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1.
Malar J ; 21(1): 14, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-34986864

RESUMO

BACKGROUND: The order Accipitriformes comprises the largest group of birds of prey with 260 species in four families. So far, 21 haemosporidian parasite species have been described from or reported to occur in accipitriform birds. Only five of these parasite species have been characterized molecular genetically. The first part of this study involved molecular genetic screening of accipitriform raptors from Austria and Bosnia-Herzegovina and the first chromogenic in situ hybridization approach targeting parasites in this host group. The aim of the second part of this study was to summarize the CytB sequence data of haemosporidian parasites from accipitriform raptors and to visualize the geographic and host distribution of the lineages. METHODS: Blood and tissue samples of 183 accipitriform raptors from Austria and Bosnia-Herzegovina were screened for Plasmodium, Haemoproteus and Leucocytozoon parasites by nested PCR, and tissue samples of 23 PCR-positive birds were subjected to chromogenic in situ hybridization using genus-specific probes targeting the parasites' 18S rRNAs. All published CytB sequence data from accipitriform raptors were analysed, phylogenetic trees were calculated, and DNA haplotype network analyses were performed with sequences from clades featuring multiple lineages detected in this host group. RESULTS: Of the 183 raptors from Austria and Bosnia-Herzegovina screened by PCR and sequencing, 80 individuals (44%) were infected with haemosporidian parasites. Among the 39 CytB lineages detected, 18 were found for the first time in the present study. The chromogenic in situ hybridization revealed exo-erythrocytic tissue stages of Leucocytozoon parasites belonging to the Leucocytozoon toddi species group in the kidneys of 14 infected birds. The total number of CytB lineages recorded in accipitriform birds worldwide was 57 for Leucocytozoon, 25 for Plasmodium, and 21 for Haemoproteus. CONCLUSION: The analysis of the DNA haplotype networks allowed identifying numerous distinct groups of lineages, which have not yet been linked to morphospecies, and many of them likely belong to yet undescribed parasite species. Tissue stages of Leucocytozoon parasites developing in accipitriform raptors were discovered and described. The majority of Leucocytozoon and Haemoproteus lineages are specific to this host group, but most Plasmodium lineages were found in birds of other orders. This might indicate local transmission from birds kept at the same facilities (raptor rescue centres and zoos), likely resulting in abortive infections. To clarify the taxonomic and systematic problems, combined morphological and molecular genetic analyses on a wider range of accipitriform host species are needed.


Assuntos
Doenças das Aves/parasitologia , Falconiformes , Haemosporida/isolamento & purificação , Infecções Protozoárias em Animais/parasitologia , Animais , Áustria , Bósnia e Herzegóvina , Haemosporida/classificação , Haemosporida/fisiologia , Filogenia , RNA de Protozoário/análise , RNA Ribossômico 18S/análise , Aves Predatórias , Especificidade da Espécie
2.
Parasitol Res ; 120(12): 4061-4066, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34661730

RESUMO

Rumen flukes have received growing veterinary attention in western and central Europe during the past two decades because of an increase in prevalence of infection in cattle and sheep, including cases of severe clinical disease. Historically, rumen fluke infections in Europe were assumed to be caused mainly by Paramphistomum cervi (or species, which were later considered to be synonymous with P. cervi), but more recently molecular studies demonstrated Calicophoron daubneyi to be the predominating species. For the present investigation, adult rumen flukes isolated from 23 cattle originating from ten farms in Germany (Saxony [1], Baden-Württemberg [4], Bavaria [5]) and one farm in Austria (Tyrol) were analyzed to establish partial sequences of the mitochondrial cytochrome c oxidase subunit I (COI) and the complete sequence of the nuclear internal transcribed spacer 2 (ITS2). Flukes of five animals (dairy cows from three farms in Bavaria) were determined as P. leydeni, and flukes of 18 animals (dairy cows or cattle from cow-calf operations from eight farms in Saxony [1], Baden-Württemberg [4], Bavaria [2], and Tyrol [1]) were identified as C. daubneyi. Based on the molecular analysis of adult rumen flukes collected from cattle, the results of this investigation confirm the common occurrence of C. daubneyi in Germany and reveal the first definitive findings of P. leydeni in Germany and C. daubneyi in Austria.


Assuntos
Doenças dos Bovinos , Paramphistomatidae , Trematódeos , Infecções por Trematódeos , Animais , Áustria/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Código de Barras de DNA Taxonômico , Feminino , Alemanha/epidemiologia , Paramphistomatidae/genética , Rúmen , Ovinos , Infecções por Trematódeos/epidemiologia , Infecções por Trematódeos/veterinária
3.
Malar J ; 20(1): 417, 2021 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-34688278

RESUMO

BACKGROUND: Haemosporidioses are common in birds and their manifestations range from subclinical infections to severe disease, depending on the involved parasite and bird species. Clinical haemosporidioses are often observed in non-adapted zoo or aviary birds, whereas in wild birds, particularly passerines, haemosporidian infections frequently seem to be asymptomatic. However, a recent study from Austria showed pathogenic haemosporidian infections in common blackbirds due to high parasite burdens of Plasmodium matutinum LINN1, a common parasite in this bird species, suggesting that virulent infections also occur in natural hosts. Based on these findings, the present study aimed to explore whether and to what extent other native bird species are possibly affected by pathogenic haemosporidian lineages, contributing to avian morbidity. METHODS: Carcasses of passerine birds and woodpeckers were collected during a citizen science-based survey for avian mortality in Austria, from June to October 2020. Tissue samples were taken and examined for haemosporidian parasites of the genera Plasmodium, Haemoproteus and Leucocytozoon by nested PCR and sequencing the mitochondrial cytb barcode region, histology, and chromogenic in situ hybridization applying genus-specific probes. RESULTS: From over 160 dead bird reportings, 83 carcasses of 25 avian species were submitted for investigation. Overall haemosporidian infection rate was 31%, with finches and tits prevailing species counts and infections. Sequence analyses revealed 17 different haplotypes (4 Plasmodium, 4 Haemoproteus, 9 Leucocytozoon), including 4 novel Leucocytozoon lineages. Most infected birds presented low parasite burdens in the peripheral blood and tissues, ruling out a significant contribution of haemosporidian infections to morbidity or death of the examined birds. However, two great tits showed signs of avian malaria, suggesting pathogenic effects of the detected species Plasmodium relictum SGS1 and Plasmodium elongatum GRW06. Further, exo-erythrocytic tissue stages of several haemosporidian lineages are reported. CONCLUSIONS: While suggesting generally little contribution of haemosporidian infections to mortality of the investigated bird species, the findings indicate a possible role of certain haemosporidian lineages in overall clinical manifestation, either as main causes or as concurrent disease agents. Further, the study presents new data on exo-erythrocytic stages of previously reported lineages and shows how citizen science can be used in the field of haemosporidian research.


Assuntos
Doenças das Aves/mortalidade , Ciência do Cidadão , Haemosporida/fisiologia , Infecções Protozoárias em Animais/epidemiologia , Aves Canoras , Animais , Animais Selvagens , Áustria/epidemiologia , Doenças das Aves/parasitologia , Prevalência , Infecções Protozoárias em Animais/parasitologia
4.
Animals (Basel) ; 11(10)2021 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-34679985

RESUMO

Veterinarians reported cases of cutaneous bleeding in cattle in Austria in the spring and summer of 2020. It was our goal to confirm the tentative diagnosis of parafilariosis by identifying Parafilaria bovicola in exudate samples using molecular methods for the first time in Austria. We asked veterinarians in the field to collect exudate from typical lesions on cattle. We performed polymerase chain reactions (PCRs) and sequenced a 674-bp section of the mitochondrial cytochrome oxidase subunit I in all positive samples. Overall, in 57 of 86 samples, P. bovicola was confirmed by PCR in cattle from Lower Austria, Upper Austria, Styria, Salzburg, Carinthia, and Tyrol. Sequencing detected four different haplotypes or genotypes, respectively, indicating multiple routes of introduction. We conclude that parafilariosis has spread in Austria and we expect that the number of reports of clinical signs and losses due to carcass damage will increase in the future.

6.
Animals (Basel) ; 11(5)2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34070187

RESUMO

Recent studies confirmed that some Hepatozoon-like blood parasites (Apicomplexa) of birds are closely related to the amphibian parasite Lankesterella minima. Little is known about the biology of these pathogens in birds, including their distribution, life cycles, specificity, vectors, and molecular characterization. Using blood samples of 641 birds from 16 species, we (i) determined the prevalence and molecular diversity of Lankesterella parasites in naturally infected birds; (ii) investigated the development of Lankesterella kabeeni in laboratory-reared mosquitoes, Culex pipiens forma molestus and Aedes aegypti; and (iii) tested experimentally the susceptibility of domestic canaries, Serinus canaria, to this parasite. This study combined molecular and morphological diagnostic methods and determined 11% prevalence of Lankesterella parasites in Acrocephalidae birds; 16 Lankesterella lineages with a certain degree of host specificity and two new species (Lankesterella vacuolata n. sp. and Lankesterella macrovacuolata n. sp.) were found and characterized. Lankesterella kabeeni (formerly Hepatozoon kabeeni) was re-described. Serinus canaria were resistant after various experimental exposures. Lankesterella sporozoites rapidly escaped from host cells in vitro. Sporozoites persisted for a long time in infected mosquitoes (up to 42 days post exposure). Our study demonstrated a high diversity of Lankesterella parasites in birds, and showed that several avian Hepatozoon-like parasites, in fact, belong to Lankesterella genus.

7.
Dis Aquat Organ ; 145: 63-77, 2021 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-34137377

RESUMO

A sample of 30 thick-shelled river mussels Unio crassus Philipsson (Unionida: Unionidae) was collected from the River Sauer in Luxembourg to acquire data on parasitic infestations of the mussels. Among other parasites, different development stages of freshwater mites were collected from the gills and the mantle of the mussels and were documented with bright-field, stereo, and confocal laser scanning microscopy and microscopic X-ray computed tomography. The retrieved data allowed a morphological description of larvae and female adults of the mites and assigning them to the genus Unionicola Haldeman (Trombidiformes: Unionicolidae) and the subgenus Pentatax Thor. Additionally, adult stages and larvae were barcoded by sequencing a section of the mitochondrial COI and 18S rRNA genes. This resulted in 4 new, similar Unionicola lineages from the adult stages, which differ in at least 14.7% (uncorrected p distance) from those already published. Barcoding of larval DNA was not successful. The comparison with known European species of the genus Unionicola and analysis of the barcoding results allowed the proposal of a new species of the genus Unionicola. The species was named Unionicola sauerensis sp. nov. after the River Sauer in Luxembourg, where the infested mussels were collected.


Assuntos
Bivalves , Ácaros , Unio , Animais , Feminino , Água Doce , Rios
8.
Transbound Emerg Dis ; 68(6): 3145-3150, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34051130

RESUMO

Aedes albopictus was recorded in Vienna, Austria, in August 2020 for the first time. The species was found to occur in three sites within the city; morphology-based monitoring was followed by DNA-barcoding. Mitochondrial COI barcode sequences recovered three different haplotypes, however this data does not reveal whether single or multiple introduction events have occurred. The vicinity of Viennese Ae. albopictus sites to major traffic routes highlights the importance of passive transport for range expansion of this species.


Assuntos
Aedes , Aedes/genética , Animais , Áustria , Cidades , Haplótipos
9.
Ticks Tick Borne Dis ; 12(4): 101719, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33774481

RESUMO

Free-ranging wild ungulates are widespread in Austria, and act as hosts (i.e. feeding hosts) for ticks, including Ixodes ricinus, and as reservoir hosts for pathogens transmitted by I. ricinus. Due to climate change, the abundance of I. ricinus might be increasing, which could potentially lead to higher prevalences of tick-borne pathogens, such as Babesia spp. and Anaplasma phagocytophilum, some known for their zoonotic potential. Human babesiosis is classified as an emerging zoonosis, but sufficient data of these parasites in central Austria is lacking. In order to assess the abundance of vector-borne pathogens, blood of roe deer (Capreolus capreolus; n = 137), red deer (Cervus elaphus; n = 37), mouflons (Ovis gmelini; n = 2) and chamois (Rupicapra rupicapra; n = 1), was collected and tested for pathogen DNA in two different sampling sites in central Austria. DNA of tick-borne pathogens was detected in 15.5 % (n = 27) of these animals. Babesia capreoli (n = 22 in roe deer; n = 1 in mouflon), Babesia divergens (n = 1, in red deer), and Anaplasma phagocytophilum (n = 4, in roe deer) were detected. DNA sequencing of the 18S rRNA gene of two C. capreolus samples from Upper Austria featured another new genotype of Babesia, which differs in one nucleotide position to B. divergens and B. capreoli, and is intermediate between the main genotypes of B. capreoli and B. divergens within the partial gene sequence analyzed. This study thus confirms that B. capreoli, B. divergens, and A. phagocytophilum are present in free-ranging ungulates in central Austria. Further testing over a longer period is recommended in order to assess the impact of climate change on the prevalence of blood parasites in central Austria.


Assuntos
Anaplasma phagocytophilum/isolamento & purificação , Anaplasmose/epidemiologia , Babesia/isolamento & purificação , Babesiose/epidemiologia , Ehrlichiose/veterinária , Anaplasmose/microbiologia , Animais , Animais Selvagens , Áustria/epidemiologia , Babesiose/microbiologia , Cervos , Ehrlichiose/epidemiologia , Ehrlichiose/microbiologia , Feminino , Masculino , Prevalência , Rupicapra , Carneiro Doméstico
10.
Acta Trop ; 217: 105860, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33587942

RESUMO

Plasmodium relictum is the most common generalist avian malaria parasite, which was reported in over 300 bird species of different orders, particularly often in passerines. This malaria infection is often severe in non-accustomed avian hosts. Currently, five distinct cytochrome b gene lineages have been assigned to P. relictum, with the lineages pSGS1 and pGRW04 being the most common. Based on molecular screenings, the transmission of these two parasite lineages might occur in sympatry, particularly often in sub-Saharan Africa, but they also have been reported to have different areas of transmission globally, with the lineages pSGS1 and pGRW04 being of low (if at all) transmission in huge regions of Americas and Europe, respectively. It remains unclear why these lineages are more often reported in some geographical areas, even though their susceptible vertebrate hosts and vectors are present globally. Co-infections of malaria parasites and other haemosporidians belonging to different species and subgenera are prevalent and even predominate in many bird populations, however, PCR-based protocols using commonly used primers often do not read such co-infections. Because information about the sensitivity of these protocols to read co-infections of the lineages pSGS1 and pGRW04 is absent, this study aimed to unravel this issue experimentally. Blood samples of birds experimentally infected with the single parasite lineages pSGS1 and pGRW04 were used to prepare various combinations of mixes, which were tested by two PCR-based protocols, which have been often used in current avian malaria research. Single infections of the same lineages were used as controls. Careful examination of the sequence electropherograms showed the presence of clear double peaks on polymorphic sites, indicating co-infections. This experiment shows that the broadly used PCR-based protocols can readily distinguish co-infections of these parasite lineages. In other words, the available information about patterns of the geographical distribution of the P. relictum lineages pSGS1 and pGRW04 likely mirrors the existing epidemiological situation but is not a result of the bias due to preferable DNA amplification of one of these lineages during their possible co-infections. This calls for further ecological research aiming determination of factors associated with the transmission of the lineages pSGS1 and pGRW04 in different regions of the globe.


Assuntos
Coinfecção/parasitologia , Internacionalidade , Malária Aviária/parasitologia , Plasmodium/genética , Plasmodium/isolamento & purificação , Reação em Cadeia da Polimerase , Animais , Citocromos b/genética , Filogenia , Plasmodium/fisiologia
11.
Front Vet Sci ; 7: 591943, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33195629

RESUMO

Vector-borne diseases of zoonotic and/or veterinary relevance have been increasingly reported in horses globally, although data regarding working and military horses is lacking. Portuguese military horses may constitute a risk group for these pathogens, as they frequently work outdoors in various regions of the country. This study included 101 apparently healthy horses belonging to the Portuguese National Republican Guard. Blood samples were analyzed to determine the presence and prevalence of piroplasms, Anaplasmataceae, Rickettsia spp., and filarioid helminths. Overall 32.7% of the horses gave positive results for Theileria equi. Two genotypes of T. equi were verified. No positive results were recorded for Anaplasma spp., Rickettsia spp., filarioid helminthes, and Babesia caballi. As equine piroplasmosis is a severe infectious tick-borne disease responsible for significant losses in equine production and with numerous impacts in the international movement of horses, adequate treatment, and preventive measures are needed to reduce exposure to vectors and future infections.

12.
J Zool Syst Evol Res ; 58(3): 633-647, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33041524

RESUMO

The land snail genus Schileykula Gittenberger, 1983 is distributed in arid limestone areas from western Turkey to north-western Iran. It comprises eight species, which display high variation in shell size and morphology. The cylindrical shells are 5-12 mm in height and the last shell whorls bear several inner lamellae and plicae. Two taxa differ in their chirality having sinistral shells, while all the others are dextrals such as the vast majority of orculids. The aim of this study was to establish a molecular genetic phylogeny of Schileykula and to test whether it conforms to the current morphology-based classification. Furthermore, we were interested in the phylogenetic position of the two sinistral forms in order to assess whether one or two reversals happened in the evolution of the genus. Nine out of ten species, including all four subspecies of Schileykula trapezensis and three of six subspecies of Schileykula scyphus, were investigated. A section of the mitochondrial cytochrome c oxidase subunit I gene was analyzed in 54 specimens of Schileykula and from a subsample, partial sequences of the mitochondrial genes for the 12S rRNA and the 16S rRNA, and a section of the nuclear H4/H3 histone gene cluster were obtained. The phylogenetic trees based on the mitochondrial sequences feature high support values for most nodes, and the species appear well differentiated from each other. The two chiral forms evolved independently and are not sister lineages. However, some groupings disagree with the present morphology-based classification and taxonomical conclusions are drawn. Schileykula trapezensis is polyphyletic in the molecular genetic trees; therefore, three of its subspecies are elevated to species level: Schileykula acampsis Hausdorf, 1996 comb. nov., Schileykula neuberti Hausdorf, 1996 comb. nov., and Schileykula contraria Neubert, 1993 comb. nov. Furthermore, Schileykula sigma is grouped within S. scyphus in the mitochondrial and nuclear trees and consequently treated as a subspecies of the latter (Schileykula scyphus sigma Hausdorf, 1996 comb. nov.). Schileykula nordsiecki, whose shell morphology is indistinguishable from that of the neighboring Schileykula scyphus lycaonica, but who differs in its genital anatomy, was confirmed to represent a distinct lineage. The phylogenies produced by the mitochondrial and nuclear data sets are to some extent conflicting. The patterns differ concerning the grouping of some specimens, suggesting at least two independent hybridization events involving S. contraria, S. scyphus and S. trapezensis. The results exemplify the importance of integrating both mitochondrial and nuclear sequence data in order to complement morphology-based taxonomy, and they provide further evidence for hybridization across distantly related lineages in land snails.

13.
Parasitol Res ; 119(12): 4291-4295, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33057813

RESUMO

Fecal samples of 177 calves of up to 180 days of age with diarrhea from 70 farms in Austria were examined to obtain information on the occurrence of Cryptosporidium species. Initially, all samples were examined by phase-contrast microscopy. Cryptosporidium-positive samples (55.4%; n = 98) were screened by gp60 PCR, resulting in 68.4% (n = 67) C. parvum-positive samples. The remaining 31 gp60-PCR-negative and the phase-contrast microscopy negative samples (n = 79) were screened by PCR targeting a 700 bp fragment of the 18S rRNA gene. Sequencing of the PCR products revealed the presence of C. parvum (n = 69), C. ryanae (n = 11), and C. bovis (n = 7). The latter two species have never been described in Austria. C. parvum-positive samples were genotyped at the gp60 gene locus, featuring four subtypes (IIaA15G2R1, IIaA21G2R1, IIaA19G2R1, IIaA14G1R1). The most frequently detected subtype IIaA15G2R1 (n = 52) was present in calves from 30 different farms. IIaA14G1R1 (n = 5) occurred on a single farm, subtype IIaA21G2R1 (n = 4) on two farms, and subtype IIaA19G2R1 (n = 4) on three farms. The results confirm the widespread occurrence of zoonotic C. parvum in diarrheic calves.


Assuntos
Doenças dos Bovinos/parasitologia , Criptosporidiose/parasitologia , Cryptosporidium/classificação , Cryptosporidium/isolamento & purificação , Animais , Áustria/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Criptosporidiose/epidemiologia , Cryptosporidium/citologia , Cryptosporidium/genética , Diarreia/parasitologia , Diarreia/veterinária , Fazendas , Fezes/parasitologia , Genótipo , Proteínas de Protozoários/genética , RNA Ribossômico 18S/genética
14.
Malar J ; 19(1): 335, 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32933526

RESUMO

BACKGROUND: Haemosporidians (Apicomplexa, Protista) are obligate heteroxenous parasites of vertebrates and blood-sucking dipteran insects. Avian haemosporidians comprise more than 250 species traditionally classified into four genera, Plasmodium, Haemoproteus, Leucocytozoon, and Fallisia. However, analyses of the mitochondrial CytB gene revealed a vast variety of lineages not yet linked to morphospecies. This study aimed to analyse and discuss the data of haemosporidian lineages isolated from birds of the family Turdidae, to visualise host and geographic distribution using DNA haplotype networks and to suggest directions for taxonomy research on parasite species. METHODS: Haemosporidian CytB sequence data from 350 thrushes were analysed for the present study and complemented with CytB data of avian haemosporidians gathered from Genbank and MalAvi database. Maximum Likelihood trees were calculated to identify clades featuring lineages isolated from Turdidae species. For each clade, DNA haplotype networks were calculated and provided with information on host and geographic distribution. RESULTS: In species of the Turdidae, this study identified 82 Plasmodium, 37 Haemoproteus, and 119 Leucocytozoon lineages, 68, 28, and 112 of which are mainly found in this host group. Most of these lineages cluster in the clades, which are shown as DNA haplotype networks. The lineages of the Leucocytozoon clades were almost exclusively isolated from thrushes and usually were restricted to one host genus, whereas the Plasmodium and Haemoproteus networks featured multiple lineages also recovered from other passeriform and non-passeriform birds. CONCLUSION: This study represents the first attempt to summarise information on the haemosporidian parasite lineages of a whole bird family. The analyses allowed the identification of numerous groups of related lineages, which have not been linked to morphologically defined species yet, and they revealed several cases in which CytB lineages were probably assigned to the wrong morphospecies. These taxonomic issues are addressed by comparing distributional patterns of the CytB lineages with data from the original species descriptions and further literature. The authors also discuss the availability of sequence data and emphasise that MalAvi database should be considered an extremely valuable addition to GenBank, but not a replacement.


Assuntos
Doenças das Aves/epidemiologia , Haemosporida/fisiologia , Interações Hospedeiro-Parasita , Infecções Protozoárias em Animais/epidemiologia , Aves Canoras , Animais , Doenças das Aves/parasitologia , Filogeografia , Prevalência , Infecções Protozoárias em Animais/parasitologia
15.
Dis Aquat Organ ; 139: 103-111, 2020 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-32351241

RESUMO

Acanthocephalan parasites were collected from the intestinal tracts of 137 predominantly wild fish (1 barbel Barbus barbus, 3 European chub Squalius cephalus, 13 rainbow trout Oncorhynchus mykiss and 120 brown trout Salmo trutta) from 12 localities. The condition factor, intensity of acanthocephalan infection and pathological lesions, if applicable, were documented. Routine bacteriology and virology were performed, and the brown trout were additionally tested for the presence of the myxozoan parasite Tetracapsolioides bryosalmonae by PCR. In total, 113 acanthocephalans were barcoded by sequencing a section of the mitochondrial cytochrome oxidase subunit I (COI) gene. Barcoding of the acanthocephalan tissues resulted in 77 sequences, of which 56 were assigned to Echinorhynchus truttae (3 genotypes), 11 to Pomphorhynchus tereticollis (9 genotypes), 9 to Acanthocephalus sp. (5 genotypes) and 1 to Neoechinorhynchida. Most of these genotypes were detected for the first time. Statistically, the acanthocephalan infection did not have an impact on the condition factor of the brown trout. Infection with P. tereticollis caused more severe pathological changes in the digestive tract than E. truttae. The present study provides new data regarding the distribution of acanthocephalan species in Austria and their impact on individual fish. In addition, new barcoding data from acanthocephalan parasites are presented, and the occurrence of P. tereticollis in European chub in Austria and in brown and rainbow trout in general was confirmed for the first time.


Assuntos
Acantocéfalos , Doenças dos Peixes , Oncorhynchus mykiss , Animais , Áustria , Doenças dos Peixes/parasitologia
16.
Malar J ; 19(1): 69, 2020 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-32050970

RESUMO

BACKGROUND: Passerine birds are frequently infected with diverse haemosporidian parasites. While infections are traditionally considered benign in wild birds, recent studies demonstrated mortalities of passerine species due to exo-erythrocytic development of the parasites, which can damage organs in affected hosts. However, exo-erythrocytic development remains insufficiently investigated for most haemosporidian species and thus little is known about the virulence of tissue stages in wild passerine birds. The aim of the present study was to investigate natural haemosporidian infections in deceased Eurasian blackbirds (Turdus merula) and song thrushes (Turdus philomelos) and to determine parasite burden and associated histological effects. METHODS: For molecular analysis, blood and tissue samples from 306 thrushes were screened for Plasmodium, Haemoproteus and Leucocytozoon parasites by nested PCR. For the detection of parasite stages in organ samples, tissue sections were subjected to chromogenic in situ hybridization (CISH) using genus- and species-specific probes targeting the rRNAs of parasites. Exo-erythrocytic parasite burden was semi-quantitatively assessed and histological lesions were evaluated in haematoxylin-eosin-stained sections. RESULTS: By PCR, 179 of 277 Eurasian blackbirds and 15 of 29 song thrushes were positive for haemosporidians. Parasites of all three genera were detected, with Plasmodium matutinum LINN1 and Plasmodium vaughani SYAT05 showing the highest prevalence. CISH revealed significant differences in exo-erythrocytic parasite burden between lineages in Eurasian blackbirds, with P. matutinum LINN1 frequently causing high exo-erythrocytic parasite burdens in various organs that were associated with histological alterations. Song thrushes infected with P. matutinum LINN1 and birds infected with other haemosporidian lineages showed mostly low exo-erythrocytic parasite burdens. Two Eurasian blackbirds infected with Leucocytozoon sp. TUMER01 showed megalomeronts in various organs that were associated with inflammatory reactions and necroses. CONCLUSION: This study suggests that P. matutinum LINN1, a common lineage among native thrushes, regularly causes high exo-erythrocytic parasite burdens in Eurasian blackbirds, which may result in disease and mortalities, indicating its high pathogenic potential. The findings further illustrate that the same parasite lineage may show different levels of virulence in related bird species which should be considered when assessing the pathogenicity of haemosporidian parasite species. Finally, the study provides evidence of virulent Leucocytozoon sp. TUMER01 infections in two Eurasian blackbirds caused by megalomeront formation.


Assuntos
Doenças das Aves/parasitologia , Haemosporida/fisiologia , Infecções Protozoárias em Animais/parasitologia , Aves Canoras/parasitologia , Animais , Animais Selvagens , Áustria , Bolsa de Fabricius/parasitologia , DNA de Protozoário/genética , DNA de Protozoário/isolamento & purificação , Haemosporida/genética , Haemosporida/isolamento & purificação , Haemosporida/patogenicidade , Coração/parasitologia , Hibridização In Situ/métodos , Hibridização In Situ/veterinária , Rim/parasitologia , Plasmodium/classificação , Plasmodium/genética , Plasmodium/isolamento & purificação , Reação em Cadeia da Polimerase/veterinária , Especificidade da Espécie , Virulência
17.
Vet Parasitol Reg Stud Reports ; 19: 100370, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-32057397

RESUMO

The domestic yak Bos mutus grunniens is an important livestock animal in parts of Asia, especially of the Himalayan region, where people rely on it for meat, wool, milk and labour. In its countries of origin, the yak is commonly infected with the ascarid Toxocara vitulorum. This parasite mainly infects cattle (Bos taurus) and domestic buffalo (Bubalus bubalus) and is most commonly found in sub-tropical regions, but has been occasionally reported in more temperate climates, including several Central European countries. Here we describe a fatal case of toxocarosis in a yak calf in Tyrol in May 2018, which is the first report of these parasites in yaks in Austria. A moribund calf had to be euthanized and gross pathology showed masses of cream-coloured, up to 25 cm long nematodes filling the whole of the small intestine, as well as parts of the colon. PCR of parts of the mitochondrial cytochrome c oxidase subunit I gene was performed and sequence analysis confirmed the helminths as Toxocara vitulorum.


Assuntos
Doenças dos Bovinos/diagnóstico , Toxocara/isolamento & purificação , Toxocaríase/diagnóstico , Animais , Áustria , Bovinos , Doenças dos Bovinos/parasitologia , Evolução Fatal , Masculino , Toxocaríase/parasitologia
18.
Cladistics ; 36(6): 594-616, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34618978

RESUMO

The Geomitrini is the most species-rich group of land snails in the Madeiran Archipelago. The phylogeny of the group is reconstructed based on mitochondrial and nuclear genetic markers. The timing of diversification, the colonisation history of the islands of the Madeiran Archipelago and the evolution of characters of the dart apparatus are studied. The results of the phylogenetic analyses confirm the sister group relationship of Geomitrini and Cochlicellini, but also show that several previously accepted genus-group taxa are not monophyletic. A new classification for the Geomitrini is proposed, including the description of two new genera, Domunculifex Brozzo, De Mattia, Harl & Neiber, n. gen. and Testudodiscula Brozzo, De Mattia, Harl & Neiber, n. gen. The onset of diversification of Geomitrini was dated in our analysis at 13 Ma, which largely coincides with the emergence of the present-day islands. The ancestral state estimation recovered the presence of two appendiculae in the reproductive system as the ancestral state in Geomitrini. One appendicula was lost three times independently within the tribe and is even missing completely in one group. The ancestral area estimation suggests recurrent colonisations of Madeira (and the Ilhas Desertas) from the older island Porto Santo.

19.
Parasitol Res ; 119(2): 447-463, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31883048

RESUMO

In this study, we explore blood parasite prevalence, infection intensity, and co-infection levels in an urban population of feral pigeons Columba livia in Cape Town. We analyze the effect of blood parasites on host body condition and the association between melanin expression in the host's plumage and parasite infection intensity and co-infection levels. Relating to the haemosporidian parasite itself, we study their genetic diversity by means of DNA barcoding (cytochrome b) and show the geographic and host distribution of related parasite lineages in pigeons worldwide. Blood from 195 C. livia individuals was collected from April to June 2018. Morphometric measurements and plumage melanism were recorded from every captured bird. Haemosporidian prevalence and infection intensity were determined by screening blood smears and parasite lineages by DNA sequencing. Prevalence of Haemoproteus spp. was high at 96.9%. The body condition of the hosts was negatively associated with infection intensity. However, infection intensity was unrelated to plumage melanism. The cytochrome b sequences revealed the presence of four Haemoproteus lineages in our population of pigeons, which show high levels of co-occurrence within individual birds. Three lineages (HAECOL1, COLIV03, COQUI05) belong to Haemoproteus columbae and differ only by 0.1% to 0.8% in the cytochrome b gene. Another lineage (COLIV06) differs by 8.3% from the latter ones and is not linked to a morphospecies, yet. No parasites of the genera Leucocytozoon and Plasmodium were detected.


Assuntos
Doenças das Aves/parasitologia , Columbidae/parasitologia , Variação Genética , Haemosporida/genética , Infecções Protozoárias em Animais/parasitologia , Animais , Doenças das Aves/epidemiologia , Citocromos b/genética , Prevalência , Infecções Protozoárias em Animais/epidemiologia , África do Sul/epidemiologia
20.
Malar J ; 18(1): 305, 2019 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-31481072

RESUMO

BACKGROUND: Plasmodium species feature only four to eight nuclear ribosomal units on different chromosomes, which are assumed to evolve independently according to a birth-and-death model, in which new variants originate by duplication and others are deleted throughout time. Moreover, distinct ribosomal units were shown to be expressed during different developmental stages in the vertebrate and mosquito hosts. Here, the 18S rDNA sequences of 32 species of avian haemosporidian parasites are reported and compared to those of simian and rodent Plasmodium species. METHODS: Almost the entire 18S rDNAs of avian haemosporidians belonging to the genera Plasmodium (7), Haemoproteus (9), and Leucocytozoon (16) were obtained by PCR, molecular cloning, and sequencing ten clones each. Phylogenetic trees were calculated and sequence patterns were analysed and compared to those of simian and rodent malaria species. A section of the mitochondrial CytB was also sequenced. RESULTS: Sequence patterns in most avian Plasmodium species were similar to those in the mammalian parasites with most species featuring two distinct 18S rDNA sequence clusters. Distinct 18S variants were also found in Haemoproteus tartakovskyi and the three Leucocytozoon species, whereas the other species featured sets of similar haplotypes. The 18S rDNA GC-contents of the Leucocytozoon toddi complex and the subgenus Parahaemoproteus were extremely high with 49.3% and 44.9%, respectively. The 18S sequences of several species from all three genera showed chimeric features, thus indicating recombination. CONCLUSION: Gene duplication events leading to two diverged main sequence clusters happened independently in at least six out of seven avian Plasmodium species, thus supporting evolution according to a birth-and-death model like proposed for the ribosomal units of simian and rodent Plasmodium species. Patterns were similar in the 18S rDNAs of the Leucocytozoon toddi complex and Haemoproteus tartakovskyi. However, the 18S rDNAs of the other species seem to evolve in concerted fashion like in most eukaryotes, but the presence of chimeric variants indicates that the ribosomal units rather evolve in a semi-concerted manner. The new data may provide a basis for studies testing whether differential expression of distinct 18S rDNA also occurs in avian Plasmodium species and related haemosporidian parasites.


Assuntos
Aves/parasitologia , DNA de Protozoário/análise , Haemosporida/genética , RNA Ribossômico 18S/análise , Animais , Doenças das Aves/parasitologia , Núcleo Celular/genética , DNA Ribossômico/análise , Filogenia , Plasmodium/genética , Especificidade da Espécie
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