# Sea Bass (Dicentrarchus labrax) Tail-Beat Frequency Measurement Using Implanted Bioimpedance Sensing

^{1}

^{2}

^{3}

^{*}

## Abstract

**:**

**Key Contribution:**The first key contribution is the first experiment consisting of measuring bioimpedance in a moving animal. The second contribution is the tail-beat frequency estimation of seabass using bioimpedance, and the agreement analysis using video-based technique is the golden one.

## 1. Introduction

## 2. Bioimpedance Measurement Principle and Applications

## 3. Materials and Methods

#### 3.1. Ethical Approval

#### 3.2. Materials

#### 3.2.1. Animals

#### 3.2.2. Bioimpedance Measurement

#### 3.2.3. Respirometer

#### 3.2.4. Video

#### 3.3. Methods

#### 3.3.1. Surgery

^{−1}benzocaine (Benzocaine ethyl 4-Aminobenzoate, VWR, Rosny-sous-Bois, France, www.vwr.com) in aerated seawater until active ventilation ceased, then weighed and placed on their side on an operating table with their gills irrigated with aerated seawater containing $0.05$ $\mathrm{g}$ $\mathrm{L}$

^{−1}benzocaine. A one cm long vertical incision was made in the skin, halfway between the dorsal fin and the lateral line and at the level of the fourth dorsal fin ray, to reveal the underlying axial musculature. A blunt dissector was gently advanced under the skin to free it from the musculature and create a space into which the impedance electrode could be advanced. The electrode (cf. Figure 2A) was slid under the skin through the incision, which was closed with sutures to hold the electrode in place. The wires were then sutured firmly to the skin at the point of electrode insertion and again on the back of the fish, just anterior to the dorsal fin (cf. Figure 2B). After surgery, fish were left to recover for 24 $\mathrm{h}$ in a Steffensen-type swim tunnel respirometer (vol. 30 $\mathrm{L}$) provided with a flow of aerated, biofiltered, and UV-treated seawater at 21 °C, swimming in a current equivalent to 0.5 body lengths per second ($\mathrm{bl}$/$\mathrm{s}$) (cf. Figure 2C).

#### 3.3.2. Respirometer

#### 3.3.3. Bioimpedance Measurement

- Measurement setup: 4-point (4 pts) or 2-point (2 pts).
- Bioimpedance frequencies for each measurement: 100 $\mathrm{Hz}$, 1 $\mathrm{k}$$\mathrm{Hz}$, 10 $\mathrm{k}$$\mathrm{Hz}$, 100 $\mathrm{k}$$\mathrm{Hz}$, 1 $\mathrm{M}$$\mathrm{Hz}$, and 5 $\mathrm{M}$$\mathrm{Hz}$.

#### 3.4. Data Analysis

#### 3.4.1. Video

#### 3.4.2. Bioimpedance

#### 3.4.3. Statistical Analysis

## 4. Results

#### 4.1. Stride Length and Video-Based TBF versus Water Speed

#### 4.2. Bioimpedance-Based TBF Estimation in Relation to Swimming Speed

#### 4.3. Fish TBF Measurement, Video versus Bioimpedance

#### 4.3.1. Correlation and Agreement Considering Bioimpedance Setups and Resulting Electrical Parameters

- All t-tests for 4 pts setup measurements are 1 due to $p<0.01$. For 2 pts setup measurements, the t-test is equal to 0 for real parts and imaginary parts, with p-values of $0.32$ and $0.21$.
- The lowest CCC ($0.92$ and $0.94$) are for 2 pts setup for modulus and angle electrical parameters. For 4 pts setup, CCC are over $0.96$.

- r between $0.95$ and $0.98$.
- 95% limits of agreements between $[0.24,-0.30]$ and $[0.31,-0.41]$.
- CCC between $0.94$ and $0.97$.

#### 4.3.2. Correlation and Agreement Considering Different Frequencies of Bioimpedance Measurement

## 5. Discussion

^{−1}and 6 $\mathrm{S}$ $\mathrm{m}$

^{−1}[36], which is much higher than nominal fish conductivity (700 $\mu $$\mathrm{S}$ $\mathrm{m}$

^{−1}) [37]. This could have short-circuited the bioimpedance measurement. Based on the bioimpedance values and assuming that their variations were due to fish tailbeat activity, we can conclude that we measured fish bioimpedance. This was because the electrode contacts were oriented towards the inside of the muscle, and the electric field lines lost in the saltwater were limited due to the skin, which acts as an insulator.

- Accuracy using shorter measurement times and more advanced data processing techniques such as Short Time Fast Fourier Transform (STFFT).
- Response when the fish exhibits unsteady swimming with irregular tailbeats or turns.

- There is a need to instrument some fish with a biologger integrating a bioimpedance sensor in order to analyze the sensor response to some various behaviors resulting from free movements, such as burst swim and quick turn.
- Bioimpedance is known to be sensitive to temperature variations. Regarding TBF estimation using bioimpedance, we hypothesize that it would have only an impact on the signal amplitude, which shouldn’t affect the signal frequency estimation. Any way, a common solution is to integrate a temperature sensor in the electrode and calibrate the measurement according to temperature [44,45]
- One needed analysis regarding our newly proposed application is the effect of time. In order to be able to apply such an approach over a long time, there is a need for highly reliable electrodes that would resist repeated bendings in a harsh environment.

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Acknowledgments

## Conflicts of Interest

## Abbreviations

2 pts/4 pts | 2 points/4 points |

CCC | Concordance Correlation Coefficient |

CI1 | CCC lower limit of confidence interval |

CI2 | CCC upper limit of confidence interval |

FFT | Fast Fourier Transform |

freq | frequency |

ICC | Intraclass Correlation Coefficient |

LLOA | Lower Limit of the Interval |

mod | modulus |

STFFT | Short Time Fast Fourier Transform |

TBF | Tail-beat Frequency |

ULOA | Upper Limit of the Interval |

## References

- Videler, J.J. Fish Swimming; Springer: Dordrecht, The Netherlands, 1993. [Google Scholar] [CrossRef]
- Webb, P.W. Swimming. In The Physiologuy of Fishes; Evans, D., Ed.; CRC Press: Boca Raton, FL, USA, 1998; pp. 1–38. [Google Scholar]
- Bainbridge, R. The Speed of Swimming of Fish as Related to Size and to the Frequency and Amplitude of the Tail Beat. J. Exp. Biol.
**1958**, 35, 109–133. [Google Scholar] [CrossRef] - Gleiss, A.C.; Schallert, R.J.; Dale, J.J.; Wilson, S.G.; Block, B.A. Direct measurement of swimming and diving kinematics of giant Atlantic bluefin tuna (Thunnus thynnus). R. Soc. Open Sci.
**2019**, 6, 190203. [Google Scholar] [CrossRef] - Wardle, C.S. Limit of fish swimming speed. Nature
**1975**, 255, 725–727. [Google Scholar] [CrossRef] [PubMed] - Svendsen, M.B.S.; Domenici, P.; Marras, S.; Krause, J.; Boswell, K.M.; Rodriguez-Pinto, I.; Wilson, A.D.M.; Kurvers, R.H.J.M.; Viblanc, P.E.; Finger, J.S.; et al. Maximum swimming speeds of sailfish and three other large marine predatory fish species based on muscle contraction time and stride length: A myth revisited. Biol. Open
**2016**, 5, 1415–1419. [Google Scholar] [CrossRef] [PubMed] - Handegard, N.O.; Pedersen, G.; Brix, O. Estimating tail-beat frequency using split-beam echosounders. ICES J. Mar. Sci.
**2009**, 66, 1252–1258. [Google Scholar] [CrossRef] - Carbonara, P.; Alfonso, S.; Dioguardi, M.; Zupa, W.; Vazzana, M.; Dara, M.; Spedicato, M.T.; Lembo, G.; Cammarata, M. Calibrating accelerometer data, as a promising tool for health and welfare monitoring in aquaculture: Case study in European sea bass (Dicentrarchus labrax) in conventional or organic aquaculture. Aquac. Rep.
**2021**, 21, 100817. [Google Scholar] [CrossRef] - Cade, D.E.; Barr, K.R.; Calambokidis, J.; Friedlaender, A.S.; Goldbogen, J.A. Determining forward speed from accelerometer jiggle in aquatic environments. J. Exp. Biol.
**2018**, 221, jeb170449. [Google Scholar] [CrossRef] - Warren-Myers, F.; Svendsen, E.; Føre, M.; Folkedal, O.; Oppedal, F.; Hvas, M. Novel tag-based method for measuring tailbeat frequency and variations in amplitude in fish. Anim. Biotelemetry
**2023**, 11, 12. [Google Scholar] [CrossRef] - McKenzie, D.J.; Axelsson, M.; Chabot, D.; Claireaux, G.; Cooke, S.J.; Corner, R.A.; De Boeck, G.; Domenici, P.; Guerreiro, P.M.; Hamer, B.; et al. Conservation physiology of marine fishes: State of the art and prospects for policy. Conserv. Physiol.
**2016**, 4, cow046. [Google Scholar] [CrossRef] - Clarke, T.M.; Whitmarsh, S.K.; Hounslow, J.L.; Gleiss, A.C.; Payne, N.L.; Huveneers, C. Using tri-axial accelerometer loggers to identify spawning behaviours of large pelagic fish. Mov. Ecol.
**2021**, 9, 26. [Google Scholar] [CrossRef] - Kawabata, Y.; Noda, T.; Nakashima, Y.; Nanami, A.; Sato, T.; Takebe, T.; Mitamura, H.; Arai, N.; Yamaguchi, T.; Soyano, K. Use of a gyroscope/accelerometer data logger to identify alternative feeding behaviours in fish. J. Exp. Biol.
**2014**, 217, 3204–3208. [Google Scholar] [CrossRef] - Broell, F.; Taylor, A.D.; Litvak, M.K.; Bezanson, A.; Taggart, C.T. Post-tagging behaviour and habitat use in shortnose sturgeon measured with high-frequency accelerometer and PSATs. Anim. Biotelemetry
**2016**, 4, 11. [Google Scholar] [CrossRef] - Cruz-Font, L.; Shuter, B.J.; Blanchfield, P.J. Energetic costs of activity in wild lake trout: A calibration study using acceleration transmitters and positional telemetry. Can. J. Fish. Aquat. Sci.
**2016**, 73, 1237–1250. [Google Scholar] [CrossRef] - Zupa, W.; Alfonso, S.; Gai, F.; Gasco, L.; Spedicato, M.T.; Lembo, G.; Carbonara, P. Calibrating Accelerometer Tags with Oxygen Consumption Rate of Rainbow Trout (Oncorhynchus mykiss) and Their Use in Aquaculture Facility: A Case Study. Animals
**2021**, 11, 1496. [Google Scholar] [CrossRef] [PubMed] - Bouyoucos, I.A.; Montgomery, D.W.; Brownscombe, J.W.; Cooke, S.J.; Suski, C.D.; Mandelman, J.W.; Brooks, E.J. Swimming speeds and metabolic rates of semi-captive juvenile lemon sharks (Negaprion brevirostris, Poey) estimated with acceleration biologgers. J. Exp. Mar. Biol. Ecol.
**2017**, 486, 245–254. [Google Scholar] [CrossRef] - Grimnes, S.; Martinsen, Ø.G. (Eds.) Chapter 1—Introduction. In Bioimpedance and Bioelectricity Basics, 3rd ed.; Academic Press: Oxford, UK, 2015; pp. 1–7. [Google Scholar] [CrossRef]
- Khalil, S.F.; Mohktar, M.S.; Ibrahim, F. The Theory and Fundamentals of Bioimpedance Analysis in Clinical Status Monitoring and Diagnosis of Diseases. Sensors
**2014**, 14, 10895–10928. [Google Scholar] [CrossRef] - Willis, J.; Hobday, A.J. Application of bioelectrical impedance analysis as a method for estimating composition and metabolic condition of southern bluefin tuna (Thunnus maccoyii) during conventional tagging. Fish. Res.
**2008**, 93, 64–71. [Google Scholar] [CrossRef] - Zaniboni-Filho, E.; Hermes-Silva, S.; Weingartner, M.; Jimenez, J.E.; Borba, M.R.; Fracalossi, D.M. Bioimpedance as a tool for evaluating the body composition of suruvi (Steindachneridion scriptum). Braz. J. Biol.-Rev. Bras. Biol.
**2015**, 75. [Google Scholar] [CrossRef] - Mesa, M.G.; Rose, B.P. An assessment of morphometric indices, blood chemistry variables and an energy meter as indicators of the whole body lipid content in Micropterus dolomieu, Sander vitreus and Ictalurus punctatus. J. Fish Biol.
**2015**, 86, 755–764. [Google Scholar] [CrossRef] - Hafs, A.W.; Hartman, K.J. Developing bioelectrical impedance analysis methods for age-0 brook trout. Fish. Manag. Ecol.
**2014**, 21, 366–373. [Google Scholar] [CrossRef] - Khramtsova, N.I.; Plaksin, S.A. Two-electrode bioelectrical impedance measurement in body composition analysis before and after liposuction. In Proceedings of the 2016 IEEE International Symposium on Medical Measurements and Applications (MeMeA), Benevento, Italy, 15–18 May 2016; pp. 1–5. [Google Scholar] [CrossRef]
- Robert, M.; Dagorn, L.; Bodin, N.; Pernet, F.; Arsenault-Pernet, E.J.; Deneubourg, J.L. Comparison of condition factors of skipjack tuna (Katsuwonus pelamis) associated or not with floating objects in an area known to be naturally enriched with logs. Can. J. Fish. Aquat. Sci.
**2014**, 71, 472–478. [Google Scholar] [CrossRef] - Blanco-Almazán, D.; Groenendaal, W.; Catthoor, F.; Jané, R. Chest Movement and Respiratory Volume both Contribute to Thoracic Bioimpedance during Loaded Breathing. Sci. Rep.
**2019**, 9, 20232. [Google Scholar] [CrossRef] [PubMed] - Detrez, E.; Kerzérho, V.; Belhaj, M.M.; Vergnet, A.; de Verdal, H.; Rouyer, T.; Bonhommeau, S.; Lamlih, A.; Julien, M.; Ben Ali, F.; et al. Study differentiating fish oocyte developmental stages using bioimpedance spectroscopy. Aquaculture
**2022**, 547, 737396. [Google Scholar] [CrossRef] - Ranganathan, P.; Pramesh, C.S.; Aggarwal, R. Common pitfalls in statistical analysis: Measures of agreement. Perspect. Clin. Res.
**2017**, 8, 187. [Google Scholar] [CrossRef] [PubMed] - Watson, P.; Petrie, A. Method agreement analysis: A review of correct methodology. Theriogenology
**2010**, 73, 1167–1179. [Google Scholar] [CrossRef] - Martin Bland, J.; Altman, D. Statistical Methods for Assessing Agreement between Two Methods of Clinical Measurement. Lancet
**1986**, 327, 307–310. [Google Scholar] [CrossRef] - Rik. BlandAltmanPlot. 2021. Available online: https://fr.mathworks.com/matlabcentral/fileexchange/71052-blandaltmanplot/ (accessed on 19 September 2023).
- Lin, L.I.K. A Concordance Correlation Coefficient to Evaluate Reproducibility. Biometrics
**1989**, 45, 255–268. [Google Scholar] [CrossRef] - Matthew, R. f_CCC. 2018. Available online: https://fr.mathworks.com/matlabcentral/fileexchange/66896-f_ccc (accessed on 19 September 2023).
- Georgopoulou, D.G.; Stavrakidis-Zachou, O.; Mitrizakis, N.; Papandroulakis, N. Tracking and Analysis of the Movement Behavior of European Seabass (Dicentrarchus labrax) in Aquaculture Systems. Front. Anim. Sci.
**2021**, 2, 754520. [Google Scholar] [CrossRef] - Marras, S.; Killen, S.S.; Domenici, P.; Claireaux, G.; McKenzie, D.J. Relationships among Traits of Aerobic and Anaerobic Swimming Performance in Individual European Sea Bass Dicentrarchus labrax. PLoS ONE
**2013**, 8, e72815. [Google Scholar] [CrossRef] - Tyler, R.H.; Boyer, T.P.; Minami, T.; Zweng, M.M.; Reagan, J.R. Electrical conductivity of the global ocean. Earth Planets Space
**2017**, 69, 156. [Google Scholar] [CrossRef] - Kolz, A.L. Electrical Conductivity as Applied to Electrofishing. Trans. Am. Fish. Soc.
**2006**, 135, 509–518. [Google Scholar] [CrossRef] - Lamlih, A.; Freitas, P.; Belhaj, M.M.; Salles, J.; Kerzérho, V.; Soulier, F.; Bernard, S.; Rouyer, T.; Bonhommeau, S. A Hybrid Bioimpedance Spectroscopy Architecture for a Wide Frequency Exploration of Tissue Electrical Properties. In Proceedings of the 2018 IFIP/IEEE International Conference on Very Large Scale Integration (VLSI-SoC), Verona, Italy, 8–10 October 2018; pp. 168–171. [Google Scholar] [CrossRef]
- Analog Devices Impedance Measurement Products List. Available online: https://www.analog.com/en/solutions/instrumentation-and-measurement/electronic-test-and-measurement/impedance-measurement-and-analysis.html (accessed on 29 September 2024).
- Kerzérho, V.; Azaïs, F.; Bernard, S.; Bonhommeau, S.; Brisset, B.; De Knyff, L.; Julien, M.; Renovell, M.; Rouyer, T.; Saraux, C.; et al. Multilinear Regression Analysis between Local Bioimpedance Spectroscopy and Fish Morphological Parameters. Fishes
**2023**, 8, 88. [Google Scholar] [CrossRef] - Hartman, K.J.; Margraf, F.J.; Hafs, A.W.; Cox, M.K. Bioelectrical Impedance Analysis: A New Tool for Assessing Fish Condition. Fisheries
**2015**, 40, 590–600. [Google Scholar] [CrossRef] - Pothoven, S.A.; Ludsin, S.A.; Höök, T.O.; Fanslow, D.L.; Mason, D.M.; Collingsworth, P.D.; Van Tassell, J.J. Reliability of Bioelectrical Impedance Analysis for Estimating Whole-Fish Energy Density and Percent Lipids. Trans. Am. Fish. Soc.
**2008**, 137, 1519–1529. [Google Scholar] [CrossRef] - Duncan, M.; Craig, S.R.; Lunger, A.N.; Kuhn, D.D.; Salze, G.; McLean, E. Bioimpedance assessment of body composition in cobia Rachycentron canadum (L. 1766). Aquaculture
**2007**, 271, 432–438. [Google Scholar] [CrossRef] - Ruiz-Vargas, A.; Ivorra, A.; Arkwright, J.W. Design, Construction and Validation of an Electrical Impedance Probe with Contact Force and Temperature Sensors Suitable for in-vivo Measurements. Sci. Rep.
**2018**, 8, 14818. [Google Scholar] [CrossRef] - Leung, T.K.W.; Ji, X.; Peng, B.; Chik, G.K.K.; Dai, D.S.H.S.; Fang, G.; Zhang, T.; Cheng, X.; Kwok, K.W.; Tsang, A.C.O.; et al. Micro-electrodes for in situ temperature and bio-impedance measurement. Nano Select
**2021**, 2, 1986–1996. [Google Scholar] [CrossRef]

**Figure 2.**(

**A**) The flexible biocompatible 4-contact electrode for bioimpedance measurement; (

**B**) Fish after surgery for implantation of the electrode; (

**C**) post-surgery fish recovery in the Steffensen-type swim tunnel.

**Figure 4.**(

**A**) stride length ($\mathrm{bl}$) versus water speed ($\mathrm{bl}$/$\mathrm{s}$), (

**B**) video-based estimation of TBF ($\mathrm{Hz}$) versus water speed ($\mathrm{bl}$/$\mathrm{s}$) at 5 water speeds.

**Figure 5.**Plotter graph example: variation of the modulus of the bioimpedance over the 16 $\mathrm{s}$ measurement for two fishes. The water speed is 1.25 bl/s, the bioimpedance measurement setup is 4 pts, and the bioimpedance frequency measurement is 1 $\mathrm{k}$$\mathrm{Hz}$.

**Figure 6.**Water speed versus bioimpedance-based TBF estimation for fish 2 (

**a**) 4 pts modulus of bioimpedance for frequency estimation; (

**b**) 4 pts angle of bioimpedance for frequency estimation; (

**c**) 2 pts modulus of bioimpedance for frequency estimation, (

**d**) 2 pts angle of bioimpedance for frequency estimation.

**Figure 7.**t-test p-value for the 4 pts and 2 pts setups and eight combinations of electrical parameters.

**Figure 8.**t-test p-value for the 4 pts setup, two electrical parameters, and six bioimpedance frequencies.

**Table 1.**Statistical analysis results bioimpedance-based estimation of TBF for the two setups (4 pts yellow, 2 pts red) and the four electrical parameters (mod, angle, real, imag).

Bioimpedance Setup and Parameter | r | $\mathit{\mu}$ | ULOA | LLOA | t-Test | t-Test p | CCC | CI1 | CI2 |
---|---|---|---|---|---|---|---|---|---|

4 pts mod | 0.97 | −0.03 | 0.24 | −0.30 | 1 | 0 | 0.97 | 0.96 | 0.98 |

4 pts angle | 0.97 | −0.03 | 0.26 | −0.32 | 1 | 0.01 | 0.96 | 0.95 | 0.97 |

2 pts mod | 0.95 | −0.06 | 0.29 | −0.39 | 1 | 0 | 0.94 | 0.92 | 0.96 |

2 pts angle | 0.93 | −0.05 | 0.37 | −0.46 | 1 | 0.01 | 0.92 | 0.89 | 0.94 |

4 pts real | 0.97 | −0.03 | 0.24 | −0.30 | 1 | 0.01 | 0.97 | 0.96 | 0.98 |

4 pts imag | 0.97 | −0.03 | 0.26 | −0.32 | 1 | 0.01 | 0.96 | 0.95 | 0.97 |

2 pts real | 0.97 | −0.01 | 0.26 | −0.29 | 0 | 0.32 | 0.97 | 0.95 | 0.97 |

2 pts imag | 0.96 | −0.02 | 0.29 | −0.33 | 0 | 0.21 | 0.96 | 0.94 | 0.97 |

**Table 2.**Statistical analysis results, bioimpedance-based estimation of TBF for the two setups (4 pts yellow, 2 pts red), and the mean of two to four electrical parameters.

Bioimpedance Setup and Mean of Parameters | r | $\mathit{\mu}$ | ULOA | LLOA | t-Test | t-Test p | CCC | CI1 | CI2 |
---|---|---|---|---|---|---|---|---|---|

4 pts mean (mod, angle) | 0.98 | −0.03 | 0.24 | −0.30 | 1 | 0.01 | 0.97 | 0.96 | 0.98 |

4 pts mean (real, imag) | 0.97 | −0.03 | 0.24 | −0.30 | 1 | 0.01 | 0.97 | 0.96 | 0.98 |

4 pts mean (mod, real) | 0.97 | −0.03 | 0.24 | −0.30 | 1 | 0.01 | 0.97 | 0.96 | 0.98 |

4 pts mean (mod, angle, real, imag) | 0.97 | −0.03 | 0.24 | −0.30 | 1 | 0.01 | 0.97 | 0.96 | 0.98 |

2 pts mean (mod, angle) | 0.95 | −0.05 | 0.31 | −0.41 | 1 | 0 | 0.94 | 0.91 | 0.95 |

2 pts mean (real, imag) | 0.97 | −0.01 | 0.27 | −0.30 | 0 | 0.24 | 0.96 | 0.95 | 0.97 |

2 pts mean (mod, real) | 0.97 | −0.03 | 0.24 | −0.30 | 1 | 0 | 0.96 | 0.95 | 0.97 |

2 pts mean (mod, angle, real, imag) | 0.97 | −0.03 | 0.25 | −0.31 | 1 | 0.01 | 0.96 | 0.95 | 0.97 |

**Table 3.**Statistical analysis results (r: correlation coefficient, $\mu $: mean of the difference of estimations, ULOA: Bland and Altman upper limit of agreement, LLOA: Bland and Altman lower limit of agreement, ttest h: t-test result, ttest p: t-test p-value, CCC: Concordance Correlation Coefficient, CI1: CCC lower limit of confidence interval, CI2: CCC upper limit of confidence interval), bioimpedance-based estimation of TBF for the two setups (4 pts yellow, 2 pts red), two electrical parameters (mod and real) and each of the 6 bioimpedance frequencies (100 $\mathrm{Hz}$, 1$\mathrm{k}$$\mathrm{Hz}$, 10 $\mathrm{k}$$\mathrm{Hz}$, 100 $\mathrm{k}$$\mathrm{Hz}$, 1 $\mathrm{M}$$\mathrm{Hz}$, 5 $\mathrm{M}$$\mathrm{Hz}$).

Bioimpedance Setup, Parameter and Frequency Number | r | $\mathit{\mu}$ | ULOA | LLOA | t-Test | t-Test p | CCC | CI1 | CI2 |
---|---|---|---|---|---|---|---|---|---|

4 pts mod freq1 | 0.93 | 0.01 | 0.45 | −0.42 | 0 | 0.79 | 0.92 | 0.84 | 0.96 |

4 pts mod freq2 | 0.98 | −0.02 | 0.27 | −0.31 | 0 | 0.44 | 0.97 | 0.94 | 0.98 |

4 pts mod freq3 | 0.99 | −0.05 | 0.13 | −0.23 | 1 | 0.01 | 0.98 | 0.96 | 0.99 |

4 pts mod freq4 | 0.98 | −0.05 | 0.19 | −0.29 | 0 | 0.06 | 0.97 | 0.94 | 0.99 |

4 pts mod freq5 | 0.99 | −0.04 | 0.12 | −0.20 | 1 | 0.02 | 0.99 | 0.97 | 0.99 |

4 pts mod freq6 | 0.99 | −0.05 | 0.15 | −0.24 | 1 | 0.03 | 0.98 | 0.96 | 0.99 |

2 pts mod freq1 | 0.93 | 0.01 | 0.45 | −0.42 | 0 | 0.78 | 0.92 | 0.84 | 0.96 |

2 pts mod freq2 | 0.98 | −0.02 | 0.27 | −0.31 | 0 | 0.44 | 0.97 | 0.94 | 0.98 |

2 pts mod freq3 | 0.98 | −0.05 | 0.13 | −0.23 | 1 | 0.01 | 0.98 | 0.96 | 0.99 |

2 pts mod freq4 | 0.98 | −0.05 | 0.19 | −0.29 | 0 | 0.06 | 0.97 | 0.94 | 0.99 |

2 pts mod freq5 | 0.99 | −0.04 | 0.12 | −0.20 | 1 | 0.02 | 0.99 | 0.97 | 0.99 |

2 pts mod freq6 | 0.99 | −0.05 | 0.15 | −0.24 | 1 | 0.03 | 0.98 | 0.96 | 0.99 |

Disclaimer/Publisher’s Note: The statements, opinions and data contained in all publications are solely those of the individual author(s) and contributor(s) and not of MDPI and/or the editor(s). MDPI and/or the editor(s) disclaim responsibility for any injury to people or property resulting from any ideas, methods, instructions or products referred to in the content. |

© 2024 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).

## Share and Cite

**MDPI and ACS Style**

Kerzerho, V.; Belhaj, M.-M.; Bernard, S.; Bonhommeau, S.; Rouyer, T.; Soulier, F.; McKenzie, D.J.
Sea Bass (*Dicentrarchus labrax*) Tail-Beat Frequency Measurement Using Implanted Bioimpedance Sensing. *Fishes* **2024**, *9*, 399.
https://doi.org/10.3390/fishes9100399

**AMA Style**

Kerzerho V, Belhaj M-M, Bernard S, Bonhommeau S, Rouyer T, Soulier F, McKenzie DJ.
Sea Bass (*Dicentrarchus labrax*) Tail-Beat Frequency Measurement Using Implanted Bioimpedance Sensing. *Fishes*. 2024; 9(10):399.
https://doi.org/10.3390/fishes9100399

**Chicago/Turabian Style**

Kerzerho, Vincent, Mohamed-Moez Belhaj, Serge Bernard, Sylvain Bonhommeau, Tristan Rouyer, Fabien Soulier, and David J. McKenzie.
2024. "Sea Bass (*Dicentrarchus labrax*) Tail-Beat Frequency Measurement Using Implanted Bioimpedance Sensing" *Fishes* 9, no. 10: 399.
https://doi.org/10.3390/fishes9100399