Taxonomy Of Helminths Research Articles

Epidemiology and Integrative Taxonomy of Helminths of Invasive Wild Boars, Brazil

Wild boars (Sus scrofa) are a significant invasive species in Brazil. We evaluated the helminth diversity of 96 wild boars in São Paulo state. Helminth infection descriptors were calculated, the species were identified and their 18S, 28S rDNA and internal transcribed spacer (ITS) regions were amplified for phylogenetic analyses. Ascarops strongylina, Strongyloides ransomi, Globocephalus urosubulatus, Oesophagostomum dentatum, Trichuris suis, Metastrongylus salmi, Metastrongylus pudendotecus, Ascaris suum and Stephanurus dentatus and Macracanthorhynchus hirudinaceus were identified. Globocephalus urosubulatus had the highest prevalence and mean abundance, and most animals had mixed infections with three parasite species. There was no association between parasite intensity and prevalence and host sex and body condition index (p > 0.05). Novel DNA sequences were obtained from G. urosubulatus, A. strongylina, and S. dentatus. This is the first study on the helmint diversity of non-captive wild boars in Brazil, and the first report of the occurrence of M. hirudinaceus, G. urosubulatus and S. dentatus in Brazilian wild boars. Non-captive wild boars of São Paulo State did not act as capture hosts for native helminth species but maintained their typical parasites, common to domestic pigs. They may act as parasite dispersers for low-tech subsistence pig farming and for native Tayassuidae.

Fauna, ecology and taxonomy of helminths of cypriniformes fish water bodies of Uzbekistan

Due to intensive human activities related to the use of water resources, has undergone substantial qualitative and quantitative changes of biocenosis and the fish community. This inevitably arise parasitic fish diseases that lead to a decrease in the number of valuable species and the deterioration of the epizootic situation reservoirs. Fauna of parasitic worms of Cypriniformes ponds diverse river of the Syrdarya shown 49 species. 18 species belongs to the class Trematoda, Cestoda class represented by 13 species, class Acanthocephala - 4, and the class Nematoda - 14. Analysis of biological properties and ecological of specialty parasitic worms Cypriniformes allows three types of communities: helminths (25 species), parasitizing Cypriniformes as definitive hosts; helminths (19 species), parasitizing Cypriniformes as intermediate hosts; - helminths (6 species), parasitizing Cypriniformes as a reservoir (=paratenetic) hosts.

A checklist of the parasitic helminths of cricetid and heteromyid rodents in Mexico

Abstract We present an updated checklist of helminth species infecting cricetid and heteromyid rodents (Rodentia: Cricetidae and Heteromyidae) distributed in Mexico. For each helminth record, we include information on helminth taxonomy, location within the host, life stage, host associations, collection localities, citation, and museum collections, when available. We recorded more than 73 helminth species from 47 host species distributed across 21 states in Mexico. The present list represents the most up-to-date knowledge of helminth species infecting cricetid and heteromyid rodents in Mexico.

Taxonomy of Physaloptera mirandai (Nematoda: Physalopteroidea) based in three-dimensional microscopy and phylogenetic positioning

Gastrointestinal nematodes are important ecological assets for the maintenance of the biodiversity in the Atlantic Forest in Brazil. They parasitize a number of animals of the local fauna, in which some species can promote serious injuries in the stomach wall of their hosts, which may lead to death. Among these nematodes, parasites of the genus Physaloptera are known to parasitize mammals (particularly carnivores and small rodents), birds and reptiles, being important for the local biodiversity. In this work, three hundred and sixty-two nematodes were recovered from the stomach of twenty-one Metachirus nudicaudatus (Didelphimorphia: Didelphidae) collected in Duas Bocas Biological Reserve, State of Espírito Santo, one of the largest Atlantic Forest remnants and important wildlife refuge of the Atlantic Forest in Brazil. Analysis using fluorescence and scanning electron microscopy as well as phylogenetic assessment using the mitochondrial cytochrome c oxidase subunit I gene showed that the parasites belong to the Physaloptera. Our results show details of the nematode morphology including the cloacal papillae distribution, cuticular topography details, 2D and 3D measurements of the structures with taxonomic importance. Molecular data confirmed the validity of P. mirandai and the phylogeny supported the monophyly of the assemblage formed by Physaloptera and Turgida. The use of a combination of quantitative and multidimensional microscopy tools, such as 3D reconstruction and modeling, allied to phylogenetic analysis may provide grounds for a new approach on helminth taxonomy and structural characterization.

A Simple and Efficient Method to Observe Internal Structures of Helminths by Scanning Electron Microscopy

Morphological studies of helminths by scanning electron microscopy are generally limited to the external topography of the organisms. In this work, we present a simple technique using ethanol as a cryoprotectant without postfixation in osmium tetroxide that allows for observation of the inner organization of helminths and preserves cellular structures. We tested the technique in three helminths: Echinostoma paraensei, Cruzia tentaculata, and Hassalstrongylus epsilon. The results show that this technique could potentially be applied to study the morphology, ultrastructure, and taxonomy of helminths.

Modern Parasitology: A Text of Parasitology

This textbook consists of 10 chapters written by highly respected senior scientists, all of whom have made major contributions to the field of parasitology. The first three are on systematic descriptions of) the medically important protozoa (Chapter 1), the helminths (Chapter 2), and vectors (Chapter 3). The fourth chapter is on epidemiology and this is followed by chapters on biochemistry (Chapter 5), molecular biology and molecular genetics (Chapter 6), physiology and nutrition (Chapter 7), immunity (Chapter 8), chemotherapy (Chapter 9) and finally control methods (Chapter 10). The text is written for undergraduate and graduate students taking their first parasitology course. The first three chapters are basically brief listings and descriptions of the various taxa of human parasites and their vectors. These chapters lack details. For example, in Chapter 2 additional information and specific examples on the use of isoenzymes in helminth taxonomy as well as more examples on parasite and host circadian and diurnal rhythms would have been helpful.

Angiostrongylus schmidti sp. n. (Nematoda: Metastrongyloidea) from the Rice Rat, Oryzomys palustris, in Florida, with a Key to the Species of Angiostrongylus Kamensky, 1905

Angiostrongylus schmidti sp. n., from the the pulmonary arteries of Oryzomys palustris in Florida, can be distinguished from A. tateronae and A. sandarsae by its shorter spicules (215 to 279 ,u) and larger ventroventral rays. A key is given to the species of the genus Angiostrongylus. During a study of the helminth parasites of the rice rat, Oryzomys palustris (Harlan), in north-central Florida, an undescribed species of metastrongylid lungworm was found in the pulmonary arteries. The nematode occurred in six of 53 rats trapped from Paynes Prairie, Alachua County, Florida, and three of 55 rice rats trapped near Cedar Key, Levy County, Florida. The rats were collected in the months of April through August 1970. Following the opinions of Dougherty (1946) and Alicata (1968), the new species is included in the genus Angiostrongylus, despite the presence of a gubernaculum. Only three species of Angiostrongylus have been previously described from North America: A. gubernaculatus Dougherty, 1946, from the badger and striped skunk, and A. blarini Ogren, 1954, and A. michiganensis Ash, 1967, from shrews. This species is named in honor of Dr. Gerald D. Schmidt, in recognition of his contributions to helminth taxonomy. Unless otherwise indicated, all measurements are in microns. Drawings were made with the aid of a Bausch and Lomb microprojector. Angiostrongylus schmidti sp. n. (Figs. 1-5)