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Melica V, Thornton SJ. Killer whale fecal samples: How to get the most out of a single extraction. Gen Comp Endocrinol 2024; 354:114544. [PMID: 38705419 DOI: 10.1016/j.ygcen.2024.114544] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/27/2023] [Revised: 04/19/2024] [Accepted: 04/30/2024] [Indexed: 05/07/2024]
Abstract
Fecal samples are a non-invasive and relatively accessible matrix for investigating physiological processes in resident killer whale (Orcinus orca) populations. The high lipid content of the diet (primarily salmonids) leads to lower density fecal material and slower dispersion, facilitating sample collection. As fecal discharge is relatively infrequent and the volume of sample is variable, maximizing analytical options is an important consideration. Here we present an extraction methodology to measure hormones and lipid content from the same fecal aliquot. Lipid extractions are commonly conducted using chloroform and methanol from Folch or Bligh and Dyer (B&D), while alcohol is the primary solvent for hormone extraction. We evaluated the possibility of using the methanol layer from lipid extractions to assess fecal steroid hormone levels. Folch and B&D methanol residues were assayed form metabolites of progesterone (PMs) and corticosterone (GCs), and results were compared to aliquots extracted in 70 % ethanol. Hormone concentrations measured in the methanol layer from Folch and B&D extractions were 55 % to 79 % lower than concentrations in 70 % ethanol. We developed mathematical corrections, using linear regression models fitted to Folch or B&D methanol vs 70 % ethanol hormone concentrations (p < 0.01). Fecal concentrations of PMs and GCs from methanol extractions were biologically validated and are significantly higher in confirmed pregnant females compared to non-pregnant individuals (p < 0.05). This study demonstrates that lipid extraction protocols may be used for the analysis of multiple biomarkers, maximizing the use of small-volume samples.
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Affiliation(s)
- V Melica
- Marine Mammal Conservation Physiology Program, Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, Canada
| | - S J Thornton
- Marine Mammal Conservation Physiology Program, Fisheries and Oceans Canada, 4160 Marine Drive, West Vancouver, BC, Canada.
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2
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Ross ARS, Liao X, Brown TM. Simultaneous determination of steroid hormones and pharmaceuticals in killer whale ( Orcinus orca) faecal samples by liquid chromatography tandem mass spectrometry. CONSERVATION PHYSIOLOGY 2023; 11:coad081. [PMID: 38026807 PMCID: PMC10660373 DOI: 10.1093/conphys/coad081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 08/03/2023] [Accepted: 10/10/2023] [Indexed: 12/01/2023]
Abstract
We describe a non-invasive method for profiling selected hormones, pharmaceuticals and personal care products (PPCPs) in killer whales (Orcinus orca) based on analysis of faecal samples by liquid chromatography tandem mass spectrometry (LC-MS/MS). The method targets 21 compounds of interest including glucocorticoids, mineralocorticoids, androgens, estrogens, progestogens, selective serotonin uptake inhibitors and an antibacterial/antifungal agent. This method is suitable for routine simultaneous determination of target compounds in killer whale faecal samples as well as validation of immunoassays for the detection and measurement of steroid hormones in faeces. The optimized method involves extraction of freeze-dried faecal material with reagent alcohol and water followed by isolation of the analytes using solid phase extraction with hydrophilic-lipophilic balance cartridges and liquid-liquid extraction with methyl tertiary-butyl ether. Reconstituted extracts were analysed by LC-MS/MS using an electrospray ionization interface. Method limit of quantification ranged from 0.06 to 45.2 ng/g in freeze-dried faecal samples. Except for sertraline, triclosan and estradiol (which was not recovered at the lowest spiked concentration), average intra- and inter-day precisions were within 10%, and average recoveries were between 89.3% and 129.3%, for faecal samples spiked with 5.3, 26.7 or 133 ng/g of each analyte. The method was applied successfully to the analysis of hormones and PPCPs in whale faeces during which 17α-hydroxyprogesterone, a common intermediate in steroid biosynthesis that cross-reacts with precursors and sulphated conjugates in immunoassays, was identified and quantified in all samples.
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Affiliation(s)
- Andrew R S Ross
- Fisheries and Oceans Canada, 9860 West Saanich Road, Sidney, BC, V8L 4B2, Canada
| | - Xiangjun Liao
- Fisheries and Oceans Canada, 9860 West Saanich Road, Sidney, BC, V8L 4B2, Canada
| | - Tanya M Brown
- Fisheries and Oceans Canada, 9860 West Saanich Road, Sidney, BC, V8L 4B2, Canada
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3
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Pirotta E, Fernandez Ajó A, Bierlich KC, Bird CN, Buck CL, Haver SM, Haxel JH, Hildebrand L, Hunt KE, Lemos LS, New L, Torres LG. Assessing variation in faecal glucocorticoid concentrations in gray whales exposed to anthropogenic stressors. CONSERVATION PHYSIOLOGY 2023; 11:coad082. [PMID: 38026800 PMCID: PMC10660368 DOI: 10.1093/conphys/coad082] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 10/05/2023] [Accepted: 10/10/2023] [Indexed: 12/01/2023]
Abstract
Understanding how individual animals respond to stressors behaviourally and physiologically is a critical step towards quantifying long-term population consequences and informing management efforts. Glucocorticoid (GC) metabolite accumulation in various matrices provides an integrated measure of adrenal activation in baleen whales and could thus be used to investigate physiological changes following exposure to stressors. In this study, we measured GC concentrations in faecal samples of Pacific Coast Feeding Group (PCFG) gray whales (Eschrichtius robustus) collected over seven consecutive years to assess the association between GC content and metrics of exposure to sound levels and vessel traffic at different temporal scales, while controlling for contextual variables such as sex, reproductive status, age, body condition, year, time of year and location. We develop a Bayesian Generalized Additive Modelling approach that accommodates the many complexities of these data, including non-linear variation in hormone concentrations, missing covariate values, repeated samples, sampling variability and some hormone concentrations below the limit of detection. Estimated relationships showed large variability, but emerging patterns indicate a strong context-dependency of physiological variation, depending on sex, body condition and proximity to a port. Our results highlight the need to control for baseline hormone variation related to context, which otherwise can obscure the functional relationship between faecal GCs and stressor exposure. Therefore, extensive data collection to determine sources of baseline variation in well-studied populations, such as PCFG gray whales, could shed light on cetacean stress physiology and be used to extend applicability to less-well-studied taxa. GC analyses may offer greatest utility when employed as part of a suite of markers that, in aggregate, provide a multivariate measure of physiological status, better informing estimates of individuals' health and ultimately the consequences of anthropogenic stressors on populations.
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Affiliation(s)
- Enrico Pirotta
- Centre for Research into Ecological and Environmental Modelling, University of St Andrews, The Observatory, Buchanan Gardens, St Andrews, Fife, Scotland KY16 9LZ, UK
| | - Alejandro Fernandez Ajó
- Geospatial Ecology of Marine Megafauna Lab, Marine Mammal Institute, Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, 2030 SE Marine Science Drive, Newport, OR 97365, USA
| | - KC Bierlich
- Geospatial Ecology of Marine Megafauna Lab, Marine Mammal Institute, Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, 2030 SE Marine Science Drive, Newport, OR 97365, USA
| | - Clara N Bird
- Geospatial Ecology of Marine Megafauna Lab, Marine Mammal Institute, Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, 2030 SE Marine Science Drive, Newport, OR 97365, USA
| | - C Loren Buck
- Department of Biological Sciences, Northern Arizona University, 617 S. Beaver St., Flagstaff, AZ 86011, USA
| | - Samara M Haver
- Cooperative Institute for Marine Ecosystem and Resources Studies, Oregon State University, 2030 SE Marine Science Drive, Newport, OR 97365, USA
- Department of Fisheries, Wildlife, and Conservation Sciences, Oregon State University, 104 Nash Hall, Corvallis, OR 97331, USA
| | - Joseph H Haxel
- Pacific Northwest National Laboratory, Coastal Sciences Division, 1529 W. Sequim Bay Rd., Sequim, WA 98362, USA
| | - Lisa Hildebrand
- Geospatial Ecology of Marine Megafauna Lab, Marine Mammal Institute, Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, 2030 SE Marine Science Drive, Newport, OR 97365, USA
| | - Kathleen E Hunt
- Smithsonian-Mason School of Conservation & Department of Biology, George Mason University, 1500 Remount Rd, Front Royal, VA 22630, USA
| | - Leila S Lemos
- Institute of Environment, Florida International University, 3000 NE 151st St, North Miami, FL 33181, USA
| | - Leslie New
- Department of Mathematics, Computer Science and Statistics, Ursinus College, 601 E Main St, Collegeville, PA 19426, USA
| | - Leigh G Torres
- Geospatial Ecology of Marine Megafauna Lab, Marine Mammal Institute, Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, 2030 SE Marine Science Drive, Newport, OR 97365, USA
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Behringer V, Heistermann M, Malaivijitnond S, Schülke O, Ostner J. Developmental and environmental modulation of fecal thyroid hormone levels in wild Assamese macaques (Macaca assamensis). Am J Primatol 2023; 85:e23530. [PMID: 37365835 DOI: 10.1002/ajp.23530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 06/09/2023] [Accepted: 06/18/2023] [Indexed: 06/28/2023]
Abstract
Thyroid hormones are key modulators of development, as well as mediators of environmental conditions, by regulating developmental processes and metabolism in primates. Hormone measurement in noninvasively collected samples, that is, feces and urine, is a valuable tool for studying the endocrine function of wildlife, and recent studies have demonstrated the feasibility of measuring thyroid hormones in fecal samples of zoo-housed and wild nonhuman primates. Our study aimed to (i) validate the measurement of immunoreactive fecal total triiodothyronine (IF-T3) in wild Assamese macaques (Macaca assamensis) and (ii) to investigate its developmental changes and its response to environmental changes, including stress responses, in immature individuals. Fecal samples and environmental parameters were collected from individuals of three social groups of wild Assamese macaques living at Phu Khieo Wildlife Sanctuary, Northeastern Thailand. Our study confirmed the methodological feasibility and biological validity of measuring IF-T3 in this population. Specifically, the biological validation demonstrated higher IF-T3 levels in immatures compared to adults, and higher levels in females during late gestation compared to the preconception stage. Our analysis of IF-T3 levels in developing immature macaques revealed a significant increase with age. Furthermore, we found a positive association between IF-T3 and immunoreactive fecal glucocorticoid levels, an indicator of the physiological stress response. Neither minimum temperature nor fruit abundance predicted variation in IF-T3 levels in the immatures. Our findings indicate the possibility for differing effects of climatic factors and food availability on thyroid hormone level changes in immature versus adult animals and in wild compared to experimental conditions. Overall, our study provides the basis for further investigations into the role of thyroid hormones in shaping species-specific traits, growth, and overall primate development.
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Affiliation(s)
- Verena Behringer
- Endocrinology Laboratory, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany
- Leibniz ScienceCampus Primate Cognition, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany
| | - Michael Heistermann
- Endocrinology Laboratory, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany
| | - Suchinda Malaivijitnond
- Department of Biology, Faculty of Science, Chulalongkorn University, Bangkok, Thailand
- National Primate Research Center of Thailand, Chulalongkorn University, Saraburi, Thailand
| | - Oliver Schülke
- Leibniz ScienceCampus Primate Cognition, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany
- Behavioral Ecology Department, University of Goettingen, Göttingen, Germany
- Primate Social Evolution Group, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany
| | - Julia Ostner
- Leibniz ScienceCampus Primate Cognition, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany
- Behavioral Ecology Department, University of Goettingen, Göttingen, Germany
- Primate Social Evolution Group, German Primate Center, Leibniz Institute for Primate Research, Göttingen, Germany
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Fernandez Ajó A, Pirotta E, Bierlich KC, Hildebrand L, Bird CN, Hunt KE, Buck CL, New L, Dillon D, Torres LG. Assessment of a non-invasive approach to pregnancy diagnosis in gray whales through drone-based photogrammetry and faecal hormone analysis. ROYAL SOCIETY OPEN SCIENCE 2023; 10:230452. [PMID: 37476509 PMCID: PMC10354484 DOI: 10.1098/rsos.230452] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 04/07/2023] [Accepted: 06/26/2023] [Indexed: 07/22/2023]
Abstract
Knowledge of baleen whales' reproductive physiology is limited and requires long-term individual-based studies and innovative tools. We used 6 years of individual-level data on the Pacific Coast Feeding Group gray whales to evaluate the utility of faecal progesterone immunoassays and drone-based photogrammetry for pregnancy diagnosis. We explored the variability in faecal progesterone metabolites and body morphology relative to observed reproductive status and estimated the pregnancy probability for mature females of unknown reproductive status using normal mixture models. Individual females had higher faecal progesterone concentrations when pregnant than when presumed non-pregnant. Yet, at the population level, high overlap and variability in progesterone metabolite concentrations occurred between pregnant and non-pregnant groups, limiting this metric for accurate pregnancy diagnosis in gray whales. Alternatively, body width at 50% of the total body length (W50) correctly discriminated pregnant from non-pregnant females at individual and population levels, with high accuracy. Application of the model using W50 metric to mature females of unknown pregnancy status identified eight additional pregnancies with high confidence. Our findings highlight the utility of drone-based photogrammetry to non-invasively diagnose pregnancy in this group of gray whales, and the potential for improved data on reproductive rates for population management of baleen whales generally.
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Affiliation(s)
- A. Fernandez Ajó
- Geospatial Ecology of Marine Megafauna Lab, Marine Mammal Institute, Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, Newport 97365, OR, USA
| | - E. Pirotta
- Centre for Research into Ecological and Environmental Modelling, University of St Andrews, St Andrews, UK
| | - K. C. Bierlich
- Geospatial Ecology of Marine Megafauna Lab, Marine Mammal Institute, Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, Newport 97365, OR, USA
| | - L. Hildebrand
- Geospatial Ecology of Marine Megafauna Lab, Marine Mammal Institute, Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, Newport 97365, OR, USA
| | - C. N. Bird
- Geospatial Ecology of Marine Megafauna Lab, Marine Mammal Institute, Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, Newport 97365, OR, USA
| | - K. E. Hunt
- Smithsonian-Mason School of Conservation, Department of Biology, George Mason University, 1500 Remount Road, Front Royal, VA 22630, USA
| | - C. L. Buck
- Department of Biological Sciences, Northern Arizona University, 617 South Beaver Street, Flagstaff, AZ 86011, USA
| | - L. New
- Ursinus College, 601 East Main Street, Collegeville, PA 19426, USA
| | - D. Dillon
- Department of Biological Sciences, Northern Arizona University, 617 South Beaver Street, Flagstaff, AZ 86011, USA
| | - L. G. Torres
- Geospatial Ecology of Marine Megafauna Lab, Marine Mammal Institute, Department of Fisheries, Wildlife and Conservation Sciences, Oregon State University, Newport 97365, OR, USA
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Lemos LS, Angarica LM, Hauser-Davis RA, Quinete N. Cortisol as a Stress Indicator in Fish: Sampling Methods, Analytical Techniques, and Organic Pollutant Exposure Assessments. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2023; 20:6237. [PMID: 37444085 PMCID: PMC10341563 DOI: 10.3390/ijerph20136237] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/03/2023] [Revised: 06/21/2023] [Accepted: 06/22/2023] [Indexed: 07/15/2023]
Abstract
Cortisol is the main glucocorticoid released during stress responses in most fish and has been employed to investigate different stressors, including organic pollutants. This review discusses shifts in cortisol concentrations and examines different matrix sampling methods (invasive vs. minimally or non-invasive) and the main analytical cortisol determination techniques (immunoassays and liquid chromatography-tandem mass spectrometry). Assessments on organic pollutant exposure in fish and associated adverse effects are also discussed. Studies in this regard may aid in identifying organic pollutant toxicological modes of action, mechanistic response, toxicokinetics, and toxicodynamics, as well as pollution sources and associated health risks in fish, ultimately aiding in the development of effective management strategies to mitigate the impacts of organic pollutants on fish populations and their associated ecosystems.
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Affiliation(s)
- Leila Soledade Lemos
- Institute of Environment, Florida International University, North Miami, FL 33181, USA
- Department of Chemistry and Biochemistry, Florida International University, North Miami, FL 33181, USA
| | - Leo Moreira Angarica
- Department of Chemistry and Biochemistry, Florida International University, North Miami, FL 33181, USA
| | - Rachel Ann Hauser-Davis
- Laboratório de Avaliação e Promoção da Saúde Ambiental, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz (Fiocruz), Rio de Janeiro 21040-900, RJ, Brazil
| | - Natalia Quinete
- Institute of Environment, Florida International University, North Miami, FL 33181, USA
- Department of Chemistry and Biochemistry, Florida International University, North Miami, FL 33181, USA
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7
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Lemos LS, Haxel JH, Olsen A, Burnett JD, Smith A, Chandler TE, Nieukirk SL, Larson SE, Hunt KE, Torres LG. Effects of vessel traffic and ocean noise on gray whale stress hormones. Sci Rep 2022; 12:18580. [PMID: 36329054 PMCID: PMC9633705 DOI: 10.1038/s41598-022-14510-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2021] [Accepted: 06/08/2022] [Indexed: 11/06/2022] Open
Abstract
Human use of marinescapes is rapidly increasing, especially in populated nearshore regions where recreational vessel traffic can be dense. Marine animals can have a physiological response to such elevated human activity that can impact individual health and population dynamics. To understand the physiological impacts of vessel traffic on baleen whales, we investigated the adrenal stress response of gray whales (Eschrichtius robustus) to variable vessel traffic levels through an assessment of fecal glucocorticoid metabolite (fGC) concentrations. This analysis was conducted at the individual level, at multiple temporal scales (1-7 days), and accounted for factors that may confound fGC: sex, age, nutritional status, and reproductive state. Data were collected in Oregon, USA, from June to October of 2016-2018. Results indicate significant correlations between fGC, month, and vessel counts from the day prior to fecal sample collection. Furthermore, we show a significant positive correlation between vessel traffic and underwater ambient noise levels, which indicates that noise produced by vessel traffic may be a causal factor for the increased fGC. This study increases knowledge of gray whale physiological response to vessel traffic and may inform management decisions regarding regulations of vessel traffic activities and thresholds near critical whale habitats.
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Affiliation(s)
- Leila S. Lemos
- grid.4391.f0000 0001 2112 1969Geospatial Ecology of Marine Megafauna Lab, Department of Fisheries, Wildlife, and Conservation Science, Marine Mammal Institute, Oregon State University, 2030 SE Marine Science Dr, Newport, OR 97365 USA ,grid.65456.340000 0001 2110 1845Institute of Environment, College of Arts, Science & Education, Florida International University, 3000 NE 151st St, North Miami, FL 33181 USA
| | - Joseph H. Haxel
- grid.451303.00000 0001 2218 3491Pacific Northwest National Laboratory, 1529 W Sequim Bay Rd, Sequim, WA 98382 USA ,grid.4391.f0000 0001 2112 1969Cooperative Institute for Marine Resources Studies, Oregon State University, 2030 SE Marine Science Dr, Newport, OR 97365 USA
| | - Amy Olsen
- grid.427422.50000 0000 9883 4476Conservation Programs and Partnerships, Seattle Aquarium, 1483 Alaskan Way Pier 59, Seattle, WA 98101 USA
| | - Jonathan D. Burnett
- grid.4391.f0000 0001 2112 1969Aerial Information Systems Laboratory, Forest Engineering, Resources and Management Department, Oregon State University, Oregon, USA
| | - Angela Smith
- grid.427422.50000 0000 9883 4476Conservation Programs and Partnerships, Seattle Aquarium, 1483 Alaskan Way Pier 59, Seattle, WA 98101 USA
| | - Todd E. Chandler
- grid.4391.f0000 0001 2112 1969Geospatial Ecology of Marine Megafauna Lab, Department of Fisheries, Wildlife, and Conservation Science, Marine Mammal Institute, Oregon State University, 2030 SE Marine Science Dr, Newport, OR 97365 USA
| | - Sharon L. Nieukirk
- grid.451303.00000 0001 2218 3491Pacific Northwest National Laboratory, 1529 W Sequim Bay Rd, Sequim, WA 98382 USA
| | - Shawn E. Larson
- grid.427422.50000 0000 9883 4476Conservation Programs and Partnerships, Seattle Aquarium, 1483 Alaskan Way Pier 59, Seattle, WA 98101 USA
| | - Kathleen E. Hunt
- grid.22448.380000 0004 1936 8032Department of Biology, Smithsonian-Mason School of Conservation, George Mason University, Fairfax, VA USA
| | - Leigh G. Torres
- grid.4391.f0000 0001 2112 1969Geospatial Ecology of Marine Megafauna Lab, Department of Fisheries, Wildlife, and Conservation Science, Marine Mammal Institute, Oregon State University, 2030 SE Marine Science Dr, Newport, OR 97365 USA
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Melica V, Atkinson S, Calambokidis J, Gendron D, Lang A, Scordino J. Naturally stressed? Glucocorticoid profiles in blubber of blue and gray whales in response to life history parameters. MARINE MAMMAL SCIENCE 2022; 38:1524-1548. [PMID: 36619002 PMCID: PMC9815209 DOI: 10.1111/mms.12954] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/17/2023]
Abstract
The goal of the present study was to carry out a thorough methodological validation and describe baseline profiles for glucocorticoid hormones (cortisol and corticosterone) in blubber from blue (n = 77) and gray (n = 103) whales from the eastern North Pacific Ocean. For each species, we modelled cortisol and corticosterone concentrations in response to life history parameters (age, sex, reproductive status) and season or geographic location. In blue whales, cortisol concentrations did not vary significantly by age class, sex, or reproductive status, whereas corticosterone was significantly lower in immature than in adult females (p < .001). In gray whales, cortisol concentrations were significantly higher in lactating whales (p < .05), while corticosterone was significantly different between females and males (p = .001) and elevated in calves (p = .003). In gray whales, corticosterone concentrations were significantly lower in males sampled later in the year (August to November) compared to both sexes sampled between March and August (p = .05), but no seasonal trend occurred in blue whales. Our results indicate that glucocorticoid actions vary between species and sex in large whales. Analysis of multiple hormones improves our understanding of the physiology of maintaining metabolic homeostasis or coping with chronic stressors.
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Affiliation(s)
- Valentina Melica
- Fisheries Department, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, Alaska
| | - Shannon Atkinson
- Fisheries Department, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, Alaska
| | | | - Diane Gendron
- Instituto Politecnico Nacional, Centro Interdisciplinario de Ciencias Marina (IPN-CICIMAR), La Paz, Baja California Sur, Mexico
| | - Aimee Lang
- Ocean Associates Inc., on contract to NOAA Southwest Fisheries Science Center, La Jolla, California
| | - Jonathan Scordino
- Marine Mammal Program, Makah Fisheries Management, Neah Bay, Washington
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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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Fernández Ajó A, Hunt KE, Dillon D, Uhart M, Sironi M, Rowntree V, Loren Buck C. Optimizing hormone extraction protocols for whale baleen: Tackling questions of solvent:sample ratio and variation. Gen Comp Endocrinol 2022; 315:113828. [PMID: 34058189 DOI: 10.1016/j.ygcen.2021.113828] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/07/2021] [Accepted: 05/25/2021] [Indexed: 12/19/2022]
Abstract
Obtaining endocrine data from alternative sample types such as baleen and other keratinized tissues has proven a valuable tool to investigate reproductive and stress physiology via steroid hormone quantification, and metabolic stress via thyroid hormone quantification in whales and other vertebrates. These alternative sample types provide an integrated measure of plasma levels over the period that the structure was growing, thus capturing months or even years of an individual's endocrine history. Additionally, their robust and stable keratin matrix allows such samples to be stored for years to decades, enabling the analysis and comparison of endocrine patterns from past and modern populations. However, the extraction and analysis of hormones from baleen and other keratinized tissues remains novel and requires both biological and analytical validations to ensure the method fulfills the requirements for its intended use. We utilized baleen recovered at necropsy from southern right whales (Eubalaena australis) that died at Península Valdés, Argentina, using a commercially available progesterone enzyme immunoassay (EIA) to address two methodological questions: 1) what is the minimum sample mass required to reliably quantify hormone content of baleen samples analyzed with commercially available EIAs, and 2) what is the optimal ratio of solvent volume to sample mass, i.e., the ratio that yields the maximum amount of hormone with high accuracy and low variability between replicates. We concluded that masses of at least 20 mg should be used whenever possible, and extraction is best performed using an 80:1 ratio of solvent to sample (volume of solvent to sample mass; μl:mg). These results can help researchers to make informed methodological decisions when using a destructive extraction method with rare or unique specimens.
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Affiliation(s)
- Alejandro Fernández Ajó
- Department of Biological Sciences, Northern Arizona University, 617 S. Beaver St., PO Box 5640, Flagstaff, AZ 86011, USA; Instituto de Conservación de Ballenas, Capital Federal, O'Higgins 4380, Ciudad Autónoma de Buenos Aires 1429, Argentina.
| | - Kathleen E Hunt
- George Mason University & Smithsonian-Mason School of Conservation, 1500 Remount Rd, Front Royal, VA 22630, USA
| | - Danielle Dillon
- Department of Biological Sciences, Northern Arizona University, 617 S. Beaver St., PO Box 5640, Flagstaff, AZ 86011, USA
| | - Marcela Uhart
- Southern Right Whale Health Monitoring Program, Los Alerces 3376, Puerto Madryn, Chubut 9120, Argentina; Wildlife Health Center, School of Veterinary Medicine, University of California, 1089 Veterinary Medicine Drive, VM3B Ground Floor, Davis, CA 95616, USA
| | - Mariano Sironi
- Instituto de Conservación de Ballenas, Capital Federal, O'Higgins 4380, Ciudad Autónoma de Buenos Aires 1429, Argentina; Facultad de Ciencias Exactas, Físicas y Naturales (FCEFyN), Universidad Nacional de Córdoba, Av. Vélez Sársfield 299, Córdoba 5000, Argentina
| | - Victoria Rowntree
- Instituto de Conservación de Ballenas, Capital Federal, O'Higgins 4380, Ciudad Autónoma de Buenos Aires 1429, Argentina; Wildlife Health Center, School of Veterinary Medicine, University of California, 1089 Veterinary Medicine Drive, VM3B Ground Floor, Davis, CA 95616, USA; Department of Biology, University of Utah, 257 South 1400 East University of Utah, Salt Lake City, UT 84112, USA; Ocean Alliance/Whale Conservation Institute, 32 Horton St, Gloucester, MA 01930, USA
| | - C Loren Buck
- Department of Biological Sciences, Northern Arizona University, 617 S. Beaver St., PO Box 5640, Flagstaff, AZ 86011, USA
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11
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Potential endocrine correlation with exposure to domoic acid in Southern Right Whale (Eubalaena australis) at the Península Valdés breeding ground. Oecologia 2021; 198:21-34. [PMID: 34800166 DOI: 10.1007/s00442-021-05078-4] [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: 03/15/2021] [Accepted: 11/07/2021] [Indexed: 10/19/2022]
Abstract
In waters off Península Valdés (PV), Argentina, southern right whales (SRW, Eubalaena australis) are occasionally exposed to domoic acid (DA), a neurotoxin produced by diatoms of the genus Pseudo-nitzschia. Domoic acid toxicity in marine mammals can cause gastrointestinal and neurological clinical signs, alterations in hematologic and endocrine variables, and can be fatal in extreme cases. In this study, we validated an enzyme immunoassay to quantify fecal glucocorticoid metabolites (fGCm) in 16 SRW fecal samples from live and dead stranded whales in PV from 2013 to 2018 and assessed fGCm levels associated with DA exposure. Overall, fGCm levels were significantly lower in SRWs with detectable fecal DA (n = 3) as compared to SRWs with undetectable fecal DA levels (n = 13). The highest fecal DA was observed in a live lactating female, which had low fGCm compared to the other lactating females studied. The highest fGCm was observed in a lactating female with undetectable DA; interestingly, at the time of sample collection, this female was sighted with two calves, an extremely unusual occurrence in this species. Though the sample size of these exceptionally rare breeding-season fecal samples was unavoidably small, our study provides evidence of potential adrenal alterations in whales exposed to an environmental neurotoxin such as DA.
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12
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Comizzoli P, Holt WV. Recent Progress in Spermatology Contributing to the Knowledge and Conservation of Rare and Endangered Species. Annu Rev Anim Biosci 2021; 10:469-490. [PMID: 34758275 DOI: 10.1146/annurev-animal-020420-040600] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
There is a remarkable diversity in the animal kingdom regarding mechanisms underlying the production, maturation, structure, and function of sperm cells. Spermatology studies contribute to the knowledge of species diversity and also provide information about individual or population fitness. Furthermore, this fundamental research is required before collected spermatozoa can be used for conservation breeding, including assisted reproduction and cryobanking. This article aims to (a) review the most recent knowledge on sperm morphology and function in wild animal species, (b) analyze how this knowledge can be used to save species in their natural habitat or ex situ, and (c) propose future scientific directions in wildlife spermatology that could positively impact animal conservation. Variations in sperm structure and performance within and between species have multiple origins and significance. This collective body of knowledge enables the design and implementation of conservation strategies and action plans that integrate several disciplines. Expected final online publication date for the Annual Review of Animal Biosciences, Volume 10 is February 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- Pierre Comizzoli
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, USA;
| | - William V Holt
- Academic Unit of Reproductive and Developmental Medicine, University of Sheffield, United Kingdom;
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13
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Dalle Luche G, Boggs ASP, Kucklick JR, Hawker DW, Wisse JH, Bengtson Nash S. Steroid hormone profiles and body conditions of migrating male humpback whales (Megaptera novaeangliae). Gen Comp Endocrinol 2021; 313:113888. [PMID: 34425085 DOI: 10.1016/j.ygcen.2021.113888] [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: 12/02/2020] [Revised: 08/08/2021] [Accepted: 08/18/2021] [Indexed: 11/21/2022]
Abstract
Simultaneous analysis of multiple steroid hormones from remotely obtained blubber biopsies has the potential to concurrently provide information regarding stress and reproductive status from free-swimming cetaceans, while also investigating correlations between hormone concentrations and other health biomarkers. In this study we measured blubber concentration profiles of eight reproductive and adrenal steroid hormones (17α-hydroxy-progesterone, testosterone, androstenedione, progesterone, cortisol, 11-deoxy-corticosterone, oestrone, and oestradiol) together with body condition, as determined by the inverse Adipocyte Index, of 101 male humpback whales. Whales were sampled randomly at two time points, while migrating to and from their northeast Australian breeding grounds, allowing for intra- and inter-seasonal profile analysis. Testosterone, progesterone and cortisol together with androstenedione 17α-hydroxyprogesterone, and oestrone concentrations (the latter quantified for the first time in live biopsied male humpback whales) decreased between the northward and southward migrations. Decreasing testosterone levels during the height of humpback whale conceptions suggests asynchronicity between blubber testosterone levels and the expected peak of male fertility. Statistically significant relationships between levels of certain steroid analytes were observed and appeared to change between the early and late breeding seasons. During the northward migration, testosterone, progesterone, androstenedione, oestrone and 17α-hydroxyprogesterone levels were positively correlated. Cortisol concentrations correlated positively with those of testosterone during the northward migration, but negatively during the southward migration. Androstenedione and testosterone were positively correlated with adiposity during the late breeding season. These hormone-hormone and hormone-adiposity correlations may be reflective of the activation of certain steroid hormone synthesis pathways, or alternatively, of concomitant physiological stimuli. As steroid hormones work in concert, information on multiple steroid hormones is needed to interpret endocrinological status and understand the relationships between these compounds and ancillary health markers. This study provides steroid hormone profiles of wild male humpback whales, as well as the first insight into seasonal male endocrinology as a function of adiposity.
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Affiliation(s)
- Greta Dalle Luche
- Environmental Futures Research Institute, Griffith University, Brisbane, QLD 4111, Australia.
| | - Ashley S P Boggs
- National Institute of Standards and Technology, Hollings Marine Laboratory, Charleston, SC 29412, USA
| | - John R Kucklick
- National Institute of Standards and Technology, Hollings Marine Laboratory, Charleston, SC 29412, USA
| | - Darryl W Hawker
- School of Environment and Science, Griffith University, Brisbane, QLD 4111, Australia
| | - Jillian H Wisse
- Nicholas School of the Environment, Duke University, Durham, NC 27710, USA
| | - Susan Bengtson Nash
- Environmental Futures Research Institute, Griffith University, Brisbane, QLD 4111, Australia
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14
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Holt WV, Comizzoli P. Opportunities and Limitations for Reproductive Science in Species Conservation. Annu Rev Anim Biosci 2021; 10:491-511. [PMID: 34699258 DOI: 10.1146/annurev-animal-013120-030858] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Reproductive science in the context of conservation biology is often understood solely in terms of breeding threatened species. Although technologies developed primarily for agriculture or biomedicine have a potentially important role in species conservation, their effectiveness is limited if we regard the main objective of animal conservation as helping to support populations rather than to breed a small number of individuals. The global threats facing wild species include the consequences of climate change, population growth, urbanization, atmospheric and water pollution, and the release of chemicals into the environment, to cite but a few. Reproductive sciences provide important and often unexpected windows into many of these consequences, and our aim here is both to demonstrate the breadth of reproductive science and the importance of basic knowledge and to suggest where some of the insights might be useful in mitigating the problems. Expected final online publication date for the Annual Review of Animal Biosciences, Volume 10 is February 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.
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Affiliation(s)
- William V Holt
- Academic Unit of Reproductive and Developmental Medicine, Department of Oncology & Metabolism, University of Sheffield, Sheffield, United Kingdom;
| | - Pierre Comizzoli
- Smithsonian Conservation Biology Institute, National Zoological Park, Washington, DC, USA;
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15
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Melica V, Atkinson S, Calambokidis J, Lang A, Scordino J, Mueter F. Application of endocrine biomarkers to update information on reproductive physiology in gray whale (Eschrichtius robustus). PLoS One 2021; 16:e0255368. [PMID: 34343192 PMCID: PMC8330940 DOI: 10.1371/journal.pone.0255368] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2021] [Accepted: 07/14/2021] [Indexed: 11/18/2022] Open
Abstract
Most of our knowledge on reproductive biology of gray whales dates back to scientific research conducted during commercial whaling in the late 1950s and 1960s. The goal of the present study was to provide updated insights on reproductive physiology of gray whales, using progesterone and testosterone as biomarkers. We measured hormone concentrations using enzyme immunoassay (EIA) techniques in blubber biopsies collected from 106 individual whales from March to November over a span of 12 years (2004-2016) between California and Alaska. We found testosterone concentrations in males to increase significantly with age (P = 0.03). Adult males showed significantly elevated testosterone concentrations when sampled in the fall compared to the summer (P = 0.01), likely indicating physiological preparation for mating. We measured testosterone concentrations in females of different age classes, but no statistical differences were found. We found significantly higher progesterone concentrations in pregnant females compared to non-pregnant females and adult males (P< 0.001), indicating progesterone is a valid biomarker for pregnancy in gray whales. Both female and male calves had elevated progesterone concentrations, suggesting maternal transfer via lactation. We fit a mixture of two normal distributions to progesterone data from all non-calf females to identify clusters of high and low progesterone and estimated the probability of being pregnant for whales of unknown reproductive status. With this approach we identified likely pregnant and non-pregnant animals. This study represents an important milestone on reproductive profiles in this population, that can be used to estimate more accurate and precise reproductive parameters to be used for better understanding population dynamics of gray whales.
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Affiliation(s)
- Valentina Melica
- Fisheries Department, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, Alaska, United States of America
- * E-mail:
| | - Shannon Atkinson
- Fisheries Department, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, Alaska, United States of America
| | | | - Aimée Lang
- Ocean Associates Inc., on Contract to NOAA Southwest Fisheries Science Center, La Jolla, California, United States of America
| | - Jonathan Scordino
- Marine Mammal Program, Makah Fisheries Management, Neah Bay, Washington, United States of America
| | - Franz Mueter
- Fisheries Department, College of Fisheries and Ocean Sciences, University of Alaska Fairbanks, Juneau, Alaska, United States of America
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16
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Christianson D, Coleman TH, Doan Q, Haroldson MA. Physiological consequences of consuming low-energy foods: herbivory coincides with a stress response in Yellowstone bears. CONSERVATION PHYSIOLOGY 2021; 9:coab029. [PMID: 34345432 PMCID: PMC8325456 DOI: 10.1093/conphys/coab029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/25/2021] [Accepted: 04/08/2021] [Indexed: 06/13/2023]
Abstract
Meat, fruit, seeds and other high-energy bear foods are often highly localized and briefly available and understanding which factors influence bear consumption of these foods is a common focus of bear conservation and ecology. However, the most common bear foods, graminoids and forbs, are more widespread but of lower quality. We poorly understand how herbage consumption impacts bear physiology, such as endocrine system function that regulates homeostasis and stress responses. Here, we described bear diets with a novel approach, measuring the concentration of chlorophyll in bear scats (faecal chlorophyll) to index the proportion of the recent diet that was composed of leaves from graminoids and forbs. We measured faecal chlorophyll and faecal cortisol in 351 grizzly (Ursus arctos, n = 255) and black bear (Ursus americanus, n = 96) scats from Yellowstone National Park in 2008-2009. We compared models of faecal chlorophyll and faecal cortisol concentrations considering the effects of spatial, dietary, scat and bear-specific factors including species. Faecal chlorophyll levels were the strongest predictor of faecal cortisol in a manner that suggested an endocrine response to a low-energy diet. Both compounds were highest during the spring and early summer months, overlapping the breeding season when higher energy foods were less available. Effects of scat composition, scat weathering, bear age, bear sex, species and other factors that have previously been shown to influence faecal cortisol in bears were not important unless faecal chlorophyll was excluded from models. The top models of faecal chlorophyll suggested grazing was primarily influenced by spatial attributes, with greater grazing closer to recreational trails, implying that elevated cortisol with grazing could be a response to anthropogenic activity. Our results confirm that higher stress hormone concentrations correspond with lower quality diets in bears, particularly grazing, and that faecal chlorophyll shows promise as a metric for studying grazing behaviour and its consequences.
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Affiliation(s)
- David Christianson
- Department of Ecosystem Science and Management, University of Wyoming, Laramie, WY 82071, USA
| | - Tyler H Coleman
- Sequoia-Kings Canyon National Park, National Park Service, 47050 Generals Highway, Three Rivers, CA 93271, USA
| | - Quint Doan
- School of Forestry and Environmental Studies, Yale University, 370 Prospect Street, New Haven CT 06511, USA
| | - Mark A Haroldson
- U.S. Geological Survey, Northern Rocky Mountain Science Center, Interagency Grizzly Bear Study Team, 2327 University Way, Suite 2, Bozeman, MT 59717, USA
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