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Trichuris suis is a common parasitic helminth of pigs. As with many other parasites, T. suis ensures its own survival by evading host immune responses, but little is known about how this is achieved. MicroRNAs (miRNA) have been shown to be involved in various immunological processes by post-transcriptional regulation of specific genes, and the potential of using these molecules as biomarkers of disease is currently being examined. It has recently been shown that parasites may secrete extracellular structures such as exosomes and microvesicles, containing proteins and miRNA. The fusion of these structures with host cells has been demonstrated, and a role of exosome-derived miRNA in host gene regulation has been suggested. In the present study, we show that exosome- and microvesicular-like structures are secreted by T. suis L1 larvae and also demonstrate the presence of miRNA-sized RNA inside these structures. A potential role of these molecules in host-parasite interactions is suggested. In addition, an electron-dense layer covering the surface of the larvae was observed, which may play a function in host immune evasion.

Cross-species infection among humans, chimpanzees (Pan troglodytes) and baboons (Papio spp.) is potentially a significant public health issue in Africa, and of concern in the conservation of P. troglodytes. However, to date, no statistical comparisons have been made between the prevalence, richness and composition of parasite communities in sympatric populations of baboons and P. troglodytes. We compared parasite communities in sympatric P. troglodytes and Papio papio living in a wilderness site, in the Republic of Senegal, West Africa. We asked whether, in the absence of humans, there are significant differences between these hosts in their interactions with gastrointestinal parasites. We tested whether host, location, or time of collection accounted for variation in prevalence, richness and community composition, and compared prevalence across six studies. We concluded that, despite being closely related, there are significant differences between these two hosts with respect to their parasite communities. At our study site, prevalence of Balantidium, Trichuris and Watsonius was higher in P. papio. Papio papio harboured more parasites per host, and we found evidence of a positive association between Trichuris and Balantidium in P. troglodytes but not P. papio.

Captive primates are susceptible to gastrointestinal (GIT) parasitic infections, which are often zoonotic and can contribute to morbidity and mortality. Fecal samples were examined by the means of direct smear, fecal flotation, fecal sedimentation, and fecal cultures. Of 26.51% (317/1196) of the captive primates were diagnosed gastrointestinal parasitic infections. Trichuris spp. were the most predominant in the primates, while Entamoeba spp. were the most prevalent in Old World monkeys (P < 0.05). These preliminary data will improve the management of captive primates and the safety of animal keepers and visitors., (© 2015 The Authors. Journal of Medical Primatology Published by John Wiley & Sons Ltd.)

Trichuris serrata, a whipworm of cats, can cause inflammation in the cecum and upper portion of the large intestine. It is unknown if the virulence and pathology of T. serrata differ from Trichuris campanula, the other species in cats. Distinguishing the species based on egg size is challenging. In addition, Trichuris eggs can be difficult to distinguish from Capillaria spp. This paper presents the first molecular description of T. serrata. The 18S ribosomal RNA (rRNA) gene was sequenced from male adult worms sourced from two unrelated cats on St. Kitts. Based on the analysis of 651 base pairs, T. serrata was found to be different than any other Trichuris species for which published sequencing of the 18S rRNA gene is available. A dendrogram was developed using Molecular Evolutionary Genetics Analysis version 6.0, and evolutionary history was inferred using the minimum evolution method. T. serrata was found to be most closely related to Trichuris vulpis, the Trichuris of dogs. Further development of the methodology could enable distinguishing T. serrata, T. campanula, and Capillaria spp. infections in cats and aid in diagnosis.

Background: Since the nematodes Trichuris trichiura and T. suis are morphologically indistinguishable, genetic analysis is required to assess epidemiological cross-over between people and pigs. This study aimed to clarify the transmission biology of trichuriasis in Ecuador., Findings: Adult Trichuris worms were collected during a parasitological survey of 132 people and 46 pigs in Esmeraldas Province, Ecuador. Morphometric analysis of 49 pig worms and 64 human worms revealed significant variation. In discriminant analysis morphometric characteristics correctly classified male worms according to host species. In PCR-RFLP analysis of the ribosomal Internal Transcribed Spacer (ITS-2) and 18S DNA (59 pig worms and 82 human worms), nearly all Trichuris exhibited expected restriction patterns. However, two pig-derived worms showed a "heterozygous-type" ITS-2 pattern, with one also having a "heterozygous-type" 18S pattern. Phylogenetic analysis of the mitochondrial large ribosomal subunit partitioned worms by host species. Notably, some Ecuadorian T. suis clustered with porcine Trichuris from USA and Denmark and some with Chinese T. suis., Conclusion: This is the first study in Latin America to genetically analyse Trichuris parasites. Although T. trichiura does not appear to be zoonotic in Ecuador, there is evidence of genetic exchange between T. trichiura and T. suis warranting more detailed genetic sampling.

Embryonated eggs of the pig whipworm Trichuris suis (TSOee) constitute the active pharmaceutical ingredient (API) in a medicinal product explored in human clinical trials against several immune-mediated diseases. The measurement of TSO biological potency (hatchability and infectivity) is a requirement for the assessment of TSO's pharmacological potency in human clinical trials. The present study aims to validate the dose-dependent establishment of T. suis larvae in Göttingen minipigs and eventual clinical implication of a dose range (1000-10,000 TSO). Four groups of 5 minipigs were inoculated with doses of 1000, 2500, 7500, and 10,000 TSOee, respectively, to evaluate a range of concentrations of TSOee in a minipig infectivity model. Unembryonated eggs (TSOue) were added to keep the total egg number in the inoculum constant at 10,000 eggs. Two groups received 2500 and 7500 TSOee per pig without the addition of TSOue as controls. The intestinal larval establishment at 21 days post inoculation (dpi) demonstrated a clear positive linear dose-response relationship between numbers of inoculated TSOee and recovered larvae. There was a low level of variation in larval counts in all study groups. Thus, the infectivity model in minipigs within the tested dose range offers a reliable, sensitive and accurate assay for testing biological potency of TSO., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Background: Whipworms (Trichuris sp.) are a globally distributed genus of parasitic helminths that infect a diversity of mammalian hosts. Molecular methods have successfully resolved porcine whipworm, Trichuris suis, from primate whipworm, T. trichiura. However, it remains unclear whether T. trichiura is a multi-host parasite capable of infecting a wide taxonomic breadth of primate hosts or a complex of host specific parasites that infect one or two closely related hosts., Methods and Findings: We examined the phylogenetic structure of whipworms in a multi-species community of non-human primates and humans in Western Uganda, using both traditional microscopy and molecular methods. A newly developed nested polymerase chain reaction (PCR) method applied to non-invasively collected fecal samples detected Trichuris with 100% sensitivity and 97% specificity relative to microscopy. Infection rates varied significantly among host species, from 13.3% in chimpanzees (Pan troglodytes) to 88.9% in olive baboons (Papio anubis). Phylogenetic analyses based on nucleotide sequences of the Trichuris internal transcribed spacer regions 1 and 2 of ribosomal DNA revealed three co-circulating Trichuris groups. Notably, one group was detected only in humans, while another infected all screened host species, indicating that whipworms from this group are transmitted among wild primates and humans., Conclusions and Significance: Our results suggest that the host range of Trichuris varies by taxonomic group, with some groups showing host specificity, and others showing host generality. In particular, one Trichuris taxon should be considered a multi-host pathogen that is capable of infecting wild primates and humans. This challenges past assumptions about the host specificity of this and similar helminth parasites and raises concerns about animal and human health.

Research in mouse and human clearly identified subsets of T helper (Th) cells based on nuclear expression of specific lineage transcription factors. In swine, however, transcription factor based detection of functional subpopulations of porcine Th cells by flow cytometry is so far limited to regulatory T cells via Foxp3. T-bet and GATA-3 are the transcription factors that regulate commitment to Th1 or Th2 cells, respectively. In this study we prove GATA-3 and T-bet expression in porcine CD4(+) cells polarized in vitro. Importantly, GATA-3 and T-bet expressing cells were detectable in pigs infected with pathogens associated with Th2 and Th1 immune responses. Increased frequencies of GATA-3 positive CD4(+) cells are found in vivo in pigs experimentally infected with the nematode Trichuris suis, whereas porcine reproductive and respiratory syndrome virus (PRRSV) infection elicited T-bet positive CD4(+) T cells. Analysing the immune status of pre-weaning piglets with intrauterine growth restriction (IUGR) we found an increased expression of Foxp3, T-bet and GATA-3 in CD4(+) and CD4(+)CD8(+) double-positive T cells in systemic and intestinal compartments of IUGR piglets. Hence, we established the detection of porcine Th1 and Th2 cells via T-bet and GATA-3 and show that the porcine lineage transcription factors are differentially regulated very early in life depending on the developmental status., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

The apparent monthly prevalence of endoparasite infections was measured from 20,991 dogs that had fecal examinations performed upon presentation to the Veterinary Hospital of the University of Pennsylvania between 1984 and 2007. In the period from 1984 to 1991, the mean monthly prevalence of endoparasites was 5.32% for ascarids, 9.80% for hookworms, 9.64% for whipworms, 1.84% for tapeworms (Dipylidium caninum), 4.59% for Giardia species, and 3.04% for coccidia. Based on Student's t tests, the prevalence of ascarids (1.99%), hookworms (1.48%), whipworms (2.33%), and tapeworms (0.29%) were found to be significantly lower in the period from 2000 to 2007. Plots of the smoothed monthly averages revealed that the declines in prevalence occurred shortly after the introduction of modern heartworm and flea preventatives to the commercial market. In the latter study period, 79.8% of dogs were on monthly heartworm prevention and 74.0% were on monthly flea prevention. There were no significant differences in the prevalence of either Giardia species or coccidia species between study time periods. Overall, the findings suggest that heartworm and flea preventatives have had cascade effects on endoparasite prevalence in the population of well-cared-for dogs., (Copyright © 2014 Elsevier B.V. All rights reserved.)

In the present work, a morphological and biometrical study of whipworms Trichuris Roederer, 1761 (Nematoda: Trichuridae) parasitizing Colobus guereza kikuyensis has been carried out. Biometrical and statistical data showed that the mean values of individual variables between Trichuris suis and Trichuris sp. from C. g. kikuyensis differed significantly (P < 0.001) when Student's t test was performed: seven male variables (width of esophageal region of body, maximum width of posterior region of body, width in the place of junction of esophagus and the intestine, length of bacillary stripes, length of spicule, length of ejaculatory duct, and distance between posterior part of testis and tail end of body) and three female variables (width of posterior region of body, length of bacillary stripes, and distance of tail end of body and posterior fold of seminal receptacle). The combination of these characters permitted the discrimination of T. suis with respect to Trichuris sp. from C. g. kikuyensis, suggesting a new species of Trichuris. Furthermore, males of Trichuris sp. from C. g. kikuyensis showed a typical subterminal pericloacal papillae associated to a cluster of small papillae that were absent in males of T. suis, while females of Trichuris from Colobus appeared with a vulval region elevated/over-mounted showing a crater-like appearance. The everted vagina showed typical triangular sharp spines by optical microscopy and SEM. Thus, the existence of a new species of Trichuris parasitizing C. g. kikuyensis has been proposed.

Background: Cysteine proteinases (CPs) from papaya (Carica papaya) possess anthelmintic properties against human soil-transmitted helminths (STH, Ascaris lumbricoides, Trichuris trichiura and hookworm), but there is a lack of supportive and up-to-date efficacy data. We therefore conducted two randomized controlled trials in pigs to assess the efficacy of papaya CPs against experimental infections with T. suis., Methods: First, we assessed efficacy by means of egg (ERR) and adult worm reduction rate (WRR) of a single-oral dose of 450 μmol active CPs (CP450) against low (inoculum of 300 eggs) and high (inoculum of 3,000 eggs) intensity T. suis infections and compared the efficacy with those obtained after a single-oral dose of 400 mg albendazole (ALB). In the second trial, we determined and compared the efficacy of a series of CP doses (45 [CP45], 115 [CP115], 225 [CP225], and 450 [CP450] μmol) against high intensity infections., Results: CP450 was highly efficacious against both levels of infection intensity, resulting in ERR and WRR of more than 97%. For both levels of infection intensity, CP450 was significantly more efficacious compared to ALB by means of WRR (low infection intensity: 99.0% vs. 39.0%; high infection intensity; 97.4% vs. 23.2%). When the efficacy was assessed by ERR, a significant difference was only observed for high intensity infections, CP450 being more efficacious than ALB (98.9% vs. 59.0%). For low infection intensities, there was no significant difference in ERR between CP450 (98.3%) and ALB (64.4%). The efficacy of CPs increased as a function of increasing dose. When determined by ERR, the efficacy ranged from 2.1% for CP45 to 99.2% for CP450. For WRR the results varied from -14.0% to 99.0%, respectively. Pairwise comparison revealed a significant difference in ERR and WRR only between CP45 and CP450, the latter being more efficacious., Conclusions: A single dose of 450 μmol CPs provided greater efficacy against T. suis infections in pigs than a single-oral dose of 400 mg ALB. Although these results highlight the possibility of papaya CPs for controlling human STH, further development is needed in order to obtain and validate an oral formulation for human application.

One adult (13-yr-old) and two young (3-4-yr-old) male dromedary camels (Camelus dromedarius) from the Seoul Zoo displayed anorexia and chronic diarrhea for 2 wk. Direct fecal smear examination revealed Trichuris spp. infection. After confirmation of the infection, fenbendazole was orally administered as a suspension; this was repeated two times at 3-wk intervals. A high initial dose (20 mg/kg) was followed by administration at the recommended dose (10 mg/kg). Starting on the day following the first treatment, a large number of adult whipworms were discharged with the feces over a 3-day period. Two young male dromedary camels gradually recovered. However, the adult male dromedary camel developed continuous bloody mucoid diarrhea and died 2 days after treatment. Postmortem examination revealed that numerous whipworms were attached to the mucosa throughout the large intestine.

Trichuris trichiura and Trichuris suis parasitize (at the adult stage) the caeca of humans and pigs, respectively, causing trichuriasis. Despite these parasites being of human and animal health significance, causing considerable socio-economic losses globally, little is known of the molecular characteristics of T. trichiura and T. suis from China. In the present study, the entire first and second internal transcribed spacer (ITS-1 and ITS-2) regions of nuclear ribosomal DNA (rDNA) of T. trichiura and T. suis from China were amplified by polymerase chain reaction (PCR), the representative amplicons were cloned and sequenced, and sequence variation in the ITS rDNA was examined. The ITS rDNA sequences for the T. trichiura and T. suis samples were 1222-1267 bp and 1339-1353 bp in length, respectively. Sequence analysis revealed that the ITS-1, 5.8S and ITS-2 rDNAs of both whipworms were 600-627 bp and 655-661 bp, 154 bp, and 468-486 bp and 530-538 bp in size, respectively. Sequence variation in ITS rDNA within and among T. trichiura and T. suis was examined. Excluding nucleotide variations in the simple sequence repeats, the intra-species sequence variation in the ITS-1 was 0.2-1.7% within T. trichiura, and 0-1.5% within T. suis. For ITS-2 rDNA, the intra-species sequence variation was 0-1.3% within T. trichiura and 0.2-1.7% within T. suis. The inter-species sequence differences between the two whipworms were 60.7-65.3% for ITS-1 and 59.3-61.5% for ITS-2. These results demonstrated that the ITS rDNA sequences provide additional genetic markers for the characterization and differentiation of the two whipworms. These data should be useful for studying the epidemiology and population genetics of T. trichiura and T. suis, as well as for the diagnosis of trichuriasis in humans and pigs.

The aim of the present study was to investigate the population dynamics and potential interactions between Trichuris suis and Oesophagostomum dentatum in experimentally co-infected pigs, by quantification of parasite parameters such as egg excretion, worm recovery and worm location. Forty-eight helminth naïve pigs were allocated into four groups. Group O was inoculated with 20 O. dentatum L3/kg/day and Group T with 10 T. suis eggs/kg/day. Group OT was inoculated with both 20 O. dentatum L3/kg/day and 10 T. suis eggs/kg/day, while Group C was kept as an uninfected control group. All inoculations were trickle infections administered twice weekly and were continued until slaughter. Faecal samples were collected from the rectum of all pigs at day 0, and twice weekly from 2 to 9 weeks post first infection (wpi). Six pigs from each group were necropsied 5 wpi and the remaining 6 pigs from each group were necropsied 10 wpi. The faecal egg counts (FEC) and total worm burdens of O. dentatum were dramatically influenced by the presence of T. suis, with significantly lower mean FECs and worm burdens at 5 and 10 wpi compared to single infected pigs. Furthermore, in the presence of T. suis we found that O. dentatum was located more posteriorly in the gut. The changes in the Trichuris population were less prominent, but faecal egg counts, worm counts 5 wpi (57% recovered vs. 39%) and the proportion of infected animals at 10 wpi were higher in Group OT compared to Group T. The location of T. suis was unaffected by the presence of O. dentatum. These results indicate an antagonistic interaction between T. suis and O. dentatum which is dominated by T. suis., (Copyright © 2013 Elsevier B.V. All rights reserved.)

During a survey of the helminth community of several rodent species in the Morogoro region (Tanzania), Trichuris whipworms (Nematoda: Trichuridae) were found in the ceca of the Natal multimammate mouse, Mastomys natalensis and a gerbil, Gerbilliscus vicinus (both Rodentia: Muridae). The taxonomic literature regarding Trichuris from African native rodents describes 10 species, but includes few metric and morphologic characters that discriminate between some of the pairs. The whipworms we sampled in Tanzanian Natal multimammate mice and gerbils were morphologically identified, respectively, as Trichuris mastomysi Verster, 1960 and Trichuris carlieri Gedoelst, 1916 sensu lato, but with characters that overlap or partially overlap with the cosmopolitan Murinae whipworm, Trichuris muris , already reported from several rodents in Africa. To clarify our identification, we sequenced the ITS-1, 5.8S, and ITS-2 ribosomal DNA region of the worms' nuclear genome. The genetic analyses clearly distinguish the whipworms we found in M. natalensis from those found in the gerbil, and both of these from T. muris whipworm reference sequences. The overlap of morphological characters between rodent whipworms suggests that reports of T. muris from rodent species not closely related to Murinae in other parts of Africa should be treated with caution.

The efficacy of emodepside plus toltrazuril oral suspension for dogs (Procox®, Bayer) against Trichuris vulpis was evaluated in a controlled, blinded and randomised laboratory study. Twenty naturally infected dogs were included. Dogs in the treatment group received the minimum therapeutic dose of 0.45 mg emodepside and 9 mg toltrazuril per kg body weight, while dogs in the control group were left untreated. Efficacy was calculated based on worm counts after necropsy on Day 7 post treatment. Additionally, all faeces were collected and examined for expelled worms. The treatment was 100 % effective. A total of 233 adult worms (geometric mean 17.0) and 3 immature adult worms were found in the control group at necropsy. Adequacy of infection was demonstrated. The treated group excreted a total of 186 adult worms within 2 days after treatment. Additionally, all dogs were co-infected with Uncinaria stenocephala. Efficacy against this parasite was 99.8 %. No side effects of the treatment were observed. This study demonstrates that in addition to the formerly proven efficacy against Toxocara canis, Ancylostoma caninum and Uncinaria stenocephala, emodepside plus toltrazuril suspension is also effective against T. vulpis and thus represents a convenient treatment option for dogs co-infected with whipworms and coccidia.

The whipworm of humans, Trichuris trichiura, is responsible for a neglected tropical disease (NTD) of major importance in tropical and subtropical countries of the world. Whipworms also infect animal hosts, including pigs, dogs and non-human primates, cause clinical disease (trichuriasis) similar to that of humans. Although Trichuris species are usually considered to be host specific, it is not clear whether non-human primates are infected with T. trichiura or other species. In the present study, we sequenced the complete mitochondrial (mt) genome as well as the first and second internal transcribed spacers (ITS-1 and ITS-2) of Trichuris from the François' leaf-monkey (langur), and compared them with homologous sequences from human- and pig-derived Trichuris. In addition, sequence comparison of a conserved mt ribosomal gene among multiple individual whipworms revealed substantial nucleotide differences among these three host species but limited sequence variation within each of them. The molecular data indicate that the monkey-derived whipworm is a separate species from that of humans. Future work should focus on detailed population genetic and morphological studies (by electron microscopy) of whipworms from various non-humans primates and humans.

The mara (Dolichotis patagonum) is a species classified as "Near Threatened" by the International Union for Conservation of Nature. In the wild, it inhabits only Argentina, but it is also kept in zoos around the world. In order to investigate the endoparasites of the maras kept in the Attica Zoological Park, Greece, four fecal examinations were performed in a period of 4 yr (2008-2011) by standard parasitologic methods. Cysts of the protozoan parasite Giardia spp. and eggs of the nematode Trichuris spp. were found in all four examinations. The possible routes of infection of the maras and the importance of these parasites to other animals and to humans are discussed.

A recurrent problem in the control of whipworm (Trichuris spp.) infections in many animal species and man is the relatively low efficacy of treatment with a single application of benzimidazoles (BZs). The presence of single nucleotide polymorphisms (SNPs) in codons 167, 198 and 200 in the beta-tubulin gene has been associated with BZ anthelmintic resistance in intestinal nematodes of veterinary importance. We hypothesized that the low susceptibility to BZ could be related to a natural tolerance or induced resistance caused by BZ-resistant associated SNPs. The aim of the present study was therefore to investigate the presence of these SNPs in the beta-tubulin gene of Trichuris spp. obtained from a range of animals. DNA was extracted from a total of 121 Trichuris spp. adult whipworm specimens obtained from 6 different host species. The number of worms from each host was pig: 31, deer: 21, sheep: 18, mouse: 17, dog: 19 and Arabian camels: 14. A pooled sample of Trichuris eggs from 3 moose was also used. In order to amplify the beta-tubulin fragments which covered codons 167, 198 and 200 of the gene, degenerate primers were designed. The sequences obtained were used to design species specific primers and used to amplify a ~476 bp fragment of the beta-tubulin gene. The PCR products were sequenced, analysed and evaluated. We did not identify SNPs in codons 167, 198 or 200 that led to amino acid substitutions in any of the studied Trichuris spp., but genetic variation expected to be related to species differences was observed. The cluster analysis showed close evolutionary relationship between Trichuris spp. from ruminants and between mouse and dog whereas the pig-derived worms, T. suis, clustered with T. trichiura obtained from Genbank., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Trichuris nematodes were isolated from roe deer (Capreolus capreolus). At first, nematodes were determined using morphological and biometrical methods. Subsequently genomic DNA was isolated and the ITS1-5.8S-ITS2 segment from ribosomal DNA (RNA) was amplified and sequenced using PCR techniques. With u sing morphological and biometrical methods, female nematodes were identified as Trichuris globulosa, and the only male was identified as Trichuris ovis. The females were classified into four morphotypes. However, analysis of the internal transcribed spacers (ITS1-5.8S-ITS2) of specimens did not confirm this classification. Moreover, the female individuals morphologically determined as T. globulosa were molecularly identified as Trichuris discolor. In the case of the only male molecular analysis match the result of the molecular identification. Furthermore, a comparative phylogenetic study was carried out with the ITS1 and ITS2 sequences of the Trichuris species from various hosts. A comparison of biometric information from T. discolor individuals from this study was also conducted.

Objective: To study nematode parasites morphology of Hystrix javanica (H. javanica), both through the feces and internal organs., Methods: Feces were observed by direct smear method, internal organs were observed after dissecting the host. Specimens for light microscopy examination were fixed with 70% warm alcohol, cleared and mounted in lactophenol for wet mounting. Specimens for SEM examination were postfixed in cacodylate buffer and glutaraldehyde, dehydrated through a graded series of alcohol and freeze dried. The specimens were attached to stubs with double cello-tape, coated with gold and observed with a JSM5310 LV electron microscope. Figures were made with the aid of a drawing tube attached to Olympus compound microscope, other figures were photographs of scanning electron microscope images. Measurements were given in micrometers as the mean followed by the range in parentheses, unless otherwise stated., Results: The nematode species found in the intestine of H. javanica are Gireterakis girardi and a new species, Trihuris landak. The new species differs with previously reported species from Hystrix because of having stylet and short cervical alae. The pattern of bacillary band is closed to Trichuris trichiurus, the species that infect human, but differs because the surface of its vulva is not covered with densely spine., Conclusions: The species of nematodes found on H. javanica were Gireterakis girardi and a new species Trichuris landak n.sp. Those two species are newly recorded in Indonesia.

This study examined sequence variation in three mitochondrial DNA (mtDNA) regions, namely cytochrome c oxidase subunit 1 (cox1), NADH dehydrogenase subunit 5 (nad5) and cytochrome b (cytb), among Trichuris ovis isolates from different hosts in Guangdong Province, China. A portion of the cox1 (pcox1), nad5 (pnad5) and cytb (pcytb) genes was amplified separately from individual whipworms by PCR, and was subjected to sequencing from both directions. The size of the sequences of pcox1, pnad5 and pcytb was 618, 240 and 464 bp, respectively. Although the intra-specific sequence variations within T. ovis were 0-0.8% for pcox1, 0-0.8% for pnad5 and 0-1.9% for pcytb, the inter-specific sequence differences among members of the genus Trichuris were significantly higher, being 24.3-26.5% for pcox1, 33.7-56.4% for pnad5 and 24.8-26.1% for pcytb, respectively. Phylogenetic analyses using combined sequences of pcox1, pnad5 and pcytb, with three different computational algorithms (maximum likelihood, maximum parsimony and Bayesian inference), indicated that all of the T. ovis isolates grouped together with high statistical support. These findings demonstrated the existence of intra-specific variation in mtDNA sequences among T. ovis isolates from different hosts, and have implications for studying molecular epidemiology and population genetics of T. ovis.

For many years, whipworms (Trichuris spp.) have been described with a relatively narrow range of both morphological and biometrical features. Moreover, there has been insufficient discrimination between congeners (or closely related species). In the present study, we determined the complete mitochondrial (mt) genomes of two whipworms Trichuris ovis and Trichuris discolor, compared them and then tested the hypothesis that T. ovis and T. discolor are distinct species by phylogenetic analyses using Bayesian inference, maximum likelihood and maximum parsimony) based on the deduced amino acid sequences of the mt protein-coding genes. The complete mt genomes of T. ovis and T. discolor were 13,946 bp and 13,904 bp in size, respectively. Both mt genomes are circular, and consist of 37 genes, including 13 genes coding for proteins, 2 genes for rRNA, and 22 genes for tRNA. The gene content and arrangement are identical to that of human and pig whipworms Trichuris trichiura and Trichuris suis. Taken together, these analyses showed genetic distinctiveness and strongly supported the recent proposal that T. ovis and T. discolor are distinct species using nuclear ribosomal DNA and a portion of the mtDNA sequence dataset. The availability of the complete mtDNA sequences of T. ovis and T. discolor provides novel genetic markers for studying the population genetics, diagnostics and molecular epidemiology of T. ovis and T. discolor., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Natural habitat fragmentation and reducing habitat quality have resulted in an increased appearance of Japanese macaques, Macaca fuscata (Gray, 1870), in suburban areas in Japan. To investigate the risk of zoonotic infections, a coprological survey of helminth eggs passed by wild Japanese macaques was carried out in 2009 and 2010 in Shiga Prefecture, Japan. Microscopic examination found helminth eggs in high prevalence, and nucleotide sequencing of DNA extracted from the eggs identified Oesophagostomum cf. aculeatum and Trichuris trichiura. A fecal culture also detected infective larvae of Strongyloides fuelleborni. These zoonotic nematodes pose a potential health issue to local people in areas frequented by Japanese macaques.

The whipworms Trichuris trichiura and Trichuris suis in humans and pigs, respectively, are believed to be two different species yet closely related. Morphologically, adult worms, eggs and larvae of the two species are indistinguishable. The aim of this study was to examine the genetic variation of Trichuris sp. mainly recovered from natural infected pigs and humans. Worm material isolated from humans and pigs living in the same geographical region in Uganda were analyzed by PCR, cloning and sequencing. Measurements of morphometric characters were also performed. The analysis of the ITS-2 (internal transcribed spacer) region showed a high genetic variation in the human-derived worms with two sequence types, designated type 1 and type 2, differing with up to 45%, the type 2 being identical to the sequence found in pig-derived worms. A single human-derived worm showed exclusively the type 2-genotype (T. suis-type) and three cases of 'heterozygote' worms in humans were identified. However, the analysis showed that sympatric Trichuris primarily assorted with host origin. Sequence analysis of a part of the genetically conserved β-tubulin gene confirmed two separate populations/species but also showed that the 'heterozygote' worms had a T. suis-like β-tubulin gene. A PCR-RFLP on the ITS-2 region was developed, that could distinguish between worms of the pig, human and 'heterozygote' type. The data suggest that Trichuris in pigs and humans belong to two different populations (i.e. are two different species). However, the data presented also suggest that cross-infections of humans with T. suis takes place. Further studies on sympatric Trichuris populations are highly warranted in order to explore transmission dynamics and unravel the zoonotic potential of T. suis., (Copyright © 2012 Elsevier B.V. All rights reserved.)

The whipworm Trichuris muris was recovered from the caecum of the wild rodent Psammomys obessus trapped from Sinai Peninsula, Egypt. The cuticular surface ultrastructure is described using SEM. T. muris is closely related to other Trichuris species but can be distinguished from them mainly by differences in the posterior end of males. Details of the surface such as the bacillary gland, cuticular inflations and several morphological details obtained by scanning electron microscopy confirmed the characteristics that differentiate the species. P. obessus (Cretzschmar, 1828) is considered a new host record and Sinai is considered a new locality for the genus. This may through light on the spread of T. muris between Asia and Africa.

Background: Capillaria aerophila, Capillaria boehmi and Trichuris vulpis are trichuroid nematodes affecting wild and companion animals all over the World. The canine intestinal whipworm, T. vulpis, is the most common and well- known in veterinary practice, whereas the respiratory C. aerophila and C. boehmi have been rarely reported in pets as a likely consequence of overlapping morphometric and morphological features of the eggs, which impair a correct etiological diagnosis., Findings: In December 2011, a mixed infestation by T. vulpis, C. aerophila and C. boehmi was diagnosed in an asymptomatic dog living in central Italy. Morphometric and morphological findings and pictures of the eggs found at the copromicroscopic analysis are herein reported., Conclusions: The present work demonstrates that when trichuroid eggs are found in a faecal sample from a dog, a careful morphological and morphometric analysis of individual parasite elements is mandatory. Key diagnostic features (i.e., size, wall surface pattern and aspects of plugs) should be carefully examined when eggs with overlapping shape and appearance are detected. In conclusion, given the importance in clinical practice of canine trichuroids and the zoonotic potential of C. aerophila, these nematodes should be included into the differential diagnosis of intestinal and respiratory parasitoses of dogs by a thorough microscopic analysis of all trichuroid ova present in microscopic fields.

The two geohelminths, Ascaris lumbricoides and Trichuris trichiura, infect more than a billion people worldwide but are only reported sporadically in the developed part of the world. In contrast, the closely related species A. suum and T. suis in pigs have a truly global distribution, with infected pigs found in most production systems. In areas where pigs and humans live in close proximity or where pig manure is used as fertilizer on vegetables for human consumption, there is a potential risk of cross-infections. We therefore review this relationship between Ascaris and Trichuris in the human and pig host, with special focus on recent evidence concerning the zoonotic potential of these parasites, and identify some open questions for future research.

Helminth parasites ensure their survival by regulating host immunity through mechanisms that dampen inflammation. These properties have recently been exploited therapeutically to treat human diseases. The biocomplexity of the intestinal lumen suggests that interactions between the parasite and the intestinal microbiota would also influence inflammation. In this study, we characterized the microbiota in the porcine proximal colon in response to Trichuris suis (whipworm) infection using 16S rRNA gene-based and whole-genome shotgun (WGS) sequencing. A 21-day T. suis infection in four pigs induced a significant change in the composition of the proximal colon microbiota compared to that of three parasite-naive pigs. Among the 15 phyla identified, the abundances of Proteobacteria and Deferribacteres were changed in infected pigs. The abundances of approximately 13% of genera were significantly altered by infection. Changes in relative abundances of Succinivibrio and Mucispirillum, for example, may relate to alterations in carbohydrate metabolism and niche disruptions in mucosal interfaces induced by parasitic infection, respectively. Of note, infection by T. suis led to a significant shift in the metabolic potential of the proximal colon microbiota, where 26% of all metabolic pathways identified were affected. Besides carbohydrate metabolism, lysine biosynthesis was repressed as well. A metabolomic analysis of volatile organic compounds (VOCs) in the luminal contents showed a relative absence in infected pigs of cofactors for carbohydrate and lysine biosynthesis, as well as an accumulation of oleic acid, suggesting altered fatty acid absorption contributing to local inflammation. Our findings should facilitate development of strategies for parasitic control in pigs and humans.

Comparative morphological, biometrical and molecular studies of Trichuris discolor isolated from Bos taurus from Spain and Iran was carried out. Furthermore, Trichuris ovis isolated from B. taurus and Capra hircus from Spain has been, molecularly, analyzed. Morphological studies revealed clear differences between T. ovis and T. discolor isolated from B. taurus but differences were not observed between populations of T. discolor isolated from different geographical regions. Nevertheless, the molecular studies based on the amplification and sequencing of the internal transcribed spacers 1 and 2 ribosomal DNA and 16S partial gene mitochondrial DNA showed clear differences between both populations of T. discolor from Spain and Iran suggesting two cryptic species. Phylogenetic studies corroborated these data. Thus, phylogenetic trees based on ITS1, ITS2 and 16S partial gene sequences showed that individuals of T. discolor from B. taurus from Iran clustered together and separated, with high bootstrap values, of T. discolor isolated from B. taurus from Spain, while populations of T. ovis from B. taurus and C. hircus from Spain clustered together but separated with high bootstrap values of both populations of T. discolor. Furthermore, a comparative phylogenetic study has been carried out with the ITS1and ITS2 sequences of Trichuris species from different hosts. Three clades were observed: the first clustered all the species of Trichuris parasitizing herbivores (T. discolor, T. ovis, Trichuris leporis and Trichuris skrjabini), the second clustered all the species of Trichuris parasitizing omnivores (Trichuris trichiura and Trichuris suis) and finally, the third clustered species of Trichuris parasitizing carnivores (Trichuris muris, Trichuris arvicolae and Trichuris vulpis)., (Copyright © 2011 Elsevier B.V. All rights reserved.)

The objectives of this study were to determine the prevalence and risk factors for intestinal parasite infection in goats raised in Nakhon Pathom Province. Fecal samples from 190 goats in 12 herds were collected per rectum. Questionnaires focusing on the general information about the farm and farmers, and management practices on farms were completed. Modified McMaster counting technique was performed to detect eggs of intestinal parasites. Each egg found was classified into three groups of parasites based on its characteristics. Individual and herd prevalence were calculated. Multiple logistic regressions were performed to analyze risk factors of infection. Herd prevalence of intestinal parasite infection was 100%, while individual prevalence was 79.47%. Strongyle group was the most common intestinal parasite found in this study. Moniezia spp. (8/190) and Trichuris spp. (1/190) were also found. The average number of eggs found was 1,176 eggs per gram of feces. Risk factors for intestinal parasite infection were housing system, deworming interval, and type of goat in herd. Goats housed in groups had higher infection rates compared with goats housed individually (odds ratio (OR) = 6.34; P value = 0.009). Goats in herds in which anthelmintic drugs were administered in intervals of greater than 3 months were more likely to become infected with intestinal parasites (OR = 33.07; P value <0.001). Goats in herds that kept only dairy goats were less likely to become infected than herd that kept only meat goats or kept both dairy and meat goats (OR = 46.20 and 8.75; P value <0.001 and 0.011, respectively).

We conducted cross-sectional surveys of parasites infecting a large free-living colony of baboons at the Southwest National Primate Research Center in San Antonio in October 2003 and April 2004, immediately before, and 6 mo after, treatment with ivermectin. Trichuris sp. was the predominant species present, infecting 79 and 69% of individual animals in the 2 surveys, with fecal egg counts (FEC) of up to 60,200 eggs per g (epg) (mean = 1,235 in October 2003 and 1,256 in April 2004). Prevalence remained fairly stable across age groups, and intensity was highest in animals <1 or >15 yr old, in contrast to patterns observed in humans, where school-age children show the heaviest infections. Strongyloides sp. was also identified, but the species identity remains uncertain. Small subunit ribosomal DNA sequences differed from published sequences of Strongyloides fuelleborni at multiple sites, but resided in a monophyletic group with other Strongyloides species with 92% bootstrap support. This may reflect a recent acquisition from a local host, or that the published sequence of S. fuelleborni is incorrect. Widespread infections with 2 nematode genera in a free-ranging baboon colony that are an important source of morbidity in human populations provide a useful model system for work on the epidemiology, control, pathology, and genetics of these parasites in a host species that is physiologically, immunologically, and genetically similar to humans.

Helminth infection in pigs serves as an excellent model for the study of the interaction between human malnutrition and parasitic infection and could have important implications in human health. We had observed that pigs infected with Trichuris suis for 21 days showed significant changes in the proximal colon microbiota. In this study, interactions between worm burden and severity of disruptions to the microbial composition and metabolic potentials in the porcine proximal colon microbiota were investigated using metagenomic tools. Pigs were infected by a single dose of T. suis eggs for 53 days. Among infected pigs, two cohorts were differentiated that either had adult worms or were worm-free. Infection resulted in a significant change in the abundance of approximately 13% of genera detected in the proximal colon microbiota regardless of worm status, suggesting a relatively persistent change over time in the microbiota due to the initial infection. A significant reduction in the abundance of Fibrobacter and Ruminococcus indicated a change in the fibrolytic capacity of the colon microbiota in T. suis infected pigs. In addition, ∼10% of identified KEGG pathways were affected by infection, including ABC transporters, peptidoglycan biosynthesis, and lipopolysaccharide biosynthesis as well as α-linolenic acid metabolism. Trichuris suis infection modulated host immunity to Campylobacter because there was a 3-fold increase in the relative abundance in the colon microbiota of infected pigs with worms compared to naïve controls, but a 3-fold reduction in worm-free infected pigs compared to controls. The level of pathology observed in infected pigs with worms compared to worm-free infected pigs may relate to the local host response because expression of several Th2-related genes were enhanced in infected pigs with worms versus those worm-free. Our findings provided insight into the dynamics of the proximal colon microbiota in pigs in response to T. suis infection.

The whipworm, Trichuris trichiura, causes trichuriasis in ∼600 million people worldwide, mainly in developing countries. Whipworms also infect other animal hosts, including pigs (T. suis), dogs (T. vulpis) and non-human primates, and cause disease in these hosts, which is similar to trichuriasis of humans. Although Trichuris species are considered to be host specific, there has been considerable controversy, over the years, as to whether T. trichiura and T. suis are the same or distinct species. Here, we characterised the entire mitochondrial genomes of human-derived Trichuris and pig-derived Trichuris, compared them and then tested the hypothesis that the parasites from these two host species are genetically distinct in a phylogenetic analysis of the sequence data. Taken together, the findings support the proposal that T. trichiura and T. suis are separate species, consistent with previous data for nuclear ribosomal DNA. Using molecular analytical tools, employing genetic markers defined herein, future work should conduct large-scale studies to establish whether T. trichiura is found in pigs and T. suis in humans in endemic regions.

Previous studies addressing the importance of host gender in parasite transmission have shed light on males as the more important hosts, with the higher transmission potential of males being explained by the fact that they often harbour higher parasite loads than females. However, in some systems females are more heavily infected than males and may be responsible for driving infection under such circumstances. Using a wild population of common voles (Microtus arvalis), we showed that females were more frequently infected by the intestinal nematode Trichuris arvicolae than males (i.e. prevalence based on the presence of eggs in the faeces) and that females were shedding greater numbers of parasite eggs per gram of faeces (EPG) than males. By applying an anthelmintic treatment to either male or female voles, we demonstrated that treating females significantly reduced parasite burdens (i.e. prevalence and EPG) of both male and female hosts, while treating males only reduced parasite burden in males. These findings indicate that in this female-biased infection system females play a more important role than males in driving the dynamics of parasite transmission., (Copyright © 2011 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved.)

Previously, we reported a tick recovered from Antelope Cave in extreme northwest Arizona. Further analyses of coprolites from Antelope Cave revealed additional parasitological data from coprolites of both human and canid origin. A second tick was found. This site is the only archaeological locality where ticks have been recovered. We also discovered an acanthocephalan in association with Enterobius vermicularis eggs in the same coprolite. This association shows that the coprolite was deposited by a human. This discovery expands our knowledge of the range of prehistoric acanthocephalan infection. In addition, findings from canid coprolites of Trichuris vulpis are reported. This is the first published discovery of T. vulpis from a North American archaeological context. The close association of dogs with humans at Ancestral Puebloan (Anasazi) sites raises the potential that zoonotic parasites were transferred to the human population. The archaeological occupation is associated with the Ancestral Pueblo culture 1,100 yr ago.

Canine atopic dermatitis is a common disease and is considered as an animal model of the human disease. Immunomodulation by helminths is reported in several species. The aim of this study was to determine whether nematodes have an immunomodulatory effect on atopic dermatitis in dogs. In the pilot study, 12 atopic dogs were infected with either embryonated eggs of Trichuris vulpis (500 and 2500 eggs in 3 dogs each) or L3 larvae of Uncinaria stenocephala (100, 500 and 2500 eggs in 2 dogs each), respectively, for 3 months. Pruritus was evaluated with visual analogue scales and clinical lesions with the canine atopic dermatitis extent and severity index (CADESI). Skin biopsies were obtained for histopathology at the beginning and end of the study. In the subsequent placebo-controlled, double-blinded, randomised study, 21 dogs received either 2500 embryonated T. vulpis eggs or placebo and were evaluated similarly. In addition, allergen-specific serum IgE concentrations were determined. All dogs in the pilot study improved in their lesion scores, most in their pruritus scores. The cutaneous inflammatory infiltrate did not change significantly. In the subsequent randomised study, there was no significant difference between placebo and Trichuris administration in regard to pruritus or CADESI. IgE concentrations also did not change significantly. Infection with T. vulpis did not significantly change clinical signs of canine atopic dermatitis., (Copyright © 2011. Published by Elsevier B.V.)

Species of Trichuris (Nematoda:Trichuridae) parasitize a broad range of mammalian hosts. To date, 21 Trichuris species infecting nine families of rodents have been found in North and South America. Trichuris navonae n. sp. is described on the basis of specimens recovered from a species of forest-dwelling mice, Akodon montensis (Cricetidae: Sigmodontinae), from nine localities of Misiones Province, Argentina. A comparison with all the species of Trichuris from North and South American rodents is given. The separation of the new species of Trichuris is based on morphologic and morphometrica features, such as the absence of a spicular tube, the presence of a cylindrical spicular sheath with sharp spines, a non-protrusive vulva, a long anterior-posterior portion of the body, a lengthy spicule, and a proximal and distal cloacal tube. This is the third record of this genus in rodents of the Sigmodontinae from Argentina and the fifth record from South American rodents. Despite the large number of potential host species, only about 1.9% of sigmodontine rodent species have been reported as hosts of Trichuris spp. It is suggested that this number represents but a small fraction of Trichuris spp. that occur in sigmodontine rodents, and that additional survey of this group should yield additional species.

Tryptophan catabolism via the kynurenine pathway is dependent on the enzyme Indoleamine 2,3-dioxygenase (IDO). Expression of IDO is upregulated in a number of inflammatory settings such as wounding and infection, and the resulting local tryptophan depletion may inhibit the replication of intracellular pathogens. Indo gene expression is upregulated in the gut during chronic infection with the mouse whipworm Trichuris muris. We demonstrate an increase in the rate of colonic epithelial cell turnover after inhibition of IDO in T. muris-infected SCID mice, leading to a significant expulsion of parasite burden. We identify the goblet cell as a novel source of IDO and present data revealing a new role for IDO in the regulation of epithelial cell turnover post-infectious challenge., (© 2011 Blackwell Publishing Ltd.)

Trichuris thrichomysi n. sp., recovered from the cecum of the wild rodent Thrichomys apereoides from a transition zone between the Atlantic Forest and Cerrado morfoclimatic domains, and its life cycle observed under experimental conditions are described. This new species is closely related to Trichuris travassosi, Trichuris chiliensis and Trichuris fulvi, but can be distinguished from them mainly by differences in the posterior end of males. Details of the surface such as the bacillary gland, cuticular inflations and several morphological details obtained by scanning electron microscopy and field emission scanning electron microscopy confirmed the characteristics that differentiate the new species. The histopathology of the intestinal wall of naturally infected rodents is also reported. The present study extends the geographical distribution of T. thrichomysi n. sp to the Pantanal ecosystem and reports a new host, Thrichomys pachiurus., (Copyright © 2010 Elsevier B.V. All rights reserved.)

Trichuris vulpis, the dog whipworm, causes an intestinal parasitosis of relevance in current canine veterinary practice. Its occurrence is well-known in pets, kennelled dogs and stray animals, and its eggs contaminate the ground in urban areas all over the world. Moreover, T. vulpis has been occasionally incriminated, though not convincingly substantiated, as a cause of zoonosis. This nematode is erroneously considered an "old-fashioned" pathogen with a consequent lack of up- to- date knowledge on several aspects of the infection. These, in turn, are still controversial and need to be studied in greater depth. This article reviews current knowledge of T. vulpis, together with a discussion of critical points in epidemiology, zoonotic hazard, diagnosis and treatment of canine trichurosis.

A phylogeographic study was carried out of Trichuris muris, nematode parasitizing Murinae rodents from the Muridae family, isolated from four different hosts and from different geographical regions of Europe by amplification and sequencing of the ITS1-5.8S-ITS2 fragment of the ribosomal DNA. T. muris was found in the Apodemus sylvaticus, Apodemus flavicollis, Mus domesticus, and Rattus rattus rodents. The molecular results confirm the presence of DNA polymorphisms among T. muris isolates from Europe. The present study shows two clear-cut geographical and genetic lineages: one of them is widespread from northern Spain (Catalonia) to Denmark (Western European region), while the second is widespread in the Eastern European region (Croatia, Rumania, and Turkey). These two genotypes can be easily distinguished by a PCR-RFLP analysis of this sequence with the ApalI restriction enzyme. Moreover, networks and phylogenetic reconstructions also reveal that T. muris from various Murinae rodents did not differentiate according to the host species that they parasitize. Furthermore, T. muris isolated from The Canary Islands revealed a typical haplotype (H6) only present in The Canary Islands and not in continental Europe. It is suggested that one haplotype from La Gomera Island is the ancestor of T. muris in the Canary Islands.

Although there is a growing recognition that the transfer of diseases between humans and non-human primates can be of great significance for conservation biology, there have been only a few studies focusing on parasites. In this study, saddleback (Saguinus fuscicollis) and moustached tamarin (Saguinus mystax) from the rainforest of the Peruvian lowlands were used as models to determine helminth parasite associations between canopy-dwelling primate species and a nearby human settlement. The human population showed high prevalences of infestation with a number of nematodes, including Ascaris lumbricoides (88.9%), Trichuris trichiura (37%) and hookworms (55.6%). However, the ova of these geohelminths were not detectable in tamarin faeces. Thus, no direct parasite transfer from humans to non-human primates could be documented. However, tamarin groups with more frequent contact to humans and their facilities had significantly higher prevalences and egg output of Prosthenorchis elegans, an important primate pathogen, than a forest group. In contrast, a cestode was significantly more common with more egg output in sylvatic than in human-associated groups. Human alteration of the habitat is likely to play a major role in determining the occurrence, prevalence and intensity of helminth infestation of wild non-human primates.

In this paper, a morphological and biometrical study by optical microscopy and scanning electronic microscopy (SEM) of Trichuris suis isolated from different hosts (Sus scrofa domestica and Sus scrofa scrofa) and Trichuris trichiura isolated from chimpanzee, has been carried out. Our results demonstrate the existence of typical pericloacal papillae in both species. Biometrical parameters of T. suis and T. trichiura overlapped but males and females of T. trichiura tended to be shorter and thinner than those of T. suis. Our results suggest that T. suis and T. trichiura cannot be differentiated using standard procedures as morphological and biometrical determinations. Thus, the ITS1-5.8S-ITS2 region of the ribosomal DNA was sequenced to allow a differentiation between T. suis and T. trichiura on genetic level. The ITS1 and ITS2 sequences derived from T. trichiura eggs isolated from feces of primates (Colobus guereza kikuyensis and Nomascus gabriellae) showed clear differences to the respective sequences of T. suis derived from eggs of different porcine hosts. The 5.8S gene was similar between the two species. Sequences obtained from different populations of the same species showed no significant differences indicating that the ITS1-5.8S-ITS2 sequences reported in this study are representative for T. trichiura and T. suis, respectively. Phylogenetic relationships have been determined attending to the ITS1 and ITS2 sequences from different species of the genus Trichuris. In conclusion, T. trichiura and T. suis are considered to be closely related but genetically different species. Both species can be easily and reliably distinguished by a PCR-RFLP analysis of the ITS1 and ITS2 sequences with different restriction enzymes.

A coprological survey was performed at a slaughterhouse in Osaka, Japan, from 2004 to 2007 on 129 pigs reared in 8 prefectures, and on 213 cattle reared in 21 prefectures. Eimeria spp., Trichuris suis, Ascaris suum and Metastrongylus spp. infections were found in 52 (40.3%), 32 (24.8%), 19 (14.7%) and 3 pigs (2.3%), respectively, while Eimeria spp., Capillaria bovis and Trichuris sp. infections were detected in 163 (76.5%), 15 (7.0%) and 8 cattle (3.8%), respectively. Our results suggest that environmentally resistant oocysts and eggs of parasites could be widespread at the farms examined.

This paper reports on the efficacy of a novel flavoured tablet formulation of emodepside plus praziquantel (Profender tablets for dogs) against mature and immature adult whipworms (Trichuris vulpis) at the proposed minimum dose of 1 mg emodepside and 5 mg praziquantel per kg body weight in dogs. Three randomised, blinded and controlled laboratory studies with naturally or experimentally infected dogs were performed. The first study was conducted as a dose determination study in experimentally infected dogs using three different dose levels, i.e., 0.5x, 1x and 2x the minimum therapeutic dose. Two further studies confirmed the efficacy of emodepside plus praziquantel tablets against mature and immature adult T. vulpis at the recommended minimum dose. In all three studies, the efficacy against mature and immature adult T. vulpis was >99%. No side effects of the treatment were observed. It is concluded that the emodepside plus praziquantel tablet is an effective and safe treatment against mature and immature adult stages of T. vulpis in dogs.

The population dynamics of Trichuris suis in pigs was studied during long-term experimental infections. Twenty-three 10-week-old pigs were inoculated with 5 T. suis eggs/kg/day. Seven, 8, and 8 pigs were necropsied at weeks 4, 8, and 14 post-start of infection (p.i.), respectively. The median numbers of worms in the colon were 538 (min-max: 277-618), 332 (14-1140) and 0 (0-4) at 4, 8, and 14 weeks p.i. respectively, suggesting an increased aggregation of the worms with time and acquisition of nearly sterile immunity. The serum levels of T. suis specific antibodies (IgG1, IgG2 and IgA) peaked at week 8 p.i. By week 14 p.i. the IgG2 and IgA antibody levels remained significantly elevated above the level of week 0. The population dynamics of T. suis trickle infections in pigs is discussed with focus on interpretation of diagnostic and epidemiological data of pigs, the use of pigs as a model for human Trichuris trichiura infections and the novel approach of using T. suis eggs in the treatment of patients with inflammatory bowel disease.

Aggregated distributions of macroparasites within their host populations are characteristic of most natural and experimental infections. We designed this study to measure the amount of variation that is attributable to host genetic factors in a pig-helminth system. In total, 195 piglets were produced after artificial insemination of 19 sows (Danish Landrace-Yorkshire crossbreds) with semen selected from 13 individual Duroc boars (1 or 2 sows per boar; mean litter size: 10.3; 5-14 piglets per litter). Starting at 10 weeks of age, piglets were repeatedly infected with the gastrointestinal helminths Trichuris suis and Ascaris suum by administering eggs in the feed for 14 weeks until necropsy. Faecal egg counts (FECs) were estimated regularly and A. suum worm burden was obtained at necropsy. Heritability calculations for log (FEC+1) at weeks 7-10 post-infection (p.i.) showed that 0.32-0.73 of the phenotypic variation for T. suis could be attributed to genetic factors. For A. suum, heritabilities of 0.29-0.31 were estimated for log (FEC+1) at weeks 7-14 p.i., whereas the heritability of log worm counts was 0.45. Strong positive genetic correlations (0.75-0.89) between T. suis and A. suum FECs suggest that resistance to both infections involves regulation by overlapping genes. Our data demonstrate that there is a strong genetic component in resistance to A. suum and T. suis infections in pigs. Identification of responsible genes would enhance our understanding of the host immune response to these common nematodes and for the closely related species (T. trichiura and A. lumbricoides) in man infecting more than a billion people.