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1.
Exp Parasitol ; 223: 108081, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33549536

RESUMO

Artificial breeding of small yellow croaker (Larimichthys polyactis) was recently achieved, providing a bright future for its commercial farming. In May 2019, a disease outbreak occurred among small yellow croakers in an aquaculture farm near Xiangshan Bay, charactering by white spots spotted on the surface of fish skin, gills and fins. The parasite was preliminarily identified as Cryptocaryon irritans based on morphological feature of the parasite and the symptoms on fish. However, the previously published specific primer pairs failed to confirm the existence of C. iriitans. Six nucleotides mismatches were discovered after mapping specific forward primer back to targeted gene. Therefore, an updated PCR specific primer was developed within the 9th highly variable region of 18S rRNA gene and conserved in all C. irritans sequences available in GenBank database. The specificity was verified in silico by Primer-BLAST against GenBank nucleotide. Laboratory cultured ciliates (Mesanophrys, Pseudokeronopsis and Uronema) as well as natural microbial community samples collected from sea water and river water was used as negative control to verify the specificity of the primer in situ. Besides, tank transfer method was used to evaluate the treatment of the parasite infection. By tank transfer method, 2.00 ± 0.61 out of 10 fish that already sever infected were successfully survived after 8 days treatment, meanwhile the control group died out at d 6. More loss to the treatment group during first five days was observed and may attribute to the combined effect from infection and stress the recent domesticated fish suffered during rotation. Therefore, tank transfer method was also effective to prevent small yellow croaker from further infection, however the loss of the small yellow croaker suffered from stress during rotation also needs to be carefully concerned. In conclusion, this study reported the first diagnose of C. irritans infection on small yellow croaker, provided updated specific primer to detect C. irritans infection on fish body and reported the effect of tank transfer on small yellow croaker treatment.


Assuntos
Infecções por Cilióforos/veterinária , Cilióforos/isolamento & purificação , Doenças dos Peixes/parasitologia , Perciformes/parasitologia , Nadadeiras de Animais/parasitologia , Nadadeiras de Animais/patologia , Animais , China/epidemiologia , Cilióforos/classificação , Cilióforos/genética , Infecções por Cilióforos/diagnóstico , Infecções por Cilióforos/epidemiologia , Infecções por Cilióforos/parasitologia , Surtos de Doenças/veterinária , Doenças dos Peixes/diagnóstico , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/terapia , Pesqueiros , Brânquias/parasitologia , Brânquias/patologia , Músculo Esquelético/parasitologia , Músculo Esquelético/patologia , Filogenia , RNA Ribossômico 18S/genética , Pele/parasitologia , Pele/patologia , Especificidade da Espécie
2.
Protist ; 171(3): 125740, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32544844

RESUMO

We report the discovery of three new species of freshwater metopid ciliates, Pileometopus lynni gen. et sp. nov., Castula flexibilis gen. et sp. nov., and Longitaenia australis gen. et sp. nov. Based on morphologic features and the 18S rRNA gene phylogeny, we transfer two known species of Metopus to the new genus Castula, as C. fusca (Kahl, 1927) comb. nov. and C. setosa (Kahl, 1927) comb. nov. and another known species is herein transferred to the new genus Longitaenia, as L. gibba (Kahl, 1927) comb. nov. Pileometopus is characterized by a turbinate body shape, a dorsal field of densely spaced dikinetids, a bipartite paroral membrane, and long caudal cilia. A distinctive morphologic feature of Castula species is long setae arising over the posterior third of the body (as opposed to a terminal tuft). Longitaenia spp. are characterized by an equatorial cytostome and long perizonal ciliary stripe relative to the cell length. Based on phylogenetic analyses of 18S rRNA gene sequences, we identify and briefly discuss strongly supported clades and intraspecific genetic polymorphism within the order Metopida.


Assuntos
Cilióforos/classificação , Filogenia , Cilióforos/citologia , Cilióforos/isolamento & purificação , Água Doce/microbiologia , Filogeografia , RNA Ribossômico 18S/genética
3.
Protist ; 171(3): 125739, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32535352

RESUMO

'Flagship' ciliates were investigated from soil samples collected in Florida, USA. This was undertaken to determine if species thought to be restricted to a given world region could be uncovered from similar habitats in a novel location, e.g. another continent. Two species of Condylostomides were discovered, and recorded from the North American continent for the first time. Condylostomides etoschensis was known only from Africa, but was found to be thriving in a Florida study site. An 18S rDNA sequence for this species was determined for the first time. Also discovered from the same study site was the ciliate Condylostomides coeruleus, previously known only from Central and South America. These two 'flagship' ciliates were found in the same habitat, from a continent well outside of their previously recorded biogeographies. Molecular sequencing and microscopy investigations were conducted to form the baseline for future work within this genus. Soil ciliates can obtain large population numbers and form cysts and are therefore likely able to disperse globally. These new records provide additional evidence that large distances, even between continents, do not hinder microbes from thriving globally. The absence of these conspicuously-colored gold and blue ciliates from previous studies is likely due to undersampling, rather than to any physical barriers.


Assuntos
Cilióforos , Filogenia , Microbiologia do Solo , Cilióforos/classificação , Cilióforos/isolamento & purificação , Cistos , Florida , América do Norte , Filogeografia , RNA Ribossômico 18S/genética
4.
Int J Syst Evol Microbiol ; 70(6): 3939-3952, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32441613

RESUMO

The spirotrichean ciliate Stylonychia notophora has previously been recorded in India although the descriptions are lacking in detail. It has been suggested several times that the Indian population, S. notophora sensu Sapra and Dass, 1970 collected along the Delhi stretch of the River Yamuna, is identical to Tetmemena pustulata, but this has never been confirmed due to insufficient data for the former. The present study includes detailed descriptions (classical and molecular) of populations of Tetmemena isolated from six locations along the River Yamuna, India. These include four from the Delhi stretch including that from which Sapra and Dass, 1970 isolated their population of S. notophora. Due to the lack of a sufficiently detailed description, the taxonomic status of S. notophora sensu Sapra and Dass, 1970 was not clear. Comparisons among the populations isolated in the present study with previous descriptions of T. pustulata and S. notophora sensu Sapra and Dass, 1970 show only minor differences in morphometry, morphogenesis and in 18S rDNA sequences. The 18S rDNA sequences of all six populations had 99% similarity to both T. pustulata and S. notophora. These findings support the contention that S. notophora sensu Sapra and Dass, 1970 was misidentified and is a population of T. pustulata. This study supports the need for adopting an integrative approach based on morphological, morphogenetic and molecular data in order to understand species delimitation in ciliated protists.


Assuntos
Cilióforos/classificação , Filogenia , Cilióforos/isolamento & purificação , DNA Ribossômico/genética , Índia , Rios , Análise de Sequência de DNA
5.
Int J Syst Evol Microbiol ; 70(4): 2515-2530, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32118526

RESUMO

Two poorly known tintinnine ciliates collected from the coastal waters of PR China, viz., Codonellopsis mobilis Wang, 1936 and Tintinnopsis chinglanensis Nie & Ch'eng, 1947, were redescribed and neotypified using live observation, protargol staining and SSU rRNA gene sequencing. Ciliature information and SSU rRNA gene sequence data of both species were revealed for the first time and improved diagnoses were given based on the original descriptions and data from the present study. Further phylogenetic analyses inferred from SSU rRNA gene sequences and morphological data suggested that the genus Tintinnopsis is polyphyletic and that the genus Codonellopsis is non-monophyletic. The approximately unbiased test, however, does not reject the possibility that Codonellopsis is monophyletic.


Assuntos
Cilióforos/classificação , Filogenia , Água do Mar , Composição de Bases , China , Cilióforos/isolamento & purificação , DNA de Protozoário/genética , DNA Ribossômico/genética , Genes de RNAr , Análise de Sequência de DNA , Proteínas de Prata
6.
BMC Evol Biol ; 20(1): 37, 2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-32171235

RESUMO

BACKGROUND: Various ecological groups of earthworms very likely constitute sharply isolated niches that might permit speciation of their symbiotic ciliates, even though no distinct morphological features appear to be recognizable among ciliates originating from different host groups. The nuclear highly variable ITS1-5.8S-ITS2 region and the hypervariable D1/D2 region of the 28S rRNA gene have proven to be useful tools for the delimitation of species boundaries in closely related free-living ciliate taxa. In the present study, the power of these molecular markers as well as of the secondary structure of the ITS2 molecule were tested for the first time in order to discriminate the species of endosymbiotic ciliates that were isolated from the gastrointestinal tract of three ecologically different groups of lumbricid earthworms. RESULTS: Nineteen new ITS1-5.8S-ITS2 region and D1/D2-28S rRNA gene sequences were obtained from five astome species (Anoplophrya lumbrici, A. vulgaris, Metaradiophrya lumbrici, M. varians, and Subanoplophrya nodulata comb. n.), which were living in the digestive tube of three ecological groups of earthworms. Phylogenetic analyses of the rRNA locus and secondary structure analyses of the ITS2 molecule robustly resolved their phylogenetic relationships and supported the distinctness of all five species, although previous multivariate morphometric analyses were not able to separate congeners in the genera Anoplophrya and Metaradiophrya. The occurrence of all five taxa, as delimited by molecular analyses, was perfectly correlated with the ecological groups of their host earthworms. CONCLUSIONS: The present study indicates that morphology-based taxonomy of astome ciliates needs to be tested in the light of molecular and ecological data as well. The use of morphological identification alone is likely to miss species that are well delimited based on molecular markers and ecological traits and can lead to the underestimation of diversity and overestimation of host range. An integrative approach along with distinctly increased taxon sampling would be helpful to assess the consistency of the eco-evolutionary trend in astome ciliates.


Assuntos
Cilióforos/classificação , Cilióforos/isolamento & purificação , DNA Espaçador Ribossômico/genética , Trato Gastrointestinal/parasitologia , Oligoquetos/parasitologia , RNA Ribossômico 28S/genética , Animais , Cilióforos/genética , DNA Espaçador Ribossômico/análise , Ecologia , Genes de RNAr/genética , Interações Hospedeiro-Parasita/fisiologia , Oligoquetos/classificação , Oligoquetos/genética , Filogenia , RNA Ribossômico , RNA Ribossômico 28S/análise , Análise de Sequência de DNA
7.
ISME J ; 14(2): 609-622, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31719654

RESUMO

Documenting the natural diversity of eukaryotic organisms in the nonhuman primate (NHP) gut is important for understanding the evolution of the mammalian gut microbiome, its role in digestion, health and disease, and the consequences of anthropogenic change on primate biology and conservation. Despite the ecological significance of gut-associated eukaryotes, little is known about the factors that influence their assembly and diversity in mammals. In this study, we used an 18S rRNA gene fragment metabarcoding approach to assess the eukaryotic assemblage of 62 individuals representing 16 NHP species. We find that cercopithecoids, and especially the cercopithecines, have substantially higher alpha diversity than other NHP groups. Gut-associated protists and nematodes are widespread among NHPs, consistent with their ancient association with NHP hosts. However, we do not find a consistent signal of phylosymbiosis or host-species specificity. Rather, gut eukaryotes are only weakly structured by primate phylogeny with minimal signal from diet, in contrast to previous reports of NHP gut bacteria. The results of this study indicate that gut-associated eukaryotes offer different information than gut-associated bacteria and add to our understanding of the structure of the gut microbiome.


Assuntos
Biodiversidade , Microbioma Gastrointestinal , Metagenômica , Primatas/microbiologia , Primatas/parasitologia , Animais , Animais Selvagens/microbiologia , Animais Selvagens/parasitologia , Blastocisto/classificação , Cercopithecidae/microbiologia , Cercopithecidae/parasitologia , Cilióforos/classificação , Cilióforos/genética , Cilióforos/isolamento & purificação , Dieta , Endolimax/classificação , Endolimax/genética , Endolimax/isolamento & purificação , Entamoeba/classificação , Entamoeba/genética , Eucariotos/classificação , Eucariotos/genética , Eucariotos/isolamento & purificação , Fezes/microbiologia , Fezes/parasitologia , Fungos/classificação , Fungos/genética , Fungos/isolamento & purificação , Hominidae/microbiologia , Hominidae/parasitologia , Especificidade de Hospedeiro , Lemur/microbiologia , Lemur/parasitologia , Nematoides/classificação , Nematoides/genética , Nematoides/isolamento & purificação , Filogenia , Platirrinos/microbiologia , Platirrinos/parasitologia
8.
J Dairy Sci ; 103(3): 2373-2386, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31882219

RESUMO

Wheat is the most common concentrate fed to grazing dairy cows in Australia, but no studies have examined the effects of wheat proportion in a pasture-based diet on milk production and methane emissions. In this 47-d experiment, 32 Holstein dairy cows were offered 1 of 4 diets during d 1 to 36. Cows in each of the dietary treatment groups were individually offered no wheat (W0) or wheat at 3 kg of dry matter (DM)/d (W3), 6 kg of DM/d (W6), or 9 kg of DM/d (W9). The remainder of the diet was 2.2 kg of DM of concentrate mix and freshly harvested perennial ryegrass (Lolium perenne) such that all individual cows were offered a total diet of approximately 20.2 kg of DM/d. From d 37 to 47 the diets of cows receiving treatments W0 and W3 remained unchanged, but cows in treatments W6 and W9 received the W3 diet. Individual cow feed intakes, milk yields, milk compositions, and methane emissions were measured for d 31 to 35 (period 1) and d 45 to 47 (period 2). During period 1, the mean intakes of cows offered the W0, W3, W6, and W9 diets were 19.2, 20.4, 20.2, and 19.8 kg of DM/d. Diet caused differences in energy-corrected milk, and means for W0, W3, W6, and W9 were 29.5, 32.4, 33.0, and 32.9 kg/d, respectively. Milk fat percentage differed with respective means of 3.93, 3.94, 3.69, and 3.17. Diets also caused differences in methane emissions, with means for W0, W3, W6, and W9 of 440, 431, 414, and 319 g/d. During period 1, the cows fed the W9 diet produced less methane and had lower methane yields (g/kg of DMI) and intensities (g/kg of energy-corrected milk) than cows fed the W3 diet. However, in period 2 when the wheat intake of cows in the W9 treatment was reduced to the same level as in the W3 treatment, their methane emissions, yields, and intensities were similar to those offered the W3 treatment, yet protozoa numbers in ruminal fluid were still much lower than those in cows offered the W3 treatment. Our research shows that for diets based on perennial ryegrass and crushed wheat, only the diet containing more than 30% crushed wheat resulted in substantially depressed milk fat concentration and reduced methane emissions, methane yield, and methane intensity. Thus, although feeding a diet with a high proportion of wheat can cause substantial methane mitigation, it can come at the cost of depression in milk fat concentration.


Assuntos
Ração Animal , Bovinos , Dieta/veterinária , Metano/biossíntese , Leite , Rúmen/parasitologia , Triticum , Animais , Austrália , Cilióforos/isolamento & purificação , Indústria de Laticínios , Feminino , Herbivoria , Lactação , Lolium , Poaceae
9.
Parasitol Res ; 119(2): 755-758, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31811426

RESUMO

The ciliate species Balantioides coli can be cross-transmitted between humans and several animal species. Usually harmless, sometimes it can be pathogenic and cause the death of the host. In birds, B. coli has been confirmed in ostriches by genetic analysis, but the identification from South American greater rheas (Rhea americana) and lesser rheas (Rhea pennata pennata) is tentative. Since these species are reared for commercial purposes and for reintroduction into the wild, it is necessary to elucidate whether the ciliate from rheas is B. coli to minimize health risks for humans and for other domestic and wild animals. Individual parasite cells are collected from Argentinean isolates of reared greater rheas and of wild and reared lesser rheas, and their ITS region was PCR amplified; the cloning products were sequenced and compared with sequences available in public databases. The results have shown that several sequence types are expressed at the same time in the parasite cells, and all correspond to B. coli, confirming the possibility of cross-transmission of the parasite between wild and reared South American rheas and several mammal species and humans.


Assuntos
Infecções por Cilióforos/veterinária , Cilióforos/genética , Cilióforos/isolamento & purificação , Reiformes/parasitologia , Animais , Animais Selvagens , Aves , Infecções por Cilióforos/epidemiologia , Infecções por Cilióforos/parasitologia , Humanos , América do Sul/epidemiologia
10.
Rev. bras. parasitol. vet ; 28(4): 750-753, Oct.-Dec. 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1057970

RESUMO

Abstract Cryptocaryon irritans is an obligate parasitic ciliate protozoan of wild and cultured marine fish. It causes white spot disease, and infections with this pathogen can cause significant losses for aquarists and commercial marine cultures worldwide. This study reports the occurrence of C. irritans parasitizing the ornamental reef fish, yellowtail tang, Zebrasoma xanthurum. Six days after being introduced to a new environment, 11 yellowtail tangs had white spots scattered across their bodies and fins. Suspicion of infection with C. irritans was evaluated by scraping the skin to confirm clinical diagnosis. After confirmation, the yellowtail tangs were transferred to a hospital aquarium and treated with the therapeutic agent Seachem Cupramine® for 15 days. During the treatment period, the copper concentration was monitored daily. At the end of the treatment, none of the yellowtail tangs showed clinical signs of white spots on their bodies, and skin scraping confirmed the yellowtail tangs were no longer infected. Subsequently, the yellowtail tangs were released for sale.


Resumo Cryptocaryon irritans é um protozoário ciliado parasita obrigatório de peixes marinhos selvagens e cultivados. Causa a doença dos "pontos brancos". Infecções por esse patógeno pode causar perdas significativas para aquaristas e para marinocultura comercial em todo o mundo. Este estudo relata a ocorrência de C. irritans parasitando a espécie de peixe ornamental de recife Zebrasoma xanthurum. Seis dias após serem introduzidos no novo ambiente, onze peixes apresentaram pontos brancos espalhados pelo corpo e nadadeiras. Suspeitando de infecção por C. irritans foi realizado raspado de pele para confirmar o diagnóstico clínico. Após a confirmação, os peixes foram transferidos para um aquário hospital e tratados com o agente terapêutico Seachem Cupramine® por 15 dias. Durante o período de tratamento o monitoramento da concentração de cobre foi diário através da utilização de um fotômetro. Após o final do tratamento, todos os peixes já não apresentavam mais sinais clínicos de pontos brancos pelo corpo, e foram negativos no raspado de pele, sendo foram encaminhados para comercialização.


Assuntos
Animais , Perciformes/parasitologia , Infecções por Cilióforos/veterinária , Cilióforos/isolamento & purificação , Doenças dos Peixes/parasitologia , Perciformes/classificação , Cilióforos/classificação , Aquicultura
11.
Rev Bras Parasitol Vet ; 28(2): 229-237, 2019 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-31271640

RESUMO

Massive occurrence of trichodinids is frequently accompanied by serious disease in fish farms. In this study, trichodinid species from the gills and skin of Nile tilapia (Oreochromis niloticus) farmed in the central-western region of Brazil (state of Goiás) were morphologically characterized. Dried slides were prepared from the parasites and were impregnated with silver nitrate (2%). Morphometric characteristics were determined and schematic drawings of the denticles were made using photomicrographs produced from the slides. Seven species of trichodinid ectoparasites (Protozoa: Ciliophora: Trichodinidae) were found parasitizing the gills: four of the genus Trichodina Ehrenberg, 1838; one of Tripartiella Lom, 1959; one of Paratrichodina Lom, 1963; and one of Trichodinella Srámek-Husek, 1953. On the body surface, three specimens of the genus Trichodina were identified. This study presents new geographical records of trichodinids in Brazil, thus confirming that Trichodina centrostrigeata, Trichodina compacta, Trichodina heterodentata, Paratrichodina africana and Tripartiella orthodens are widely distributed worldwide. Additionally, the first record of the genus Trichodinella in Brazil is presented.


Assuntos
Ciclídeos/parasitologia , Infecções por Cilióforos/veterinária , Cilióforos/isolamento & purificação , Doenças dos Peixes/parasitologia , Oligoimenóforos/isolamento & purificação , Animais , Aquicultura , Brasil , Cilióforos/classificação , Infecções por Cilióforos/parasitologia , Pesqueiros , Oligoimenóforos/classificação
12.
Rev Bras Parasitol Vet ; 28(4): 750-753, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31215611

RESUMO

Cryptocaryon irritans is an obligate parasitic ciliate protozoan of wild and cultured marine fish. It causes white spot disease, and infections with this pathogen can cause significant losses for aquarists and commercial marine cultures worldwide. This study reports the occurrence of C. irritans parasitizing the ornamental reef fish, yellowtail tang, Zebrasoma xanthurum. Six days after being introduced to a new environment, 11 yellowtail tangs had white spots scattered across their bodies and fins. Suspicion of infection with C. irritans was evaluated by scraping the skin to confirm clinical diagnosis. After confirmation, the yellowtail tangs were transferred to a hospital aquarium and treated with the therapeutic agent Seachem Cupramine® for 15 days. During the treatment period, the copper concentration was monitored daily. At the end of the treatment, none of the yellowtail tangs showed clinical signs of white spots on their bodies, and skin scraping confirmed the yellowtail tangs were no longer infected. Subsequently, the yellowtail tangs were released for sale.


Assuntos
Infecções por Cilióforos/veterinária , Cilióforos/isolamento & purificação , Doenças dos Peixes/parasitologia , Perciformes/parasitologia , Animais , Aquicultura , Cilióforos/classificação , Perciformes/classificação
13.
J Eukaryot Microbiol ; 66(6): 966-980, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31166639

RESUMO

The deep sea has long been a mysterious and attractive habitat for protistologists. However, logistical difficulties severely limit sampling opportunities. Consequently, our knowledge of the protists in the deep sea, (arguably the largest habitat on earth), is relatively sparse. Here, we present a unique time-series concerning three different protist taxa that share only the characteristics of being relatively large, robust to sampling, and easily identifiable to species level using light microscopy: tintinnid ciliates, phaeogromid cercozoans (e.g. Challengerids) and amphisolenid dinoflagellates. We sampled a near-shore deep water site in the N.W. Mediterranean Sea at 250 m depth over a 2-yr period at approximately weekly intervals from January 2017 to December 2018. To our knowledge, no previous studies have employed sampling on a similar time scale. We found taxa that appear to be restricted to deep waters, distinct seasonal patterns of abundance in some taxa, and in others nonseasonal successional patterns. Based on data from sampling following a flash flood event, the Challengerid population appeared to respond positively to a pulse of terrigenous input. Some of the distinct mesopelagic tintinnid ciliates and amphisolinid dinoflagellates were also found in two samples from the North Atlantic mesopelagic gathered from near the Azores Islands in September 2018. We conclude that there are a variety of protist taxa endemic to the mesopelagic, that the populations are dynamic, and they may be widely distributed in the deep waters of the world ocean.


Assuntos
Cercozoários/isolamento & purificação , Cilióforos/isolamento & purificação , Dinoflagelados/isolamento & purificação , Água do Mar/parasitologia , Biodiversidade , Ecossistema , Mar Mediterrâneo , Dinâmica Populacional , Estações do Ano
14.
Rev. bras. parasitol. vet ; 28(2): 229-237, Apr.-June 2019. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1013746

RESUMO

Abstract Massive occurrence of trichodinids is frequently accompanied by serious disease in fish farms. In this study, trichodinid species from the gills and skin of Nile tilapia (Oreochromis niloticus) farmed in the central-western region of Brazil (state of Goiás) were morphologically characterized. Dried slides were prepared from the parasites and were impregnated with silver nitrate (2%). Morphometric characteristics were determined and schematic drawings of the denticles were made using photomicrographs produced from the slides. Seven species of trichodinid ectoparasites (Protozoa: Ciliophora: Trichodinidae) were found parasitizing the gills: four of the genus Trichodina Ehrenberg, 1838; one of Tripartiella Lom, 1959; one of Paratrichodina Lom, 1963; and one of Trichodinella Ṧrámek-Huṧek, 1953. On the body surface, three specimens of the genus Trichodina were identified. This study presents new geographical records of trichodinids in Brazil, thus confirming that Trichodina centrostrigeata, Trichodina compacta, Trichodina heterodentata, Paratrichodina africana and Tripartiella orthodens are widely distributed worldwide. Additionally, the first record of the genus Trichodinella in Brazil is presented.


Resumo O parasitismo intenso por tricodinídeos está frequentemente relacionado à doença grave em fazendas de peixes. Neste estudo, espécies de tricodinídeos das brânquias e da pele de tilápias do Nilo (Oreochromis niloticus) cultivadas na região centro-oeste do Brasil (estado de Goiás) foram caracterizadas morfologicamente. As lâminas secas foram preparadas a partir dos parasitas e impregnadas com nitrato de prata (2%). As características morfométricas foram determinadas e desenhos esquemáticos dos dentículos foram confeccionados com fotomicrografias produzidas a partir das lâminas. Sete espécies de ectoparasitos tricodinídeos (Protozoa: Ciliophora: Trichodinidae) foram encontradas parasitando as brânquias: quatro do gênero Trichodina Ehrenberg, 1838; um de Tripartiella Lom, 1959; um de Paratrichodina Lom, 1963; e um de Trichodinella Ṧrámek-Huṧek, 1953. Na superfície do corpo, três espécimes do gênero Trichodina foram identificados. Este estudo apresenta novos registros geográficos de tricodinídeos no Brasil, confirmando que Trichodina centrostrigeata, Trichodina compacta, Trichodina heterodentata, Paratrichodina africana e Tripartiella orthodens estão amplamente distribuídas mundialmente. Adicionalmente, é apresentado o primeiro registro do gênero Trichodinella no Brasil.


Assuntos
Animais , Oligoimenóforos/isolamento & purificação , Infecções por Cilióforos/veterinária , Cilióforos/isolamento & purificação , Ciclídeos/parasitologia , Doenças dos Peixes/parasitologia , Brasil , Oligoimenóforos/classificação , Infecções por Cilióforos/parasitologia , Cilióforos/classificação , Aquicultura , Pesqueiros
15.
J Eukaryot Microbiol ; 66(5): 802-820, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30861256

RESUMO

Tintinnid ciliates have traditionally been described and classified exclusively based on their lorica features. Although information on the cell characters is urgently needed for a natural classification, more molecular than cytological data has been accumulated over recent years. Apparently, the tintinnids developed in the marine environment and entered freshwater several times independently. Typical freshwater tintinnids belong to the genera Tintinnidium and Membranicola. The species are comparatively well-known regarding their morphology and characterised by two unusual de novo originating ciliary rows, the ventral organelles. In contrast, the cell features in the marine/brackish Tintinnidium species, specifically their somatic ciliary patterns, are insufficiently known or not known at all. Therefore, the morphology of a common marine/brackish representative, Tintinnidium mucicola, is redescribed based on live observation and protargol-stained material. Furthermore, biogeographical and autecological data of the species are compiled from literature and own records. The phylogenetic relationships of T. mucicola are inferred and the diversity of the family Tintinnidiidae is assessed from 18S rDNA sequences. The study shows that T. mucicola is not only molecularly distinct, but also characterised by many plesiomorphic features, for instance, it does not possess a verifiable homologue to the ventral organelles. Hence, a new genus, Antetintinnidium nov. gen., is established for T. mucicola. The new insights into the diversity of Tintinnidiidae shed light on the early evolution of tintinnids and might provide clues on their adaptions to freshwater.


Assuntos
Cilióforos/isolamento & purificação , Cilióforos/classificação , Cilióforos/genética , DNA de Protozoário/genética , DNA Ribossômico/genética , Água Doce/parasitologia , Filogenia , RNA Ribossômico 18S/genética , Água do Mar/parasitologia
16.
J Eukaryot Microbiol ; 66(5): 740-751, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30746815

RESUMO

Two new soil oxytrichids, Australocirrus rubrus n. sp. and Notohymena gangwonensis n. sp., were discovered from South Korea. Morphologically, A. rubrus shares many features with A. australis, and these two species form a single clade in a molecular tree based on nuclear small subunit ribosomal RNA (SSU rRNA) gene sequences. Australocirrus rubrus mainly differs from A. australis in the color (citrine color vs. reddish) and distribution of the cortical granules. Additionally, we confirm that the genus Australocirrus is not a monophyletic group, as A. shii is separated from the clade comprising the other Australocirrus species, being clustered instead with other taxa. Notohymena gangwonensis n. sp. mainly differs from its congeners by the following combination of features: irregularly distributed cortical granules (vs. arranged in groups associated with cirri and dorsal kineties), variable four or five (usually four) transverse cirri (vs. invariable five), and the anteriormost pretransverse cirrus V/2 on 13.2-16.1% of cell length (vs. on or above 18.9% of cell length). Currently, there are no available gene sequences for members of the genus Notohymena, thus we provide SSU rRNA gene sequences from the new species of Notohymena, as well as detailed morphological descriptions of the novel species.


Assuntos
Cilióforos/crescimento & desenvolvimento , Cilióforos/isolamento & purificação , Filogenia , Cilióforos/classificação , Cilióforos/genética , DNA de Protozoário/genética , RNA Ribossômico 18S/genética , República da Coreia , Solo/parasitologia
17.
Animal ; 13(10): 2242-2251, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30786945

RESUMO

Eight ruminally-fistulated wethers were used to examine the temporal effects of afternoon (PM; 1600h) v. morning (AM; 0800 h) allocation of fresh spring herbage from a perennial ryegrass (Lolium perenne L.)-based pasture on fermentation and microbial community dynamics. Herbage chemical composition was minimally affected by time of allocation, but daily mean ammonia concentrations were greater for the PM group. The 24-h pattern of ruminal fermentation (i.e. time of sampling relative to time of allocation), however, varied considerably for all fermentation variables (P⩽0.001). Most notably amongst ruminal fermentation characteristics, ammonia concentrations showed a substantial temporal variation; concentrations of ammonia were 1.7-, 2.0- and 2.2-fold greater in rumens of PM wethers at 4, 6 and 8h after allocation, respectively, compared with AM wethers. The relative abundances of archaeal and ciliate protozoal taxa were similar across allocation groups. In contrast, the relative abundances of members of the rumen bacterial community, like Prevotella 1 (P=0.04), Bacteroidales RF16 group (P=0.005) and Fibrobacter spp. (P=0.008) were greater for the AM group, whereas the relative abundance of Kandleria spp. was greater (P=0.04) for the PM group. Of these taxa, only Prevotella 1 (P=0.04) and Kandleria (P<0.001) showed a significant interaction between time of allocation and time of sampling relative to feed allocation. Relative abundances of Prevotella 1 were greater at 2h (P=0.05), 4h (P=0.003) and 6h (P=0.01) after AM allocation of new herbage, whereas relative abundances of Kandleria were greater at 2h (P=0.003) and 4h (P<0.001) after PM allocation. The early post-allocation rise in ammonia concentrations in PM rumens occurred simultaneously with sharp increases in the relative abundance of Kandleria spp. and with a decline in the relative abundance of Prevotella. All measures of fermentation and most microbial community composition data showed highly dynamic changes in concentrations and genus abundances, respectively, with substantial temporal changes occurring within the first 8h of allocating a new strip of herbage. The dynamic changes in the relative abundances of certain bacterial groups, in synchrony with a substantial diurnal variation in ammonia concentrations, has potential effects on the efficiency by which N is utilised by the grazing ruminant.


Assuntos
Amônia/metabolismo , Archaea/isolamento & purificação , Bactérias/isolamento & purificação , Lolium , Microbiota , Nitrogênio/metabolismo , Ovinos/microbiologia , Ração Animal/análise , Animais , Cilióforos/isolamento & purificação , Dieta/veterinária , Fermentação , Pradaria , Masculino , Nova Zelândia , Rúmen/microbiologia
18.
J Eukaryot Microbiol ; 66(5): 694-706, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-30657224

RESUMO

A new hypotrichous ciliate, Schmidtiella ultrahalophila gen. nov., spec. nov., was isolated from a solar saltern on the island of Sal, Cape Verde. The possession of only one short dorsal kinety clearly distinguishes S. ultrahalophila from other known hypotrichous genera and species. Further diagnostic characters include: a flexible and slender body, an average size of 85 × 15 µm in vivo; a bipartite adoral zone with two hypertrophied frontal adoral membranelles and nine to twelve ventral adoral membranelles; three frontal, one parabuccal, two frontoventral, two or three postoral ventral, and two or three frontoterminal cirri; and marginal cirral rows variable in number, usually one on each side. Ontogenetic data indicate the following: the frontal-ventral cirri originate from six or five anlagen; the proter inherits the parental adoral zone; the frontal and ventral cirri originate from five or six anlagen; and the marginal cirral rows and the dorsal kinety tend to originate intrakinetally. Additional marginal rows are rarely derived from de novo anlagen. Based on its morphology, morphogenesis and its SSU rRNA phylogenetic placement, the new species should be assigned to the order Sporadotrichida Fauré-Fremiet, 1961. Due to low taxon sampling, however, its exact position in this order remains enigmatic.


Assuntos
Cilióforos/crescimento & desenvolvimento , Cilióforos/isolamento & purificação , Filogenia , Cabo Verde , Cilióforos/classificação , Cilióforos/genética , Ilhas , Morfogênese
19.
Microb Ecol ; 77(2): 317-331, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30051173

RESUMO

One decisive factor controlling the distribution of organisms in their natural habitats is the cellular response to environmental factors. Compared to prokaryotes, our knowledge about salt adaptation strategies of microbial eukaryotes is very limited. We, here, used a recently introduced approach (implementing proton nuclear magnetic resonance spectroscopy) to investigate the presence of compatible solutes in halophilic, heterotrophic ciliates. Therefore, we isolated four ciliates from solar salterns, which were identified as Cyclidium glaucoma, Euplotes sp., Fabrea salina, and Pseudocohnilembus persalinus based on their 18S rRNA gene signatures and electron microscopy. The results of 1H-NMR spectroscopy revealed that all four ciliates employ the "low-salt-in" strategy by accumulating glycine betaine and ectoine as main osmoprotectants. We recorded a linear increase of these compatible solutes with increasing salinity of the external medium. Ectoine in particular stands out as its use as compatible solute was thought to be exclusive to prokaryotes. However, our findings and those recently made on two other heterotroph species call for a re-evaluation of this notion. The observation of varying relative proportions of compatible solutes within the four ciliates points to slight differences in haloadaptive strategies by regulatory action of the ciliates. Based on this finding, we provide an explanatory hypothesis for the distribution of protistan diversity along salinity gradients.


Assuntos
Diamino Aminoácidos/metabolismo , Betaína/metabolismo , Cilióforos/metabolismo , Cloreto de Sódio/metabolismo , Cilióforos/genética , Cilióforos/isolamento & purificação , Cilióforos/ultraestrutura , Processos Heterotróficos , Microscopia Eletroquímica de Varredura , Pressão Osmótica , Tanques/química , Tanques/microbiologia , Salinidade
20.
J Wildl Dis ; 55(2): 375-386, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30289337

RESUMO

During March to August of 2017, hundreds of leopard sharks ( Triakis semifasciata) stranded and died on the shores of San Francisco Bay, California, US. Similar mass stranding events occurred in 1967 and 2011, but analysis of those epizootics was incomplete, and no etiology was confirmed. Our investigation of the 2017 epizootic revealed severe meningoencephalitis in stranded sharks, raising suspicion for infection. We pursued a strategy for unbiased pathogen detection using metagenomic next-generation sequencing followed by orthogonal validation and further screening. We showed that the ciliated protozoan pathogen, Miamiensis avidus, was present in the central nervous system of leopard ( n=12) and other shark species ( n=2) that stranded in San Francisco Bay but was absent in leopard sharks caught elsewhere. This ciliated protozoan has been implicated in devastating outbreaks in teleost marine fish but not in wild elasmobranchs. Our results highlight the benefits of adopting unbiased metagenomic sequencing in the study of wildlife health and disease.


Assuntos
Baías , Infecções por Cilióforos/veterinária , Cilióforos/isolamento & purificação , Doenças dos Peixes/parasitologia , Técnicas de Amplificação de Ácido Nucleico , Tubarões/parasitologia , Animais , Cilióforos/genética , Infecções por Cilióforos/epidemiologia , Infecções por Cilióforos/parasitologia , Doenças dos Peixes/epidemiologia , Metagenômica , São Francisco/epidemiologia
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