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1.
Nature ; 574(7777): 242-245, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31554971

RESUMEN

The Chicxulub bolide impact 66 million years ago drove the near-instantaneous collapse of ocean ecosystems. The devastating loss of diversity at the base of ocean food webs probably triggered cascading extinctions across all trophic levels1-3 and caused severe disruption of the biogeochemical functions of the ocean, and especially disrupted the cycling of carbon between the surface and deep sea4,5. The absence of sufficiently detailed biotic data that span the post-extinction interval has limited our understanding of how ecosystem resilience and biochemical function was restored; estimates6-8 of ecosystem 'recovery' vary from less than 100 years to 10 million years. Here, using a 13-million-year-long nannoplankton time series, we show that post-extinction communities exhibited 1.8 million years of exceptional volatility before a more stable equilibrium-state community emerged that displayed hallmarks of resilience. The transition to this new equilibrium-state community with a broader spectrum of cell sizes coincides with indicators of carbon-cycle restoration and a fully functioning biological pump9. These findings suggest a fundamental link between ecosystem recovery and biogeochemical cycling over timescales that are longer than those suggested by proxies of export production7,8, but far shorter than the return of taxonomic richness6. The fact that species richness remained low as both community stability and biological pump efficiency re-emerged suggests that ecological functions rather than the number of species are more important to community resilience and biochemical functions.


Asunto(s)
Aclimatación , Biodiversidad , Ecosistema , Extinción Biológica , Animales , Isótopos de Carbono/análisis , Cadena Alimentaria , Fósiles , Historia Antigua , Plancton/clasificación , Plancton/aislamiento & purificación
2.
Ecol Appl ; 32(3): e2544, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35080801

RESUMEN

In the United States, the Bald and Golden Eagle Protection Act prohibits take of golden eagles (Aquila chrysaetos) unless authorized by permit, and stipulates that all permitted take must be sustainable. Golden eagles are unintentionally killed in conjunction with many lawful activities (e.g., electrocution on power poles, collision with wind turbines). Managers who issue permits for incidental take of golden eagles must determine allowable take levels and manage permitted take accordingly. To aid managers in making these decisions in the western United States, we used an integrated population model to obtain estimates of golden eagle vital rates and population size, and then used those estimates in a prescribed take level (PTL) model to estimate the allowable take level. Estimated mean annual survival rates for golden eagles ranged from 0.70 (95% credible interval = 0.66-0.74) for first-year birds to 0.90 (0.88-0.91) for adults. Models suggested a high proportion of adult female golden eagles attempted to breed and breeding pairs fledged a mean of 0.53 (0.39-0.72) young annually. Population size in the coterminous western United States has averaged ~31,800 individuals for several decades, with λ = 1.0 (0.96-1.05). The PTL model estimated a median allowable take limit of ~2227 (708-4182) individuals annually given a management objective of maintaining a stable population. We estimate that take averaged 2572 out of 4373 (59%) deaths annually, based on a representative sample of transmitter-tagged golden eagles. For the subset of golden eagles that were recovered and a cause of death determined, anthropogenic mortality accounted for an average of 74% of deaths after their first year; leading forms of take over all age classes were shooting (~670 per year), collisions (~611), electrocutions (~506), and poisoning (~427). Although observed take overlapped the credible interval of our allowable take estimate and the population overall has been stable, our findings indicate that additional take, unless mitigated for, may not be sustainable. Our analysis demonstrates the utility of the joint application of integrated population and prescribed take level models to management of incidental take of a protected species.


Asunto(s)
Águilas , Factores de Edad , Animales , Causas de Muerte , Femenino , Humanos , Propilaminas , Sulfuros , Tasa de Supervivencia , Estados Unidos
3.
Philos Trans A Math Phys Eng Sci ; 376(2130)2018 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-30177560

RESUMEN

Past global warming events such as the Palaeocene-Eocene Thermal Maximum (PETM-56 Ma) are attributed to the release of vast amounts of carbon into the ocean, atmosphere and biosphere with recovery ascribed to a combination of silicate weathering and organic carbon burial. The phytoplanktonic nannoplankton are major contributors of organic and inorganic carbon but their role in this recovery process remains poorly understood and complicated by their contribution to marine calcification. Biocalcification is implicated not only in long-term carbon burial but also both short-term positive and negative climatic feedbacks associated with seawater buffering and responses to ocean acidification. Here, we use exceptional records of preserved fossil coccospheres to reconstruct cell size distribution, biomass production (particulate organic carbon, POC) and (particulate) inorganic carbon (PIC) yields of three contrasting nannoplankton communities (Bass River-outer shelf, Maud Rise-uppermost bathyal, Shatsky Rise-open ocean) through the PETM onset and recovery. Each of the sites shows contrasting community responses across the PETM as a function of their taxic composition and total community biomass. Our results indicate that nannoplankton PIC:POC had no role in short-term climate feedback and, as such, their importance as a source of CO2 to the environment is a red herring. It is nevertheless likely that shifts to greater numbers of smaller cells at the shelf site in particular led to greater carbon transfer efficiency, and that nannoplankton productivity and export across the shelves had a significant modulating effect on carbon sequestration during the PETM recovery.This article is part of a discussion meeting issue 'Hyperthermals: rapid and extreme global warming in our geological past'.


Asunto(s)
Calcificación Fisiológica , Fenómenos Geológicos , Plancton/fisiología , Temperatura , Biomasa , Cambio Climático , Planeta Tierra , Fósiles , Nutrientes/metabolismo , Plancton/metabolismo
4.
Emerg Infect Dis ; 23(12): 1958-1965, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28841405

RESUMEN

Wellfleet Bay virus (WFBV), a novel orthomyxovirus in the genus Quaranjavirus, was first isolated in 2006 from carcasses of common eider (Somateria mollissima) during a mortality event in Wellfleet Bay (Barnstable County, Massachusetts, USA) and has since been repeatedly isolated during recurrent mortality events in this location. Hepatic, pancreatic, splenic, and intestinal necrosis was observed in dead eiders. We inoculated 6-week-old common eider ducklings with WFBV in an attempt to recreate the naturally occurring disease. Approximately 25% of inoculated eiders had onset of clinical disease and required euthanasia; an additional 18.75% were adversely affected based on net weight loss during the trial. Control ducklings did not become infected and did not have clinical disease. Infected ducklings with clinical disease had pathologic lesions consistent with those observed during natural mortality events. WFBV was reisolated from 37.5% of the inoculated ducklings. Ducklings surviving to 5 days postinoculation developed serum antibody titers to WFBV.


Asunto(s)
Anticuerpos Antivirales/biosíntesis , Enfermedades de las Aves/virología , Patos/virología , Necrosis/veterinaria , Infecciones por Orthomyxoviridae/veterinaria , Orthomyxoviridae/fisiología , Animales , Bahías , Enfermedades de las Aves/inmunología , Enfermedades de las Aves/patología , Modelos Animales de Enfermedad , Patos/inmunología , Intestinos/inmunología , Intestinos/patología , Intestinos/virología , Hígado/inmunología , Hígado/patología , Hígado/virología , Massachusetts , Necrosis/inmunología , Necrosis/patología , Necrosis/virología , Orthomyxoviridae/patogenicidad , Infecciones por Orthomyxoviridae/inmunología , Infecciones por Orthomyxoviridae/patología , Infecciones por Orthomyxoviridae/virología , Páncreas/inmunología , Páncreas/patología , Páncreas/virología , Bazo/inmunología , Bazo/patología , Bazo/virología , Pérdida de Peso
5.
Nature ; 471(7338): 349-52, 2011 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-21412336

RESUMEN

'Hyperthermals' are intervals of rapid, pronounced global warming known from six episodes within the Palaeocene and Eocene epochs (∼65-34 million years (Myr) ago). The most extreme hyperthermal was the ∼170 thousand year (kyr) interval of 5-7 °C global warming during the Palaeocene-Eocene Thermal Maximum (PETM, 56 Myr ago). The PETM is widely attributed to massive release of greenhouse gases from buried sedimentary carbon reservoirs, and other, comparatively modest, hyperthermals have also been linked to the release of sedimentary carbon. Here we show, using new 2.4-Myr-long Eocene deep ocean records, that the comparatively modest hyperthermals are much more numerous than previously documented, paced by the eccentricity of Earth's orbit and have shorter durations (∼40 kyr) and more rapid recovery phases than the PETM. These findings point to the operation of fundamentally different forcing and feedback mechanisms than for the PETM, involving redistribution of carbon among Earth's readily exchangeable surface reservoirs rather than carbon exhumation from, and subsequent burial back into, the sedimentary reservoir. Specifically, we interpret our records to indicate repeated, large-scale releases of dissolved organic carbon (at least 1,600 gigatonnes) from the ocean by ventilation (strengthened oxidation) of the ocean interior. The rapid recovery of the carbon cycle following each Eocene hyperthermal strongly suggests that carbon was re-sequestered by the ocean, rather than the much slower process of silicate rock weathering proposed for the PETM. Our findings suggest that these pronounced climate warming events were driven not by repeated releases of carbon from buried sedimentary sources, but, rather, by patterns of surficial carbon redistribution familiar from younger intervals of Earth history.


Asunto(s)
Atmósfera/química , Ciclo del Carbono , Calentamiento Global/historia , Agua de Mar/química , Océano Atlántico , Foraminíferos/metabolismo , Sedimentos Geológicos/química , Historia Antigua , Océanos y Mares , Temperatura
6.
J Virol ; 89(2): 1389-403, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25392223

RESUMEN

UNLABELLED: Since 1998, cyclic mortality events in common eiders (Somateria mollissima), numbering in the hundreds to thousands of dead birds, have been documented along the coast of Cape Cod, MA, USA. Although longitudinal disease investigations have uncovered potential contributing factors responsible for these outbreaks, detecting a primary etiological agent has proven enigmatic. Here, we identify a novel orthomyxovirus, tentatively named Wellfleet Bay virus (WFBV), as a potential causative agent of these outbreaks. Genomic analysis of WFBV revealed that it is most closely related to members of the Quaranjavirus genus within the family Orthomyxoviridae. Similar to other members of the genus, WFBV contains an alphabaculovirus gp64-like glycoprotein that was demonstrated to have fusion activity; this also tentatively suggests that ticks (and/or insects) may vector the virus in nature. However, in addition to the six RNA segments encoding the prototypical structural proteins identified in other quaranjaviruses, a previously unknown RNA segment (segment 7) encoding a novel protein designated VP7 was discovered in WFBV. Although WFBV shows low to moderate levels of sequence similarity to Quaranfil virus and Johnston Atoll virus, the original members of the Quaranjavirus genus, additional antigenic and genetic analyses demonstrated that it is closely related to the recently identified Cygnet River virus (CyRV) from South Australia, suggesting that WFBV and CyRV may be geographic variants of the same virus. Although the identification of WFBV in part may resolve the enigma of these mass mortality events, the details of the ecology and epidemiology of the virus remain to be determined. IMPORTANCE: The emergence or reemergence of viral pathogens resulting in large-scale outbreaks of disease in humans and/or animals is one of the most important challenges facing biomedicine. For example, understanding how orthomyxoviruses such as novel influenza A virus reassortants and/or mutants emerge to cause epidemic or pandemic disease is at the forefront of current global health concerns. Here, we describe the emergence of a novel orthomyxovirus, Wellfleet Bay virus (WFBV), which has been associated with cyclic large-scale bird die-offs in the northeastern United States. This initial characterization study provides a foundation for further research into the evolution, epidemiology, and ecology of newly emerging orthomyxoviruses, such as WFBV, and their potential impacts on animal and/or human health.


Asunto(s)
Enfermedades de las Aves/epidemiología , Enfermedades de las Aves/mortalidad , Brotes de Enfermedades , Infecciones por Orthomyxoviridae/epidemiología , Infecciones por Orthomyxoviridae/mortalidad , Orthomyxoviridae/aislamiento & purificación , Animales , Anseriformes , Enfermedades de las Aves/patología , Enfermedades de las Aves/virología , Análisis por Conglomerados , Femenino , Masculino , Modelos Moleculares , Datos de Secuencia Molecular , New England/epidemiología , Orthomyxoviridae/clasificación , Orthomyxoviridae/genética , Infecciones por Orthomyxoviridae/patología , Infecciones por Orthomyxoviridae/virología , Filogenia , Conformación Proteica , ARN Viral/genética , Análisis de Secuencia de ADN , Proteínas Virales/química , Proteínas Virales/genética
7.
J Zoo Wildl Med ; 47(4): 1000-1012, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28080899

RESUMEN

Clinical pathology and nutritional parameters are useful in evaluating and monitoring threatened and endangered wildlife populations, but reference ranges for most snake species are lacking. From 2001 to 2005, health assessments were performed on 58 eastern indigo snakes (EIS) (Drymarchon couperi) captured in the wild in southeastern Georgia, United States. Health and nutritional assessments performed included hematology, serum biochemistry, fat-soluble vitamins, heavy metals, pesticide contaminants, parasitology, and surveys of other pathogens. Significant differences in total solids, packed cell volume, glucose, blood urea nitrogen, albumin : globulin ratio, amylase, triglycerides, and bile acids between males and females were observed. Additionally, there was a significant difference between liver and kidney concentrations for vitamins A and E. As previously noted in captive EIS, total Ca was elevated in comparison to concentrations reported in other snake species. Parasitism was a common finding in sampled EIS, but the overall health status of this free-ranging population appeared good. A winter-time dermatitis was found in most snakes, which resolved in the summer months. This study represents the first health and nutritional assessment of free-ranging EIS, and provides needed data to guide monitoring and conservation efforts.


Asunto(s)
Distribución Animal , Animales Salvajes , Estado Nutricional/fisiología , Serpientes/fisiología , Alanina Transaminasa/sangre , Animales , Aspartato Aminotransferasas/sangre , Glucemia , Estudios Transversales , Electrólitos/sangre , Femenino , Georgia , Masculino , Valores de Referencia , Seroglobulinas , Serpientes/sangre , Ácido Úrico/sangre
8.
Avian Pathol ; 44(3): 169-74, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25695149

RESUMEN

Influenza A viruses (IAVs) and avian paramyxoviruses (APMVs) are important pathogens of poultry worldwide, and both commonly occur in wild waterfowl, especially ducks in the family Anatidae. Although wood ducks (Aix sponsa) are members of the Anatidae, their behaviour differs from most other species in this family, which could affect the transmission of IAVs and APMVs. We collected cloacal and oropharyngeal swab and blood samples from more than 700 wood ducks across nine states in the eastern United States of America. No IAVs were isolated, and based on blocking enzyme-linked immunoassay ELISA results, antibodies to IAVs were only detected in 0.2% of samples. In contrast, 23 (3%) APMVs were isolated (22 Newcastle disease virus and 1 APMV-6), and antibodies to multiple serotypes of APMVs were detected in more than 60% of the samples. After-hatch-year birds were more likely to be antibody positive for APMV-4 and APMV-6 compared to hatch-year birds. Female birds were more likely to be antibody positive for APMV-4 than were male birds. Our results indicate that wood ducks are probably not an important host for IAV but are frequently infected with APMVs.


Asunto(s)
Infecciones por Avulavirus/veterinaria , Avulavirus/genética , Reservorios de Enfermedades/veterinaria , Patos/virología , Virus de la Influenza A/genética , Gripe Aviar/virología , Animales , Infecciones por Avulavirus/virología , Cloaca/virología , Cartilla de ADN/genética , Femenino , Modelos Logísticos , Masculino , Mid-Atlantic Region , New England , Orofaringe/virología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Pruebas Serológicas/veterinaria , Sudeste de Estados Unidos
9.
Curr Top Microbiol Immunol ; 365: 31-47, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-22911439

RESUMEN

The renewed interest in the concept of One Health has occurred as a result of the increased emergence of zoonotic infectious diseases over the past decade. The subsequent impacts of these diseases on human, livestock, and wildlife health, as well as the economic effects, have given international health organizations and national governments a greater appreciation of the importance of collaborative efforts in solving health problems. The One Health concept is not new, but under its umbrella, a new generation of veterinarians, physicians, ecologists, biologists, and social scientists is shaping the concept in novel ways. This has led to increased support for One Health initiatives to control disease by international agencies, national governments, and nongovernmental organizations as well as a growing emphasis on One Health concepts in training the veterinary workforce. Veterinary schools are reorganizing veterinary education to better teach students the precepts of One Health. This chapter explores the evolution and application of the One Health concept from the perspective of the veterinarian. The veterinary profession is positioned to be a strong advocate and leader of One Health. Veterinarians have a long history of involvement with One Health activities, and this involvement has adjusted and shifted with the changing needs of society. A new area of work for veterinarians is ecosystem health, which is becoming more relevant as a result of the impact that the ever-increasing human population is having on the environment that supports them.


Asunto(s)
Enfermedades Transmisibles Emergentes/prevención & control , Rol Profesional , Veterinarios , Zoonosis/prevención & control , Animales , Ecosistema , Educación en Veterinaria , Humanos , Liderazgo , Salud Pública/educación
10.
J Wildl Dis ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38975743

RESUMEN

Trichomonas gypaetinii was detected in 117 (88%) of 133 Bald Eagles (Haliaceetus leucocephalus) and in 0 of 7 Golden Eagles (Aquila chrysaetos) in the USA, with no sex or age prevalence difference. All eagles lacked associated lesions. This study indicated that T. gypaetinii is common and widespread in Bald Eagles, but rarely associated with disease.

11.
Sci Rep ; 13(1): 191, 2023 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-36604450

RESUMEN

The bald eagle (Haliaeetus leucocephalus) is a culturally and ecologically vital species in North America that embodies conservation success but continues to face threats that include emerging pathogens. The introduction of A/goose/Guangdong/1/1996 lineage highly pathogenic (HP) clade 2.3.4.4b H5N1 influenza A virus (IAV) in North America in late 2021 resulted in high rates of mortality among bald eagles. Here we show an alarming rate of bald eagle nest failure and mortality attributed to HP IAV. We documented fatal, systemic HP IAV infection in breeding adult and nestling bald eagles along the southeastern U.S. coast. Concurrently, annual bald eagle nest surveys in Georgia and Florida revealed a precipitous drop in success in coastal counties compared with previous years, portending negative impacts on population recruitment. As an apex predator and efficient scavenger, it is likely that bald eagles become infected through consumption of infected waterfowl. These results and similar reports of raptor mortality in Europe, Asia, and Africa, indicate a clear threat to raptor health. The possible long-term persistence of HP H5N1 IAV in North America poses an impending threat to bald eagle populations not only related to direct mortality but also decreased recruitment and warrants continued efforts to understand these potential impacts.


Asunto(s)
Águilas , Subtipo H5N1 del Virus de la Influenza A , Animales , América del Norte/epidemiología , Florida , Georgia
12.
J Wildl Dis ; 59(4): 590-600, 2023 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-37578749

RESUMEN

A Eurasian lineage highly pathogenic avian influenza virus (HPAIV) of the clade 2.3.4.4b (Goose/Guangdong lineage) was detected in migratory bird populations in North America in December 2021, and it, along with its reassortants, have since caused wild and domestic bird outbreaks across the continent. Relative to previous outbreaks, HPAIV cases among wild birds in 2022 exhibited wider geographic extent within North America and higher levels of mortality, suggesting the potential for population-level impacts. Given the possible conservation implications of HPAIV in wild birds, natural resource managers have sought guidance on actions that may mitigate negative effects of disease among North American bird populations, including modification of existing management practices. Banding of waterfowl is a critical tool for population management for several harvested species in North America, but some banding techniques, such as bait trapping, can lead to increased congregation of waterfowl, potentially altering HPAIV transmission. We used an expert opinion exercise to assess how bait trapping of dabbling ducks in Canada may influence HPAIV transmission and wild bird health. The expert group found that it is moderately likely that bait trapping of dabbling ducks in wetlands will significantly increase the transmission of HPAIV among individual ducks, but there is a low probability that this will result in significant population-level effects on North American dabbling ducks. Considering the lack of empirical work studying how capture and handling methods may change transmission of HPAIV among waterfowl, as well as the importance of bait trapping for waterfowl management in North America, future work should focus on filling knowledge gaps pertaining to the influence of baiting on HPAIV occurrence to better inform banding procedures and management decision making.


Asunto(s)
Virus de la Influenza A , Gripe Aviar , Animales , Gripe Aviar/epidemiología , Patos , Testimonio de Experto , Animales Salvajes , Aves
13.
PLoS One ; 16(4): e0246134, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33826627

RESUMEN

Raptors, including eagles, are geographically widespread and sit atop the food chain, thereby serving an important role in maintaining ecosystem balance. After facing population declines associated with exposure to organochlorine insecticides such as dichlorodiphenyltrichloroethane (DDT), bald eagles (Haliaeetus leucocephalus) have recovered from the brink of extinction. However, both bald and golden eagles (Aquila chrysaetos) are exposed to a variety of other toxic compounds in the environment that could have population impacts. Few studies have focused on anticoagulant rodenticide (AR) exposure in eagles. Therefore, the purpose of this study was to determine the types of ARs that eagles are exposed to in the USA and better define the extent of toxicosis (i.e., fatal illness due to compound exposure). Diagnostic case records from bald and golden eagles submitted to the Southeastern Cooperative Wildlife Disease Study (University of Georgia) 2014 through 2018 were reviewed. Overall, 303 eagles were examined, and the livers from 116 bald eagles and 17 golden eagles were tested for ARs. The percentage of AR exposure (i.e., detectable levels but not associated with mortality) in eagles was high; ARs were detected in 109 (82%) eagles, including 96 (83%) bald eagles and 13 (77%) golden eagles. Anticoagulant rodenticide toxicosis was determined to be the cause of mortality in 12 (4%) of the 303 eagles examined, including 11 bald eagles and 1 golden eagle. Six different AR compounds were detected in these eagles, with brodifacoum and bromadiolone most frequently detected (81% and 25% of eagles tested, respectively). These results suggest that some ARs, most notably brodifacoum, are widespread in the environment and are commonly consumed by eagles. This highlights the need for research to understand the pathways of AR exposure in eagles, which may help inform policy and regulatory actions to mitigate AR exposure risk.


Asunto(s)
4-Hidroxicumarinas/efectos adversos , Anticoagulantes/efectos adversos , Enfermedades de las Aves , Águilas/metabolismo , Rodenticidas/efectos adversos , Animales , Enfermedades de las Aves/inducido químicamente , Enfermedades de las Aves/metabolismo , Enfermedades de las Aves/patología , Ecosistema , Hígado/metabolismo , Hígado/patología , Estados Unidos
14.
Sci Adv ; 6(44)2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-33127682

RESUMEN

The end-Cretaceous bolide impact triggered the devastation of marine ecosystems. However, the specific kill mechanism(s) are still debated, and how primary production subsequently recovered remains elusive. We used marine plankton microfossils and eco-evolutionary modeling to determine strategies for survival and recovery, finding that widespread phagotrophy (prey ingestion) was fundamental to plankton surviving the impact and also for the subsequent reestablishment of primary production. Ecological selectivity points to extreme post-impact light inhibition as the principal kill mechanism, with the marine food chain temporarily reset to a bacteria-dominated state. Subsequently, in a sunlit ocean inhabited by only rare survivor grazers but abundant small prey, it was mixotrophic nutrition (autotrophy and heterotrophy) and increasing cell sizes that enabled the eventual reestablishment of marine food webs some 2 million years later.

15.
Int J Vitam Nutr Res ; 79(3): 180-7, 2009 May.
Artículo en Inglés | MEDLINE | ID: mdl-20209469

RESUMEN

Serum concentrations of 25-hydroxyvitamin D [25(OH)D] were determined for free-ranging and captive white-tailed deer (WTD). Effects of gender, season, and age on 25(OH)D concentrations were determined as well as comparisons to concentrations in serum from captive reindeer and elk. Seasonal variations in 25(OH)D concentrations were detected for both captive and free-ranging WTD with greatest concentrations detected in August/September (approximately 25 ng/mL) and lowest concentrations in February (approximately 5 - 10 ng/mL). Free-ranging WTD < 1 year of age had lower 25(OH)D concentrations (approximately 6 ng/mL) than did free-ranging WTD > 1 year of age (approximately12 ng/mL). For captive WTD fawns, 25(OH)D concentrations increased from 1 to 9 days of age (exceeding 100 ng/mL) and then steadily declined to approximately 10 ng/mL by 3 months of age. In general, differences in 25(OH)D concentrations based on gender were not detected. 25(OH)D concentrations in captive WTD did not differ from that of captive reindeer; yet, 25(OH)D concentrations were lower in WTD than in captive elk. Additional research is necessary to determine if low serum 25(OH)D concentrations during the winter or pre-weaning period are associated with increased rates of infectious and metabolic disease.


Asunto(s)
Ciervos/sangre , Vitamina D/análogos & derivados , Factores de Edad , Animales , Animales Recién Nacidos , Animales Salvajes , Femenino , Masculino , Estaciones del Año , Factores Sexuales , Estados Unidos , Vitamina D/sangre
16.
J Am Vet Med Assoc ; 255(8): 908-914, 2019 10 15.
Artículo en Inglés | MEDLINE | ID: mdl-31573861

RESUMEN

On September 30, 2016, the US National Veterinary Services Laboratory confirmed an autochthonous case of New World screwworm infestation in a Key deer (Odocoileus virginianus clavium) from Big Pine Key, Fla. This case marked the first identification of a sustained and reproducing population of New World screwworm flies in the United States since 1966. Multiple federal, state, and local government agencies collaborated to initiate a response to the outbreak. Efforts were successful in eradicating the flies from Florida.


Asunto(s)
Ciervos , Dípteros , Animales , Brotes de Enfermedades , Florida
17.
Ecol Appl ; 18(5): 1083-92, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18686573

RESUMEN

Urbanization is a widespread phenomenon that is likely to influence the prevalence and impact of wildlife pathogens, with implications for wildlife management and public health policies toward zoonotic pathogens. In this study, wild songbird populations were sampled at 14 sites along an urban rural gradient in the greater metropolitan Atlanta (Georgia, USA) area and tested for antibodies to West Nile virus (WNV). The level of urbanization among sites was quantitatively assessed using a principal component analysis of key land use characteristics. In total, 499 individual birds were tested during the spring and summer over three years (2004-2006). Antibody prevalence of WNV increased from rural to urban sites, and this trend was stronger among adult birds relative to juveniles. Furthermore, antibody prevalence among Northern Cardinals (Cardinalis cardinalis) was significantly higher than in other songbird species along the urban gradient. Findings reported here indicate that ecological factors associated with urbanization can influence infection patterns of this vector-borne viral disease, with likely mechanisms including changes in host species diversity and the tolerance or recovery of infected animals.


Asunto(s)
Pájaros Cantores/virología , Urbanización , Virus del Nilo Occidental/aislamiento & purificación , Animales , Anticuerpos Antivirales/análisis , Estudios Seroepidemiológicos , Estados Unidos , Virus del Nilo Occidental/inmunología
18.
J Wildl Dis ; 44(3): 670-86, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18689653

RESUMEN

The Alligator Snapping Turtle (Macrochelys temminckii) is a large freshwater turtle endemic to river systems that drain into the Gulf of Mexico. Turtle populations were sharply reduced by commercial harvest in the 1970s and 1980s; however, the species has yet to be protected under the Endangered Species Act. While anthropogenic stressors such as habitat fragmentation and degradation and illegal capture continue to threaten populations, the degree to which disease may be contributing to any decline of the Alligator Snapping Turtle is unknown. Data were collected from 97 free-ranging Alligator Snapping Turtles in nine waterways in Florida and Georgia from 2001 to 2006. Eleven turtles were captured more than once, resulting in a total sample pool of 123. Reference ranges were established for complete blood count, plasma biochemistry values, trace metals (mercury, zinc, copper, lead, and arsenic), and nutrient parameters (vitamins A, E, D, and selenium). Variations by capture location, sex, and season were detected and likely resulted from external factors such as habitat and diet. Turtles sampled in one location were positive for tortoise herpesviral antibodies. Blood mercury values also differed among populations. This study provides justification for the use of these long-lived aquatic turtles as biologic monitors of the health of local freshwater ecosystems.


Asunto(s)
Conservación de los Recursos Naturales , Ecosistema , Estado de Salud , Tortugas/sangre , Tortugas/fisiología , Animales , Análisis Químico de la Sangre/veterinaria , Femenino , Florida/epidemiología , Georgia/epidemiología , Masculino , Valores de Referencia , Estaciones del Año , Factores Sexuales
19.
Avian Dis ; 51(1): 125-8, 2007 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-17461278

RESUMEN

Crows have been the centerpiece of avian West Nile virus (WNV) surveillance and research in North America. This work has demonstrated variation in susceptibility to WNV infection between American (Cor vus brachyrhynchos) andFish Crows (Corvus ossifragus). The higher WNV-associated mortality rate in American Crows compared with Fish Crows suggests that WNV antibody prevalence would be greater in the Fish Crow population. The objectives of this study were to 1) determine whether Fish Crows had higher WNV antibody prevalencethan American Crows, 2 ) determine th e persistence o f antibodies to WNV in naturally infected Fish Crows, and 3) develop a technique to distinguish Fish Crows from American Crows on the basis of sequence analysis and restriction enzyme digestion of a mitochondrial DNA fragment. West Nile virus antibody prevalence was 16.5% (n = 97) in Fish Crows and 5.7% in American Crows (n = 53) collected from Georgia between 2004 and 2006. Antibodies persisted at high titers for 12 mo in Fish Crows. This is the first report of WNV antibody persistence in a crow species. A polymerase chain reaction technique paired with restriction enzyme digestion easily distinguished American Crows from Fish Crows on the basis of a mitochondrial DNA fragment.


Asunto(s)
Anticuerpos Antivirales/sangre , Enfermedades de las Aves/inmunología , Enfermedades de las Aves/virología , Cuervos/inmunología , Cuervos/virología , Fiebre del Nilo Occidental/veterinaria , Virus del Nilo Occidental/inmunología , Animales , Secuencia de Bases , Enfermedades de las Aves/epidemiología , Cuervos/genética , ADN Mitocondrial/genética , Georgia/epidemiología , Reacción en Cadena de la Polimerasa/veterinaria , Especificidad de la Especie , Fiebre del Nilo Occidental/epidemiología , Fiebre del Nilo Occidental/inmunología , Fiebre del Nilo Occidental/virología , Virus del Nilo Occidental/genética , Virus del Nilo Occidental/aislamiento & purificación
20.
J Wildl Dis ; 43(1): 129-35, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17347403

RESUMEN

Mourning doves (Zenaida macroura) are the most abundant and widespread native member of the columbid family, as well as a major migratory game species, in the United States. However, there is little information on mortality factors in mourning doves. Records of necropsy accessions at the Southeastern Cooperative Wildlife Disease Study (SCWDS) from 15 southeastern states, from 1971 through 2005, were reviewed. One hundred thirty-five mourning doves were submitted from nine states during the 35-yr period. Trichomonosis constituted 40% (n = 54) of all diagnoses and was the most frequent diagnosis. Toxicoses and avian pox constituted 18.5% (n = 25) and 14.8% (n = 20) of all diagnoses, respectively. Remaining diagnoses included trauma, suspected toxicosis, Ascaridia columbae infection, suspected tick paralysis, and undetermined. Adults were observed more frequently with trichomonosis (94.1%) and toxicoses (68%) as compared to juveniles, but a gender predisposition was not apparent for either disease. Age and gender predilections were not apparent for cases of avian pox. The majority of the trichomonosis and avian pox cases were observed in the spring-summer, whereas the majority of the toxicosis cases were observed in the winter-spring. Additionally, the Georgia Department of Human Resources-Division of Public Health and West Virginia Department of Health and Human Resources submitted 809 mourning doves to SCWDS from 2001 through 2005 for West Nile virus surveillance efforts. West Nile virus was isolated from 2.1% (n = 17) and eastern equine encephalitis virus (EEEV) was isolated from 0.2% (n = 2) of the submitted birds.


Asunto(s)
Infecciones por Arbovirus/veterinaria , Arbovirus/aislamiento & purificación , Enfermedades de las Aves/epidemiología , Columbidae/virología , Virosis/veterinaria , Factores de Edad , Animales , Infecciones por Arbovirus/epidemiología , Infecciones por Arbovirus/patología , Enfermedades de las Aves/patología , Virus de la Encefalitis Equina del Este/aislamiento & purificación , Femenino , Masculino , Estaciones del Año , Vigilancia de Guardia/veterinaria , Factores Sexuales , Sudeste de Estados Unidos/epidemiología , Tricomoniasis/epidemiología , Tricomoniasis/veterinaria , Virosis/epidemiología , Virosis/patología , Virus del Nilo Occidental/aislamiento & purificación
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