Based on previous molecular phylogenetic analyses, Bothriocestus n. gen. is erected to accommodate bothriocephalid tapeworms that have an elongate scolex, a well-developed apical disc, and a narrow neck region, parasitize freshwater fishes in the Holarctic, and were previously placed in the polyphyletic genus Bothriocephalus Rudolphi, 1808 (Cestoda: Bothriocephalidea). Bothriocestus claviceps (Goeze, 1782) n. comb., a parasite of eels (Anguilla spp.) in the Holarctic region, is designated as the type species. Another species of the new genus, Bothriocestus cuspidatus (Cooper, 1917) (syn. Bothriocephalus cuspidatusCooper, 1917) is redescribed from type and voucher specimens, and new material from the type host, the walleye, Sander vitreus (Mitchill, 1818) (Perciformes: Percidae), in Manitoba and Ontario (where the type locality is located) (Canada) and in New York state and Wisconsin. Bothriocestus cuspidatus of S. vitreus is characterized primarily by the possession of a narrow, long strobila (total length up to 18 cm) composed of distinctly craspedote, trapezoidal proglottids, with primary, secondary, and tertiary proglottids differing in size, and by an arrow-shaped (=cuspidatus) scolex that is distinctly broader than the first proglottids, widest near the base in lateral view and gradually becoming broader toward the anterior end in dorsoventral view. A "dwarf" form of B. cuspidatus (total length of 9-27 mm) from Johnny darter, Etheostoma nigrum Rafinesque, 1820, and tessellated darter, Etheostoma olmstedi Storer, 1842 (both Percidae: Etheostominae), is also characterized morphologically in the present paper.

• MeSH
• Cestoda * MeSH
• cestodózy * veterinární   parazitologie   MeSH
• fylogeneze MeSH
• nemoci ryb * parazitologie   MeSH
• okounovití * parazitologie   MeSH
• Perciformes * parazitologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH
• Geografické názvy
• Ontario MeSH
• Severní Amerika MeSH

Myxozoans are a unique group of microscopic parasites that infect mainly fishes. These extremely reduced cnidarians are highly diverse and globally distributed in freshwater and marine habitats. Myxozoan diversity dimension is unknown in Mexico, a territory of an extraordinary biological diversity. This study aimed to explore, for the first time, myxozoan parasite diversity from fishes of the Neotropical region of Mexico. We performed a large morphological and molecular screening using host tissues of 22 ornamental and food fish species captured from different localities of Veracruz, Oaxaca and Chiapas. Myxozoan infections were detected in 90% of the fish species, 65% of them had 1 or 2 and 35% had 3 and up to 8 myxozoan species. Forty-one putative new species were identified using SSU rDNA phylogenetic analyses, belonging to two main lineages: polychaete-infecting (5 species) and oligochaete-infecting (36 species) myxozoans; from those we describe 4 new species: Myxidium zapotecus sp. n., Zschokkella guelaguetza sp. n., Ellipsomyxa papantla sp. n. and Myxobolus zoqueus sp. n. Myxozoan detection increased up to 6 × using molecular screening, which represents 3.7 × more species detected than by microscopy. This study demonstrated that Neotropical fishes from Mexico are hosts of a multitude of myxozoans, representing a source of emerging diseases with large implications for economic and conservation reasons.

• MeSH
• Cnidaria * genetika   MeSH
• fylogeneze MeSH
• Myxobolus * genetika   MeSH
• Myxozoa * genetika   MeSH
• nemoci ryb * epidemiologie   parazitologie   MeSH
• parazitární nemoci u zvířat * epidemiologie   parazitologie   MeSH
• ribozomální DNA genetika   MeSH
• ryby genetika   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Geografické názvy
• Mexiko MeSH

Recent examinations of some marine fishes from off the southern coast of Iraq revealed the presence of five species of Philometra Costa, 1845 (Nematoda: Philometridae): Philometra arabiensis sp. n. (males and females) from the ovary of the shrimp scad Alepes djedaba (Forsskål) (Carangidae, Carangiformes), Philometra psettoditis Moravec, Walter et Yuniar, 2012 (females) from the body cavity of the Indian halibut Psettodes erumei (Bloch et Schneider) (Psettodidae, Pleuronectiformes), Philometra terapontis Moravec, Gopalakrishnan, Rajkumar, Saravanakumar et Kaliyamoorthy, 2011 (female) from the ovary of the jarbua terapon Terapon jarbua (Forsskål) (Terapontidae, Centrarchiformes), Philometra sp. (females) from the ovary of the Arabian blackspot threadfin Polydactylus mullani (Hora) (Polynemidae, Carangariformes) and Philometra sp. 2 of Moravec et al. (2016a) (females) from the ovary and body cavity of the bartail flathead Platycephalus indicus (Linnaeus) (Platycephalidae, Perciformes). Philometra arabiensis sp. n. is mainly characterised by the length of spicules (198-243 μm) and gubernaculum (75-99 μm), the gubernaculum/spicule length ratio (1 : 2.33-2.79), the structure of the gubernaculum distal portion and the male caudal end, and the body length of males (1.86-2.73 mm). The present findings of P. psettoditis and P. terapontis in fishes of the Arabian Gulf represent new geographical records for these parasites.

• MeSH
• Dracunculoidea * MeSH
• korýši MeSH
• mikroskopie elektronová rastrovací MeSH
• nemoci ryb * epidemiologie   parazitologie   MeSH
• ovarium parazitologie   MeSH
• Perciformes * parazitologie   MeSH
• ryby parazitologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Irák MeSH

Dactylogyrus Diesing, 1850 is the most species-rich genus in Platyhelminthes, with over 900 documented species, that are mostly strictly specific to freshwater cyprinoids. The morphological Dactylogyrus groups afrobarbae-type, carpathicus-type, pseudoanchoratus-type, and varicorhini-type are known to occur in Africa. This study describes a new species of Dactylogyrus of the varicorhini-type from the gills of the endemic smallmouth yellowfish Labeobarbus aeneus (Burchell) from the Vaal River, Free State Province, South Africa. Dactylogyrus matlopong sp. n. is unique among its varicorhini-type congeners mainly by the accessory piece of the male copulatory complex that presents a hook-shaped subunit with defined round base not reaching the male copulatory organ, combined with the presence of a conspicuous medial projection on the anterior margin of the ventral bar. Sequences of the partial 28S and 18S rRNA genes, together with entire ITS1 region, were generated for the first time for a species of Dactylogyrus from South Africa. Concatenated phylogenetic analyses of selected Dactylogyrus spp. showed that these parasites group according to their morphological types.

• MeSH
• Cyprinidae * parazitologie   MeSH
• fylogeneze MeSH
• nemoci ryb * epidemiologie   parazitologie   MeSH
• ploštěnci * genetika   MeSH
• Trematoda * MeSH
• žábry parazitologie   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Jihoafrická republika MeSH

Ligula intestinalis (Linnaeus, 1758) is a tapeworm parasite with a worldwide distribution that uses a wide variety of fish species as its second intermediate host. In the present study, we investigated the prevalence and population genetic structure of plerocercoids of L. intestinalis in five common cyprinoid species, roach Rutilus rutilus (Linnaeus), freshwater bream Abramis brama (Linnaeus), white bream Blicca bjoerkna (Linnaeus), bleak Alburnus alburnus (Linnaeus), and rudd Scardinius erythrophthalmus (Linnaeus), collected in six water bodies of the Czech Republic (Milada, Most, Medard, Jordán, Římov and Lipno). Of the six study sites, the highest frequency of parasitism was recorded in Lake Medard (15%). The overall prevalence rate among the species was as follows: roach > rudd ≥ freshwater bream > bleak > white bream. Two mitochondrial genes (cytb and COI) were used to compare the population genetic structure of parasite populations using selected samples from the five fish species. The results of the phylogenetic analysis indicated that all populations of L. intestinalis were placed in Clade A, previously identified as the most common in Europe. At a finer scale, haplotype network and PCoA analyses indicated the possible emergence of host specificity of several mtDNA haplotypes to the freshwater bream. Moreover, pairwise Fixation indices (FST) revealed a significant genetic structure between the parasite population in freshwater bream and other host species. Parasite populations in roach not only showed the highest rate of prevalence but also depicted a maximum number of shared haplotypes with populations from bleak and rudd. Our results suggest that recent ecological differentiation might have influenced tapeworm populations at a fine evolutionary scale. Thus, the differences in prevalence between fish host species in different lakes might be influenced not only by the parasite's ecology, but also by its genetic diversity.

• MeSH
• Cestoda * genetika   MeSH
• cestodózy * epidemiologie   parazitologie   veterinární   MeSH
• Cyprinidae * parazitologie   MeSH
• fylogeneze MeSH
• genetické struktury MeSH
• interakce hostitele a parazita MeSH
• jezera MeSH
• mitochondriální DNA MeSH
• nemoci ryb * epidemiologie   parazitologie   MeSH
• paraziti * MeSH
• populační genetika MeSH
• prevalence MeSH
• voda MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH

Myxozoans are microscopic, metazoan, obligate parasites, belonging to the phylum Cnidaria. In contrast to the free-living lifestyle of most members of this taxon, myxozoans have complex life cycles alternating between vertebrate and invertebrate hosts. Vertebrate hosts are primarily fish, although they are also reported from amphibians, reptiles, trematodes, mollusks, birds and mammals. Invertebrate hosts include annelids and bryozoans. Most myxozoans are not overtly pathogenic to fish hosts, but some are responsible for severe economic losses in fisheries and aquaculture. In both scenarios, the interaction between the parasite and the host immune system is key to explain such different outcomes of this relationship. Innate immune responses contribute to the resistance of certain fish strains and species, and the absence or low levels of some innate and regulatory factors explain the high pathogenicity of some infections. In many cases, immune evasion explains the absence of a host response and allows the parasite to proliferate covertly during the first stages of the infection. In some infections, the lack of an appropriate regulatory response results in an excessive inflammatory response, causing immunopathological consequences that are worse than inflicted by the parasite itself. This review will update the available information about the immune responses against Myxozoa, with special focus on T and B lymphocyte and immunoglobulin responses, how these immune effectors are modulated by different biotic and abiotic factors, and on the mechanisms of immune evasion targeting specific immune effectors. The current and future design of control strategies for myxozoan diseases is based on understanding this myxozoan-fish interaction, and immune-based strategies such as improvement of innate and specific factors through diets and additives, host genetic selection, passive immunization and vaccination, are starting to be considered.

• MeSH
• adaptivní imunita * MeSH
• antiparazitární látky farmakologie   MeSH
• B-lymfocyty imunologie   metabolismus   parazitologie   MeSH
• imunitní únik MeSH
• imunoglobuliny imunologie   metabolismus   MeSH
• interakce hostitele a parazita MeSH
• Myxozoa účinky léků   imunologie   patogenita   MeSH
• nemoci ryb imunologie   metabolismus   parazitologie   prevence a kontrola   MeSH
• parazitární nemoci u zvířat imunologie   metabolismus   parazitologie   prevence a kontrola   MeSH
• přirozená imunita * MeSH
• ryby imunologie   metabolismus   parazitologie   MeSH
• T-lymfocyty imunologie   metabolismus   parazitologie   MeSH
• vakcíny farmakologie   MeSH
• vodní hospodářství MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH
• Research Support, U.S. Gov't, Non-P.H.S. MeSH

Proliferative kidney disease (PKD) is a widespread temperature-dependent disease in salmonids caused by the myxozoan parasite, Tetracapsuloides bryosalmonae (Canning, Curry, Feist, Longshaw et Okamura, 1999) (Tb). Tb has a two-host life cycle, involving fish as an intermediate host and freshwater bryozoans as the definitive host. Although salmonids are acknowledged as hosts for the parasite, it is less clear which fish species are active hosts in the life cycle of Tb. Differences in infection dynamics have been observed between some fish species, which are thought to be related to the existence of two main Tb-strains, the American and European. Iceland, having three species of indigenous salmonids and positioned geographically between Europe and North America, is an ideal location to study the natural development of Tb in wild fish. The main aim of this study was to determine the genetic origin of Tb in Iceland and confirm whether mature spores are produced in Icelandic salmonids. In this study, Icelandic salmonids were infected with the European Tb-strain. In situ hybridisation revealed that intraluminal sporogonic stages, including mature spores, were commonly observed in all three salmonid species. The presence of intraluminal stages has previously been confirmed in brown trout Salmo trutta Linnaeus and Atlantic salmon S. salar Linnaeus in Europe, but they have only been observed in Arctic charr Salvelinus alpinus (Linnaeus) in North America, infected by the local strain. This is, therefore, the first time that sporogonic stages have been observed in Arctic charr in Europe, where fish are infected with the European Tb-strain. Our data strongly suggest that all the three salmonid species inhabiting Icelandic waters serve as active hosts in the life cycle of Tb. However, for full confirmation, transmission trials are needed.

• MeSH
• hybridizace in situ veterinární   MeSH
• interakce hostitele a parazita * MeSH
• Myxozoa růst a vývoj   fyziologie   MeSH
• nemoci ryb parazitologie   MeSH
• parazitární nemoci u zvířat parazitologie   MeSH
• pstruh * MeSH
• Salmo salar * MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

The proteocephalid genus Pseudoendorchis (Cestoda: Onchoproteocephalidea) has recently been proposed to accommodate seven species/species-level lineages of tapeworm parasites of catfishes (Siluriformes) in the Neotropical region, based on integration of genetic information, and morphological and ecological data. Its members are typified by having a large Mehlis' gland, representing more than 1/5 (usually 1/4-1/2) of proglottid width, and the vagina always anterior to the cirrus-sac. Critical examination of previously unstudied museum cestodes tentatively designated as Pseudoendorchis sp. 3 from Megalonema platycephalum (Pimelodidae) in the Peruvian Amazon made it possible to formally describe this taxon and to differentiate it from all congeneric species. The new species, which is the first parasite of M. platycephalum ever recorded, is characterised mainly by having the scolex bearing four uniloculate suckers (biloculate in all nominal species of the genus), the lowest relative surface of the ovary (ratio of its surface to that of the whole proglottid) among species of the genus (< 9% versus > 11%, usually 15-20%), and an extraordinarily large Mehlis' gland (its diameter represents 41-50% of proglottid width). Morphology of the terminal portion of the vaginal canals in proteocephalids is briefly discussed.

• MeSH
• Cestoda * MeSH
• cestodózy * parazitologie   MeSH
• druhová specificita MeSH
• nemoci ryb * parazitologie   MeSH
• sumci * parazitologie   MeSH
• vagina MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

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.

• MeSH
• fylogeneze MeSH
• interakce hostitele a parazita * MeSH
• Myxobolus anatomie a histologie   klasifikace   genetika   ultrastruktura   MeSH
• nemoci ryb parazitologie   MeSH
• parazitární nemoci u zvířat parazitologie   MeSH
• Perciformes * MeSH
• střeva parazitologie   patologie   MeSH
• transmisní elektronová mikroskopie veterinární   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Saudská Arábie MeSH

Adult trematodes of Allocreadium Looss, 1900 (Digenea) infect the intestine of mostly freshwater fishes in Asia, Europe, Africa and the Americas. During routine parasitological surveys in the Vaal River system, adult trematodes were collected from the intestine of smallmouth yellowfish, Labeobarbus aeneus (Burchell). The trematodes were confirmed to represent a member of Allocreadium and did not match any existing taxon. Therefore, they are described as a new species, Allocreadium apokryfi sp. n. The morphology of the new species most closely resembles that of Allocreadium aswanense El-Naffar, Saoud et Hassan, 1984, but it differs from it by having a bipartite internal seminal vesicle, wider eggs, a shorter intertesticular distance, an intestinal bifurcation at the ventral sucker level, a ventral sucker that is larger than the oral sucker, and a genital pore near the intestinal bifurcation or the ventral sucker. The surface topology of the new species is notably different from that of other allocreadiids. Papillae were observed in the ventral sucker and surrounding both ventral and oral suckers, but the number and arrangement of the latter were not consistent among specimens. The protruding cirrus of A. apokryfi sp. n. was described using SEM and is the first such observation for the genus. Genetic characterisation showed that the new species was clearly distinct from other Allocreadium spp. using both 18S (nucleotide difference 1.3-9.1%) and 28S (4.7-6.5%) rDNA, forming a well-supported clade in Allocreadium. The presence of A. apokryfi sp. n. in a well-studied river is unexpected, and considering the diet of its host and the scarcity of Allocreadium in Africa, the possible biology of this species is discussed herein.

• MeSH
• biologická evoluce MeSH
• Cyprinidae * MeSH
• infekce červy třídy Trematoda epidemiologie   parazitologie   veterinární   MeSH
• interakce hostitele a parazita * MeSH
• nemoci ryb epidemiologie   parazitologie   MeSH
• prevalence MeSH
• Trematoda fyziologie   MeSH
• zvířata MeSH
• zvláštnosti životní historie MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Jihoafrická republika MeSH