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2. A new myxozoan parasite, Myxobolus allami sp. n. (Myxozoa: Myxobolidae) from the intestinal wall of Sparidentex hasta (Valenciennes) in Arabian Gulf
- Creator:
- Mansour, Lamjed, Abdel-Haleem, Heba M., Atwa, Marwa, Darwish, Ahmed B., Al-Quraishy, Saleh, and Abdel-Baki, Abdel-Azeem S.
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- Myxosporea, ultrastructure, phylogeny, SSU rDNA, and Saudi Arabia
- Language:
- English
- Description:
- Myxobolus allami sp. n. is described from the intestinal wall of the silvery black porgy, Sparidentex hasta (Valenciennes), off Saudi Arabian coast of Arabian Gulf. Two of 20 examined fish were found to be infected with irregular-shaped plasmodia 3-8 mm long × 2-3 mm wide. Mature myxospores are subspherical to elliptical in the valvular view and oval in the sutural view, and are 11-13 (12) µm long, 7-8 (7.5) µm wide and 10-12 (10.8) µm thick. Spores have relatively thin valves and mostly (~ 72%) end with short caudal appendages of ~3 µm long. The spores also have two polar capsules, which are oval to elliptical and measure 5-7 (5.7) µm in length and 2-3 (2.7) µm in width. Polar filaments are coiled, with three turns. Transmission electron microscopy revealed that caudal appendages originated from the sutural edge at the posterior pole of the myxospore with density similar to that of its valves. The SSU rRNAgene sequence of the present species does not match any available sequences in GenBank. Phylogenetically, this species is sister to Myxobolus khaliji Zhang, Al-Qurausihy et Abdel-Baki, 2014 within a well-supported clade of Myxobolus-Henneguya with species infecting marine fishes. The combination of molecular data and morphological differences between this and other species of Myxobolus Bütschli, 1882 lead us to propose that the present form be established as a new species, M. allami. The present study also provides more evidence for the idea that caudal appendages cannot be reliably used to distinguish the species of the genera Myxobolus and Henneguya Thélohan, 1892.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. Ceratomyxa bohari sp. n. (Myxozoa: Ceratomyxidae) from the gall bladder of Lutjanus bohar Forsskål from the Red Sea coast off Saudi Arabia: morphology, seasonality and SSU rDNA sequence
- Creator:
- Mansour, Lamjed, Abdel-Baki, Abdel-Azeem S, Tamihi, Ahmad F, and Al-Quraishy, Saleh
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- parazitické organismy, spóry, fylogeneze, parasitic organisms, spores, phylogeny, Myxosporea, fish parasites, Bivalvulida, coelozoic infection, Lutjanidae, 2, and 59
- Language:
- English
- Description:
- A new myxozoan, Ceratomyxa bohari sp. n., infecting the gall bladder of two-spot red snapper, Lutjanus bohar Forsskål, in the Red Sea off Saudi Arabia, is described using light microscopy and characterised genetically. The infection was recorded as mature spores floating free in the bile. The overall prevalence of infection of the type host was 19% (67 fish infected of 360 examined), with the highest prevalence in autumn (31%; 28/90) and the lowest in winter at 12% (11/90). Mature spores are slender and slightly crescent-shaped in the frontal view, with anterior and posterior margins tapered gradually to rounded valvular tips. Spore valves are unequal with a prominent sutural line. The spore dimensions are 3-4 μm (mean 3.5 μm) in length and 16-19 μm (mean 17 μm) in thickness. Two polar capsules are spherical, equal in size, 1.5 μm in diameter. Coils of the polar filament are indiscernible. The sporoplasm is binucleated and fills nearly one third of the extracapsular space restricted to the area below the capsules. The molecular analysis based on the small subunit rDNA (SSU rDNA) sequence revealed a close relationship with majority of species of Ceratomyxa Thélohan, 1892 and phylogenetic clustering with species from different geographical location. Thus, the shorter spore of the present Ceratomyxa species and the divergence of the SSU rDNA sequences were the distinctive features that separate it from all previously described species and identified this parasite as a new species of Ceratomyxa., Lamjed Mansour, Abdel-Azeem S. Abdel-Baki, Ahmad F. Tamihi, Saleh Al-Quraishy., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
4. Ceratomyxa drepanopsettae in the gallbladder of Atlantic halibut, Hippoglossus hippoglossus, from the northwest Atlantic Ocean
- Creator:
- Morrison, Carol M., Martell, D. John, Leggiadro, Cynthia, and O´Neil, David
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Atlantic halibut, Hippoglossus hippoglossus, Myxosporea, Ceratomyxa drepanopsettae, trophozoites, sporoblast, sporogenesis, and spore
- Language:
- English
- Description:
- Trophozoites of Ceratomyxa drepanopsettae Averintsev, 1907 (Myxosporea: Ceratomyxidae) containing prominent refractile granules were found in the gallbladders of all but one of eight halibut, the exception being a single juvenile. They ranged in shape and size from globular forms 5-10 pm in diameter, to rounded structures with pseudopodia and one or more processes that were up to 500 pm in length and packed with refractile granules. Some trophozoites were free in the bile, while others were attached to the epithelium of the gallbladder wall by pseudopodia which extended between the microvilli. Many free trophozoites were attached to each other by septate junctions between their pseudopodia. There were small cylindrical papillae on the surface of the trophozoites, and the rounded portions contained two vegetative nuclei, generative cells (some attached by junctions) and, in many cases, feeding vacuoles. During sporogony, a binucleate sporoplasmic cell and the capsulogenic cells of some sporoblasts were engulfed by valvogenic cells before they began to differentiate; whereas other sporoblasts consisted of six cells attached to each other, two being capsulogenic cells containing external tubes, two sporoplasmic cells and two valvogenic cells. There was a septate junction around the opening of the rounded polar capsule of the spore, between the capsulogenic and valvogenic cell. Sporoplasmosomes appeared to form in smooth membraned vesicles, possibly part of the Golgi apparatus. Spores had a thin, delicate membrane, and elongate shell-valves, most of which were asymmetric, and bent or folded. A sporo-plasm extended on either side of the distinct, straight suture line, but did not penetrate into the valves.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. Characterisation of sphaeractinomyxon types (Cnidaria: Myxozoa) from marine and freshwater oligochaetes in a Portuguese estuary, with the demise of the endocapsa collective group
- Creator:
- Rocha, Sónia, Alves, Ängela, Antunes, Carlos, Fernandes, Pedro, Azevedo, Carlos, and Casal, Graça
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- kroužkovci, Annelida, Minho (Španělsko a Portugalsko : řeka), Minho River (Spain and Portugal), Myxosporea, actinospore, life cycle, SSU rRNA gene, 2, and 59
- Language:
- English
- Description:
- Six types of sphaeractinomyxon are reported from the coelomic cavity of oligochaetes collected from the Minho River estuary in northern Portugal. Four new types are morphologically and molecularly described from freshwater species belonging to the genera Psammoryctides Hrabě and Potamothrix Vejdovský et Mrázek in the upper estuary, thus significantly increasing the number of known freshwater sphaeractinomyxon. In the lower estuary, sphaeractinomyxon types 8 and 10 of Rangel et al. (2016) are recorded infecting the marine oligochaete Tubificoides pseudogaster (Dahl). A single specimen of T. pseudogaster further displayed infection by one of the four new types found in the upper estuary, suggesting the involvement of sphaeractinomyxon in the life cycles of myxosporean species that infect migratory fish hosts. The acquisition of these second hosts is proposed to have allowed the myxosporean counterparts of sphaeractinomyxon to cross environmental barriers and conquer new habitats. Phylogenetic analyses of the SSU rRNA gene reveal the four new types clustering within the monophyletic clade of mugiliform-infecting myxobolids, strengthening the previously proposed involvement of the sphaeractinomyxon collective group in the life cycles of this specific group of myxosporeans. Endocapsa types also cluster within the latter clade, having actinospores that differ from those of sphaeractinomyxon only in the presence of valvular swellings that do not change when in contact with water. In this study, however, one type was found displaying actinospores with and without valvular swellings in the same oligochaete specimen. This overlap in actinospore morphology is given as grounds for the demise of the endocapsa collective group., Sónia Rocha, Ängela Alves, Carlos Antunes, Pedro Fernandes, Carlos Azevedo and Graça Casal., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
6. Experimental infection model with the bivalvulid Enteromyxum leei (Myxidiidae) in the sharpsnout seabream, Diplodus puntazzo (Sparidae), and evaluation of the antiparasitic efficacy of a functional diet
- Creator:
- Henry, Morgane A., Kokou, Fotini, Palenzuela, Oswaldo, Pyrenis, George, and Rigos, George
- Format:
- počítač and online zdroj
- Type:
- model:article and TEXT
- Subject:
- cohabitation parasitical challenge, Myxosporea, immune response, hemoglobin, inflammation, gut parasite, parasite intensity, parasite prevalence, and qPCR
- Language:
- English
- Description:
- An infection model for sharpsnout seabream Diplodus puntazzo (Walbaum) challenged with the myxosporean Enteromyxum leei (Diamant, Lom et Dyková, 1994), resembling the natural infection conditions, was used to evaluate the antiparasitic efficacy of a functional diet. Fish of an average weight of 12.5 ± 1.2 g were delivered either a functional (included as feed supplement at 0.3% levels) or a control extruded diet. After four weeks of administration of the experimental diets, fish were challenged with the parasites (cohabitation with infected donors; donor: recipient ratio 1 : 1). The experiment was terminated four weeks after the start of the challenge. At the end of the experiment, growth and feeding (specific growth rate and feed efficiency), as well as immunological parameters (respiratory burst activity, antibacterial activities, hemoglobin concentration, anti-protease activity and ceruloplasmin activity) were measured along with cumulative mortality and total parasitic count in the gut. No significant difference was evident with regard to growth and feeding performance, mortality, gut parasitic load or immunological parameters as the parasitical challenge significantly affected both the performance of the control and functional diet fed fish. However, there was a less prominent impact on antibacterial, anti-protease and ceruloplasmin activity in fish fed with the functional diet. Overall, the present study validated the experimental cohabitation infection model and evaluated the efficacy of a functional ingredient as an antiparasitic agent, showing some potential effects on the fish immune response.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
7. Henneguya cynoscioni sp. n. (Myxosporea: Bivalvulida), an agent of severe cardiac lesions in the spotted seatrout, Cynoscion nebulosus (Teleostei: Sciaenidae)
- Creator:
- Dyková, Iva, Buron, Isaure de, Roumillat, William A., and Fiala, Ivan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Henneguya cynoscioni, Myxosporea, pathogenicity, cardiac henneguyosis, Cynoscion nebulosus, Cardicola laruei, and Atlantic Ocean
- Language:
- English
- Description:
- A new myxosporean species, Henneguya cynoscioni sp. n., is described from the spotted seatrout, Cynoscion nebulosus (Cuvier) (Sciaenidae) as a causative agent of cardiac henneguyosis. This new myxosporean species is characterized by the morphology of spores and the sequence of SSU rDNA. Examination of 227 spotted seatrout from four South Carolina estuaries in 2008-2010 revealed a 33.5% total prevalence of H. cynoscioni. Henneguya cynoscioni produces lesions in the bulbus arteriosus, its specific site of infection. The severity of lesions and their impact on the bulbus arteriosus is proportional to the number of plasmodial stages developing in this segment of the heart, being most pronounced in host reaction directed against spores liberated from plasmodia.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8. Infection in the fins of the goldfish Carassius auratus caused by Myxobolus diversus (Myxosporea)
- Creator:
- Molnár, Kálmán and Székely, Csaba
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Myxosporea, Myxobolus diversus, goldfish, fins, and histopathology
- Language:
- English
- Description:
- During health surveys of 7- to 9-week-old goldfish (Carassius auratus L.) fingerlings in a fish farm near Budapest, Hungary, myxosporean plasmodia were observed on the fins. Plasmodia were most frequently found at the intersegmental joints of the finrays. Spores of Myxobolus diversus Nie et Li, 1973 known from China, were detectable in the mature plasmodia located within the lumen, and less often on the surface, of the cartilaginous finrays. The external wall of the plasmodia was constituted by a capsule formed from a collagenous material identical with the cartilaginous substance of the finrays. Matured plasmodia were filled by spores of 12-14 × 8-9.5 µm in size. The relatively small plasmodia caused only small deformities on the fins. Their importance is, however, not negligible, as in an ornamental fish such as the goldfish even a minor damage of the fins causes a loss of value. Besides a report on the first European occurrence and pathological aspects, a redescription of this parasite of Far-Eastern origin is given.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9. Infections of Unicauda clavicauda (Kudo, 1934) (Myxozoa) in the skin of Notropis hudsonius (Cyprinidae) from Montana, with a synopsis of the genus Unicauda Davis, 1944
- Creator:
- Cone, David K. and Melendy, Jason S.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Myxosporea, Unicauda clavicauda, and Notropis hudsonius
- Language:
- English
- Description:
- Infections of Unicauda clavicauda (Kudo, 1920) Davis, 1944 (Myxozoa) are described from Notropis hudsonius (Clinton) in Montana. Plasmodia form beneath scales of the body and produced spores within a loosely-defined matrix. Fixed spores are oval in front view, 11-14 pm long and 9-10.5 pm wide, and contain a posterior appendage that is up to 26 pm long. The polar capsules are 4-6 pm long and 2.5-4 pm wide. The study represents the first report of U. clavicauda since the original species description and a new host and geographical record. The taxonomic history of Unicauda Davis, 1944 is summarised and it is concluded the following 10 species are valid members of the genus: U. aristichthydis Zhao et Ma, 1995, U. brachyura (Ward, 1919), U. caudatus (Gogebashvili, 1965), U clavicauda, U. crassicauda (Kudo, 1934), U. lumae Rahemo, 1976, U. macrura (Gurley, 1893), U. magna Minchew, 1981, U. pelteobagrus Ma, 1998, and U. wuhanensis Xiao et Chen, 1993. All of these species have circular, subcircular, or oval spores in frontal view and all parasitise fish of the superorder Ostariophysi. As a group they are known from temperate freshwater locations in North America, Europe and Asia. A list of 16 species described or transferred to Unicauda at one time or another, but not recognised as members of the genus in the present study, is provided.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
10. Kudoa dianae sp. n. (Myxosporea: Multivalvulida), a new parasite of bullseye puffer, Sphoeroides annulatus (Tetraodontiformes: Tetraodontidae)
- Creator:
- Dyková, Iva, Fajer Avila, Emma Josefina, and Fiala, Ivan
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- Myxosporea, Multivalvulida, taxonomy, and SSU rDNA
- Language:
- English
- Description:
- A new multivalvulid myxosporean species, Kudoa dianae sp. n., is described from bullseye puffer, Sphoeroides annulatus (Jenyns) (Tetraodontiformes: Tetraodontidae). Plasmodia develop in extramuscular sites, in the wall of oesophagus and less frequently on mesenteries. Mature spores can reach lumen of the digestive tract directly by disruption of plasmodial wall or via macrophage transport to the oesophageal epithelium. New species is characterised by morphology of spores and by the complete sequence of SSU rRNA gene that differs from all hitherto known sequences of Kudoa species. Spore morphology (moderate-sized, simple non-ornate spores, quadrate in apical view) clusters with that of Kudoa scienae, K. cerebralis, K. chilkaensis, K. leiostomi, K. funduli, K. cascasia and K. ovivora. Analysis of phylogenetic relationships (using SSU rRNA gene sequences) among five Kudoa species, the molecular data of which are available thus far, revealed that K. dianae is distinguishable from these five species and that its closest relation is with K. miniauriculata.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
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