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molecular identification of cryptic cysticercosis: taenia ovis krabbei in wild intermediate and domestic definitive hosts.the complex life cycle of taeniids represents an ideal model of a multi-host system. the complexity of these parasites can therefore cover the epidemiological issues of the interface between wild and domestic animals, especially once spatial overlap between wild and domestic definitive and intermediate hosts occurs. here we use the occurrence of taenia ovis krabbei in two model areas as an example of this epidemiological complexity. in two contiguous areas in the italian northern apennines, two ...201728349853
high-throughput identification of mirnas of taenia ovis, a cestode threatening sheep industry.taenia ovis is a tapeworm that is mainly transmitted between dogs and sheep or goats and has an adverse effect on sheep industry. mirnas are short regulatory non-coding rnas, involved in parasite development and growth as well as parasite infection. the mirna profile of t. ovis remains to be established. herein, 33 known mirnas belonging to 23 different families were identified in t. ovis metacestodes using deep sequencing approach. of them, expression of some mirnas such as tov-mir-10 and -let- ...201728342885
proteomic analysis of taenia ovis metacestodes by high performance liquid chromatography-coupled tandem mass spectrometry.taenia ovis metacestodes reside in the muscle of sheep and goats, and may cause great economic loss due to condemnation of carcasses if not effectively controlled. although advances have been made in the control of t. ovis infection, our knowledge of t. ovis biology is limited. herein the protein profiling of t. ovis metacestodes was determined by liquid chromatography-linked tandem mass spectrometry. a total of 966 proteins were identified and 25.1% (188/748) were annotated to be associated wit ...201728288753
evaluation of microsatellites markers to discriminate four main taeniid tapeworms of dogs.echinococcus granulosus, taenia multiceps, taenia ovis and taenia hydatigena are among the most prevalent taeniid species of dogs. these tapeworms infect ruminant and humans as intermediate hosts and domestic/wild carnivores as the definitive hosts. molecular tools using hypervariable microsatellite regions might provide more information about parasite variation. highly variable and specific tools are needed for transmission tracking studies of canine echinococcosis as an essential element for i ...201728761491
prevalence and pathological lesions of ovine cysticercosis in slaughtered sheep in western iran.cysticercusovis, the intermediate stage of a canine tapeworm, taenia ovis, produces cystic lesions in the skeletal and cardiac muscle of sheep which, if numerous, will result in the condemnation of an entire carcass. this study was carried out between march 2013 and march 2014 to estimate the prevalence of taenia oviscysticercosis in sheep slaughtered at the kermanshah municipal abattoir, in western iran. of 69,198 sheep examined, 833 (1.27 %) were infected with cysticerci of taenia ovis. the pr ...201627876986
the first outbreak of taenia ovis infection in china.infection of taenia ovis metacestodes in sheep or goats causes great economic losses due to condemnation of carcasses. t. ovis infection is not formally recorded in china to date. in october, 2015, t. ovis infection occurred in jingtai county, china, and 113 of 192 sheep from one farm were infected. cysts resided in the cardiac and skeletal muscle, and evaginated metacestodes had four suckers and scolex armed with approximately 23 hooks. using cox1 and nad1 as molecular markers, the sample was f ...201627276429
detection of taeniid (taenia spp., echinococcus spp.) eggs contaminating vegetables and fruits sold in european markets and the risk for metacestode infections in captive primates.due to frequent cases of alveolar echinococcosis (ae) in captive primates in europe, 141 samples of food, which consisting of vegetables and fruits, were investigated for contamination with egg-dna of taeniids. each sample consisted of at least 40 heads of lettuce as well as various vegetables and fruits. the samples were purchased at different times of the year: either from september to november (autumn), originating from greenhouses or fields in the basel region in the north of switzerland, or ...201627556010
taenia ovis: an emerging threat to the chinese sheep industry?taenia ovis is a tapeworm that is mainly transmitted between dogs and sheep. although t. ovis infection is not a public health issue, it causes a great financial loss due to condemnation of carcasses.  the first outbreak of t. ovis infection in china occurred in 2015. reassessment of adverse effects of t. ovis infection on chinese sheep industry in future is necessary.201627460570
systematic review and meta-analysis of metacestodes prevalence in small ruminants in ethiopia.metacestodes, the larval stages of canid cestode parasites, are among the causes of morbidity, mortality and financial losses in small ruminants in ethiopia as a result of organ and carcass condemnation at slaughter. several studies have been conducted over the years; however, these studies often had limited scope and coverage. this systematic review and meta-analysis was conducted to collate the information so far available in order to provide a pooled prevalence estimate at national level and ...201627317327
high-resolution melting analysis (hrm) for differentiation of four major taeniidae species in dogs taenia hydatigena, taenia multiceps, taenia ovis, and echinococcus granulosus sensu stricto.tapeworms of the genus taenia include several species of important parasites with considerable medical and veterinary significance. accurate identification of these species in dogs is the prerequisite of any prevention and control program. here, we have applied an efficient method for differentiating four major taeniid species in dogs, i.e., taenia hydatigena, t. multiceps, t. ovis, and echinococcus granulosus sensu stricto. high-resolution melting (hrm) analysis is simpler, less expensive, and ...201627008188
the occurrence of taeniids of wolves in liguria (northern italy).canids are definitive hosts of taenia and echinococcus species, which infect a variety of mammals as intermediate or accidental hosts including humans. parasite transmission is based on domestic, semi-domestic and wildlife cycles; however, little is known of the epidemiological significance of wild large definitive hosts such as the wolf. in this study, 179 scats of wolves (canis lupus italicus) collected throughout the italian region of liguria were analyzed for the detection of taeniid infecti ...201526042204
an epidemiological survey on intestinal helminths of stray dogs in mashhad, north-east of iran.this research was conducted to determine the prevalence of gastrointestinal helminths in stray dogs in the northeast of iran, with special attention to those parasites that can be transmitted to human. in this experiment, a total of 72 adult and 18 juvenile stray dogs were collected and necropsied for the presence of helminth parasites from october 2011 to august 2012. the overall prevalence of gastrointestinal helminths was 86 % (95 % ci: 79.2-92.8 %). the observed helminths of the gastrointest ...201526064015
molecular identification of species of taenia causing bovine cysticercosis in ethiopia.bovine cysticercosis causing damage to the beef industry is closely linked to human taeniasis due to taenia saginata. in african countries, taenia spp. from wildlife are also involved as possible sources of infections in livestock. to identify the aetiological agents of bovine cysticercosis in ethiopia, cysticerci were collected from 41 cattle slaughtered in the eastern and central areas during 2010-2012. a single cysticercus per animal was subjected to the polymerase chain reaction (pcr)-based ...201423452760
taenia ovis infection and its control: a canadian perspective.distributed worldwide, taenia ovis infection is responsible for the condemnation of sheep carcasses in many countries. this review highlights the programme used in new zealand to successfully control t. ovis in sheep, and discusses how similar approaches may be modified for use in canada, given what is currently known about the epidemiology of t. ovis. the lifecycle of the parasite is well known, involving dogs as the definitive host and sheep or goats as the intermediate host. an effective vacc ...201424053136
red foxes (vulpes vulpes) and wild dogs (dingoes (canis lupus dingo) and dingo/domestic dog hybrids), as sylvatic hosts for australian taenia hydatigena and taenia ovis.foxes (n = 499), shot during vertebrate pest control programs, were collected in various sites in the australian capital territory (act), new south wales (nsw) and western australia (wa). wild dogs (dingoes (canis lupus dingo) and their hybrids with domestic dogs) (n = 52) captured also as part of vertebrate pest control programs were collected from several sites in the act and nsw. the intestine from each fox and wild dog was collected, and all taenia tapeworms identified morphologically were c ...201425161904
[major host-protective antigens of taeniidae cestode and their molecular biological characteristics].taeniidae cestodes are the pathogens of cysticercosis and hydatid disease, these diseases lead to substantial economic losses in animal husbandry and cause morbidity and mortality in human population. in recent years, many host-protective antigens of taeniidae cestodes has been found, and their recombinant protein vaccines have been developed against several species, such as taenia ovis, t. saginata, t. solium, echinococcus granulosus, and e. multilocularis. this paper focuses on the major host- ...201425902683
immunodiagnosis of sheep infections with echinococcus granulosus: in 35 years where have we come?w. k. yong and d. d. heath published in 1979 a seminal paper in the first issue of parasite immunology describing their efforts to determine whether the arc 5 precipitin band, formed when test human serum is reacted against electrophoresed hydatid cyst fluid antigen, would be a suitable immunodiagnostic test for the identification of sheep infected with echinococcus granulosus. although they found antibodies to arc 5 in the sera of hydatid-infected sheep, the sera of some sheep harbouring taenia ...201424033483
development of a taenia ovis transmission model and an assessment of control strategies.the metacestode stage of the tapeworm, taenia ovis, causes cystic lesions in the skeletal and cardiac muscle of sheep, which can result in the condemnation of the entire carcass. in recent years, canadian farms have seen a marked increase in the number of condemnations due to t. ovis. mathematical transmission models provide a useful tool for predicting parasite transmission and for evaluating the efficacy of potential control options. to date, no model has been developed exclusively for t. ovis ...201323993638
environmental conditions predict helminth prevalence in red foxes in western australia.red foxes (vulpes vulpes) are the most common and widely distributed wild carnivore worldwide. these predators harbour a wide range of parasites, many of which may have important conservation, agricultural and zoonotic repercussions. this project investigated the occurrence of helminth parasites from the intestines of 147 red foxes across 14 sampling localities of southwest western australia. helminth parasites were detected in 58% of fox intestines: dipylidium caninum (27.7% of foxes), uncinari ...201324533331
seasonal and biogeographical patterns of gastrointestinal parasites in large carnivores: wolves in a coastal archipelago.parasites are increasingly recognized for their profound influences on individual, population and ecosystem health. we provide the first report of gastrointestinal parasites in gray wolves from the central and north coasts of british columbia, canada. across 60 000 km(2), wolf feces were collected from 34 packs in 2005-2008. at a smaller spatial scale (3300 km(2)), 8 packs were sampled in spring and autumn. parasite eggs, larvae, and cysts were identified using standard flotation techniques and ...201222309976
distribution of, and risk factors associated with, sheep carcass condemnations due to cysticercus ovis infection on canadian sheep farms.cysticercus ovis, the intermediate stage of a canine tapeworm, taenia ovis, produces cystic lesions in the skeletal and cardiac muscle of sheep which, if numerous, will result in the condemnation of an entire carcass. in 2007 and 2008, the number of carcass condemnations due to c. ovis rose dramatically across canada, suggesting that the prevalence of this infection on sheep farms was increasing. trace-back of 237 carcasses condemned at ontario provincially inspected abattoirs, between march 200 ...201222877826
reappearance of taenia ovis krabbei muscle cysts in a roe deer (capreolus capreolus) in denmark after 60+ years.the present report describes the reappearance of taenia ovis krabbei in a roe deer from denmark after more than 60 years. the cysticerci were isolated from the thigh muscle of the deer, and the diagnosis was based on histostological analysis, morphology of the rostellar-hooks as well as molecular typing of the mitochondrial cytochrome c oxidase i (cox1) gene. the exact definitive host was not revealed in this report, but domestic dogs may play a role of the definitive host in the area. this find ...201223298567
severe taenia ovis outbreak in a sheep flock in south-west england. 201121642295
first record of taenia ovis krabbei muscle cysts in muskoxen from greenland.a first record of taenia ovis krabbei muscle cysts in a muskoxen (ovibos moschatus) from the kangerlussuaq population in west greenland suggests that introduced muskoxen now contributes to the transmission of this parasite in addition to previous observations from caribou (rangifer tarandus). muskoxen and caribou are the only wild ungulates in greenland.201121955737
seroepidemiological survey of helminthic parasites of stray dogs in sari city, northern iran.the objective of this study was to determine the prevalence rate of helminthic parasites in stray dogs' population especially zoonotic infections and to identify potential risk factors in the different areas of sari city in caspian area, north of iran. during the period from april to september 2007, 50 stray dogs were collected from urban areas of sari city. recovered parasites were fixed in alcohol and stained by carmine then observed by microscope. the taxonomic study was carried out by measur ...201121916265
ultrastructural reconstruction of taenia ovis oncospheres from serial sections.the cellular organisation of taenia ovis oncospheres is interpreted from ultrathin serial sections and transmission electron microscopy following high pressure freezing and freeze-substitution. the surface of a hatched, non-activated t. ovis oncosphere is covered by an oncospheral membrane below which is the tegument bearing microvilli. the basal lamina of the tegument is underlain by broad bands of peripheral somatic musculature. three pairs of hooks and associated muscles are present in the so ...201020478311
oncospheral penetration glands and secretory blebs are the sources of taenia ovis vaccine antigens.taenia ovis is a cestode parasite infecting primarily sheep as intermediate hosts and dogs as definitive hosts. the first highly effective, recombinant vaccine against a parasitic organism was developed against t. ovis infection in sheep. three separate host-protective antigens (to16, to18, and to45w) have been cloned from the oncosphere of the parasite. we localize these antigens in the oncosphere by using quantitative immunogold labeling and transmission electron microscopy. the three antigens ...201020643854
the ultrastructure of taeniid cestode oncospheres and localization of host-protective antigens.taeniid eggs contain an infective larval form of the parasite, known as the oncosphere, which has been found to be highly susceptible to attack by the host's immune system and this fact has been exploited in the development of highly effective vaccines. relatively little is known about the structure of taeniid oncospheres and the localization of host-protective antigens within or on the oncosphere. here, we briefly review the current state of knowledge of the structure of the oncosphere and pres ...201019835645
localisation of three host-protective oncospheral antigens of taenia ovis.immunohistochemistry, confocal immunofluorescence and immunogold labelling were used to determine the localisation of the host-protective antigens to16, to18 and to45w in taenia ovis oncospheres. during maturation of the adult tapeworm the antigens were initially seen as diffuse staining in the developing oncospheres but in mature oncospheres four distinct cells stained positively for the antigens. confocal fluorescence microscopy using different fluorophores revealed that each of the antigens c ...201019883651
endoparasites of the coyote (canis latrans), a recent migrant to insular newfoundland.this study provides the first data on the helminth fauna of the coyote (canis latrans) in insular newfoundland. sixty-nine coyotes were collected between 2001 and 2003 and examined for helminths. a total of 10 helminth species were recorded: the cestodes taenia ovis krabbei (9%), taenia hydatigena (4%), taenia pisiformis (1%), and mesocestoides spp. (5%); and the nematodes toxocara canis (19%), toxascaris leonina (1%), crenosoma vulpis (19%), physaloptera rara (6%), uncinaria stenocephala (3%), ...200919901402
helminth parasites of the wolf canis lupus from latvia.thirty-four wolves were collected between 2003 and 2008 from throughout latvia and examined for helminths. a total of 17 helminth species were recorded: the trematode alaria alata (85.3%); the cestodes diphyllobothrium latum (2.9%), echinococcus granulosus (2.9%), echinococcus multilocularis (5.9%), mesocestoides lineatus (5.9%), taenia crassiceps (8.8%), taenia hydatigena (41.2%), taenia (ovis) krabbei (8.8%), taenia multiceps (47.1%), taenia pisiformis (20.6%), taenia polyacantha (11.8%), taen ...200919138449
vaccination with recombinant oncosphere antigens reduces the susceptibility of sheep to infection with taenia multiceps.taenia multiceps is a cestode parasite, the larval stage of which encysts in the brain of sheep, goats and cattle causing an often fatal condition. the parasite also causes zoonotic infections in humans. homologues of the recombinant oncosphere vaccine antigens from taenia ovis and other taenia species were identified in t. multiceps. sequencing of the associated t. multiceps genes and cloning of the encoding mrna has revealed conserved features in the genes and proteins. the t. multiceps oncosp ...200818160069
prevalence and seasonal incidence of larval and adult cestode infections of sheep and goats in eastern ethiopia.a study on the prevalence and seasonal incidence of cestode parasite infections of sheep and goats was carried out in eastern ethiopia for 2 years (may 2003-april 2005). during this period, viscera including liver, lungs, heart, kidneys and the gastro-intestinal tract were collected from 655 sheep and 632 goats slaughtered at four abattoirs located in the towns of haramaya, harar, dire dawa and jijiga. at the abattoirs the abdominal, thoracic and pelvic cavities as well as the muscle surfaces of ...200818575964
a phylogeny of members of the family taeniidae based on the mitochondrial cox1 and nad1 gene data.the cestode family taeniidae consists of 2 genera, taenia and echinococcus, which both have been the focus of intensive taxonomic and epidemiological studies because of their zoonotic importance. however, a comprehensive molecular phylogeny of this family has yet to be reconstructed. in this study, 54 isolates representing 9 taenia species were characterized using dna sequences in the mitochondrial cytochrome c oxidase subunit 1 (cox1) and nadh dehydrogenase subunit 1 (nad1) genes. phylogenetic ...200818937885
molecular and functional characterization of a taenia adhesion gene family (taf) encoding potential protective antigens of taenia saginata oncospheres.two clones from an activated taenia saginata oncosphere cdna library, ts45w and ts45s, were isolated and sequenced. both of these genes belong to the taenia ovis 45w gene family. the ts45w and ts45s cdnas are 997- and 1,004-bp-long, each corresponding to 255 amino acids and with theoretical molecular masses of 27.8 and 27.7 kda, respectively. southern blot profiles obtained with ts45w cdna as a probe suggest that these two genes are members of a multigene family with tandem organization. the ful ...200717048003
cestode vaccines: origins, current status and future prospects.recombinant vaccines have been developed which are highly effective in preventing infection with taenia ovis in sheep, taenia saginata in cattle, taenia solium in pigs and echinococcus granulosus in livestock animals. t. ovis and t. saginata are economically significant parasites and the commercial success or otherwise of vaccines against them will rely on their economic value. e. granulosus and t. solium are zoonotic parasites that cause cystic hydatid disease and neurocysticercosis, respective ...200617274847
potential existence of a sylvatic cycle of taenia ovis krabbei in patagonia, argentina.red deer (cervus elaphus) were introduced in southern latin america about a century ago and characteristics of the invasion raise concerns over their epidemiological role for various diseases. we report on the possible occurrence of taenia ovis krabbei established in a sylvatic cycle in patagonia. hook characters, size, appearance, and location of a cysticercus from a wild red deer are consistent with taenia ovis ovis or t. o. krabbei. although it is not possible to differentiate between t. o. o ...200616289565
vaccines against cysticercosis and hydatidosis: foundations in taeniid cestode immunology.recombinant oncosphere antigens have been used in the development of effective vaccines for the prevention of cysticercosis caused by taenia ovis, taenia saginata, taenia solium and hydatid disease caused by echinococcus granulosus. these vaccines were developed utilizing information gathered from numerous researchers over some 60 years which had established many of the principals concerning immunity to taeniid cestodes in their intermediate hosts. australian scientists, or scientists with close ...200616337177
detection of echinococcus granulosus coproantigens in faeces from naturally infected rural domestic dogs in south eastern australia.to investigate the occurrence of echinococcus granulosus in rural domestic dogs in farming areas around yass, new south wales, and mansfield and whitfield, victoria.200616498828
taenia solium and taenia ovis: stage-specific expression of the vaccine antigen genes, tsol18, tsol16, and homologues, in oncospheres.recombinant antigens that have been cloned from taenia solium and taenia ovis have been shown to be highly effective when used as vaccines against cysticercosis in the intermediate hosts. this study investigated the presence of mrna encoding the tsol18 and tsol16 antigens in different life-cycle stages of t. solium, and their related homologues in t. ovis. reverse transcription-pcr and southern blotting demonstrated that the antigens are stage-specifically expressed in the oncosphere. the appare ...200616510142
in vitro oncosphere-killing assays to determine immunity to the larvae of taenia pisiformis, taenia ovis, taenia saginata, and taenia solium.taeniid cestodes infect humans and livestock, causing considerable morbidity and mortality, as well as economic loss. substantial progress has been made toward the production of recombinant vaccines against cysticercosis in livestock animals. further development of these vaccines would be aided if a reliable in vitro test were available to measure host-protective immune responses in vaccinated animals. here, we describe in vitro oncosphere-killing assays for the quantification of host-protective ...200616729683
helminthologic survey of the wolf (canis lupus) in estonia, with an emphasis on echinococcus granulosus.carcasses of 26 wolves were collected during the 2000/2001 and 2003/2004 hunting seasons and examined for helminths. thirteen helminth species were recorded: one trematode (alaria alata), seven cestodes (diphyllobothrium latum, mesocestoides lineatus, taenia hydatigena, taenia multiceps, taenia ovis, taenia pisiformis, and echinococcus granulosus), and five nematode species (uncinaria stenocephala, toxascaris leonina, toxocara canis, trichinella nativa, and trichinella britovi). the most common ...200616870858
a study on intestinal helminthes of dogs, foxes and jackals in the western part of iran.human infection especially with helminth parasites is an emerging health issue, as the human environment is increasingly shared with infected animals, either pets or wild life. in this survey, the intestinal content of 83 stray dogs, 22 red foxes and 10 golden jackals collected from the west azarbaijan, kordestan and kermanshah provinces in the west of iran, were studied for the presence of helminth parasites. the percentage of different species recovered from these animals is listed as follows: ...200616899340
local and systemic immune responses to echinococcus granulosus in experimentally infected dogs.local and systemic immune responses were studied in six dogs experimentally infected with the dog/sheep tapeworm echinococcus granulosus. all dogs developed similar igg antibody response to parasite antigens. in contrast, ige and iga responses differed widely. no relationship between iga responses and parasite burden at the end of the infection were observed. further, clear differences in the anti-parasite iga response in serum as compared with specific iga forming cells in mesenteric lymph node ...200415036575
national prevalence of larval echinococcosis in sheep in slaughtering plants ovis aries as an indicator in control programmes in uruguay.diagnostic surveys carried out on ovine larval echinococcosis in slaughtering plants at a national level in 1998 made it possible to meet several objectives, i.e. to estimate the existing levels of prevalence, to evaluate the effectiveness of the control actions applied by the programme against hydatidosis and to contribute to the improvement of the health information systems for epidemiological surveillance. the work included sheep (ovis aries), both lambs (2-4 teeth) and adults (6-8 teeth). a ...200312606107
molecular cloning of genes encoding oncosphere proteins reveals conservation of modular protein structure in cestode antigens.recombinant oncosphere antigens have been found to be remarkably effective when used as vaccines against cysticercosis and hydatid disease. comparison of the structural features of these proteins and their associated genes suggest common features between antigens. here molecular cloning is used to complete comparisons of taenia solium, taenia saginata, taenia ovis, echinococcus granulosus and echinococcus multilocularis oncosphere antigens and genes. the exon/intron structure of genes cloned fro ...200312672528
vaccines for prevention of cysticercosis.neurocysticercosis due to taenia solium infection is an important cause of human morbidity and mortality. despite the availability of effective anthelmintics, the disease remains prevalent in many parts of the world and there is a need for new and improved measures for control of the infection. an effective vaccine to prevent infection in pigs, the parasite's natural intermediate host, would be a valuable new option to assist with t. solium control. several approaches are being used currently to ...200312781387
vaccination against cestode parasites: anti-helminth vaccines that work and why.highly effective recombinant vaccines have been developed against the helminth parasites taenia ovis, taenia saginata and echinococcus granulosus. these vaccines indicate that it is possible to achieve a reliable, high level of protection against a complex metazoan parasite using defined recombinant antigens. however, the effectiveness of the vaccines against the taeniid cestodes stands in contrast to the more limited successes which characterise attempts to develop vaccines against other platyh ...200312878418
molecular and genetic characterisation of the host-protective oncosphere antigens of taeniid cestode parasites.highly effective recombinant vaccines have been developed against taenia ovis infection in sheep, taenia saginata infection in cattle, taenia solium infection in pigs, echinococcus granulosus and echinococcus multilocularis infections in a variety of intermediate host species. these vaccines have been based on the identification and expression in escherichia coli of antigens derived from the oncosphere life cycle stage, contained within the parasites' eggs. investigation of the molecular aspects ...200313678636
alternative splicing and sequence diversity of transcripts from the oncosphere stage of taenia solium with homology to the 45w antigen of taenia ovis.genes and transcripts which show homology to the host-protective 45w antigen of taenia ovis have been cloned from the human parasite taenia solium. the t. solium genes cloned in this study (tso45) show conserved genomic structural features which are also features of the t. ovis 45w gene family. the tso45 genes consist of a four exon and three intron structure. eight tso45 transcripts, encoded by at least five genes, were cloned from t. solium oncospheres and comparison of their dna sequence indi ...200111223124
parasitic vaccines: an utopia or reality?major advances in biotechnology over the past decade have led to significant progress in antigen selection, recombinant protein production and antigen delivery in a number of host-parasite systems. vaccination against complex metazoan parasites has become a reality with the development of recombinant vaccines against the cattle tick boophilus microplus and the sheep cestode taenia ovis. in the present paper progress towards the development of similar vaccines against other parasites is discussed ...200111284387
the human igg3 hinge mediates the formation of antigen dimers that enhance humoral immune responses to dna immunisation.a series of plasmid dna constructs containing the 45w antigen gene from taenia ovis were used to investigate the impact of antigen dimerisation on the humoral immune response to genetic immunisation. genes encoding dimeric 45w were generated via fusion to the hinge region of human igg3 (hig). this region was selected because it is compact and contains 11 inter-chain disulphide-bridges. the dna encoding the igg3 hinge contains four exons, with the last three exons being repeats and possibly super ...200111457535
the comparative efficacy of ctla-4 and l-selectin targeted dna vaccines in mice and sheep.the access of antigens to antigen presenting cells (apcs) appears to be a rate-limiting step in the generation of immune responses to dna vaccines. the cytotoxic t lymphocyte antigen 4 (ctla-4) and l-selectin represent attractive ligands for use in the targeting of antigen to apcs and lymph nodes. ctla-4 binds with high affinity to the b7 membrane antigen on apcs, while l-selectin functions as a lymphocyte homing marker and binds to cd34 on the surface of high endothelial venule cells. dna vacci ...200111483267
parasite vaccines--a reality?over the last decade, the anti-parasitics market has been the fastest growing sector of the overall $18 billion animal health market. while drugs for the treatment of parasites of livestock still dominate this sector and will continue to be developed or re-formulated, because of consumer demands for chemical-free food and of concerns regarding the environment and animal welfare there is a growing interest in the development of safe and effective vaccines. there is also a call for vaccines in the ...200111516584
vaccines against cysticercosis and hydatidosis.the recombinant vaccines that have been developed against cysticercosis and hydatidosis in sheep and cattle are remarkable for their effectiveness and are prominent as examples of the very few non-living vaccines against parasitic diseases. their development has been through practical application of molecular parasitology, utilising immunochemical techniques in antigen identification and recombinant dna methods in antigen production. this brief overview discusses the contribution of molecular te ...200111707305
humoral immune responses to dna vaccines expressing secreted, membrane bound and non-secreted forms of the tania ovis 45w antigen.the antibody response to dna vaccines expressing secreted, membrane bound and non-secreted forms of the same antigen was investigated. the antigen gene selected for these studies was the full length 45w antigen gene from taenia ovis. this gene encodes a host protective membrane bound antigen with a native secretion signal at the amino terminus and a hydrophobic anchor domain at the carboxyl terminus. full length and rationally truncated forms of the 45w antigen gene were generated and used to co ...200010775786
development of vaccines against gastrointestinal nematodes.vaccination against complex metazoan parasites has become a reality with the development and registration of recombinant protein-based vaccines against the cattle tick boophilus microplus and the sheep cestode taenia ovis. progress towards the development of similar vaccines against gastrointestinal nematodes, primarily of ruminants, is outlined within a framework of defining the practical requirements for successful vaccination, antigen selection, recombinant protein production and antigen deli ...200010874709
a comparison of dna vaccines expressing the 45w, 18k and 16k host-protective antigens of taenia ovis in mice and sheep.the immunogenicity of dna vaccines encoding three different taenia ovis host-protective antigens was compared in mice and sheep. dna vaccines encoding the 45w, 18k and 16k antigens of t. ovis were constructed. the ability of dna vaccines encoding the 45w and 18k genes to express antigen was confirmed by western blotting of transfected cos-7 cells. balb/c mice were vaccinated intramuscularly with 45w, 18k or 16k dna vaccines and the humoral immune response analysed by elisa. dna vaccines expressi ...200011044551
nadh dehydrogenase subunit 1 and cytochrome c oxidase subunit i sequences compared for members of the genus taenia (cestoda).nine members of the genus taenia (taenia taeniaeformis, taenia hydatigena, taenia pisiformis, taenia ovis, taenia multiceps, taenia serialis, taenia saginata, taenia solium and the asian taenia) were characterised by their mitochondrial nadh dehydrogenase subunit 1 gene sequences and their genetic relationships were compared with those derived from the cytochrome c oxidase subunit 1 sequence data. the extent of inter-taxon sequence difference in nadh dehydrogenase subunit 1 (approximately 5.9-30 ...199910961852
synthetic peptide antigens induce antibodies to taenia ovis oncospheres.sheep immunised with the taenia ovis recombinant 45w antigen are protected from infection with the parasite. two peptides were synthesised corresponding to putative host-protective regions at the n- and c-termini of 45w. sera from sheep immunised with 45w or related recombinant proteins reacted strongly with the n-terminal peptide. approximately 40% of the antibody directed against 45wb/x, a truncated form of 45w, was found to be directed against the n-terminal peptide sequence. sheep were immun ...199910195787
vaccination against taenia solium cysticercosis in pigs using native and recombinant oncosphere antigens.pigs were immunised with antigens derived from taenia solium oncospheres or with a pool of three recombinant antigens from taenia ovis, and subsequently challenged with t. solium eggs. the native oncosphere antigens induced 83% protection against viable, and 89% protection against the total number of cysticerci established following the challenge infection. immunisation with the recombinant t. ovis antigens induced 93% protection against the establishment of viable cysticerci, and 74% protection ...199910428641
duration of immunity, efficacy and safety in sheep of a recombinant taenia ovis vaccine formulated with saponin or selected adjuvants.the efficacy and safety of a recombinant taenia ovis protein was tested in sheep using 13 different adjuvant formulations, including oil adjuvants, aluminium salts, saponin, iscoms and deae-dextran. the oil adjuvants, saponin and deae-dextran gave the highest antibody responses and greatest degree of protection against challenge infection with t. ovis eggs. duration of immunity studies with a saponin based vaccine showed that highly significant protection (>90% reduction of cyst numbers) was ach ...199910507359
vaccination with plasmid dna expressing antigen from genomic or cdna gene forms induces equivalent humoral immune responses.the antibody response to dna vaccines containing either cdna or genomic gene forms of the host protective antigen, 45w from taenia ovis was compared in vaccinated balb/c mice and outbred sheep by enzyme linked immunosorbant assay (elisa). plasmid dna vaccines containing cdna or genomic forms of the taenia ovis host protective antigen 45w were constructed. in vitro transfection of cos7 cell monolayers with the dna vaccines revealed expression of full length, highly glycosylated 45w antigen of 40- ...199910547429
the use of recombinant ovine il-1beta and tnf-alpha as natural adjuvants and their physiological effects in vivo.in the present study we have investigated the use of recombinant ovine il-1beta and tnf-alpha both alone and in combination, as natural adjuvants in vaccination trials in sheep. initial experiments were conducted to investigate the physiological effects of the cytokines in vivo and determine what dose could be administered without adverse pyrogenic effects. even at the maximum dose tested (100 microg) the only significant physiological effect was a transient increase in body temperature of appro ...19989619487
a taenia solium oncosphere protein homologous to host-protective taenia ovis and taenia saginata 18 kda antigens.a taenia solium cdna (tsol-18) encoding a protein with close homology to host protective oncosphere antigens from taenia ovis (to18) and taenia saginata (tsa-18) is described here. tsol-18 was cloned from mrna obtained from hatched and activated oncospheres of t. solium. the high level of predicted amino acid sequence homology among tsol-18 and other host protective taeniid antigens suggests that the protein expressed by tsol-18 may be capable of being used as a vaccine against t. solium infecti ...19989650055
antibody and cytokine responses in efferent lymph following vaccination with different adjuvants.the cannulated efferent lymph node in sheep was used to examine the effect of different adjuvants on the antibody and cytokine responses following sub-cutaneous vaccination with a recombinant taenia ovis antigen (45 w). vaccination with quil a elicited relatively higher levels of igm than did ifa or al(oh)3. in general, 45 w specific igg1 and igg2 titres were higher and maintained for longer periods of time in lymph from sheep vaccinated with ifa and lower and shorter lived in animals which rece ...19989656452
modelling the prevalence of echinococcus and taenia species in small ruminants of different ages in northern jordan.a base-line survey of echinococcus granulosus, taenia hydatigena and t ovis were undertaken in order to investigate the transmission dynamics of these parasites in northern jordan. intensity of e. granulosus infection, in sheep, increased with age in a linear fashion whilst the asymptotic prevalence was one. this implied that e. granulosus is in an endemic steady state with no evidence of protective immunity in the intermediate host. the mean number of cysts increased by 1.66 per year with appro ...19989777724
nucleic acid vaccination of sheep: use in combination with a conventional adjuvanted vaccine against taenia ovis.this report describes the use of a nucleic acid vaccine in a large outbred animal species both alone and in combination with a conventionally adjuvanted vaccine. the gene encoding a host-protective antigen (45w) from the sheep parasite taenia ovis was cloned into the expression vector pcdna3 and the resultant plasmid termed pcdna3-45w. eleven of 15 sheep injected either intramuscularly or intradermally with pcdna3-45w mounted a serum antibody response to 45w which for both routes of injection wa ...19979046433
taenia ovis: copy number of genes encoding host-protective antigens determined by competitive pcr. 19979149244
urea/dtt solubilization of a recombinant taenia ovis antigen, 45w, expressed as a gst fusion protein results in enhanced protective immune response to the 45w moiety.vaccination and challenge infection experiments were conducted in sheep using different forms of a recombinant protein (45w) from the cestode parasite taenia ovis. 45w was expressed in escherichia coli as a fusion protein with glutathione-s-transferase (45w-gst) and was produced as both soluble protein and insoluble inclusion bodies. vaccination of animals with either the soluble or inclusion body derived protein resulted in the immune response being predominantly directed to the gst moiety of 4 ...19979160512
sequence analysis of a gene family encoding taenia ovis vaccine antigens expressed during embryogenesis of eggs.the 45w vaccine antigen of the cestode parasite taenia ovis is a member of a small gene family estimated to comprise six members. all six genes were cloned and characterised. nucleotide sequence analysis of the different family members identified a set of closely related genes exhibiting between 75.2 and 98.6% dna sequence homology. intron/exon structure for the various genes constituting the family was found to be conserved. open reading frame analysis and pairwise alignments of predicted polyp ...19979178269
sequential nucleic acid and recombinant adenovirus vaccination induces host-protective immune responses against taenia ovis infection in sheep.sheep were immunized with a protective recombinant antigen (45w) from the cestode parasite taenia ovis using three different vaccine delivery systems, either alone or in different combinations. the dna encoding 45w was cloned into the expression plasmid pcdna 3 and an ovine adenovirus to create nucleic acid and recombinant viral vector vaccines, respectively. sheep received two vaccinations with various combinations of these two delivery systems and/or purified recombinant 45w protein in a conve ...19979194099
rates of reinfection with echinococcus granulosus, taenia hydatigena, taenia ovis and other cestodes in a rural dog population in uruguay.a survey was undertaken to determine both the prevalence of, and reinfection rates with echinococcus granulosus and other cestodes in the department of florida, uruguay. baseline prevalence was determined in 303 rural dogs which then, in 4 groups, were re-examined 2, 4, 8 or 12 months later. baseline prevalences for e. granulosus, taenia hydatigena, taenia ovis and dipylidium caninum were 13.2, 13.9, 2.3 and 13.2%, respectively. the frequency distribution of e. granulosus was over-dispersed. dog ...19969198601
immune responses associated with protection in sheep vaccinated with a recombinant antigen from taenia ovis.this paper describes the evaluation of the protective antibody response of sheep to vaccination against taenia ovis infection with a defined recombinant antigen (45w). sera from 181 vaccinated sheep, collected prior to experimental challenge with t.ovis, were assessed for 45w specific iga, igg, igg1, igg2 and igm levels and these results correlated with protection data. there were significant relationships (p < 0.001) between igg, igg1 and igg2 titres and protection. serum iga levels did not cor ...19969223175
host-protective fragments and antibody binding epitopes of the taenia ovis 45w recombinant antigen.the protective efficacy of a recombinant taenia ovis vaccine antigen, 45w, was compared in sheep vaccine trials with antigen expressed by the full length 45w cdna and by incomplete copies of the cdna. vaccine, trials were also carried out using antigen expressed by a cdna (45s) having a sequence similar, but not identical, to 45w. stability of the 45w antigen expressed in escherichia coli was found to be increased after deletion of cdna sequence encoding 19 cooh-terminal amino acids. this trunca ...19969226688
gastrointestinal helminths of arctic foxes (alopex lagopus) from different bioclimatological regions in greenland.nine species of gastrointestinal helminths were recovered from 254 arctic foxes (alopex lagopus) from 8 different localities in greenland. prevalences of infection with the helminth species differed from area to area: toxascaris leonina (39-68%), strongyloides stercoralis (0-14%), mesocestoides lineatus (0-58%), diphyllobothrium dendriticum (0-15%), taenia ovis krabbei (0-70%), cryptocotyle sp. (0-3%), plagiorchis elegans (0-6%), and polymorphus sp. (0-3%). additionally, a taenia species, which ...19968627489
identification and cdna cloning of two novel low molecular weight host-protective antigens from taenia ovis oncospheres.oncosphere antigens of taenia ovis were solubilised in sodium dodecyl sulphate and separated by electrophoresis in polyacrylamide gels (sds-page). antigen-containing gel fractions cut from the region covering 18-12 kda were shown to be highly immunogenic in sheep challenge experiments. specific antisera against 2 candidate antigens at 18 and 16 kda were used to screen a cdna library prepared from t. ovis oncosphere mrna. recombinant proteins selected with antibody to the 16 and 18 kda native ant ...19968690544
parasite vaccine development: large-scale recovery of immunogenic taenia ovis fusion protein gst-45w(b/x) from escherichia coli inclusion bodies.genetically modified escherichia coli expressing the taenia ovis fusion protein gst-45w(b/x) as inclusion bodies were grown in volumes ranging up to 1000 l. bacteria were inactivated by heat or chemical treatment without affecting immunogenicity. the fusion protein was recovered in a highly immunogenic form from washed inclusion bodies and from urea-solubilised inclusion bodies. the fusion protein was found to be stable in solution after storage at 4 degrees c for up to 2 years. vaccines formula ...19968740543
antigen-specific iga-secreting cells induced by peripheral vaccination.antigen-specific iga-secreting cells were shown to be generated in peripheral lymph nodes following s.c. vaccination. the efferent duct of prefemoral lymph nodes of sheep were cannulated prior to vaccination at a site draining to the cannulated node. vaccines were contained a recombinant protein (taenia ovis 45w-gst) and either incomplete freund's, quil a or al(oh)3 as adjuvant. lymph fluid was examined for the presence of 45w-gst-specific antibody by elisa and antibody-secreting cells by enzyme ...19968799732
vaccination against worm parasites of animals.the 1990s have seen the culmination of decades of painstaking research with the registration and launch of tickgard (hoechst), a recombinant vaccine against boophilus microplus, and the provisional registration of a taenia ovis vaccine. research continues to hold promise for immunological control of echinococcus, fasciola, haemonchus, trichostrongylus and ostertagia. blood-sucking parasites (e.g. ticks and h. contortus) are susceptible to control by vaccines containing 'novel' or 'concealed' ant ...19968893462
[vaccines against parasitic diseases of domestic animals].this review presents short information on the present status and some future perspectives of vaccination against parasitoses of domestic animals. for the control of such parasitoses in some european countries only a few vaccines are registered: paracox and livacox (for coccidiosis in chickens), toxovax (for toxoplasmosis in sheep), pirodog (for babesiosis in dogs) and dictol (for dictyocaulosis in cattle). these are live vaccines containing attenuated parasites, except pirodog. as a world-wide i ...19969012013
pilot field trial of a recombinant taenia ovis vaccine in lambs exposed to natural infection.previous trials of an experimental taenia ovis vaccine using the recombinant antigen gst--45w(b/x) established that it was possible to achieve >90% protection against a single artificial challenge of t. ovis eggs. this trial was undertaken to assess vaccine efficacy against artificial challenge and natural infection acquired by lambs grazing contaminated pasture. two hundred romney lambs were vaccinated at 6 and 12 weeks of age. one hundred control lambs were not vaccinated but were allowed to r ...199616031921
the serological response of dogs to taenia ovis.the effect of 4-weekly anthelmintic dosing and other treatment regimes on the serological response of dogs to taenia ovis was examined. most dogs which were frequently fed infected meat and dosed with a cestocidal anthelmintic at 4-week intervals eventually showed a positive elisa absorbance. the absence of dosing, or intermittent dosing, of repeatedly infected dogs raised elisa absorbances to very high levels in most dogs and these absorbances took an increasingly longer time to fall after each ...199616031925
registration of generic alternatives to praziquantel for the control of taenia ovis. 199516031802
transmission dynamics of echinococcus granulosus, taenia hydatigena and taenia ovis in sheep in uruguay.a base-line survey was carried out on the transmission dynamics of echinococcus granulosus, taenia hydatigena and taenia ovis in sheep in the department of florida, uruguay. mean life expectancy at birth of the sheep population in this department was estimated at 3.5 and 4.8 years for male and female sheep, respectively. both intensity and prevalence of e. granulosus infection increased with age providing no evidence that immunity was acquired in the population. this revealed that e. granulosus ...19957558566
the influence of gamma inulin and algammulin on the immune response in sheep to a recombinant antigen of taenia ovis.gamma inulin and algammulin, two new adjuvants, were examined and compared with alum and freund's complete/incomplete adjuvant (fca/fia), for potentiation of cell-mediated immunity (cmi) and humoral immunity in sheep to a recombinant taenia ovis antigen. the ability to protect sheep when challenged with live t. ovis eggs was also assessed. the results showed that gamma inulin and algammulin induced a cmi response which was comparable to the fca/fia and alum groups and significantly higher than t ...19957639010
comparison of two enzyme immunoassays for the detection of haemonchus contortus infections in sheep.two enzyme-linked immunosorbent assays (elisa) using either excretory/secretory (es) products or crude somatic antigens (csa) of adult haemonchus contortus were compared for their ability to detect antibodies against h. contortus in sheep. serum samples obtained from a group of 32 h. contortus mono-infected sheep were tested in the two elisas and the obtained data were compared with the results of the faecal examinations of these sheep. the first sheep became patent 3 weeks post infection (p.i.) ...19957660570
a defined antigen for the serodiagnosis of taenia ovis infections in dogs.the evaginated scolex of taenia ovis secretes an antigen complex into defined culture medium that has been used to develop a cestode-specific enzyme-linked immunosorbent assay (elisa). we now describe an immunoblot test for antibodies to t. ovis based on the recognition of a 94-kda antigen band in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis profile of t. ovis scolex secretions. the test was specific for cestode infections in dogs and was 82% sensitive for the recognition of t. ...19957776128
taenia ovis recombinant vaccine--'quo vadit'.several years have elapsed since the publication by johnson et al. (1989) of the cloning of a recombinant antigen from the cestode parasite taenia ovis which stimulated high levels of protective immunity in sheep. a great deal of subsequent research and development was necessary to bring the fledgling vaccine to the point of being a registered commercial product. the results of these subsequent studies are dealt with briefly in this paper, including the results of field trials. the t. ovis vacci ...19957784129
characterization of the gene family encoding a host-protective antigen of the tapeworm taenia ovis.genomic structure has been determined for a gene encoding a host-protective antigen of the parasitic platyhelminth taenia ovis. an incomplete cdna, known as 45w, encodes the protective antigen. southern hybridisation experiments using 45w cdna as a probe, revealed that the 45w gene was a member of a multigene family. differential southern hybridisation and rapid amplification of cdna end (race) experiments were used to characterise the related genes, allowing the full-length coding region of the ...19958577320
developmental regulation of taenia ovis 45w gene expression. 19958577337
modelling of parasitic populations: cestodes.the philosophy of mathematical modelling as it applies to the epidemiology of cestode populations is reviewed. a model provides, via the "threshold theorem", a criterion for deciding in advance if a control programme can succeed in eradicating the parasite. in order to use this criterion it is necessary to have an estimate of the basic reproduction ratio, r0, which can only be obtained if reliable epidemiological data are available before the control programme is started. a model has been used t ...19947846848
metacestodes of sheep with special reference to their epidemiological status, pathogenesis and economic implications in fars province, iran.this study was undertaken over a period of 2 years. of 7992 sheep examined, 2088 (26.12%), 2266 (28.36%), 15 (0.19%) and 738 (9.8%) were infected with echinococcus granulosus, taenia hydatigena, taenia ovis and taenia multiceps metacestodes, respectively. the prevalence was higher in animals belonging to migratory tribal people than in those owned by the permanent residents of fars province. dogs in the former group also showed significantly higher levels of infection with e. granulosus (33.3%) ...19948171825
vaccination against cestode parasites.cestodes are tapeworm parasites. infection in the intermediate host with larval (metacestode) parasites causes medically and economically important diseases known as hydatidosis and cysticercosis. immunization against experimental infection with metacestode parasites has been highly successful, in marked contrast with the relative ineffectiveness of vaccines against infection with most parasitic organisms. high levels of immunity against a challenge infection with taeniid cestode eggs can be sti ...19938270273
gnffrfamide: a novel fmrfamide-immunoreactive peptide isolated from the sheep tapeworm, moniezia expansa.the widespread distribution of fmrfamide-immunoreactivity in platyhelminth nervous systems has been demonstrated immunocytochemically. here we report the isolation and primary structure of the first platyhelminth fmrfamide-related peptide (farp) from the tapeworm, moniezia expansa. the peptide was found to have a molecular mass of 785 da and a primary structure of gly-asn-phe-phe-arg- phe-nh2 (gnffrfamide). acid alcohol extracts of this platyhelminth contained only this single farp which had a p ...19938323531
identification of host-protective antigens of taenia ovis oncospheres.sheep were fully protected against challenge infection following immunization with a homogenate of t. ovis oncospheres. ultracentrifugation of sonicated oncospheres either alone or in the presence of a range of detergents did not reduce the immunogenicity of the extracts. solubilization of oncosphere extracts in non-ionic detergents or sodium dodecyl sulphate (sds) enabled analysis of host-protective antigens by isoelectric focusing (ief) and electrophoresis in polyacrylamide gels (sds-page), re ...19938468135
the primary structure of neuropeptide f (npf) from the garden snail, helix aspersa.neuropeptide f (npf), originally isolated from the sheep tapeworm, moniezia expansa, consists of 39 amino acid residues terminating in a phenylalaninamide. an analogous neuropeptide has been isolated and sequenced from extracts of circumoesophageal ganglia of the garden snail, helix aspersa. this neuropeptide exhibits partial primary structural similarity to members of the vertebrate neuropeptide y (npy)/pancreatic polypeptide (pp) superfamily. npf is thus of widespread occurrence in the nervous ...19921472263
comparison of an indirect haemagglutination assay and an elisa for diagnosing fasciola hepatica in experimentally and naturally infected sheep.an enzyme-linked immunosorbent assay (elisa) with somatic (s) or excretory-secretory antigens (es) was compared with an indirect haemagglutination assay (iha) for ability to detect antibodies against fasciola hepatica in sheep. the specificity of both assays was determined by testing sera collected from sheep experimentally or naturally mono-infected with fasciola hepatica, haemonchus contortus, ostertagia circumcincta, cooperia curticei, taenia ovis, eimeria spp., trichostrongylus vitrinus, tri ...19921485406
echinococcus granulosus: use of an intermediate host mouse model to evaluate sources of protective antigens and a role for antibody in the immune response.a balb/cj mouse model was used to determine which stage of the e. granulosus life cycle possessed the most potent protective antigens. mice were immunized with crude extracts of protoscoleces, brood capsules, cyst fluid, adult worm tissue, eggs or oncospheres and then challenged intraperitoneally with 600 activated oncospheres. sonically disrupted oncospheres induced the highest levels of protection (greater than 90%) at doses greater than or equal to 10(3) oncosphere equivalents per mouse. high ...19921644518
cestode vaccines.studies over the past 20 years have clearly shown the potential for developing vaccines against larval cestode infections of man and animals. the important larval cestode infections of man (echinococcus granulosus--hydatidosis: taenia solium--cysticercosis) involve domesticated animals as intermediate hosts in their natural life-cycles. these animals develop strong immunity against reinfection, and immunity can be artificially induced by vaccination with oncosphere antigens. a major stumbling bl ...19911822908
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