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Linsky JMJ, Dunlop RA, Noad MJ, McMichael LA. Blubber gene expression and cortisol concentrations reveal changing physiological stress in a Southern ocean sentinel species. MARINE ENVIRONMENTAL RESEARCH 2024; 199:106596. [PMID: 38905865 DOI: 10.1016/j.marenvres.2024.106596] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/27/2024] [Revised: 05/21/2024] [Accepted: 06/06/2024] [Indexed: 06/23/2024]
Abstract
The health of migratory eastern Australian humpback whales (Megaptera novaeangliae) can reflect the condition of their remote polar foraging environments. This study used gene expression (LEP, LEPR, ADIQ, AhR, TNF-α, HSP-70), blubber hormone concentrations (cortisol, testosterone), and photogrammetric body condition to assess this sentinel species during a period of unprecedented changes to anthropogenic activity and natural processes. The results revealed higher cortisol concentrations in 2020 compared to 2021, suggesting a decline in physiological stress between years. Additionally, metabolic transcripts LEPR, and AhR, which is also linked to xenobiotic metabolism, were upregulated during the 2020 southbound migration. These differences suggest that one or more environmental stressors were reduced between 2020 and 2021, with upregulated AhR possibly indicating a Southern Ocean pollutant declined between the years. This research confirms a Southern Ocean-wide decrease in whale stress during the study period and informs efforts to identify key stressors on Antarctic marine ecosystems.
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Affiliation(s)
- Jacob M J Linsky
- School of the Environment, The University of Queensland, St Lucia, Queensland, 4072, Australia.
| | - Rebecca A Dunlop
- School of the Environment, The University of Queensland, St Lucia, Queensland, 4072, Australia
| | - Michael J Noad
- School of Veterinary Science, The University of Queensland, Gatton, Queensland, 4343, Australia; Centre for Marine Science, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Lee A McMichael
- School of Veterinary Science, The University of Queensland, Gatton, Queensland, 4343, Australia
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2
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O'Mahony ÉN, Sremba AL, Keen EM, Robinson N, Dundas A, Steel D, Wray J, Baker CS, Gaggiotti OE. Collecting baleen whale blow samples by drone: A minimally intrusive tool for conservation genetics. Mol Ecol Resour 2024:e13957. [PMID: 38576153 DOI: 10.1111/1755-0998.13957] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2023] [Revised: 03/05/2024] [Accepted: 03/25/2024] [Indexed: 04/06/2024]
Abstract
In coastal British Columbia, Canada, marine megafauna such as humpback whales (Megaptera novaeangliae) and fin whales (Balaenoptera physalus velifera) have been subject to a history of exploitation and near extirpation. While their populations have been in recovery, significant threats are posed to these vulnerable species by proposed natural resource ventures in this region, in addition to the compounding effects of anthropogenic climate change. Genetic tools play a vital role in informing conservation efforts, but the associated collection of tissue biopsy samples can be challenging for the investigators and disruptive to the ongoing behaviour of the targeted whales. Here, we evaluate a minimally intrusive approach based on collecting exhaled breath condensate, or respiratory 'blow' samples, from baleen whales using an unoccupied aerial system (UAS), within Gitga'at First Nation territory for conservation genetics. Minimal behavioural responses to the sampling technique were observed, with no response detected 87% of the time (of 112 UAS deployments). DNA from whale blow (n = 88 samples) was extracted, and DNA profiles consisting of 10 nuclear microsatellite loci, sex identification and mitochondrial (mt) DNA haplotypes were constructed. An average of 7.5 microsatellite loci per individual were successfully genotyped. The success rates for mtDNA and sex assignment were 80% and 89% respectively. Thus, this minimally intrusive sampling method can be used to describe genetic diversity and generate genetic profiles for individual identification. The results of this research demonstrate the potential of UAS-collected whale blow for conservation genetics from a remote location.
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Affiliation(s)
- Éadin N O'Mahony
- Centre for Biological Diversity and Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, Fife, UK
- North Coast Cetacean Society, Alert Bay, British Columbia, Canada
| | - Angela L Sremba
- Marine Mammal Institute, Hatfield Marine Science Centre, Oregon State University, Newport, Oregon, USA
- Cooperative Institute for Marine Ecosystem Resources, Oregon State University, Newport, Oregon, USA
| | - Eric M Keen
- North Coast Cetacean Society, Alert Bay, British Columbia, Canada
- Sewanee: The University of the South, Sewanee, Tennessee, USA
| | - Nicole Robinson
- Gitga'at Oceans and Lands Department, Hartley Bay, British Columbia, Canada
| | - Archie Dundas
- Gitga'at Oceans and Lands Department, Hartley Bay, British Columbia, Canada
| | - Debbie Steel
- Marine Mammal Institute, Hatfield Marine Science Centre, Oregon State University, Newport, Oregon, USA
| | - Janie Wray
- North Coast Cetacean Society, Alert Bay, British Columbia, Canada
| | - C Scott Baker
- Marine Mammal Institute, Hatfield Marine Science Centre, Oregon State University, Newport, Oregon, USA
| | - Oscar E Gaggiotti
- Centre for Biological Diversity and Scottish Oceans Institute, School of Biology, University of St Andrews, St Andrews, Fife, UK
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Aoyagi C, Tanaka T, Haga N, Yanase T, Kodama S. Differentiation of human adipose tissue-derived mesenchymal stromal cells into steroidogenic cells by adenovirus-mediated overexpression of NR5A1 and implantation into adrenal insufficient mice. Cytotherapy 2023; 25:866-876. [PMID: 37149799 DOI: 10.1016/j.jcyt.2023.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Revised: 03/30/2023] [Accepted: 04/10/2023] [Indexed: 05/08/2023]
Abstract
BACKGROUND AIMS Cell therapy for adrenal insufficiency is a potential method for physiological glucocorticoid and mineralocorticoid replacement. We have previously shown that mouse mesenchymal stromal cells (MSCs) differentiated into steroidogenic cells by the viral vector-mediated overexpression of nuclear receptor subfamily 5 group A member 1 (NR5A1), an essential regulator of steroidogenesis, and their implantation extended the survival of bilateral adrenalectomized (bADX) mice. METHODS In this study, we examined the capability of NR5A1-induced steroidogenic cells prepared from human adipose tissue-derived MSCs (MSC [AT]) and the therapeutic effect of the implantation of human NR5A1-induced steroidogenic cells into immunodeficient bADX mice. RESULTS Human NR5A1-induced steroidogenic cells secreted adrenal and gonadal steroids and exhibited responsiveness to adrenocorticotropic hormone and angiotensin II in vitro. In vivo, the survival time of bADX mice implanted with NR5A1-induced steroidogenic cells was significantly prolonged compared with that of bADX mice implanted with control MSC (AT). Serum cortisol levels, which indicate hormone secretion from the graft, were detected in bADX mice implanted with steroidogenic cells. CONCLUSIONS This is the first report to demonstrate steroid replacement by the implantation of steroid-producing cells derived from human MSC (AT). These results indicate the potential of human MSC (AT) to be a source of steroid hormone-producing cells.
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Affiliation(s)
- Chikao Aoyagi
- Department of Regenerative Medicine and Transplantation, Faculty of Medicine, Fukuoka University, Fukuoka, Japan; Department of Urology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | - Tomoko Tanaka
- Department of Regenerative Medicine and Transplantation, Faculty of Medicine, Fukuoka University, Fukuoka, Japan.
| | - Nobuhiro Haga
- Department of Urology, Faculty of Medicine, Fukuoka University, Fukuoka, Japan
| | | | - Shohta Kodama
- Department of Regenerative Medicine and Transplantation, Faculty of Medicine, Fukuoka University, Fukuoka, Japan.
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Wong CH, Tsai MA, Ko FC, Wang JH, Xue YJ, Yang WC. Skin Cortisol and Acoustic Activity: Potential Tools to Evaluate Stress and Welfare in Captive Cetaceans. Animals (Basel) 2023; 13:ani13091521. [PMID: 37174558 PMCID: PMC10177183 DOI: 10.3390/ani13091521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 04/05/2023] [Accepted: 04/26/2023] [Indexed: 05/15/2023] Open
Abstract
As people's focus broadens from animals on farms to zoos and aquaria, the field of welfare science and the public's concern for animal welfare continue to grow. In captive animals, stress and its causes are topics of interest in welfare issues, and the identification of an objective method that can be used to assess animals' stress as a physiological state is essential. Both behavioral and physiological parameters can be used as indicators in order to assess animal stress quantitatively. To validate this approach, acoustic activity and the sloughed scrape skin cortisol concentration were used to evaluate the animal welfare of captive beluga whales (Delphinapterus leucas). The acoustic activity (5 min at 10:00 am) of three captive D. leucas was routinely recorded by a transducer and analyzed using audio editing software. The calls were separated into three main categories: whistles, pulses, and combo calls. The sloughed scrape skin samples were collected non-invasively once a week from all three animals' fluke and/or flipper. Cortisol was extracted using a modified skin steroid extraction technique, and detected via commercially available enzyme immunoassays. The results showed that the cortisol concentration increased by varying levels when the whales encountered the same event. In addition, the number and distribution of the calls changed along with the events. This indicated that the changes in the cortisol concentration and acoustic behavior may have reflected the fluctuations in the environment and body condition. Therefore, the scrape cortisol measurement and acoustic recordings could be used to monitor stress levels in captive beluga whales. We recommend that aquaria consider incorporating skin scrape cortisol and acoustic activity monitoring into their standards for animal welfare.
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Affiliation(s)
- Chung-Hei Wong
- School of Veterinary Medicine, National Taiwan University, Taipei 106, Taiwan
| | - Ming-An Tsai
- Collage of Veterinary Medicine, National Pingtung University of Science and Technology, Pingtung 912, Taiwan
- National Museum of Marine Biology and Aquarium, Pingtung 944, Taiwan
| | - Fung-Chi Ko
- National Museum of Marine Biology and Aquarium, Pingtung 944, Taiwan
- Institute of Marine Biology, National Dong-Hwa University, Pingtung 944, Taiwan
| | - Jiann-Hsiung Wang
- College of Veterinary Medicine, National Chiayi University, Chiayi 600, Taiwan
| | - Yi-Jing Xue
- College of Veterinary Medicine, National Chiayi University, Chiayi 600, Taiwan
| | - Wei-Cheng Yang
- School of Veterinary Medicine, National Taiwan University, Taipei 106, Taiwan
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Béland K, Lair S, Guay M, Juette T, Bédard C, Black SR, Marcoux M, Watt CA, Hussey NE, Desmarchelier M. VALIDATION OF ENZYME-LINKED IMMUNOSORBENT ASSAY TECHNIQUES TO MEASURE SERUM DEHYDROEPIANDROSTERONE (DHEA) AND DHEA-S IN NARWHALS ( MONODON MONOCEROS). J Zoo Wildl Med 2023; 54:119-130. [PMID: 36971636 DOI: 10.1638/2022-0049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 11/23/2022] [Indexed: 03/29/2023] Open
Abstract
Narwhals (Monodon monoceros) are increasingly exposed to anthropogenic disturbances that may increase their stress levels with unknown consequences for the overall population dynamics. The validation and measurement of chronic stress biomarkers could contribute toward improved understanding and conservation efforts for this species. Dehydroepiandrosterone (DHEA) and its sulfated metabolite DHEA-S are collectively referred to as DHEA(S). Serum DHEA(S) concentrations combined in ratios with cortisol [cortisol/DHEA(S)] have been shown to be promising indicators of chronic stress in humans, domestic animals, and wildlife. During field tagging in 2017 and 2018 in Baffin Bay, Nunavut, Canada, 14 wild narwhals were sampled at the beginning and end of the capture-tagging procedures. Serum DHEA(S) were measured with commercially available competitive enzyme-linked immunosorbent assays (ELISA) developed for humans. A partial validation of the ELISA assays was performed by the determination of the intra-assay coefficient of variation, confirmation of the DHEA(S) dilutional linearity, and the calculation of the percentage of recovery. Mean values (nanograms per milliliter ± standard error of the mean) of narwhal serum cortisol, DHEA(S), and cortisol/DHEA(S) ratios, at the beginning and at the end of handling, respectively, are reported (cortisol = 30.74 ± 4.87 and 41.83 ± 4.83; DHEA = 1.01 ± 0.52 and 0.99 ± 0.50; DHEA-S = 8.72 ± 1.68 and 7.70 ± 1.02; cortisol/DHEA = 75.43 ± 24.35 and 84.41 ± 11.76, and cortisol/DHEA-S = 4.16 ± 1.07 and 6.14 ± 1.00). Serum cortisol and cortisol/DHEA-S were statistically higher at the end of the capture (P= 0.024 and P= 0.035, respectively). Moreover, serum cortisol at the end of handling was positively correlated to total body length (P = 0.042) and tended to be higher in males (P = 0.086). These assays proved easy to perform, rapid, and suitable for measuring serum DHEA(S) of narwhals and that calculated cortisol/DHEA(S) are potential biomarkers for chronic stress in narwhals and possibly other cetaceans.
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Affiliation(s)
- Karine Béland
- Faculté de médecine vétérinaire, Université de Montréal, St. Hyacinthe, QC J2S 7C6, Canada
| | - Stéphane Lair
- Faculté de médecine vétérinaire, Université de Montréal, St. Hyacinthe, QC J2S 7C6, Canada
| | - Mario Guay
- Faculté de médecine vétérinaire, Université de Montréal, St. Hyacinthe, QC J2S 7C6, Canada
| | - Tristan Juette
- Faculté de médecine vétérinaire, Université de Montréal, St. Hyacinthe, QC J2S 7C6, Canada
| | - Christian Bédard
- Faculté de médecine vétérinaire, Université de Montréal, St. Hyacinthe, QC J2S 7C6, Canada
| | - Sandra R Black
- Faculty of Veterinary Medicine, University of Calgary, Calgary, AB T2N 4Z6, Canada
| | - Marianne Marcoux
- Freshwater Institute, Fisheries and Oceans Canada, Winnipeg, MB R3T 2N6, Canada
| | - Cortney A Watt
- Freshwater Institute, Fisheries and Oceans Canada, Winnipeg, MB R3T 2N6, Canada
| | - Nigel E Hussey
- Department of Integrative Biology, University of Windsor, Windsor, ON N9B 3P4, Canada
| | - Marion Desmarchelier
- Faculté de médecine vétérinaire, Université de Montréal, St. Hyacinthe, QC J2S 7C6, Canada,
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Richard JT, Schultz K, Goertz CEC, Hobbs RC, Romano TA, Sartini BL. Evaluating beluga ( Delphinapterus leucas) blow samples as a potential diagnostic for immune function gene expression within the respiratory system. CONSERVATION PHYSIOLOGY 2022; 10:coac045. [PMID: 35795014 PMCID: PMC9252111 DOI: 10.1093/conphys/coac045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/19/2021] [Revised: 05/06/2022] [Accepted: 06/22/2022] [Indexed: 06/15/2023]
Abstract
Evaluating respiratory health is important in the management of cetaceans, which are vulnerable to respiratory diseases. Quantifying the expression of genes related to immune function within the respiratory tract could be a valuable tool for directly assessing respiratory health. Blow (exhale) samples allow DNA analysis, and we hypothesized that RNA could also be isolated from blow samples for gene expression studies of immune function. We evaluated the potential to extract RNA from beluga blow samples and tested whether transcripts associated with immune function could be detected with endpoint polymerase chain reaction. A total of 54 blow samples were collected from clinically healthy aquarium belugas (n = 3), and 15 were collected from wild belugas temporarily restrained for health assessment in Bristol Bay, Alaska (n = 9). Although RNA yield varied widely (range, 0-265.2 ng; mean = 85.8; SD = 71.3), measurable RNA was extracted from 97% of the samples. Extracted RNA was assessed in 1-6 PCR reactions targeting housekeeping genes (Rpl8, Gapdh or ActB) or genes associated with immune function (TNFα, IL-12p40 or Cox-2). Fifty of the aquarium samples (93%) amplified at least one transcript; overall PCR success for housekeeping genes (96/110, 87%) and genes associated with immune function (90/104, 87%) were similarly high. Both RNA yield and overall PCR success (27%) were lower for wild beluga samples, which is most likely due to the reduced forcefulness of the exhale when compared with trained or free-swimming belugas. Overall, the high detection rate with PCR suggests measuring gene expression in blow samples could provide diagnostic information about immune responses within the respiratory tract. While further study is required to determine if quantitative gene expression data from blow samples is associated with disease states, the non-invasive nature of this approach may prove valuable for belugas, which face increasing anthropogenic disturbances.
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Affiliation(s)
- Justin T Richard
- Corresponding author: Department of Fisheries, Animal and Veterinary Science, University of Rhode Island, Kingston, RI 02881, USA.
| | - Krystle Schultz
- Department of Fisheries, Animal and Veterinary Science, University of Rhode Island, 9 E Alumni Drive, Kingston, RI 02881, USA
| | | | - Roderick C Hobbs
- Retired from Marine Mammal Laboratory, Alaska Fisheries Science Center, 7600 Sand Point Way NE, F/AKC3, Seattle, WA 98115-6349, USA
| | - Tracy A Romano
- Mystic Aquarium, a Division of Sea Research Foundation, 55 Coogan Blvd, Mystic, CT 06355, USA
| | - Becky L Sartini
- Department of Fisheries, Animal and Veterinary Science, University of Rhode Island, 9 E Alumni Drive, Kingston, RI 02881, USA
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A Review of Non-Invasive Sampling in Wildlife Disease and Health Research: What’s New? Animals (Basel) 2022; 12:ani12131719. [PMID: 35804619 PMCID: PMC9265025 DOI: 10.3390/ani12131719] [Citation(s) in RCA: 17] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 06/28/2022] [Accepted: 06/29/2022] [Indexed: 12/14/2022] Open
Abstract
Simple Summary The interest in wildlife research has increased in the last decades as more scientists work within a One Health framework that regards human, livestock and wildlife health as connected entities. To minimise the impact of research on wildlife, collecting samples with as little disturbance of the animals as possible is important. In our review, we assess the use of so-called non-invasive sampling and summarise which samples can be used successfully when carrying out research on wildlife diseases and health status. Our results show that interest in minimally invasive sampling has steadily increased since the 2010s. Topics able to employ these methods include disease research, but also stress and other hormone assessments, pollution studies, and dietary studies. At the moment, such methods are mainly used to collect samples from land mammals, however, they can also be used in a wide range of other animals. Ever more capable analytical methods will allow for an even wider use of such “animal-friendly” sampling methods. Abstract In the last decades, wildlife diseases and the health status of animal populations have gained increasing attention from the scientific community as part of a One Health framework. Furthermore, the need for non-invasive sampling methods with a minimal impact on wildlife has become paramount in complying with modern ethical standards and regulations, and to collect high-quality and unbiased data. We analysed the publication trends on non-invasive sampling in wildlife health and disease research and offer a comprehensive review on the different samples that can be collected non-invasively. We retrieved 272 articles spanning from 1998 to 2021, with a rapid increase in number from 2010. Thirty-nine percent of the papers were focussed on diseases, 58% on other health-related topics, and 3% on both. Stress and other physiological parameters were the most addressed research topics, followed by viruses, helminths, and bacterial infections. Terrestrial mammals accounted for 75% of all publications, and faeces were the most widely used sample. Our review of the sampling materials and collection methods highlights that, although the use of some types of samples for specific applications is now consolidated, others are perhaps still underutilised and new technologies may offer future opportunities for an even wider use of non-invasively collected samples.
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Rickert D, Simon R, von Fersen L, Baumgartner K, Bertsch T, Kirschbaum C, Erhard M. Saliva and Blood Cortisol Measurement in Bottlenose Dolphins ( Tursiops truncatus): Methodology, Application, and Limitations. Animals (Basel) 2021; 12:ani12010022. [PMID: 35011127 PMCID: PMC8749515 DOI: 10.3390/ani12010022] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 12/16/2021] [Accepted: 12/18/2021] [Indexed: 12/17/2022] Open
Abstract
Simple Summary Animal welfare assessments in zoological facilities are becoming increasingly important. Two main assessment tools are behavioral observations and stress hormone measurements. At our facility (Nuremberg Zoo), cortisol levels are routinely determined every time blood samples are taken. We can show that the blood cortisol content of bottlenose dolphins depends on the way in which sampling is performed. Cortisol levels are significantly lower when blood samples are taken during voluntary medical training compared to when dolphins are sampled on a lifting platform, which results in higher cortisol levels. For a subset of the blood cortisol data, we simultaneously sampled saliva cortisol. However, we did not find any correlation between saliva cortisol and blood cortisol values. We also tested whether saliva samples are contaminated by fodder fish or diluted by pool water, finding that some fish and squid species exhibit high cortisol values. Consequently, dolphin saliva is highly contaminated directly after feeding, and increased values can be measured up to 4 min after feeding. We recommend being very careful when sampling saliva, and interpreting saliva cortisol values with caution. Abstract A central task of zoos and aquaria is the frequent and accurate assessment of their animals’ welfare. Recently, important steps have been made, such as the introduction of animal welfare evaluation tools and welfare decision trees. To determine animal welfare, it is not only important to collect life history data, such as longevity and reproductive success, but also for experienced observers or caretakers to conduct behavioral observations on a regular basis to assess animals’ emotional state. To physiologically validate welfare observations, glucocorticoid levels are usually assessed, as they are a common indicator of stress. While, for many animals, these levels can be easily determined via fecal or hair samples, for cetaceans, the levels are usually determined via blood samples. As blood samples cannot be taken very frequently and the process may cause stress to the animals (if the samples are not taken following medical training), other techniques, such as the measurement of health biomarkers (especially cortisol, which can be measured in saliva), have become the focus of cetacean stress research. However, there are two problems associated with saliva measurements in cetaceans: saliva might either be diluted with pool water or be contaminated by fodder fish, as frozen fish usually contains high levels of cortisol. In our study, we investigated how saliva cortisol levels are connected to blood cortisol levels and how saliva cortisol can be influenced by fodder fish. We examined saliva and blood samples in eleven bottlenose dolphins (Tursiops truncatus) kept in an outdoor and indoor facility in Germany. Furthermore, we assessed the cortisol levels of different kinds of fodder fish. Our data show that, although saliva cortisol values are elevated under stress and arousal, they seem not to be correlated with blood cortisol values. We also show that, after feeding, saliva cortisol values are increased up to 100-fold. Our results suggest that saliva cortisol measurements in dolphins have to be conducted and considered with care, as they can easily be contaminated. Moreover, it is important to use the right laboratory method in order to specifically detect cortisol; in our study, we conducted reliable tests, using LC-MS/MS.
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Affiliation(s)
- Daniela Rickert
- Nuremberg Zoo, 90480 Nuremberg, Germany; (D.R.); (L.v.F.); (K.B.)
- Department of Veterinary Sciences, Faculty of Veterinary Medicine, Institute of Animal Welfare, Ethology and Animal Hygiene, Ludwig-Maximilians-University, 80637 Munich, Germany;
| | - Ralph Simon
- Nuremberg Zoo, 90480 Nuremberg, Germany; (D.R.); (L.v.F.); (K.B.)
- Correspondence:
| | | | | | - Thomas Bertsch
- Institute of Clinical Chemistry, Laboratory Medicine and Transfusion Medicine, Nuremberg General Hospital, Paracelsus Medical University, 90419 Nuremberg, Germany;
| | - Clemens Kirschbaum
- Department of Psychology, Faculty of Science, Institute of General Psychology, Biopsychology and Methods of Psychology, Technische Universität Dresden, 01069 Dresden, Germany;
| | - Michael Erhard
- Department of Veterinary Sciences, Faculty of Veterinary Medicine, Institute of Animal Welfare, Ethology and Animal Hygiene, Ludwig-Maximilians-University, 80637 Munich, Germany;
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Houser DS, Champagne CD, Wasser SK, Booth RK, Romano T, Crocker DE. Influence of season, age, sex, and time of day on the endocrine profile of the common bottlenose dolphin (Tursiops truncatus). Gen Comp Endocrinol 2021; 313:113889. [PMID: 34425086 DOI: 10.1016/j.ygcen.2021.113889] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 08/03/2021] [Accepted: 08/18/2021] [Indexed: 01/15/2023]
Abstract
Understanding baseline hormone levels, the magnitude of intra-individual variability, and their variation as a function of life history is difficult in toothed whales (e.g. dolphins and porpoises) because of the effects of capture stress. To determine the endocrine profile of the common bottlenose dolphin (Tursiops truncatus) as a function of season, time of day (TOD), age, sex, and reproductive status, blood corticosteroids, thyroid hormones, and catecholamines were repeatedly measured in a managed-care population exposed to ambient light and water temperatures of San Diego Bay. Additionally, fecal hormone metabolites were assessed for cortisol, aldosterone, and triiodothyronine. Samples were collected at two to four-week intervals over a period of two years, and multiple times within a day at monthly intervals over a year. Samples were collected through the voluntary participation of the dolphins in the blood draws and fecal collections in order to avoid the effects of handling stress. All serum hormones except aldosterone significantly varied with season and all serum hormones except total thyroxine significantly varied as a function of TOD. Fecal glucocorticoid metabolites significantly correlated with circulating cortisol levels, and there was a significant seasonal effect on triiodothyronine fecal metabolites. Strong seasonal effects demonstrated complex interactions with age and sex suggesting that contextual information is critical to interpreting differences in endocrine profiles. Strong circadian patterns further suggest that sampling design is important to the interpretation of blood or fecal collections, particularly since diurnal changes in some serum hormone levels are similar to the magnitude of seasonal differences. Despite potential impacts of feeding schedules on diurnal patterns, managed care populations can provide important insights into seasonal and age-related endocrine changes in toothed whales.
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Affiliation(s)
- D S Houser
- National Marine Mammal Foundation, 2240 Shelter Island Drive, Suite 200, San Diego, CA 92106, USA.
| | - C D Champagne
- National Marine Mammal Foundation, 2240 Shelter Island Drive, Suite 200, San Diego, CA 92106, USA
| | - S K Wasser
- Center for Conservation Biology, Box 351800, University of Washington, Seattle, WA 98195, USA
| | - R K Booth
- Center for Conservation Biology, Box 351800, University of Washington, Seattle, WA 98195, USA
| | - T Romano
- Mystic Aquarium, 55 Coogan Blvd, Mystic, CT 06355, USA
| | - D E Crocker
- Department of Biology, Sonoma State University, 1801 E. Cotati Ave, Rohnert Park, CA 94928, USA
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10
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Of Whales and Genes: Unraveling the Physiological Response to Stressors in Belugas (Delphinapterus leucas) at the Molecular Level. JOURNAL OF ZOOLOGICAL AND BOTANICAL GARDENS 2021. [DOI: 10.3390/jzbg2040040] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
Marine mammals, now more than ever, are exposed to environmental and anthropogenic stressors. A better understanding of stress physiology in marine mammals is warranted in order to assist in conservation efforts. This study screened gene expression profiles (cytokines, stress-response markers) in blood samples collected opportunistically under controlled conditions from aquarium belugas during transport and introduction to a novel environment (T/NEnv), participation in out-of-water examinations (OWE) and from wild belugas during live capture–release health assessments (WLCR). Quantitative-PCR was used to measure gene expression involved in physiological and immune responses at different time scales. Linear mixed models with repeated measures and pairwise comparisons were used for analysis. Overall, a generalized down-regulation of relative gene expression when compared to samples collected under behavioral control from aquarium whales or to pre-assessment samples of wild whales was observed, with genes IFNγ, IL2, TGFβ and Nr3c1 displaying the largest significant (p < 0.05) changes. Significant (p < 0.05) negative associations of inflammatory gene expression with norepinephrine suggest inhibitory effects of catecholamines on the inflammatory response. Overall, this study contributes to our understanding of the physiological response to stressors at the molecular level in belugas, and the genes suggested here can further be utilized as additional tools in beluga health assessments and monitoring.
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Is Harbor Porpoise ( Phocoena phocoena) Exhaled Breath Sampling Suitable for Hormonal Assessments? Animals (Basel) 2021; 11:ani11030907. [PMID: 33810041 PMCID: PMC8004923 DOI: 10.3390/ani11030907] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2021] [Revised: 03/05/2021] [Accepted: 03/15/2021] [Indexed: 12/19/2022] Open
Abstract
Simple Summary The progress of animal welfare in wildlife conservation and research calls for more non-invasive sampling techniques. In cetaceans, exhaled breath condensate (blow)—a mixture of cells, mucus and fluids expelled through the force of a whale’s exhale—is a unique sampling matrix for hormones, bacteria and genetic material, among others. Especially the detection of steroid hormones, such as cortisol, is being investigated as stress indicators in several species. As the only native cetacean in Germany, harbor porpoises (Phocoena phocoena) are of special conservation concern and research interest. So far, strandings and live captures have been the only method to obtain samples from free-ranging individuals, and novel, non-invasive monitoring methods are desirable for this small cetacean species. Hence, three different blow collection devices were tested on harbor porpoises. All samples were analyzed for cortisol using a commercially available immunosorbent assay. The most suitable protocol for sampling, storage and processing is using a sterile 50 mL centrifuge tube. This pilot study shows that cortisol can be detected in the exhale of harbor porpoises, thus paving the way for future studies and most likely successful non-invasive small cetacean health monitoring through blow. Abstract Over the last decades, exhaled breath sampling has been established for laboratory analysis in various cetacean species. Due to their small size, the usability of respiratory vapor for hormone assessments was questionable in harbor porpoises (Phocoena phocoena). This pilot study compared three different blow collection devices for their suitability in the field and during laboratory processing: a sterile petri dish covered by a Nitex membrane, as well as sterile 50 mL centrifuge tubes with or without manganese(II) chloride as a stabilizer. Collected exhales varied between three, five or ten, depending on feasibility. Hormones were extracted through an ether mix, followed by centrifugal evaporation and cortisol analysis using an immunoassay. Although close to the lower end of the assay’s dynamic range, the ELISA produced results (n = 110, 0.102–0.937 ng/mL). Hence, a simple 50 mL centrifuge tube was determined as the best suited blow collection device, while three consecutive exhales proved sufficient to yield results. These findings are promising regarding the suitability of exhaled breath as a matrix for future endocrine and immune system-related studies in harbor porpoises. If further advanced, blow sampling can become an important, non-invasive tool for studying and monitoring health, stress levels and diseases in harbor porpoises.
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Hudson JM, Matthews CJD, Watt CA. Detection of steroid and thyroid hormones in mammalian teeth. CONSERVATION PHYSIOLOGY 2021; 9:coab087. [PMID: 36439380 PMCID: PMC8633673 DOI: 10.1093/conphys/coab087] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 08/30/2021] [Accepted: 10/27/2021] [Indexed: 05/21/2023]
Abstract
Endocrine tools can provide an avenue to better understand mammalian life histories and predict how individuals and populations may respond to environmental stressors; however, few options exist for studying long-term endocrine patterns in individual marine mammals. Here, we (i) determined whether hormones could be measured in teeth from four marine mammal species: narwhal (Monodon monoceros), beluga (Delphinapterus leucas), killer whale (Orcinus orca) and Atlantic walrus (Odobenus rosmarus rosmarus); (ii) validated commercially available enzyme immunoassay kits for use with tooth extracts; and (iii) conducted biological validations for each species to determine whether reproductive hormone concentrations in teeth correlated with age of sexual maturity. Tooth extracts from all species had measurable concentrations of progesterone, testosterone, 17β-estradiol, corticosterone, aldosterone and triiodothyronine (T3); however, cortisol was undetectable. Parallelism between the binding curves of assay kit standards and serially diluted pools of tooth extract for each species was observed for all measurable hormones. Slopes of accuracy tests ranged from 0.750 to 1.116, with r2 values ranging from 0.977 to 1.000, indicating acceptable accuracy. Biological validations were inconsistent with predictions for each species, with the exception of female killer whales (n = 2), which assumed higher progesterone and testosterone concentrations in mature individuals than immature individuals. Instead, we observed a decline in progesterone and testosterone concentrations from infancy through adulthood in narwhal (n = 1) and walruses (n = 2) and higher reproductive hormone concentrations in immature individuals than mature individuals in belugas (n = 8 and 10, respectively) and male killer whales (n = 1 and 2, respectively). While unexpected, this pattern has been observed in other taxa; however, further analytical and biological validations are necessary before this technique can be used to assess individual mammalian endocrine patterns.
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Affiliation(s)
- Justine M Hudson
- Corresponding author: Fisheries and Oceans Canada, Winnipeg, R3T 2N6, Canada. Tel: 1 (204) 984-0550.
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A Comparison of the Acute Effects of Different Forms of Yoga on Physiological and Psychological Stress: A Pilot Study. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17176090. [PMID: 32825677 PMCID: PMC7503485 DOI: 10.3390/ijerph17176090] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2020] [Accepted: 08/18/2020] [Indexed: 11/17/2022]
Abstract
Yoga is a frequently recommended stress management strategy; however, the acute stress response to varying types of yoga are not fully clear. Thus, the purpose of this study was to compare the acute effects of meditative and power yoga on indices of physiological and psychological stress. In a crossover counterbalanced design, physically active females (n = 13; age = 20.8 yrs ± 0.8, height = 164.5 cm ± 6.1, body mass = 65.0 kg ± 13.8) who did not regularly participate in yoga or mindful training enrolled in this study. Participants completed two visits each, with a standardized instructional-video 30-min yoga session with either A) meditative (Hatha style) yoga or B) power (Vinyasa style) yoga. Prior to and immediately after each yoga bout, psychological stress was assessed using the State–Trait Anxiety Inventory (STAI) questionnaire, and salivary cortisol samples were obtained to measure indices of physiological stress. State anxiety scores were significantly lower following meditative yoga (p = 0.047) but were not different following power yoga (p = 0.625). Salivary cortisol levels were significantly lower following meditative yoga (p = 0.020) but not following power yoga (p = 0.242). Results indicate that acute engagement in meditative yoga decreases markers of psychological and physiological stress, while power yoga does not impart a significant stress-relieving benefit. Findings indicate that differing types of yoga may have various stress-relieving capabilities and should be considered by individuals seeking anxiolytic benefits.
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Hou Z, Peng Z, Ning Y, Liu D, Chai H, Jiang G. An initial coprological survey of parasitic fauna in the wild Amur leopard (Panthera pardus orientalis). Integr Zool 2020; 15:375-384. [PMID: 32302039 DOI: 10.1111/1749-4877.12435] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
The Amur leopard, one of nine recently recognized subspecies of leopard, is still the most threatened by a stochastic procession of extinction. Evaluation of the potential danger to the conservation of the Amur leopard originating from disease urgently needs to be studied. Unfortunately, research on the potential risk to Amur leopards caused by disease is rare. In terms of parasitic diseases that affect this species, even basic data for parasitic fauna are absent. The aim of this study is to acquire this knowledge to improve the general understanding of Amur leopard parasites. Seven parasite species, including 3 nematodes (Toxocara cati, a capillarid-type parasite, and a Metastrongyloidea-type parasite), 2 cestodes (Spirometra sp. and Taenia sp.), 1 trematode (Paragonimus sp.), and 1 protozoan (Cystoisospora felis), were found in this research. Toxocara cati occurred most frequently, followed by Spirometra sp.
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Affiliation(s)
- Zhijun Hou
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin, China
| | - Zhiwei Peng
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin, China
| | - Yao Ning
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin, China
| | - Dan Liu
- Heilongjiang Siberian Tiger Park, Harbin, China
| | - Hongliang Chai
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin, China
| | - Guangshun Jiang
- College of Wildlife and Protected Area, Northeast Forestry University, Harbin, China
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15
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Raudino HC, Tyne JA, Smith A, Ottewell K, McArthur S, Kopps AM, Chabanne D, Harcourt RG, Pirotta V, Waples K. Challenges of collecting blow from small cetaceans. Ecosphere 2019. [DOI: 10.1002/ecs2.2901] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Affiliation(s)
- Holly C. Raudino
- Biodiversity and Conservation Science Department of Biodiversity, Conservation and Attractions Kensington Western Australia Australia
| | - Julian A. Tyne
- Environmental and Conservation Sciences Murdoch University Perth Western Australia Australia
- Aquatic Megafauna Research Unit Centre for Sustainable Aquatic Ecosystems Harry Butler Institute Murdoch University Perth Western Australia Australia
| | - Alastair Smith
- Heliguy Scientific Pty. Ltd Sydney New South Wales Australia
| | - Kym Ottewell
- Biodiversity and Conservation Science Department of Biodiversity, Conservation and Attractions Kensington Western Australia Australia
| | - Shelley McArthur
- Biodiversity and Conservation Science Department of Biodiversity, Conservation and Attractions Kensington Western Australia Australia
| | | | - Delphine Chabanne
- Environmental and Conservation Sciences Murdoch University Perth Western Australia Australia
- Aquatic Megafauna Research Unit Centre for Sustainable Aquatic Ecosystems Harry Butler Institute Murdoch University Perth Western Australia Australia
| | - Robert G. Harcourt
- Marine Predator Research Group Department of Biological Sciences Macquarie University Sydney New South Wales Australia
| | - Vanessa Pirotta
- Marine Predator Research Group Department of Biological Sciences Macquarie University Sydney New South Wales Australia
| | - Kelly Waples
- Biodiversity and Conservation Science Department of Biodiversity, Conservation and Attractions Kensington Western Australia Australia
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Mingramm FMJ, Dunlop RA, Blyde D, Whitworth DJ, Keeley T. Evaluation of respiratory vapour and blubber samples for use in endocrine assessments of bottlenose dolphins (Tursiops spp.). Gen Comp Endocrinol 2019; 274:37-49. [PMID: 30605661 DOI: 10.1016/j.ygcen.2018.12.015] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2018] [Revised: 11/30/2018] [Accepted: 12/30/2018] [Indexed: 12/13/2022]
Abstract
Blubber and respiratory vapour ('blow') are now commonly used for endocrine studies on cetaceans, primarily because they can be obtained using minimally invasive methods. For many species, these samples have yet to be validated for these purposes. The objective of this study was to examine the performance of blow and blubber hormone monitoring, relative to serum hormone monitoring, for evaluating the reproductive and adrenal condition of captive bottlenose dolphins (Tursiops spp.). Eighteen bottlenose dolphins were sampled five times for serum and blow and twice for blubber throughout a one-year period. Concentrations of progesterone, testosterone, oestradiol and cortisol were measured in each sample type. Hormone levels were examined in relation to dolphin age, sex, reproductive status, season, time of sample collection (morning/afternoon) and collection type (in- or out-of-water sampling). Patterns in hormone levels were similar for serum and blubber. For instance, in both sample types, progesterone levels were significantly higher in pregnant (serum: 34.10 ± 8.64 ng/mL; blubber: 13.01 ± 0.72 ng/g) than in non-pregnant females (serum: 0.32 ± 0.09 ng/mL; blubber: 1.17 ± 0.10 ng/g). This pattern was not detected in blow, primarily because seawater contamination, nylon sampling materials and variable sample volumes influenced measured concentrations. In addition, the respiratory water content of a blow sample is known to affect measured hormone levels. Two methods were trialled to control for variability in sample volumes and dilution: (1) normalising blow hormone concentrations relative to urea nitrogen levels (a potential endogenous standard), and (2) measuring the relative proportions (i.e. ratios) of blow hormones. These correction measures had little influence on blow hormone results. Further refinement of blow hormone monitoring methods is required before they can be used for reproductive or adrenal assessments of bottlenose dolphins. Blubber, on the other hand, should be a suitable proxy for serum when attempting to classify pregnancy status and male maturity in these species.
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Affiliation(s)
- F M J Mingramm
- Cetacean Ecology and Acoustics Laboratory, School of Veterinary Science, The University of Queensland, Gatton, Queensland 4343, Australia; Wildlife Endocrinology Lab, School of Agriculture and Food Science, The University of Queensland, Gatton, Queensland 4343, Australia.
| | - R A Dunlop
- Cetacean Ecology and Acoustics Laboratory, School of Veterinary Science, The University of Queensland, Gatton, Queensland 4343, Australia
| | - D Blyde
- SeaWorld Australia, Gold Coast, Queensland 4217, Australia
| | - D J Whitworth
- School of Veterinary Science, The University of Queensland, Gatton, Queensland 4343, Australia; Australian Institute for Bioengineering and Nanotechnology, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - T Keeley
- Wildlife Endocrinology Lab, School of Agriculture and Food Science, The University of Queensland, Gatton, Queensland 4343, Australia
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17
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Vail CS, Reiss D, Brakes P, Butterworth A. Potential Welfare Impacts of Chase and Capture of Small Cetaceans during Drive Hunts in Japan. J APPL ANIM WELF SCI 2019; 23:193-208. [PMID: 30806084 DOI: 10.1080/10888705.2019.1574576] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Drive hunts are a method to herd, capture and kill small cetaceans (whales and dolphins) in coastal waters of some countries including Japan and the Faroe Islands. In Japan, these methods are often associated with the acquisition of live dolphins for international marine parks and aquaria. During the hunts, dolphins are herded by a flotilla of fishing vessels and loud underwater noise created by fishermen banging hammers on metal poles. The prolonged and strenuous chase and use of sound barriers to herd, capture, and restrain the dolphins can result in acute stress and injury. The authors review physiological and behavioral data pertaining to chase, encirclement, and live capture of dolphins and draw comparisons between chase and capture data for marine and terrestrial species. This analysis raises substantial welfare concerns associated with the hunts and acquisition of dolphins from such capture operations. The authors assert that this data detailing the negative impacts of chase, herding and handling (capture) of small cetaceans renders these hunts inherently inhumane and should inform policy relating to the collection and management of dolphins in the wild.
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Affiliation(s)
| | - Diana Reiss
- Department of Psychology, Hunter College, City University of New York, New York, NY, USA
| | - Philippa Brakes
- Centre for Ecology and Conservation, University of Exeter, Tremough, Cornwall, UK.,Whale and Dolphin Conservation (WDC), Wiltshire, UK
| | - Andrew Butterworth
- Clinical Veterinary School, University of Bristol Veterinary School, Langford, UK
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18
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Edwards KL, Edes AN, Brown JL. Stress, Well-Being and Reproductive Success. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2019; 1200:91-162. [DOI: 10.1007/978-3-030-23633-5_5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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19
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Baleen whale cortisol levels reveal a physiological response to 20th century whaling. Nat Commun 2018; 9:4587. [PMID: 30389921 PMCID: PMC6215000 DOI: 10.1038/s41467-018-07044-w] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2018] [Accepted: 10/09/2018] [Indexed: 01/15/2023] Open
Abstract
One of the most important challenges researchers and managers confront in conservation ecology is predicting a population's response to sub-lethal stressors. Such predictions have been particularly elusive when assessing responses of large marine mammals to past anthropogenic pressures. Recently developed techniques involving baleen whale earplugs combine age estimates with cortisol measurements to assess spatial and temporal stress/stressor relationships. Here we show a relationship between baseline-corrected cortisol levels and corresponding whaling counts of fin, humpback, and blue whales in the Northern Hemisphere spanning the 20th century. We also model the impact of alternative demographic and environmental factors and determine that increased anomalies of sea surface temperature over a 46-year mean (1970-2016) were positively associated with cortisol levels. While industrial whaling can deplete populations by direct harvest, our data underscore a widespread stress response in baleen whales that is peripheral to whaling activities or associated with other anthropogenic change.
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20
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Burgess EA, Hunt KE, Kraus SD, Rolland RM. Quantifying hormones in exhaled breath for physiological assessment of large whales at sea. Sci Rep 2018; 8:10031. [PMID: 30018379 PMCID: PMC6050234 DOI: 10.1038/s41598-018-28200-8] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2018] [Accepted: 05/09/2018] [Indexed: 01/15/2023] Open
Abstract
Exhaled breath analysis is a non-invasive assessment tool that has shown promise in human diagnostics, and could greatly benefit research, management, and conservation of large whales. However, hormone assessment of whale respiratory vapor (blow) has been challenged by variable water content and unknown total volume of collected samples. To advance this technique, we investigated urea (a compound present in narrow range in circulation) as a normalizing factor to correct for blow sample concentration. Normalized progesterone, testosterone, and cortisol concentrations of 100 blow samples from 46 photo-identified North Atlantic right whales (Eubalaena glacialis) were more biologically relevant compared to absolute estimates, varying by sex, age class, or individual. Progesterone was elevated in adult females compared with other cohorts and highest in one independently confirmed pregnant female. For both sexes, testosterone was two-fold higher in reproductively mature whales but studied adult females showed the widest variation. Cortisol was present in relatively low concentrations in blow and demonstrated variation between individual whales, suggesting potential for studies of individual differences in adrenal activity. Incorporation of methodologies that normalize sample concentration are essential for blow hormone analysis of free-swimming whales, and measurement of urea could be used to optimize non-invasive physiological assessment of whales.
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Affiliation(s)
- Elizabeth A Burgess
- Anderson Cabot Center for Ocean Life, New England Aquarium, Boston, 02110, USA.
| | - Kathleen E Hunt
- Center for Bioengineering Innovation, Northern Arizona University, Flagstaff, AZ, 86011, USA
| | - Scott D Kraus
- Anderson Cabot Center for Ocean Life, New England Aquarium, Boston, 02110, USA
| | - Rosalind M Rolland
- Anderson Cabot Center for Ocean Life, New England Aquarium, Boston, 02110, USA
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21
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Mooney TA, Castellote M, Quakenbush L, Hobbs R, Gaglione E, Goertz C. Variation in hearing within a wild population of beluga whales (Delphinapterus leucas). J Exp Biol 2018; 221:221/9/jeb171959. [DOI: 10.1242/jeb.171959] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2017] [Accepted: 03/12/2018] [Indexed: 10/17/2022]
Abstract
ABSTRACT
Documenting hearing abilities is vital to understanding a species’ acoustic ecology and for predicting the impacts of increasing anthropogenic noise. Cetaceans use sound for essential biological functions such as foraging, navigation and communication; hearing is considered to be their primary sensory modality. Yet, we know little regarding the hearing of most, if not all, cetacean populations, which limits our understanding of their sensory ecology, population level variability and the potential impacts of increasing anthropogenic noise. We obtained audiograms (5.6–150 kHz) of 26 wild beluga whales to measure hearing thresholds during capture–release events in Bristol Bay, AK, USA, using auditory evoked potential methods. The goal was to establish the baseline population audiogram, incidences of hearing loss and general variability in wild beluga whales. In general, belugas showed sensitive hearing with low thresholds (<80 dB) from 16 to 100 kHz, and most individuals (76%) responded to at least 120 kHz. Despite belugas often showing sensitive hearing, thresholds were usually above or approached the low ambient noise levels measured in the area, suggesting that a quiet environment may be associated with hearing sensitivity and that hearing thresholds in the most sensitive animals may have been masked. Although this is just one wild population, the success of the method suggests that it should be applied to other populations and species to better assess potential differences. Bristol Bay beluga audiograms showed substantial (30–70 dB) variation among individuals; this variation increased at higher frequencies. Differences among individual belugas reflect that testing multiple individuals of a population is necessary to best describe maximum sensitivity and population variance. The results of this study quadruple the number of individual beluga whales for which audiograms have been conducted and provide the first auditory data for a population of healthy wild odontocetes.
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Affiliation(s)
- T. Aran Mooney
- Biology Department, Woods Hole Oceanographic Institution, Woods Hole, MA 02543, USA
| | - Manuel Castellote
- Joint Institute for the Study of the Atmosphere and Ocean (JISAO), University of Washington, Seattle, WA 98105, USA
- Marine Mammal Laboratory, Alaska Fisheries Science Center, National Marine Fisheries Service, Seattle, WA 98115, USA
| | - Lori Quakenbush
- Alaska Department of Fish and Game, Fairbanks, AK 99701, USA
| | - Roderick Hobbs
- Marine Mammal Laboratory, Alaska Fisheries Science Center, National Marine Fisheries Service, Seattle, WA 98115, USA
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Fumagalli M, Cesario A, Costa M, Harraway J, Notarbartolo di Sciara G, Slooten E. Behavioural responses of spinner dolphins to human interactions. ROYAL SOCIETY OPEN SCIENCE 2018; 5:172044. [PMID: 29765660 PMCID: PMC5936925 DOI: 10.1098/rsos.172044] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 03/20/2018] [Indexed: 05/10/2023]
Abstract
There is increasing evidence that whale and dolphin watching activities have detrimental effects on targeted cetacean populations. In Egypt, spinner dolphins regularly occur in the resting areas of Samadai, Satayah and Qubbat'Isa reefs. In-water human interactions with dolphins are regulated with a time-area closure system at Samadai, unregulated at Satayah and non-existent at Qubbat'Isa. This provided an ideal experimental setting to advance our understanding of the effects of tourism on a species highly sensitive to disturbances. Our study confirmed that the intensity and duration of interactions, and therefore, dolphin exposure to tourism, differed among the study sites. Compared with the Qubbat'Isa control site, behavioural reactions to boats and swimmers at the two tourism sites suggested that dolphin rest was disrupted, especially around the middle of the day and especially at Satayah, where dolphin tourism is unregulated. Our results indicate also that the dolphin protection measures at Samadai reduce the level of disturbance. We recommend that similar measures be implemented at other dolphin tourism locations, and that no new operations be initiated until the long-term impacts on dolphin populations are better understood. Our experience emphasizes the need to adopt precautionary approaches in research and management of whale and dolphin watching.
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Affiliation(s)
- Maddalena Fumagalli
- Department of Zoology, University of Otago, 340 Great King Street, Dunedin 9054, New Zealand
- Tethys Research Institute, Viale G.B. Gadio 2, Milano 20121, Italy
- Author for correspondence: Maddalena Fumagalli e-mail:
| | - Amina Cesario
- Tethys Research Institute, Viale G.B. Gadio 2, Milano 20121, Italy
- The Swire Institute of Marine Science, University of Hong Kong, Pokfulam Road, Hong Kong SAR, People's Republic of China
| | - Marina Costa
- Tethys Research Institute, Viale G.B. Gadio 2, Milano 20121, Italy
- South Atlantic Environmental Research Institute (SAERI), Stanley Cottage, Falkland Islands
| | - John Harraway
- Department of Mathematics and Statistics, University of Otago, 730 Cumberland Street, Dunedin 9016, New Zealand
| | | | - Elisabeth Slooten
- Department of Zoology, University of Otago, 340 Great King Street, Dunedin 9054, New Zealand
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Morey JS, Burek Huntington KA, Campbell M, Clauss TM, Goertz CE, Hobbs RC, Lunardi D, Moors AJ, Neely MG, Schwacke LH, Van Dolah FM. De novo transcriptome assembly and RNA-Seq expression analysis in blood from beluga whales of Bristol Bay, AK. Mar Genomics 2017; 35:77-92. [PMID: 28802692 DOI: 10.1016/j.margen.2017.08.001] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 08/01/2017] [Accepted: 08/02/2017] [Indexed: 11/18/2022]
Abstract
Assessing the health of marine mammal sentinel species is crucial to understanding the impacts of environmental perturbations on marine ecosystems and human health. In Arctic regions, beluga whales, Delphinapterus leucas, are upper level predators that may serve as a sentinel species, potentially forecasting impacts on human health. While gene expression profiling from blood transcriptomes has widely been used to assess health status and environmental exposures in human and veterinary medicine, its use in wildlife has been limited due to the lack of available genomes and baseline data. To this end we constructed the first beluga whale blood transcriptome de novo from samples collected during annual health assessments of the healthy Bristol Bay, AK stock during 2012-2014 to establish baseline information on the content and variation of the beluga whale blood transcriptome. The Trinity transcriptome assembly from beluga was comprised of 91,325 transcripts that represented a wide array of cellular functions and processes and was extremely similar in content to the blood transcriptome of another cetacean, the bottlenose dolphin. Expression of hemoglobin transcripts was much lower in beluga (25.6% of TPM, transcripts per million) than has been observed in many other mammals. A T12A amino acid substitution in the HBB sequence of beluga whales, but not bottlenose dolphins, was identified and may play a role in low temperature adaptation. The beluga blood transcriptome was extremely stable between sex and year, with no apparent clustering of samples by principle components analysis and <4% of genes differentially expressed (EBseq, FDR<0.05). While the impacts of season, sexual maturity, disease, and geography on the beluga blood transcriptome must be established, the presence of transcripts involved in stress, detoxification, and immune functions indicate that blood gene expression analyses may provide information on health status and exposure. This study provides a wealth of transcriptomic data on beluga whales and provides a sizeable pool of preliminary data for comparison with other studies in beluga whale.
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Affiliation(s)
- Jeanine S Morey
- Hollings Marine Laboratory, National Centers for Coastal Ocean Science, National Ocean Service, NOAA, 331 Fort Johnson Road, Charleston, SC 29412, USA; Jardon and Howard Technologies Incorporated, 2710 Discovery Drive, Orlando, FL 32826, USA.
| | | | | | - Tonya M Clauss
- Georgia Aquarium, 225 Baker Street, Atlanta, GA 30313, USA
| | | | - Roderick C Hobbs
- National Marine Mammal Laboratory, Alaska Fisheries Science Center, National Marine Fisheries Service, NOAA, 7600 Sand Point Way N.E., Seattle, WA 95115, USA
| | - Denise Lunardi
- Department of Life Sciences and Biotechnology, University of Ferrara, via L. Borsari 46, 44121 Ferrara, Italy
| | - Amanda J Moors
- Hollings Marine Laboratory, National Institute of Standards and Technology, 331 Fort Johnson Road, Charleston, SC 29412, USA
| | - Marion G Neely
- Hollings Marine Laboratory, National Centers for Coastal Ocean Science, National Ocean Service, NOAA, 331 Fort Johnson Road, Charleston, SC 29412, USA; Jardon and Howard Technologies Incorporated, 2710 Discovery Drive, Orlando, FL 32826, USA
| | - Lori H Schwacke
- Hollings Marine Laboratory, National Centers for Coastal Ocean Science, National Ocean Service, NOAA, 331 Fort Johnson Road, Charleston, SC 29412, USA
| | - Frances M Van Dolah
- Hollings Marine Laboratory, National Centers for Coastal Ocean Science, National Ocean Service, NOAA, 331 Fort Johnson Road, Charleston, SC 29412, USA
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Hayden M, Bhawal R, Escobedo J, Harmon C, O'Hara TM, Klein D, San-Francisco S, Zabet-Moghaddam M, Godard-Codding CAJ. Nanospray liquid chromatography/tandem mass spectrometry analysis of steroids from gray whale blubber. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2017; 31:1088-1094. [PMID: 28423207 DOI: 10.1002/rcm.7884] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Revised: 04/11/2017] [Accepted: 04/12/2017] [Indexed: 06/07/2023]
Abstract
RATIONALE Analysis of steroids from precious blubber biopsies obtained from marine mammals, especially endangered species, can provide valuable information on their endocrine status. Challenges with currently used ELISA methodology include lack of absolute quantitation and incompatibility with multiple steroids analysis due to limited biopsy mass. Development of a sensitive, accurate analytical method for this purpose is critical. METHODS A nanospray liquid chromatography/tandem mass spectrometry (nanoLC/MS/MS) method was validated for sensitive, specific and quantitative analysis of three steroid hormones, without derivatization, extracted from 50 mg blubber samples. Data was acquired with an LTQ XL ion trap mass spectrometer in positive ion mode, using single reaction monitoring. All three steroids were analyzed in a single run. Cholic acid was used as a surrogate internal standard for quantitation due to its steroidal structure and lack of measurable endogenous levels in blubber. RESULTS The lowest limits of quantitation for progesterone, testosterone, and hydrocortisone were significantly improved compared to previous studies using conventional LC/MS/MS. The lowest limit of detection was 7 fg/μL using a 1 μL injection volume. Calibration curves for steroid quantification showed good linearity (r2 >0.99) between 14 and 3620 fg/μL, and accuracy was <20% for interday and <10% for intraday. After validation, the method was successfully applied to quantification of steroids in gray whale blubber samples. CONCLUSIONS The nanoLC/MS/MS method is more sensitive than traditional LC/MS/MS for steroid analysis. It is also compatible with other important biopsy analyses due to its small blubber mass requirement. This will benefit the reproductive and stress assessments for all marine mammals, particularly endangered populations. Copyright © 2017 John Wiley & Sons, Ltd.
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Affiliation(s)
- Mary Hayden
- The Institute of Environmental and Human Health, Texas Tech University, Lubbock, TX, USA
| | - Ruchika Bhawal
- Center for Biotechnology and Genomics, Texas Tech University, Lubbock, TX, USA
| | - John Escobedo
- Center for Biotechnology and Genomics, Texas Tech University, Lubbock, TX, USA
| | - Clinton Harmon
- Center for Biotechnology and Genomics, Texas Tech University, Lubbock, TX, USA
| | - Todd M O'Hara
- Department of Veterinary Medicine, University of Alaska Fairbanks, Fairbanks, AK, USA
| | - David Klein
- The Institute of Environmental and Human Health, Texas Tech University, Lubbock, TX, USA
| | - Susan San-Francisco
- Center for Biotechnology and Genomics, Texas Tech University, Lubbock, TX, USA
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25
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Richard JT, Robeck TR, Osborn SD, Naples L, McDermott A, LaForge R, Romano TA, Sartini BL. Testosterone and progesterone concentrations in blow samples are biologically relevant in belugas (Delphinapterus leucas). Gen Comp Endocrinol 2017; 246:183-193. [PMID: 27989435 DOI: 10.1016/j.ygcen.2016.12.006] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/13/2016] [Revised: 12/06/2016] [Accepted: 12/11/2016] [Indexed: 12/22/2022]
Abstract
Steroid hormone analysis in blow (respiratory vapor) may provide a minimally invasive way to assess the reproductive status of wild cetaceans. Biological validation of the method is needed to allow for the interpretation of hormone measurements in blow samples. Utilizing samples collected from trained belugas (Delphinapterus leucas, n=20), enzyme immunoassays for testosterone and progesterone were validated for use with beluga blow samples. Testosterone concentrations in 40 matched blood and blow samples collected from 4 male belugas demonstrated a positive correlation (R2=0.52, p<0.0001). Progesterone concentrations in 64 matching blood and blow samples from 11 females were also positively correlated (R2=0.60, p<0.0001). Testosterone concentrations (mean±SD) in blow samples collected from adult males (119.3±14.2pg/ml) were higher (p<0.01) than that of a juvenile male (<8years) (59.4±6.5pg/ml) or female belugas (54.1±25.7pg/ml). Among adult males, testosterone concentrations in blow demonstrated a seasonal pattern of secretion, with peak secretion occurring during the breeding season (February-April, 136.95±33.8pg/ml). Progesterone concentrations in blow varied by reproductive status; pregnant females (410.6±87.8pg/ml) and females in the luteal phase of the estrous cycle (339.5±51.0pg/ml) had higher (p<0.0001) blow progesterone concentrations than non-pregnant females without a corpus luteum (242.5±27.3pg/ml). Results indicate that blow sample analysis can be used to detect variation in reproductive states associated with large differences in circulating testosterone or progesterone in belugas.
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Affiliation(s)
- Justin T Richard
- University of Rhode Island, 120 Flagg Rd, Kingston, RI 02881, USA; Mystic Aquarium, a division of Sea Research Foundation, 55 Coogan Blvd, Mystic, CT 06355, USA.
| | - Todd R Robeck
- SeaWorld and Busch Gardens Reproductive Research Center, SeaWorld Parks and Entertainment, 2595 Ingraham Road, San Diego, CA 92019, USA
| | - Steven D Osborn
- SeaWorld San Antonio, 10500 SeaWorld Drive, San Antonio, TX 78251, USA
| | - Lisa Naples
- Shedd Aquarium, 1200 S. Lake Shore Drive, Chicago, IL 60605, USA
| | | | - Robert LaForge
- University of Rhode Island, 120 Flagg Rd, Kingston, RI 02881, USA
| | - Tracy A Romano
- Mystic Aquarium, a division of Sea Research Foundation, 55 Coogan Blvd, Mystic, CT 06355, USA
| | - Becky L Sartini
- University of Rhode Island, 120 Flagg Rd, Kingston, RI 02881, USA
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26
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Heenehan HL, Van Parijs SM, Bejder L, Tyne JA, Johnston DW. Differential effects of human activity on Hawaiian spinner dolphins in their resting bays. Glob Ecol Conserv 2017. [DOI: 10.1016/j.gecco.2017.02.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
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27
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Espinosa‐de Aquino W, Olvera‐Ramírez A, Arellano‐Carbajal F, Lanz‐Mendoza H, Villagrán‐Herrera E, Acevedo‐Whitehouse K. Protein and
RNA
extraction from mucosal swabs: a minimally invasive source of ecological data for studies of natural populations. Methods Ecol Evol 2016. [DOI: 10.1111/2041-210x.12680] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Wendy Espinosa‐de Aquino
- Unit for Basic and Applied Microbiology School of Natural Sciences Autonomous University of Queretaro Santiago de Querétaro Queretaro 76230 Mexico
| | - Andrea Olvera‐Ramírez
- Department of Veterinary Medicine School of Natural Sciences Autonomous University of Queretaro Santiago de Querétaro Queretaro 76230 Mexico
| | - Fausto Arellano‐Carbajal
- Unit for Basic and Applied Microbiology School of Natural Sciences Autonomous University of Queretaro Santiago de Querétaro Queretaro 76230 Mexico
| | - Humberto Lanz‐Mendoza
- Center for Infectious Diseases National Institute of Public Health Cuernavaca Morelos 62100 Mexico
| | - Elena Villagrán‐Herrera
- School of Medicine Autonomous University of Queretaro Santiago de Querétaro Queretaro 76230 Mexico
| | - Karina Acevedo‐Whitehouse
- Unit for Basic and Applied Microbiology School of Natural Sciences Autonomous University of Queretaro Santiago de Querétaro Queretaro 76230 Mexico
- The Marine Mammal Center 2000 Bunker Road Sausalito CA 94965 USA
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Burgess EA, Hunt KE, Kraus SD, Rolland RM. Get the most out of blow hormones: validation of sampling materials, field storage and extraction techniques for whale respiratory vapour samples. CONSERVATION PHYSIOLOGY 2016; 4:cow024. [PMID: 27928506 PMCID: PMC5001149 DOI: 10.1093/conphys/cow024] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/29/2015] [Revised: 05/12/2016] [Accepted: 05/14/2016] [Indexed: 05/12/2023]
Abstract
Studies are progressively showing that vital physiological data may be contained in the respiratory vapour (blow) of cetaceans. Nonetheless, fundamental methodological issues need to be addressed before hormone analysis of blow can become a reliable technique. In this study, we performed controlled experiments in a laboratory setting, using known doses of pure parent hormones, to validate several technical factors that may play a crucial role in hormone analyses. We evaluated the following factors: (i) practical field storage of samples on small boats during daylong trips; (ii) efficiency of hormone extraction methods; and (iii) assay interference of different sampler types (i.e. veil nylon, nitex nylon mesh and polystyrene dish). Sampling materials were dosed with mock blow samples of known mixed hormone concentrations (progesterone, 17β-estradiol, testosterone, cortisol, aldosterone and triiodothyronine), designed to mimic endocrine profiles characteristic of pregnant females, adult males, an adrenal glucocorticoid response or a zero-hormone control (distilled H2O). Results showed that storage of samples in a cooler on ice preserved hormone integrity for at least 6 h (P = 0.18). All sampling materials and extraction methods yielded the correct relative patterns for all six hormones. However, veil and nitex mesh produced detectable assay interference (mean 0.22 ± 0.04 and 0.18 ± 0.03 ng/ml, respectively), possibly caused by some nylon-based component affecting antibody binding. Polystyrene dishes were the most efficacious sampler for accuracy and precision (P < 0.001), but required an ethanol rinse for improved progesterone recovery (increased 81%; P < 0.001). Awareness of assay interference from exogenous materials is crucial to future studies. This study establishes critical groundwork to help ensure that hormones can be measured accurately in samples obtained from field collections of whale blow.
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Affiliation(s)
- Elizabeth A. Burgess
- John H. Prescott Marine Laboratory, New England Aquarium, 1 Central Wharf, Boston, MA 02110, USA
| | - Kathleen E. Hunt
- John H. Prescott Marine Laboratory, New England Aquarium, 1 Central Wharf, Boston, MA 02110, USA
| | - Scott D. Kraus
- John H. Prescott Marine Laboratory, New England Aquarium, 1 Central Wharf, Boston, MA 02110, USA
| | - Rosalind M. Rolland
- John H. Prescott Marine Laboratory, New England Aquarium, 1 Central Wharf, Boston, MA 02110, USA
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Kershaw JL, Hall AJ. Seasonal variation in harbour seal (Phoca vitulina) blubber cortisol - A novel indicator of physiological state? Sci Rep 2016; 6:21889. [PMID: 26906193 PMCID: PMC4764809 DOI: 10.1038/srep21889] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2015] [Accepted: 02/03/2016] [Indexed: 01/07/2023] Open
Abstract
Cortisol is one of the main glucocorticoid hormones involved in both the mammalian stress response, and in fat metabolism and energy regulation, making it of increasing interest as a biomarker for stress, health and overall physiological state. However, transient stress responses to animal handling and sampling may be important sources of measurement artefact when investigating circulating concentrations of this hormone in wildlife. Here, cortisol concentrations were measured in the plasma and, for the first time, in the blubber of live captured adult harbour seals (Phoca vitulina). Plasma cortisol concentrations were positively correlated with capture time, suggesting that they were largely driven by a stress response to the capture event. In contrast, blubber cortisol concentrations were shown not to be significantly affected by capture time and varied significantly by sex and by season, with higher concentrations during natural fasting periods of their life cycle, particularly during the moult. These results suggest that cortisol may play a key role in increased fat metabolism during highly energetically demanding periods, and that blubber concentrations have the potential to be used as physiological state indicators in phocid seals.
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Affiliation(s)
- Joanna L Kershaw
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife. KY16 8LB, UK
| | - Ailsa J Hall
- Sea Mammal Research Unit, Scottish Oceans Institute, University of St Andrews, St Andrews, Fife. KY16 8LB, UK
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