1
|
Gonzalez-Astudillo V, Schaffer-White A, Noble L, O’Hara P, Murray P, Barnes TS, Allavena R. Spontaneous Lesions of Endangered Geriatric Julia Creek Dunnarts ( Sminthopsis douglasi, Archer 1979) with Emphasis in Reproductive Pathology. Vet Sci 2024; 11:142. [PMID: 38668410 PMCID: PMC11054575 DOI: 10.3390/vetsci11040142] [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: 12/31/2023] [Revised: 02/22/2024] [Accepted: 03/13/2024] [Indexed: 04/29/2024] Open
Abstract
Julia Creek dunnarts are an endangered species of carnivorous marsupials and the focus of multiple conservation strategies involving significant resources such as captive breeding programs. Despite the relevance for conservation, no study to date has focused on evaluating geriatric diseases in dunnarts. This study describes the pathology findings in a group of one wild and thirty-five captive-born, mostly geriatric Julia Creek dunnarts that failed to produce offspring over multiple breeding periods. A total of 20 females and 16 males were submitted for a postmortem examination, with ages ranging from 9 to 42 and 12 to 42 months for females and males, respectively. Of these, 10 had unremarkable findings. The most common condition in females was cystic glandular hyperplasia (n = 8), typical of hormonal dysregulation profiles in senescence, particularly hyperestrogenism. Rarely, cutaneous disease represented by unidentified dermal round cell infiltrates was observed in females (n = 2). Primary reproductive hormonal dysregulation was also suspected in males diagnosed with testicular degeneration, aspermatogenesis and/or atrophy (n = 3). Cutaneous round cell infiltrates, possibly compatible with epitheliotropic lymphomas, were seen in males (n = 3), and 2/3 affected males also had concurrent testicular degeneration or atrophy, indicating male sex could be a predictor for lymphoid neoplasia in aged dunnarts, especially in individuals with concurrent testosterone-luteinizing hormone dysregulation as it occurs in gonadectomized animals. The role of an underlying viral etiology is also explored. This study is the first to describe major spontaneous diseases in endangered aged Julia Creek dunnarts, providing an important understanding of senescence and geriatric diseases within a conservation context.
Collapse
Affiliation(s)
- Viviana Gonzalez-Astudillo
- School of Veterinary Science, The University of Queensland, Gatton Campus, Gatton, QLD 4343, Australia; (L.N.); (P.M.); (T.S.B.); (R.A.)
| | - Andrea Schaffer-White
- Independent Veterinary Pathology, 3245 Logan Road, Underwood, Brisbane, QLD 4119, Australia;
| | - Lawrence Noble
- School of Veterinary Science, The University of Queensland, Gatton Campus, Gatton, QLD 4343, Australia; (L.N.); (P.M.); (T.S.B.); (R.A.)
| | - Patricia O’Hara
- School of Agriculture and Food Sustainability, The University of Queensland, Gatton Campus, Gatton, QLD 4343, Australia;
| | - Peter Murray
- School of Veterinary Science, The University of Queensland, Gatton Campus, Gatton, QLD 4343, Australia; (L.N.); (P.M.); (T.S.B.); (R.A.)
- Biological Resources, The University of Queensland, Brisbane, QLD 4072, Australia
- School of Agriculture and Environmental Science, University of Southern Queensland, Toowoomba, QLD 4350, Australia
| | - Tamsin S. Barnes
- School of Veterinary Science, The University of Queensland, Gatton Campus, Gatton, QLD 4343, Australia; (L.N.); (P.M.); (T.S.B.); (R.A.)
| | - Rachel Allavena
- School of Veterinary Science, The University of Queensland, Gatton Campus, Gatton, QLD 4343, Australia; (L.N.); (P.M.); (T.S.B.); (R.A.)
| |
Collapse
|
2
|
Martínez L, de Andrés PJ, Caperos JM, Silván G, Fernández-Morán J, Casares M, Crespo B, Vélez D, Sanz L, Cáceres S, Illera JC. Predicting Sex in White Rhinoceroses: A Statistical Model for Conservation Management. Animals (Basel) 2023; 13:2583. [PMID: 37627374 PMCID: PMC10451157 DOI: 10.3390/ani13162583] [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: 05/30/2023] [Revised: 07/13/2023] [Accepted: 08/08/2023] [Indexed: 08/27/2023] Open
Abstract
Ensuring the effective management of every rhinoceros population is crucial for securing a future for the species, especially considering the escalating global threat of poaching and the challenges faced in captive breeding programs for this endangered species. Steroid hormones play pivotal roles in regulating diverse biological processes, making fecal hormonal determinations a valuable non-invasive tool for monitoring adrenal and gonadal endocrinologies and assessing reproductive status, particularly in endangered species. The purpose of this study was to develop a statistical model for predicting the sex of white rhinoceroses using hormonal determinations obtained from a single fecal sample. To achieve this, 562 fecal samples from 15 individuals of the Ceratotherium simum species were collected, and enzyme immunoassays were conducted to determine the concentrations of fecal cortisol, progesterone, estrone, and testosterone metabolites. The biological validation of the method provided an impressive accuracy rate of nearly 80% in predicting the sex of hypothetically unknown white rhinoceroses. Implementing this statistical model for sex identification in white rhinoceroses would yield significant benefits, including a better understanding of the structure and dynamics of wild populations. Additionally, it would enhance conservation management efforts aimed at protecting this endangered species. By utilizing this innovative approach, we can contribute to the preservation and long-term survival of white rhinoceros populations.
Collapse
Affiliation(s)
- Leticia Martínez
- Department of Animal Physiology, Veterinary Faculty, Complutense University of Madrid, 28040 Madrid, Spain
| | - Paloma Jimena de Andrés
- Department of Animal Medicine and Surgery, Veterinary Faculty, Complutense University of Madrid, 28040 Madrid, Spain
| | - Jose Manuel Caperos
- Clinical Psychology Unit (UNINPSI), Department of Psychology, Comillas Pontifical University, Calle Mateo Inurria 37, 28036 Madrid, Spain
| | - Gema Silván
- Department of Animal Physiology, Veterinary Faculty, Complutense University of Madrid, 28040 Madrid, Spain
| | | | - Miguel Casares
- Bioparc Valencia, Avenida Pio Baroja 3, 46015 Valencia, Spain
| | - Belén Crespo
- Department of Animal Physiology, Veterinary Faculty, Complutense University of Madrid, 28040 Madrid, Spain
| | - Daniel Vélez
- Department of Statistics and Operational Research, Faculty of Mathematics, Complutense University of Madrid, 28040 Madrid, Spain
| | - Luis Sanz
- Department of Statistics and Operational Research, Faculty of Mathematics, Complutense University of Madrid, 28040 Madrid, Spain
| | - Sara Cáceres
- Department of Animal Physiology, Veterinary Faculty, Complutense University of Madrid, 28040 Madrid, Spain
| | - Juan Carlos Illera
- Department of Animal Physiology, Veterinary Faculty, Complutense University of Madrid, 28040 Madrid, Spain
| |
Collapse
|
3
|
Flacke GL, Penfold LM, Schwarzenberger F, Martin GB, Rosales-Nieto CA, C J Paris M. Non-invasive Assessment of Fecal Glucocorticoid and Androgen Metabolites in the Pygmy Hippopotamus (Choeropsis liberiensis). Gen Comp Endocrinol 2023:114338. [PMID: 37348682 DOI: 10.1016/j.ygcen.2023.114338] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/24/2022] [Revised: 05/21/2023] [Accepted: 06/15/2023] [Indexed: 06/24/2023]
Abstract
The pygmy hippopotamus (Choeropsis liberiensis) is an endangered species endemic to the Upper Guinea Forest ecosystem in West Africa. We have limited information concerning the species' reproduction and well-being under managed care. We therefore developed non-invasive methods for characterizing gonadal androgen and adrenal hormone profiles in pygmy hippos using fecal samples collected from 12 males and 12 females housed in North American zoological institutions. We aimed to: 1) identify and validate enzyme immunoassays (EIAs) for measuring metabolites of corticosteroids and testosterone in feces; and 2) test whether gonadal activity is correlated with previous breeding history, season or type of housing. For glucocorticoids, several EIAs for measuring metabolites were investigated. A group-specific EIA exhibiting cross-reactivity with 11,17-dioxoandrostane (DOA) metabolites of cortisol most clearly reflected adrenocortical activity in response to ACTH1 challenge in both males and females. However, day-to-day concentrations of this metabolite in the feces of pygmy hippos that did not undergo ACTH challenge were near the detection limits of the assay, making this EIA impractical for assessing glucocorticoid activity in this species. Another group-specific EIA, exhibiting cross-reactivity with 5α-pregnane-3β,11β,21-triol-20-one, produced biologically relevant data and evidence of an appropriate response to pharmacological challenge with exogenous ACTH. The testosterone metabolite assay C196 (Arbor Assays, Ann Arbor, Michigan, USA) also produced biologically coherent data: adult males exhibited the highest mean androgen metabolite concentrations (477 ng/g), followed by adult females (259 ng/g) and juvenile males (160 ng/g). Proven breeding males had higher, but not significantly different, mean concentrations (472 ng/g) to unproven males (352 ng/g; P = 0.400). Similarly, adult males housed outdoors year-round in subtropical climates exhibited higher, but not statistically different mean concentrations (554 ng/g) to males in temperate climates that were housed indoors at least part of the year (412 ng/g; P = 0.208). There were, however, significant differences in mean concentrations among seasons for adult males, with higher values in spring (546 ng/g) and summer (542 ng/g) than in autumn (426 ng/g) and winter (388 ng/g, P = 0.003). In conclusion, we identified EIAs for the measurement of fecal metabolites of androgens and glucocorticoids that can be used for further studies to monitor gonadal activity in male pygmy hippos and adrenocortical activity in both sexes. We also identified a seasonal trend in male gonadal activity in this species under managed care in North America. Finally, our findings highlight an important consideration when using non-invasive methods for evaluating fecal cortisol metabolites: ACTH used for pharmacological validation of an EIA does not necessarily equate to biological relevance.
Collapse
Affiliation(s)
- Gabriella L Flacke
- UWA School of Agriculture and Environment, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia; Department of Animal Health, Zoo Miami, 12400 SW 152(nd) Street, Miami, Florida 33177, USA.
| | - Linda M Penfold
- South East Zoo Alliance for Reproduction & Conservation, 581705 White Oak Road, Yulee, FL 32097, USA.
| | - Franz Schwarzenberger
- Department of Biomedical Sciences - Endocrinology, University of Veterinary Medicine (Vetmeduni Vienna), Veterinärplatz 1, 1210 Vienna, Austria.
| | - Graeme B Martin
- UWA School of Agriculture and Environment, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
| | - César A Rosales-Nieto
- Department of Agricultural Sciences, Texas State University, 601 University Drive, San Marcos, Texas 78666, USA.
| | - Monique C J Paris
- Institute for Breeding Rare and Endangered African Mammals (IBREAM), Edinburgh EH3 6AT, United Kingdom; Mammal Research Institute and Centre for Neuroendocrinology, University of Pretoria, Department of Zoology and Entomology, Pretoria 0084, South Africa; College of Public Health, Veterinary and Medical Sciences, James Cook University, Townsville 4811, Australia.
| |
Collapse
|
4
|
Turner SE, Fedigan LM, Joyce MM, Matthews HD, Moriarity RJ, Nobuhara H, Nobuhara T, Stewart BM, Shimizu K. Mothers of disabled infants had higher cortisol levels in a free-ranging group of Japanese macaques (Macaca fuscata). Am J Primatol 2023:e23500. [PMID: 37189289 DOI: 10.1002/ajp.23500] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2022] [Revised: 04/15/2023] [Accepted: 04/29/2023] [Indexed: 05/17/2023]
Abstract
Glucocorticoids (GCs) are hormones released in response to stressors and can provide insight into an organism's physiological well-being. Experiencing chronic challenges to homeostasis is associated with significant deviations from baseline fecal GCs (fGCs) in many species, providing a noninvasive biomarker for assessing stress. In the group of free-ranging Japanese macaques (Macaca fuscata) at the Awajishima Monkey Center in Japan, ~17% have congenital limb malformations. We collected 646 fecal samples from 27 females over three consecutive birth seasons (May-August) and analyzed them using enzyme immunoassay to extract fGCs. We explored the relationship between fGC levels and individual (physical impairment and reproductive status), social (dominance rank and availability of kin for social support), and ecological variables (exposure to potential predators, rainfall, and wild fruit availability). A disabled infant was associated significantly with higher fGC in the mother; however, physical impairment in adult females was not significantly related to fGC levels. Females with higher dominance rank had significantly lower fGC levels than lower ranking females. Other factors did not relate significantly to fGC. These results suggest that providing care that meets the support needs of disabled infants poses a physiological challenge for mothers and suggests that physically impaired adults are able to effectively compensate for their disabilities with behavioral plasticity. Once an individual with congenital limb malformations survives infancy through their mother's care, physical impairment does not appear to influence fGC values, while social variables like dominance rank significantly influenced cortisol values in free-ranging female Japanese macaques.
Collapse
Affiliation(s)
- Sarah E Turner
- Department of Geography, Planning and Environment, Concordia University, Montreal, Quebec, Canada
| | - Linda M Fedigan
- Department of Anthropology and Archaeology, University of Calgary, Calgary, Alberta, Canada
| | - Megan M Joyce
- Department of Geography, Planning and Environment, Concordia University, Montreal, Quebec, Canada
| | - H Damon Matthews
- Department of Geography, Planning and Environment, Concordia University, Montreal, Quebec, Canada
| | - Robert J Moriarity
- School of Occupational and Public Health, Toronto Metropolitan University, Toronto, Ontario, Canada
| | | | | | - Brogan M Stewart
- Department of Geography, Planning and Environment, Concordia University, Montreal, Quebec, Canada
| | - Keiko Shimizu
- Department of Zoology, Faculty of Science, Okayama University of Science, Okayama, Japan
| |
Collapse
|
5
|
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.
Collapse
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
| |
Collapse
|
6
|
Donini V, Iacona E, Pedrotti L, Macho-Maschler S, Palme R, Corlatti L. Temporal stability of fecal cortisol metabolites in mountain-dwelling ungulates. Naturwissenschaften 2022; 109:20. [PMID: 35325316 PMCID: PMC8948117 DOI: 10.1007/s00114-022-01792-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 03/09/2022] [Accepted: 03/10/2022] [Indexed: 11/27/2022]
Abstract
Fecal cortisol metabolites (FCMs) are widely used to track stress responses in wildlife and captive species. Rules of thumb suggest that samples should be collected as soon as possible after defecation, to avoid decay of FCMs. To date, however, only a few studies investigated the stability of defecated FCMs over time, and most of them were conducted in controlled laboratory conditions. Here, we investigated the stability of FCMs over seven consecutive days, in two mountain-dwelling ungulates, under natural environmental conditions using a semi-experimental approach. Fecal samples from Northern chamois Rupicapra rupicapra (n = 24) and red deer Cervus elaphus (n = 22) were collected in summer of 2020 within the Stelvio National Park, Italy, and placed in an open area above 2000 m a.s.l. For the next 7 days, we collected a portion of each sample, and all sub-samples were analyzed with an 11-oxoetiocholanolone enzyme immunoassay. Exposure, temperature, and precipitation were fitted as covariates in non-linear generalized mixed models to assess FCM variation over time, and competing models were selected using AICc. For chamois, the best model included only time as a predictor, while for red deer, it included time, precipitation, and exposure. For both species, FCM values decreased rapidly from the first days after deposition until the fourth day. For red deer, in northern-exposed samples, FCM values decreased slower than in south-exposed ones; furthermore, FCM values increased with increasing precipitation. Our results offer a solid methodological basis to wildlife researchers and practitioners interested in the investigation of the ecological factors affecting stress variation in wildlife and support the recommendation to collect samples as fresh as possible, to avoid misleading inference. Further studies are necessary to evaluate the stability of FCMs when other enzyme immunoassays are used.
Collapse
Affiliation(s)
- Valerio Donini
- Stelvio National Park - ERSAF Lombardia, Via De Simoni 42, 23032, Bormio, Italy
| | - Elisa Iacona
- Stelvio National Park - ERSAF Lombardia, Via De Simoni 42, 23032, Bormio, Italy
| | - Luca Pedrotti
- Stelvio National Park - ERSAF Lombardia, Via De Simoni 42, 23032, Bormio, Italy
- Stelvio National Park - Autonomous Province of Trento, Via Roma 65, 38024, Cogolo di Peio, Italy
| | - Sabine Macho-Maschler
- Department of Biomedical Sciences, Unit of Physiology, Pathophysiology and Experimental Endocrinology, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Rupert Palme
- Department of Biomedical Sciences, Unit of Physiology, Pathophysiology and Experimental Endocrinology, University of Veterinary Medicine Vienna, Veterinärplatz 1, 1210, Vienna, Austria
| | - Luca Corlatti
- Stelvio National Park - ERSAF Lombardia, Via De Simoni 42, 23032, Bormio, Italy.
- Chair of Wildlife Ecology and Management, University of Freiburg, Tennenbacher Straße 4, 79106, Freiburg, Germany.
| |
Collapse
|
7
|
The Application of NIRS to Determine Animal Physiological Traits for Wildlife Management and Conservation. REMOTE SENSING 2021. [DOI: 10.3390/rs13183699] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The ability to measure and monitor wildlife populations is important for species management and conservation. The use of near-infrared spectroscopy (NIRS) to rapidly detect physiological traits from wildlife scat and other body materials could play an important role in the conservation of species. Previous research has demonstrated the potential for NIRS to detect diseases such as the novel COVID-19 from saliva, parasites from feces, and numerous other traits from animal skin, hair, and scat, such as cortisol metabolites, diet quality, sex, and reproductive status, that may be useful for population monitoring. Models developed from NIRS data use light reflected from a sample to relate the variation in the sample’s spectra to variation in a trait, which can then be used to predict that trait in unknown samples based on their spectra. The modelling process involves calibration, validation, and evaluation. Data sampling, pre-treatments, and the selection of training and testing datasets can impact model performance. We review the use of NIRS for measuring physiological traits in animals that may be useful for wildlife management and conservation and suggest future research to advance the application of NIRS for this purpose.
Collapse
|
8
|
Uchida K, Ng R, Vydro SA, Smith JE, Blumstein DT. The benefits of being dominant: health correlates of male social rank and age in a marmot. Curr Zool 2021; 68:19-26. [PMID: 35169626 PMCID: PMC8836331 DOI: 10.1093/cz/zoab034] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2021] [Accepted: 04/22/2021] [Indexed: 11/13/2022] Open
Abstract
Abstract
The benefits of dominance may not come without costs, particularly for males. For example, the “immunocompetence handicap hypothesis” states that males with enhanced mating success allocate resources to enhance reproductive output at a cost to their current health, whereas the “resource quality hypothesis” predicts that high-ranking males may benefit from increased reproduction and good health. Whereas the predictions from each have been well tested in captive animals and in a variety of highly social primates, fewer studies have been carried out in free-living, facultatively social animals. Using adult male yellow-bellied marmots (Marmota flaviventer), we evaluated predictions of these hypotheses by examining the relationship between social rank and 2 health indicators—fecal glucocorticoid metabolite (FCM) levels, and neutrophil/lymphocyte (N/L) ratios—after accounting for variation explained by age, body mass, and seasonality. We found that higher-ranking males tended to have a lower N/L ratio (reflecting good health) than lower-ranking individuals, whereas FCM levels were not significantly related to rank. In addition, heavier male marmots had lower N/L ratios, whereas body mass was not associated with FCM levels. We also found that older adult males had lower FCM levels (reflecting less physiological stress) but higher N/L ratios than younger adults. Finally, we found that FCM levels decreased as the active season progressed and FCM levels were associated with the time of the day. Overall, our results suggest that socially-dominant male marmots enjoyed better, not worse health in terms of lower N/L ratios.
Collapse
Affiliation(s)
- Kenta Uchida
- Department of Ecology & Evolutionary Biology, University of California, Los Angeles, CA 90095-1606, USA
| | - Rachel Ng
- Department of Ecology & Evolutionary Biology, University of California, Los Angeles, CA 90095-1606, USA
| | - Samuel A Vydro
- Department of Ecology & Evolutionary Biology, University of California, Los Angeles, CA 90095-1606, USA
| | - Jennifer E Smith
- Department of Ecology & Evolutionary Biology, University of California, Los Angeles, CA 90095-1606, USA
- Department of Biology, Mills College, Oakland, CA 94613, USA
| | - Daniel T Blumstein
- Department of Ecology & Evolutionary Biology, University of California, Los Angeles, CA 90095-1606, USA
- The Rocky Mountain Biological Laboratory, Crested Butte, CO 81224, USA
| |
Collapse
|
9
|
Pérez JM, Espinosa J, Boos M, Azorit C, Molina L, López-Montoya AJ. Evaluation of long-term 11-oxoaetiocholanolone stability in red deer faecal samples under different storage conditions. EUR J WILDLIFE RES 2020. [DOI: 10.1007/s10344-020-01399-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
10
|
Krone O, Bailey LD, Jähnig S, Lauth T, Dehnhard M. Monitoring corticoid metabolites in urine of white-tailed sea eagles: Negative effects of road proximity on breeding pairs. Gen Comp Endocrinol 2019; 283:113223. [PMID: 31323229 DOI: 10.1016/j.ygcen.2019.113223] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2018] [Revised: 05/15/2019] [Accepted: 07/15/2019] [Indexed: 11/30/2022]
Abstract
The white-tailed sea eagle (Haliaeetus albicilla) is known to be sensitive to disturbance. To better understand potential stressors, we measured corticosterone metabolite levels in H. albicilla excreta and recorded the nest success of breeding pairs. We tested the ability of four enzyme immunoassays (EIA) to measure urinary glucocorticoid metabolites (uGM) in the excreta of one adult female eagle subjected to a controlled physiological stress treatment. We identified corticosterone-21-HS to be the most sensitive EIA to changes in uGM concentration. To exclude a sex bias, we confirmed the assay's applicability with samples collected from similar stress treatments in two juvenile males. We used the identified EIA to measure uGM in wild breeding pairs and tested effects of disturbance. Breeding pairs nesting closer to roads and paths had higher uGM concentrations (p = 0.02), which is likely an effect of human recreational activity and disturbance. There was no difference in uGM concentrations between failed and successful nests. Our results highlight the potential impact of road and path proximity on white-tailed sea eagles, with potential importance for species management and conservation, particularly with respect to nest protection zone legislation.
Collapse
Affiliation(s)
- Oliver Krone
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany.
| | - Liam D Bailey
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany
| | - Susanne Jähnig
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany
| | | | - Martin Dehnhard
- Leibniz Institute for Zoo and Wildlife Research, Alfred-Kowalke-Strasse 17, 10315 Berlin, Germany
| |
Collapse
|
11
|
Dulude-de Broin F, Côté SD, Whiteside DP, Mastromonaco GF. Faecal metabolites and hair cortisol as biological markers of HPA-axis activity in the Rocky mountain goat. Gen Comp Endocrinol 2019; 280:147-157. [PMID: 31009603 DOI: 10.1016/j.ygcen.2019.04.022] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/16/2018] [Revised: 04/04/2019] [Accepted: 04/19/2019] [Indexed: 11/27/2022]
Abstract
Monitoring glucocorticoids in faeces and hair is increasingly used in ecological studies and provides a powerful and minimally intrusive mean to identify physiological challenges faced by wild animals. Using a cortisol and a corticosterone immunoassays, we conducted an adrenocorticotropic (ACTH) challenge with five weekly repeated injections to validate the use of faecal glucocorticoid metabolites and hair cortisol concentration as biological markers of the HPA-axis activity in captive mountain goats (Oreamnos americanus). We also investigated the effect of endogenous (age, sex, reproductive status) and methodological (faecal sample collection date, freezing delay and hair type) variables on cortisol values using faecal and hair samples collected from marked wild mountain goats during a long-term study. The cortisol enzyme immunoassay was reliable for mountain goat faeces and hair, and was sensitive enough to detect a clear rise in glucocorticoid concentration following ACTH injections for both matrices. Age and sex had no detectable effect on faecal glucocorticoid metabolites, but hair cortisol concentration was higher in kids and yearlings than in older goats, and lower in adult males compared to adult females. Reproductive status had no detectable effect on both faecal and hair measurements. Faecal metabolite concentrations increased with sample collection date in late spring until mid-summer and decreased afterward until early fall. Guard hair had nearly twice as much cortisol per gram as undercoat hair. Prolonged delay to freezing reduced the concentration of faecal glucocorticoid metabolites, but degradation seemed limited when samples were exposed to wind and sun or when ambient temperature was low. We conclude that faeces and hair can be used as valid biomarkers of the HPA-axis activity in mountain goat provided that confounding variables are taken into account when interpreting measurements.
Collapse
Affiliation(s)
- Frédéric Dulude-de Broin
- Département de biologie, and Centre d'études Nordiques, Université Laval, Québec G1V 0A6, Canada.
| | - Steeve D Côté
- Département de biologie, and Centre d'études Nordiques, Université Laval, Québec G1V 0A6, Canada
| | - Douglas P Whiteside
- Department of Ecosystem and Public Health, Faculty of Veterinary Medicine, University of Calgary, Alberta T2N 4Z6, Canada; Calgary Zoo, Alberta T2E 7V6, Canada
| | - Gabriela F Mastromonaco
- Reproductive Physiology, Toronto Zoo, 361A Old Finch Avenue, Toronto, Ontario, M1B 5K7, Canada
| |
Collapse
|
12
|
Davidson NB, Koch NI, Sarsby J, Jones E, Hurst JL, Beynon RJ. Rapid identification of species, sex and maturity by mass spectrometric analysis of animal faeces. BMC Biol 2019; 17:66. [PMID: 31412863 PMCID: PMC6693146 DOI: 10.1186/s12915-019-0686-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2019] [Accepted: 07/26/2019] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND We describe a new approach to the recovery of information from faecal samples, based on the analysis of the molecular signature generated by rapid evaporative ionisation mass spectrometry (REIMS). RESULTS Faecal pellets from five different rodent species were analysed by REIMS, and complex mass spectra were acquired rapidly (typically a few seconds per sample). The uninterpreted mass spectra (signatures) were then used to seed linear discriminant analysis and classification models based on random forests. It was possible to classify each species of origin with a high rate of accuracy, whether faeces were from animals maintained under standard laboratory conditions or wild-caught. REIMS signatures were stable to prior storage of the faecal material under a range of different conditions and were not altered rapidly or radically by changes in diet. Further, within species, REIMS signatures could be used to discriminate faeces from adult versus juvenile mice, male versus female mice and those from three different laboratory strains. CONCLUSIONS REIMS offers a completely novel method for the rapid analysis of faecal samples, extending faecal analysis (previously focused on DNA) to an assessment of phenotype, and has considerable potential as a new tool in the armamentarium of the field biologist.
Collapse
Affiliation(s)
- Nicola B Davidson
- Mammalian Behaviour and Evolution Group, Institute of Integrative Biology, University of Liverpool, Leahurst Campus, Neston, CH64 7TE, UK
| | - Natalie I Koch
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Joscelyn Sarsby
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Emrys Jones
- Waters Corporation, Stamford Avenue, Altrincham Road, Wilmslow, SK9 4AX, UK
| | - Jane L Hurst
- Mammalian Behaviour and Evolution Group, Institute of Integrative Biology, University of Liverpool, Leahurst Campus, Neston, CH64 7TE, UK.
| | - Robert J Beynon
- Centre for Proteome Research, Institute of Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK.
| |
Collapse
|
13
|
|
14
|
Tyagi A, Kumar V, Kittur S, Reddy M, Naidenko S, Ganswindt A, Umapathy G. Physiological stress responses of tigers due to anthropogenic disturbance especially tourism in two central Indian tiger reserves. CONSERVATION PHYSIOLOGY 2019; 7:coz045. [PMID: 31321036 PMCID: PMC6626984 DOI: 10.1093/conphys/coz045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2019] [Revised: 05/31/2019] [Accepted: 06/17/2019] [Indexed: 05/10/2023]
Abstract
Tigers continue to face unprecedented threats to their existence due to poaching, habitat loss, habitat fragmentation and anthropogenic disturbances. The present study examines the physiological stress response of tigers due to anthropogenic activities including wildlife tourism in Bandhavgarh Tiger Reserve and Kanha Tiger Reserve using faecal glucocorticoid metabolite (fGCM) measurement. We collected a total of 341 faecal samples from both reserves during tourism and non-tourism periods. Data on various anthropogenic disturbances including tourism activities like number of vehicles and visitors were also collected. We ascertained the species identity and sex of all the samples collected using genetic markers. fGCMs were extracted using a previously reported procedure, and fGCM concentrations were subsequently determined using an established enzyme immunoassay. There was no significant difference in overall mean fGCM concentrations between the two tiger reserves, but within each reserve, concentrations were significantly higher in tigers during the tourism period as compared to the non-tourism period. We also found that the number of tourist vehicles and disturbance level significantly correlated with fGCM concentrations. This study further supports the assumption that unbridled tourism associated with high anthropogenic disturbance can be related to perceived stress and consequently may have an impact on the reproductive fitness of tigers and long-term survival of isolated populations.
Collapse
Affiliation(s)
- Abhinav Tyagi
- Laboratory for the Conservation of Endangered Species, Council for Scientific and Industrial Research—Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, Telangana, India
| | - Vinod Kumar
- Laboratory for the Conservation of Endangered Species, Council for Scientific and Industrial Research—Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, Telangana, India
| | - Sagar Kittur
- Laboratory for the Conservation of Endangered Species, Council for Scientific and Industrial Research—Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, Telangana, India
| | - Mahender Reddy
- Laboratory for the Conservation of Endangered Species, Council for Scientific and Industrial Research—Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, Telangana, India
| | - Sergey Naidenko
- A.N. Severtsov Institute of Ecology and Evolution, Leninsky, pr. 33, Moscow, Russia
| | - Andre Ganswindt
- Mammal Research Institute, Faculty of Natural and Agricultural Sciences, University of Pretoria, Private Bag X20, Hatfield, South Africa
| | - Govindhaswamy Umapathy
- Laboratory for the Conservation of Endangered Species, Council for Scientific and Industrial Research—Centre for Cellular and Molecular Biology, Uppal Road, Hyderabad, Telangana, India
| |
Collapse
|
15
|
|
16
|
Fattorini N, Brunetti C, Baruzzi C, Macchi E, Pagliarella MC, Pallari N, Lovari S, Ferretti F. Being “hangry”: food depletion and its cascading effects on social behaviour. Biol J Linn Soc Lond 2018. [DOI: 10.1093/biolinnean/bly119] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Niccolò Fattorini
- Department of Life Sciences, University of Siena, Via P.A. Mattioli, Siena, Italy
| | - Claudia Brunetti
- Department of Life Sciences, University of Siena, Via P.A. Mattioli, Siena, Italy
| | - Carolina Baruzzi
- Department of Life Sciences, University of Siena, Via P.A. Mattioli, Siena, Italy
| | - Elisabetta Macchi
- Department of Veterinary Sciences, University of Torino, Via L. Da Vinci, Grugliasco (TO), Italy
| | - Maria Chiara Pagliarella
- Department of Bioscience and Territory, University of Molise, Via F. De Sanctis, Campobasso, Italy
| | - Noemi Pallari
- Department of Life Sciences, University of Siena, Via P.A. Mattioli, Siena, Italy
| | - Sandro Lovari
- Department of Life Sciences, University of Siena, Via P.A. Mattioli, Siena, Italy
- Maremma Natural History Museum, Strada Corsini, Grosseto, Italy
| | - Francesco Ferretti
- Department of Life Sciences, University of Siena, Via P.A. Mattioli, Siena, Italy
| |
Collapse
|
17
|
Molina‐García L, Pérez JM, Sarasa M, Ureña‐Gutiérrez B, Espinosa J, Azorit C. HPLC-QTOF method for quantifying 11-ketoetiocholanolone, a cortisol metabolite, in ruminants' feces: Optimization and validation. Ecol Evol 2018; 8:9218-9228. [PMID: 30377495 PMCID: PMC6194299 DOI: 10.1002/ece3.4285] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2017] [Revised: 04/23/2018] [Accepted: 05/19/2018] [Indexed: 11/26/2022] Open
Abstract
Studies of animal ecology can benefit from a quantified understanding of eco-physiological processes and, in particular, of the physiological responses in free-ranging animals to potential stressors. The determination of fecal cortisol metabolites as a noninvasive method for monitoring stress has proved to be a powerful tool. High-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) has emerged as the most accurate method for avoiding problems related to the nonspecificity of immunoassays. In this study, we optimize and validate a reliable method using HPLC-MS/MS for quantifying 11-ketoetiocholanolone (11-k), a representative fecal cortisol metabolite in ruminants. An appropriate extraction and purification procedure was developed taking into account the complex nature of feces. The final extract obtained was then analyzed with HPLC-MS/MS using a quadrupole-time-of-fly (QTOF) tandem mass spectrometer with an electrospray ionization interface operating in positive mode, which allowed an unequivocal determination of the metabolite due to its accurate mass capabilities. After rigorous optimization of both sample extraction and the HPLC-QTOF parameters, making use of feces from free-ranging Iberian ibex, ideal conditions were established. Matrix-matched standards were used to calibrate the method. The limit of detection and quantification was 13- and 40- ng/g, respectively. The validation of the method was performed with recoveries in the range of 85-110%, a figure much higher than the 60% obtained with the previous extraction methods used in our laboratory, and with relative standard deviations (RSDs) no higher than 15% for the complete analytical procedure, including extraction and analysis. The time required for the fecal 11-k analysis was greatly reduced in comparison with the previous work carried out in our laboratory. This is the first time that QTOF mass detection coupled with HPLC has been validated for 11-k quantification in feces from free-ranging ruminants such as Iberian ibex. Given the high selectivity and sensitivity attained, our method could become a useful tool for noninvasive stress quantification in ruminants.
Collapse
Affiliation(s)
- Lucía Molina‐García
- Department of Animal and Plant Biology, and EcologyUniversity of JaénJaénSpain
| | - Jesus M. Pérez
- Department of Animal and Plant Biology, and EcologyUniversity of JaénJaénSpain
| | - Mathieu Sarasa
- Fédération Nationale des Chasseurs (FNC)Issy‐les‐MoulineauxFrance
- Present address:
BEOPSToulouseFrance
| | | | - Jose Espinosa
- Department of Animal and Plant Biology, and EcologyUniversity of JaénJaénSpain
| | - Concepción Azorit
- Department of Animal and Plant Biology, and EcologyUniversity of JaénJaénSpain
| |
Collapse
|
18
|
Coppes J, Kämmerle JL, Willert M, Kohnen A, Palme R, Braunisch V. The importance of individual heterogeneity for interpreting faecal glucocorticoid metabolite levels in wildlife studies. J Appl Ecol 2018. [DOI: 10.1111/1365-2664.13140] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Joy Coppes
- Wildlife Ecology; Forest Research Institute of Baden-Wuerttemberg FVA; Freiburg Germany
| | - Jim-Lino Kämmerle
- Wildlife Ecology; Forest Research Institute of Baden-Wuerttemberg FVA; Freiburg Germany
- Wildlife Ecology and Wildlife Management; University of Freiburg; Freiburg Germany
| | - Mirjam Willert
- Wildlife Ecology; Forest Research Institute of Baden-Wuerttemberg FVA; Freiburg Germany
| | - Annette Kohnen
- Wildlife Ecology; Forest Research Institute of Baden-Wuerttemberg FVA; Freiburg Germany
| | - Rupert Palme
- Department of Biomedical Sciences; University of Veterinary Medicine; Vienna Austria
| | - Veronika Braunisch
- Wildlife Ecology; Forest Research Institute of Baden-Wuerttemberg FVA; Freiburg Germany
- Conservation Biology; Institute of Ecology and Evolution; University of Bern; Bern Switzerland
| |
Collapse
|
19
|
Pohlin F, Brabender K, Fluch G, Stalder G, Petit T, Walzer C. Seasonal Variations in Heart Rate Variability as an Indicator of Stress in Free-Ranging Pregnant Przewalski's Horses ( E. ferus przewalskii) within the Hortobágy National Park in Hungary. Front Physiol 2017; 8:664. [PMID: 28936179 PMCID: PMC5594093 DOI: 10.3389/fphys.2017.00664] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2017] [Accepted: 08/22/2017] [Indexed: 11/30/2022] Open
Abstract
Background: Ecosystems with seasonal fluctuations in climate and food availability present physiological challenges to resident mammals and may cause “stress.” The two predominant physiological responses to stressors are (1) the activation of the hypothalamic-pituitary-adrenal axis and (2) the modulation of the autonomic nervous system. To date, the primary indicator for “stress” in wildlife- and zoo animal research are glucocorticoid levels. By measuring the autonomic regulation of cardiac activity, particularly the vagal tone, heart rate variability (HRV) is presently emerging as a suitable indicator of “stress” in farm- and domestic animal research. Objective: The aim of this study was to use HRV, a novel method in wildlife research, to assess seasonal patterns of “stress” in a group of free-ranging Przewalski's horses (Equus ferus przewalskii). Methods: Six pregnant Przewalski's horses from one harem within the Hortobágy National Park in Hungary were subjected to the study. We used a dedicated telemetry system consisting of a subcutaneously implanted transmitter and a receiver and storage unit in a collar to record HRV, heart rate (HR), subcutaneous body temperature, and activity throughout a one-year study period—climate data was also collected. We defined “stress” as a decrease in parasympathetic nervous system tone and calculated RMSSD (root mean square of successive differences) as a measure of HRV. Linear mixed effects models with random intercept per individual were used for statistical analysis. Results: HRV and HR varied considerably throughout the year. Similar to temperate ruminants and hibernating mammals, Przewalski's horses experienced lower HR and HRV during winter, when resources are limited indicating decreased metabolic rates coupled with “stress.” In spring, we observed a drop of HRV along with a peak in HR indicating an increase of allostatic load that is most likely associated with increased energy demands during pregnancy and/or seasonal routines such as the adjustment of the gastrointestinal system to better quality diet. Conclusion: Measuring telemetric HRV is a proven method to study undisturbed reactions of wild animals to their changing environment over the long term. Przewalski's horses experience a loss of complexity in cardiovascular dynamics over the winter and particularly during spring, indicating seasonal “stress.”
Collapse
Affiliation(s)
- Friederike Pohlin
- Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine ViennaVienna, Austria
| | | | - Gerhard Fluch
- Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine ViennaVienna, Austria
| | - Gabrielle Stalder
- Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine ViennaVienna, Austria
| | | | - Chris Walzer
- Department of Integrative Biology and Evolution, Research Institute of Wildlife Ecology, University of Veterinary Medicine ViennaVienna, Austria.,Wildlife Conservation SocietyBronx, NY, United States
| |
Collapse
|
20
|
Rehnus M, Palme R. How genetic data improve the interpretation of results of faecal glucocorticoid metabolite measurements in a free-living population. PLoS One 2017; 12:e0183718. [PMID: 28832649 PMCID: PMC5568376 DOI: 10.1371/journal.pone.0183718] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2017] [Accepted: 08/09/2017] [Indexed: 11/18/2022] Open
Abstract
Measurement of glucocorticoid metabolites (GCM) in faeces has become a widely used and effective tool for evaluating the amount of stress experienced by animals. However, the potential sampling bias resulting from an oversampling of individuals when collecting “anonymous” (unknown sex or individual) faeces has rarely been investigated. We used non-invasive genetic sampling (NIGS) to investigate potential interpretation errors of GCM measurements in a free-living population of mountain hares during the mating and post-reproductive periods. Genetic data improved the interpretation of results of faecal GCM measurements. In general GCM concentrations were influenced by season. However, genetic information revealed that it was sex-dependent. Within the mating period, females had higher GCM levels than males, but individual differences were more expressed in males. In the post-reproductive period, GCM concentrations were neither influenced by sex nor individual. We also identified potential pitfalls in the interpretation of anonymous faecal samples by individual differences in GCM concentrations and resampling rates. Our study showed that sex- and individual-dependent GCM levels led to a misinterpretation of GCM values when collecting “anonymous” faeces. To accurately evaluate the amount of stress experienced by free-living animals using faecal GCM measurements, we recommend documenting individuals and their sex of the sampled population. In stress-sensitive and elusive species, such documentation can be achieved by using NIGS and for diurnal animals with sexual and individual variation in appearance or marked individuals, it can be provided by a detailed field protocol.
Collapse
Affiliation(s)
- Maik Rehnus
- Swiss Federal Research Institute for Forest, Snow and Landscape Research WSL, Zürcherstrasse 111, Birmensdorf, Switzerland.,WILDTIER SCHWEIZ, Winterthurerstrasse 92, Zurich, Switzerland
| | - Rupert Palme
- Department of Biomedical Sciences, University of Veterinary Medicine, Veterinärplatz 1, Vienna, Austria
| |
Collapse
|
21
|
Ben Slimen H, Schaschl H, Knauer F, Suchentrunk F. Selection on the mitochondrial ATP synthase 6 and the NADH dehydrogenase 2 genes in hares (Lepus capensis L., 1758) from a steep ecological gradient in North Africa. BMC Evol Biol 2017; 17:46. [PMID: 28173765 PMCID: PMC5297179 DOI: 10.1186/s12862-017-0896-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2016] [Accepted: 01/26/2017] [Indexed: 11/30/2022] Open
Abstract
Background Recent studies of selection on mitochondrial (mt) OXPHOS genes suggest adaptation due mainly to environmental variation. In this context, Tunisian hares that display several external phenotypes with phylogenetically rather homogenous gene pool and shallow population structure provide a good precondition to detect positive selection on mt genes related to environmental/climatic variation, specifically ambient temperature and precipitation. Results We used codon-based methods along with population genetic data to test for positive selection on ATPase synthase 6 (ATP6) and NADH dehydrogenase 2 (ND2) of cape hares (Lepus capensis) collected along a steep ecological gradient in Tunisia. We found significantly higher differentiation at the ATP6 locus across Tunisia, with sub-humid Mediterranean, semi-arid, and arid Sahara climate than for fourteen unlinked supposedly neutrally evolving nuclear microsatellites and mt control region sequences. This suggested positive selection on ATP6 sequences, which was confirmed by several codon-based tests for one sequence site that together with a second site translated into four different amino acids. Positive selection on ND2 sequences was also confirmed by several codon-based tests. The corresponding frequencies of the two most prevalent variants at each locus varied significantly across climate regions, and our logistic general linear models of occurrence of those proteins indicated significant effects of mean annual temperature for ATP6 and mean minimum temperature of the coldest month of the year for ND2, independent of geographical location, annual precipitation, and the respective co-occurring protein at the second locus. Moreover, presence of the ancestral ATP6 protein, as inferred from phylogenetic networks, was positively affected by the simultaneous presence of the derived ND2 protein and vice versa, independent of temperature, precipitation, or geographic location. Finally, we obtained a significant coevolution signal for the ancestral ATP6 and derived ND2 sequences and vice versa. Conclusions positive selection was strongly suggested by the population genetic approach and the codon-based tests in both mtDNA genes. Moreover, the two most prevalent proteins at the ATP6 locus were distributed at significantly varying frequencies across the study area with a significant effect of mean annual temperature on the occurrence of the ATP6 proteins independent of geographical coordinates and the co-occuring ND2 protein variant. For ND2, occurrence of the two most frequent protein variants was significantly influenced by the mean minimum temperature of the coldest month, independent of the co-occurring ATP6 protein variant and geographical coordinates. This strongly suggests direct involvement of ambient temperature in the adaptation of the studied mtOXPHOS genes. Electronic supplementary material The online version of this article (doi:10.1186/s12862-017-0896-0) contains supplementary material, which is available to authorized users.
Collapse
Affiliation(s)
- Hichem Ben Slimen
- UR Génomique des Insectes Ravageurs des Cultures d'Intérêt Agronomique (GIRC), Université de Tunis El-Manar, 2092, El Manar, Tunisia. .,Institut Supérieur de Biotechnologie de Béja, Beja, 9000, Tunisia.
| | - Helmut Schaschl
- Department of Anthropology, University of Vienna, Althanstrasse 14, 1090, Vienna, Austria
| | - Felix Knauer
- Research Institute of Wildlife Ecology, University of Veterinary Medicine Vienna, Savoyenstrasse 1, 1160, Vienna, Austria
| | - Franz Suchentrunk
- Research Institute of Wildlife Ecology, University of Veterinary Medicine Vienna, Savoyenstrasse 1, 1160, Vienna, Austria
| |
Collapse
|