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1.
Parasitol Res ; 123(4): 174, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38561560

ABSTRACT

Several species of horse flies (Diptera: Tabanidae) are known as vectors of Trypanosoma (Megatrypanum) theileri and T. theileri-like trypanosomes; these host-parasite relationships were established based on the developmental stages of these parasites discovered in the hindgut of horse flies. T. theileri and T. theileri-like trypanosomes have been detected in cattle and wild deer in Japan; however, the vector horse fly species remains unidentified. Therefore, in this study, we aimed to identify the potential horse fly species serving as vectors of T. theileri in Japan. A total of 176 horse flies were collected between June to September 2020 and 2021 in Tokachi, Hokkaido, Japan. The T. theileri infection in the captured horse flies was determined by PCR and microscopic analyses of their midgut and hindgut. Additionally, the trypanosome, microscopically detected in a horse fly, was molecularly characterized and phylogenetically analyzed using 18S rRNA and partial cathepsin L-like protein gene (CATL) sequence of the trypanosome. The microscopy and PCR analyses revealed 0.57% and 35.8% prevalence of T. theileri in horse flies, respectively. Epimastigote stages of T. theileri, adhered to the hindgut epithelial cells of Tabanus chrysurus via flagella or actively moving in the lumen of the gut, were detected. Phylogenetic analysis revealed the connection of isolated trypanosomes with T. theileri in the TthI clade. These results suggest that Ta. chrysurus is a potential vector of T. theileri.


Subject(s)
Deer , Diptera , Trypanosoma , Trypanosomiasis , Animals , Cattle , Trypanosomiasis/epidemiology , Trypanosomiasis/veterinary , Trypanosomiasis/parasitology , Phylogeny , Japan , Deer/parasitology , Diptera/parasitology
2.
Gene ; 913: 148356, 2024 Jun 30.
Article in English | MEDLINE | ID: mdl-38462022

ABSTRACT

Horseflies from the Tabanidae family play a significant role in traditional Chinese medicine to treat various health conditions, including coronary heart disease, stroke, headaches, liver cirrhosis, psoriasis, and hepatic carcinoma. There are 27 species of Tabaninae (Tabanidae) used as medicine, and they showed high morphological similarities with those for which medicinal properties have not been reported. Nonetheless, there have been reports suggesting that medicinal crude drugs sometimes contain irrelevant or false species, impacting the drug's efficacy. In this current study, we collected 14 batches, totaling 13,528 individuals, from various provinces in China. Instead of "classic" DNA barcoding strategy, we employed a high-throughput metabarcoding approach to assess the biological composition of crude drug mixtures derived from horseflies. Our analysis identified 40 Amplicon Sequence Variants (ASVs) with similarity percentages ranging from 92% to 100% with 12 previously reported species. Species delimitation methods revealed the presence of 11 Molecular Operational Taxonomic Units (MOTUs), with ten belonging to the Tabanus genus and one to Hybomitra. Tabanus sp6 displayed the highest relative abundance, and its ASVs showed close resemblance to Tabanus pleski. Our investigations revealed that the medicinal batches were biologically composed of 6 to 12 species. Some batches contained ASVs that closely resembled species previously associated with false Tabanus species. In conclusion, our findings offer valuable insights into the biological composition of crude drugs derived from horseflies and have the potential to enhance the quality of these traditional medicines.


Subject(s)
Diptera , Humans , Animals , Diptera/genetics , Biodiversity , China , DNA Barcoding, Taxonomic
3.
Front Vet Sci ; 9: 920755, 2022.
Article in English | MEDLINE | ID: mdl-36118331

ABSTRACT

Tabanus rubidus (Wiedemann, 1821) (Diptera: Tabanidae) is a hematophagous insect of veterinary and medical importance and is the predominant Tabanus spp. in Thailand. It is a potential mechanical vector of Trypanosoma evansi, which causes surra in domestic and wild animals. Wing geometric morphometrics is widely used as morphological markers for species identification and to assess the insect population structure. Herein, we investigated the intraspecific variation in wing geometry among T. rubidus populations in Thailand using landmark-based geometric morphometric analysis. Tabanus rubidus females were collected from five populations in four geographical regions in Thailand. The left wings of 240 specimens were removed and digitized using 22 landmarks for analysis. While wing size variations were found between some populations, wing shape variations were detected in all. These intraspecific variations in T. rubidus populations indicate an adaptive response to the local environmental conditions.

4.
Insects ; 13(8)2022 Aug 03.
Article in English | MEDLINE | ID: mdl-36005320

ABSTRACT

Tabanidae suck the blood of humans and animals, are important biological vectors for the transmission of diseases, and are of considerable economic and medical significance. However, current knowledge about the mitochondrial genome of this family is limited. More complete mitochondrial genomes of Tabanidae are essential for the identification and phylogeny. Therefore, this study sequenced and analyzed six complete mitochondrial (mt) genome sequences of four genera of Tabanidae for the first time. The complete mt genomes of the six new sequences are circular molecules ranging from 15,851 to 16,107 base pairs (bp) in size, with AT content ranging from 75.64 to 77.91%. The six complete mitochondrial genomes all consist of 13 protein-coding genes (PCGs), 2 ribosomal RNA genes (RRNA), 22 transfer RNA genes (tRNAs), and a control region, making a total of 37 functional subunits. ATT/ATG was the most common start codon, and the stop codon was TAA of all PCGS. All tRNA except tRNA Ser1 had a typical clover structure. Phylogeny was inferred by analyzing the 13 concatenated amino acid sequences of the 22 mt genomes. Bayesian inference, maximum-likelihood trees, and maximum-parsimony inference analyses all showed consistent results. This study supports the concept of monophyly of all genus, ratifies the current taxonomic classification, and provides effective genetic markers for molecular classification, systematics, and genetic studies of Tabanidae.

5.
J Med Entomol ; 59(4): 1217-1235, 2022 07 13.
Article in English | MEDLINE | ID: mdl-35639998

ABSTRACT

Tabanus variegatus F. 1805 has been called by the name Tabanus sulcifronsMacquart 1855 for over 80 yr; T. variegatus is one of the most common large horse flies attacking livestock in much of the southeastern U.S. Morphological, ecological, and molecular evidence indicates that T. variegatus is a distinct species, and we redescribe the female and describe the male. The Fabricius holotype, heavily damaged after over nearly 220 yr, is nevertheless taxonomically sound. Morphology (size, color, palp shape, and r5 wing cell shape) can usually distinguish T. variegatus from T. sulcifrons, but some specimens remain difficult to separate, especially in and west of the Mississippi River Valley. Using geometric morphometric analyses of the wing vein arrangement and palp shape the two species are significantly different. The wings of T. variegatus females also have more microsetae and sometimes a "frosty" appearance. Where they are common and sympatric, as in eastern Tennessee, they are temporally separated such that T. variegatus flies later (August-October) than T. sulcifrons (June-August), minimizing opportunity for gene flow. Museum specimens allow the approximate range of T. variegatus to be compared with that of T. sulcifrons s.l.; T. variegatus is particularly abundant from the coast of the Carolinas and Georgia east to central Tennessee and south to about central Alabama. DNA evidence (COI gene) recovers T. variegatus and T. sulcifrons s.s. in separate clades. Further studies on the T. sulcifrons complex are needed to fully resolve the range of both species, assess the degree of genetic substructuring, and examine relationships with other members of the T. sulcifrons complex.


Subject(s)
Diptera , Alabama , Animals , Environment , Female , Georgia , Male , North America
6.
Acta Parasitol ; 67(1): 518-522, 2022 Mar.
Article in English | MEDLINE | ID: mdl-34196921

ABSTRACT

PURPOSE: The species of the genus Trypanosoma are carried and transmitted by horseflies parasitizing a high diversity of vertebrates. In the Coastal Plain of Rio Grande do Sul, southern Brazil, Tabanus triangulum is the most abundant species and, similarly to the other species of horseflies, there is little knowledge about its vector competence. Therefore, this study aimed to screen the field-collected T. triangulum for the presence of Trypanosoma, to estimate infectivity. METHODS: Horseflies were sampled by the Malaise trap in the forest fragments at the coastal plain and DNA was extracted from whole body flies. The Polymerase Chain Reaction was performed. RESULTS: Horseflies presented amplification of 18S ribosomal gene-specific of Trypanosoma species. DNA sequencing and phylogenetic analysis positioned the strains in the Kaiowa clade with Trypanosoma kaiowa, associated with the crocodilian clade of Trypanosoma. CONCLUSION: This study represents the first report of the presence of the Tr. kaiowa in T. triangulum and the expansion of the parasite's range further south in South America.


Subject(s)
Diptera , Trypanosoma , Animals , Brazil , Phylogeny , Sequence Analysis, DNA , Trypanosoma/genetics
7.
J Equine Vet Sci ; 108: 103807, 2022 01.
Article in English | MEDLINE | ID: mdl-34875427

ABSTRACT

Trypanosoma (Megatrypanum) theileri is a non-pathogenic or weakly pathogenic parasite of domestic cattle that is cyclically transmitted by blood-sucking insects, mainly tabanid flies. It has been reported in several countries like Brazil, Venezuela, Japan, Taiwan, Thailand, Vietnam, and the Philippines. Although the ruminant industry is actively expanded in Malaysia, T. theileri and T. theileri-like trypanosomes have never been reported from Malaysia. The low pathogenicity of this species might be the main reason for overlooking T. theileri in this country. This paper describes an unforeseen finding of T. theileri from the outbreak of T. evansi in the state of Kelantan, Malaysia. This is the first time T. theileri reported in Malaysia, and also the first time T. theileri is reported in equid. Clinical signs compatible with infection by blood protozoa were observed; however, it was uncertain whether they were due to T. theileri infection. The detection of T. theileri from the blood sample and Tabanus sp. were confirmed through molecular analysis with PCR and DNA sequencing. In the present study, T. theileri from one horse and one Tabanus sp. were clustered with sequences of the previously described phylogenetic lineages from Japan, Chad and Brazil cattle. Even though this species is claimed to be host-specific with ruminant host restriction, the finding from this study suggested that T. theileri can infect equine whilst other isolates are known to infect ruminant species only. It is suspected there were two genotypes of T. theileri circulating in at least two districts of Kelantan. Thus, further study on multiple DNA regions should be conducted to determine the strains of detected T. theileri in Malaysia. Its impact on the horse and cattle industry should also be revised.


Subject(s)
Cattle Diseases , Diptera , Horse Diseases , Trypanosoma , Trypanosomiasis , Animals , Cattle , Horses , Malaysia/epidemiology , Phylogeny , Trypanosoma/genetics , Trypanosomiasis/veterinary
8.
Insects ; 12(11)2021 Oct 28.
Article in English | MEDLINE | ID: mdl-34821775

ABSTRACT

Tabanus spp., also known as horse flies (Diptera: Tabanidae), are important vectors of several animal pathogens. Adult females of Tabanus megalops and Tabanus striatus, which are members of the T. striatus complex, are morphologically similar and hence difficult to distinguish using morphological characteristics. In addition, molecular identification by DNA barcoding is also unable to distinguish these species. These two species can occur sympatrically with Tabanus rubidus, which is morphologically similar to T. megalops and T. striatus. Wing geometric morphometrics has been widely used in various insects to distinguish morphologically similar species. This study explored the effectiveness of landmark-based geometrics at distinguishing and identifying T. megalops, T. rubidus, and T. striatus in Thailand. Specimens were collected from different geographical regions of Thailand, and only unambiguously identified specimens were used for geometric morphometric analyses. Left wings of females of T. megalops (n = 160), T. rubidus (n = 165), and T. striatus (n = 85) were photographed, and 22 wing landmarks were used for the analysis. Wing shape was able to distinguish among species with high accuracy scores, ranging from 94.38% to 99.39%. We showed that morphologically very close species of Tabanus can be reliably distinguished by the geometry of their wing venation, and we showed how our experimental material could be used as a reference to tentatively identify new field collected specimens.

9.
Microbiol Spectr ; 9(2): e0051721, 2021 10 31.
Article in English | MEDLINE | ID: mdl-34643449

ABSTRACT

Endosymbiotic Wolbachia bacteria are known to influence the host physiology, microbiota composition, and dissemination of pathogens. We surveyed a population of Tabanus nigrovittatus, commonly referred to as "greenheads," from Crane Beach (Ipswich, MA, USA) for the presence of the alphaproteobacterial symbiont Wolbachia. We studied the COI (mitochondrial cytochrome oxidase) marker gene to evaluate the phylogenetic diversity of the studied specimens. The DNA sequences show strong similarity (between 99.9 and 98%) among the collected specimens but lower similarity to closely related entries in the NCBI database (only between 96.3 and 94.7%), suggesting a more distant relatedness. Low levels of Wolbachia presence necessitated a nested PCR approach, and using 5 markers (ftsZ, fbpA, dnaA, coxA, and gatB), we determined that two recognized "supergroups" of Wolbachia species were represented in the studied specimens, members of clades A and B. Using next-generation sequencing, we also surveyed the insect gut microbiomes of a subset of flies, using Illumina and PacBio 16S rRNA gene sequencing with barcoded primers. The composition of Proteobacteria also varied from fly to fly, with components belonging to Gammaproteobacteria making up the largest percentage of organisms (30 to 70%) among the microbiome samples. Most of the samples showed the presence of Spiroplasma, a member of the phylum Mollicutes, although the frequency of its presence was variable, ranging from 2 to 57%. Another noteworthy bacterial phylum consistently identified was Firmicutes, though the read abundances were typically below 10%. Of interest is an association between Wolbachia presence and higher Alphaproteobacteria representation in the microbiomes, suggesting that the presence of Wolbachia affects the host microbiome. IMPORTANCE Tabanus nigrovittatus greenhead populations contain two supergroups of Wolbachia endosymbionts, members of supergroups A and B. Analysis of the greenhead microbiome using next-generation sequencing revealed that the majority of bacterial species detected belonged to Gammaproteobacteria, with most of the samples also showing the presence of Spiroplasma, a member of the Mollicutes phylum also known to infect insects. An association between Wolbachia presence and higher Alphaproteobacteria representation in the microbiomes suggests that Wolbachia presence affects the host microbiome composition.


Subject(s)
Bacteria/isolation & purification , Diptera/microbiology , Microbiota , Wolbachia/isolation & purification , Animals , Bacteria/classification , Bacteria/genetics , Phylogeny , Wolbachia/classification , Wolbachia/genetics
10.
Parasit Vectors ; 14(1): 453, 2021 Sep 06.
Article in English | MEDLINE | ID: mdl-34488854

ABSTRACT

BACKGROUND: Tabanus bromius (Diptera: Tabanidae) is one of the most notable Tabanidae species of veterinary and medical importance distributed throughout the Palearctic region. In this study, we investigate the genetic diversity and the phylogeographic structure of T. bromius sampled from Turkey, Croatia, and Iran. METHODS: For this purpose, a 686-base-pair (bp) fragment of mitochondrial DNA cytochrome oxidase I gene (COI) and 1339 bp of the nuclear DNA internal transcribed spacer (ITS) were sequenced from 247 individuals representing 15 populations. RESULTS: The sequences generated 169 COI haplotypes and 90 ITS alleles. A higher haplotype/allele diversity (h = 0.9909 for the COI gene and Ad = 0.8193 for the ITS region) compared to a low nucleotide diversity (π = 0.020605 for COI gene and π = 0.013667 for the ITS region), present for a high number of singleton and private haplotypes/alleles imply population expansion in the past. The results of phylogenetic analysis led to the uncovering of geographically significant groupings of lineages with regard to the entrance of the species into Anatolia and the location of major geographic barriers. According to current data, the species appears to have entered Turkey from Caucasia and Iran. A molecular clock applied to the COI data suggests that T. bromius diverged from the outgroup species nearly 8.83 million years ago, around the end of the Miocene era. CONCLUSIONS: The results of this study indicate remarkable genetic diversity across the studied range of the species. High haplotype/allele versus low nucleotide diversity and demographic analyses implied that the T. bromius populations have undergone a series of expansions and retreats in the past. Our current findings suggest that T. bromius split from outgroups around the Late Miocene. Subsequent diversification events during the climatic and environmental fluctuation times of the Late Pliocene and Early Pleistocene periods also significantly influenced the species, resulting in the formation of some major genetic lineages. The phylogenetic analyses indicate that T. bromius most likely entered Turkey from the Caucasus region and Iran.


Subject(s)
Diptera/classification , Diptera/genetics , Genetics, Population , Phylogeny , Animals , DNA, Mitochondrial/genetics , Diptera/physiology , Female , Genes, Mitochondrial , Genetic Variation , Phylogeography , Sequence Analysis, DNA
11.
Biota Neotrop. (Online, Ed. ingl.) ; 21(3): e20211211, 2021. graf
Article in English | LILACS-Express | LILACS | ID: biblio-1285470

ABSTRACT

Abstract: The seasonal population density is informed for two epidemiologically important species of bloodsucking Tabanidae, Tabanus occidentalis Linnaeus and T. pungens Wiedemann, recorded at the Fernando de Noronha archipelago that was never connected to the continent. The two species are widespread in the Neotropical Region, have not been recorded from any other oceanic island, and have most likely been introduced accidentally in the archipelago. Tabanus occidentalis dominated the samples, encompassing 99.6% of the specimens collected in the two local seasons, rainy and dry. Tabanus pungens was rarer, encompassing 0.4% of the specimens collected mainly in the dry season. The tabanids of Fernando de Noronha are able to transmit blood pathogens, bringing risks to the health of the livestock. They also pester the tourists, which brings losses to the local tourist industry. Larvae of both species were already collected in the water lettuce Pistia stratiotes Linnaeus and it is highly recommend that this introduced aquatic plant be removed from the ponds of Fernando de Noronha to control tabanid populations.


Resumo: A densidade populacional e a sazonalidade é informada para duas espécies epidemiologicamente importantes de Tabanidae, Tabanus occidentalis Linnaeus e T. pungens Wiedemann, registradas no arquipélago de Fernando de Noronha, o qual nunca foi conectado ao continente. As duas espécies estão amplamente distribuídas na Região Neotropical, não foram registradas em nenhuma outra ilha oceânica e provavelmente foram introduzidas acidentalmente no arquipélago. Tabanus occidentalis dominou as amostras, englobando 99,6% dos exemplares coletados nas duas estações locais, chuvosa e seca. Tabanus pungens foi mais rara, abrangendo 0,4% dos espécimes coletados principalmente na estação seca. Os tabanídeos de Fernando de Noronha são capazes de transmitir patógenos do sangue, trazendo riscos à saúde do gado. Eles também incomodam os turistas, o que traz prejuízos para a indústria turística local. Larvas de ambas as espécies já foram coletadas na alface d'água Pistia stratiotes Linnaeus e é altamente recomendável que esta planta aquática, introduzida no arquipélago, seja removida das lagoas de Fernando de Noronha para o controle de populações de tabanídeos.

12.
Parasit Vectors ; 13(1): 461, 2020 Sep 10.
Article in English | MEDLINE | ID: mdl-32912281

ABSTRACT

BACKGROUND: More than 170 species of tabanids are known in Europe, with many occurring only in limited areas or having become very rare in the last decades. They continue to spread various diseases in animals and are responsible for livestock losses in developing countries. The current monitoring and recording of horseflies is mainly conducted throughout central Europe, with varying degrees of frequency depending on the country. To the detriment of tabanid research, little cooperation exists between western European and Eurasian countries. METHODS: For these reasons, we have compiled available sources in order to generate as complete a dataset as possible of six horsefly species common in Europe. We chose Haematopota pluvialis, Chrysops relictus, C. caecutiens, Tabanus bromius, T. bovinus and T. sudeticus as ubiquitous and abundant species within Europe. The aim of this study is to estimate the distribution, land cover usage and niches of these species. We used a surface-range envelope (SRE) model in accordance with our hypothesis of an underestimated distribution based on Eurocentric monitoring regimes. RESULTS: Our results show that all six species have a wide range in Eurasia, have a broad climatic niche and can therefore be considered as widespread generalists. Areas with modelled habitat suitability cover the observed distribution and go far beyond these. This supports our assumption that the current state of tabanid monitoring and the recorded distribution significantly underestimates the actual distribution. Our results show that the species can withstand extreme weather and climatic conditions and can be found in areas with only a few frost-free months per year. Additionally, our results reveal that species prefer certain land-cover environments and avoid other land-cover types. CONCLUSIONS: The SRE model is an effective tool to calculate the distribution of species that are well monitored in some areas but poorly in others. Our results support the hypothesis that the available distribution data underestimate the actual distribution of the surveyed species.


Subject(s)
Diptera/classification , Diptera/physiology , Animal Distribution , Animals , Climate , Ecosystem , Europe , Seasons
13.
Med Vet Entomol ; 34(4): 493-497, 2020 12.
Article in English | MEDLINE | ID: mdl-32394541

ABSTRACT

The efficiency and the potential species preference for six different horsefly trap types was studied. A total of 2401 horseflies were collected during this study. The most effective trap was the modified box trap with (27.9%), followed by the Nzi trap with (24.5%), Malaise trap (Townes design 1972) with (22.5)%, canopy trap with (17.9%), modified small canopy trap with (7.0%) and Malaise trap (Townes design 1962) with (0.2%). The Nzi and Malaise trap (Townes design 1972) did not differ significantly in the number of collected horseflies. The comparison of all other traps revealed significant differences in the number of collected horseflies. Tabanus bromius was the most abundant species with (58.6%) of the collected sample. The modified box trap was the most successful in collecting of T. bromius, while the Malaise trap (Townes design 1972) was the most successful in collecting the species Haematopota pluvialis, T. maculicornis and T. tergestinus. This study demonstrated that different trap designs influenced the quantity, species and taxonomic diversity of horseflies that were collected. Variables in the trap design included cloth type and colour and size and shape of trap. More detailed studies should be done to determine which factor or factors are most significant.


Subject(s)
Diptera , Insect Control/methods , Animals , Diptera/classification , Specimen Handling/methods
14.
Acta Trop ; 197: 105069, 2019 Sep.
Article in English | MEDLINE | ID: mdl-31233728

ABSTRACT

Horse flies (Diptera: Tabanidae) are of medical and veterinary importance since they transmit a range of pathogens. The horse fly fauna of tropical Africa is still poorly known, and in some geographical areas has not been studied for decades. This study summarizes the results of tabanid collections performed in three West African countries where only sparse data were previously available, the Central African Republic (CAR), Gabon and Liberia. Of 1093 collected specimens, 28 morphospecies and 26 genospecies belonging to six genera were identified, including the first findings of eleven morphospecies in the countries where horse flies were collected: Philoliche (Subpangonia) gravoti Surcouf, 1908 and Tabanus ianthinus Surcouf, 1907 are new records for Liberia; Ancala fasciata f. mixta (Surcouf, 1914), Tabanus fraternus Macquart, 1846, and T. triquetrornatus Carter, 1915 for CAR; Chrysops longicornis Macquart, 1838, Haematopota albihirta Karsch, 1887, H. bowdeni Oldroyd, 1952, and H. brucei Austen, 1908 for Gabon; and Tabanus secedens f. regnaulti Surcouf, 1912 and T. thoracinus Palisot de Beauvois, 1807 for Gabon and Liberia. Species identification of all 28 morphospecies based on morphological features was further supplemented by barcoding of cytochrome oxidase I (COI). Based on the COI sequences of 115 specimens representing 74 haplotypes, a phylogenetic tree was constructed to illustrate the relationships among the tabanid species found and to demonstrate their intra- and interspecific divergences. Our study enriches the current number of barcoded tabanids with another 22 genospecies. Based on the analysis of molecular data we question the taxonomic relevance of the morphological forms Ancala fasciata f. mixta and Tabanus secedens f. regnaulti. A parasitological survey based on nested PCR of 18S rRNA revealed a high (˜25%) prevalence of Trypanosoma theileri in the studied horse flies, accompanied by two species of monoxenous trypanosomatids, Crithidia mellificae and Blastocrithidia sp.


Subject(s)
Diptera/classification , Trypanosoma/isolation & purification , Africa, Western , Animals , DNA Barcoding, Taxonomic , Diptera/genetics , Diptera/parasitology , Phylogeny , Trypanosoma/genetics
15.
Med Vet Entomol ; 33(2): 269-281, 2019 06.
Article in English | MEDLINE | ID: mdl-30730048

ABSTRACT

The interactions of host, vector and parasite in bovine trypanosomiasis transmission cycles in southwest Nigeria are not yet well understood. Trypanosoma (Trypanosomatida: Trypanosomatidae) species infection prevalences and bloodmeal sources were determined in transmitting vectors of the genera Glossina (Diptera: Glossinidae), Tabanus (Diptera: Tabanidae) and Stomoxys (Diptera: Muscidae) collected using Nzi traps in cattle settlements in southwest Nigeria. Sequenced cytochrome B mitochondrial DNA segments obtained from vector digestive tracts identified bloodmeal sources from eight host species, namely human, cattle, hippopotamus, giraffe, gazelle, spotted hyena, long-tailed rat and one unidentified species. Overall, 71.1% [95% confidence interval (CI) 63.0-78.1], 33.3% (95% CI 21.9-47.0) and 22.2% (95% CI 16.2-29.9), respectively, of Glossina, Tabanus and Stomoxys flies were positive for trypanosomes. The observed trypanosome species were Trypanosoma vivax, Trypanosoma congolense, Trypanosoma brucei, Trypanosoma evansi, Trypanosoma simiae and Trypanosoma godfreyi. Trypanosome DNA was more prevalent in tsetse (34.8% Tr. vivax, 51.1% Tr. b. brucei, 5.2% Tr. congolense, 4.4% Tr. simiae and 24.4% mixed infections) than in other flies and the main determinants in all flies were seasonal factors and host availability. To the best of the present group's knowledge, this is the first report of Trypanosoma species in Tabanus and Stomoxys flies in Nigeria. It indicates that vector control programmes should always consider biting flies along with tsetse flies in the control of human and animal trypanosomiasis.


Subject(s)
Cattle Diseases/transmission , Diptera/parasitology , Trypanosoma/isolation & purification , Trypanosomiasis/veterinary , Animals , Cattle , Cattle Diseases/parasitology , Host-Parasite Interactions , Muscidae/parasitology , Nigeria , Trypanosoma/classification , Trypanosomiasis/parasitology , Trypanosomiasis/transmission , Tsetse Flies/parasitology
16.
Med Vet Entomol ; 33(3): 431-436, 2019 09.
Article in English | MEDLINE | ID: mdl-30775793

ABSTRACT

Equine infectious anaemia (EIA) is a disease with an almost worldwide distribution, with several outbreaks having been reported recently in European countries. In Italy, two regions, Lazio and Abruzzo, are considered as endemic areas for this disease. In nature, the EIA virus is mechanically transmitted by biting flies such as tabanids (Diptera: Tabanidae), although few studies have investigated the epidemiological implications. In the present study, several sites characterized by different levels of EIA prevalence were sampled. In sites with high tabanid populations, a seasonal succession of tabanid species with a dual-peak corresponding to early active species (i.e. in June to July) and late active species (i.e. in August to September) was clearly observed. Moreover, a positive correlation was found between EIA prevalence and tabanid abundance and species richness, suggesting that tabanid diversity might extend the duration of the seasonal transmission period of EIA. Further observations are required to better assess how vector diversity influence EIA transmission.


Subject(s)
Diptera/physiology , Equine Infectious Anemia/epidemiology , Insect Vectors/physiology , Animals , Horses , Italy/epidemiology , Population Dynamics , Prevalence , Seasons
17.
J Med Entomol ; 56(3): 822-827, 2019 04 16.
Article in English | MEDLINE | ID: mdl-30615168

ABSTRACT

Anaplasma phagocytophilum is a pathogen of veterinary and medical importance. It is the causative agent of tick-borne fever (TBF) in ruminants (also known as bovine or ovine granulocytic anaplasmosis), and of human granulocytic anaplasmosis (HGA) in humans. In Europe, A. phagocytophilum is transmitted by Ixodes ricinus (Linnaeus 1758) ticks. The aim of this study was to confirm the presence of A. phagocytophilum DNA in blood-sucking flies belonging to the Tabanidae family using molecular methods. It represents the first detection of this pathogen in Haematopota pluvialis (Linnaeus 1758), Tabanus bromius (Linnaeus 1758), and Tabanus distinguendus (Verrall 1909) in Europe.


Subject(s)
Anaplasma phagocytophilum/isolation & purification , Diptera/microbiology , Animals , Female , Poland
18.
J Med Entomol ; 55(1): 112-121, 2018 01 10.
Article in English | MEDLINE | ID: mdl-29040652

ABSTRACT

Horse flies (Diptera: Tabanidae) are of medical and veterinary importance, as their blood-sucking feeding habit enables them to transmit several disease-causing agents. In Malaysia, the family Tabanidae consists of 120 species belonging to eight genera. The current study describes two new species (Chrysops idlani sp. nov. and Tabanus ekor sp. nov.) and presents new records for seven species: Tabanus fontinalisSchuurmans Stekhoven, 1926; Tabanus fuscifronsSchuurmans Stekhoven, 1926, Tabanus latifasciesSchuurmans Stekhoven, 1926, Tabanus megalops (Walker, 1854), Tabanus rhinargusPhilip, 1962, Tabanus salvazai (Surcouf, 1922), and Tabanus tristisWulp, 1881. Complete descriptions and illustrations are provided for the new species, and species variations for the new records are discussed. Male Tabanus latifasciesSchuurmans Stekhoven, 1926 and Tabanus perakiensis Ricardo, 1911 are thoroughly described herein.


Subject(s)
Animal Distribution , Diptera/classification , Animals , Diptera/anatomy & histology , Female , Malaysia , Male
19.
J Travel Med ; 24(5)2017 Sep 01.
Article in English | MEDLINE | ID: mdl-28931141

ABSTRACT

We report seven Caucasian adult patients who were bitten by horseflies (Tabanus bovinus Linnaeus, 1758) during a trip to Bolivia. Clinical picture was superimposable in all patients: it was characterized by multiple, erythematous, roundish, flattened, large plaques, often with a central point corresponding to horsefly bite, surrounded by satellite, similar, although smaller, lesions. All lesions were located on the neck and/or the upper chest and/or the shoulders; one patient had lesions also on the face. All patients complained of pain at the site of the bite. No systemic symptoms and/or signs were recorded. Rapid recovery was achieved with topical corticosteroids. It is possible that this clinical presentation is pathognomonic of horsefly bites.


Subject(s)
Diptera , Insect Bites and Stings/diagnosis , Travel , Adrenal Cortex Hormones/administration & dosage , Adult , Animals , Bolivia , Dermatologic Agents/administration & dosage , Diagnosis, Differential , Female , Humans , Insect Bites and Stings/drug therapy , Insect Bites and Stings/pathology , Male
20.
J Med Entomol ; 54(2): 471-475, 2017 03 01.
Article in English | MEDLINE | ID: mdl-27707986

ABSTRACT

Putative sensory structures in the food canal, and distal vestibule region entering the canal of Tabanus atratus F., are described. Two pairs of sensilla were observed in the walls of the vestibule-a distal pair of the basiconic type, and a pair of setifiorm sensilla at the base of the vestibule. Vestibular sensilla were constant in type, number, and position. Conversely, setiform sensilla in right and left walls of the food canal varied in number from one fly specimen to another, and lacked evidence of pairing (i.e., sensilla in one wall did not necessarily have a counterpart in the other wall). Food canal sensilla were of setiform design, with the exception of a single basiconic sensilla in each lateral wall of the food canal in every fly. When the food canal was partitioned into four equidistant regions, setiform sensilla were aggregated in the two distal-most regions, with relatively few sensilla observed in the two proximal canal regions. This aggregation was significant, leading to rejection of the null hypothesis that setiform sensilla were evenly distribution throughout the length of the food canal. Basiconic sensilla were always located in the distal-most region of the food canal.


Subject(s)
Diptera/physiology , Sensilla/anatomy & histology , Animals , Diptera/anatomy & histology , Feeding Behavior , Female , Sensilla/physiology
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