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1.
Microorganisms ; 10(10)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36296199

RESUMO

Reptiles are hosts for various tick species and tick-associated organisms, many of which are zoonotic. However, little is known about the presence and diversity of tick-borne bacteria infecting reptiles and their ticks in South Africa. Amblyomma ticks (n = 253) collected from reptiles were screened for the presence of Coxiella, Anaplasma, Rickettsia, and Borrelia species by amplification, sequencing and phylogenetic analysis of the 16S rRNA, 23S rRNA, gltA, OmpA, and Flagellin genes, respectively. This study recorded the presence of reptile associated Borrelia species and Coxiella-like endosymbiont in South Africa for the first time. Furthermore, a spotted fever group Rickettsia species was observed in 7 Amblyomma marmoreum and 14 Amblyomma sylvaticum from tortoises of genera Kinixys and Chersina. Francisella-like endosymbiont was observed from 2 Amblyomma latum collected from the Mozambique spitting cobra, Naja mossambica. Coxiella burnetii and Anaplasma spp., were not detected from the current samples. Although the direct evidence that reptiles can act as reservoir hosts remains to be determined, observations from this study provide indications that reptilian ticks may play a role in the transmission of pathogenic bacteria to homothermic animals. Furthermore, the absence of Anaplasma spp., and C. burnetii does not mean that these pathogens should be completely neglected.

2.
Int J Parasitol Parasites Wildl ; 16: 163-167, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34584839

RESUMO

In South Africa, the role of reptilian ticks in the transmission of haemoparasites is lacking, in part, due to limited information on tick diversity and their associated haemoparasites. The aim of this research was to identify tick species parasitizing reptiles and to molecularly screen these ectoparasites for species of the blood apicomplexan genus Hepatozoon. Samples were collected from Ndumo Game Reserve, KwaZulu-Natal, and the Cape Columbine region, Western Cape. Reptiles collected included 2 snakes, 2 monitor lizards of a single species respectively, as well as 17 tortoises of four species. Ticks collected from these were morphologically identified as Amblyomma latum (n = 2) and Amblyomma marmoreum (n = 98), this identification was molecularly confirmed using 16S rRNA and CO1 genes. Screening for Hepatozoon was done by amplifying the 18S rRNA gene. A species of Hepatozoon, Hepatozoon fitzsimonsi, was identified from A. marmoreum ticks, with an overall prevalence of 10%. This Hepatozoon species, has been described parasitizing tortoises from southern Africa, and has been reported from ticks infesting tortoises from Kenya, East Africa. Even though ticks have been suggested to be the likely vector of this Hepatozoon species, with this supported by the findings of Hepatozoon-like developmental stages in ticks collected off of infected tortoises, a recent systematic revision placed this species in a newly erected genus Bartazoon, a genus vectorised by biting insects. The present study thus provides further support for ticks acting as the potential vectors of H. fitzsimonsi.

3.
Int J Parasitol Parasites Wildl ; 15: 143-152, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34026484

RESUMO

With over 200 species of sharks reported from South African waters, the potential of discovering new blood parasites is very high. Unfortunately, this remains a poorly explored area of research, particularly in this biogeographical region. To date, only a single trypanosome species, Trypanosoma haploblephari Yeld and Smit, 2006, has been described from elasmobranchs off the coast of South Africa infecting the catsharks Haploblepharus pictus (Müller & Henle) and Haploblepharus edwardsii (Schinz). With only a single trypanosome species described and absence of molecular information, a study was conducted to provide further morphological and molecular information on T. haploblephari, a species considered not to demonstrate any pleomorphism. Thin blood smears were prepared, and blood was collected in molecular-grade ethanol from the caudal vein of two shark species, H. pictus and Poroderma pantherinum (Müller & Henle). Trypanosomes were morphologically described and molecularly characterised based on analysis of fragments of the 18S ribosomal gene. The presence of T. haploblephari in H. pictus was confirmed using the original description based on morphology, type host and locality, which allowed for the molecular characterisation of the species. In addition, this species was found parasitising P. pantherinum, its morphology considerably different in this host species as compared to that in the species of Haploblepharus, demonstrating that T. haploblephari may show extreme pleomorphism. This paper provides both morphological and molecular data for both morphotypes of T. haploblephari, with molecular comparisons to the only two other elasmobranch species of trypanosome for which sequence data is available. To elucidate the relationship of trypanosomes from aquatic hosts in general, more efforts need to be placed on elasmobranchs, as current phylogenetic studies are predominantly focused on trypanosomes infecting freshwater fishes.

4.
Int J Parasitol ; 50(10-11): 921-929, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32687913

RESUMO

Trypanosomes are ubiquitous blood parasites of fishes and at least 16 species were originally described infecting African freshwater fishes. This number was later reduced to six and in the late 1990s it was proposed that most records of freshwater fish trypanosomes across Africa are Trypanosoma mukasai Hoare, 1932. Recently, results from a molecular analysis of fish trypanosomes from the Okavango Delta, Botswana, reported the presence of at least two genotypic groups and concluded that the identification of T. mukasai remains problematic. The aims of the present study were thus to elucidate the life cycle of a freshwater fish trypanosome from southern Africa and to do a morphological and molecular characterization of this parasite from both the fish host and leech vector. To locate trypanosome stages, leeches were removed from fishes captured in the Phongolo River, South Africa, and fish blood films and leech squashes were Giemsa-stained and screened. To determine whether trypanosome stages in fishes and leeches were of the same genotype, DNA was extracted and fragments of the 18S rDNA gene were amplified and sequenced. Trypanosomes were detected in the fish families Cichlidae, Clariidae, Mochokidae and Schilbeidae. Sequence data showed that the trypanosome from one of the leeches, identified as Batracobdelloides tricarinata (Blanchard, 1897), was highly similar to those obtained from the plain squeaker, Synodontis zambezensis, with 0.7% difference recorded between them. From morphological and molecular data presented here, it is clear that the trypanosomes from Phongolo are closely related to those of the Okavango and should be considered as a single diverse species with genetic differentiation between 0.4-2.9%, under the 3-5% differences expected to be seen between true distinct species within the rRNA. Developmental stages of the trypanosome found in the leech B. tricarinata supports its status as the vector and the molecular evidence shows the relationship between the trypanosome in the fish and leech, but also illustrates the exceptional genetic and morphological diversity of a single species of trypanosome between host species. The work presented here provides us with clear information to take further steps in resolving the taxonomy and systematics of African freshwater fish trypanosomes.


Assuntos
Peixes/parasitologia , Sanguessugas , Trypanosoma , Animais , Doenças dos Peixes/parasitologia , Água Doce , Sanguessugas/parasitologia , Filogenia , RNA Ribossômico 18S , África do Sul , Trypanosoma/classificação , Trypanosoma/crescimento & desenvolvimento
5.
Int J Parasitol Parasites Wildl ; 11: 246-260, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32195110

RESUMO

Haemogregarine (Apicomplexa: Adeleorina) blood parasites are commonly reported from anuran hosts. Dactylosomatidae (Jakowska and Nigrelli, 1955) is a group of haemogregarines comprising Dactylosoma Labbé, 1894 and Babesiosoma Jakowska and Nigrelli, 1956. Currently Dactylosoma and Babesiosoma contain five recognised species each. In the current study, a total of 643 anurans, comprising 38 species, 20 genera, and 13 families were collected from South Africa (n = 618) and Belgium (n = 25), and their blood screened for the presence of dactylosomatid parasites. Three anuran species were found infected namely, Ptychadena anchietae (Bocage, 1868) and Sclerophrys gutturalis (Power, 1927) from South Africa, and Pelophylax lessonae (Camerano, 1882) from Belgium. Based on morphological characteristics, morphometrics and molecular results a new dactylosomatid, Dactylosoma kermiti n. sp. is described form Pty. anchietae and Scl. gutturalis. The species of Dactylosoma isolated from Pel. lessonae could not, based on morphological or molecular analysis, be identified to species level. Phylogenetic analysis shows species of Dactylosoma infecting anurans as a monophyletic group separate from the other haemogregarine groups. Additionally, the mosquitoes Uranotaenia (Pseudoficalbia) mashonaensis Theobald, 1901 and U. (Pfc.) montana Ingram and De Meillon, 1927 were observed feeding on Scl. gutturalis in situ and possible dividing stages of this new parasite were observed in the mosquitoes. This study is the first to describe a dactylosomatid parasite based on morphological and molecular data from Africa as well as observe potential stages in possible dipteran vectors.

6.
Int J Parasitol ; 50(3): 177-194, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32087248

RESUMO

Anuran filarial nematodes are restricted to two comparatively small subfamilies (Icosiellinae and Waltonellinae) of the filariae that currently comprise six genera and 41 recognised species. However, the life histories of only five anuran filarial nematodes, proposed as an ancestral group based on molecular phylogenetic studies, have been elucidated. Furthermore, data on the natural vectors (in situ) and parasite transmission is limited. In the current study we elucidate the life history of Neofoleyellides boerewors n. gen. n. sp. parasitising the guttural toad, Sclerophrys gutturalis and the mosquito vectors Uranotaenia (Pseudoficalbia) mashonaensis and Uranotaenia (Pseudoficalbia) montana. Additionally, we report on the unique host-seeking behaviour of the mosquito vectors which locate their toad hosts using their calls. The complex host-vector relationship and specialised host-seeking behaviour by these mosquitoes indicate biases towards host species and male toad infections.


Assuntos
Anuros/parasitologia , Filariose , Filarioidea/classificação , Animais , Culicidae/parasitologia , Complexo IV da Cadeia de Transporte de Elétrons/genética , Filariose/parasitologia , Filariose/transmissão , Filariose/veterinária , Filarioidea/anatomia & histologia , Filarioidea/genética , Filarioidea/isolamento & purificação , Interações Hospedeiro-Parasita , Estágios do Ciclo de Vida , Microfilárias/isolamento & purificação , Mosquitos Vetores/parasitologia , Nematoides , Filogenia , RNA Ribossômico 18S/genética
7.
Int J Parasitol Parasites Wildl ; 7(2): 213-220, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29988386

RESUMO

Coral reefs harbor the greatest biodiversity per unit area of any ecosystem on earth. While parasites constitute the majority of this biodiversity, they remain poorly studied due to the cryptic nature of many parasites and the lack of appropriate training among coral reef ecologists. Damselfishes (Pomacentridae) are among the most abundant and diverse fishes on coral reefs. In a recent study of blood parasites of Caribbean reef fishes, the first ever apicomplexan blood parasites discovered in damselfishes were reported for members of the genus Stegastes. While these blood parasites were characterized as "Haemohormidium-like", they appear to be distinct from any other known apicomplexan. In this study, we examined host associations, geographic distributions, and provide further insights on the phylogenetic affiliation of this parasite. A combination of morphological characteristics and 18S rDNA sequences suggest that this parasite may be the same species at multiple sites and occurs from the southern to the northern extreme of the eastern Caribbean, although it appears rare in the north. At present it appears to be limited to members of the genus Stegastes and infects all life history stages. It is most common in benthophagous species that occur in high population densities and appears basal to a major monophyletic clade containing species of coccidia, distinct from the Piroplasmida, the order to which Haemohormidium spp. have been assigned. These findings suggest a possible fecal-oral mode of transmission.

8.
Parasit Vectors ; 11(1): 158, 2018 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-29554933

RESUMO

BACKGROUND: Domestic dogs are not native to sub-Saharan Africa, which may account for their susceptibility to Babesia rossi, of which endemic black-backed jackals (Canis mesomelas) are natural reservoirs. There is virtually no information on the occurrence of potentially pathogenic haemogregarines (e.g. Hepatozoon canis) or even rickettsial bacteria (e.g. Ehrlichia spp. and Anaplasma spp.) in indigenous canids in sub-Saharan Africa. Such organisms could pose a risk to domestic dogs, as well as to populations of endangered indigenous canid species. RESULTS: Genomic DNA extracted from blood samples taken from 126 free-ranging and 16 captive black-backed jackals was subjected to reverse line blot (RLB) hybridization assay; 82 (57.8%) specimens reacted only with the Ehrlichia/Anaplasma genera-specific probe. Full-length bacterial 16S rRNA gene of five of these specimens was cloned and the recombinants sequenced. The ten 16S rDNA sequences obtained were most closely related, with approximately 99% identity, to Anaplasma sp. South African Dog, various uncultured Anaplasma spp., as well as various Anaplasma phagocytophilum genotypes. Ninety-one specimens were screened for haemogregarines through PCR amplification using the 18S rRNA gene; 20 (21.9%) specimens reacted positively, of which 14 (15.4%) were confirmed positive for Hepatozoon genotypes from within H. canis. Two (2.2%) specimens were found positive for two different Hepatozoon genotypes. CONCLUSIONS: Sequence analyses confirmed the presence of 16S rDNA sequences closely related to A. phagocytophilum and Anaplasma sp. South African Dog as well as two H. canis genotypes in both free-ranging and captive black-backed jackals. Distinguishing between closely related lineages may provide insight into differences in pathogenicity and virulence of various Anaplasma and H. canis genotypes. By building up a more comprehensive understanding of the range and diversity of the bacteria and eukaryotic organisms (piroplasms and haemogregarines) in the blood of indigenous canids, we may gain insight to such infections in these often-endangered species and the potential for horizontal transmission to and from domestic dogs via ticks where favourable conditions exist.


Assuntos
Anaplasma/isolamento & purificação , Anaplasmose/epidemiologia , Coccidiose/epidemiologia , Eucoccidiida/isolamento & purificação , Chacais , Anaplasma/genética , Anaplasmose/sangue , Anaplasmose/microbiologia , Anaplasmose/parasitologia , Animais , Coccidiose/sangue , Coccidiose/microbiologia , Coccidiose/parasitologia , Doenças do Cão/epidemiologia , Doenças do Cão/microbiologia , Doenças do Cão/parasitologia , Cães , Eucoccidiida/genética , Chacais/microbiologia , Chacais/parasitologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , África do Sul/epidemiologia
9.
Parasitology ; 145(8): 1039-1050, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29198245

RESUMO

Haemogregarines (Apicomplexa: Adeleiorina) are a diverse group of haemoparasites reported from almost all vertebrate classes. The most commonly recorded haemogregarines to parasitize anurans are species of Hepatozoon Miller, 1908. To date 16 Hepatozoon species have been described from anurans in Africa, with only a single species, Hepatozoon hyperolli (Hoare, 1932), infecting a member of the Hyperoliidae. Furthermore, only two Hepatozoon species are known from South African anurans, namely Hepatozoon theileri (Laveran, 1905) and Hepatozoon ixoxo Netherlands, Cook and Smit, 2014, from Amietia delalandii (syn. Amietia quecketti) and three Sclerophrys species, respectively. Blood samples were collected from a total of 225 individuals representing nine hyperoliid species from several localities throughout northern KwaZulu-Natal, South Africa. Twenty frogs from three species were found positive for haemogregarines, namely Afrixalus fornasinii (6/14), Hyperolius argus (2/39), and Hyperolius marmoratus (12/74). Based on morphological characteristics, morphometrics and molecular findings three new haemogregarine species, Hepatozoon involucrum Netherlands, Cook and Smit n. sp., Hepatozoon tenuis Netherlands, Cook and Smit n. sp. and Hepatozoon thori Netherlands, Cook and Smit n. sp., are described from hyperoliid hosts. Furthermore, molecular analyses show anuran Hepatozoon species to be a separate monophyletic group, with species isolated from African hosts forming a monophyletic clade within this cluster.


Assuntos
Anuros/parasitologia , Coccidiose/parasitologia , Eucoccidiida/classificação , Animais , Coccidiose/epidemiologia , DNA de Protozoário/genética , DNA Ribossômico/genética , Eucoccidiida/isolamento & purificação , Eucoccidiida/ultraestrutura , Parasitemia , Filogenia , Reação em Cadeia da Polimerase , África do Sul/epidemiologia
10.
J Parasitol ; 103(4): 366-376, 2017 08.
Artigo em Inglês | MEDLINE | ID: mdl-28395577

RESUMO

Apicomplexan parasites are obligate parasites of many species of vertebrates. To date, there is very limited understanding of these parasites in the most-diverse group of vertebrates, actinopterygian fishes. While DNA barcoding targeting the eukaryotic 18S small subunit rRNA gene sequence has been useful in identifying apicomplexans in tetrapods, identification of apicomplexans infecting fishes has relied solely on morphological identification by microscopy. In this study, a DNA barcoding method was developed that targets the 18S rRNA gene primers for identifying apicomplexans parasitizing certain actinopterygian fishes. A lead primer set was selected showing no cross-reactivity to the overwhelming abundant host DNA and successfully confirmed 37 of the 41 (90.2%) microscopically verified parasitized fish blood samples analyzed in this study. Furthermore, this DNA barcoding method identified 4 additional samples that screened negative for parasitemia, suggesting this molecular method may provide improved sensitivity over morphological characterization by microscopy. In addition, this PCR screening method for fish apicomplexans, using Whatman FTA preserved DNA, was tested in efforts leading to a more simplified field collection, transport, and sample storage method as well as a streamlining sample processing important for DNA barcoding of large sample sets.


Assuntos
Apicomplexa/classificação , Código de Barras de DNA Taxonômico , Doenças dos Peixes/parasitologia , Parasitemia/veterinária , Infecções Protozoárias em Animais/parasitologia , Animais , Apicomplexa/genética , Teorema de Bayes , Recifes de Corais , Código de Barras de DNA Taxonômico/veterinária , DNA de Protozoário/sangue , DNA de Protozoário/química , DNA Ribossômico/química , Doenças dos Peixes/sangue , Doenças dos Peixes/epidemiologia , Peixes , Funções Verossimilhança , Parasitemia/epidemiologia , Parasitemia/parasitologia , Filogenia , Reação em Cadeia da Polimerase/veterinária , Infecções Protozoárias em Animais/sangue , Infecções Protozoárias em Animais/epidemiologia , RNA de Protozoário/genética , RNA Ribossômico 18S/genética , Alinhamento de Sequência , Ilhas Virgens Americanas/epidemiologia
11.
J Eukaryot Microbiol ; 64(2): 193-203, 2017 03.
Artigo em Inglês | MEDLINE | ID: mdl-27480595

RESUMO

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.


Assuntos
Anuros/parasitologia , Coccidiose/parasitologia , Coccidiose/veterinária , Eucoccidiida/ultraestrutura , Doenças dos Animais/parasitologia , Animais , Coccidiose/sangue , DNA de Protozoário/genética , Eritrócitos/parasitologia , Eucoccidiida/classificação , Eucoccidiida/genética , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Filogenia , RNA Ribossômico 18S/genética , Rios , América do Sul , Especificidade da Espécie
12.
Parasit Vectors ; 9(1): 437, 2016 08 08.
Artigo em Inglês | MEDLINE | ID: mdl-27502045

RESUMO

BACKGROUND: Saurian malaria parasites are diverse apicomplexan blood parasites including the family Plasmodiidae Mesnil, 1903, and have been studied since the early 1900s. Currently, at least 27 species of Plasmodium are recorded in African lizards, and to date only two species, Plasmodium zonuriae (Pienaar, 1962) and Plasmodium cordyli Telford, 1987, have been reported from the African endemic family Cordylidae. This paper presents a description of a new malaria parasite in a cordylid lizard and provides a phylogenetic hypothesis for saurian Plasmodium species from South Africa. Furthermore, it provides a tabular review of the Plasmodium species that to date have been formally described infecting species of African lizards. METHODS: Blood samples were collected from 77 specimens of Pseudocordylus melanotus (A. Smith, 1838) from Platberg reserve in the Eastern Free State, and two specimens of Cordylus vittifer (Reichenow, 1887) from the Roodewalshoek conservancy in Mpumalanga (South Africa). Blood smears were Giemsa-stained, screened for haematozoa, specifically saurian malaria parasites, parasite stages were photographed and measured. A small volume was also preserved for TEM studies. Plasmodium and Haemoproteus primer sets, with a nested-polymerase chain reaction (PCR) protocol, were employed to target a fragment of the cytochrome-b (cyt-b) gene region. Resulting sequences of the saurian Plasmodium species' isolates were compared with each other and to other known Plasmodium spp. sequences in the GenBank database. RESULTS: The presence of P. zonuriae in both specimens of the type lizard host C. vittifer was confirmed using morphological characteristics, which subsequently allowed for the species' molecular characterisation. Of the 77 P. melanotus, 44 were parasitised by a Plasmodium species, which when compared morphologically to other African saurian Plasmodium spp. and molecularly to P. zonuriae, supported its description as a new species Plasmodium intabazwe n. sp. CONCLUSIONS: This is the first morphological and molecular account of Plasmodium species within the African endemic family Cordylidae from South Africa. The study highlights the need for molecular analysis of other cordylid Plasmodium species within Africa. Future studies should also include elucidating of the life-cycles of these species, thus promoting the use of both morphological and molecular characteristics in species descriptions of saurian malaria parasites.


Assuntos
Lagartos/parasitologia , Malária/veterinária , Plasmodium/isolamento & purificação , África , Animais , Malária/parasitologia , Filogenia , Plasmodium/classificação , Plasmodium/genética , Plasmodium/crescimento & desenvolvimento , Reação em Cadeia da Polimerase
13.
Parasit Vectors ; 9(1): 347, 2016 06 16.
Artigo em Inglês | MEDLINE | ID: mdl-27305899

RESUMO

BACKGROUND: Within the African monitor lizard family Varanidae, two haemogregarine genera have been reported. These comprise five species of Hepatozoon Miller, 1908 and a species of Haemogregarina Danilewsky, 1885. Even though other haemogregarine genera such as Hemolivia Petit, Landau, Baccam & Lainson, 1990 and Karyolysus Labbé, 1894 have been reported parasitising other lizard families, these have not been found infecting the Varanidae. The genus Karyolysus has to date been formally described and named only from lizards of the family Lacertidae and to the authors' knowledge, this includes only nine species. Molecular characterisation using fragments of the 18S gene has only recently been completed for but two of these species. To date, three Hepatozoon species are known from southern African varanids, one of these Hepatozoon paradoxa (Dias, 1954) shares morphological characteristics alike to species of the family Karyolysidae. Thus, this study aimed to morphologically redescribe and characterise H. paradoxa molecularly, so as to determine its taxonomic placement. METHODS: Specimens of Varanus albigularis albigularis Daudin, 1802 (Rock monitor) and Varanus niloticus (Linnaeus in Hasselquist, 1762) (Nile monitor) were collected from the Ndumo Game Reserve, South Africa. Upon capture animals were examined for haematophagous arthropods. Blood was collected, thin blood smears prepared, stained with Giemsa, screened and micrographs of parasites captured. Haemogregarine morphometric data were compared with the data for named haemogregarines of African varanids. Primer set HepF300 and HepR900 was employed to target a fragment of the 18S rRNA gene and resulting sequences compared with other known haemogregarine sequences selected from the GenBank database. RESULTS: Hepatozoon paradoxa was identified infecting two out of eight (25 %) V. a. albigularis and a single (100 %) V. niloticus examined. Phylogenetic analyses revealed that H. paradoxa clustered with the 'Karyolysus' clade, and not with those of reptilian Hepatozoon spp. CONCLUSIONS: In addition to this being the first morphological and molecular characterisation of a haemogregarine within the African Varanidae, it is the first report of a species of Karyolysus infecting the monitor lizard family. Furthermore, this constitutes now only the third described and named Karyolysus species for which there is a nucleotide sequence available.


Assuntos
Eucoccidiida/classificação , Eucoccidiida/isolamento & purificação , Animais , Análise por Conglomerados , DNA de Protozoário/química , DNA de Protozoário/genética , DNA Ribossômico/química , DNA Ribossômico/genética , Eucoccidiida/citologia , Eucoccidiida/genética , Lagartos/parasitologia , Microscopia , Filogenia , RNA Ribossômico 18S/genética , Análise de Sequência de DNA , África do Sul
14.
Int J Parasitol Parasites Wildl ; 4(1): 135-41, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25830113

RESUMO

Since South Africa boasts a high biodiversity of frog species, a multispecies haemoparasite survey was conducted by screening the blood from 29 species and 436 individual frogs. Frogs were collected at three localities in sub-tropical KwaZulu-Natal, a hotspot for frog diversity. Twenty per cent of the frogs were infected with at least one of five groups of parasites recorded. Intraerythrocytic parasites comprising Hepatozoon, Dactylosoma, and viral or bacterial organisms, as well as extracellular parasites including trypanosomes and microfilarid nematodes were found. A significant difference (P < 0.01) in the prevalence of parasitaemia was found across species, those semi-aquatic species demonstrating the highest, followed by semi-terrestrial frog species. None of those species described as purely terrestrial and aquatic were infected. Hepatozoon and Trypanosoma species accounted for most of the infections, the former demonstrating significant differences in intensity of infection across species, families and habitat types (P = 0.028; P = 0.006; P = 0.007 respectively). Per locality, the first, the formally protected Ndumo Game Reserve, had the highest biodiversity of haemoparasite infections, with all five groups of parasites recorded. The other two sites, that is the area bordering the reserve and the Kwa Nyamazane Conservancy, had a lower diversity with no parasite infections recorded and only Hepatozoon species recorded respectively. Such findings could be ascribed to the anthropogenic impact on the latter two sites, the first by the rural village activities, and the second by the bordering commercial sugar cane agriculture. Future studies should include both morphological and molecular descriptions of the above parasites, as well as the identification of potential vectors, possibly clarifying the effects human activities may have on frog haemoparasite life cycles and as such their biodiversity.

15.
Parasit Vectors ; 7: 552, 2014 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-25526644

RESUMO

BACKGROUND: 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). METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.


Assuntos
Bufonidae , Coccídios/isolamento & purificação , Coccidiose/veterinária , Animais , Coccídios/classificação , Coccidiose/epidemiologia , Coccidiose/parasitologia , África do Sul/epidemiologia
16.
Folia Parasitol (Praha) ; 61(4): 293-300, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25185400

RESUMO

Blood smears prepared from the peripheral blood of 20 wild caught Amietia quecketti (Boulenger) from the North-West University Botanical Gardens, North West Province, South Africa, were examined for the presence of haemogregarines. A haemogregarine species comparative in morphology, host and geographical locality to that of Haemogregarina theileri Laveran, 1905 was detected. The original description of H. theileri was based solely on frog peripheral blood gamont stages. Later, further parasite stages, including trophozoites and merogonic liver stages, were recorded in a related Amietia sp. from equatorial Africa. This species was originally classified as a member of the genus Haemogregarina Danilewsky, 1885, but due to the close life cycle and morphological resemblance to those of Hepatozoon species, H. theileri was later transferred from Haemogregarina to Hepatozoon Miller, 1908. In the present study, meront and merozoite stages not described before, along with previously observed trophozoite, immature and mature gamont stages, are described from the peripheral blood of hosts. In addition, comparative phylogenetic analysis of the partial 18S rDNA sequence of Hepatozoon theileri to those of other haemogregarine species, including those of species of Hepatozoon and a Haemogregarina, support the taxonomic transfer of H. theileri to Hepatozoon, nesting H. theileri within a clade comprising species parasitising other amphibians. This is the first molecular and phylogenetic analysis of an African anuran species of Hepatozoon.


Assuntos
Apicomplexa/classificação , Apicomplexa/isolamento & purificação , Doenças Parasitárias em Animais/parasitologia , Ranidae/parasitologia , Animais , Apicomplexa/genética , DNA de Protozoário/genética , DNA Ribossômico/genética , Filogenia , Especificidade da Espécie
17.
Parasitology ; : 1-10, 2014 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-24923767

RESUMO

SUMMARY Research was undertaken to clarify the true taxonomic position of the terrestrial tortoise apicomplexan, Haemogregarina fitzsimonsi (Dias, 1953). Thin blood films were screened from 275 wild and captive South African tortoises of 6 genera and 10 species between 2009-2011. Apicomplexan parasites within films were identified, with a focus on H. fitzsimonsi. Ticks from wild tortoises, especially Amblyomma sylvaticum and Amblyomma marmoreum were also screened, and sporogonic stages were identified on dissection of adult ticks of both species taken from H. fitzsimonsi infected and apparently non-infected tortoises. Parasite DNA was extracted from fixed, Giemsa-stained tortoise blood films and from both fresh and fixed ticks, and PCR was undertaken with two primer sets, HEMO1/HEMO2, and HepF300/HepR900, to amplify parasite 18S rDNA. Results indicated that apicomplexan DNA extracted from tortoise blood films and both species of tick had been amplified by one or both primer sets. Haemogregarina  fitzsimonsi 18S rDNA sequences from tortoise blood aligned with those of species of Hepatozoon, rather than those of species of Haemogregarina or Hemolivia. It is recommended therefore that this haemogregarine be re-assigned to the genus Hepatozoon, making Hepatozoon fitzsimonsi (Dias, 1953) the only Hepatozoon known currently from any terrestrial chelonian. Ticks are its likely vectors.

18.
Folia Parasitol (Praha) ; 56(3): 173-9, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19827360

RESUMO

Blood films were examined from 154 wild and captive tortoises from four provinces of South Africa, including Gauteng, Kwazulu-Natal, North West and Western Cape. The five species ofchelonians studied were Chersina angulata (Schweigger), Kinixys belliana belliana (Gray), K. lobatsiana Power, K. natalensis Hewitt, and Stigmochelys pardalis (Bell). Two species of haemogregarines, previously reported from Mozambique, were identified in blood films, namely Haemogregarina fitzsimonsi Dias, 1953 and Haemogregarina parvula Dias, 1953. Additional stages of development (trophozoites and probable meronts, merozoites and immature gamonts) in blood preparations from South Africa warranted the redescription of H. fitzsimonsi. A variety of hosts and broad host distribution range were observed for this haemogregarine, with all five species of tortoises parasitized, wild and captive, from all four provinces, in all seasons. In contrast, only two individuals of K. b. belliana and one S. pardalis, all three captive in Kwazulu-Natal, contained H. parvula with encapsulated stages resembling those of Hemolivia mauritanica (Sergent et Sergent, 1904). For H. fitzsimonsi, parasite prevalences, but not parasitaemias, were significantly higher in captive than wild S. pardalis; captive female S. pardalis also showed a significantly greater prevalence of infection than males, but younger, lighter hosts were not significantly more heavily parasitized than older, heavier individuals. The ticks, Amblyomma marmoreum Koch, 1844 and A. sylvaticum (De Geer, 1778), found attached to some tortoises, may prove to be definitive hosts for the two species of haemogregarines observed.


Assuntos
Eucariotos/classificação , Eucariotos/citologia , Tartarugas/parasitologia , Animais , Eucariotos/isolamento & purificação , Feminino , Masculino , África do Sul
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