PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “STRONGYLOIDEA”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources

Viability of eggs, filariform larvae and adults of Strongyloides venezuelensis (Nematoda: Strongyloidea) maintained in vitro.

The present study was performed to check the viability of eggs, filariform larvae and adults of Strongyloides venezuelensis exposed to various conditions for an in vitro maintenance. The eggs in the feces remained viable for about 25 days at 4 degrees C and 15 days at room temperature. However, the isolated eggs in sterile saline lost their viability within 24 hr at 4 degrees C. The eggs in morula stage were very sensitive to air drying and rapidly lost their viability (< or = 12 hr). Filariform larvae survived for a maximum period of 45 days in fecal suspension and 28 days in 0.12% nutrient broth in polyvinyl culture bags maintained at 20 degrees C. On the other hand, those isolated from nutrient broth cultures survived for a maximum period of 32 days in tap water and 22 days in sterile saline at 20 degrees C. The mature adult worms obtained from experimentally infected rats survived maximally for 9 days in serum supplemented (10% rat-serum) 0.12% nutrient broth and 4 days in serum free nutrient broth at 37 degrees C while the culture media were changed at an alternate day. The adult female worms deposited fertile eggs in serum supplemented and serum free nutrient broth cultures, however, the hatched larvae (L1) were not able to develop to the filariform stage in the culture media and found to die within 24 hr of maintenance. The present findings on an in vitro maintenance of different stages of S. venezuelensis may provide useful information for biological and biochemical studies with Strongyloides species.

Animals↗

Occurrence of Strongylidae (Nematoda: Strongyloidea) in Polish horses "tarpans" from Popielne Reserve.

The study was performed to evaluate intensity of strongylid infection in stabled tarpans using the method of collecting worms after anthelmintic treatment and in wild tarpans from Popielne reserve on the basis of faecal examination. After treatment with ivermectin 12 cyathostomes and one large strongyle species were recovered from the faeces of two tarpans. The most abundant cyathostome species were C. catinatum, C. pateratum, C. longibursatum, C. nassatum and C. coronatus. A higher intensity of infections with small strongyles (cyathostomes) was found in stabled group than in the group from the reserve. Large strongyles were more prevalent in wild tarpans, with Strongylus vulgaris as most common species (66.7%), but the intensity of infection was low. The present results are compared with earlier studies of horses in Poland and other countries. The results confirm the stability of cyathostomes in different breed of horses over the world.

Animals↗

Prevalence and abundance of equine strongyles (Nematoda: Strongyloidea) in tropical Australia.

A postmortem survey of 57 horses in tropical northern Queensland revealed 41 (89%) infected with intestinal strongyles. Thirty-five strongyle species (8 large strongyles and 27 small strongyles [Cyathostominae]) were recorded of which 9 species are reported from Australia for the first time. The 14 most prevalent small strongyles were Cyathostomum catinatum (in 76% of horses), Cyathostomum coronatum (65%), Cyathostomum pateratum (33%), Cyathostomum labiatum (30%), Cylicostephanus calicatus (70%), Cylicostephanus longibursatus (67%), Cylicostephanus goldi (43%), Cylicostephanus minutus (26%), Cylicocylus nassatus (67%), Cylicocyclus leptostomus (41%), Cylicocylus insigne (41%), Cylicocyclus radiatus (33%), Cylicocyclus brevicapsulates (22%), and Poteriostomum imperidentum (24%). The remaining cyathostomes were each found in less than 15% of horses. The 4 most common large strongyles were Triodontophorus serratus (30%), Strongylus vulgaris (28%), Strongylus equinus, and Strongylus edentatus (both 22%). The number of species of small strongyles per horse showed a marked variation (mean 10.3, range 2-21) but bore no relationship to either the total number of strongyles per horse, age, sex, and breed of horse, or season. Total number of strongyles per horse (mean 15,890, range 20-165,000) was less than in recent surveys in Europe and the U.S.A. Most horses had low worm burdens, whereas a very small number were heavily infected. Ninety-seven per cent of the total strongyle counts were small strongyles. Strongylus species contributed just over 1%. Small numbers of large strongyles per horse were usual with T. serratus (mean 570), S. vulgaris (mean 330), and S. equinus (mean 330) the most numerous.(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗

[Value of an antiparasitic treatment against Strongyloidea and Coccidia in Djallonke ewes at lambing].

Three groups of 14 Djallonke ewes each have been compared: group E received one antiparasitic treatment with Ivermectin, or Valbazen and Amprol at lambing, group T2 received three classical antiparasitic treatments with the same drugs according to the seasons (at the beginning and at the end of the long rainy season, and at the end of the short rainy season) group T1 remained untreated. The onset of sexual activity occurred 71.5 +/- 5.4 days (lot E), 74.5 +/- 6.3 (lot T2) and 104.3 +/- 10.3 (lot T1) after lambing. So, intervals between lambings were 255.7 +/- 11.8 (lot E), 245.9 +/- 13.5 (lot T2) and 298.2 +/- 24 (lot T1). Lambing other characteristics were almost the same in the three groups: prolificacy 127-137%, weight at birth 1.2-1.4 kg, daily weight gains (0-90 days) 99-114 g and mortality 39-48%. It seems economically more profitable to treat against internal parasites once at lambing rather than three times a year according to the seasons.

Animals↗

[Prevalence and control of gastrintestinal parasitosis in calves from dairy farms in the municipality of Alegre, Espírito Santo].

The objectives of the present study were to evaluate the prevalence of gastrintestinal helminthosis of calves and to identify control aspects related to these infections in dairy farms of the municipality of Alegre, Espírito Santo. A total of 222 calves varying of one to 18 months of age were examined and proportionally divided between 12 dairy farms. After techniques in the laboratory of parasitic diseases of the veterinary hospital of Centro de Ciências Agrárias of the Universidade Federal do Espírito Santo, the prevalence of eggs of Strongyloidea, Trichuris sp., Moniezia sp, Strongyloides papillosus and coccidial oocysts were, in properties and calves: 100 and 66; 100 and 57.8; 50 and 8.2; 25 and 1.8, and 33.3 and 7.8%, respectivelly. Of the 66 for eggs of the Strongyloidea, 64 were attributed to Haemonchus spp. and 53.75% to Cooperia spp. Despite the existence of parasite control programs in the farms, were identify some wrong practices, as lack of weighting animals for the calculation of the dose rate of the drugs and lack of use of the compost of excrements. Thus, the drugs uses of incorrect form may be able to cause future damages with development of parasites resistance to these products.

Animals↗

Systematic relationships of some members of the genera Oesophagostomum and Chabertia (Nematoda: Chabertiidae) based on ribosomal DNA sequence data.

The present study characterised seven species of the Chabertiidae (Nematoda: Strongyloidea) belonging to either the subfamily Oesophagostominae (Oesophagostomum radiatum, Oesophagostomum venulosum, Oesophagostomum dentatum, Oesophagostomum quadrispinulatum, Oesophagostomum columbianum, Oesophagostomum bifurcum) or to the subfamily Chabertiinae (Chabertia ovina) by their second internal transcribed spacer rDNA sequence, assessed the extent of intraspecific variation and interspecific differences in the sequence, and inferred the phylogenetic relationship of C. ovina with respect to members of the Oesophagostominae. In both the phenetic and cladistic analyses of the sequence data, Chabertia was nested within Oesophagostomum, suggesting either that the species examined represent members of the same genus, or alternatively, that Oesophagostomum may represent more than one genus.

Animals↗

Phylogeny of Dictyocaulus (lungworms) from eight species of ruminants based on analyses of ribosomal RNA data.

In this study, we conducted phylogenetic analyses of nematode parasites within the genus Dictyocaulus (superfamily Trichostrongyloidea). Lungworms from cattle (Bos taurus), domestic sheep (Ovis aries), European fallow deer (Dama dama), moose (Alces alces), musk ox (Ovibos moschatus), red deer (Cervus elaphus), reindeer (Rangifer tarandus) and roe deer (Capreolus capreolus) were obtained and their small subunit ribosomal RNA (SSU) and internal transcribed spacer 2 (ITS2) sequences analysed. In the hosts examined we identified D. capreolus, D. eckerti, D. filaria and D. viviparus. However, in fallow deer we detected a taxon with unique SSU and ITS2 sequences. The phylogenetic position of this taxon based on the SSU sequences shows that it is a separate evolutionary lineage from the other recognized species of Dictyocaulus. Furthermore, the analysis of the ITS2 sequence data indicates that it is as genetically distinct as are the named species of Dictyocaulus. Therefore, either this taxon needs to be recognized as a new species, or D. capreolus, D. eckerti and D. viviparus need to be combined into a single species. Traditionally, the genus Dictyocaulus has been placed as a separate family within the superfamily Trichostrongyloidea. The present molecular phylogenetic analyses support the placement as a separate family, but the current data do not support the placement of the Dictyocaulidae within the Trichostrongyloidea without a reassessment of the placement of the superfamily Strongyloidea. While D. eckerti has been regarded as the one and only lungworm species of cervids, this study showed that 4 host species including 3 members of Cervidae (moose, reindeer, red deer) and 1 Bovidae (musk ox) were infected with this parasite. Host ranges of D. viviparus (cattle), D. filaria (sheep) and D. capreolus (moose and roe deer) were more restricted. No clear pattern of co-evolution between the dictyocaulid taxa and their bovid and cervid hosts could be determined.

Animals↗

[Nomenclature of Strongylidae above the family group].

It is necessary to distinguish the three main evolutionary lines which presently constitute the Trichostrongyloidea. We propose to raise the following taxa of Strongylida as presented in the CIH keys (1974). Ancylostomatina for Diaphanocephaloidea and Ancylostomatoidea. Strongylina for Strongyloidea. Trichostrongylina for Trichostrongyloidea. Metastrongylina for Metastrongyloidea. The Trichostronglyina suborder includes three superfamilies: Trichostrongyloidea, Molineoidea superfam. nov. and Heligmosomoidea superfam. nov.

Animals↗

The molecular forms of acetylcholinesterase from Necator americanus (Nematoda), a hookworm parasite of the human intestine.

Necator americanus (Nematoda: Strongyloidea), a human hookworm parasite, is known to release considerable amounts of acetylcholinesterase (AChE) [Pritchard, D. I., Leggett K. V., Rogan, M. T., McKean, P. G. & Brown, A. (1991) Necator americanus secretory acetylcholinesterase and its purification from excretory/secretory products by affinity chromatography, Parasite Immunol. 13, 187-199]. The present study deals with AChE activity recovered in sequential somatic extracts, and excretory/secretory products, of the adult stage of the parasite. 97% of AChE was extractable in low-salt and high-salt detergent-free buffers, and only 3% was solubilised by a further extraction in the presence of Triton X-100. AChE in all three extracts was affected by the AChE inhibitors eserine, bis(4-allyldimethylammoniumphenyl)pentan-3-one dibromide and edrophonium chloride, but was resistant to the effects of tetramonoisopropylpyrophosphortetramide, a butyrylcholinesterase inhibitor. Sucrose density centrifugation revealed that AChE in all somatic extracts (low-salt, high-salt and detergent) resolved almost exclusively as a single peak between 6.9-7.5 S, while excretory/secretory products resolved at 8.2 S. These values are all compatible with dimers of catalytic subunits and no evidence was found for the presence of higher oligomers such as asymmetric forms. The only sample to show a shift in sedimentation following the inclusion of detergent (Triton X-100, Brij 96) in the gradient was a component of the detergent-soluble extract, indicating the existence of a minor amphiphilic form. In low-salt-soluble and high-salt-soluble extracts, AChE was solubilised as a hydrophilic globular form, probably a dimeric G2. The analysis of diisopropylfluorophosphate-labelled extracts by SDS/PAGE, and unlabelled extracts by immunoblotting using a polyvalent antiserum to N. americanus AChE, indicated that the AChE isolated in each extract was biochemically and immunologically similar. The banding patterns obtained were comparable to that seen when purified AChE was analysed by SDS/PAGE and immunoblotted. This suggests that the basic catalytic subunit has a mass of 66-70 kDa with the active site being located in a 30-kDa domain. All experimental data indicate the existence of only one AChE class in Necator homologous to AChE of class B from Caenorhabditis elegans. The solubility characteristics and globular nature of this hookworm AChE suggest that its major function is as an excretory or secretory product. This again raises the question of the true biological function of this 'non-cholinergenic' nematode secretion.

Acetylcholinesterase↗