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Jitender P. Dubey - One of the best experts on this subject based on the ideXlab platform.
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Toxoplasmosis in geese and detection of two new atypical Toxoplasma gondii strains from naturally infected Canada geese (Branta Canadensis)
Parasitology Research, 2016Co-Authors: Shiv K. Verma, Rafael Calero-bernal, Camila K. Cerqueira-cézar, Oliver C.h. Kwok, Mike Dudley, Tiantian Jiang, Dolores Hill, Jitender P. DubeyAbstract:Wild birds are important in the epidemiology of toxoplasmosis because they can serve as reservoir hosts, and vectors of zoonotic pathogens including Toxoplasma gondii . Canada goose ( Branta Canadensis ) is the most widespread geese in North America. Little is known concerning T. gondii infection in both migratory, and local resident populations of Canada geese. Here, we evaluated the seroprevalence, isolation, and genetic characterization of viable T. gondii isolates from a migratory population of Canada geese. Antibodies against T. gondii were detected in 12 of 169 Canada geese using the modified agglutination test (MAT, cutoff 1:25). The hearts of 12 seropositive geese were bioassayed in mice for isolation of T. gondii . Viable parasites were isolated from eight. One isolate was obtained from a seropositive goose by both bioassays in mice, and in a cat; the cat fed infected heart excreted T. gondii oocysts. Additionally, one isolate was obtained from a pool of four seronegative ( < 1:25) geese by bioassay in a cat. The T. gondii isolates were further propagated in cell culture, and DNA extracted from cell culture-derived tachyzoites were characterized using 10 polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) genetic markers (SAG1, 5′ and 3′SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). The results revealed five different genotypes. ToxoDB PCR-RFLP genotype #1 (type II) in one isolate, genotype #2 (type III) in four isolates, genotype #4 in two isolates, and two new genotypes (ToxoDB PCR-RFLP genotype #266 in one isolate and #267 in one isolate) were identified. These results indicate genetic diversity of T. gondii strains in the Canada geese, and this migratory bird might provide a mechanism of T. gondii transmission at great distances from where an infection was acquired.
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Toxoplasmosis in geese and detection of two new atypical Toxoplasma gondii strains from naturally infected Canada geese (Branta Canadensis).
Parasitology research, 2016Co-Authors: Shiv K. Verma, Rafael Calero-bernal, Camila K. Cerqueira-cézar, Oliver C.h. Kwok, Mike Dudley, Tiantian Jiang, Dolores E. Hill, Jitender P. DubeyAbstract:Wild birds are important in the epidemiology of toxoplasmosis because they can serve as reservoir hosts, and vectors of zoonotic pathogens including Toxoplasma gondii. Canada goose (Branta Canadensis) is the most widespread geese in North America. Little is known concerning T. gondii infection in both migratory, and local resident populations of Canada geese. Here, we evaluated the seroprevalence, isolation, and genetic characterization of viable T. gondii isolates from a migratory population of Canada geese. Antibodies against T. gondii were detected in 12 of 169 Canada geese using the modified agglutination test (MAT, cutoff 1:25). The hearts of 12 seropositive geese were bioassayed in mice for isolation of T. gondii. Viable parasites were isolated from eight. One isolate was obtained from a seropositive goose by both bioassays in mice, and in a cat; the cat fed infected heart excreted T. gondii oocysts. Additionally, one isolate was obtained from a pool of four seronegative (
Kim T Scribner - One of the best experts on this subject based on the ideXlab platform.
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the effects of anthropogenic alteration of nesting habitat on rates of extra pair fertilization and intraspecific brood parasitism in canada geese Branta Canadensis
Ibis, 2012Co-Authors: Jennifer A Moore, Kim T Scribner, Amy M Kamarainen, Curt Mykut, Harold H PrinceAbstract:Parentage studies have shown that alternative reproductive strategies are widespread in many avian taxa that were once thought to be monogamous. Recent anthropogenically mediated habitat change may have disrupted ecological factors, such as breeding density, which have given rise to inter- and intraspecific variation in the frequency of extra-pair fertilization (EPF) and intraspecific brood parasitism (IBP). We used genetic analyses to quantify the incidence of alternative reproductive strategies exhibited within clutches of Canada Geese Branta Canadensis maxima nesting in high- and low-density situations in and around urban areas in southern Michigan, USA. We tested the hypothesis that high nesting density would increase the frequency of EPF and IBP. There were no significant differences in rates of EPF and IBP clutches (14 and 26% of clutches, respectively) from nests in high-density (21.7% EPF, 21.7% IBP) vs. low-density (5.3% EPF, 31.6% IBP) areas, although high-density sites had a fourfold higher rate of EPF. Rates of EPF and IBP in high-density urban areas in Michigan were comparable to rates observed in other species nesting under different ecological conditions. Levels of relatedness between host and parasitic females were higher than expected by chance, suggesting that related females are more tolerant of one another and that host females could gain inclusive fitness benefits from rearing parasitic offspring. Our study highlights the importance of understanding the different costs and benefits associated with alternative behavioural repertoires that may vary as habitats and associated selection pressures are increasingly modified by human activities.
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phylogeography of canada geese Branta Canadensis in western north america
The Auk, 2003Co-Authors: Kim T Scribner, Sandra L Talbot, John M Pearce, Barbara J Pierson, Karen S Bollinger, Dirk V DerksenAbstract:Abstract Using molecular genetic markers that differ in mode of inheritance and rate of evolution, we examined levels and partitioning of genetic variation for seven nominal subspecies (11 breeding populations) of Canada Geese (Branta Canadensis) in western North America. Gene trees constructed from mtDNA control region sequence data show that subspecies of Canada Geese do not have distinct mtDNA. Large and small-bodied forms of Canada Geese were highly diverged (0.077 average sequence divergence) and represent monophyletic groups. A majority (65%) of 20 haplotypes resolved were observed in single breeding locales. However, within both large and small-bodied forms certain haplotypes occurred across multiple subspecies. Population trees for both nuclear (microsatellites) and mitochondrial markers were generally concordant and provide resolution of population and subspecific relationships indicating incomplete lineage sorting. All populations and subspecies were genetically diverged, but to varying degrees....
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Phylogeography of Canada Geese (Branta Canadensis) in Western North America
The Auk, 2003Co-Authors: Kim T Scribner, Sandra L Talbot, John M Pearce, Barbara J Pierson, Karen S Bollinger, Dirk V DerksenAbstract:Abstract Using molecular genetic markers that differ in mode of inheritance and rate of evolution, we examined levels and partitioning of genetic variation for seven nominal subspecies (11 breeding populations) of Canada Geese (Branta Canadensis) in western North America. Gene trees constructed from mtDNA control region sequence data show that subspecies of Canada Geese do not have distinct mtDNA. Large and small-bodied forms of Canada Geese were highly diverged (0.077 average sequence divergence) and represent monophyletic groups. A majority (65%) of 20 haplotypes resolved were observed in single breeding locales. However, within both large and small-bodied forms certain haplotypes occurred across multiple subspecies. Population trees for both nuclear (microsatellites) and mitochondrial markers were generally concordant and provide resolution of population and subspecific relationships indicating incomplete lineage sorting. All populations and subspecies were genetically diverged, but to varying degrees. Analyses of molecular variance, nested-clade and coalescencebased analyses of mtDNA suggest that both historical (past fragmentation) and contemporary forces have been important in shaping current spatial genetic distributions. Gene flow appears to be ongoing though at different rates, even among currently recognized subspecies. The efficacy of current subspecific taxonomy is discussed in light of hypothesized historical vicariance and current demographic trends of management and conservation concern.
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Molecular status of the dusky Canada goose (Branta Canadensis occidentalis): A genetic assessment of a translocation effort
Conservation Genetics, 2003Co-Authors: Sandra L Talbot, John M Pearce, Barbara J Pierson, Dirk V Derksen, Kim T ScribnerAbstract:Until recently, the dusky Canada goose (Branta Canadensis occidentalis) was managedas one breeding population from the CopperRiver Delta (CRD), Alaska. Population numberson the CRD have declined precipitously over thelast three decades, due in part to changes inhabitat. In 1981, a pair of Canada geese,presumably B.c. occidentalis, wasreported nesting on Middleton Island (MID), inthe Gulf of Alaska. Numbers of Canada geese onthe island increased in the decade subsequentto a translocation of geese from CRD to MID,but it is unclear whether the increase isattributable to the translocation effort. Weused genetic data derived from three classes ofgenetic markers to clarify relationships ofCanada geese breeding in south-coastal Alaska. Geese were sampled from 5 populations: CRD,MID, Anchorage (ANC), Admiralty Island (ADM) insoutheastern Alaska, and Green Island (GRN) inPrince William Sound (PWS). Mitochondrial DNAanalyses demonstrate Canada geese from MID arenearly monomorphic for a unique haplotype fixedon GRN but not found in CRD or any otherbreeding population. Furthermore, nuclearmarkers consistently cluster MID with GRN tothe exclusion of CRD. We suggest the currentpopulation on MID is not derived from birdstranslocated from CRD, but rather that MID wasmost likely colonised by birds inhabiting otherisland habitats within the PWS. Furthermore,since geese from the CRD share mtDNA haplotypeswith geese from other breeding locales, theyapparently share recent common ancestry and/orgene flow with populations representing othersubspecies. Our genetic data raise questionsabout the validity of current management unitsof Canada geese.
Shiv K. Verma - One of the best experts on this subject based on the ideXlab platform.
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Toxoplasmosis in geese and detection of two new atypical Toxoplasma gondii strains from naturally infected Canada geese (Branta Canadensis)
Parasitology Research, 2016Co-Authors: Shiv K. Verma, Rafael Calero-bernal, Camila K. Cerqueira-cézar, Oliver C.h. Kwok, Mike Dudley, Tiantian Jiang, Dolores Hill, Jitender P. DubeyAbstract:Wild birds are important in the epidemiology of toxoplasmosis because they can serve as reservoir hosts, and vectors of zoonotic pathogens including Toxoplasma gondii . Canada goose ( Branta Canadensis ) is the most widespread geese in North America. Little is known concerning T. gondii infection in both migratory, and local resident populations of Canada geese. Here, we evaluated the seroprevalence, isolation, and genetic characterization of viable T. gondii isolates from a migratory population of Canada geese. Antibodies against T. gondii were detected in 12 of 169 Canada geese using the modified agglutination test (MAT, cutoff 1:25). The hearts of 12 seropositive geese were bioassayed in mice for isolation of T. gondii . Viable parasites were isolated from eight. One isolate was obtained from a seropositive goose by both bioassays in mice, and in a cat; the cat fed infected heart excreted T. gondii oocysts. Additionally, one isolate was obtained from a pool of four seronegative ( < 1:25) geese by bioassay in a cat. The T. gondii isolates were further propagated in cell culture, and DNA extracted from cell culture-derived tachyzoites were characterized using 10 polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) genetic markers (SAG1, 5′ and 3′SAG2, alt.SAG2, SAG3, BTUB, GRA6, c22-8, c29-2, L358, PK1, and Apico). The results revealed five different genotypes. ToxoDB PCR-RFLP genotype #1 (type II) in one isolate, genotype #2 (type III) in four isolates, genotype #4 in two isolates, and two new genotypes (ToxoDB PCR-RFLP genotype #266 in one isolate and #267 in one isolate) were identified. These results indicate genetic diversity of T. gondii strains in the Canada geese, and this migratory bird might provide a mechanism of T. gondii transmission at great distances from where an infection was acquired.
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Toxoplasmosis in geese and detection of two new atypical Toxoplasma gondii strains from naturally infected Canada geese (Branta Canadensis).
Parasitology research, 2016Co-Authors: Shiv K. Verma, Rafael Calero-bernal, Camila K. Cerqueira-cézar, Oliver C.h. Kwok, Mike Dudley, Tiantian Jiang, Dolores E. Hill, Jitender P. DubeyAbstract:Wild birds are important in the epidemiology of toxoplasmosis because they can serve as reservoir hosts, and vectors of zoonotic pathogens including Toxoplasma gondii. Canada goose (Branta Canadensis) is the most widespread geese in North America. Little is known concerning T. gondii infection in both migratory, and local resident populations of Canada geese. Here, we evaluated the seroprevalence, isolation, and genetic characterization of viable T. gondii isolates from a migratory population of Canada geese. Antibodies against T. gondii were detected in 12 of 169 Canada geese using the modified agglutination test (MAT, cutoff 1:25). The hearts of 12 seropositive geese were bioassayed in mice for isolation of T. gondii. Viable parasites were isolated from eight. One isolate was obtained from a seropositive goose by both bioassays in mice, and in a cat; the cat fed infected heart excreted T. gondii oocysts. Additionally, one isolate was obtained from a pool of four seronegative (
Holly J Goodale - One of the best experts on this subject based on the ideXlab platform.
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infectivity of cryptosporidium parvum oocysts is retained upon intestinal passage through a migratory water fowl species canada goose Branta Canadensis
Tropical Medicine & International Health, 2007Co-Authors: Thaddeus K Graczyk, James M Trout, Ronald Fayer, Michael R Cranfield, Holly J GoodaleAbstract:Summary Five Cryptosporidium-free Canada geese (Branta Canadensis) were individually orally dosed with 3–5 × 106Cryptosporidium parvum oocysts infectious to neonatal BALB/c mice. After intestinal passage, inoculum-derived oocysts extracted from goose faeces established severe infection in 14 neonatal BALB/c mice (inoculum dose 2.5 × 105/mouse). The inoculum-derived oocysts were detected in goose faeces up to 9 days post-inoculation (PI); the number of intact oocysts and oocyst shells shed during the first 3 days PI was significantly higher than for the remaining 6 days PI (P<0.01). Based on acid-fast stained air-dried direct wet smears, 62% of the oocysts in goose faeces were intact (oocyst shells constituted 38%) and conformed to morphological features of viable and infectious inoculum oocysts. The fluorescence scores of the inoculated oocysts, obtained by use of the MERIFLUOR test, were identical to those obtained for the faeces-recovered oocysts (majority 3 + to 4 +). The dynamics of oocyst shedding showed that overall, the birds released a significantly higher number of intact oocysts than oocyst shells (P<0.01) Retention of the viability and infectivity of C. parvum oocysts following intestinal passage through a migratory water-fowl species has serious epidemiological implications. Water-fowl can serve as mechanical vectors for the water-borne oocysts and can contaminate surface waters with C. parvum. As the concentration of Cryptosporidium oocysts in source waters is attributable to water-shed management practices, water-shed protection programme officials should consider water-fowl as a potential factor enhancing contamination of the source water with Cryptosporidium.
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Infectivity of Cryptosporidium parvum oocysts is retained upon intestinal passage through a migratory water‐fowl species (Canada goose, Branta Canadensis)
Tropical medicine & international health : TM & IH, 2007Co-Authors: Thaddeus K Graczyk, James M Trout, Ronald Fayer, Michael R Cranfield, Holly J GoodaleAbstract:Summary Five Cryptosporidium-free Canada geese (Branta Canadensis) were individually orally dosed with 3–5 × 106Cryptosporidium parvum oocysts infectious to neonatal BALB/c mice. After intestinal passage, inoculum-derived oocysts extracted from goose faeces established severe infection in 14 neonatal BALB/c mice (inoculum dose 2.5 × 105/mouse). The inoculum-derived oocysts were detected in goose faeces up to 9 days post-inoculation (PI); the number of intact oocysts and oocyst shells shed during the first 3 days PI was significantly higher than for the remaining 6 days PI (P
Richard Schodde - One of the best experts on this subject based on the ideXlab platform.
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case 3682 the work the white cheeked geese Branta Canadensis b maxima b lawrensis b hutchinsii b leucopareia and b minima taxonomy ecophysiographic relationships biogeography and evolutionary considerations volume 1 eastern taxa volume 2 western taxa
The Bulletin of zoological nomenclature, 2015Co-Authors: Richard C Banks, Mary Lecroy, Richard SchoddeAbstract:The purpose of this application under Articles 78.1 and 81.1 of the Code is to suppress for nomenclatural purposes the two-volume work ‘The White-cheeked geese: Branta Canadensis, B. maxima, B. ‘lawrensis’, B. hutchinsii, B. leucopareia, and B. minima. Taxonomy, ecophysiographic relationships, biogeography, and evolutionary considerations,’ by Harold C. Hanson. Reasons for suppression are the work's many confounded new taxon designations, inappropriately chosen types, inadequately diagnosed new taxa, variable and confused authorships, and a flawed neotype designation. Together they serve as evidence of general nomenclatural dysfunction. If not suppressed, Hanson's work will become a source of destabilisation the nomenclature of the Branta Canadensis complex.
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Case 3682 The work ‘The White-cheeked Geese: Branta Canadensis, B. maxima, B. ‘lawrensis’, B. hutchinsii, B. leucopareia, and B. minima. Taxonomy, ecophysiographic relationships, biogeography, and evolutionary considerations, Volume 1, Eastern taxa;
The Bulletin of Zoological Nomenclature, 2015Co-Authors: Richard C Banks, Mary Lecroy, Richard SchoddeAbstract:The purpose of this application under Articles 78.1 and 81.1 of the Code is to suppress for nomenclatural purposes the two-volume work ‘The White-cheeked geese: Branta Canadensis, B. maxima, B. ‘lawrensis’, B. hutchinsii, B. leucopareia, and B. minima. Taxonomy, ecophysiographic relationships, biogeography, and evolutionary considerations,’ by Harold C. Hanson. Reasons for suppression are the work's many confounded new taxon designations, inappropriately chosen types, inadequately diagnosed new taxa, variable and confused authorships, and a flawed neotype designation. Together they serve as evidence of general nomenclatural dysfunction. If not suppressed, Hanson's work will become a source of destabilisation the nomenclature of the Branta Canadensis complex.