Folia Parasitologica最新文献

The nematode Spinitectus notopteri Karve et Naik, 1951 was collected from two species of freshwater fish belonging to the family Notopteridae, namely Chitala ornata (Gray) and Notopterus notopterus (Pallas), at Khun Thale Swamp in Surat Thani province of southern Thailand. The overall prevalence of the parasite was found to be 88% (94 fish infected/106 fish examined). A higher prevalence was found in C. ornata (96%), while a higher intensity was noted for N. notopterus (117 parasites/fish). The most important morphological characters were the presence of cephalic and cuticular structures, precloacal ridges, and genital papillae. Specimens were genetically characterised using cox1 mtDNA. Morphological characteristics were most similar to Spinitectus petterae Boomker, 1993 from Clarias gariepinus (Burchell) in Africa, while the genetic data were dissimilar to all available data for the genus. Therefore, the identification of nematode specimens using a combination of morphological and molecular techniques is stressed. This study also presents the first molecular analysis of S. notopteri infecting Thai freshwater fish and a new geographical record for S. notopteri.

Setaria spp. are vector-borne parasitic roundworms commonly found in the abdominal cavities of wild and domesticated ungulates globally. The objective of this study was to conduct a morphological and molecular analysis of Setaria tundra Issaitshikoff et Rajewskaya, 1928, collected from roe deer Capreolus capreolus Linnaeus in Lithuania. The morphological characteristics of S. tundra described and illustrated. The amplification of the 12S rRNA and 18S rRNA genes confirmed the presence of S. tundra. This is the first case report of S. tundra in roe deer in Lithuania.

Equine neosporosis is an intracellular protozoan disease with a global distribution, affecting a diverse range of warm-blooded animals. Neospora caninum Dubey, Carpenter, Speer, Topper et Uggla, 1988 is associated with foetal loss, neurological disease and abortion in equids. No information was available regarding equine N. caninum infection among equids in Iraq. Thus, the aim of this study was to determine the prevalence rate of N. caninum in equines by using a competitive enzyme-linked immunosorbent assay (c-ELISA). A total of 329 blood samples randomly selected from equines, comprising 268 horses and 61 donkeys were examined. The seroprevalence rate of N. caninum was determined as 46% (28/61) for donkeys and 24% (64/268) for horses. The prevalence of N. caninum indicated a significantly higher risk of infection in donkeys compared to horses (P < 0.001). However, the odds of N. caninum infection in draught equids were 8.2 times greater than other equids with a significant difference (P < 0.001). The current study revealed no significant differences in the prevalence of N. caninum across various genders, breeds, clinical statuses, disease histories and among equids that had contact with dogs. While outdoor feeding and mixed (grazing), showed a significant difference (P = 0.003) and (P = 0.75), respectively, in the presence of antibodies against N. caninum compared to indoor feeding (stable). Moreover, the odds of infection in equids with a history of late abortion were 4.8 times higher than those without such a history of abortion (2.20-10.56) with statistical significance (P < 0.001).

Trichomoniasis, a globally distributed sexually transmitted infection, is caused by the urogenital parasite Trichomonas vaginalis Donné, 1836 affecting both women and men. The treatment of choice is metronidazole (MTZ). In the present study, 15 samples of vaginal discharge and urine were analysed by sequencing nitroreductase genes (ntr4 and ntr6). An in silico model was structured to illustrate the location of point mutations (PM) in the protein. The ntr4 gene presented four PMs: G76C (10/10), C213G (9/10), C318A (5/10) and G424A (1/10), while the ntr6 gene had eight PMs; G593A (13/13) the most frequent, G72T and G627C, both in 8/13. The PM C213G and A438T generated a stop codon causing a truncated nitroreductase 4 and 6 protein. Docking analysis demonstrated that some models had a decrease in binding affinity to MTZ (p < 0.0001). A high frequency of mutations was observed in the samples analysed that could be associated with resistance to MTZ in Chile.

The parasite fauna of Neotropical reptiles is poorly known, and the number of parasites described in these hosts does not seem to correspond to the actual species diversity in this zoogeographical region. This also applies to tapeworms such as proteocephalids, which are rarely found in reptiles and are strictly specific to their reptilian hosts. In the present paper, three new species of Ophiotaenia La Rue, 1911 are described from three dipsadine snake species (Squamata: Colubridae) in Ecuador, namely O. jeanmarctouzeti sp. n. from the Neotropical blunt-headed treesnake Imantodes cenchoa (Linnaeus), O. barraganae sp. n. from the beautiful calico snake Oxyrhopus formosus (Wied-Neuwied) and O. velascoae sp. n. from the forest flame snake Oxyrhopus petolarius (Linnaeus). The new species are characterised by type 1 uterine development, the number and distribution of testes, the size of the scolex and other metric features. As no molecular data are available on the specimens collected more than 35 years ago, the phylogenetic relationships of the individual taxa are not known.

Tapeworms of the genus Proteocephalus Weinland, 1858 (Cestoda: Proteocephalidae) are common and widespread intestinal parasites of whitefish (Coregonus spp., Salmonidae: Coregoninae). Previous taxonomic studies, based solely on morphology and inconsistently fixed specimens, concluded that all salmoniform fish, including whitefish, are parasitised by a single euryxenous and highly polymorphic species, Proteocephalus longicollis (Zeder, 1800). However, recent molecular phylogenetic analyses have revealed the existence of several species specific to individual genera or even species of salmoniform fish. In this study, Proteocephalus fallax La Rue, 1911 is redescribed based on newly collected and genetically characterised specimens from several Coregonus species in Switzerland, the type locality of the species, and in Norway. This cestode was previously synonymised with P. exiguus La Rue, 1911, a parasite of whitefish in North America, but the two species are not closely related. Proteocephalus fallax differs from P. exiguus in its larger body size, wider proglottids, shorter cirrus sac and broader scolex. In addition, the other Proteocephalus species described in whitefish are briefly discussed, with comments on their validity, host range and distribution.

Multivalvulidan myxosporeans (Multivalvulida) of the genera Unicapsula Davis, 1924 and Kudoa Meglitsch, 1947 are mostly causative agents of latent and imperceptible infection in marine fishes. However, they are sometimes incriminated in causing post-mortem myoliquefaction or unsightly cyst formation in commercial fish. Despite the great commercial impacts of multivalvulidan infection, the biodiversity, host range and epidemiology of multivalvulidan species remain to be explored further, including infection of alternative annelid hosts. Therefore, this study aimed to identify multivalvulidan species and their host and/or distribution records in commercial fishes in China. Multivalvulidan infection was detected in ten commercial fish species of seven families from the South and East China Seas (Northwest Pacific Ocean) and the Eastern Central Atlantic Ocean (an imported Dagetichthys lusitanicus [de Brito Capello]). Based on morphological and molecular-genetic analyses of their small and large subunit of ribosomal RNA genes, five new host and/or geographical distribution records for five fish species are presented, and three new species in five fish species are described, namely Kudoa neoscomberomori sp. n. in Scomberomorus commerson (Lacépède); Kudoa pilosa sp. n. in Helicolenus hilgendorfi (Döderlein) (type host) and Sebastiscus tertius (Barsukov et Chen); and Kudoa tumidisporica sp. n. in Photopectoralis bindus (Valenciennes) (type host) and Nuchequula nuchalis (Temminck et Schlegel). This study provides new data on multivalvulidan diversity in the ocean ecosystem.

In this review, I take the first-person perspective of a neuroscientist interested in Toxoplasma gondii (Nicolle et Manceaux, 1908). I reflect on the value of behavioural manipulation as a perturbation tool to understand the organisation of behaviour within the brain. Toxoplasma gondii infection reduces the aversion of rats to the olfactory cues of cat presence. This change in behaviour is one of the often-discussed exemplars of host-parasite coevolution, culminating in the manipulation of the host behaviour for the benefit of the parasite. Such coevolution also means that we can use host-parasite systems as tools to derive fundamental insights about the host brain itself.

Toxoplasmosis is caused by Toxoplasma gondii (Nicolle et Manceaux, 1908), a coccidian protist (Apicomplexa). It has a strong predilection for infecting the central nervous system. Researchers have therefore investigated its association with several neurological and psychiatric disorders, including Alzheimer's disease, attention-deficit hyperactivity disorder, autism, bipolar disorder, cerebral palsy, depression, Guillain-Barre syndrome, multiple sclerosis, obsessive compulsive disorder, Parkinson's disease, personality disorders, and schizophrenia. Among these disorders the strongest evidence for a role of T. gondii exists for psychosis in general and schizophrenia in particular. This paper reviews the origins of this association, briefly summarises the current evidence in support, and discusses future research strategies.

Myxozoans are microscopical parasites widely distributed in fish, with over 2,600 described species, but their actual diversity is still underestimated. Among salmonids, more than 70 myxozoan species have been identified. This study focuses on species of Chloromyxum Mingazzini, 1890 that infect salmonid kidneys, particularly C. majori Yasutake et Wood, 1957 and C. schurovi Shulman et Ieshko, 2003. Despite their similar spore morphology, they exhibit distinct host preferences, tissue affinities and geographical distributions. Chloromyxum schurovi predominantly infects the renal tubules of Salmo salar Linnaues and S. trutta Linnaeus in Europe, while C. majori targets the glomeruli of Oncorhynchus mykiss (Walbaum) and O. tshawytscha (Walbaum) in North America. The sequence data for C. majori and C. schurovi have been either missing or questionable. In our study, we examined the kidneys of two salmonid species for chloromyxid infections, using both morphological and molecular data to characterise Chloromyxum species in salmonids. The sequence of C. schurovi obtained in our study did not match the previously published parasite data. Instead, it clustered as an independent lineage sister to the Paramyxidium Freeman et Kristmundsson, 2018 clade gathering the species from various fish organs, including the urinary tract. Our findings clarified the taxonomic origin of the previous C. schurovi sequence as Myxidium giardi Cépède, 1906, highlighting the risks associated with the presence of myxozoan blood stages in the bloodstream of their fish host and the challenges of non-specific PCR amplification. We redescribe C. schurovi, thus contributing to a better understanding of the diversity and phylogeny of kidney-infecting species of Chloromyxum.