1
|
Pollo F, Salinas Z, Baraquet M, Otero MA, Grenat PR, Salas N, Martino AL, Sinsch U. Hemoparasites Do Not Affect Life-History Traits and Cellular Immune Response in Treefrog Hosts Boana cordobae. Animals (Basel) 2023; 13:3566. [PMID: 38003183 PMCID: PMC10668743 DOI: 10.3390/ani13223566] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2023] [Revised: 11/15/2023] [Accepted: 11/17/2023] [Indexed: 11/26/2023] Open
Abstract
We provide the first evidence for hemoparasites in the endemic Cordoba treefrog Boana cordobae. We collected 37 adult frogs at 1200 m a.s.l. in the Comechingones Mountains in the Córdoba province (Argentina). Each individual was sexed, then snout-vent length and body mass were recorded, a toe was collected for skeletochronological age determination, and a slide with a blood smear was prepared for hemoparasite screening, before releasing the frogs in situ. A total of 81% (n = 30) of the frogs were infected by hemogregarines and trypanosomes with a high intensity of infections. Dactylosoma was found for the first time in Argentina. Hemoparasites had no significant effect on the leukocyte profile, which we assessed from the May-Grünwald-Giemsa-stained blood smears. The neutrophils/lymphocytes ratio, indicative of stress, was insignificantly higher (0.06) in parasitized frogs than in parasite-free individuals (0.04). Infected frogs were larger than the controls, but this effect vanished when correcting size data for age. Young frogs (first-breeders) dominated the age distribution of parasite-free individuals, suggesting that infection of frogs takes usually place after sexual maturation. Vectors transmitting hemoparasites to B. cordobae remain to be identified. We demonstrate that moderate to high intensities of hemoparasites do not significantly affect the cellular immune response of B. cordobae, or any of the life-history traits studied, nor did they show any external sign of disease.
Collapse
Affiliation(s)
- Favio Pollo
- Ecología, Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional N° 36–km 601, Río Cuarto X5804BYA, Argentina; (F.P.); (Z.S.); (M.B.); (M.A.O.); (P.R.G.); (N.S.); (A.L.M.)
- Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente, Consejo Nacional de Investigaciones Científicas y Técnicas, Rosario S2000EZ, Argentina
| | - Zulma Salinas
- Ecología, Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional N° 36–km 601, Río Cuarto X5804BYA, Argentina; (F.P.); (Z.S.); (M.B.); (M.A.O.); (P.R.G.); (N.S.); (A.L.M.)
- Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente, Consejo Nacional de Investigaciones Científicas y Técnicas, Rosario S2000EZ, Argentina
| | - Mariana Baraquet
- Ecología, Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional N° 36–km 601, Río Cuarto X5804BYA, Argentina; (F.P.); (Z.S.); (M.B.); (M.A.O.); (P.R.G.); (N.S.); (A.L.M.)
- Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente, Consejo Nacional de Investigaciones Científicas y Técnicas, Rosario S2000EZ, Argentina
| | - Manuel A. Otero
- Ecología, Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional N° 36–km 601, Río Cuarto X5804BYA, Argentina; (F.P.); (Z.S.); (M.B.); (M.A.O.); (P.R.G.); (N.S.); (A.L.M.)
- Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente, Consejo Nacional de Investigaciones Científicas y Técnicas, Rosario S2000EZ, Argentina
| | - Pablo R. Grenat
- Ecología, Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional N° 36–km 601, Río Cuarto X5804BYA, Argentina; (F.P.); (Z.S.); (M.B.); (M.A.O.); (P.R.G.); (N.S.); (A.L.M.)
- Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente, Consejo Nacional de Investigaciones Científicas y Técnicas, Rosario S2000EZ, Argentina
| | - Nancy Salas
- Ecología, Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional N° 36–km 601, Río Cuarto X5804BYA, Argentina; (F.P.); (Z.S.); (M.B.); (M.A.O.); (P.R.G.); (N.S.); (A.L.M.)
- Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente, Consejo Nacional de Investigaciones Científicas y Técnicas, Rosario S2000EZ, Argentina
| | - Adolfo L. Martino
- Ecología, Departamento de Ciencias Naturales, Facultad de Ciencias Exactas, Físico-Químicas y Naturales, Universidad Nacional de Río Cuarto, Ruta Nacional N° 36–km 601, Río Cuarto X5804BYA, Argentina; (F.P.); (Z.S.); (M.B.); (M.A.O.); (P.R.G.); (N.S.); (A.L.M.)
- Instituto de Ciencias de la Tierra, Biodiversidad y Ambiente, Consejo Nacional de Investigaciones Científicas y Técnicas, Rosario S2000EZ, Argentina
| | - Ulrich Sinsch
- Department of Biology, Zoology Group, University of Koblenz, 56070 Koblenz, Germany
| |
Collapse
|
2
|
Ranavirus genotypes in the Netherlands and their potential association with virulence in water frogs (Pelophylax spp.). Emerg Microbes Infect 2018; 7:56. [PMID: 29615625 PMCID: PMC5882854 DOI: 10.1038/s41426-018-0058-5] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 12/04/2017] [Accepted: 02/25/2018] [Indexed: 12/15/2022]
Abstract
Ranaviruses are pathogenic viruses for poikilothermic vertebrates worldwide. The identification of a common midwife toad virus (CMTV) associated with massive die-offs in water frogs (Pelophylax spp.) in the Netherlands has increased awareness for emerging viruses in amphibians in the country. Complete genome sequencing of 13 ranavirus isolates collected from ten different sites in the period 2011–2016 revealed three CMTV groups present in distinct geographical areas in the Netherlands. Phylogenetic analysis showed that emerging viruses from the northern part of the Netherlands belonged to CMTV-NL group I. Group II and III viruses were derived from the animals located in the center-east and south of the country, and shared a more recent common ancestor to CMTV-amphibian associated ranaviruses reported in China, Italy, Denmark, and Switzerland. Field monitoring revealed differences in water frog host abundance at sites where distinct ranavirus groups occur; with ranavirus-associated deaths, host counts decreasing progressively, and few juveniles found in the north where CMTV-NL group I occurs but not in the south with CMTV-NL group III. Investigation of tandem repeats of coding genes gave no conclusive information about phylo-geographical clustering, while genetic analysis of the genomes revealed truncations in 17 genes across CMTV-NL groups II and III compared to group I. Further studies are needed to elucidate the contribution of these genes as well as environmental variables to explain the observed differences in host abundance.
Collapse
|
3
|
Rijks JM, Saucedo B, Spitzen-van der Sluijs A, Wilkie GS, van Asten AJAM, van den Broek J, Boonyarittichaikij R, Stege M, van der Sterren F, Martel A, Pasmans F, Hughes J, Gröne A, van Beurden SJ, Kik MJL. Investigation of Amphibian Mortality Events in Wildlife Reveals an On-Going Ranavirus Epidemic in the North of the Netherlands. PLoS One 2016; 11:e0157473. [PMID: 27315226 PMCID: PMC4912076 DOI: 10.1371/journal.pone.0157473] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2015] [Accepted: 05/30/2016] [Indexed: 12/15/2022] Open
Abstract
In the four years following the first detection of ranavirus (genus Ranavirus, family Iridoviridae) infection in Dutch wildlife in 2010, amphibian mortality events were investigated nationwide to detect, characterize and map ranaviruses in amphibians over time, and to establish the affected host species and the clinico-pathological presentation of the disease in these hosts. The ultimate goal was to obtain more insight into ranavirus disease emergence and ecological risk. In total 155 dead amphibians from 52 sites were submitted between 2011 and 2014, and examined using histopathology, immunohistochemistry, virus isolation and molecular genetic characterization. Ranavirus-associated amphibian mortality events occurred at 18 sites (35%), initially only in proximity of the 2010 index site. Specimens belonging to approximately half of the native amphibian species were infected, including the threatened Pelobates fuscus (spadefoot toad). Clustered massive outbreaks involving dead adult specimens and ranavirus genomic identity indicated that one common midwife toad virus (CMTV)-like ranavirus strain is emerging in provinces in the north of the Netherlands. Modelling based on the spatiotemporal pattern of spread showed a high probability that this emerging virus will continue to be detected at new sites (the discrete reproductive power of this outbreak is 0.35). Phylogenetically distinct CMTV-like ranaviruses were found in the south of the Netherlands more recently. In addition to showing that CMTV-like ranaviruses threaten wild amphibian populations not only in Spain but also in the Netherlands, the current spread and risk of establishment reiterate that understanding the underlying causes of CMTV-like ranavirus emergence requires international attention.
Collapse
Affiliation(s)
- Jolianne M. Rijks
- Dutch Wildlife Health Centre, Utrecht University, Utrecht, The Netherlands
- * E-mail:
| | - Bernardo Saucedo
- Dutch Wildlife Health Centre, Utrecht University, Utrecht, The Netherlands
- Department of Pathobiology, Utrecht University, Utrecht, The Netherlands
| | | | - Gavin S. Wilkie
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Alphons J. A. M. van Asten
- Dutch Wildlife Health Centre, Utrecht University, Utrecht, The Netherlands
- Department of Pathobiology, Utrecht University, Utrecht, The Netherlands
| | - Jan van den Broek
- Department of Farm Animal Health, Utrecht University, Utrecht, The Netherlands
| | | | - Marisca Stege
- Department of Pathobiology, Utrecht University, Utrecht, The Netherlands
| | | | - An Martel
- Department of Pathology, Bacteriology and Avian Diseases, Ghent University, Merelbeke, Belgium
| | - Frank Pasmans
- Department of Pathology, Bacteriology and Avian Diseases, Ghent University, Merelbeke, Belgium
| | - Joseph Hughes
- MRC-University of Glasgow Centre for Virus Research, Glasgow, United Kingdom
| | - Andrea Gröne
- Dutch Wildlife Health Centre, Utrecht University, Utrecht, The Netherlands
- Department of Pathobiology, Utrecht University, Utrecht, The Netherlands
| | | | - Marja J. L. Kik
- Dutch Wildlife Health Centre, Utrecht University, Utrecht, The Netherlands
- Department of Pathobiology, Utrecht University, Utrecht, The Netherlands
| |
Collapse
|