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Parasitic helminths exhibit remarkable diversity in their life cycles, although few parasite species have their whole life cycles resolved. Owing to the fact that parasite life stages within hosts are often not comparable using morphological data, genetic data provides convincing evidence of transmission pathways between intermediate and definitive hosts. We took this approach to an ecosystem level, genetically matching parasite (acanthocephalan, cestode, nematode and trematode) life stages across a broad taxonomic range of intermediate and definitive hosts (invertebrates, seabirds, elasmobranchs and teleost fish) in Otago's (New Zealand) coastal marine ecosystem. We identified which transmission routes are utilized by the most parasite species and assessed which intermediate hosts are most important in facilitating the transmission of parasites in this ecosystem. Our findings reveal 59 new records of larval parasites infecting their respective intermediate hosts and 289 transmission pathways utilized by 35 helminth species to complete their life cycles. Sprat, triplefin and arrow squid all hosted the highest number of larval parasite species, suggesting they play important roles as intermediate hosts. We then used the new life cycle data to provide a synthetic overview of the life cycles known for various parasite groups in New Zealand. This study highlights how studying parasite life cycles can enhance our understanding of the ecology and evolution of parasites and hosts in natural systems, beyond simply resolving life cycles., (Copyright © 2023 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

Helminth infections have been re-emerging with the growing popularity of free-range and floor-based chicken production systems. The aim of this study was to determine the prevalence and worm burdens of intestinal helminth infection in cage-free laying chickens in Australia. In an online survey about worm prevalence, a high proportion of respondents reported the detection of Ascaridia galli (77%), followed by tapeworms (69%) and caecal worms (Heterakis gallinarum) (62%), whereas fewer respondents (23%) reported the presence of hair worms (Capillaria spp.) in their flocks. Total worm recovery from 407 laying hens on four farms found that 92.1% of hens harboured one or more helminth parasite with a prevalence of 73 to 100% across farms. Mixed infections were common with 79% of hens harbouring two or more helminth species. The prevalence of nematode species H. gallinarum, A. galli and Capillaria spp. was 87, 82 and 35% respectively. Five cestode species were found with a low individual chicken prevalence (Raillietina tetragona 4.7%, Raillietina echinobothrida 3.2%, Raillietina cesticillus 5.2%, Choanotaenia infundibulum 4.4%, and Hymenolepis cantaniana 4.4%). The hens harboured an average of 71 worms with H. gallinarum having the highest mean burden (45.5 worms/hen) followed by A. galli (22.0 worms/hen), Capillaria spp. (2.7 worms/hen) and cestodes (0.8 worms/hen). The sex ratio (female:male worms) was 1.38:1 for A. galli, and 1.77:1 for H. gallinarum. There was a strong positive correlation between A. galli female worm count and excreta egg count (EECs) (r s  = 0.94, P < 0.0001) and also between total nematode worm count and EEC (r s  = 0.82, P < 0.0001) in individual hens. When investigating intestinal excreta (n = 10) and caecal excreta (n = 10) of 16 chicken flocks the prevalence of infection with ascarid worms in intestinal and caecal excreta was 71 and 78% respectively and 27% prevalence of Capillaria spp. in intestinal excreta with mean EECs of 407, 404, and 18 eggs/g of excreta (EPG), respectively. These results suggest that most chickens kept in free-range or floor production systems are infected with one or more helminth parasite species. Heavy worm infections would likely affect the production performance and welfare of birds with adverse economic impact. Strategic or tactical anthelmintic treatment with effective anthelmintic could reduce this impact., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Background: MicroRNAs (miRNAs) are about 22-nucleotide, small, noncoding RNAs that control gene expression post-transcriptionally. Helminth parasites usually express a unique repertoire of genes, including miRNAs, across different developmental stages with subtle regulatory mechanisms., Objective: There is a necessity to investigate the involvement of miRNAs in the development of parasites, host-parasite interaction, immune evasion and their abilities to govern infection in hosts. MiRNAs present in helminth parasites have been summarized in the current systematic review (SR)., Methods: Electronic databases, including PubMed, Scopus, ProQuest, Embase, and Google Scholar search engine, were searched to identify helminth miRNA studies published from February 1993 till December 2019. Only the published articles in English were included in the study., Results: A total of 1769 articles were preliminarily recorded. Following the strict inclusion and exclusion criteria, 105 studies were included in this SR. Most of these studies focused on the identification of miRNAs in helminth parasites and/or probing of differentially expressed host miRNA profiles in specific relevant tissues, while 12 studies aimed to detect parasite-derived miRNAs in host circulating system and 15 studies characterized extracellular vesicles (EV)-derived miRNAs secreted by parasites., Conclusion: In the current SR, information regarding all miRNAs expressed in helminth parasites has been comprehensively provided and the utility of helminth parasitesderived miRNAs in diagnosis and control of parasitic infections has been discussed. Furthermore, functional studies on helminth-derived miRNAs have also been presented., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Introduction: : Human infections with helminth worm parasites are extraordinarily prevalent across tropical and subtropical parts of the world, and control relies primarily on drugs that offer short-term suppression of infection. There is an urgent need for new vaccines that would confer long-lived immunity, protecting children in particular and minimizing community transmission., Areas Covered: : This article discusses the development of helminth vaccines, from the first successful veterinary vaccines that demonstrated the feasibility of inducing protective immunity to helminths, to more recent initiatives to test human helminth antigens. The field has focussed primarily on evaluating individual antigens that could constitute targets amenable to antibody attack to inhibit parasite establishment. In a new direction, vaccines employing extracellular vesicles released by helminths have also given exciting results., Expert Opinion: : Taking into account the complex life cycles and sophisticated immune evasion strategies of many helminths, a combination of antigens and approaches designed to target essential functional pathways of the parasite will be required to achieve a high level of protection in future anti-helminth vaccines.

Gastrointestinal helminth parasites are a concern for the poultry industry worldwide as they can affect the health, welfare, and production performance. A systematic review of the prevalence over time in different countries may improve our understanding of gastrointestinal helminthiasis in chickens and subsequently lead to improved poultry health. The aim of this systematic review and meta-analysis was to provide an overview of the published information regarding the epidemiology and the diagnostic approaches of chicken helminth infection. Six databases were searched for studies, and a total of 2,985 articles published between 1942 and 2019 were identified and subsequently screened for eligibility using title or abstract and full text assessment, resulting in 191 publications to be used in the study. Postmortem diagnostics (73.8%) and the flotation technique (28.8%) were commonly used to detect helminth infections with a pooled prevalence of 79.4% ranging from 4 to 100%. More than 30 helminth species in chicken populations were identified including Ascaridia galli (35.9%), Heterakis gallinarum (28.5%), Capillaria spp. (5.90%), and Raillietina spp. (19.0%) being the most prevalent. The reported prevalence of helminth infection decreased over time in developing countries while it increased in the developed world. Chicken kept in backyard and free-range systems had a markedly higher pooled prevalence of helminth infection (82.6 and 84.8%, respectively) than those housed in cage production systems (63.6%). This may indicate the need for more rigorous control and prevention measures in free-range and backyard production systems using regular deworming coupled with access to early and accurate diagnosis allowing for early intervention., (Copyright © 2021 The Authors. Published by Elsevier Inc. All rights reserved.)

Gastrointestinal parasites of chickens are prevalent in many parts of the world including Ethiopia. This study was conducted with backyard chickens in Ambo, Holeta and, Dire Inchini in the West Shoa zone with the objectives of estimating the prevalence of gastrointestinal helminth infections, identifying the species present and determining associated risk factors. A cross-sectional study was conducted using 252 chickens purchased from local markets. Chickens were killed humanely and gastrointestinal tracts were examined for adult helminths. Identification of the helminths was performed using morphology and microscopy. The overall prevalence of helminth parasites in chickens was 92.1% (232/252) [95% confidence interval (CI): 88.0% - 95.1%]. 80.2% (204/252) [95% CI: 75.3% - 86.9%] and 77.8% (196/252) [95% CI: 72.1% - 82.8%] of chickens were infected with diverse nematode and cestode species, respectively. Parasitological examination revealed the presence of three nematode and five cestode species. Ascaridia galli (69.8%) and Heterakis gallinarum (13.5%) were the dominant nematode species and Railletina tetragona (54.0%) and Railletina echinobothrida (46.8%) were the most prevalent species of cestodes identified. A significant difference (p < .05) was observed between the prevalence of nematode parasites and sex, age, and origin of the chicken. Similarly, sex and origin of the chickens were significantly different with the prevalence of cestode infections. Higher prevalence was observed in male versus female chickens, in young versus adult chickens and in chickens from Holeta and Direinchin compared to Ambo. In contrast, weight, health status, diarrhea status, and age (for cestodes) were not significantly associated with nematode and cestode infection. In conclusion, the present study detected a high prevalence of diverse types of gastrointestinal helminths in backyard chickens, which could result in poor health and reduce productivity. Therefore, the present study strongly suggests appropriate and strategic control of helminthiasis to improve the health and output of backyard chickens in the study areas., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Approximately one-sixth of the worlds' population is infected with helminths and this class of parasite takes a major toll on domestic livestock. The majority of species of parasitic helminth that infect mammals live in the gut (the only niche for tapeworms) where they contact the hosts' epithelial cells. Here, the helminth-intestinal epithelial interface is reviewed in terms of the impact on, and regulation of epithelial barrier function, both intrinsic (epithelial permeability) and extrinsic (mucin, bacterial peptides, commensal bacteria) elements of the barrier. The data available on direct effects of helminths on epithelial permeability are scant, fragmentary and pales in comparison with knowledge of mobilization of immune reactions and effector cells in response to helminth parasites and how these impact intestinal barrier function. The interaction of helminth-host and helminth-host-bacteria is an important determinant of gut form and function and precisely defining these interactions will radically alter our understanding of normal gut physiology and pathophysiological reactions, revealing new approaches to infection with parasitic helminths, bacterial pathogens and idiopathic auto-inflammatory disease.

It is not uncommon for pigeons kept for entertainment or competition to be infected with a variety of intestinal parasites, including nematodes and cestodes. Infection by these worms is a risk not only to birds but also to native wildlife and humans. The objective of this study is to assess the prevalence of helminth infections in pigeons in Zabol County, Iran, and to develop strategies for the prevention and treatment of these infections. A total of 220 pigeons were examined for the presence of parasites in their gastrointestinal tracts between 2021 and 2022. The pigeons were categorized according to gender, breed, age, medication, and feed type. The digestive tract contents were scraped and washed with warm water in order to collect intestinal helminths. A variety of techniques employed for the isolation, observation, and identification of nematodes and cestodes. Additionally,the parasites around the esophageal tissue were also examined in this study. A total of 96 positive cases of helminth infection (43.63%) were identified in the 220 samples of pigeon gastrointestinal tracts examined. In addition, 52 pigeons exhibited exclusive cestode infections, 14 had nematode infections, and 31 had co-infections. Heterakis gallinarum (H. gallinarum), Eulimdana clava (E. clava), Hadjelia truncate (H. truncate), and Ascaridia columbae (A. columbae) were among the nematodes found. Cestode species identified include Raillietina tetragona (R. tetragona), Raillietina echinobothrida (R. echinobothrida), Raillietina cesticillus (R. cesticillus), Raillietina magninumida (R. magninumida), and Cotugnia digonopora (C. digonopora). A statistical analysis of data revealed a significant correlation between helminth infection and drug consumption (p=0.001). Infection with nematodes and cestodes is also associated with pigeon age (p=0.00001). T Notably, despite the hot and dry conditions, there was a high prevalence of cestode and nematode infestations in pigeons in Zabol, Iran. It is imperative that a comprehensive control program be implemented to prevent parasite transmission to pigeons and the local avian ecosystem. [ABSTRACT FROM AUTHOR]

Biodiversity of vertebrate farm animals like cattle, buffalo, sheep, goat and fowls are playing an important role in the economy of farming industry as well as the economy of the state and in turn the economy of country. Therefore to take care of health and hygiene of all farm animals and related stakeholders in this industry becomes important. By considering this, the present survey work was undertaken at small area level for the Helminths (Gut Parasites) like Nematode, Cestode, Trematodes, Protozoans and Ectoparasites (Arthropods) like lice, ticks and mites. The data obtained from this study is important to literate the farm owners, farmers and other stakeholders about health, hygiene and the impact of this on animals as well as on themselves. The data obtained can also help the stakeholders' to take precautionary step to prevent the animals from getting infected with parasites as well as to provide medical help to animals with the help of farmers. For the present study 12 no of villages were selected from Bhadgaon and Pachora Tahasil from North Maharashtra. From these villages farm animals like buffaloes, cattles, goats, sheeps and fowls were studied for their different types of infections. [ABSTRACT FROM AUTHOR]

Tigerfish (Hydrocynus vittatus Castelnau, 1861) is of considerable importance in both the commercial and recreational fishery activities of Lake Kariba. In our previous paper (Mabika et al. 2019) we provided information on the seasonal occurrence of metazoan parasites of H. vittatus. This communication provides endohelminth infection statistics of male and female H. vittatus across two seasons not previously included. A total of 80 H. vittatus individuals consisting of 56 females and 24 males were examined for endohelminth parasites during the period October 2014–July 2015 in the Sanyati basin, Lake Kariba. Parasites were recovered from the abdominal cavity, mesentery and intestines. Most of the parasites were harboured in the abdominal cavity in both sexes. Parasite infection was more prevalent during the dry season in comparison to the rainy season for both sexes. Contracaecum larval infection was significantly higher in female (84%) than in male tigerfish (24%), whereas larval cestode infections were significantly higher in male tigerfish (59%) than female fish (16%). The mean condition factor of the male tigerfish (1.68) was not significantly higher than that of the female (1.64). The results of the study indicate that female tigerfish were more suitable hosts to Contracaecum larval infection than the male fish. Further parasitological and histopathological research on tigerfish is recommended to contribute to knowledge on endohelminth diversity and conservation. [ABSTRACT FROM AUTHOR]

A full account of the world's species is important for understanding how natural systems are structured, how they function and how they will respond to natural and anthropogenic pressures in the future. Despite the well-known importance of parasites in natural systems, they are too often underrepresented from studies on biodiversity and ecological functioning. In this review, we provide a quantitative synthesis of the current state of knowledge of helminth biodiversity within New Zealand's marine environment. We report that records of parasitic helminths within New Zealand marine animals are few and uneven across host taxa. A large proportion of parasite species are taxonomically unresolved, with some differences across parasite taxa. Few parasites have their whole life cycles resolved, and the majority are only reported from one host species at one life stage. Most endemic host species are yet to be investigated for helminths and there is likely an abundance of endemic parasite diversity yet to be discovered. Host species of greater conservation concern are being investigated for helminths less frequently than species of low conservation concern. We conclude that little is known about parasitic helminths in New Zealand's marine environment and make recommendations on how to improve this situation. [ABSTRACT FROM AUTHOR]

Aim: While most free‐living taxa follow the latitudinal diversity gradient (LDG), or the trend of higher diversity at lower latitudes, we know little about how the diversity of parasitic taxa is distributed across latitudes. To better understand the macroecological patterns of parasite diversity, we sought to determine whether (1) helminths follow the traditional LDG; (2) taxonomic resolution impacts observed patterns; (3) latitudinal patterns are consistent across levels of community organization and (4) helminth diversity is correlated with climate‐ and host‐associated variables. Location: San Juan de Peñas Blancas, Costa Rica; Calnali, Hidalgo, Mexico; College Station, Texas, USA; Brownsville, Nebraska, USA; Winnipeg, Manitoba, Canada; Churchill, Manitoba, Canada Taxon Rodentia: Cricetidae; Nematoda; Platyhelminthes Methods: We sampled parasites from hosts at field sites set approximately every 10° in latitude. We evaluated the relationships between parasite species richness (of all helminths as well as nematodes, cestodes and trematodes separately) and latitude, climate, and host mass at two levels of parasite community organization, the infracommunity and the component community, using generalized additive models. Results: Total helminth richness was significantly correlated with latitude, but the relationship was nonlinear. Nematode, cestode and trematode diversity were also significantly correlated with latitude, but the relationship differed between the levels of community organization and among the taxonomic groups. Climate‐ and host‐associated variables were significantly correlated with different parasite taxa, although the strength and size of the correlations varied among the groups. Main conclusions: There are complex associations between parasite richness and latitude, climate, and host traits, and community organization and taxonomic grouping affected the observed relationships. Climate has been implicated as an important factor in shaping LDG patterns and may similarly influence helminth diversity patterns. Overall, this work provides further support and exceptions to the LDG and stresses the importance of considering scale in ecological investigations. [ABSTRACT FROM AUTHOR]

Members of the Torpedinidae (torpedoes) and Hypnidae (coffin ray) use electric organ discharges (EOD) to stun or kill their prey before consumption. We investigated whether EOD could also negatively affect the helminth larvae infecting these preys through a surrogate model: we applied electric discharges to individuals of blue whiting, Micromesistius poutassou, that harbored live larvae of Anisakis. Larval mortality throughout a 6‐h period was significantly higher in the treatment group, suggesting that EODs could significantly hamper helminth recruitment. We then tested whether torpedinids and hypnids ("strong‐EOD" families) harbored species‐poor helminth (cestode) assemblages compared with "weak‐EOD" Torpediniformes (Narcidae and Narkidae) and other Batoidea. Based on comparisons on estimated species diversity and mean species richness of tapeworms at host individual level we found that (i) Torpediniformes had the lowest tapeworm diversity of all Batoidea orders; (ii) Torpedo spp. consistently had the lowest mean cestode richness at host individual level, and this could not be related to other host factors influencing cestode diversity in chondrichthyans, that is body size, trophic level or dietary breath. However, a preliminary comparison between "strong‐EOD" and "weak‐EOD" Torpediniformes did not detect clear differences of cestode richness. Thus, evidence supporting an unambiguous contribution of EODs to depauperate cestode assemblages requires further research. [ABSTRACT FROM AUTHOR]

The diagnosis of human taeniosis can be achieved through coproscopy, ELISA or PCR. An important limitation of these methods is the high turnaround time for stool sample collection and preparation, indicating the need for a straightforward sampling strategy. Due to the high metabolic activity and reproductive potential of Taenia spp., we hypothesise that parasite DNA (cells and eggs) present in the peri-anal region of the host can be exploited as a target for molecular diagnosis. We evaluated the feasibility of recovering parasite DNA from the peri-anal area of foxes naturally infected with Taenia spp. Before necropsy, cotton swabs were rubbed at the peri-anal region of foxes. DNA was extracted using alkaline lysis coupled with a commercial DNA isolation kit (method A) or alkaline lysis alone (method B). DNA was used in the multiplex-PCR assay (previously described and called here swab-PCR) and a novel LAMP assay detecting Taenia spp. commonly found in foxes (swab-LAMP). The results of these assays from 105 foxes were compared with the presence of intestinal helminths determined at necropsy and by the sedimentation and counting technique (SCT). The sensitivity of swab-PCR for detecting Taenia (n = 68) was 89.8% (95% CI, 77.7–96.6) and 89.5% (66.9–98.7) using methods A and B, respectively. The sensitivity of the swab-LAMP assay was 83.7% (70.3–92.7) using method A and 89.5% (66.9–98.7) with method B. We postulate that peri-anal swab sampling followed by simplified DNA extraction and LAMP might be a suitable strategy for surveillance of human taeniosis in resource-limited settings in the future. [ABSTRACT FROM AUTHOR]

The present study was carried out to investigate the prevalence of gastrointestinal helminths (GI) parasite in goat and its associated determinants (season, age and sex) in Lucknow, Uttar Pradesh. Helminth prevalence was found to be 67.6% in the present research with significantly high nematode infestations (65.1%), followed by trematode (18.3%) andcestode (12.7%).The prevalence rate of different helminth species varied significantly (p ≤ 0.05) and it was reported that the highest infestation rate was found due to Haemonchus sp. (62.3%), followed by Trichuris sp. (56.3%), Oesophagostomum sp. (36.1%), Bunostomum sp. (27.9 %), Paramphistomum sp. (18.3%), and Moneizia sp. (12.7%). A significant (p ≤ 0.05) variation in the prevalence rate was detected during monsoon (84.7%) followed by summer (67.7%) and winter (50.4%). Agewise prevalence indicated younger goats significantly (p ≤ 0.05) more susceptible (87.5%) than adults (51.3%), whereas in case of gender-wise prevalence significant (p ≤ 0.05) difference was observed and it was found that females were more prone to the infestation (74.2%) than males (59.6%). The present study revealed that the seasonal variation with associated determinants plays a prominent role in the prevalence of GI helminths of the animals; hence thereis an urgent need for proper grazing management and routine prophylactic treatment of goat livestock. [ABSTRACT FROM AUTHOR]

Moniezia expansa is common cestode in the small intestine of sheep and causes considerable damage to it. Therefore, an effort to study such biological aspects of Moniezia expansa which would help in its control is much needed. The glycogen content and in vitro consumption of endogenous glycogen was determined in immature, mature and gravid proglottids of Moniezia expansa by Anthrone method by Carroll et al. (1956). The total glycogen (on fresh weight basis) was found to be 3.03%, 4.26% and 3.85% respectively in immature, mature and gravid proglottids of unstarved (control) parasite. The glycogen content in immature, mature and gravid proglottids of parasites starved for 3 hrs. is 2.51%, 3.09% and 2.91% respectively, parasites starved for 6 hrs is 1.91%, 2.0% and 2.0% respectively, parasites starved for 9 hrs. 1.25%, 1.33% and 1.35 respectively and parasites starved for 12 hrs is 0.79%, 0.80% and 0.99% respectively (on fresh weight basis).The endogenous glycogen consumption (in percent of total glycogen content of control parasite) by immature, mature and gravid proglottid was found to be 17.16%, 27.46% 24.42% respectively in parasites starved for 3 hours, 36.96%, 53.05% and 48.05% respectively in parasites starved for 6 hours, 58.75% 68.78% and 64.94% respectively in parasites starved for 9 hours and 73.93%, 81.22% and 74.29% respectively in parasites starved for 12 hours. Rate of consumption of endogenous glycogen between different starvation time periods (in percentage per hour) for immature, mature and gravid proglottids is also calculated. Rate of consumption was maximum during early hours of starvation i.e. between 0-3 hrs and 3-6 hrs and was minimum at 9-12 hrs. Glycogen is the major energy reserve in parasitic helminths which live in low oxygen condition, as they are the best substrate for anaerobic energy production. The study of consumption of endogenous glycogen in cestode during starvation period may be quite helpful for their control in the host. The rate of endogenous glycogen consumption is helpful in understanding metabolic rate and physiological aspects of different proglottids of the parasite. [ABSTRACT FROM AUTHOR]

Aim: This survey was carried out on the carcasses of 29 coyotes from Southeastern Nebraska and Shenandoah area of Iowa to document the helminths present in the intestinal track of these carnivorous animals. Materials and Methods: A total of 29 adult coyote carcasses were generously donated in the autumn and winter (November-February) of 2014-2015 by trappers, fur buyers and hunters of Southeast Nebraska and Shenandoah area of Iowa. The intestine of individual animals were examined for the recovery of helminth parasites as per the established procedures. Results: We found that as many as 93.10% of the investigated coyotes were infected with one or more helminth infections. A total of 10 different species of helminth parasites were recovered from the intestines of coyotes under investigation. Among the 10 species of helminths, 5 were identified as cestodes while the remaining 5 were nematodes. A total of 82.75% of the animals were infected with one or more species of nematodes, while 75.86% of them were colonized with one or more species of cestode parasites. The most abundant species in coyotes were Toxascaris leonina (68.95%) closely followed by Taenia hydatigena (58.62%). The prevalence of Ancylostoma caninum and Taenia pisiformis were recorded at 31.03%, followed by those of Toxocara canis and Echinococcus spp. at 24.13%, respectively. Three animals were infected with Trichuris vulpis while three other coyotes each were found to be harboring Uncinaria stenocephala, Dipylidium caninum, or Hymenolepis diminuta. The presence of H. diminuta might have been the result of the ingestion of a rodent by the respective coyotes. Conclusion: From the overall analysis of the present data and comparing it with the previous reports of various scientists over several decades, we can conclude that intestinal helminths are still very much prevalent among the coyote population in the Southeast Nebraska and Iowa area. The relatively high prevalence of the zoonotic parasite species further warrants a more comprehensive investigation with larger numbers of wild predators from the region to ascertain the possible contribution of coyotes to the disease cycle as these animals are more frequently spotted in and around the densely populated urban areas.

Cephalopods, an appreciated seafood product, are common hosts of marine cestodes. The aim of this work is to report visible alive plerocercoids in longfin inshore squid (Doryteuthis pealeii), a cephalopod species commercialized as fresh and whole in Italy. Seventy D. pealeii from the Northwest Atlantic (FAO area 21) were collected and visually inspected. In total, 18 plerocercoid larvae were found in the viscera of 10 host specimens (P: 14.3% 95% CI 7.1–24.7; MI: 1.8, MA: 0.26; range 1–4) and molecularly analyzed targeting the variable D2 region of the large subunit (LSU) rRNA gene and the cytochrome c oxidase subunit I (COI) gene. The molecular characterization allowed to identify all the plerocercoids as Clistobothrium sp., a cestode of the Phyllobothriidae family with Lamnidae sharks as definitive hosts, and cephalopods as second intermediate hosts. These findings represent the first molecular record of Clistobothrium sp. in D. pealeii, thus contributing to elucidate its poorly known life cycle. Even if not affecting consumer’s health, these visible parasites may represent a reason for disgust for consumers. Therefore, the results suggest that Food Business Operators should also check for the presence of these visible parasites during inspection and underline the importance of a correct consumers’ education.

Parasitic helminths have evolved strategies to evade their host's immune systems. Particularly, the early time of interactions between helminths and their hosts might be decisive for their infection success. We used the cestode Schistocephalus solidus, and its highly specific second intermediate host, the three‐spined stickleback (Gasterosteus aculeatus) to investigate parasite infection and host cellular immune responses starting 1 day postexposure (dpe). We recovered live parasites from stickleback body cavities already 24 hr after exposure. Infection rates increased up to 50% and did not change from 4 dpe onwards. Thus, not all parasites had reached the body cavity at the early time points and clearance of the parasite at later time points did not occur. Stickleback head kidney leucocytes (HKLs) did not show distinct signs of activation and lymphocyte proliferation, granulocyte‐to‐lymphocyte ratios and respiratory burst activity of infected sticklebacks did not deviate from controls significantly. The immune system was activated only late, as indicated by an increase in the total count of HKL relative to stickleback weight (HKL per mg fish), which was significantly elevated in infected fish 32 dpe. S. solidus seems to evade leucocyte activity early during infection facilitating its establishment in the hosts' body cavity. [ABSTRACT FROM AUTHOR]

In this study, we assessed the helminth fauna of seventy two Valentin's Lizard, Darevskia valentini (32♂♂, 35♀♀, 5 subadult). Specimens collected from Kayseri, Ardahan and Van Provinces in Turkey. As a result of the present study, it was detected that forty one hosts are infected with one or more species of helminth. Two species of Cestoda, Oochoristica tuberculata and Mesocestoides spp., and 5 species of Nematoda, Spauligodon aloisei, Skrjabinodon alcaraziensis, Skrjabinodon medinae, Skrjabinelazia hoffmanni and Strongyloides darevsky were found in the hosts. D. valentini represents a new host record for all helminths recorded. Skrjabinodon alcaraziensis is recorded for the fi rst time from Turkey. Van, Kayseri and Ardahan are new locality records for all helminths from D. valentini. [ABSTRACT FROM AUTHOR]

Summary: Small mammals are important reservoirs of zoonotic diseases and are definitive hosts for medically important parasitic helminths. Several rodent and shrew species are peridomestic, bringing them into close contact with both humans and the intermediate hosts that maintain the transmission cycle. Here, we screened DNA extracted from large intestine tissue homogenate from 108 individuals comprised of 10 species. We detected two species known to infect humans, Dicrocoelium dendriticum and Moniliformis moniliformis. We also report the first detection of a second Angiostrongylus species in Singapore. This study demonstrates the diversity of helminths that are parasitizing the small mammals in Singapore. [ABSTRACT FROM AUTHOR]

The seal tapeworm Diphyllobothrium tetrapterum (von Siebold, 1848) Baer, 1932 (syn. Diplogonoporus tetrapterus) is exceptional among cestodes because it possesses two types of the strobila, one with a multiple set of genitalia per proglottid and another with a single set of reproductive organs per proglottid. In this study, Diph. tetrapterum is redescribed on the basis of extensive, well-fixed material from the northern fur seal ( Callorhinus ursinus (Linnaeus, 1758)) from Alaska, USA. A critical morphological and molecular study of comprehensive material from several hosts throughout the Northern Hemisphere is provided. As a result, Diplogonoporus mutabilis Belopolskaia, 1960 and Diplogonoporus violettae Yurakhno, 1986 become junior synonyms of Diph. tetrapterum. Our study provides evidence of intraspecific and even individual variability of Diph. tetrapterum in the number of genital complexes, thus making this generic feature questionable for circumscription of the diphyllobothriid genera. The seal tapeworm has been found exclusively in the Northern Hemisphere and exhibits a wide (euryxenous) specificity at the level of the definitive host, having been found in a number of seals, the sea otter ( Enhydra lutris (Linnaeus, 1758)), and exceptionally, in other terrestrial mammals. Plerocercoids of Diph. tetrapterum are reported from the second (fish) intermediate host for the first time, in this case the pink salmon ( Oncorhynchus gorbuscha (Walbaum, 1792)) from Alaska. [ABSTRACT FROM AUTHOR]

Infection with parasitic helminths can ameliorate the severity of concomitant inflammatory disease. To use the tapeworm, Hymenolepis diminuta, and to extend this concept by assessing whether triggering a memory response against the worm inhibits dinitrobenzene sulphonic acid ( DNBS)-induced colitis in Balb/c mice. Initial studies revealed that oral infection with 1, 3 or 5 H. diminuta cysticercoids 8 days before intrarectal administration of DNBS (3 mg) resulted in less severe inflammation and that infected mice displayed an increased propensity for T helper-2 immunity. A 1 mg dose of a PBS-soluble extract of the worm ( HdAg) delivered intraperitoneally concomitant with DNBS was anticolitic as determined by macroscopic and histological disease scores 72 hour post- DNBS. Mice infected 28 days previously had a memory response as determined by HdAg-evoked increases in interleukin ( IL)-4 and IL-10 from in vitro stimulated splenocytes and serum anti- H. diminuta IgG. Moreover, mice infected with 5 H. diminuta 28 days previously were protected from DNBS-induced colitis by secondary infection or 100 μg HdAg (ip.) at the time of DNBS treatment. An additional approach to managing inflammatory disease could be infection with H. diminuta followed by eliciting antiworm recall responses. [ABSTRACT FROM AUTHOR]

The non-native Asian fish tapeworm Bothriocephalus acheilognathi was registered for the first time in 2008-2009 in a threatened Mexican fish Profundulus candalarius. From June 2008 to April 2009 the overall prevalence of the cestode in the fish intestines was around 35% (N = 242 P. candalarius examined). Unstrobilized and inmature cestodes formed the greatest proportion (91.07%) of the parasite population. Neither the prevalence, nor the mean intensity varied significantly with host sex. Smaller fish (10-29 mm) were parasitized more frequently than medium size fish (30-59 mm), prevalence 43.5% vs 27.3%. Although, the cestodes' monthly prevalence and mean intensity per host varied from 18 to 70 percent and from 2.75 to 9.27 respectively, no significant seasonal difference was found. There was a continuous recruitment of cestodes within the host population, as well as a nearly continuous growth and maturation of the parasites to adults. Most cestodes are lost from the host as development of parasites proceeds, and only 12 of the 437 collected tapeworms reached gravidity. The most important features of the data presented here include the confirmation that B. acheilognathi can reproduce in Mexico. [ABSTRACT FROM AUTHOR]

The purpose of the research was to study helminthofauna of fish Cypriniformes order in comparative aspect in artificial and natural water bodies and the clarification ways of formation of faunal assemblages and development of scientific bases of prevention of helminthiasis of fish. An extensive and systematic research of helminthofauna of fish water bodies of the order Cypriniformes of the northeast of Uzbekistan has realized and taxonomic and faunal analysis of detected parasites has also been carried out. Fauna of parasitic worms of Cypriniformes in ponds of diverse Syrdarya river shows 49 species, 18 species belongs to the class Trematoda, Cestoda class represents 13 species, class Acanthocephala 4 species and the class Nematoda 14 species. Analysis of biological properties and ecological specialty of Cypriniformes parasitic worms allows three types of helminth communities: 25 species parasitizing Cypriniformes as definitive hosts; 19 species parasitizing as intermediate hosts and 6 species parasitizing as a reservoir (paratenetic) hosts. Dioctophyme renale was registered first time in roach for the water bodies of the Syrdarya river. Ordinary carp, in our research, according to as host a new host Nematode of the Raphidascaris acus larvae. On the basis of factual data the environmental factors of the quantitative and qualitative composition of cyprinids helminthofauna in the northeast of Uzbekistan is reported. [ABSTRACT FROM AUTHOR]

Pyruvate kinase (PK; EC 2.7.1.40) and phosphoenolpyruvate carboxykinase (PEPCK; EC 4.1.1.32) are essential regulatory enzymes of glucose oxidation in helminths, the PK/PEPCK branch point being the first divergent step between carbohydrate catabolism of the parasites and their hosts. Recently, PEPCK from the cestode parasite, Raillietina echinobothrida , has been purified and characterized. In order to find out the differential kinetics, if any, at PK/PEPCK branch point in the parasite, in this study, we purified and characterized the parasite PK and compared it with the parasite PEPCK. The purified PK displayed standard Michaelis–Menten kinetics with K m app of 77.8 µM for its substrate PEP, whereas the K m app was 46.9 µM for PEPCK. PEP exhibited differential kinetics at PK/PEPCK branch point of the parasite and behaved as a homotropic effector for PEPCK, but not for PK. The inhibitory constant ( K i) for genistein and daidzein (phytochemicals from Flemingia vestita ) was determined and discussed. From these results, we hypothesize that PK/PEPCK branch point is a probable site for anthelmintic action. [ABSTRACT FROM AUTHOR]

Serine proteases form one of the most important families of enzymes and perform significant functions in a broad range of biological processes, such as intra- and extracellular protein metabolism, digestion, blood coagulation, regulation of development, and fertilization. A number of serine proteases have been identified in parasitic helminths that have putative roles in parasite development and nutrition, host tissues and cell invasion, anticoagulation, and immune evasion. In this review, we described the serine proteases that have been identified in parasitic helminths, including nematodes (Trichinella spiralis, T. pseudospiralis, Trichuris muris, Anisakis simplex, Ascaris suum, Onchocerca volvulus, O. lienalis, Brugia malayi, Ancylostoma caninum, and Steinernema carpocapsae), cestodes (Spirometra mansoni, Echinococcus granulosus, and Schistocephalus solidus), and trematodes (Fasciola hepatica, F. gigantica, and Schistosoma mansoni). Moreover, the possible biological functions of these serine proteases in the endogenous biological phenomena of these parasites and in the host-parasite interaction were also discussed. [ABSTRACT FROM AUTHOR]

Organisms with complex life cycles occupy distinct niches as larvae and adults. One presumed advantage of this is the ability to exploit different resources successively throughout ontogeny. Various taxa, however, have evolved nonfeeding, nongrowing adult stages. We show theoretically that this counterintuitive no-growth strategy is favored when the optimal larval size is greater than or equal to the optimal adult size for reproduction. We empirically investigated this in a group of parasitic worms (helminths). Helminths are transmitted trophically between hosts before reproducing in large, high-trophic-level hosts, and most undergo considerable growth as adults in their final host. Some well-studied tapeworm species (Schistocephalus, Ligula, and Digramma species) are notable exceptions; they reproduce semelparously without any growth in their final habitat (the gut of piscivorous birds). Using cross-species comparative analyses, we show that these tapeworms that do not grow in their final host (1) attain larval sizes in their last intermediate host (fishes) that are comparable to or larger than the adult sizes reached by tapeworms that do grow in the same adult niche (also piscivorous birds) and (2) are large, even as larvae, relative to the mass of their final hosts. These results are consistent with the idea that a massive larval size can make adult growth superfluous, and we discuss whether this likely applies to other complex life cycle taxa with nonfeeding, nongrowing adults. [ABSTRACT FROM AUTHOR]

The article presents a case study of a male cougar (Puma concolor) with Taenia omissa parasite found in the gastrointestinal tract of a Cougar from Manitoba, Canada. The cougar was skinned and his carcass was examined for helminth (parasitic worm) infection. Fifteen adult cestodes (tapeworms) were found and their rostellum was sliced off to observe the hooks using microscope. Seven nematodes were also found having digitiform tails with spicules.

The article discusses a research study on rats (Ratus Norvegicus) in the Belgrade area infected with intestinal helminths and the effect of age, sex and habitat. Captured for the study were 302 rats from various urban, rural and suburban sites in the Belgrade area and fed with water and commercial rodent feed then euthanized using barbiturate anesthesia overdose and the data on their weight, body length and sex were noted after which subjects underwent parasitological procedures and their intestines, colon and secum opened for helminth parasite examination. Results showed high infection prevalence of rats in Belgrade with intestinal helminths that were higher among male than female rats which are noted to be due to larger bodies of males and their larger territories.

Abstract: Cell cultures of parasitic helminths are an invaluable tool for investigations of basic biological processes, as well as for development of improved chemotherapeutic agents and molecular interactions between host and parasite. We carried out a simple and efficient methodology to isolate Echinococcus granulosus germinal cells which were maintained for at least 4months while cultivated in the presence of reducing agents and hormones. Microscopic analysis of the primary cell culture revealed the presence of cells with similar Echinococcus germinal cell morphology and behaviour. Population doubling time was estimated at 48h, showing a rapid division rate. To discard possible host contamination, the specificity of the primary culture was tested by nested PCR, analyzing mdh gene expression and obtaining only one product with the expected size. We also studied the expression of specific E. granulosus proteins in primary cell culture. The novel and systematized method described here constitutes a powerful tool for investigations in cystic echinococcosis on biochemical and biological aspects related to the life cycle of the parasite and mechanisms of host–parasite interactions. This method also constitutes a powerful tool for the design of more efficient therapeutic alternatives. [Copyright &y& Elsevier]

Abstract: We conducted a cross-sectional study from December 2004 to February 2005 and from June 2005 to August 2005. The study aimed to determine the prevalence of gastrointestinal and tracheal helminthes among local chickens in northern Jordan. A total of 208 male and female local scavenging chickens were selected randomly. We examined the trachea and gastrointestinal tract of each bird for the presence of helminthes. We recovered three nematode and eight cestode species. No trematodes were found. One hundred and fifty-two birds (73.1%) (95% CI: 67, 79) were infected. The prevalences of different species were as follows: Ascaridia galli female 28%, male 43%; Capillaria obsignata 0.5%; Heterakis gallinarum 33%; Amoebotaenia cuneata 4.3%; Choanotaenia infundibulum female 23%, male 13%; Davainea proglottina 1.4%; Hymenolepsis cantaniana 11%; Hymenolepsis carioca female 35%, male 24%; Raillietina cesticillius female 5%, male 11%; Raillietina echinobothrida 16%; and Raillietina tetragona 18%. The prevalences of A. galli and R. cesticillus were higher in male than female hosts while those of C. infundibulum and H. carioca were higher in females. The median worm burden was 7 (range 0–168) worms per chicken. [Copyright &y& Elsevier]

Host immunocompetence assessed by spleen size and response to phytohaemagglutinin (PHA) injection may give some indications on the control of parasite infection and on host mediation effect, through immunity, on parasite community structure. We investigated the helminth community and immunocompetence of the white-toothed shrew in a small area to test the relationship between immunocompetence and intensity of helminth infection. At the proximate level and if spleen mass and PHA response reflect the level of immunocompetence, we expected that individuals with a large spleen or a high PHA response should harbour a lower parasite load than individuals with relatively small spleen or low PHA response. In addition, we predicted that the structure of the helminth community should be mediated by the host’s immune defence. Spleen mass was linked to helminth infection. Nematodes and cestodes were negatively associated within hosts. PHA response was not related to total helminth intensity of infection but was negatively related to cestode intensity and positively to nematode intensity. This result suggests either a differential modulating effect on immunity by the two groups of worms or the existence of an antagonistic association between nematodes and cestodes mediated by the immune response of the host. [ABSTRACT FROM AUTHOR]

Abstract: An epidemiological study of helminths in 1040 red foxes collected from various localities in Denmark during 1997–2002, revealed 21 helminth species at autopsy, including nine nematode species: Capillaria plica (prevalence 80.5%), Capillaria aerophila (74.1%), Crenosoma vulpis (17.4%), Angiostrongylus vasorum (48.6% from Northern Zealand (endemic area)), Toxocara canis (59.4%), Toxascaris leonina (0.6%), Uncinaria stenocephala (68.6%), Ancylostoma caninum (0.6%), and Trichuris vulpis (0.5%); seven cestodes: Mesocestoides sp. (35.6%), a number of Taeniid species (Taenia pisiformis, T. hydatigena, T. taeniaeformis, T. crassiceps, and unidentified Taenia spp.) (22.8%), and Echinococcus multilocularis (0.3%); four trematodes: Alaria alata (15.4%), Cryptocotyle lingua (23.8%), Pseudamphystomum truncatum (3.6% from Northern Zealand), and Echinochasmus perfoliatus (2.4% from Northern Zealand); one acanthocephalan: Polymorphus sp. (1.2%). Significant difference in prevalence was found for T. canis and A. vasorum according to host sex, and for T. canis, U. stenocephala, Mesocestoides sp., Taenia spp., A. alata, A. vasorum, and Capillaria spp. according to age groups (adult, young or cub). Prevalence and average worm intensity for each helminth species varied considerably according to geographical locality, season, and year. Aggregated distribution was found for several helminth species. The two species E. multilocularis and E. perfoliatus are first records for Denmark. [Copyright &y& Elsevier]

Microscopy has a long and distinguished history in the study of helminth parasites and has made a singularly outstanding contribution to understanding how these complex animals organise their lives and relate to their hosts. Increasingly, the microscope has been used as a powerful investigative tool in multidisciplinary approaches to parasitological problems, placing emphasis on functional correlates rather than anatomical detail. In doing so, microscopy has also uncovered a number of attributes of parasites that are of wider significance in the field of biology. Parasite surfaces have understandably demanded most of the attention of microscopists, largely as a result of the pioneering studies using transmission electron microscopy. Their findings focused the attention of physiologists and immunologists on the tegument and cuticle of helminths and in doing so helped unravel the complex molecular exchanges that are fundamental to understanding host–parasite interactions. Scanning electron microscopy succeeded in augmenting these data by revealing novel microtopographical features of the host–parasite relationship, as well as proving invaluable in helminth taxonomy and in assessing the efficacy of test substances in drug screens. Control of helminth parasites has never been more critical: problems of drug resistance demand urgent action to identify exploitable targets for new generation anthelmintics. In this regard, the neuropeptide signalling system of helminths is envisioned as central to nerve–muscle function, and thereby a crucial regulatory influence on their motility, alimentation and reproduction. The use of immunocytochemistry interfaced with confocal scanning laser microscopy has not only been instrumental in discovering the peptidergic system of helminths and its potential for chemotherapeutic exploitation, but through increasingly sophisticated bio-imaging technologies has continued to help dissect and analyse the molecular dynamics of this and other cellular systems within these important parasites. [Copyright &y& Elsevier]