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Edward C Netherlands - One of the best experts on this subject based on the ideXlab platform.
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ultrastructural comparison of hepatozoon ixoxo and hepatozoon theileri adeleorina hepatozoidae parasitising south african anurans
Journal of Eukaryotic Microbiology, 2017Co-Authors: Roxanne Conradie, Edward C Netherlands, Courtney A Cook, Louis H Du Preez, Anine JordaanAbstract:To date, only two haemogregarine parasite species have been described from South African anurans: Hepatozoon ixoxo, infecting toads of the genus Sclerophrys (syn. Amietophrynus); and Hepatozoon theileri, parasitising the common river frog, Amietia quecketti. Both species have been characterised using limited morphology, and molecular data from PCR amplified fragments of the 18S rRNA gene. However, no ultrastructural work has been performed thus far. The aim of this study was to add descriptive information on the two species by studying their ultrastructural morphology. Mature gamont stages, common in the peripheral blood of infected frogs, were examined by transmission electron microscopy. Results indicate that H. ixoxo and H. theileri share typical apicomplexan characteristics, but differ markedly in their external cellular structure. Hepatozoon ixoxo is an encapsulated parasite presenting a prominent cap at the truncate pole, and shows no visible modifications to the host cell membrane. In comparison, H. theileri does not present a capsule or cap, and produces marked morphological changes to its host cell. Scanning electron microscopy was performed to further examine the cytopathological effects of H. theileri, and results revealed small, knob-like protrusions on the erythrocyte surface, as well as notable distortion of the overall shape of the host cell.
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hepatozoon species adeleorina hepatozoidae of african bufonids with morphological description and molecular diagnosis of hepatozoon ixoxo sp nov parasitising three Amietophrynus species anura bufonidae
Parasites & Vectors, 2014Co-Authors: Edward C Netherlands, Courtney A Cook, Nico J SmitAbstract:Haemogregarines comprise a large group of apicomplexan blood parasites. In 1996 all anuran haemogregarines still in the genus Haemogregarina Danilewsky, 1885 were reassigned to the genus Hepatozoon Miller, 1908. Most (11/15, 73%) African anuran Hepatozoon species have been recorded from the family Bufonidae, however, all these are recorded from only two host species, Amietophrynus mauritanicus (Schlegel, 1841) and Amietophrynus regularis (Reuss, 1833) from Northern and central Africa. To the authors’ knowledge the only description of an anuran haemogregarine from South Africa is Hepatozoon theileri (Laveran, 1905), parasitising Amietia quecketti (Boulenger, 1895). Thin blood smears for morphometrics and whole blood for molecular work, were collected from 32 Amietophrynus garmani (Meek, 1897), 12 Amietophrynus gutturalis (Power, 1927), and nine Amietophrynus maculatus (Hallowell, 1854), in Ndumo Game Reserve and Kwa Nyamazane Conservancy, KwaZulu-Natal, South Africa. Smears were Giemsa-stained, screened for haemogregarines, parasite stages measured, compared to each other and to other described African bufonid haemogregarines. Parasite 18S rDNA was amplified using two apicomplexan-specific primer sets, HepF300/HepR900 and 4558/2733. Resulting sequences of the haemogregarine isolates from the three Amietophrynus species were compared with each other and to comparative haemogregarine sequences selected from GenBank. Morphological characteristics of parasite stages, in particular characteristically capped mature gamont stages, and molecular findings, supported all three haemogregarine isolates from all three Amietophrynus species to be the same, a species of Hepatozoon, and furthermore different morphologically from other previously recorded bufonid Hepatozoon species. The haemogregarine fell within a clade comprising other anuran Hepatozoon species and furthermore, within a monophyletic sub-clade along with H. theileri and are described as Hepatozoon ixoxo sp. nov. This is the first morphological and molecular account of Hepatozoon species within the family Bufonidae from South Africa, a study hoped to encourage the redescription and molecular analysis of those Hepatozoon species described in the past from Amietophrynus species, as well as to promote the use of both morphological and molecular characteristics in Hepatozoon species descriptions. This will aid in comprehensive Hepatozoon descriptions, which along with the use of phylogenetic analysis will give a better indication of these parasites possible vectors and life cycle dynamics.
Nico J Smit - One of the best experts on this subject based on the ideXlab platform.
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nov. parasitising three Amietophrynus species
2016Co-Authors: Edward C Netherl, Courtney A Cook, Nico J SmitAbstract:DOI 10.1186/s13071-014-0552-0Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africastages, and molecular findings, supported all three haemogregarine isolates from all three Amietophrynus species to be the same, a species of Hepatozoon, and furthermore different morphologically from other previously recorded bufonid Hepatozoon species. The haemogregarine fell within a clade comprising other anuran Hepatozoon species and furthermore, within a monophyletic sub-clade along with H. theileri and are described as Hepatozoon ixoxo sp. nov. (Continued on next page
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hepatozoon species adeleorina hepatozoidae of african bufonids with morphological description and molecular diagnosis of hepatozoon ixoxo sp nov parasitising three Amietophrynus species anura bufonidae
Parasites & Vectors, 2014Co-Authors: Edward C Netherlands, Courtney A Cook, Nico J SmitAbstract:Haemogregarines comprise a large group of apicomplexan blood parasites. In 1996 all anuran haemogregarines still in the genus Haemogregarina Danilewsky, 1885 were reassigned to the genus Hepatozoon Miller, 1908. Most (11/15, 73%) African anuran Hepatozoon species have been recorded from the family Bufonidae, however, all these are recorded from only two host species, Amietophrynus mauritanicus (Schlegel, 1841) and Amietophrynus regularis (Reuss, 1833) from Northern and central Africa. To the authors’ knowledge the only description of an anuran haemogregarine from South Africa is Hepatozoon theileri (Laveran, 1905), parasitising Amietia quecketti (Boulenger, 1895). Thin blood smears for morphometrics and whole blood for molecular work, were collected from 32 Amietophrynus garmani (Meek, 1897), 12 Amietophrynus gutturalis (Power, 1927), and nine Amietophrynus maculatus (Hallowell, 1854), in Ndumo Game Reserve and Kwa Nyamazane Conservancy, KwaZulu-Natal, South Africa. Smears were Giemsa-stained, screened for haemogregarines, parasite stages measured, compared to each other and to other described African bufonid haemogregarines. Parasite 18S rDNA was amplified using two apicomplexan-specific primer sets, HepF300/HepR900 and 4558/2733. Resulting sequences of the haemogregarine isolates from the three Amietophrynus species were compared with each other and to comparative haemogregarine sequences selected from GenBank. Morphological characteristics of parasite stages, in particular characteristically capped mature gamont stages, and molecular findings, supported all three haemogregarine isolates from all three Amietophrynus species to be the same, a species of Hepatozoon, and furthermore different morphologically from other previously recorded bufonid Hepatozoon species. The haemogregarine fell within a clade comprising other anuran Hepatozoon species and furthermore, within a monophyletic sub-clade along with H. theileri and are described as Hepatozoon ixoxo sp. nov. This is the first morphological and molecular account of Hepatozoon species within the family Bufonidae from South Africa, a study hoped to encourage the redescription and molecular analysis of those Hepatozoon species described in the past from Amietophrynus species, as well as to promote the use of both morphological and molecular characteristics in Hepatozoon species descriptions. This will aid in comprehensive Hepatozoon descriptions, which along with the use of phylogenetic analysis will give a better indication of these parasites possible vectors and life cycle dynamics.
Theerakamol Pengsakul - One of the best experts on this subject based on the ideXlab platform.
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helminth parasites of the subdesert toad Amietophrynus bufo xeros anura bufonidae
International Journal of Research, 2015Co-Authors: Yassir Sulieman, Azzam Afifi, Higazi Mohammed Ahmed Abdallah Awad, Theerakamol PengsakulAbstract:Sixty-nine subdesert toads, Amietophrynus (Bufo) xeros, were collected in Shendi, Sudan, from August to November 2014, and examined for the first time for the presence of internal helminth parasites. Sixty-seven (97.1%) of the toads were found infected with one or more helminth species including, four Nematoda: Aplectana macintoshii, Rhabdias bufonis, Strongyloides prokopici, and Oswaldocruzia sp.; one Trematoda: Mesocoelium sp.; one Cestoda: Lanfrediella sp. A higher prevalence and intensity of infection was found in male toads compared with females, and old toads were found to harbor a higher prevalence and intensity of infection when compared to younger ones. However, neither of these differences was statistically significant. In addition, there were no significant correlations found between the gender of the toads examined and either the prevalence or intensity of infection of any of the helminth species. Likewise, the prevalence and intensity of infection of the helminth species were not significantly correlated with the snout-vent length of the toads.
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non hemoparasitic protozoa of the subdesert toad Amietophrynus bufo xeros anura bufonidae
International Journal of Fauna and Biological Studies, 2015Co-Authors: Yassir Sulieman, Theerakamol PengsakulAbstract:Eighty subdesert toads, Amietophrynus (Bufo) xeros, were collected in Shendi, Sudan, between August and December 2014 and examined for the presence of non-hemoparasitic protozoa. Fifty-four (67.5%) of the toads were found to be infected with one or more protozoa including, Nyctotherus sp., Balantidium sp.Opalina sp. and Protoopalina sp. A higher prevalence of infection was found in female toads, while a higher intensity of infection was found in males. In addition, older toads harbored a higher prevalence and intensity of infection. No significant correlations were found between the gender of the toads examined and either the prevalence or intensity of infection of the protozoan species. Likewise, the prevalence and intensity of infection by protozoan species were not significantly correlated with the snout-vent length of the toads.
Barej Michael - One of the best experts on this subject based on the ideXlab platform.
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Figure 5 from: Onadeko A, Roedel M, Liedtke H, Barej M (2014) The rediscovery of Perret's toad, Amietophrynus perreti (Schiøtz, 1963) after more than 40 years, with comments on the species' phylogenetic placement and conservation status. Zoosystematics and Evolution 90(2): 113-119. https://doi.org/10.3897/zse.90.8234
2014Co-Authors: Onadeko, Abiodun B., Roedel Mark-oliver, Liedtke H. Christoph, Barej MichaelAbstract:Figure 5 - Systematic placement (Bayesian phylogenetic inference based on a mitochondrial fragment of the 16S rRNA gene) of Amietophrynus perreti within the genus Amietophrynus. Bayesian PP values are as follows: asterisks ('*') point to maximum support (1.00), full circles ('●') point to PP 0.95–0.99; empty circle ('○') point to PP 0.90–0.94; PP values below 0.90 not shown
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Figure 2 from: Onadeko A, Roedel M, Liedtke H, Barej M (2014) The rediscovery of Perret's toad, Amietophrynus perreti (Schiøtz, 1963) after more than 40 years, with comments on the species' phylogenetic placement and conservation status. Zoosystematics and Evolution 90(2): 113-119. https://doi.org/10.3897/zse.90.8234
2014Co-Authors: Onadeko, Abiodun B., Roedel Mark-oliver, Liedtke H. Christoph, Barej MichaelAbstract:Figure 2 - The Idanre Hills inselbergs in south-western Nigeria (a-f), the type locality and only known habitat of Amietophrynus perreti. Survey site A was only about 50 m from the last house in a; b: figures a overflown part of rock at site B; c: some Amietophrynus perreti were observed close to the waste dumping site (left at the rock base), probably feeding on flies or other insects; d: a road leading to Site C, the cocoa farm being further in the background adjacent to the large rock; e: part of site C
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Figure 3 from: Onadeko A, Roedel M, Liedtke H, Barej M (2014) The rediscovery of Perret's toad, Amietophrynus perreti (Schiøtz, 1963) after more than 40 years, with comments on the species' phylogenetic placement and conservation status. Zoosystematics and Evolution 90(2): 113-119. https://doi.org/10.3897/zse.90.8234
2014Co-Authors: Onadeko, Abiodun B., Roedel Mark-oliver, Liedtke H. Christoph, Barej MichaelAbstract:Figure 3 - Sites around Idanre Hills surveyed for Amietophrynus perreti; green circles: toads recorded, red crosses: toads not found
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Figure 4 from: Onadeko A, Roedel M, Liedtke H, Barej M (2014) The rediscovery of Perret's toad, Amietophrynus perreti (Schiøtz, 1963) after more than 40 years, with comments on the species' phylogenetic placement and conservation status. Zoosystematics and Evolution 90(2): 113-119. https://doi.org/10.3897/zse.90.8234
2014Co-Authors: Onadeko, Abiodun B., Roedel Mark-oliver, Liedtke H. Christoph, Barej MichaelAbstract:Figure 4 - A specimen of the rediscovered Amietophrynus perreti from the type locality, the Idanre Hills, south-western Nigeria
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Figure 1 from: Onadeko A, Roedel M, Liedtke H, Barej M (2014) The rediscovery of Perret's toad, Amietophrynus perreti (Schiøtz, 1963) after more than 40 years, with comments on the species' phylogenetic placement and conservation status. Zoosystematics and Evolution 90(2): 113-119. https://doi.org/10.3897/zse.90.8234
2014Co-Authors: Onadeko, Abiodun B., Roedel Mark-oliver, Liedtke H. Christoph, Barej MichaelAbstract:Figure 1 - Habitat (right) of Amietophrynus perreti tadpoles (left) at the type locality, the Idanre Hills in Nigeria (photos: courtesy of A. Schiøtz)
Courtney A Cook - One of the best experts on this subject based on the ideXlab platform.
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ultrastructural comparison of hepatozoon ixoxo and hepatozoon theileri adeleorina hepatozoidae parasitising south african anurans
Journal of Eukaryotic Microbiology, 2017Co-Authors: Roxanne Conradie, Edward C Netherlands, Courtney A Cook, Louis H Du Preez, Anine JordaanAbstract:To date, only two haemogregarine parasite species have been described from South African anurans: Hepatozoon ixoxo, infecting toads of the genus Sclerophrys (syn. Amietophrynus); and Hepatozoon theileri, parasitising the common river frog, Amietia quecketti. Both species have been characterised using limited morphology, and molecular data from PCR amplified fragments of the 18S rRNA gene. However, no ultrastructural work has been performed thus far. The aim of this study was to add descriptive information on the two species by studying their ultrastructural morphology. Mature gamont stages, common in the peripheral blood of infected frogs, were examined by transmission electron microscopy. Results indicate that H. ixoxo and H. theileri share typical apicomplexan characteristics, but differ markedly in their external cellular structure. Hepatozoon ixoxo is an encapsulated parasite presenting a prominent cap at the truncate pole, and shows no visible modifications to the host cell membrane. In comparison, H. theileri does not present a capsule or cap, and produces marked morphological changes to its host cell. Scanning electron microscopy was performed to further examine the cytopathological effects of H. theileri, and results revealed small, knob-like protrusions on the erythrocyte surface, as well as notable distortion of the overall shape of the host cell.
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nov. parasitising three Amietophrynus species
2016Co-Authors: Edward C Netherl, Courtney A Cook, Nico J SmitAbstract:DOI 10.1186/s13071-014-0552-0Unit for Environmental Sciences and Management, North-West University, Potchefstroom, South Africastages, and molecular findings, supported all three haemogregarine isolates from all three Amietophrynus species to be the same, a species of Hepatozoon, and furthermore different morphologically from other previously recorded bufonid Hepatozoon species. The haemogregarine fell within a clade comprising other anuran Hepatozoon species and furthermore, within a monophyletic sub-clade along with H. theileri and are described as Hepatozoon ixoxo sp. nov. (Continued on next page
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hepatozoon species adeleorina hepatozoidae of african bufonids with morphological description and molecular diagnosis of hepatozoon ixoxo sp nov parasitising three Amietophrynus species anura bufonidae
Parasites & Vectors, 2014Co-Authors: Edward C Netherlands, Courtney A Cook, Nico J SmitAbstract:Haemogregarines comprise a large group of apicomplexan blood parasites. In 1996 all anuran haemogregarines still in the genus Haemogregarina Danilewsky, 1885 were reassigned to the genus Hepatozoon Miller, 1908. Most (11/15, 73%) African anuran Hepatozoon species have been recorded from the family Bufonidae, however, all these are recorded from only two host species, Amietophrynus mauritanicus (Schlegel, 1841) and Amietophrynus regularis (Reuss, 1833) from Northern and central Africa. To the authors’ knowledge the only description of an anuran haemogregarine from South Africa is Hepatozoon theileri (Laveran, 1905), parasitising Amietia quecketti (Boulenger, 1895). Thin blood smears for morphometrics and whole blood for molecular work, were collected from 32 Amietophrynus garmani (Meek, 1897), 12 Amietophrynus gutturalis (Power, 1927), and nine Amietophrynus maculatus (Hallowell, 1854), in Ndumo Game Reserve and Kwa Nyamazane Conservancy, KwaZulu-Natal, South Africa. Smears were Giemsa-stained, screened for haemogregarines, parasite stages measured, compared to each other and to other described African bufonid haemogregarines. Parasite 18S rDNA was amplified using two apicomplexan-specific primer sets, HepF300/HepR900 and 4558/2733. Resulting sequences of the haemogregarine isolates from the three Amietophrynus species were compared with each other and to comparative haemogregarine sequences selected from GenBank. Morphological characteristics of parasite stages, in particular characteristically capped mature gamont stages, and molecular findings, supported all three haemogregarine isolates from all three Amietophrynus species to be the same, a species of Hepatozoon, and furthermore different morphologically from other previously recorded bufonid Hepatozoon species. The haemogregarine fell within a clade comprising other anuran Hepatozoon species and furthermore, within a monophyletic sub-clade along with H. theileri and are described as Hepatozoon ixoxo sp. nov. This is the first morphological and molecular account of Hepatozoon species within the family Bufonidae from South Africa, a study hoped to encourage the redescription and molecular analysis of those Hepatozoon species described in the past from Amietophrynus species, as well as to promote the use of both morphological and molecular characteristics in Hepatozoon species descriptions. This will aid in comprehensive Hepatozoon descriptions, which along with the use of phylogenetic analysis will give a better indication of these parasites possible vectors and life cycle dynamics.