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Benson JF, Dougherty KD, Beier P, Boyce WM, Cristescu B, Gammons DJ, Garcelon DK, Higley JM, Martins QE, Nisi AC, Riley SPD, Sikich JA, Stephenson TR, Vickers TW, Wengert GM, Wilmers CC, Wittmer HU, Dellinger JA. The ecology of human-caused mortality for a protected large carnivore. Proc Natl Acad Sci U S A 2023; 120:e2220030120. [PMID: 36940341 PMCID: PMC10068828 DOI: 10.1073/pnas.2220030120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Accepted: 02/15/2023] [Indexed: 03/22/2023] Open
Abstract
Mitigating human-caused mortality for large carnivores is a pressing global challenge for wildlife conservation. However, mortality is almost exclusively studied at local (within-population) scales creating a mismatch between our understanding of risk and the spatial extent most relevant to conservation and management of wide-ranging species. Here, we quantified mortality for 590 radio-collared mountain lions statewide across their distribution in California to identify drivers of human-caused mortality and investigate whether human-caused mortality is additive or compensatory. Human-caused mortality, primarily from conflict management and vehicles, exceeded natural mortality despite mountain lions being protected from hunting. Our data indicate that human-caused mortality is additive to natural mortality as population-level survival decreased as a function of increasing human-caused mortality and natural mortality did not decrease with increased human-caused mortality. Mortality risk increased for mountain lions closer to rural development and decreased in areas with higher proportions of citizens voting to support environmental initiatives. Thus, the presence of human infrastructure and variation in the mindset of humans sharing landscapes with mountain lions appear to be primary drivers of risk. We show that human-caused mortality can reduce population-level survival of large carnivores across large spatial scales, even when they are protected from hunting.
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Affiliation(s)
- John F. Benson
- School of Natural Resources, University of Nebraska-Lincoln, Lincoln, NE68583
| | - Kyle D. Dougherty
- School of Natural Resources, University of Nebraska-Lincoln, Lincoln, NE68583
| | - Paul Beier
- Center for Large Landscape Conservation, Bozeman, MT59715
| | - Walter M. Boyce
- Karen C. Drayer Wildlife Health Center, School of Veterinary Medicine, University of California, Davis, CA95616
| | - Bogdan Cristescu
- Environmental Studies Department, University of California, Santa Cruz, CA95064
| | | | | | | | | | - Anna C. Nisi
- Environmental Studies Department, University of California, Santa Cruz, CA95064
| | - Seth P. D. Riley
- National Park Service, Santa Monica Mountains National Recreation Area, Thousand Oaks, CA91360
| | - Jeff A. Sikich
- National Park Service, Santa Monica Mountains National Recreation Area, Thousand Oaks, CA91360
| | | | - T. Winston Vickers
- Karen C. Drayer Wildlife Health Center, School of Veterinary Medicine, University of California, Davis, CA95616
| | | | | | - Heiko U. Wittmer
- School of Biological Sciences, Victoria University of Wellington, Wellington6140, New Zealand
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Abstract
AbstractKill rates and functional responses are fundamental to the study of predator ecology and the understanding of predatory-prey dynamics. As the most widely distributed apex predator in the western hemisphere, pumas (Puma concolor) have been well studied, yet a synthesis of their kill rates is currently lacking. We reviewed the literature and compiled data on sex- and age-specific kill rate estimates of pumas on ungulates, and conducted analyses aimed at understanding ecological factors explaining the observed spatial variation. Kill rate studies on pumas, while numerous, were primarily conducted in Temperate Conifer Forests (< 10% of puma range), revealing a dearth of knowledge across much of their range, especially from tropical and subtropical habitats. Across studies, kill rates in ungulates/week were highest for adult females with kitten(s) (1.24 ± 0.41 ungulates/week) but did not vary significantly between adult males (0.84 ± 0.18) and solitary adult females (0.99 ± 0.26). Kill rates in kg/day differed only marginally among reproductive classes. Kill rates of adult pumas increased with ungulate density, particularly for males. Ungulate species richness had a weak negative association with adult male kill rates. Neither scavenger richness, puma density, the proportion of non-ungulate prey in the diet, nor regional human population density had a significant effect on ungulate kill rates, but additional studies and standardization would provide further insights. Our results had a strong temperate-ecosystem bias highlighting the need for further research across the diverse biomes pumas occupy to fully interpret kill rates for the species. Data from more populations would also allow for multivariate analyses providing deeper inference into the ecological and behavioural factors driving kill rates and functional responses of pumas, and apex predators in general.
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Gustafson KD, Gagne RB, Buchalski MR, Vickers TW, Riley SP, Sikich JA, Rudd JL, Dellinger JA, LaCava ME, Ernest HB. Multi‐population puma connectivity could restore genomic diversity to at‐risk coastal populations in California. Evol Appl 2021; 15:286-299. [PMID: 35233248 PMCID: PMC8867711 DOI: 10.1111/eva.13341] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 12/25/2021] [Indexed: 12/01/2022] Open
Abstract
Urbanization is decreasing wildlife habitat and connectivity worldwide, including for apex predators, such as the puma (Puma concolor). Puma populations along California's central and southern coastal habitats have experienced rapid fragmentation from development, leading to calls for demographic and genetic management. To address urgent conservation genomic concerns, we used double‐digest restriction‐site associated DNA (ddRAD) sequencing to analyze 16,285 genome‐wide single‐nucleotide polymorphisms (SNPs) from 401 pumas sampled broadly across the state. Our analyses indicated support for 4–10 geographically nested, broad‐ to fine‐scale genetic clusters. At the broadest scale, the four genetic clusters had high genetic diversity and exhibited low linkage disequilibrium, indicating that pumas have retained genomic diversity statewide. However, multiple lines of evidence indicated substructure, including 10 finer‐scale genetic clusters, some of which exhibited fixed alleles and linkage disequilibrium. Fragmented populations along the Southern Coast and Central Coast had particularly low genetic diversity and strong linkage disequilibrium, indicating genetic drift and close inbreeding. Our results demonstrate that genetically at risk populations are typically nested within a broader‐scale group of interconnected populations that collectively retain high genetic diversity and heterogenous fixations. Thus, extant variation at the broader scale has potential to restore diversity to local populations if management actions can enhance vital gene flow and recombine locally sequestered genetic diversity. These state‐ and genome‐wide results are critically important for science‐based conservation and management practices. Our nested population genomic analysis highlights the information that can be gained from population genomic studies aiming to provide guidance for the conservation of fragmented populations.
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Affiliation(s)
- Kyle D. Gustafson
- Arkansas State University Department of Biological Sciences Jonesboro 72401
| | - Roderick B. Gagne
- University of Pennsylvania School of Veterinary Medicine Department of Pathobiology Kennett Square Wildlife Futures Program PA USA
| | | | - T. Winston Vickers
- University of California ‐ Davis School of Veterinary Medicine Karen C. Drayer Wildlife Health Center Davis 95616
| | - Seth P.D. Riley
- National Park Service Santa Monica Mountains National Recreation Area 401 W. Hillcrest Dr Thousand Oaks 91360
| | - Jeff A. Sikich
- National Park Service Santa Monica Mountains National Recreation Area 401 W. Hillcrest Dr Thousand Oaks 91360
| | - Jaime L. Rudd
- California Department of Fish and Wildlife Rancho Cordova 95670
| | | | - Melanie E.F. LaCava
- Wildlife Genomics and Disease Ecology Laboratory Department of Veterinary Sciences University of Wyoming Laramie 82071
| | - Holly B. Ernest
- Wildlife Genomics and Disease Ecology Laboratory Department of Veterinary Sciences University of Wyoming Laramie 82071
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Dellinger JA, Shores CR, Craig AD, Kachel SM, Heithaus MR, Ripple WJ, Wirsing AJ. Predators reduce niche overlap between sympatric prey. OIKOS 2021. [DOI: 10.1111/oik.08628] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Justin A. Dellinger
- School of Environmental and Forest Sciences, Univ. of Washington Seattle WA USA
- Wildlife Investigations Lab, California Dept of Fish and Wildlife Rancho Cordova CA USA
| | - Carolyn R. Shores
- School of Environmental and Forest Sciences, Univ. of Washington Seattle WA USA
- British Columbia Fish and Wildlife, Ministry of Forests, Lands, Natural Resource Operations and Rural Development Williams Lake BC Canada
| | - Apryle D. Craig
- School of Environmental and Forest Sciences, Univ. of Washington Seattle WA USA
| | - Shannon M. Kachel
- School of Environmental and Forest Sciences, Univ. of Washington Seattle WA USA
- Panthera New York NY USA
| | - Michael R. Heithaus
- Dept of Biological Sciences, Florida International Univ. North Miami FL USA
- Institute of Environment, Florida International Univ. FL USA
| | - William J. Ripple
- Global Trophic Cascades Program, Dept of Forest Ecosystems and Society, Oregon State Univ. Corvallis OR USA
| | - Aaron J. Wirsing
- School of Environmental and Forest Sciences, Univ. of Washington Seattle WA USA
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Dellinger JA, Gustafson KD, Gammons DJ, Ernest HB, Torres SG. Minimum habitat thresholds required for conserving mountain lion genetic diversity. Ecol Evol 2020; 10:10687-10696. [PMID: 33072289 PMCID: PMC7548186 DOI: 10.1002/ece3.6723] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Revised: 07/31/2020] [Accepted: 08/05/2020] [Indexed: 11/24/2022] Open
Abstract
Jointly considering the ecology (e.g., habitat use) and genetics (e.g., population genetic structure and diversity) of a species can increase understanding of current conservation status and inform future management practices. Previous analyses indicate that mountain lion (Puma concolor) populations in California are genetically structured and exhibit extreme variation in population genetic diversity. Although human development may have fragmented gene flow, we hypothesized the quantity and quality of remaining habitat available would affect the genetic viability of each population. Our results indicate that area of suitable habitat, determined via a resource selection function derived using 843,500 location fixes from 263 radio‐collared mountain lions, is strongly and positively associated with population genetic diversity and viability metrics, particularly with effective population size. Our results suggested that contiguous habitat of ≥10,000 km2 may be sufficient to alleviate the negative effects of genetic drift and inbreeding, allowing mountain lion populations to maintain suitable effective population sizes. Areas occupied by five of the nine geographic–genetic mountain lion populations in California fell below this habitat threshold, and two (Santa Monica Area and Santa Ana) of those five populations lack connectivity to nearby populations. Enhancing ecological conditions by protection of greater areas of suitable habitat and facilitating positive evolutionary processes by increasing connectivity (e.g., road‐crossing structures) might promote persistence of small or isolated populations. The conservation status of suitable habitat also appeared to influence genetic diversity of populations. Thus, our results demonstrate that both the area and status (i.e., protected or unprotected) of suitable habitat influence the genetic viability of mountain lion populations.
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Affiliation(s)
| | - Kyle D Gustafson
- Department of Biological Sciences Arkansas State University Jonesboro Arkansas USA.,Wildlife Genomics and Disease Ecology Laboratory University of Wyoming Laramie Wyoming USA
| | - Daniel J Gammons
- California Department of Fish and Wildlife Sacramento California USA
| | - Holly B Ernest
- Wildlife Genomics and Disease Ecology Laboratory University of Wyoming Laramie Wyoming USA
| | - Steven G Torres
- California Department of Fish and Wildlife Sacramento California USA
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Dellinger JA, Cristescu B, Ewanyk J, Gammons DJ, Garcelon D, Johnston P, Martins Q, Thompson C, Vickers TW, Wilmers CC, Wittmer HU, Torres SG. Using Mountain Lion Habitat Selection in Management. J Wildl Manage 2019. [DOI: 10.1002/jwmg.21798] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Affiliation(s)
- Justin A. Dellinger
- California Department of Fish and Wildlife 1701 Nimbus Rd., Suite D Rancho Cordova CA 95670 USA
| | - Bogdan Cristescu
- Center for Integrated Spatial Research, Environmental Studies Department University of California 1156 High St. Santa Cruz CA 95064 USA
| | - Jonathan Ewanyk
- Institute for Wildlife Studies PO Box 1104 Arcata CA 95518 USA
| | - Daniel J. Gammons
- California Department of Fish and Wildlife 787 N Main St., Suite 220 Bishop CA 93514 USA
| | - David Garcelon
- Institute for Wildlife Studies PO Box 1104 Arcata CA 95518 USA
| | | | | | - Craig Thompson
- United States Forest Service, Northern Region 26 Fort Missoula Rd. Missoula MT 59804 USA
| | - T. Winston Vickers
- Wildlife Health Center University of California 1089 Veterinary Medicine Dr. Davis CA 95616 USA
| | - Christopher C. Wilmers
- Center for Integrated Spatial Research, Environmental Studies Department University of California 1156 High St. Santa Cruz CA 95064 USA
| | - Heiko U. Wittmer
- School of Biological Sciences Victoria University of Wellington PO Box 600 Wellington 6140 NZ
| | - Steven G. Torres
- California Department of Fish and Wildlife 1701 Nimbus Rd., Suite D Rancho Cordova CA 95670 USA
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Affiliation(s)
- Justin A. Dellinger
- Wildlife Investigations Laboratory, California Department of Fish and Wildlife, 1701 Nimbus Road, Rancho Cordova, CA 95670 (JAD, SGT)
| | - Neal W. Darby
- Mojave National Preserve, 2701 Barstow Road, Barstow, CA 92311 (NWD)
| | - Steven G. Torres
- Wildlife Investigations Laboratory, California Department of Fish and Wildlife, 1701 Nimbus Road, Rancho Cordova, CA 95670 (JAD, SGT)
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Shores CR, Dellinger JA, Newkirk ES, Kachel SM, Wirsing AJ. Mesopredators change temporal activity in response to a recolonizing apex predator. Behav Ecol 2019. [DOI: 10.1093/beheco/arz080] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Abstract
Apex predators can influence ecosystems through density and behaviorally mediated effects on herbivores and mesopredators. In many parts of the world, apex predators live in, or are returning to, landscapes that have been modified by people; so, it is important to understand their ecological role in anthropogenic landscapes. We used motion-activated game cameras to compare the activity patterns of humans and 2 mesopredators, coyotes (Canis latrans) and bobcats (Lynx rufus), in areas with and without an apex predator, the gray wolf (Canis lupus), in a multiuse landscape of the northwestern United States. In areas with wolves, there was a significant increase in temporal niche overlap between the mesopredators owing to higher levels of coyote activity at all time periods of the day. Temporal overlap between mesopredators and humans also increased significantly in the presence of wolves. Coyotes exposed to wolves increased their activity during dawn, day, and dusk hours. The increase in coyote activity was greatest during the day, when wolves were least active. The direction of change in bobcat activity in areas with wolves was opposite to coyotes, suggesting a behaviorally mediated cascade between wolves, coyotes, and bobcats, although these findings would need to be confirmed with further research. Our findings suggest that mesopredators in human-dominated systems may perceive humans as less dangerous than apex predators, that humans may be more likely to encounter mesopredators in areas occupied by top predators, and that behaviorally mediated effects of apex predators on mesopredators persist in human-dominated landscapes.
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Affiliation(s)
- Carolyn R Shores
- School of Environmental and Forest Sciences, University of Washington, Anderson Hall, West Stevens Way NE, Seattle, WA, USA
- Ministry of Forests, Lands, Natural Resource Operations and Rural Development, Fish and Wildlife, Borland St, Williams Lake, BC, Canada
| | - Justin A Dellinger
- California Department of Fish and Wildlife, Nimbus Rd., Suite D, Rancho Cordova, CA, USA
| | | | - Shannon M Kachel
- School of Environmental and Forest Sciences, University of Washington, Anderson Hall, West Stevens Way NE, Seattle, WA, USA
| | - Aaron J Wirsing
- School of Environmental and Forest Sciences, University of Washington, Anderson Hall, West Stevens Way NE, Seattle, WA, USA
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Dellinger JA, Shores CR, Craig A, Heithaus MR, Ripple WJ, Wirsing AJ. Habitat use of sympatric prey suggests divergent anti-predator responses to recolonizing gray wolves. Oecologia 2018; 189:487-500. [DOI: 10.1007/s00442-018-4323-z] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Accepted: 12/08/2018] [Indexed: 11/29/2022]
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Dellinger JA, Loft ER, Bertram RC, Neal DL, Kenyon MW, Torres SG. Seasonal Spatial Ecology of Mountain Lions (Puma concolor) in the Central Sierra Nevada. WEST N AM NATURALIST 2018. [DOI: 10.3398/064.078.0205] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Affiliation(s)
- Justin A. Dellinger
- Wildlife Investigations Lab, California Department of Fish and Wildlife, 1701 Nimbus Rd., Rancho Cordova, CA 95670
| | - Eric R. Loft
- Wildlife Branch, California Department of Fish and Wildlife, 1416 Ninth St., Sacramento, CA 95814
| | - Ronald C. Bertram
- Wildlife Branch, California Department of Fish and Wildlife, 1416 Ninth St., Sacramento, CA 95814
| | - Donald L. Neal
- United States Forest Service, Pacific Southwest Research Station, 2081 E. Sierra Ave., Fresno, CA 93710
| | - Marc W. Kenyon
- Wildlife Investigations Lab, California Department of Fish and Wildlife, 1701 Nimbus Rd., Rancho Cordova, CA 95670
| | - Steven G. Torres
- Wildlife Investigations Lab, California Department of Fish and Wildlife, 1701 Nimbus Rd., Rancho Cordova, CA 95670
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Hinton JW, Ashley AK, Dellinger JA, Gittleman JL, van Manen FT, Chamberlain MJ. Using diets of Canis breeding pairs to assess resource partitioning between sympatric red wolves and coyotes. J Mammal 2017. [DOI: 10.1093/jmammal/gyw233] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022] Open
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Newsome TM, Boitani L, Chapron G, Ciucci P, Dickman CR, Dellinger JA, López‐Bao JV, Peterson RO, Shores CR, Wirsing AJ, Ripple WJ. Food habits of the world's grey wolves. Mamm Rev 2016. [DOI: 10.1111/mam.12067] [Citation(s) in RCA: 117] [Impact Index Per Article: 14.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- Thomas M. Newsome
- Desert Ecology Research Group School of Biological Sciences University of Sydney New South Wales 2006 Australia
- Global Trophic Cascades Program Department of Forest Ecosystems and Society Oregon State University Corvallis Oregon 97331 USA
- Centre for Integrative Ecology School of Life and Environmental Sciences Deakin University Burwood Victoria 3125 Australia
| | - Luigi Boitani
- Department of Biology and Biotechnologies “Charles Darwin” Sapienza University of Rome Rome 00185 Italy
| | - Guillaume Chapron
- Grimsö Wildlife Research Station Swedish University of Agricultural Sciences SE ‐ 73091 Riddarhyttan Sweden
| | - Paolo Ciucci
- Department of Biology and Biotechnologies “Charles Darwin” Sapienza University of Rome Rome 00185 Italy
| | - Christopher R. Dickman
- Desert Ecology Research Group School of Biological Sciences University of Sydney New South Wales 2006 Australia
| | - Justin A. Dellinger
- School of Environmental and Forest Sciences University of Washington Seattle Washington 98195 USA
| | - José V. López‐Bao
- Grimsö Wildlife Research Station Swedish University of Agricultural Sciences SE ‐ 73091 Riddarhyttan Sweden
- Grimsö Wildlife Research Station Research Unit of Biodiversity Oviedo University 33600 Mieres Spain
| | - Rolf O. Peterson
- School of Forest Resources and Environmental Science Michigan Technological University Houghton Michigan 49931 USA
| | - Carolyn R. Shores
- School of Environmental and Forest Sciences University of Washington Seattle Washington 98195 USA
| | - Aaron J. Wirsing
- School of Environmental and Forest Sciences University of Washington Seattle Washington 98195 USA
| | - William J. Ripple
- Global Trophic Cascades Program Department of Forest Ecosystems and Society Oregon State University Corvallis Oregon 97331 USA
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Newsome TM, Ballard GA, Crowther MS, Dellinger JA, Fleming PJS, Glen AS, Greenville AC, Johnson CN, Letnic M, Moseby KE, Nimmo DG, Nelson MP, Read JL, Ripple WJ, Ritchie EG, Shores CR, Wallach AD, Wirsing AJ, Dickman CR. Resolving the value of the dingo in ecological restoration. Restor Ecol 2015. [DOI: 10.1111/rec.12186] [Citation(s) in RCA: 56] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Thomas M. Newsome
- Desert Ecology Research Group, School of Biological Sciences; The University of Sydney; New South Wales 2006 Australia
- Department of Forest Ecosystems and Society; Oregon State University; Corvallis OR 97331 U.S.A
| | - Guy-Anthony Ballard
- School of Environmental and Rural Sciences; University of New England; Armidale New South Wales 2351 Australia
- Vertebrate Pest Research Unit, Biosecurity NSW, NSW Department of Primary Industries; University of New England; PO Box U86 Armidale New South Wales 2351 Australia
| | - Mathew S. Crowther
- Desert Ecology Research Group, School of Biological Sciences; The University of Sydney; New South Wales 2006 Australia
| | - Justin A. Dellinger
- School of Environmental and Forest Sciences; University of Washington; Seattle WA 98195 U.S.A
| | - Peter J. S. Fleming
- School of Environmental and Rural Sciences; University of New England; Armidale New South Wales 2351 Australia
- Vertebrate Pest Research Unit, Biosecurity NSW; NSW Department of Primary Industries; Locked Bag 6006 Orange New South Wales 2800 Australia
| | | | - Aaron C. Greenville
- Desert Ecology Research Group, School of Biological Sciences; The University of Sydney; New South Wales 2006 Australia
| | - Chris N. Johnson
- School of Biological Sciences; University of Tasmania; Private Bag 55 Hobart Tasmania 7001 Australia
| | - Mike Letnic
- Centre for Ecosystem Science, and School of Biological, Earth and Environmental Sciences; University of New South Wales; Sydney New South Wales 2052 Australia
| | - Katherine E. Moseby
- School of Earth and Environmental Sciences; The University of Adelaide; South Australia 5005 Australia
- Arid Recovery; PO Box 147 Roxby Downs South Australia 5725 Australia
| | - Dale G. Nimmo
- Centre for Integrative Ecology, School of Life and Environmental Sciences; Deakin University; Melbourne Burwood Campus, 221 Burwood Highway Burwood Victoria 3125 Australia
| | - Michael Paul Nelson
- Department of Forest Ecosystems and Society; Oregon State University; Corvallis OR 97331 U.S.A
| | - John L. Read
- School of Earth and Environmental Sciences; The University of Adelaide; South Australia 5005 Australia
- Arid Recovery; PO Box 147 Roxby Downs South Australia 5725 Australia
| | - William J. Ripple
- Department of Forest Ecosystems and Society; Oregon State University; Corvallis OR 97331 U.S.A
| | - Euan G. Ritchie
- Centre for Integrative Ecology, School of Life and Environmental Sciences; Deakin University; Melbourne Burwood Campus, 221 Burwood Highway Burwood Victoria 3125 Australia
| | - Carolyn R. Shores
- School of Environmental and Forest Sciences; University of Washington; Seattle WA 98195 U.S.A
| | - Arian D. Wallach
- Charles Darwin University; Research Institute for the Environment and Livelihoods; Darwin Northern Territory 0909 Australia
| | - Aaron J. Wirsing
- School of Environmental and Forest Sciences; University of Washington; Seattle WA 98195 U.S.A
| | - Christopher R. Dickman
- Desert Ecology Research Group, School of Biological Sciences; The University of Sydney; New South Wales 2006 Australia
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Dellinger JA, Mcvey JM, Cobb DT, Moorman CE. Diameter thresholds for distinguishing between red wolf and other canid scat. WILDLIFE SOC B 2011. [DOI: 10.1002/wsb.60] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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Gerstenberger SL, Dellinger JA, Hansen LG. Concentrations and frequencies of polychlorinated biphenyl congeners in a Native American population that consumes Great Lakes fish. J Toxicol Clin Toxicol 2001; 38:729-46. [PMID: 11192460 DOI: 10.1081/clt-100102386] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
Abstract
OBJECTIVE Polychlorinated biphenyl congener profiles were examined in serum samples from 61 Native American (Ojibwa) volunteers who regularly consumed fish harvested from the Great Lakes region. A total of 93 peaks are reported which represent 126 individual chlorobiphenyls. RESULTS When ranked by frequency, 13 peaks comprising single or co-eluting chlorobiphenyls occurred in all 61 samples (a frequency of 100%). These included chlorobiphenyls 138 + 158 + 163, 105 + 132 + 153, 180, 118, 196 + 203, 74, 182 + 187, 199, 183, 114 + 134, 195 + 208, 206, and 194. These 13 peaks also occurred at concentrations higher than those of all other measured chlorobiphenyls, except for the addition of the peak containing chlorobiphenyls 170 and 190, which was below detection in 15% of the samples and ranked fifth in average concentration. The highly chlorinated chlorobiphenyls resembled human serum profiles previously reported in the literature. METHODS Individual chlorobiphenyls were identified using a gas chromatograph equipped with a 60-meter DB-5 capillary column and electron capture detection. CONCLUSION When compared to other human residue analyses for fish-eating populations, the Ojibwa samples contained higher proportions of lightly chlorinated and labile chlorobiphenyls such as 8, 16 + 32, 17, 18, 25, 41 + 64 + 71, 33, 52, 110, and 129. These proportions were similar to those found in carp, whitefish, or whitefish livers harvested from the Great Lakes region. These data indicate that regular meals of lower trophic level fish, such as whitefish from the Great Lakes, may distort steady-state human chlorobiphenyl profiles with respect to certain lightly chlorinated or labile chlorobiphenyls.
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Affiliation(s)
- S L Gerstenberger
- Department of Environmental Studies, University of Nevada, Las Vegas 89154-4030, USA.
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Gerstenberger SL, Heimler I, Smies R, Hutz RJ, Dasmahapatra AK, Tripoli V, Dellinger JA. Minimal endocrine alterations in rodents after consumption of lake trout (Salvelinus namaycush). Arch Environ Contam Toxicol 2000; 38:371-376. [PMID: 10667936 DOI: 10.1007/s002449910049] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
Polychlorinated biphenyls (PCBs) and dioxins are known to cause disruptions in circulating hormone concentrations, which may influence fertility and normal fetal development. Structure activity relationships have been determined for individual congeners, but it is unclear what impacts occur due to exposure to complex mixtures of chemicals found in the environment. Most laboratory studies of PCB exposure have used commercial mixtures in high doses, which may not be representative of environmental concentrations of individual congeners, nor accurately represent complex interactions of multiple contaminants. The present study investigated endocrine alterations in rats associated with the consumption of lake trout collected from three specific locations in the Great Lakes. Composite fish samples were analyzed for PCBs, organochlorines, and mercury and ranged from 415 ppb to 1,275 ppb for individual contaminants. Fillet composites were fed to timed-pregnant Long-Evans rats as 30% of their diet. Concentrations of total thyroxine and estrogen were not significantly different in offspring of dosed dams from that of controls. However, aromatase activity was lowered in all dosed groups as compared with controls. This may represent a lowered expression of the CYP 19 gene in exposed rats or may be due to the presence of one or more substances in the contaminants that are capable of altering the affinity of the aromatase enzyme for its normal endogenous substrate. It is also possible that the number of maturing follicles in the lake trout-fed rats may be fewer than controls, which would result in an overall reduction in the enzyme activity. Data regarding the endocrine effects of environmental contaminant mixtures found in fish from the Great Lakes Basin are still controversial. Additionally, information is scarce with respect to the F1 generation of laboratory animals following environmental maternal exposures, therefore, we investigated the reproductive-endocrine alterations in rat offspring associated with the consumption of lake trout (Salvelinus namaycush) collected from three areas in the Great Lakes.
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Affiliation(s)
- S L Gerstenberger
- University of Nevada, Las Vegas, Department of Environmental Studies, 4505 Maryland Parkway, Las Vegas, Nevada 89154-4030, USA
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Tavris DR, Malek LL, Dellinger JA. Age- and gender-adjusted comparison of Wisconsin native mortality with general Wisconsin population, for diabetes and diabetes-related causes of death--1986-1995. WMJ 1998; 97:58-61. [PMID: 9540452] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
UNLABELLED To compare mortality for diabetes and diabetes-related causes in Native American (NA) with total mortality for Wisconsin population by age, and gender. METHODS Adjusting for age and sex, standardized mortality ratios (SMRs) were calculated for Wisconsin Native Americans for 1986-1995, using the 1990 total Wisconsin population as a reference and death certificate data to count and categorize deaths. RESULTS Statistically significant high NA SMRs were found for total deaths (SMR = 1.28, p < .005), diabetes (SMR = 2.87, p < .005), heart disease (SMR = 1.16, p < .005), and kidney disease (SMR = 2.72, p < .005). There was substantial concordance in SMRs between men and women. NA SMRs were above 1 for all five year age groups below 75. Comparisons are provided with national data. CONCLUSION Mortality due to diabetes mellitus, heart disease and kidney disease are higher among Native Americans in Wisconsin for all age groups below 75 and in both genders.
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Affiliation(s)
- D R Tavris
- Department of Preventive Medicine, Medical College of Wisconsin, Milwaukee 53226, USA
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Gerstenberger SL, Tavris DR, Hansen LK, Pratt-Shelley J, Dellinger JA. Concentrations of blood and hair mercury and serum PCBs in an Ojibwa population that consumes Great Lakes region fish. J Toxicol Clin Toxicol 1997; 35:377-86. [PMID: 9204098 DOI: 10.3109/15563659709043370] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
OBJECTIVE This paper describes an exposure assessment of an American Indian population using blood and hair samples as indicators of mercury and polychlorinated biphenyl exposure from the consumption of fish taken from the Great Lakes region. METHODS Questionnaires regarding fish consumption were completed by 89 Ojibwa tribal members. Mercury concentrations were determined in human hair and blood samples, and polychlorinated biphenyl concentrations were determined in serum. RESULTS Fish were consumed at the highest rates in April, May, June, and July. Lake trout, whitefish, and walleye were the preferred fish consumed by 91.4% of the respondents. Concentrations of blood mercury were all below 55 micrograms/L (ppb), while concentrations of mercury in hair were all less than 3 mg/L (ppm). Hair mercury concentrations were correlated with the previous year's fish consumption (p = .05). Dental amalgams and blood mercury concentrations were also significantly correlated (p < .002). Serum polychlorinated biphenyl concentrations, determined as the sum of 89 congeners, were all below 9.6 ppb total polychlorinated biphenyls. Subject age and total serum polychlorinated biphenyls were correlated (p < .001). CONCLUSIONS The concentrations of mercury and polychlorinated biphenyls in this Ojibwa population were relatively low, but several individuals were identified as having elevated concentrations and additional testing may be warranted. Since the accumulation of contaminants was related to fish consumption and age, a long-term monitoring program that assesses chronic exposure to fish diets would be beneficial.
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Affiliation(s)
- S L Gerstenberger
- Department of Preventive Medicine, Medical College of Wisconsin, Milwaukee 53226, USA.
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Gerstenberger SL, Gilbert JH, Dellinger JA. Environmental contaminants and cholinesterase activity in the brain of fisher (Martes pennanti) harvested in northern Wisconsin. Bull Environ Contam Toxicol 1996; 56:866-872. [PMID: 8661874 DOI: 10.1007/s001289900126] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Affiliation(s)
- S L Gerstenberger
- University of Illinois at Urbana-Champaign, Department of Veterinary Biosciences, 2001 S. Lincoln Avenue, Urbana, Illinois 61801, USA
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21
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Abstract
The Ojibwa Health Study is a descriptive epidemiology study of six Ojibwa reservations in the Upper Great Lakes. Fish consumption habits, contaminant (mercury [Hg], polychlorinated biphenyls [PCBs], and other organochlorines [OCs]) residues in dietary fish and humans, and chronic disease outcomes currently are being documented. Four hundred and fifty questionnaires and approximately 200 biological samples had been collected as of December 1994. Fish collections from reservations included lake trout, walleye, lake whitefish, and lake herring from Lakes Superior (three sites), Michigan, and Huron. Hg and OC residue analyses have been completed for the fish composite samples. A preliminary examination of the data has revealed regional differences in the contaminant burdens of the fish. Lake Michigan and Lake Huron whitefish composite samples had approximately twice the OC concentrations of Lake Superior whitefish samples. In general, the whitefish composite samples were far below the U.S. Food and Drug Administration or any state advisory limits for OC or Hg residues. Lake trout samples contained higher amounts of all residues than did the whitefish samples.
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Affiliation(s)
- J A Dellinger
- Department of Preventive Medicine, Medical College of Wisconsin, Milwaukee 53226, USA
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Harlin KS, Dellinger JA. Retina, brain and blood cholinesterase levels in cats treated with oral dichlorvos. Vet Hum Toxicol 1993; 35:201-3. [PMID: 8351788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Dichlorvos (DDVP) is used as an antihelmetic, principally in dogs, cats, pigs and horses. Retina, whole blood, erythrocyte, plasma and brain cholinesterase (ChE) activities were monitored following DDVP exposure in cats to establish their use as indicators of exposure to a ChE inhibitor. Following DDVP exposure, whole blood ChE activity was 16.8% of preexposure, erythrocyte ChE activity was 33% of preexposure, and plasma ChE was 19% of preexposure values. Brain and retinal ChE activities were reduced to 45% and 43% of control values. Retinal ChE paralleled brain activity.
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Affiliation(s)
- K S Harlin
- Department of Veterinary Biosciences, College of Veterinary Medicine, University of Illinois, Urbana 61801
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Gerstenberger SL, Pratt-Shelley J, Beattie MS, Dellinger JA. Mercury concentrations of walleye (Stizostedion vitreum vitreum) in 34 northern Wisconsin lakes. Bull Environ Contam Toxicol 1993; 50:612-617. [PMID: 8467150 DOI: 10.1007/bf00191254] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
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Abstract
Pharmacologic challenges and dose/response studies are discussed as tools for aiding in the extrapolation of nonhuman animal models to human neurotoxicology. Specific experiments conducted using humans, baboons, rhesus monkeys, and dogs are cited as examples of the use of pharmacologic methods for neurotoxicology applications. Respiratory sinus arrhythmias are quantified following atropine sulfate administration and the resulting vagolytic blockade is used as a pharmacologic challenge technique. Dose/response studies in humans and rhesus monkeys are cited as an example for interspecies comparisons using ED50 calculations for a 30% decrease in the respiratory sinus arrhythmias following atropine. Pharmacologic challenges with drugs of relevant mechanisms of action are useful for demonstrating relative physiologic responses for interspecies extrapolations.
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Affiliation(s)
- J A Dellinger
- Center for Lake Superior Environmental Studies, University of Wisconsin, Superior 54880
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Cook WO, Dellinger JA, Singh SS, Dahlem AM, Carmichael WW, Beasley VR. Regional brain cholinesterase activity in rats injected intraperitoneally with anatoxin-a(s) or paraoxon. Toxicol Lett 1989; 49:29-34. [PMID: 2815113 DOI: 10.1016/0378-4274(89)90097-0] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Adult male Long-Evans rats were injected intraperitoneally with 1.5, 3.0 or 9.0 micrograms/kg of anatoxin-a(s) that had been extracted from laboratory-grown Anabaena flos-aquae NRC-525-17, 800 micrograms/kg of paraoxon, or a control solution. Blood, anterior spinal cord, and brain cerebellar, cortical, medullary, midbrain, hippocampal, hypothalamic, olfactory and striatal cholinesterase activity was determined in rats that died prior to 2 hours or were anesthetized and killed at 2 hours. Unlike paraoxon, anatoxin-a(s) did not cause detectable inhibition of cholinesterase in the central nervous system, but did cause inhibition of cholinesterase in blood, suggesting that anatoxin-a(s) is strictly a peripheral cholinesterase inhibitor.
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Affiliation(s)
- W O Cook
- Department of Veterinary Biosciences, University of Illinois, Urbana 61801
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Abstract
Atropine and methylatropine (190 nmol/kg) were compared in rhesus monkeys (Macaca mulatta) for their ability to produce a cardiac vagal blockade using a noninvasive estimate of respiratory sinus arrhythmia (RSA). Twelve monkeys received both drugs via intravenous (IV) and intramuscular (IM) routes of administration and were monitored for 3 hr after treatment. Both drugs, regardless of the route of administration, reduced RSA amplitude. At this dose, methylatropine was more effective than atropine in its ability to reduce RSA amplitude, heart period (HP; beat-to-beat interval), and overall heart period variability (HPV). Estimated RSA amplitude and HPV returned to basal levels significantly earlier after IM atropine administration than after IV treatment. Methylatropine did not exhibit any route effects. In addition, the mean decrease in RSA amplitude and HPV for the IM route of atropine sulfate was significantly less than that for the IV route. Serum atropine concentrations correlated significantly with all variables after IM treatment but only with RSA and HPV after IV treatment. Methylatropine may therefore be more useful than atropine as a pharmacologic challenge drug for detecting organophosphorus (OP) exposure because of its longer duration of action, lack of route of administration differences, and less likelihood of crossing the blood-brain barrier. Further studies are needed to fully evaluate methylatropine's potential in the challenge method of OP detection.
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Affiliation(s)
- H T Jansen
- Department of Veterinary Biosciences, University of Illinois, Urbana 61801
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Abstract
An estimate of the amplitude of respiratory sinus arrhythmia (V) has been proposed as a noninvasive measure of parasympathetic activity. This experiment monitored V in response to a subclinical dose of pyridostigmine bromide (PYR) and a pharmacological challenge of atropine sulfate (ATR). Twelve male rhesus macaques received 200 micrograms/kg of PYR 30 min prior to an injection of 0, 14, 44, or 140 micrograms/kg ATR. The decrease in V after both the 44 and 140 micrograms/kg ATR doses was similar to the response to ATR alone in a previous experiment. The 14 micrograms/kg dose of ATR did not significantly decrease V in this experiment, which is in contrast with the large decrease of V after ATR alone in a previous experiment. Neither drug affected respiration. The dose of ATR which would be effective in causing a 30% decrease of V in the presence of PYR was estimated to be 18.3 micrograms/kg of ATR. This is twice the dose of ATR calculated to have the same effect without PYR. The attenuated response of V after a pharmacological challenge of ATR may be used to quantify the latent muscarinic effects from exposure to anticholinesterase agents. The attenuated response to ATR may also be useful for evaluating the return of normal cholinergic function after disruption by cholinesterase inhibitors.
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Affiliation(s)
- S G Birnbaum
- Department of Environmental Science, Cook College, Rutgers University, New Brunswick, NJ 08903
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Abstract
A vagal tone monitor (VTM) was used to evaluate cardiac rhythm changes in Rhesus monkeys (Macaca mulatta) after intramuscular (i.m.) administration of an anti-cholinergic (atropine sulfate), two carbamates (pyridostigmine bromide and physostigmine salicylate), and combinations of pyridostigmine and atropine. Twelve monkeys were studied in 4 experiments using Latin Square blind designs. Experiment I tested the VTM responses to atropine sulfate injections of 0, 14, 44 and 140 micrograms/kg. Experiment II tested the responses to 0, 100, 200 and 400 micrograms/kg pyridostigmine injections. Experiment III tested the responses to physostigmine injections of 0, 25, 50 and 100 micrograms/kg. Experiment IV tested the same atropine sulfate treatments as Experiment I 30 min after a pyridostigmine pretreatment of 200 micrograms/kg. The VTM analysis produced an estimate of vagal tone (V) every 30 s, and V was averaged over 15 min. The results indicated that V responded more to physostigmine and atropine than pyridostigmine. There was also an attenuated response to atropine following pyridostigmine pretreatment. The attenuated response had been demonstrated earlier in organophosphate (OP) treated dogs. The results suggest that V may be used as a non-invasive indicator of cholinergic drug effects.
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Affiliation(s)
- J A Dellinger
- Department of Veterinary Biosciences, University of Illinois, Urbana 61801
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Abstract
Twelve juvenile to adult rhesus macaques were administered atropine sulfate (0, 14, 44, and 140 mcg/kg IM). The amplitude of the respiratory sinus arrhythmia (RSA) in the rhesus macaque was estimated using a Vagal Tone Monitor (VTM). The estimate of RSA (termed V; vagal tone) was significantly reduced for nearly 3 hr after all doses of atropine, suggesting possible central nervous system effects. Heart period (R-R interval) was reduced briefly after dosing. Overall heart period variability (HPV) was depressed after all doses of atropine. The amount of atropine required to decrease HPV and V by 30% was similar to that reported for the human. The rhesus monkey was determined to have little resting vagal tone as estimated by V. A large slow wave oscillation contributed to the overall variability in heart period. It is concluded that the rhesus monkey exhibits a similar sensitivity to atropine as did the human and, therefore, provides a useful model for the study of cholinergic drug actions and their effects on RSA.
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Affiliation(s)
- H T Jansen
- Department of Veterinary Biosciences, University of Illinois, Urbana 61801
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Cook WO, Beasley VR, Dahlem AM, Dellinger JA, Harlin KS, Carmichael WW. Comparison of effects of anatoxin-a(s) and paraoxon, physostigmine and pyridostigmine on mouse brain cholinesterase activity. Toxicon 1988; 26:750-3. [PMID: 3188065 DOI: 10.1016/0041-0101(88)90282-6] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Anatoxin-a(s), an alkaloid neurotoxin from the freshwater cyanobacterium, Anabaena flos-aquae NRC-525-17, was compared to paraoxon, physostigmine and pyridostigmine for effects on brain cholinesterase after i.p. injection into Balb/c mice. The duration of clinical signs in mice injected with anatoxin-a(s) persisted longer than in mice given the carbamates and was comparable with that of paraoxon. Anatoxin-a(s) did not inhibit brain cholinesterase activity suggesting that this toxin is unable to cross the blood-brain barrier.
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Affiliation(s)
- W O Cook
- Department of Veterinary Biosciences, College of Veterinary Medicine, University of Illinois, Urbana 61801
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Abstract
Dichlorvos (dimethyl 2,2-dichlorovinyl phosphate) was administered orally to German Shorthair Pointer dogs at approximately 60 mg/kg (twice the usual clinical dose). Plasma and erythrocyte cholinesterase (ChE) was monitored prior to, 90 min, and 180 min post-ingestion. 2-PAM (20 mg/kg IV) and atropine sulfate (0.022 mg/kg IM) were administered 90 min after the dichlorvos to paired treated and control dogs. The telemetered electrocardiographic (ECG) signal was analyzed by a Vagal Tone Monitor (VTM) to yield mean heart period (msec) and an estimate of the amplitude of respiratory sinus arrhythmia (V in natural log values of msec2) for five min intervals. Dichlorvos did not cause cholinomimetic symptoms even though blood cholinesterase was significantly inhibited (plasma -51.3% and erythrocyte -43.7%). The atropine sulfate treatment resulted in the expected vagolytic effects in both the control and the dichlorvos treated dogs, but the atropine effects were attenuated in the latter dogs. Three weeks later, ChE activity was not significantly depressed in the dichlorvos treated dogs, and their V responses to atropine were more similar to the responses in control dogs.
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Abstract
Male Sprague-Dawley rats (three per treatment group) were administered 0, 2, 10, 20, or 40 mg aluminum per kilogram ip per day for 3 days as aluminum chloride in saline. Animals were killed 24 hr later. Aluminum was found to inhibit hepatic drug metabolism in a dose-dependent fashion. The lowest dose (2 mg or 75 mumol/kg) had no effect on the parameters measured, whereas the highest dose (40 mg or 1.5 mmol/kg) caused a 52% decrease in cytochrome P-450, a 71% decrease in p-nitrophenetole O-deethylase activity, and a 77% decrease in ethylmorphine N-demethylase activity. Hepatic glutathione levels were unaffected by aluminum, whereas metallothionein (MT) was induced in both liver and kidney. The distribution of endogenous metals normally associated with MT was altered by aluminum administration. At the highest dose of aluminum (40 mg/kg), zinc levels were increased in liver cytosol (154%), while copper levels were unchanged in liver, but decreased in kidney (70%). Aluminum was present in the liver and kidney. Of the aluminum in the liver, less than 5% was in the cytosol, bound to a MT-like protein. It is concluded that acute ip administration of aluminum adversely effects hepatic drug metabolism and that aluminum induces and binds to MT or a MT-like protein.
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Dellinger JA, Taylor HL, Porges SW. Atropine sulfate effects on aviator performance and on respiratory-heart period interactions. Aviat Space Environ Med 1987; 58:333-8. [PMID: 3579820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
In this study, 20 human volunteers received a placebo and atropine doses of 0.5, 1.0, 2.0, and 4.0 mg X 75 kg-1 in a Latin Square double blind design, and effects were monitored for 3 h postinjection. The 2.0 mg and the 4.0 mg doses resulted in significant flight simulator performance decrements beginning at 1 h postinjection with only minimal recovery by 3 h postinjection. Electrocardiogram data were used to estimate the amplitude of respiratory sinus arrhythmia (RSA) which was more sensitive than mean heart period or mean heart period variance to the effects of atropine. These parasympathetic effects were relatively rapid in onset and peaked within the first 40-min period for the 2.0 and 4.0 mg doses. The onset of performance effects were delayed 1 h 40 min for the 2.0 mg and 1 h 00 min for the 4.0 mg treatment.
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Dellinger JA, Taylor HL, Richardson BC. Comparison of the effects of atropine sulfate and ethanol on performance. Aviat Space Environ Med 1986; 57:1185-8. [PMID: 3800819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
The flight simulator performance decrements resulting from atropine injections were compared to similar decrements resulting from ethanol toxicosis. There were 20 volunteers that received 0.0, 0.5, 1.0, 2.0, and 4.0 X 75 kg-1 of atropine sulfate under double-blind conditions. The performance decrements at each atropine sulfate treatment level for each subject were determined by computing root mean square (RMS) deviations for five flight performance variables. The data set from a previous study concerned with the effects of ethanol on pilot performance was reanalyzed, and the decrements for the five variables at the 0.082% blood alcohol level (BAL) were computed. Probit analysis was used to estimate the effective dose (ED50) at which 50% of the subjects in the atropine sulfate experiment were expected to display decrements in excess of those observed for the 0.082% BAL. The ED50 was 3.12 mg of atropine sulfate.
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Dellinger JA. Monitoring the chronic effects of anticholinesterase pesticides in aerial applicators. Vet Hum Toxicol 1985; 27:427-30. [PMID: 4060562] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
Four pilots were monitored over a six month period for physiological signs of anticholinesterase exposures in this preliminary study. Two pilots were controls and two were aerial applicators whose spraying activities included the application of ethyl parathion on more than 85% of their total acreages. Erythrocytic and plasma cholinesterase assays, plus dark-adapted pupil dilation, and a measure of the amplitude of respiratory sinus arrhythmia (RSA), were measured pre-seasonally and near the end of the spraying season. Comparisons between the controls and the two aerial applicators indicated that one aerial applicator displayed organophosphorus toxicosis symptoms. Dark-adapted pupil dilation and RSA more clearly indicated the chronic exposure than did the blood cholinesterase assays. The alleged exposure was linked by post-study interviews to flight pattern and residue cleaning procedures.
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Dellinger JA, Taylor HL. Measuring the effects of neurotoxicants on flight simulator performance. Aviat Space Environ Med 1985; 56:254-7. [PMID: 3985907] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The Aviation Research Laboratory has developed a methodology for evaluating toxicant effects on pilot performance. Flight data are collected using a digital flight simulator, the ILLIMAC (ILLInois Micro Aviation Computer), during holding patterns and instrument landing system approaches. The flight data are recorded by a separate microcomputer, which also presents the Sternberg memory searching task. A preliminary study examined pilot performance in the simulator and cholinesterase inhibition by insecticides in agricultural pilots. The correlation between the physiological parameters and the pilot performance data was determined. Experiments are planned to determine the effects of a variety of drugs on pilot performance. Neurotoxicants to be studied include ethanol, three antiemetic drugs, and atropine sulfate.
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