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Bukhari SSUH, Parkes RSV, Sneddon LU, McElligott AG. The behavior and welfare of neglected species: some examples from fish and mammals. PeerJ 2024; 12:e17149. [PMID: 38560452 PMCID: PMC10981888 DOI: 10.7717/peerj.17149] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Accepted: 03/01/2024] [Indexed: 04/04/2024] Open
Abstract
Animal welfare is the state of an animal's body and mind and the level to which its requirements are satisfied. Animal welfare is affected by human decisions and actions. Numerous decisions concerning animals are driven by human desires to enhance their own lives, and some of these decisions may be influenced by self-interest or a strong emphasis on economic factors. How to assess the welfare state of animals is a central issue in animal welfare science. Two critical questions can be used to address animal welfare: first, is the animal healthy, and second, does the animal have what it needs? Both of these questions can potentially be answered using the study of animal behavior. The development of behavioral methodologies is crucial for evaluating welfare in contexts where concern for animal welfare is often highest, such as on intensive modern farms and sites where working animals are used. Herein, we discuss animal welfare by focusing on some of its major concepts and explanations. Later, to illustrate key aspects of animal welfare, we chose to examine the information that is available for some 'neglected' livestock species, which are commercially important on a global basis and found in large numbers: buffaloes (Bubalus bubalis), camels (Camelus dromedarius), donkeys (Equus asinus), mules (Equus asinus × Equus caballus), and lumpfish (Cyclopterus lumpus). We chose these species because there are major ongoing concerns about their welfare, and more research is required to help solve the various problems. Overall, there are strong imbalances in terms of the species that are usually studied in terms of animal welfare research, and we call for greater attention to those that have traditionally been neglected.
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Affiliation(s)
- Syed S. U. H. Bukhari
- Department of Veterinary Clinical Sciences, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong, China
- Centre for Animal Health and Welfare, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong, China
| | - Rebecca S. V. Parkes
- Department of Veterinary Clinical Sciences, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong, China
- Centre for Animal Health and Welfare, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong, China
- Large Animal Medicine and Surgery Department, School of Veterinary Medicine, St. George’s University, True Blue, St. George’s, Grenada, West Indies
| | - Lynne U. Sneddon
- Department of Biological & Environmental Sciences, University of Gothenburg, Gothenburg, Sweden
| | - Alan G. McElligott
- Centre for Animal Health and Welfare, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong, China
- Department of Infectious Diseases and Public Health, Jockey Club College of Veterinary Medicine and Life Sciences, City University of Hong Kong, Kowloon, Hong Kong, China
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Staven FR, Gesto M, Iversen MH, Andersen P, Patel DM, Nordeide JT, Kristensen T. Cohabitation With Atlantic Salmon ( Salmo salar) Affects Brain Neuromodulators But Not Welfare Indicators in Lumpfish ( Cyclopterus lumpus). Front Physiol 2022; 13:781519. [PMID: 35309044 PMCID: PMC8924591 DOI: 10.3389/fphys.2022.781519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2021] [Accepted: 01/27/2022] [Indexed: 11/13/2022] Open
Abstract
Lumpfish are utilized to combat ectoparasitic epidemics in salmon farming. Research gaps on both cleaning behavior and client preferences in a natural environment, emphasizes the need to investigate the physiological impacts on lumpfish during cohabitation with piscivorous Atlantic salmon. Lumpfish (39.9 g, S.D ± 8.98) were arranged in duplicate tanks (n = 40 per treatment) and exposed to Live Atlantic salmon (245.7 g, S.D ± 25.05), salmon Olfaction or lifelike salmon Models for 6 weeks. Growth and health scores were measured every second week. In addition, the final sampling included measurements of neuromodulators, body color, and plasma cortisol. A stimulation and suppression test of the hypothalamic-pituitary-interrenal (HPI) axis was used for chronic stress assessment. Results showed that growth, health scores, and body color remained unaffected by treatments. Significant reductions in levels of brain dopamine and norepinephrine were observed in Live compared to Control. Plasma cortisol was low in all treatments, while the stimulation and suppression test of the HPI axis revealed no indications of chronic stress. This study presents novel findings on the impact on neuromodulators from Atlantic salmon interaction in the lumpfish brain. We argue that the downregulation of dopamine and norepinephrine indicate plastic adjustments to cohabitation with no negative effect on the species. This is in accordance with no observed deviations in welfare measurements, including growth, health scores, body color, and stress. We conclude that exposure to salmon or salmon cues did not impact the welfare of the species in our laboratory setup, and that neuromodulators are affected by heterospecific interaction.
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Affiliation(s)
- Fredrik R. Staven
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
- Department of Research and Development, Aqua Kompetanse AS, Flatanger, Norway
| | - Manuel Gesto
- Section for Aquaculture, Technical University of Denmark, Hirtshals, Denmark
| | - Martin H. Iversen
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Per Andersen
- Department of Research and Development, Aqua Kompetanse AS, Flatanger, Norway
| | - Deepti M. Patel
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Jarle T. Nordeide
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
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Fjelldal PG, Madaro A, Hvas M, Stien LH, Oppedal F, Fraser TW. Skeletal deformities in wild and farmed cleaner fish species used in Atlantic salmon Salmo salar aquaculture. JOURNAL OF FISH BIOLOGY 2021; 98:1049-1058. [PMID: 32243571 DOI: 10.1111/jfb.14337] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/29/2019] [Revised: 03/09/2020] [Accepted: 03/31/2020] [Indexed: 06/11/2023]
Abstract
As a first attempt to assess bone health in cleaner fish production, wild and cultured ballan wrasse Labrus bergylta and lumpfish Cyclopterus lumpus were examined by radiology. In C. lumpus, wild fish (57%) had more vertebra deformities (≥1 deformed vertebrae) than cultured fish (2-16%). One wild C. lumpus had lordosis and another was missing the tail fin. In L. bergylta, wild fish (11%) had fewer vertebra deformities than cultured individuals (78-91%). Among the cultured L. bergylta, 17-53% of the fish had severe vertebra deformities (≥6 deformed vertebrae) with two predominate sites of location, one between vertebra 4 and 10 (S1) in the trunk, and one between 19 and 26 (S2) in the tail. Fusions dominated S1, while compressions dominated S2. Although wild L. bergylta had a low vertebra deformity level, 83% had calluses and 14% had fractures in haemal/neural spines and/or ribs. The site-specific appearance and pathology of fracture and callus in wild L. bergylta suggests these are induced by chronic mechanical stress, and a possible pathogenesis for fish hyperostosis is presented based on this notion. In conclusion, good bone health was documented in cultured C. lumpus, but cultured L. bergylta suffered poor bone health. How this affects survival, growth, swimming abilities and welfare in cultured wrasse should be further investigated. SIGNIFICANCE STATEMENT: Skeletal deformities were studied in ballan wrasse and lumpfish of both wild and cultured origin for the first time to identify potential welfare issues when deploying them as cleaner fish in salmon sea cages. While cultured lumpfish showed good bone health, cultured wrasse had a high occurrence of vertebra deformities, which is expected to impact lice eating efficiency and animal welfare negatively. These deformities are most likely induced early in development.
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Affiliation(s)
| | | | - Malthe Hvas
- Matre Research Station, Institute of Marine Research, Matredal, Norway
| | - Lars Helge Stien
- Matre Research Station, Institute of Marine Research, Matredal, Norway
| | - Frode Oppedal
- Matre Research Station, Institute of Marine Research, Matredal, Norway
| | - Thomas Wk Fraser
- Matre Research Station, Institute of Marine Research, Matredal, Norway
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Herrmann B, Sistiaga M, Jørgensen T. Size-dependent escape risk of lumpfish (Cyclopterus lumpus) from salmonid farm nets. MARINE POLLUTION BULLETIN 2021; 162:111904. [PMID: 33321307 DOI: 10.1016/j.marpolbul.2020.111904] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Revised: 11/25/2020] [Accepted: 11/29/2020] [Indexed: 06/12/2023]
Abstract
In the last decade, the salmon aquaculture industry has considerably increased the use of lumpfish juveniles as cleaner fish. Potential escape of reared lumpfish into the wild may spread diseases or genetically contaminate wild stocks. The guidelines for minimum sizes of cleaner fish to use in aquaculture cages are currently based on simple mesh penetration tests. However, these guidelines do not consider the potential compressibility of fish or changes in mesh state due to factors such as sea conditions and maintenance operations. This study shows that the industry-recommended minimum stocking sizes for a given mesh size may result in escape risk and that ignoring fish compressibility and mesh state can lead to underestimation of the lumpfish sizes that are able to escape. Our results can be used to develop new guidelines that will contribute to reduced escape of lumpfish from salmonid farms and lessen the potential environmental consequences.
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Affiliation(s)
- Bent Herrmann
- SINTEF Ocean, Brattørkaia 17C, N-7010 Trondheim, Norway; The Arctic University of Norway, UiT, Breivika, N-9037 Tromsø, Norway; DTU Aqua, Technical University of Denmark, Hirtshals, Denmark.
| | - Manu Sistiaga
- Institute of Marine Research, Postbox 1870, Nordnes, N-5817 Bergen, Norway; Norwegian University of Science and Technology, Otto Nielsens veg 10, N-7491 Trondheim, Norway
| | - Terje Jørgensen
- Institute of Marine Research, Postbox 1870, Nordnes, N-5817 Bergen, Norway
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Liver colour scoring index, carotenoids and lipid content assessment as a proxy for lumpfish (Cyclopterus lumpus L.) health and welfare condition. Sci Rep 2020; 10:8927. [PMID: 32488000 PMCID: PMC7265535 DOI: 10.1038/s41598-020-65535-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2019] [Accepted: 05/06/2020] [Indexed: 11/16/2022] Open
Abstract
Ensuring lumpfish health and welfare in salmon farms is vital to reduce the high mortality rates reported and to guarantee a high delousing efficiency. Recent observations of farmed lumpfish livers have shown colours ranging from pale (colours 1 and 2), through bright orange (colours 3 and 4), to dark reddish-brown (colours 5 and 6), some of which may be related to welfare condition. To characterize the status of lumpfish deployed in four Faroese salmon farms, several welfare indicators were assessed: a weight-length relationship, scoring of external physical damage, and after dissection, stomach content and liver colour scoring. Liver samples were weighed, stored and analysed for lipid content, lipid classes, total pigments, fatty acid profile and histopathology to explain the differences between the mentioned liver colours. Bright orange livers, liver colours 3 and 4, were related to increased levels of carotenoid pigments rather than levels of lipids and appear to reflect good fish welfare. However, dark reddish-brown colours, liver colours 5 and 6, were associated with very low levels of triacyl glycerides in the liver, indicating use of lipid reserves and poor welfare condition. Histopathology confirmed that the dark reddish-brown livers, liver colours 5 and 6, formed a distinct group. Thus, liver colour was shown to be a good welfare indicator and should be monitored in farms.
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Staven FR, Nordeide JT, Imsland AK, Andersen P, Iversen NS, Kristensen T. Is Habituation Measurable in Lumpfish Cyclopterus lumpus When Used as Cleaner Fish in Atlantic Salmon Salmo salar Aquaculture? Front Vet Sci 2019; 6:227. [PMID: 31338371 PMCID: PMC6629887 DOI: 10.3389/fvets.2019.00227] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2019] [Accepted: 06/24/2019] [Indexed: 11/13/2022] Open
Abstract
To investigate how lumpfish interact in Atlantic salmon aquaculture, physiological stress responses and changes in behaviour were analysed in experienced and naive lumpfish. Experienced lumpfish (30.2 ± 7.93 g, mean ± SD) coexisted with a commercial scale production unit of Atlantic salmon (1258.5 ± 152.12 g) for 30 to 60 days, while naive lumpfish (38.2 ± 12.37 g) were kept with conspecifics only. Ten trials from each background were tested. For each trial, 10 lumpfish were tagged and transferred to a video monitored experimental tank (2 × 2 × 0.7 m). In each trial, swimming behaviour was mapped for all lumpfish every 60 s in 20 min, 10 min before, and 10 min after the introduction of four Atlantic salmon. Naive lumpfish expressed significantly increased burst swimming activity and maintained longer interspecific distance to Atlantic salmon in comparison with experienced fish. In addition, mean plasma cortisol levels were significantly elevated in naive fish after exposure to Atlantic salmon. We argue that naive lumpfish expressed innate physiological and behavioural stress responses during first encounter with Atlantic salmon, while reduced responses in experienced individuals indicated habituation. The effect from behavioural and physiological stress in newly deployed naive lumpfish-before and during habituation-should be taken account for when lumpfish are introduced in commercial sea cages to improve welfare for the species. In addition, we suggest that habituation could be applicable during the rearing phase to moderate the transition from a simple tank environment with conspecifics only to interspecies interaction with Atlantic salmon in sea cages.
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Affiliation(s)
- Fredrik R Staven
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway.,Aqua Kompetanse AS, Flatanger, Norway
| | - Jarle T Nordeide
- Faculty of Biosciences and Aquaculture, Nord University, Bodø, Norway
| | - Albert K Imsland
- Akvaplan-niva Iceland Office, Kópavogur, Iceland.,Department of Biological Sciences, University of Bergen, Bergen, Norway
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7
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Imsland AK, Hangstad TA, Jonassen TM, Stefansson SO, Nilsen TO, Hovgaard P, Elvegård TA, Lindberg KS, Mikalsen B, Urskog TC, Norberg B, Andersson E, Spetland F, Reynolds P. The use of photoperiods to provide year round spawning in lumpfish Cyclopterus lumpus. Comp Biochem Physiol A Mol Integr Physiol 2019; 228:62-70. [DOI: 10.1016/j.cbpa.2018.11.004] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2018] [Revised: 11/05/2018] [Accepted: 11/05/2018] [Indexed: 11/17/2022]
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8
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Whittaker BA, Consuegra S, Garcia de Leaniz C. Genetic and phenotypic differentiation of lumpfish ( Cyclopterus lumpus) across the North Atlantic: implications for conservation and aquaculture. PeerJ 2018; 6:e5974. [PMID: 30498640 PMCID: PMC6251346 DOI: 10.7717/peerj.5974] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2018] [Accepted: 10/19/2018] [Indexed: 11/20/2022] Open
Abstract
Demand for lumpfish (Cyclopterus lumpus) has increased exponentially over the last decade, both for their roe, which is used as a caviar substitute, and increasingly also as cleaner fish to control sea lice in salmon farming. The species is classified as Near Threatened by the IUCN and there are growing concerns that over-exploitation of wild stocks and translocation of hatchery-reared lumpfish may compromise the genetic diversity of native populations. We carried out a comparative analysis of genetic and phenotypic variation across the species' range to estimate the level of genetic and phenotypic differentiation, and determined patterns of gene flow at spatial scales relevant to management. We found five genetically distinct groups located in the West Atlantic (USA and Canada), Mid Atlantic (Iceland), East Atlantic (Faroe Islands, Ireland, Scotland, Norway and Denmark), English Channel (England) and Baltic Sea (Sweden). Significant phenotypic differences were also found, with Baltic lumpfish growing more slowly, attaining a higher condition factor and maturing at a smaller size than North Atlantic lumpfish. Estimates of effective population size were consistently low across the North East Atlantic (Iceland, Faroe Islands and Norway), the area where most wild lumpfish are fished for their roe, and also for the aquaculture industry. Our study suggests that some lumpfish populations are very small and have low genetic diversity, which makes them particularly vulnerable to over-exploitation and genetic introgression. To protect them we advocate curtailing fishing effort, closing the breeding cycle of the species in captivity to reduce dependence on wild stocks, restricting the translocation of genetically distinct populations, and limiting the risk of farm escapes.
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Affiliation(s)
- Benjamin Alexander Whittaker
- Department of Biosciences, Centre for Sustainable Aquatic Research, Swansea University, Swansea, Wales, United Kingdom
| | - Sofia Consuegra
- Department of Biosciences, Centre for Sustainable Aquatic Research, Swansea University, Swansea, Wales, United Kingdom
| | - Carlos Garcia de Leaniz
- Department of Biosciences, Centre for Sustainable Aquatic Research, Swansea University, Swansea, Wales, United Kingdom
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9
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Brooker AJ, Papadopoulou A, Gutierrez C, Rey S, Davie A, Migaud H. Sustainable production and use of cleaner fish for the biological control of sea lice: recent advances and current challenges. Vet Rec 2018; 183:383. [DOI: 10.1136/vr.104966] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2018] [Revised: 06/26/2018] [Accepted: 07/06/2018] [Indexed: 11/04/2022]
Affiliation(s)
- Adam J Brooker
- Institute of Aquaculture, University of Stirling; Stirling UK
| | | | | | - Sonia Rey
- Institute of Aquaculture, University of Stirling; Stirling UK
| | - Andrew Davie
- Institute of Aquaculture, University of Stirling; Stirling UK
| | - Herve Migaud
- Institute of Aquaculture, University of Stirling; Stirling UK
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10
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Imsland AKD, Hanssen A, Nytrø AV, Reynolds P, Jonassen TM, Hangstad TA, Elvegård TA, Urskog TC, Mikalsen B. It works! Lumpfish can significantly lower sea lice infestation in large-scale salmon farming. Biol Open 2018; 7:7/9/bio036301. [PMID: 30177547 PMCID: PMC6176945 DOI: 10.1242/bio.036301] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
To assess the efficacy of lumpfish grazing on attached sea lice on Atlantic salmon, six large-scale sea cages, (130 m circumference, 37,688 m3 volume) each stocked with approximately 200,000 salmon 0+ smolts, were stocked with a 4, 6 and 8% density (8000, 12,000 and 16,000, respectively) of lumpfish. The sea cages without lumpfish acted as controls. Sea lice infestation levels on the salmon were monitored weekly and bi-weekly from 6 October to 17 May the subsequent year. Mortality of the lumpfish rose with decreasing sea temperatures to around 0.8% week-1 and did not vary between the lumpfish groups. There were clear signs of lumpfish grazing on sea lice, with significantly lower average levels of chalimus, pre-adult and adult female Lepeophtheirus salmonis and Caligus elongatus sea lice per salmon. Lumpfish in the high density (8%) group reduced the mature female L. salmonis to levels equal to or lower than the counts recorded prior to the start of the study. Overall, the present results indicate that lumpfish are a suitable cold-water option for biological delousing of Atlantic salmon in large-scale production conditions.
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Affiliation(s)
- Albert Kjartan Dagbjartarson Imsland
- Akvaplan-niva Iceland Office, Akralind 4, 201 Kópavogur, Iceland .,Department of Biology, University of Bergen, High Technology Centre, 5020 Bergen, Norway
| | | | | | - Patrick Reynolds
- Gildeskål Forskningsstasjon (GIFAS) AS, Gildeskål, 8140 Inndyr, Norway
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Johannesen A, Joensen NE, Magnussen E. Shelters can negatively affect growth and welfare in lumpfish if feed is delivered continuously. PeerJ 2018; 6:e4837. [PMID: 29844984 PMCID: PMC5971831 DOI: 10.7717/peerj.4837] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2018] [Accepted: 05/04/2018] [Indexed: 11/20/2022] Open
Abstract
Due to the socioeconomic importance of salmon farming in the North Atlantic and the economic impact of sea lice in this industry, there is high demand for novel pest control methods. One such method is the use of cleaner fish to remove the lice from the salmon. A cleaner fish that has recently gained in popularity due to its ability to work in cold water, is the lumpfish (Cyclopterus lumpus). This fish varies in efficiency, but when mortality is low and cleaning optimal, the fish are successful in keeping parasite burdens low. However, there is some concern for the welfare of lumpfish in the industry, because mortality is often high. This is sometimes attributed to inadequate feeding and shelter. Here we compare growth, body condition, and fin health of fish reared for four weeks in a crossed treatment design crossing shelter availability (shelter vs none) and feed delivery method (manual meal time feeds and continuous automated feeding). In terms of weight gain, shelter availability interacted with feeding method, with fish that had access to shelters and were fed using automated feeders gaining less weight than other fish. Fin health was not affected, but body condition was lowered both by access to shelter and being fed continuously. The results indicate a need to carefully consider how feeding method and shelter use is combined, both in cages and during rearing on land.
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Affiliation(s)
- Asa Johannesen
- Nesvik Marine Centre, Fiskaaling, Hvalvik, Faroe Islands
| | - Nakita E Joensen
- Department of Science and Technology, University of the Faroe Islands, Tórshavn, Faroe Islands
| | - Eyðfinn Magnussen
- Department of Science and Technology, University of the Faroe Islands, Tórshavn, Faroe Islands
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12
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Dunkley K, Cable J, Perkins SE. The selective cleaning behaviour of juvenile blue-headed wrasse (Thalassoma bifasciatum) in the Caribbean. Behav Processes 2017; 147:5-12. [PMID: 29247694 DOI: 10.1016/j.beproc.2017.12.005] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2017] [Revised: 12/01/2017] [Accepted: 12/06/2017] [Indexed: 11/29/2022]
Abstract
Through the removal of parasites, dead skin and mucus from the bodies of visiting reef fish (clients), cleaner fish have a significant ecosystem function in the ecology of coral reefs. Cleaners gain nutrition from these interactions and through offering a 'service' are afforded protection from predators. Given these benefits, it is unclear why more fish do not engage in cleaning, and why part-time cleaning strategies exist. On coral reefs, dedicated species clean throughout their life, whereas some species are facultative, employing opportunistic and/or temporary cleaning strategies. Here, we investigate the cleaning behaviour of a facultative species to assess the relative importance of this interaction to the cleaner. Using a combination of focal and event sampling from a coral reef in Tobago, we show that cleaning is not an essential food source for facultative juvenile blue-headed wrasse (Thalassoma bifasciatum), as cleaning rate was unrelated to their foraging rate on the substrate. These wrasse displayed two cleaning strategies: stationary versus wandering cleaning, with cleaning frequency being highest for stationary cleaners. A specific cleaning location facilitated increased cleaning frequency, and wrasse cleaning rate decreased as cleaner or client abundance increased. We also compared juvenile blue-headed wrasse cleaning behaviour to a resident dedicated cleaner, the sharknose goby (Elacatinus evelynae), and showed that, in comparison, juvenile wrasse clean a narrower client range, predominately cleaning three species of gregarious free-ranging surgeonfish (Acanthurus spp.). The wrasse, however, frequently approached these clients without cleaning, which suggests that their selective cleaning strategy may be driven by the acquisition of a particular parasitic food source. Juvenile blue-headed wrasse are generalist foragers, and may thus be limited in their cleaning behaviour by their nutritional requirements, the availability of a suitable cleaning site, and fish density, which ultimately means that they do not adopt more dedicated cleaning roles within the reef community.
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Affiliation(s)
- Katie Dunkley
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK.
| | - Jo Cable
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK
| | - Sarah E Perkins
- School of Biosciences, Cardiff University, Sir Martin Evans Building, Museum Avenue, Cardiff, CF10 3AX, UK
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13
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Jonassen T, Hamadi M, Remø SC, Waagbø R. An epidemiological study of cataracts in wild and farmed lumpfish (Cyclopterus lumpus L.) and the relation to nutrition. JOURNAL OF FISH DISEASES 2017; 40:1903-1914. [PMID: 28661002 DOI: 10.1111/jfd.12664] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 05/02/2017] [Accepted: 05/02/2017] [Indexed: 06/07/2023]
Abstract
Twelve groups of farmed lumpfish and one of wild lumpfish were screened for cataract and sampled for fish muscle tissue, whole heart and both eye lenses to investigate possible relations between cataract and tissue free amino acid concentrations. Cataract prevalence ranged from 20% to 100%, with the highest average score of 7.3 (max 8) and incidences of severe cataract (>5) in all groups. Cataract could not be explained by suboptimal histidine concentrations in the feed. Neither muscle nor cardiac tissues had concentrations of free histidine compounds. The lumpfish lens contained N-acetylhistidine (NAH), of which low concentrations were strongly related to cataract severity. However, no correlation between lens NAH and cataract severity was found in the present sample set. Wild lumpfish had higher levels compared to farmed lumpfish, suggesting that the farmed lumpfish may have been deficient in histidine or have a higher utilization of NAH due to osmotic problems. Thus, cataract in farmed lumpfish may be related to primary or secondary disturbed nutrient metabolism or malnutrition, shown by the high levels of specific amino acids in different tissues, which may cause osmotic imbalance and cataract development. This nutritional or environmental-related welfare problem deserves further research.
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Affiliation(s)
- T Jonassen
- Akvaplan-niva, Framsenteret, Tromsø, Norway
| | - M Hamadi
- Aqua Kompetanse, Flatanger, Norway
| | - S C Remø
- NIFES (The National Institute of Nutrition and Seafood Research), Bergen, Norway
| | - R Waagbø
- NIFES (The National Institute of Nutrition and Seafood Research), Bergen, Norway
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