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Debra L Miller - One of the best experts on this subject based on the ideXlab platform.
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influence of herbicide exposure and Ranavirus Infection on growth and survival of juvenile red eared slider turtles trachemys scripta elegans
Viruses, 2021Co-Authors: Rachel M Goodman, Edward Davis Carter, Debra L MillerAbstract:Ranaviruses are an important wildlife pathogen of fish, amphibians, and reptiles. Previous studies have shown that susceptibility and severity of Infection can vary with age, host species, virus strain, temperature, population density, and presence of environmental stressors. Experiments are limited with respect to interactions between this pathogen and environmental stressors in reptiles. In this study, we exposed hatchling red-eared slider turtles (Trachemys scripta elegans) to herbicide and Ranavirus treatments to examine direct effects and interactions on growth, morbidity, and mortality. Turtles were assigned to one of three herbicide treatments or a control group. Turtles were exposed to atrazine, Roundup ProMax®, or Rodeo® via water bath during the first 3 weeks of the experiment. After 1 week, turtles were exposed to either a control (cell culture medium) or Ranavirus-infected cell lysate via injection into the pectoral muscles. Necropsies were performed upon death or upon euthanasia after 5 weeks. Tissues were collected for histopathology and detection of Ranavirus DNA via quantitative PCR. Only 57.5% of turtles exposed to Ranavirus tested positive for ranaviral DNA at the time of death. Turtles exposed to Ranavirus died sooner and lost more mass and carapace length, but not plastron length, than did controls. Exposure to environmentally relevant concentrations of herbicides did not impact Infection rate, morbidity, or mortality of hatchling turtles due to Ranavirus exposure. We also found no direct effects of herbicide or interactions with Ranavirus exposure on growth or survival time. Results of this study should be interpreted in the context of the modest Ranavirus Infection rate achieved, the general lack of growth, and the unplanned presence of an additional pathogen in our study.
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Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed without changing gloves at four known Ranavirus Infection prevalence levels.
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed without changing gloves at four known Ranavirus Infection prevalence levels.
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Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were co-housed with infected tadpoles at three known Ranavirus Infection prevalence levels.
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were co-housed with infected tadpoles at three known Ranavirus Infection prevalence levels.
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Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed with and without changing gloves (yes, no) at two known Ranavirus Infection prevalence levels (10%, 40%).
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed with and without changing gloves (yes, no) at two known Ranavirus Infection prevalence levels (10%, 40%).
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The difference in the instantaneous rate of mortality (i.e., hazard ratio) for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed without changing gloves at four known Ranavirus Infection prevalence levels.
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:The difference in the instantaneous rate of mortality (i.e., hazard ratio) for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed without changing gloves at four known Ranavirus Infection prevalence levels.
Matthew J Gray - One of the best experts on this subject based on the ideXlab platform.
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cmtv like Ranavirus Infection associated with high mortality in captive catfish like loach triplophysa siluorides in china
Transboundary and Emerging Diseases, 2020Co-Authors: Lishuang Deng, Matthew J Gray, Yi Geng, Xiaoli Huang, Defang Chen, Ruoxuan Zhao, Kaiyu Wang, Ping Ouyang, Zhengli Chen, Chao HuangAbstract:Ranaviruses are important emerging pathogens of ectothermic vertebrates that threaten aquaculture and wildlife worldwide. A mortality event occurred in a cultured population of catfish-like loach (Triplophysa siluorides) in Sichuan Province, China. Gross clinical signs of the affected fish included skin lesions and haemorrhagic ulcers, which are often associated with Ranaviruses. Inoculation of liver, kidney and spleen tissue homogenates in epithelioma papulosum cyprini (EPC) cells at 25°C resulted in cytopathic effect within 24 hr. Transmission electron microscopy of infected EPC cells revealed hexagonal viral arrays in the cytoplasm and icosahedral geometry of the virions. Following exposure of T. siluroides to the isolated virus, similar clinical signs were observed and the fish experienced 40% and 90% mortality after 21 days at 103.58 and 107.8 TCID50 /0.1 ml doses, respectively, providing evidence the isolated virus was the main causative agent of the mortality event. Diagnostic PCR of the major capsid protein gene of Ranavirus showed that all samples of diseased fish and isolated virus were positive. Phylogenetic analysis revealed that the isolated virus, designated as FYLl40220, was associated with the Common Midwife Toad Virus (CMTV)-like Ranavirus clade. To our knowledge, this case represents the first report of CMTV-associated mortality in a fish species. Collectively, these results suggest that the host range of CMTV-like Ranaviruses is greater than previously thought, and this clade of Ranaviruses could have significant economic and biodiversity impacts.
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Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed without changing gloves at four known Ranavirus Infection prevalence levels.
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed without changing gloves at four known Ranavirus Infection prevalence levels.
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Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were co-housed with infected tadpoles at three known Ranavirus Infection prevalence levels.
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were co-housed with infected tadpoles at three known Ranavirus Infection prevalence levels.
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Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed with and without changing gloves (yes, no) at two known Ranavirus Infection prevalence levels (10%, 40%).
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed with and without changing gloves (yes, no) at two known Ranavirus Infection prevalence levels (10%, 40%).
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The difference in the instantaneous rate of mortality (i.e., hazard ratio) for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed without changing gloves at four known Ranavirus Infection prevalence levels.
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:The difference in the instantaneous rate of mortality (i.e., hazard ratio) for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed without changing gloves at four known Ranavirus Infection prevalence levels.
Matthew C. Allender - One of the best experts on this subject based on the ideXlab platform.
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temperature affects the host hematological and cytokine response following experimental Ranavirus Infection in red eared sliders trachemys scripta elegans
PLOS ONE, 2020Co-Authors: Jeremy M Rayl, Matthew C. AllenderAbstract:Pathogen-host interactions are important components of epidemiological research, but are scarcely investigated in chelonians. Red-eared sliders (Trachemys scripta elegans), are recognized as a model for frog virus-3 Infection (FV3), a Ranavirus in the family Iridoviridae that infects multiple classes of ectothermic vertebrates. Previous challenge studies observed differences in disease outcome based on environmental temperature in this species, but the host response was minimally evaluated. We challenged red-eared sliders with an FV3-like Ranavirus at both 28°C and 22°C. We monitored several host response variables for 30 days, including: survival (binary outcome and duration), clinical signs, total and differential leukocytes, and select cytokine transcription in the buffy coat (IL-1β, TNFα, IFYg, IL-10). After 30 days, 17% of challenged turtles survived at 28°C (Median survival time [MST]: 15 days, range: 10-30 days) and 50% survived (MST: 28.5 days, range: 23-30 days) at 22°C (range 23-30 days). The most common clinical signs were injection site swelling, palpebral swelling, and lethargy. The heterophil/lymphocyte ratio at 22°C and interleukin-1 beta (IL1β) transcription at both 22°C and 28°C were significantly greater on days 9, 16, and 23 in FV3 challenged groups. Tumor necrosis factor alpha and interleukin-10 were transcribed at detectable levels, but did not display significant differences in mean relative transcription quantity over time. Overall, evidence indicates an over-robust immune response leading to death in the challenged turtles. FV3 remains a risk for captive and free-ranging chelonian populations, and insight to host/pathogen interaction through this model helps to elucidate the timing and intensity of the host response that contribute to mortality.
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Pathogen Surveillance and Detection of Ranavirus (Frog virus 3) in Translocated Gopher Tortoises (Gopherus polyphemus)
Journal of wildlife diseases, 2020Co-Authors: Rebecca A. Cozad, Matthew C. Allender, Terry M. Norton, Matthew J Aresco, Sonia M. HernandezAbstract:Emerging pathogens may pose additional threats to already vulnerable populations of chelonians, such as gopher tortoises (Gopherus polyphemus). In response to a mortality event on a translocation site in northwest Florida, US during 2013-15, 13 gopher tortoises were necropsied and their tissues were screened for 12 pathogens, including Mycoplasma agassizii, Mycoplasma testudineum, and Frog virus 3-like Ranavirus (FV3). The DNA of FV3 was detected via quantitative PCR in the gastrointestinal tract of three tortoises. Subsequently, pathogen surveillance was performed on whole blood and oral-cloacal swab samples of live translocated tortoises from two different enclosures within the site (n=68), rehabilitated tortoises from the site (n=18), and tortoises prior to release on site (n=35) during 2015-17. Mycoplasma spp. were present in all groups and years of live tortoises tested. The DNA of FV3 was detected in 15 individuals both with and without clinical signs of disease in 2016. We recaptured 20 tortoises and captured an additional 20 tortoises in 2017 for surveillance, yet FV3 DNA was no longer detected, even in those that had previously tested positive (n=7). The results of this study contribute to the epidemiology of Ranavirus in chelonians and suggests that gopher tortoises could be reservoirs for FV3. We recommend that the status of Ranavirus Infection should be included for health screens for gopher tortoises in translocation programs.
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Fatal Ranavirus Infection in a group of zoo-housed meller's chameleons (trioceros melleri)
Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians, 2019Co-Authors: Lauren B. Peiffer, Matthew C. Allender, Allan P. Pessier, Kuttichantran Subramaniam, Thomas B Waltzek, Samantha J. Sander, Kathleen L. Gabrielson, Natalie K. Stilwell, Laura Adamovicz, Ellen BronsonAbstract:A group of five juvenile Meller's chameleons (Trioceros melleri) experienced 100% mortality over a period of 1 mo due to Ranavirus Infection. The index case was found dead without premonitory signs. The three subsequent cases presented with nonspecific clinical signs (lethargy, decreased appetite, ocular discharge) and were ultimately euthanatized. The final case died after initially presenting with skin lesions. Postmortem examination revealed thin body condition in all five animals and mild coelomic effusion and petechiae affecting the tongue and kidneys of one animal. Microscopically, all animals had multifocal necrosis of the spleen, liver, and kidney; four of five animals had necrosis of the nasal cavity; and two of five had necrosis of adrenal tissue, bone marrow, and skin. Numerous basophilic intracytoplasmic inclusions were present in the liver of all animals and nasal mucosa of three of the five animals. Consensus polymerase chain reaction for herpesvirus and adenovirus were negative, whereas Ranavirus quantitative polymerase chain reaction was positive. Virus isolation followed by whole genome sequencing and Bayesian phylogenetic analysis classified the isolates as a strain of frog virus 3 (FV3) most closely related to an FV3 isolate responsible for a previous outbreak in the zoo's eastern box turtle (Terrapene carolina carolina) group. This case series documents the first known occurrence of Ranavirus-associated disease in chameleons and demonstrates the potential for interspecies transmission between chelonian and squamate reptiles.
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EXPERIMENTAL CHALLENGE STUDY OF FV3-LIKE Ranavirus Infection IN PREVIOUSLY FV3-LIKE Ranavirus INFECTED EASTERN BOX TURTLES (TERRAPENE CAROLINA CAROLINA) TO ASSESS Infection AND SURVIVAL.
Journal of zoo and wildlife medicine : official publication of the American Association of Zoo Veterinarians, 2015Co-Authors: Jennifer C. Hausmann, Matthew C. Allender, Allison N. Wack, Mike R. Cranfield, Kevin J. Murphy, Kevin Barrett, Jennell L. Romero, James F. X. Wellehan, Stella A. Blum, M. Christine ZinkAbstract:The Maryland Zoo in Baltimore experienced an outbreak of Frog virus-3 (FV3)-like Ranavirus during the summer of 2011, during which 14 of 27 (52%) of its captive eastern box turtles (Terrapene carolina carolina) survived. To assess survival, immunity, and viral shedding, an experimental challenge study was performed in which the surviving, previously infected turtles were reinfected with the outbreak strain of FV3-like Ranavirus. Seven turtles were inoculated with virus intramuscularly and four control turtles received saline intramuscularly. The turtles were monitored for 8 wk with blood and oral swabs collected for quantitative polymerase chain reaction (qPCR). During that time, one of seven (14%) inoculated turtles and none of the controls (0%) died; there was no significant difference in survival. Clinical signs of the inoculated turtles, except for the turtle that died, were mild compared to the original outbreak. Quantitative PCR for FV3-like Ranavirus on blood and oral swabs was positive for all inoculated turtles and negative for all controls. The turtle that died had intracytoplasmic inclusion bodies in multiple organs. Three inoculated and two control turtles were euthanized at the end of the study. No inclusion bodies were present in any of the organs. Quantitative PCR detected FV3-like Ranavirus in the spleen of a control turtle, which suggested persistence of the virus. The surviving five turtles were qPCR-negative for FV3-like Ranavirus from blood and oral swabs after brumation. Quantitative PCR for Terrapene herpesvirus 1 found no association between Ranavirus Infection and herpesvirus loads. In conclusion, previously infected eastern box turtles can be reinfected with the same strain of FV3-like Ranavirus and show mild to no clinical signs but can shed the virus from the oral cavity.
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distribution and host range of Ranaviruses
2015Co-Authors: Amanda L J Duffus, Matthew C. Allender, Anke C. Stöhr, Thomas B Waltzek, Michael Gotesman, Richard J Whittington, Paul Hick, Megan K Hines, Rachel E. MarschangAbstract:Ranaviruses are globally distributed pathogens in amphibian, fish, and reptile communities that appear to be emerging. Cases of Ranavirus Infection or disease have been confirmed in at least 105 amphibian species (18 families), 41 fish species (22 families), and 29 reptile species (12 families). Ranaviruses have been documented on all continents except Antarctica, and are frequently associated with mass die-offs. Host susceptibility differs among species, with some species harboring subclinical Infections and likely serving as reservoirs for the virus, and other highly susceptible species amplifying the virus. Currently, there are six recognized species of Ranavirus, and all are not equally pathogenic among hosts. Frog virus 3 (FV3) is the type species of the genus Ranavirus, and appears to be the most globally distributed species infecting ectothermic taxonomic across three vertebrate classes. International commerce involving subclinically infected ectothermic vertebrates undoubtedly has contributed to the global distribution and emergence of Ranaviruses. Herein, we describe the global distributed species infecting ectothermic vertebrates across three taxonomic classes.
Weiming Lai - One of the best experts on this subject based on the ideXlab platform.
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characterization of a Ranavirus isolated from the chinese giant salamander andrias davidianus blanchard 1871 in china
Aquaculture, 2013Co-Authors: Z Y Zhou, Yi Geng, Xingwei Liu, S Y Ren, Yaojia Zhou, K Y Wang, Xiaoli Huang, Defang Chen, Xi Peng, Weiming LaiAbstract:Abstract In this study, we confirmed that a novel Ranavirus was related to mass die-offs of farmed Chinese giant salamanders ( Andrias davidianus ) in Leshan, Sichuan Province, China. The farmed Chinese giant salamanders presented typical clinical symptoms that included ecchymoses or swollen areas on the head and limbs, necrosis of the limbs, and skin ulceration. Bacteriological and pathologic examinations further proved the possibility of Ranavirus Infection of the Chinese giant salamanders. The virus was isolated via inoculation in the epithelioma papulosum cyprini (EPC) cells. The virus multiplied and caused cytopathogenic effects (CPE) at 25 °C in the EPC cells and it was sensitive to chloroform treatment, trypsinase treatment, heating at 56 °C for 30 min, acidity (pH 3.0), and alkalinity (pH = 10.0). Treatment with 5-bromouracil deoxyriboside (5-BrdU) inhibited viral replication, which suggested that the viral genome contained DNA. After the viral inoculation in the cell, samples were collected and made the ultrathin sections, and then the iridovirus-like particles could be observed in the cytoplasm and nuclei by electron microscopy. Using the isolated viral DNA as the template for PCR, we amplified, cloned, and analyzed target sequences in three different genomic regions, i.e., the major capsid protein (MCP), DNA polymerase, and neurofilament triplet H1-like protein (NF-H1). Subsequent multiple alignment and phylogenetic analysis showed that the newly isolated virus was closely related to KRV-1, soft-shelled turtle iridovirus, Rana grylio iridovirus, and FV3. In the pathogenicity tests, the challenged salamanders showed similar clinical symptoms to the natural Infections. Our data suggested that the virus isolate was a novel member of the genus Ranavirus , family Iridoviridae . We tentatively named the virus as Chinese giant salamander virus (CGSV-L). CGSV-L was able to cause serious systemic disease and it was capable of killing 80% of Chinese giant salamanders (body weight = 300.0 ± 15.0 g).
Jennifer A. Spatz - One of the best experts on this subject based on the ideXlab platform.
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Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed without changing gloves at four known Ranavirus Infection prevalence levels.
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed without changing gloves at four known Ranavirus Infection prevalence levels.
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Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were co-housed with infected tadpoles at three known Ranavirus Infection prevalence levels.
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were co-housed with infected tadpoles at three known Ranavirus Infection prevalence levels.
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Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed with and without changing gloves (yes, no) at two known Ranavirus Infection prevalence levels (10%, 40%).
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:Survival functions for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed with and without changing gloves (yes, no) at two known Ranavirus Infection prevalence levels (10%, 40%).
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The difference in the instantaneous rate of mortality (i.e., hazard ratio) for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed without changing gloves at four known Ranavirus Infection prevalence levels.
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:The difference in the instantaneous rate of mortality (i.e., hazard ratio) for uninfected wood frog (Lithobates sylvaticus) tadpoles that were processed without changing gloves at four known Ranavirus Infection prevalence levels.
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The difference in the instantaneous rate of mortality (i.e., hazard ratio) for uninfected wood frog (Lithobates sylvaticus) tadpoles that were co-housed with infected tadpoles at three durations and three known Ranavirus Infection prevalence levels.
2018Co-Authors: Matthew J Gray, Jennifer A. Spatz, Davis E. Carter, Christian M. Yarber, Rebecca P. Wilkes, Debra L MillerAbstract:The difference in the instantaneous rate of mortality (i.e., hazard ratio) for uninfected wood frog (Lithobates sylvaticus) tadpoles that were co-housed with infected tadpoles at three durations and three known Ranavirus Infection prevalence levels.
