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 109 records · Page 6Linked to original sources
PubMed1986

The distribution of inhibited early third stage Cyathostominae larvae in the large intestine of the horse.

The distribution of inhibited early third stage Cyathostominae larvae in different parts of the large intestine of the horse was studied in 20 Shetland ponies necropsied in autumn 1982, 1983 and 1984. The location of the larvae in the large intestinal wall was studied by histological examination of the intestines of the eight ponies from 1984. Inhibited larvae were located predominantly and more or less equally in the caecum and the ventral colon. Generally fewer early L3 were in the dorsal colon. In 1984 a considerable proportion (mean 17%, range 9.7-36.9%) of the inhibited larvae was found in the contents instead of in the mucosa of the large intestine, despite a housing period under helminth free conditions of 5 weeks. These larvae probably had been overlooked in 1982 and 1983. In sections cut from the intestinal wall most early L3 were found in the lamina propria. They were surrounded by a small fibrous capsule. Some were found in the lumen or epithelium of the Lieberkühn's crypts and a small proportion in the submucosa.

Animals↗
PubMed1979

Changes in worm burden, haematological and serological response in rats after single and multiple Angiostrongylus cantonensis infections.

Thirteen groups of rats were first sensitized with single or double doses of 5--30 third-stage larvae of Angiostrongylus cantonensis, followed by a challenge infection with 100 larvae at various periods after the primary infection. Seven other groups of rats receiving only the sensitizing infection served as the controls. In all the sensitized rats, a significantly (p less than 0.05) smaller mean number of adult worms was found established in the challenge infection as compared to the control. The frequency of the sensitizing dose and timing of the challenge infection appeared to influence the intensity of the host's response. There was no conclusive evidence to indicate that the immune response could retard the growth, development, or sex ratios of the worms established in subsequent infections. A positive haemagglutinating antibody response was first observed in some rats as early as four weeks post-infection with 100 larvae when the worms began migrating from the brain to the lungs. The antibody response and eosinophilia were most pronounced during the oviposition of the female worms and hatching of first-stage-larvae. Changes in white blood cell, lymphocyte, and neutrophil counts were also followed in some groups.

Animals↗
PubMed1984

In vitro induction of lymphocyte responsiveness by a Strongylus vulgaris-derived mitogen.

Proliferation in vitro of peripheral blood lymphocytes both from horses infected with Strongylus vulgaris and from helminth-free ponies was observed in the presence of extracts of the fourth and fifth stage larvae and adults of S. vulgaris. In addition, S. vulgaris extracts induced transformation in cultures of peripheral blood lymphocytes from sheep and dogs and in mouse spleen cell cultures. Nylon wool non-adherent, T cell enriched fractions of lymphocytes from both mice and horses were stimulated by the S. vulgaris larval mitogen while no proliferation was observed in cultures containing nylon wool adherent, B cell enriched fractions. Macrophage co-operation appeared not to be necessary for S. vulgaris mitogen-induced transformation of spleen cells. The S. vulgaris mitogen stimulated a subpopulation of mouse spleen cells different from those responsive to PHA, Con A and LPS. These cells might be T helper cells since B cells were stimulated to proliferate in the presence of both T cells and S. vulgaris larval mitogen. In addition, the supernatant of in vitro cultured larvae of S. vulgaris induced slight, but significant transformation of equine peripheral blood lymphocytes. Therefore, it is possible that the S. vulgaris mitogen released by both viable parasites and degenerating larvae might induce T cell dependent production of immunoglobulin in vivo and account for the beta-globulinaemia, of which IgG(T) is a major component, in S vulgaris infected horses.

Animals↗
PubMed1988

Effect of Strongyloides ratti on small bowel function in normal and immunosuppressed host rats.

Although Strongyloides stercoralis is a common parasite, little is known about its effect on intestinal function. Published clinical studies are difficult to evaluate and compare because of the inability to differentiate the effects of the parasite load from that of various other coexisting features such as bacterial overgrowth, multiparasitism, malnutrition, or tropical sprue. Using a rat model where these problems do not occur, we found that Strongyloides ratti did not inhibit intestinal function in the healthy rat. In fact, in normal rats S. ratti appeared to increase ileal sucrase activity. In contrast, in the methylprednisolone-treated rat, S. ratti produced a decrease in lactase and sucrase activity and an increase in alkaline phosphatase activity. S. ratti had no effect on 3-O-methylglucose uptake or D-xylose absorption in either group. These results suggest that S. ratti has little effect on small bowel function in a healthy rat but can cause minor alterations in intestinal function in an immunosuppressed, methylprednisolone-treated, malnourished host. These results are also consistent with clinical observations seen with S. stercoralis in humans and with another nematode, Ascaris suus, in the pig model.

Alkaline Phosphatase↗
PubMed1981

Epidemiology of Strongylus vulgaris infection of the horse in Morocco.

Between August 1978 and July 1979 the anterior mesenteric artery and its branches were collected regularly from adult horses and examined for Strongylus vulgaris larvae. The incidence of infection varied from 55 to 100% (annual mean 80%). The mean monthly number of larvae ranged form 3 to 22 with an annual overall mean of 13. The arterial infection was at its minimum in December to January, rose gradually to attain the peak in June and declined thereafter. These observations indicated that S. vulgaris is an annual species in Morocco, infection occurring during the rainy season (November-April), the heavy arterial population in spring and adult population during autumn and winter.

Animals↗
PubMed1984

Internal parasitism in milk goats in Kenya.

Observations were made on individual cases and on herds showing the effects of internal parasitism on the health and productivity of Toggenberg and Saanan goats. The clinical reactions varied markedly being influenced by the degree of infestation and duration of illness. Typical cases showed emaciation, anaemia, oedema, weakness and sometimes diarrhoea and death. Faecal analyses were dominated by strongyle egg counts which rose progressively throughout the study period. Overstocking led to some animals being at greater risk.

Animals↗
PubMed2004

Microchip capillary electrophoresis-based genetic comparison of closely related cyathostomin nematode parasites of horses using randomly amplified polymorphic DNA polymerase chain reaction.

The microchip-based capillary electrophoresis technology represents a valuable recent development for the analysis of complex DNA banding patterns. We have used this technology for the differentiation of the closely related cyathostomin species Cylicocyclus elongatus and C. insigne from the horse. We found that the Agilent 2100 bioanalyser in combination with the DNA 7500 Lab Chip were suited to perform a phylogenetic DNA fingerprinting analysis of the parasite species studied. The analysis of the electrophoretic data was optimised and it was possible to resolve a phylogenetic tree where all 12 individual worms of the two Cylicocyclus species studied were assigned to their species as determined by microscopic identification based on morphological traits. Thus, our data indicated that the procedure described here provides an additional powerful tool that can be employed for species delineation of closely related strains or species, such as the two taxa of Cylicocyclus investigated in the present study. Furthermore, by determining the second internal transcribed spacer region of three and nine individual worms for C. elongatus and C. insigne, respectively, low intraspecific variations of only up to 0.3% were demonstrated.

Animals↗
PubMed2004

Prevalence of parasite eggs (Strongyloides westeri, Parascaris equorum, and strongyles) and oocysts (Emeria leuckarti) in the feces of Thoroughbred foals on 14 farms in central Kentucky in 2003.

Prevalence of internal parasites was determined by fecal examination for eggs and oocysts in Thoroughbred foals in central Kentucky in 2003. Fecal samples were examined from 733 foals on 14 farms. This included 70 trips to the farms and a total of 2,346 fecal samplings. Monthly collection of fecal samples was begun for four farms in February, six in March, three in April, and one farm in May. Termination of the study for all farms was the end of July. A criterion was that the foals be at least 10 days old for initial samplings. If available, the same foals were sampled each time, in addition to foals born in the interim between farm visits. Ages of the foals for the complete study varied from 10 to 223 days. Prevalence (mean %) was determined for eggs of Strongyloides westeri (1.5%), Parascaris equorum (22.4%), and strongyles (27.6%) and for oocysts of Eimeria leuckarti (41.6%) in feces of foals. Foals had infections of S. westeri on six farms (42.9%), of P. equorum on 12 farms (86%), and of strongyles and E. leuckarti on all 14 farms (100%).

Animals↗
PubMed2004

Benzimidazole resistance in cyathostomin populations on horse farms in western Anatolia, Turkey.

A cross-sectional survey was performed on ten stud farms in western Anatolia, Turkey, in order to provide the first information on the problem of anthelmintic resistance in equine strongyles in this country. Benzimidazole (BZ) resistant cyathostomin populations were detected on seven farms if pre- and post-treatment egg counts are compared in treated animals and the resistance is defined as a mean faecal egg count reduction (FECR) of <95% with a lower 95% confidence limit of <90%. Egg hatch tests using an ED(50) of 0.1 microg/ml thiabendazole as the cut-off value confirmed BZ resistance on four of the seven farms. The probable reasons for the occurrence of BZ resistance are discussed. Resistance to pyrantel embonate or macrocyclic lactones, evaluated on five and six farms, respectively, was not detected using the FECR test.

Animals↗
PubMed2005

Identification of strongyle eggs from anthelmintic-treated horses using a PCR-ELISA based on intergenic DNA sequences.

The efficacy of five daily fenbendazole (FBZ) treatments was tested against benzimidazole-resistant cyathostomins in naturally infected horses (n=13). Horses were treated with pyrantel embonate (PYR) to remove adult strongyles followed, 7 days later, by a 5-day course of FBZ. The PYR treatment produced an average faecal egg count reduction of 98%. All samples were negative by faecal egg count 7 days after the start of the FBZ treatment. Positive egg counts were observed from 28 days after the start of FBZ treatment and all horses displayed positive faecal egg counts by 77 days after treatment. Strongyle eggs were harvested from the faeces of the horses prior to treatment and then weekly from 42 to 70 days post-treatment. DNA was obtained from eggs in groups of ten. A PCR-ELISA, based on species-specific differences in intergenic DNA sequences, was used to identify the presence of six cyathostomin species. In pre-treatment samples, Cyathostomum catinatum was detected in nine out of the 13 horses and Cylicostephanus longibursatus, Cylicostephanus goldi and Cylicocyclus nassatus, were found in samples from eight animals. Cylicocyclus ashworthi and Cylicocyclus insigne were not detected pre-treatment. After anthelmintic treatment, C. catinatum and C. longibursatus were most frequently detected, followed by C. nassatus, C. goldi and C. ashworthi. C. insigne was detected at only one time point in a sample from a single horse.

Animals↗
PubMed2006

Expression of recombinant beta-tubulin alleles from Cylicocyclus nassatus (Cyathostominae).

Small strongyles (Cyathostominae) are common nematode parasites of horses that have developed resistance to the benzimidazole anthelmintics used to control their populations. Evidence suggests that the principal mechanism of resistance involves a phenylalanine-to-tyrosine mutation at codon 200 in the beta-tubulin proteins that are components of microtubules. Other works, however, suggest that a phenylalanine-to-tyrosine mutation at codon 167, or alternative mechanisms, may be involved. As part of an ongoing project examining the role that these two beta-tubulin mutations may play in benzimidazole resistance, we have cloned the wild-type allele and the two alleles with the phenylalanine-to-tyrosine mutations at codons 167 and 200 of the beta-tubulin isotype 1 gene from the small strongyle Cylicocyclus nassatus. In this work, we describe the construction of expression vectors containing these alleles and their expression in Escherichia coli.

Alleles↗
PubMed1999

Characterization of Chabertia ovina by isoenzyme gel electrophoresis: comparative study with Oesophagostomum venulosum.

The glucose-6-phosphate dehydrogenase (G6PD, EC.1.1.1.49), glucose phosphate isomerase (GPI, EC.5.3.1.9), and malate dehydrogenase (MDH, EC.1.1.1.37) isoenzymatic patterns of Chabertia ovina were determined by starch-gel electrophoresis. The G6PD and GPI isoenzymatic patterns were characterized by the existence of three phenotypes: (1) a single and slow anodic band, (2) a single and fast anodic band, and (3) a large spot matching its migration with bands 1 and 2. These three phenotypes may be explained as the existence of only one gene locus for the G6PD and GPI in C. ovina. Allelic frequencies and the Hardy-Weinberg test were determined. This test indicated that the population was not in Hardy-Weinberg equilibrium. The MDH isoenzymatic pattern of C. ovina was characterized by the presence of two bands with anodic and cathodic migration. Furthermore, comparative isoenzyme studies were carried out between Oesophagostomum venulosum and C. ovina. The different G6PD, GPI, and MDH isoenzymatic patterns observed for the two species allowed us to distinguish them and, therefore, to use isoenzymatic patterns as a diagnostic tool to discriminate these species.

Animals↗