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Adjei HO, Laar RY, Ofori-Darkwah P, Xatse EX, Bediako JO, Skov PV, Obirikorang KA. Air-breathing behavior in Heterotis niloticus fingerlings: Response to changes in oxygen, temperature, and exercise regimes. JOURNAL OF FISH BIOLOGY 2023; 103:1044-1053. [PMID: 37421412 DOI: 10.1111/jfb.15502] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Revised: 07/06/2023] [Accepted: 07/07/2023] [Indexed: 07/10/2023]
Abstract
Air-breathing in fish is believed to have arisen as an adaptation to aquatic hypoxia. Although air-breathing has been widely studied in numerous fish species, little is known about the obligate air-breathing African bonytongue, Heterotis niloticus. We evaluated if abiotic factors and physical activity affect air-breathing patterns in fingerlings. The air-breathing frequency (fAB ) and behavioral responses of H. niloticus fingerlings were assessed in response to environmental oxygen, temperature, and exhaustion and activity in a series of experiments. The air-breathing behavior of H. niloticus fingerlings under optimum water conditions was characterized by swift excursions lasting less than 1 s to the air-water interface to gulp air. The intervals between air-breaths were highly variable, ranging from 3 to 259 s. Body size only slightly affected fAB , while hypoxia, hyperthermia, and exercise stress significantly increased fAB . Progressive hypoxia from 17.69 to 2.17 kPa caused a ~2.5-fold increase in fAB . Increasing temperatures to 27 and 32°C, from a baseline temperature of 22°C, significantly increased fAB from 0.4 ± 0.2 to 1.3 ± 0.5 and 1.6 ± 0.4 breaths min-1 , respectively. Lastly, following exhaustive exercise, fAB increased up to 3-fold. These observations suggest that H. niloticus fingerlings are very reliant on aerial oxygen, and their air-breathing behavior is sensitive to environmental changes and activity levels.
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Affiliation(s)
- Henry Owusu Adjei
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Robert Yadama Laar
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Prince Ofori-Darkwah
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Emmanuel Xorla Xatse
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Jedida Osei Bediako
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | - Peter Vilhelm Skov
- Technical University of Denmark, DTU Aqua, Section for Aquaculture, The North Sea Research Centre, Hirtshals, Denmark
| | - Kwasi Adu Obirikorang
- Department of Fisheries and Watershed Management, Faculty of Renewable Natural Resources, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
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Larentis C, Kotz Kliemann BC, Neves MP, Delariva RL. Effects of human disturbance on habitat and fish diversity in Neotropical streams. PLoS One 2022; 17:e0274191. [PMID: 36084014 PMCID: PMC9462761 DOI: 10.1371/journal.pone.0274191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2021] [Accepted: 08/23/2022] [Indexed: 11/27/2022] Open
Abstract
Human pressures have been intensely modifying freshwater ecosystems worldwide. We assessed the effects of human pressure on habitat diversity and primary productivity to understand the consequences on fish fauna in 25 tropical and subtropical streams of two globally important ecoregions: Iguassu and Upper Paraná. We hypothesized that the increased human pressure (urbanization and agriculture) on stream environments, both at the local and catchment scales, directly decreases habitat diversity. We also hypothesized that increased human pressure triggers changes in primary productivity and fish fauna composition and structure. We evaluated the human pressure intensity using the Integrated Disturbance Index and the Rapid Habitat Diversity Assessment protocol, which combines information about land use, land cover and environmental characteristics of the stream catchment and sampling sites. Streams with increased human disturbance had lower habitat diversity, higher primary productivity, and high non-native species abundance. Fish compositional turnover was associated with increased human disturbance. Native and degradation-sensitive fish species, especially endemic ones, were associated with streams with higher habitat diversity and forested cover. Degradation-resistant fishes, mostly non-native species, were associated with streams with higher human disturbance and urban land use. Although human pressure did not affect species richness, Shannon diversity, and Simpson dominance, there were significant effects on numerical abundance and fish species equitability. In this study, human pressure directly affected habitat structure, with indirect consequences for fish fauna, increasing the potential for local extirpation of rare species.
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Affiliation(s)
- Crislei Larentis
- Programa de Pós-Graduação em Biologia Comparada, Universidade Estadual de Maringá, Maringá, Paraná, Brazil
| | - Bruna Caroline Kotz Kliemann
- Programa de Pós-graduação em Ciências Biológicas/Zoologia, Instituto de Biociências, Universidade Estadual Paulista (UNESP), Botucatu, São Paulo, Brazil
| | - Mayara Pereira Neves
- Programa de Pós-graduação em Biologia Animal, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Rosilene Luciana Delariva
- Laboratório de Ictiologia, Ecologia e Biomonitoramentos (LIEB), Universidade Estadual do Oeste do Paraná – UNIOESTE, Cascavel, Paraná, Brazil
- * E-mail:
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Oufiero CE, Kraskura K, Bennington R, Nelson JA. Individual Repeatability of Locomotor Kinematics and Swimming Performance in a Gymnotiform Swimmer. Physiol Biochem Zool 2020; 94:22-34. [PMID: 33275536 DOI: 10.1086/712058] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
AbstractGymnotiform swimming is a specialized form of swimming wherein thrust is produced by the ribbonlike motion of an elongate anal fin, while the body is held relatively stiff. This form of swimming has been extensively examined in relation to the biomechanics of thrust production, the kinematics of the anal fin, and neuromuscular control, whereas few studies have examined whole-animal performance parameters of this swimming mode. The goals of this research were to (1) assess the maximum abilities and repeatability of two swimming performance measures, sprinting and prolonged swimming, which would indicate that these performance measures in a gymnotiform swimmer may be a target for selection, similar to body-caudal fin-swimming fish; (2) examine how a gymnotiform swimmer modulates swimming speed; and (3) determine whether modulatory behavior is consistent across different-sized fish and within individuals across time. Sprinting and prolonged swimming were examined in black ghost knifefish (Apteronotus albifrons; N=15), multiple times on the same day, and were measured again 4 wk later. Sprinting ability was measured by chasing a fish down a photocell-lined racetrack and obtaining the fastest speed between any 8-cm span. Prolonged swimming abilities were measured in a constant acceleration test (Ucat) in a Brett-style swim tunnel by measuring the maximum speed the fish could attain against a steadily increasing water velocity. We determined frequency, wavelength, and amplitude of the anal fin sine wave in fish swimming at different speeds during the Ucat trials. We found repeatable measures of sprint speed and Ucat performance over short (day) and medium (4 wk) time periods for both tests. Neither sprint nor Ucat performance was significantly dependent on size, suggesting that the primary driver of performance variation was individual differences in physiology. Most modulation of swimming speed occurred through changes in the frequency of the wave train processing down the anal fin, with only modest changes to the wavelength and minimal changes to amplitude. Finally, we compare our measures of swimming performance in this gymnotiform swimmer to published values of body-caudal fin swimmers to demonstrate that this form of locomotion results in comparable sprint and constant-acceleration values.
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Blasco FR, Esbaugh AJ, Killen SS, Rantin FT, Taylor EW, McKenzie DJ. Using aerobic exercise to evaluate sub-lethal tolerance of acute warming in fishes. ACTA ACUST UNITED AC 2020; 223:jeb.218602. [PMID: 32381588 PMCID: PMC7225124 DOI: 10.1242/jeb.218602] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Accepted: 03/01/2020] [Indexed: 01/10/2023]
Abstract
We investigated whether fatigue from sustained aerobic swimming provides a sub-lethal endpoint to define tolerance of acute warming in fishes, as an alternative to loss of equilibrium (LOE) during a critical thermal maximum (CTmax) protocol. Two species were studied, Nile tilapia (Oreochromis niloticus) and pacu (Piaractus mesopotamicus). Each fish underwent an incremental swim test to determine gait transition speed (U GT), where it first engaged the unsteady anaerobic swimming mode that preceded fatigue. After suitable recovery, each fish was exercised at 85% of their own U GT and warmed 1°C every 30 min, to identify the temperature at which they fatigued, denoted as CTswim Fish were also submitted to a standard CTmax, warming at the same rate as CTswim, under static conditions until LOE. All individuals fatigued in CTswim, at a mean temperature approximately 2°C lower than their CTmax Therefore, if exposed to acute warming in the wild, the ability to perform aerobic metabolic work would be constrained at temperatures significantly below those that directly threatened survival. The collapse in performance at CTswim was preceded by a gait transition qualitatively indistinguishable from that during the incremental swim test. This suggests that fatigue in CTswim was linked to an inability to meet the tissue oxygen demands of exercise plus warming. This is consistent with the oxygen and capacity limited thermal tolerance (OCLTT) hypothesis, regarding the mechanism underlying tolerance of warming in fishes. Overall, fatigue at CTswim provides an ecologically relevant sub-lethal threshold that is more sensitive to extreme events than LOE at CTmax.
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Affiliation(s)
- Felipe R Blasco
- Department of Physiological Sciences, Federal University of São Carlos, 13565-905 São Carlos, SP, Brazil .,Joint Graduate Program in Physiological Sciences, Federal University of São Carlos - UFSCar/São Paulo State University, UNESP Campus Araraquara, 14801-903 Araraquara, SP, Brazil
| | - Andrew J Esbaugh
- Marine Science Institute, University of Texas at Austin, Austin, TX 78373, USA
| | - Shaun S Killen
- Institute of Biodiversity, Animal Health & Comparative Medicine, College of Medical, Veterinary & Life Sciences, University of Glasgow, Glasgow G12 8QQ, UK
| | - Francisco Tadeu Rantin
- Department of Physiological Sciences, Federal University of São Carlos, 13565-905 São Carlos, SP, Brazil
| | - Edwin W Taylor
- Department of Physiological Sciences, Federal University of São Carlos, 13565-905 São Carlos, SP, Brazil.,School of Biosciences, University of Birmingham, Birmingham B15 2TT, UK
| | - David J McKenzie
- Department of Physiological Sciences, Federal University of São Carlos, 13565-905 São Carlos, SP, Brazil.,MARBEC, Université de Montpellier, CNRS, Ifremer, IRD, 34000 Montpellier, France
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Damsgaard C, Baliga VB, Bates E, Burggren W, McKenzie DJ, Taylor E, Wright PA. Evolutionary and cardio-respiratory physiology of air-breathing and amphibious fishes. Acta Physiol (Oxf) 2020; 228:e13406. [PMID: 31630483 DOI: 10.1111/apha.13406] [Citation(s) in RCA: 39] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2019] [Revised: 09/28/2019] [Accepted: 10/17/2019] [Indexed: 12/24/2022]
Abstract
Air-breathing and amphibious fishes are essential study organisms to shed insight into the required physiological shifts that supported the full transition from aquatic water-breathing fishes to terrestrial air-breathing tetrapods. While the origin of air-breathing in the evolutionary history of the tetrapods has received considerable focus, much less is known about the evolutionary physiology of air-breathing among fishes. This review summarizes recent advances within the field with specific emphasis on the cardiorespiratory regulation associated with air-breathing and terrestrial excursions, and how respiratory physiology of these living transitional forms are affected by development and personality. Finally, we provide a detailed and re-evaluated model of the evolution of air-breathing among fishes that serves as a framework for addressing new questions on the cardiorespiratory changes associated with it. This review highlights the importance of combining detailed studies on piscine air-breathing model species with comparative multi-species studies, to add an additional dimension to our understanding of the evolutionary physiology of air-breathing in vertebrates.
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Affiliation(s)
| | - Vikram B. Baliga
- Department of Zoology University of British Columbia Vancouver BC Canada
| | - Eric Bates
- Derailleur Interactive Vancouver BC Canada
| | - Warren Burggren
- Department of Biological Sciences University of North Texas Denton TX USA
| | - David J. McKenzie
- UMR Marbec, CNRS, IRD, Ifremer Université Montpellier Montpellier France
| | - Edwin Taylor
- School of Biosciences University of Birmingham Birmingham UK
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6
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George AB, Westneat MW. Functional morphology of endurance swimming performance and gait transition strategies in balistoid fishes. J Exp Biol 2019; 222:jeb.194704. [DOI: 10.1242/jeb.194704] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2018] [Accepted: 04/02/2019] [Indexed: 11/20/2022]
Abstract
Triggerfishes and filefishes (Balistoidea) use balistiform locomotion to power steady swimming with their dorsal and anal fins and transition to a gait dominated by body and caudal fin (BCF) kinematics at high speeds. Fin and body shapes are predicted to be strong determinants of swimming performance and gait transitions. The goal of this study was to combine morphometrics and critical swimming tests to explore relationships between fin and body shapes and swimming performance in a phylogenetic context in order to understand the evolution of balistiform swimming. Among 13 species of balistoid fishes, those with high aspect ratio fins tended to achieve higher critical swimming speeds than fishes with low aspect ratio fins. Species with long, large median fins and wide caudal peduncles used the balistiform gait alone for a larger percentage of their total critical swimming speed than fishes with short, small median fins and narrow caudal peduncles. Although analyses revealed overall positive relationships between median fin aspect ratios and gait transition speeds, fishes on both ends of the aspect ratio spectrum achieved higher swimming speeds using the balistiform gait alone than fishes with median fins of intermediate aspect ratios. Each species is specialized for taking advantage of one gait, with balistiform specialists possessing long, large median fins capable of the large power requirements of high-speed swimming using the median fins alone, while BCF specialists possess short, small median fins, ill-suited for powering high-speed balistiform locomotion, but narrow caudal peduncles capable of efficient caudal fin oscillations to power high-speed locomotion.
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Affiliation(s)
- Andrew B. George
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois 60615, USA
| | - Mark W. Westneat
- Department of Organismal Biology and Anatomy, University of Chicago, Chicago, Illinois 60615, USA
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Whitlow KR, Santini F, Oufiero CE. Convergent evolution of locomotor morphology but not performance in gymnotiform swimmers. J Evol Biol 2018; 32:76-88. [DOI: 10.1111/jeb.13399] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Revised: 11/01/2018] [Accepted: 11/02/2018] [Indexed: 11/29/2022]
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8
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Florindo LH, Armelin VA, McKenzie DJ, Rantin FT. Control of air-breathing in fishes: Central and peripheral receptors. Acta Histochem 2018; 120:642-653. [PMID: 30219242 DOI: 10.1016/j.acthis.2018.08.010] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
This review considers the environmental and systemic factors that can stimulate air-breathing responses in fishes with bimodal respiration, and how these may be controlled by peripheral and central chemoreceptors. The systemic factors that stimulate air-breathing in fishes are usually related to conditions that increase the O2 demand of these animals (e.g. physical exercise, digestion and increased temperature), while the environmental factors are usually related to conditions that impair their capacity to meet this demand (e.g. aquatic/aerial hypoxia, aquatic/aerial hypercarbia, reduced aquatic hidrogenionic potential and environmental pollution). It is now well-established that peripheral chemoreceptors, innervated by cranial nerves, drive increased air-breathing in response to environmental hypoxia and/or hypercarbia. These receptors are, in general, sensitive to O2 and/or CO2/H+ levels in the blood and/or the environment. Increased air-breathing in response to elevated O2 demand may also be driven by the peripheral chemoreceptors that monitor O2 levels in the blood. Very little is known about central chemoreception in air-breathing fishes, the data suggest that central chemosensitivity to CO2/H+ is more prominent in sarcopterygians than in actinopterygians. A great deal remains to be understood about control of air-breathing in fishes, in particular to what extent control systems may show commonalities (or not) among species or groups that have evolved air-breathing independently, and how information from the multiple peripheral (and possibly central) chemoreceptors is integrated to control the balance of aerial and aquatic respiration in these animals.
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Affiliation(s)
- Luiz Henrique Florindo
- Department of Zoology and Botany, São Paulo State University (UNESP), Rua Cristóvão Colombo, 2265, São José do Rio Preto, SP, 15054-000, Brazil; Aquaculture Center (CAUNESP), São Paulo State University (UNESP), Rodovia Prof. Paulo Donato Castellane, n/n, Jaboticabal, SP, 14884-900, Brazil
| | - Vinicius Araújo Armelin
- Department of Zoology and Botany, São Paulo State University (UNESP), Rua Cristóvão Colombo, 2265, São José do Rio Preto, SP, 15054-000, Brazil
| | - David John McKenzie
- Centre for Marine Biodiversity Exploitation and Conservation, UMR9190 (IRD, Ifremer, UM, CNRS), Université Montpellier, Place Eugène Bataillon cc 093, 34095 Montpellier Cedex 5, France; Department of Physiological Sciences, Federal University of São Carlos (UFSCar), Rodovia Washington Luiz, km 235, São Carlos, SP, 13565-905, Brazil
| | - Francisco Tadeu Rantin
- Department of Physiological Sciences, Federal University of São Carlos (UFSCar), Rodovia Washington Luiz, km 235, São Carlos, SP, 13565-905, Brazil.
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Yuan X, Huang YP, Cai L, Johnson D, Tu ZY, Zhou YH. Physiological responses to swimming fatigue in juvenile largemouth bronze gudgeon Coreius guichenoti. JOURNAL OF FISH BIOLOGY 2018; 92:1192-1197. [PMID: 29465159 DOI: 10.1111/jfb.13557] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 01/08/2018] [Indexed: 06/08/2023]
Abstract
Stepped velocity tests were conducted on juvenile largemouth bronze gudgeon Coreius guichenoti in a swim tunnel respirometer, and oxygen consumption increased with swimming speed to fatigue and then decreased during recovery. Serum levels of total protein, glucose and triglycerides initially decreased, increased at fatigue and then decreased during recovery. Levels stabilized after 120 min, corresponding to the time necessary to recover from fatigue.
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Affiliation(s)
- X Yuan
- Engineering Research Center of Eco-environment in Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Yichang, 443002, China
- College of Hydraulic & Environmental Engineering, China Three Gorges University, Yichang, 443002, China
| | - Y P Huang
- Engineering Research Center of Eco-environment in Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Yichang, 443002, China
| | - L Cai
- Institute of Hydroecology, Ministry of Water Resources and Chinese Academy of Sciences, Wuhan, 430079, China
| | - D Johnson
- Engineering Research Center of Eco-environment in Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Yichang, 443002, China
- Institute of Hydroecology, Ministry of Water Resources and Chinese Academy of Sciences, Wuhan, 430079, China
- School of Natural Sciences and Mathematics, Ferrum College, Ferrum, Virginia, 24088, U.S.A
| | - Z Y Tu
- Engineering Research Center of Eco-environment in Three Gorges Reservoir Region, Ministry of Education, China Three Gorges University, Yichang, 443002, China
| | - Y H Zhou
- College of Hydraulic & Environmental Engineering, China Three Gorges University, Yichang, 443002, China
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Clown knifefish ( Chitala ornata ) oxygen uptake and its partitioning in present and future temperature environments. Comp Biochem Physiol A Mol Integr Physiol 2018; 216:52-59. [DOI: 10.1016/j.cbpa.2017.11.018] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2017] [Revised: 11/24/2017] [Accepted: 11/28/2017] [Indexed: 11/21/2022]
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Killen SS, Esbaugh AJ, F. Martins N, Tadeu Rantin F, McKenzie DJ, Farine D. Aggression supersedes individual oxygen demand to drive group air-breathing in a social catfish. J Anim Ecol 2018; 87:223-234. [PMID: 28940526 PMCID: PMC5765462 DOI: 10.1111/1365-2656.12758] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2017] [Accepted: 08/31/2017] [Indexed: 02/01/2023]
Abstract
Group-living is widespread among animals and comes with numerous costs and benefits. To date, research examining group-living has focused on trade-offs surrounding foraging, while other forms of resource acquisition have been largely overlooked. Air-breathing has evolved in many fish lineages, allowing animals to obtain oxygen in hypoxic aquatic environments. Breathing air increases the threat of predation, so some species perform group air-breathing, to reduce individual risk. Within species, individual air-breathing can be influenced by metabolic rate as well as personality, but the mechanisms of group air-breathing remain unexplored. It is conceivable that keystone individuals with high metabolic demand or intrinsic tendency to breathe air may drive social breathing, especially in hypoxia. We examined social air-breathing in African sharptooth catfish Clarias gariepinus, to determine whether individual physiological traits and spontaneous tendency to breathe air influence the behaviour of entire groups, and whether such influences vary in relation to aquatic oxygen availability. We studied 11 groups of four catfish in a laboratory arena and recorded air-breathing behaviour, activity and agonistic interactions at varying levels of hypoxia. Bimodal respirometry was used to estimate individual standard metabolic rate (SMR) and the tendency to utilize aerial oxygen when alone. Fish took more air breaths in groups as compared to when they were alone, regardless of water oxygen content, and displayed temporally clustered air-breathing behaviour, consistent with existing definitions of synchronous air-breathing. However, groups displayed tremendous variability in surfacing behaviour. Aggression by dominant individuals within groups was the main factor influencing air-breathing of the entire group. There was no association between individual SMR, or the tendency to obtain oxygen from air when in isolation, and group air-breathing. For C. gariepinus, synchronous air-breathing is strongly influenced by agonistic interactions, which may expose subordinate individuals to risk of predation. Influential individuals exerted an overriding effect on risk-taking by the entire group, for reasons independent of their physiological oxygen requirements. Overall, this illustrates that social context can obscure interactions between an individual's physiological and behavioural traits and their tendency to take risks to obtain resources.
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Affiliation(s)
- Shaun S. Killen
- Institute of Biodiversity, Animal Health and Comparative MedicineCollege of Medical, Veterinary and Life SciencesUniversity of GlasgowGlasgowUK
| | - Andrew J. Esbaugh
- Department of Marine ScienceMarine Science InstituteUniversity of Texas at AustinPort AransasTXUSA
| | - Nicolas F. Martins
- Department of Physiological SciencesFederal University of São CarlosSão CarlosBrazil
| | - F. Tadeu Rantin
- Department of Physiological SciencesFederal University of São CarlosSão CarlosBrazil
| | - David J. McKenzie
- Department of Physiological SciencesFederal University of São CarlosSão CarlosBrazil
- Centre for Marine Biodiversity Exploitation and ConservationUMR9190 (IRD, Ifremer, UM, CNRS)Université MontpellierMontpellier Cedex 5France
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12
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Tian R, Losilla M, Lu Y, Yang G, Zakon H. Molecular evolution of globin genes in Gymnotiform electric fishes: relation to hypoxia tolerance. BMC Evol Biol 2017; 17:51. [PMID: 28193153 PMCID: PMC5307702 DOI: 10.1186/s12862-017-0893-3] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2016] [Accepted: 01/26/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Nocturnally active gymnotiform weakly electric fish generate electric signals for communication and navigation, which can be energetically taxing. These fish mainly inhabit the Amazon basin, where some species prefer well-oxygenated waters and others live in oxygen-poor, stagnant habitats. The latter species show morphological, physiological, and behavioral adaptations for hypoxia-tolerance. However, there have been no studies of hypoxia tolerance on the molecular level. Globins are classic respiratory proteins. They function principally in oxygen-binding and -delivery in various tissues and organs. Here, we investigate the molecular evolution of alpha and beta hemoglobins, myoglobin, and neuroglobin in 12 gymnotiforms compared with other teleost fish. RESULTS The present study identified positively selected sites (PSS) on hemoglobin (Hb) and myoglobin (Mb) genes using different maximum likelihood (ML) methods; some PSS fall in structurally important protein regions. This evidence for the positive selection of globin genes suggests that the adaptive evolution of these genes has helped to enhance the capacity for oxygen storage and transport. Interestingly, a substitution of a Cys at a key site in the obligate air-breathing electric eel (Electrophorus electricus) is predicted to enhance oxygen storage of Mb and contribute to NO delivery during hypoxia. A parallel Cys substitution was also noted in an air-breathing African electric fish (Gymnarchus niloticus). Moreover, the expected pattern under normoxic conditions of high expression of myoglobin in heart and neuroglobin in the brain in two hypoxia-tolerant species suggests that the main effect of selection on these globin genes is on their sequence rather than their basal expression patterns. CONCLUSION Results indicate a clear signature of positive selection in the globin genes of most hypoxia-tolerant gymnotiform fishes, which are obligate or facultative air breathers. These findings highlight the critical role of globin genes in hypoxia tolerance evolution of Gymnotiform electric fishes.
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Affiliation(s)
- Ran Tian
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, 210046, China
- Department of Integrative Biology, The University of Texas, Austin, TX, 78759, USA
| | - Mauricio Losilla
- Department of Integrative Biology, Michigan State University, East Lansing, MI, 48824, USA
| | - Ying Lu
- Department of Integrative Biology, The University of Texas, Austin, TX, 78759, USA
- Department of Neuroscience, The University of Texas, Austin, TX, 78759, USA
| | - Guang Yang
- Jiangsu Key Laboratory for Biodiversity and Biotechnology, College of Life Sciences, Nanjing Normal University, Nanjing, 210046, China.
| | - Harold Zakon
- Department of Integrative Biology, The University of Texas, Austin, TX, 78759, USA.
- Department of Neuroscience, The University of Texas, Austin, TX, 78759, USA.
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13
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McKenzie DJ, Belão TC, Killen SS, Rantin FT. To boldly gulp: standard metabolic rate and boldness have context-dependent influences on risk-taking to breathe air in a catfish. ACTA ACUST UNITED AC 2017; 218:3762-70. [PMID: 26632454 DOI: 10.1242/jeb.122903] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
The African sharptooth catfish Clarias gariepinus has bimodal respiration, it has a suprabranchial air-breathing organ alongside substantial gills. We used automated bimodal respirometry to reveal that undisturbed juvenile catfish (N=29) breathed air continuously in normoxia, with a marked diurnal cycle. Air breathing and routine metabolic rate (RMR) increased in darkness when, in the wild, this nocturnal predator forages. Aquatic hypoxia (20% air saturation) greatly increased overall reliance on air breathing. We investigated whether two measures of risk taking to breathe air, namely absolute rates of aerial O2 uptake (ṀO2,air) and the percentage of RMR obtained from air (%ṀO2,air), were influenced by individual standard metabolic rate (SMR) and boldness. In particular, whether any influence varied with resource availability (normoxia versus hypoxia) or relative fear of predation (day versus night). Individual SMR, derived from respirometry, had an overall positive influence on ṀO2,air across all contexts but a positive influence on %ṀO2,air only in hypoxia. Thus, a pervasive effect of SMR on air breathing became most acute in hypoxia, when individuals with higher O2 demand took proportionally more risks. Boldness was estimated as time required to resume air breathing after a fearful stimulus in daylight normoxia (Tres). Although Tres had no overall influence on ṀO2,air or %ṀO2,air, there was a negative relationship between Tres and %ṀO2,air in daylight, in normoxia and hypoxia. There were two Tres response groups, 'bold' phenotypes with Tres below 75 min (N=13) which, in daylight, breathed proportionally more air than 'shy' phenotypes with Tres above 115 min (N=16). Therefore, individual boldness influenced air breathing when fear of predation was high. Thus, individual energy demand and personality did not have parallel influences on the emergent tendency to take risks to obtain a resource; their influences varied in strength with context.
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Affiliation(s)
- David J McKenzie
- Department of Physiological Sciences, Federal University of São Carlos, 13565-905, São Carlos SP, Brazil UMR9190 Centre for Marine Biodiversity Exploitation and Conservation (Marbec), Place Eugène Bataillon, Université Montpellier, Montpellier cedex 5 34095, France
| | - Thiago C Belão
- Joint Graduate Program in Physiological Sciences, Federal University of São Carlos - UFSCar/São Paulo State University, UNESP Campus Araraquara, 14801-903, Araraquara SP, Brazil
| | - Shaun S Killen
- Institute of Biodiversity, Animal Health and Comparative Medicine, College of Medical, Veterinary and Life Sciences, University of Glasgow, Glasgow, G12 8QQ, UK
| | - F Tadeu Rantin
- Department of Physiological Sciences, Federal University of São Carlos, 13565-905, São Carlos SP, Brazil
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14
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The role of the autonomic nervous system in control of cardiac and air-breathing responses to sustained aerobic exercise in the African sharptooth catfish Clarias gariepinus. Comp Biochem Physiol A Mol Integr Physiol 2017; 203:273-280. [DOI: 10.1016/j.cbpa.2016.09.023] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2016] [Revised: 09/26/2016] [Accepted: 09/27/2016] [Indexed: 01/24/2023]
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15
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Drost HE, Lo M, Carmack EC, Farrell AP. Acclimation potential of Arctic cod (Boreogadus saida) from the rapidly warming Arctic Ocean. ACTA ACUST UNITED AC 2016; 219:3114-3125. [PMID: 27471275 DOI: 10.1242/jeb.140194] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Accepted: 07/25/2016] [Indexed: 01/07/2023]
Abstract
As a consequence of the growing concern about warming of the Arctic Ocean, this study quantified the thermal acclimation responses of Boreogadus saida, a key Arctic food web fish. Physiological rates for cardio-respiratory functions as well as critical maximum temperature (Tc,max) for loss of equilibrium (LOE) were measured. The transition temperatures for these events (LOE, the rate of oxygen uptake and maximum heart rate) during acute warming were used to gauge phenotypic plasticity after thermal acclimation from 0.5°C up to 6.5°C for 1 month (respiratory and Tc,max measurements) and 6 months (cardiac measurements). Tc,max increased significantly by 2.3°C from 14.9°C to 17.1°C with thermal acclimation, while the optimum temperature for absolute aerobic scope increased by 4.5°C over the same range of thermal acclimation. Warm acclimation reset the maximum heart rate to a statistically lower rate, but the first Arrhenius breakpoint temperature during acute warming was unchanged. The hierarchy of transition temperatures was quantified at three acclimation temperatures and was fitted inside a Fry temperature tolerance polygon to better define ecologically relevant thermal limits to performance of B. saida We conclude that B. saida can acclimate to 6.5°C water temperatures in the laboratory. However, at this acclimation temperature 50% of the fish were unable to recover from maximum swimming at the 8.5°C test temperature and their cardio-respiratory performance started to decline at water temperatures greater than 5.4°C. Such costs in performance may limit the ecological significance of B. saida acclimation potential.
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Affiliation(s)
- H E Drost
- Zoology Department, University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia, Canada V6T 1Z4
| | - M Lo
- Zoology Department, University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia, Canada V6T 1Z4
| | - E C Carmack
- Institute of Ocean Sciences, Fisheries and Oceans Canada, 9860 West Saanich Road, Sidney, British Columbia, Canada V8L 4B2
| | - A P Farrell
- Zoology Department, University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia, Canada V6T 1Z4 Faculty of Land and Food Systems, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
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16
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Norin T, Clark TD. Measurement and relevance of maximum metabolic rate in fishes. JOURNAL OF FISH BIOLOGY 2016; 88:122-51. [PMID: 26586591 DOI: 10.1111/jfb.12796] [Citation(s) in RCA: 238] [Impact Index Per Article: 26.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2014] [Accepted: 09/07/2015] [Indexed: 05/24/2023]
Abstract
Maximum (aerobic) metabolic rate (MMR) is defined here as the maximum rate of oxygen consumption (M˙O2max ) that a fish can achieve at a given temperature under any ecologically relevant circumstance. Different techniques exist for eliciting MMR of fishes, of which swim-flume respirometry (critical swimming speed tests and burst-swimming protocols) and exhaustive chases are the most common. Available data suggest that the most suitable method for eliciting MMR varies with species and ecotype, and depends on the propensity of the fish to sustain swimming for extended durations as well as its capacity to simultaneously exercise and digest food. MMR varies substantially (>10 fold) between species with different lifestyles (i.e. interspecific variation), and to a lesser extent (<three-fold) between individuals of the same species (i.e. intraspecific variation). MMR often changes allometrically with body size and is modulated by several environmental factors, including temperature and oxygen availability. Due to the significance of MMR in determining aerobic scope, interest in measuring this trait has spread across disciplines in attempts to predict effects of climate change on fish populations. Here, various techniques used to elicit and measure MMR in different fish species with contrasting lifestyles are outlined and the relevance of MMR to the ecology, fitness and climate change resilience of fishes is discussed.
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Affiliation(s)
- T Norin
- Department of Ocean Sciences, Memorial University of Newfoundland, Marine Lab Road, St. John's, NL, A1C 5S7, Canada
| | - T D Clark
- Australian Institute of Marine Science, PMB 3, Townsville MC, Qld, 4810, Australia
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17
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Lefevre S, Bayley M, McKenzie DJ. Measuring oxygen uptake in fishes with bimodal respiration. JOURNAL OF FISH BIOLOGY 2016; 88:206-231. [PMID: 26358224 DOI: 10.1111/jfb.12698] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2014] [Accepted: 03/17/2015] [Indexed: 06/05/2023]
Abstract
Respirometry is a robust method for measurement of oxygen uptake as a proxy for metabolic rate in fishes, and how species with bimodal respiration might meet their demands from water v. air has interested researchers for over a century. The challenges of measuring oxygen uptake from both water and air, preferably simultaneously, have been addressed in a variety of ways, which are briefly reviewed. These methods are not well-suited for the long-term measurements necessary to be certain of obtaining undisturbed patterns of respiratory partitioning, for example, to estimate traits such as standard metabolic rate. Such measurements require automated intermittent-closed respirometry that, for bimodal fishes, has only recently been developed. This paper describes two approaches in enough detail to be replicated by the interested researcher. These methods are for static respirometry. Measuring oxygen uptake by bimodal fishes during exercise poses specific challenges, which are described to aid the reader in designing experiments. The respiratory physiology and behaviour of air-breathing fishes is very complex and can easily be influenced by experimental conditions, and some general considerations are listed to facilitate the design of experiments. Air breathing is believed to have evolved in response to aquatic hypoxia and, probably, associated hypercapnia. The review ends by considering what realistic hypercapnia is, how hypercapnic tropical waters can become and how this might influence bimodal animals' gas exchange.
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Affiliation(s)
- S Lefevre
- Department of Biosciences, The Faculty of Mathematics and Natural Sciences, University of Oslo, P. O. Box 1066, 0316 Oslo, Norway
| | - M Bayley
- Zoophysiology, Aarhus University, Department of Bioscience, C. F. Møllers Allé 3, 8000 Aarhus C, Denmark
| | - D J McKenzie
- UMR 9190 Centre for Marine Biodiversity Exploitation and Conservation, Université Montpellier 2, Place Eugène Bataillon, 34095 Montpellier cedex 5, France
- Department of Physiological Sciences, Federal University of São Carlos, SP, Brazil
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18
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Lefevre S, Damsgaard C, Pascale DR, Nilsson GE, Stecyk JAW. Air breathing in the Arctic: influence of temperature, hypoxia, activity and restricted air access on respiratory physiology of the Alaska blackfish Dallia pectoralis. J Exp Biol 2014; 217:4387-98. [PMID: 25394628 PMCID: PMC4375840 DOI: 10.1242/jeb.105023] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2014] [Accepted: 10/28/2014] [Indexed: 01/21/2023]
Abstract
The Alaska blackfish (Dallia pectoralis) is an air-breathing fish native to Alaska and the Bering Sea islands, where it inhabits lakes that are ice-covered in the winter, but enters warm and hypoxic waters in the summer to forage and reproduce. To understand the respiratory physiology of this species under these conditions and the selective pressures that maintain the ability to breathe air, we acclimated fish to 5°C and 15°C and used respirometry to measure: standard oxygen uptake (Ṁ(O₂)) in normoxia (19.8 kPa P(O₂)) and hypoxia (2.5 kPa), with and without access to air; partitioning of standard Ṁ(O₂) in normoxia and hypoxia; maximum Ṁ(O₂) and partitioning after exercise; and critical oxygen tension (P(crit)). Additionally, the effects of temperature acclimation on haematocrit, haemoglobin oxygen affinity and gill morphology were assessed. Standard Ṁ(O₂) was higher, but air breathing was not increased, at 15°C or after exercise at both temperatures. Fish acclimated to 5°C or 15°C increased air breathing to compensate and fully maintain standard Ṁ(O₂) in hypoxia. Fish were able to maintain Ṁ(O₂) through aquatic respiration when air was denied in normoxia, but when air was denied in hypoxia, standard Ṁ(O₂) was reduced by ∼30-50%. P(crit) was relatively high (5 kPa) and there were no differences in P(crit), gill morphology, haematocrit or haemoglobin oxygen affinity at the two temperatures. Therefore, Alaska blackfish depends on air breathing in hypoxia and additional mechanisms must thus be utilised to survive hypoxic submergence during the winter, such as hypoxia-induced enhancement in the capacities for carrying and binding blood oxygen, behavioural avoidance of hypoxia and suppression of metabolic rate.
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Affiliation(s)
- Sjannie Lefevre
- Department of Biosciences, University of Oslo, Oslo 0316, Norway.
| | | | - Desirae R Pascale
- Department of Biological Sciences, University of Alaska Anchorage, AK 99508, USA
| | - Göran E Nilsson
- Department of Biosciences, University of Oslo, Oslo 0316, Norway
| | - Jonathan A W Stecyk
- Department of Biological Sciences, University of Alaska Anchorage, AK 99508, USA
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19
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Shartau RB, Brauner CJ. Acid-base and ion balance in fishes with bimodal respiration. JOURNAL OF FISH BIOLOGY 2014; 84:682-704. [PMID: 24502749 DOI: 10.1111/jfb.12310] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The evolution of air breathing during the Devonian provided early fishes with bimodal respiration with a stable O2 supply from air. This was, however, probably associated with challenges and trade-offs in terms of acid-base balance and ionoregulation due to reduced gill:water interaction and changes in gill morphology associated with air breathing. While many aspects of acid-base and ionoregulation in air-breathing fishes are similar to water breathers, the specific cellular and molecular mechanisms involved remain largely unstudied. In general, reduced ionic permeability appears to be an important adaptation in the few bimodal fishes investigated but it is not known if this is a general characteristic. The kidney appears to play an important role in minimizing ion loss to the freshwater environment in the few species investigated, and while ion uptake across the gut is probably important, it has been largely unexplored. In general, air breathing in facultative air-breathing fishes is associated with an acid-base disturbance, resulting in an increased partial pressure of arterial CO2 and a reduction in extracellular pH (pHE ); however, several fishes appear to be capable of tightly regulating tissue intracellular pH (pHI ), despite a large sustained reduction in pHE , a trait termed preferential pHI regulation. Further studies are needed to determine whether preferential pHI regulation is a general trait among bimodal fishes and if this confers reduced sensitivity to acid-base disturbances, including those induced by hypercarbia, exhaustive exercise and hypoxia or anoxia. Additionally, elucidating the cellular and molecular mechanisms may yield insight into whether preferential pHI regulation is a trait ultimately associated with the early evolution of air breathing in vertebrates.
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Affiliation(s)
- R B Shartau
- Department of Zoology, University of British Columbia, 6270 University Blvd., Vancouver, BC, V6T 1Z4 Canada
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20
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Lefevre S, Wang T, Jensen A, Cong NV, Huong DTT, Phuong NT, Bayley M. Air-breathing fishes in aquaculture. What can we learn from physiology? JOURNAL OF FISH BIOLOGY 2014; 84:705-731. [PMID: 24498927 DOI: 10.1111/jfb.12302] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
During the past decade, the culture of air-breathing fish species has increased dramatically and is now a significant global source of protein for human consumption. This development has generated a need for specific information on how to maximize growth and minimize the environmental effect of culture systems. Here, the existing data on metabolism in air-breathing fishes are reviewed, with the aim of shedding new light on the oxygen requirements of air-breathing fishes in aquaculture, reaching the conclusion that aquatic oxygenation is much more important than previously assumed. In addition, the possible effects on growth of the recurrent exposure to deep hypoxia and associated elevated concentrations of carbon dioxide, ammonia and nitrite, that occurs in the culture ponds used for air-breathing fishes, are discussed. Where data on air-breathing fishes are simply lacking, data for a few water-breathing species will be reviewed, to put the physiological effects into a growth perspective. It is argued that an understanding of air-breathing fishes' respiratory physiology, including metabolic rate, partitioning of oxygen uptake from air and water in facultative air breathers, the critical oxygen tension, can provide important input for the optimization of culture practices. Given the growing importance of air breathers in aquaculture production, there is an urgent need for further data on these issues.
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Affiliation(s)
- S Lefevre
- Zoophysiology section, Department of Bioscience, C. F. Møllers Allé 3, 8000 Aarhus C, Denmark
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21
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Lefevre S, Domenici P, McKenzie DJ. Swimming in air-breathing fishes. JOURNAL OF FISH BIOLOGY 2014; 84:661-681. [PMID: 24502687 DOI: 10.1111/jfb.12308] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/01/2013] [Accepted: 11/15/2013] [Indexed: 06/03/2023]
Abstract
Fishes with bimodal respiration differ in the extent of their reliance on air breathing to support aerobic metabolism, which is reflected in their lifestyles and ecologies. Many freshwater species undertake seasonal and reproductive migrations that presumably involve sustained aerobic exercise. In the six species studied to date, aerobic exercise in swim flumes stimulated air-breathing behaviour, and there is evidence that surfacing frequency and oxygen uptake from air show an exponential increase with increasing swimming speed. In some species, this was associated with an increase in the proportion of aerobic metabolism met by aerial respiration, while in others the proportion remained relatively constant. The ecological significance of anaerobic swimming activities, such as sprinting and fast-start manoeuvres during predator-prey interactions, has been little studied in air-breathing fishes. Some species practise air breathing during recovery itself, while others prefer to increase aquatic respiration, possibly to promote branchial ion exchange to restore acid-base balance, and to remain quiescent and avoid being visible to predators. Overall, the diversity of air-breathing fishes is reflected in their swimming physiology as well, and further research is needed to increase the understanding of the differences and the mechanisms through which air breathing is controlled and used during exercise.
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Affiliation(s)
- S Lefevre
- Department of Biosciences, The Faculty of Mathematics and Natural Sciences, University of Oslo, P. O. Box 1066, 0316 Oslo, Norway
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Lefevre S, Wang T, Huong DTT, Phuong NT, Bayley M. Partitioning of oxygen uptake and cost of surfacing during swimming in the air-breathing catfish Pangasianodon hypophthalmus. J Comp Physiol B 2012; 183:215-21. [DOI: 10.1007/s00360-012-0701-8] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2012] [Revised: 07/24/2012] [Accepted: 07/27/2012] [Indexed: 11/25/2022]
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