Csaba Székely

Csaba Székely
Veterinary Medical Research Institute

PhD, habil

About

220
Publications
52,102
Reads
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3,576
Citations
Citations since 2016
57 Research Items
1330 Citations
2016201720182019202020212022050100150200
2016201720182019202020212022050100150200
2016201720182019202020212022050100150200
2016201720182019202020212022050100150200
Additional affiliations
February 2013 - February 2013
Universiti Malaysia Terengganu
Position
  • Myxozoans
October 2010 - November 2010
Universiti Malaysia Terengganu
Position
  • Myxozoans
January 2008 - May 2020
University of Porto
Position
  • collaborator

Publications

Publications (220)
Article
Full-text available
Recently a new group of circoviruses have been detected in tissues of Barbel fish and European catfish in Hungary. In our study circovirus genomes were screened in eight additional fish species for the detection and characterization of circoviruses. Two species of these bore circoviral sequences based on conventional PCR assay targeting the replica...
Article
Full-text available
The preparation of myxosporeans for the description of myxospores and their preservation as type material in parasitological collections show great variations. Most frequently, formalin and ethanol are used for fixation and Giemsa solution for staining spores. In this work, authors studied the effect of 80% ethanol and 10% formalin fixation, freezi...
Article
Full-text available
During surveys on myxosporean parasites of Lake Balaton and River Danube fishes, two Thelohanellus spp. were found on tench (Tinca tinca) and on common nase (Chondrostoma nasus). They were identified as Thelohanellus pyriformis and Thelohanellus cf. fuhrmanni, respectively. Myxospores of T. pyriformis from tench were collected from arteria branchia...
Article
Dermocystidiosis in common carp (Cyprinus carpio L.) as a skin infection in the form of small, pea‐sized bulging nodules is well‐known in Hungary. Its occurrence is sporadic, and the pathogenic effect is generally moderate. Nonetheless, here we report an unusual case of the infection when a mass of dermocystid spore‐filled hyphae‐like cysts formed...
Book
Full-text available
ПРАКТИЧЕСКОЕ РУКОВОДСТВО ПО ЗАБОЛЕВАНИЯМ ТЕПЛОВОДНЫХ РЫБ В ЦЕНТРАЛЬНОЙ И ВОСТОЧНОЙ ЕВРОПЕ, НА КАВКАЗЕ И В ЦЕНТРАЛЬНОЙ АЗИИ
Article
Full-text available
In aquaculture, disease management and pathogen control are key for a successful fish farming industry. In past years, European catfish farming has been flourishing. However, devastating fish pathogens including limiting fish viruses are considered a big threat to further expanding of the industry. Even though mainly the ranavirus (Iridoviridea) an...
Article
Full-text available
Myxosporean infection of Indian major carps (rohu, Labeo rohita; catla, Gibelion catla; mrigal, Cirrhinus mrigala) was examined from two fish farms and two fish markets in West Bengal, India. One Thelohanellus and four Myxobolus species were detected from the fins and scales of the investigated species. Comprehensive morphological and molecular bio...
Article
Full-text available
In 2016, an intense copepod infection was recorded from a reservoir in proximity to the Danube River in Hungary from visibly emaciated wels catfish, Silurus glanis. The parasite-induced pathology was described but parasite identity was not conclusive. Additional sample collections in 2017 and 2018 allowed for identification using both light and sca...
Article
Full-text available
The American pumpkinseed Lepomis gibbosus, was introduced to Europe more than one hundred years ago. Currently it is a common fish in European freshwaters but relatively few specific parasites infect this fish in this new habitat. In Europe only a single species, Myxobolus dechtiari seems to represent the American myxosporean fauna of centrarchid f...
Article
Full-text available
Thelohanellus nikolskii, Achmerov, 1955 is a well-known myxozoan parasite of the common carp (Cyprinus carpio L.). Infection regularly manifests in numerous macroscopic cysts on the fins of two to three month-old pond-cultured carp fingerlings in July and August. However, a Thelohanellus infection is also common on the scales of two to three year-o...
Article
In this study, we provide the first genetically verified distribution record beyond its native range of Ligula pavlovskii, a high-impact endoparasite of Ponto-Caspian gobies. According to parasitological surveys, ligulosis was detected for the first time in monkey goby individuals collected from Lake Balaton in 2004, 34 years after the first record...
Article
Full-text available
Occurrence of metacercariae of potentially zoonotic trematodes (Platyhelminthes: Digenea) in the musculature of common carp (Cyprinus carpio L. 1758) was monitored in four Hungarian aquacultures. Four geographically distinct fish farms (located in the Northwestern, Southwestern, Northeastern and Southeastern parts of Hungary) were selected for the...
Article
The abundance of mycoplasma-like microorganisms seems to be common in the intestinal tract of fish, but their occurrence in other organs can be considered pathological. Isolation of piscine mycoplasmas is essential to prove their virulence. In this study a total of 100 specimens of nine freshwater fish species collected from natural waters and fish...
Article
Full-text available
This study was a cooperative investigation of myxosporean infections of Notopterus notopterus, the bronze featherback, which is a popular food fish in the South Asian region. We examined fish from Lake Kenyir, Malaysia and the River Ganga, Hastinapur, Uttar Pradesh, India, and observed infections with two myxosporeans: Myxidium cf. notopterum (Myxi...
Article
Full-text available
The Carpathian brook lamprey (Eudontomyzon danfordi Regan, 1911) is an endemic protected species of Cephalaspidomorphi in the Carpathian Basin. No parasites have become known from these jawless vertebrates to date. Here, the authors describe an infection from a single specimen manifesting in protuberant skin cysts 7-10 mm in diameter, scattered on...
Article
Full-text available
Two species of the genus Posthodiplostomum (Digenea: Diplostomatidae) ( Posthodiplostomum brevicaudatum Nordmann, 1832 and Posthodiplostomum cuticola Nordmann, 1832) are known as parasites of Hungarian native fishes. Metacercariae of P. cuticola are widespread in Europe and cause black spot disease. Several species of Posthodiplostomum were describ...
Article
Full-text available
Two adult barbels ( Barbus barbus ) with visible skin tumours were subjected to histopathological and molecular examinations. The fish were caught in the River Danube near Budapest. Papillomas were found around their oral cavity, at the operculum and at the pectoral fins, while epidermal hyperplasias were seen on the body surface. Cyprinid herpesvi...
Preprint
Full-text available
Common carp is the third most cultivated freshwater species in the world. Carp aquaculture is usually performed in a semi-intensive manner, in earthen ponds, where parasitic diseases can easily compromise fish health, especially in the hot summer months, leading to production and economic losses. This guide provides useful information about the bio...
Article
Metacercariae of various species within the genus Holostephanus Szidat, 1936 (Trematoda: Digenea: Cyathocotylidae) occur in muscles of both farmed and wild fish, including common carp ( Cyprinus carpio Linnaeus, 1758). The life cycle includes a snail as first intermediate host, fish as second intermediate host and birds or mammals as final hosts. W...
Article
Flavobacterial infections are among the causes of fish losses in farms with the emergence of antibiotic-resistant isolates. Silver nanoparticles (AgNPs) are known for their potent antimicrobial activity against differnet types of bacteria. In this study, we evaluated the antibacterial properties of AgNPs (diameter = 23 nm) against Flavobacterium jo...
Article
Full-text available
Examination of 35 barramundi (Lates calcarifer) from aquaculture cages in Setiu Wetland, Malaysia, revealed a single fish infected with three Henneguya spp. (Cnidaria: Myxosporea). Characterization of the infections using tissue tropism, myxospore morphology and morphometry, and 18S rDNA sequencing, supported description of three new species: Henne...
Article
Full-text available
The main fish host reaction to an infection with third stage anisakid nematode larvae is a response in which host immune cells (macrophages, granulocytes, lymphocytes) in affected internal organs initially are attracted to the parasite whereafter fibroblasts may enclose the parasite forming granuloma. Generally, the reaction is non-lethal to the pa...
Presentation
Full-text available
Introduction: During an extensive carp monitoring for zoonotic trematodes in Hungary (ParaFishControl project) one of the aquacultures was heavily infected by muscle metacercariae. Morphological and molecular analyses were carried out for taxonomical identification. The evaluation of the food safety required to determine the viability and zoonotic...
Poster
Introduction: Posthodiplostomum (Digenea: Diplostomidae) species are well-known for a long time from native freshwater fishes in Hungary (Molnár, 1969). P. cuticola Nordmann, 1832 is an important pathogen of cyprinid fishes as the causative agent of the black spot disease. The encysted metacercariae often occur in the scales, skin, fins and skeleto...
Book
Full-text available
Due to the recent rapid development of freshwater aquaculture in the Caucasus Region, many new and previously known fish diseases have appeared. One of the most prominent features of the region’s aquaculture is that it is mostly based on the rearing of cyprinids, mainly the common carp (Cyprinus carpio), as well as a few other predatory fish specie...
Article
Introduction Myxozoan infections of Indian freshwater fishes are relatively well studied, but their validity is supported with molecular and phylogenetic data only for a few species. Objectives The primary objective was to present molecular data for two Myxozoan species, Myxobolus cylindricus and Henneguya gachua collected from Indian freshwater f...
Article
Full-text available
At this time the occurrence of three Carassius taxa (C. carassius, C. auratus auratus and C. auratus gibelio) are known from Europe. Crucian carp [Carassius carassius (Linnaeus, 1758)] is a native fish species in European waters. The goldfish, a species of Chinese origin arrived to Europe long time ago, and at the time when Linnaeus in 1758 publis...
Article
Full-text available
A new Henneguya species, H. jaczoi sp. n., is described from perch (Perca fluviatilis) from Lake Balaton, Hungary. This species infects the palatal region of the fish, forming large plasmodia in the thickened caudal part of the buccal cavity and at the dorsal ends of the cartilaginous gill arches. The species differs from the gill-dwelling Henneguy...
Article
Full-text available
In a parasitological survey of freshwater fishes near Meerut, Uttar Pradesh, India, myxozoan infections in Pabdah catfish Ompok pabda Ham. (Siluriformes: Siluridae) were found. Round plasmodia and scattered spores of Myxobolus ompok n. sp. were found in the kidney of the host. Plasmodia measuring 150–200 μm were located in the renal interstitium. S...
Poster
Metagonimus Katsurada, 1912 (Digenea: Heterophyidae) species are well-known zoonotic parasites, which reach their mature stage in the small intestine of water birds, mammals and humans as well. Up to this time, ten Metagonimus species are known mostly from Eastern and Southern Asia, namely M. yokogawai Katsurada, 1912, M. takahashii Suzuki, 1930, M...
Article
Full-text available
Location and tissue preference of filamental-type myxosporean plasmodia in histological slides of the gills can be properly identified only in cross sections of the gill filaments. The authors selected three myxosporeans (Myxobolus rutili, M. dispar and Henneguya psorospermica, parasites of the roach, the common carp and the pike, respectively) for...
Article
Infection of the cornea in fishes by Myxobolus plasmodia is a common but still little known site preference of myxosporeans. A sporadic but striking infection in the cornea of the roach (Rutilus rutilus) was observed in Lake Balaton, Hungary. Relatively small, round plasmodia 250 to 500 μm in diameter developed in the dense connective tissue of the...
Article
Full-text available
Metacercariae of species of the genus Apophallus Lühe, 1909, infecting the fins and skin of freshwater fishes, frequently cause black spot disease. Two species, Apophallus muehlingi (Jägerskiöld, 1899) and A. donicus (Skrjabin & Lindtrop, 1919), are known to occur in Hungarian fishes. It has generally been thought that metacercariae of A. muehlingi...
Poster
Full-text available
Ichtyophthiriasis or white spot disease, caused by the parasitic ciliate Ichthyophthirius multifiliis, is affecting wild and aquacultured freshwater fish worldwide. Morbidity and mortality due to the infection is associated with severe economic losses in aquacultured fish including common carp, rainbow trout, and channel catfish. Banning of malachi...
Presentation
The ParaFishControl project, which has been running since 2015, aims to research the parasites of the six most important fish species of European aquaculture. During the survey, the Opisthorchiid trematodes (Platyhelminthes: Digenea) of common carp (Cyprinus carpio) were monitored in Hungarian aquacultures. The metacercariae of these trematodes par...
Presentation
The ParaFishControl project, which has been running since 2015, aims to research the parasites of the six most important fish species of European aquaculture. During the survey, the Opisthorchiid trematodes (Platyhelminthes: Digenea) of common carp (Cyprinus carpio) were monitored in Hungarian aquacultures. The metacercariae of these trematodes par...
Presentation
Full-text available
The aim of this study was to examine the occurrence of difference Myxozoan species infecting the wild and cultured fishes from Setiu Wetlands, Malaysia. Six species of common estuarine fish species such as Scatophagus argus (leopard scat; n=20), Toxotes jaculatrix (archerfish; n=17), Tetraodon nigroviridis (puffer fish; n=11), Siganus javus (streak...
Article
In a parasitology survey of Hungarian fishes, heavy infections of parasitic copepods Lamproglena pulchella and a Lamproglena sp. were found in the gills of the asp and the European catfish, respectively. Individuals of both fish species were emaciated and infected with hundreds of Lamproglena. Copepods located close to the tip of gill filaments and...
Article
Full-text available
A szerzők jelen tanulmányukban a hazai angolna indukált szaporítási kísérletek során nyert ikrákon megtelepedő baktériumos fertőzések felmérését és a védekezés i lehetőségek feltérképezését tűzték ki célul. A mikrobiológiai vizsgálatok során egyetlen uralkodó faj, a V. cyclitrophicus került izolálásra. Megjelenése a kísérleti rendszerben a mestersé...
Article
Full-text available
Species of the cnidarian genus Henneguya Thélohan, 1892 (Myxosporea: Myxobolidae) are histozoic parasites commonly found in freshwater and, more rarely, in marine fish. The development of these parasites in fish tissues includes the formation of plas-modia within which occurs the sporogony originating spores with two caudal processes, which are usu...
Article
In a goldfish stock held in a pet fish pond, heavy coccidian infection, caused by an epicellularly developing Goussia species, appeared in April of 3 consecutive years. The shape and size of its oocysts resemble to an inadequately described species, Goussia carassiusaurati (Romero-Rodrigez, 1978). In histological sections, gamogonic and sporogonic...
Article
Full-text available
Molnár et al. (2015) reported two types of echinostomatid metacercariae in the lateral line organ of Hungarian fish species. Type 1 metacercariae possessed 27 collar spines and 16 uniform and three larger dorsal spines, whereas Type 2 metacercariae bore 27 collar spines and 19 equal-sized dorsal spines. In the recent work, molecular studies carried...
Article
Full-text available
The prevalence and distribution of piscine circoviruses (CVs) were tested in a routine virus monitoring programme in Lake Balaton, Hungary. A high prevalence of European eel CV (EeCV) was found in the apparently healthy eel population (35.5%). The copy number of the viral DNA in different organs was determined by quantitative real-time PCR. The res...
Article
During a general annual fish health survey in natural waters and ponds, epitheliocystis infections were recorded in fingerlings of two cyprinid fish species, the cultured common carp and the wild gibel carp. Benign and heavy infections were equally observed without mortality. In addition to the general health inspection of fish, histopathological e...
Article
Full-text available
During a survey of myxosporean parasites of freshwater fishes in Meerut, Uttar Pradesh (UP), India, spores of Henneguya chaudhuryi (Bajpai & Haldar, 1982) were found in the gill lamellae of the spotted snakehead fish Channa punctata (Bloch) (Perciformes: Channidae). This species was described lacking several characteristics in the original descript...
Article
Full-text available
Thelohanellus kitauei is a freshwater myxosporean parasite causing intestinal giant cystic disease of common carp. To clarify the life cycle of T. kitauei, we investigated the oligochaete populations in China and Hungary. This study confirms two distinct aurantiactinomyxon morphotypes (Aurantiactinomyxon type 1 and Aurantiactinomyxon type 2) from B...
Article
Full-text available
In the summer of 2014, mass mortality of the sichel, Pelecus cultratus (L.), was observed in Lake Balaton, Hungary. Parasitological examination conducted in the framework of a complete diagnostic survey revealed myxozoan infections. Two species of Myxobolus Bütschli, 1892 were found, one in the gill lamellae and another in the eyes. Following this...
Article
Full-text available
Myxozoans (Cnidaria: Myxozoa) are almost exclusively endoparasites of aquatic vertebrates and invertebrates, with the notable exception being two species of Soricimyxum Prunescu, Prunescu, Pucek et Lom, 2007 described from terrestrial shrews (Soricidae) in central Europe. Myxospores of the two parasites are morphologically indistinguishable, but ha...
Article
Full-text available
Ten new types of sphaeractinomyxon actinospores are morphologically and molecularly described from the coelomic cavity of two marine oligochaete hosts, Limnodriloides agnes (Hrabě, 1967) and Tubificoides pseudogaster (Dahl, 1960), from Aveiro estuary, Portugal. The smallest sphaeractinomyxon type measured 17 μm (length) × 19 μm (width) × 19 μm (api...
Article
In a cultured pikeperch (Sander lucioperca) stock the monopisthocotylean monogenean gill parasite Ancyrocephalus paradoxus caused heavy infection and mortalities. The gills of the affected fish specimens were infected by 50 to 800 monogenean parasites. Severe pathological changes were found in areas where the worms attached to the gills. At the att...
Article
Full-text available
Balantidium ctenopharyngodoni is a common ciliate in Hungary, infecting the hindgut of grass carp (Ctenopharyngodon idella), a cyprinid fish of Chinese origin. Although data have already been presented on its occasional pathogenic effect on the endothelium of the host, generally it is a harmless inhabitant of the gut. Phylogenetic analysis of the 1...
Article
In parasite surveys of fishes from Lake Balaton and its tributaries in Hungary, infections with metacercariae of a species of the digenean genus Echinochasmus (Trematoda: Echinostomatidae) were found in seven species of fish. In ruffe, Gymnocephalus cernuus, malformations of the gill filaments apparently caused by these infections were observed. Th...
Article
Full-text available
The objective of this study was to survey the incidence of Flavobacterium columnare in wild and cultured freshwater fish species in Hungary. This bacterium usually causes disease in waters of more than 25 °C temperature. However, with the introduction of intensive fish farming systems, infected fish exposed to stress develop disease signs also at l...
Article
Full-text available
In recent years and decades, two new fish species, the Caucasian dwarf goby (Knipowitschia caucasica) and the Amur sleeper (Perccottus glenii) have become members of the Hungarian fish fauna. In a 14-month study on the parasite fauna of these species, the authors detected 11 parasite species in the Caucasian dwarf goby and 17 species in the Amur sl...