feeding. The model was also tested on the water and dry masses of 10 warmwater fish species and found to have strong correlations (R2 > 0.86), suggesting that more general relationships may exist. Nonlethal estimation of body composition using bioelectrical impedance analysis will permit increased precision in bioenergetics energy flow and compositional studies as well as permit study of community energetics and condition on spatial and temporal scales not previously possible.
Development of Bioelectrical Impedance Analysis (BIA) for a rapid assessment of fish condition
Steve Pothoven, et al.
National Oceanic and Atmospheric Administration -- Great Lakes Environmental Research Laboratory
This project focuses on the further development of an innovative technique, bioelectrical impedance analysis (BIA), for the rapid, cost-effective, accurate, and non-lethal measure of proximate body composition (i.e. lipids, energy density) of fish collected in the field or laboratory. BIA instantaneously measures the resistance and reactance (capacitance) along the length of the fish, which then can be used to quantify proximate body composition. The study will focus on generating necessary calibration equations for three commercially important Great Lakes fishes, yellow perch, lake whitefish, and walleye, which differ in terms of mass-specific lipid content, energy density, and total body size. Ultimately, this study will enhance efforts to assess the condition (health) of these species in a rapid, cost-effective manner.
In 2005, we collected 41 yellow perch and 10 walleye from Lake Erie for BIA analysis. Preliminary results from 2005 indicate strong relationships between BIA resistance measures for yellow perch relative to total calories (r2 = 0.87) and water content (r2 = 0.88) (Fig 1). Given these positive findings, BIA holds great potential for Great Lakes researchers and agencies that desire the ability to rapidly and accurately quantify fish condition and health.
Aquaculture 271 (2007) 432-438
Bioimpedance assessment of body composition in cobia Rachycentron canadum (L. 1766)
M. Duncan, S.R. Craig, Angela N. Lunger, D.D. Kuhn, G. Salze, E. McLean
Virginia Tech Aquaculture Center, 1 Plantation Road, Blacksburg, VA 24061-0321, USA
Sixty juvenile cobia (Rachycentron canadum; 28.3±0.13 g wet wt) were randomly distributed into each of 12 tanks in a recirculation unit (n=5 tank-1). Fish were fed one of two diets (47:8 or 47:20 protein:lipid) at 6-8% body wt d-1 for 6 weeks. Each week, the composition of fish (n=5) from each dietary treatment was calculated by measuring the impedance (resistance and reactance) of a current (x µAAC and kHz) passed through a live animal. Electrodes were positioned at morphologically discrete points on the dorsal left hand side of the animal. After bioimpedance (BIA) assessment, the identical fish were sacrificed and their body composition determined using traditional, chemical methods. Results generated by chemical analyses were regressed against BIA data. Linear regression analysis was performed utilizing compositional analysis (protein, lipid and ash) as the observed values and BIA assessment for the predicted. Regressions for each body composition parameter produced high correlations in all relationships: resistance (in parallel) and protein (adj. R2=0.9569), resistance (in parallel) and total body water (adj. R2=0.9894), reactance (in parallel) and total body ash (adj. R2=0.8547), reactance (in series) and dry matter (adj. R2=0.9272) and reactance (in series) and fat-free mass (adj. R2=0.9916). The F value tests (Pb0.0001) revealed significant correlations between the independent and dependent variables for each body composition parameter. Correlations for each regression indicate strong linear relationships between impedance and proximate analysis variables with values of 1:1. This indicates that this BIA methodology can be utilized as an inexpensive, non-lethal, on the farm determination of proximate composition.
Fish. Res. (2008)
Application of bioelectrical impedance analysis as a method for estimating composition and metabolic condition of southern bluefin tuna (Thunnus maccoyii) during conventional tagging
Jay Willis, Alistair J. Hobdaya
Tagging fish without gathering physiological informationmay be awasted opportunity.We tested bioelectrical impedance analysis (BIA) for measurement of relative condition of southern bluefin tuna (Thunnus maccoyii) during conventional tagging at sea. We refined the equipment and method by measurement of 360 fish during conventional and acoustic tagging. Our results demonstrate that BIA is an accurate measure of condition for southern bluefin tuna in the same way it has been shown to be for metabolic condition and composition in other vertebrates including humans. Further, there is sufficient variation in BIA measures of the natural population to give meaningful measures of both metabolic condition and composition between groups at different times and developmental stages. Condition of tuna in this study may be related to the ocean environment just prior to measurement. BIA meets the necessary objectives for measuring fish condition during tagging as it is shown to be harmless, reliable, quick, and effective and does not disrupt conventional tagging operations. In the light of these results this type of condition measurement should be taken wherever possible in future tagging operations for this and other similar species, which will generate new insight into the ecological challenges faced by pelagic fishes. The ability to relate recent ocean environments and subsequent patterns in fish survival may lead to changes in the way tagging data is interpreted.
J Physiol Anthropol Appl Human Sci. 2004 May;23(3):93-9. Fisheries Research 93 (2008) 64-71.
Application of bioelectrical impedance analysis as a method for estimating composition and metabolic condition of southern bluefin tuna (Thunnus maccoyii) during conventional tagging.
Jay Willisaa and Alistair J. Hobdayb
aSchool of Zoology & QMS, University of Tasmania, Hobart, Australia
bCSIRO Marine and Atmospheric Research, Castray Esplanade, Hobart, Tasmania, Australia
Tagging fish without gathering physiological information may be a wasted opportunity. We tested bioelectrical impedance analysis (BIA) for measurement of relative condition of southern bluefin tuna (Thunnus maccoyii) during conventional tagging at sea. We refined the equipment and method by measurement of 360 fish during conventional and acoustic tagging. Our results demonstrate that BIA is an accurate measure of condition for southern bluefin tuna in the same way it has been shown to be for metabolic condition and composition in other vertebrates including humans. Further, there is sufficient variation in BIA measures of the natural population to give meaningful measures of both metabolic condition and composition between groups at different times and developmental stages. Condition of tuna in this study may be related to the ocean environment just prior to measurement. BIA meets the necessary objectives for measuring fish condition during tagging as it is shown to be harmless, reliable, quick, and effective and does not disrupt conventional tagging operations. In the light of these results this type of condition measurement should be taken wherever possible in future tagging operations for this and other similar species, which will generate new insight into the ecological challenges faced by pelagic fishes. The ability to relate recent ocean environments and subsequent patterns in fish survival may lead to changes in the way tagging data is interpreted.
These papers and abstracts of papers have been published in peer-reviewed journals. They may draw conclusions and discuss applications of Bioelectrical Impedance Analysis which have not been reviewed by the FDA. Statements made within them are the sole responsibility of the authors. Unless otherwise indicated, no material support was provided to the authors or study investigators by RJL Systems.
