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The fast technological advances of molecular tools have enabled us to uncover a new dimension hidden within parasites and their hosts: their microbiomes. Increasingly, parasitologists characterise host microbiome changes in the face of parasitic infections, revealing the potential of these microscopic fast-evolving entities to influence host-parasite interactions. However, most of the changes in host microbiomes seem to depend on the host and parasite species in question. Furthermore, we should understand the relative role of parasitic infections as microbiome modulators when compared with other microbiome-impacting factors (e.g., host size, age, sex). Here, we characterised the microbiome of a single intermediate host species infected by two parasites belonging to different phyla: the acanthocephalan Plagiorhynchus allisonae and a dilepidid cestode, both infecting Transorchestia serrulata amphipods collected simultaneously from the same locality. We used the v4 hypervariable region of the 16S rRNA prokaryotic gene to identify the hemolymph bacterial community of uninfected, acanthocephalan-infected, and cestode-infected amphipods, as well as the bacteria in the amphipods' immediate environment and in the parasites infecting them. Our results show that parasitic infections were more strongly associated with differences in host bacterial community richness than amphipod size, presence of amphipod eggs in female amphipods, and even parasite load. Amphipods infected by acanthocephalans had the most divergent bacterial community, with a marked decrease in alpha diversity compared with cestode-infected and uninfected hosts. In accordance with the species-specific nature of microbiome changes in parasitic infections, we found unique microbial taxa associating with hosts infected by each parasite species, as well as taxa only shared between a parasite species and their infected hosts. However, there were some bacterial taxa detected in all parasitised amphipods (regardless of the parasite species), but not in uninfected amphipods or the environment. We propose that shared bacteria associated with all hosts parasitised by distantly related helminths may be important either in helping host defences or parasites' success, and could thus interact with host-parasite evolution., (Copyright © 2024 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

This study investigated the in vitro antimicrobial and anthelmintic effect of copper nanoparticles (CuNPs) against the bacterium Aeromonas hydrophila, the monogeneans Dactylogyrus minutus, Dactylogyrus extensus, Gyrodactylus cyprini, and the cestode Schyzocotyle acheilognathi, as well as their toxicity to Cyprinus carpio Koi. In the antimicrobial in vitro test, the inhibition zone method and minimum inhibitory concentration (MIC) were performed. In order to determine the time and efficacy of monogenean parasite mortality, the parasites were exposed to CuNP concentrations of 20, 50, 100, 150, 200, and 300 mg L -1 , and a control group with tank water and one with copper sulphate pentahydrate (CuSO 4 . 5 H 2 O) at a concentration of 0.3 mg L -1 , performed in triplicate. The parasites were observed every 10 min for 300 min, and mortality was recorded. For the cestodes, parasites were immersed in CuNP concentrations of 50, 100, 150, and 300 mg L -1 . At the end of the in vitro tests, the anthelmintic efficacy of each treatment was calculated. To assess the tolerance and toxicity in fish, they were exposed to CuNP concentrations of 0.6, 1.25, 2.5, 5, 10, 20, and 50 mg L -1 for 12 h. The MIC demonstrated that CuNPs effectively inhibited the growth of A. hydrophila up to a dilution of 12,500 mg L -1 and showed an inhibition zone of 14.0 ± 1.6 mm for CuNPs. The results of anthelmintic activity showed a dose-dependent effect of concentration for both groups of parasites, with the most effective concentration being 300 mg L -1 in 120 min. In the toxicity test, the carps showed tolerance to lower concentrations. The study indicated that CuNPs were effective against the studied pathogens. However, it proved to be toxic to fish at high concentrations. The use of low concentrations is recommended still requires further investigation., (© 2024 John Wiley & Sons Ltd.)

The NLRP3 receptor can assemble inflammasome platforms to trigger inflammatory responses; however, accumulating evidence suggests that it can also display anti-inflammatory properties. Here, we explored the role of nucleotide-binding oligomerization domain pyrin-containing protein 3 (NLRP3) in Taenia crassiceps experimental infection, which requires immune polarization into a Th2-type profile and peritoneal influx of suppressive macrophages for successful colonization. NLRP3 deficient mice (NLRP3 -/- ) were highly resistant against T. crassiceps, relative to wild-type (WT) mice. Resistance in NLRP3 -/- mice was associated with a diminished IL-4 output, high levels of IL-15, growth factor for both innate and adaptive lymphocytes, and a dramatic decrease in peritoneum-infiltrating suppressive macrophages. Also, a transcriptional analysis on bone marrow-derived macrophages exposed to Taenia-secreted antigens and IL-4 revealed that NLRP3 -/- macrophages express reduced transcripts of relm-α and PD-1 ligands, markers of alternative activation and suppressive ability, respectively. Finally, we found that the resistance displayed by NLRP3 -/- mice is transferred through intestinal microbiota exchange, since WT mice co-housed with NLRP3 -/- mice were significantly more resistant than WT animals preserving their native microbiota. Altogether, these data demonstrate that NLRP3 is a component of innate immunity required for T. crassiceps to establish, most likely contributing to macrophage recruitment, and controlling lymphocyte-stimulating cytokines such as IL-15., Competing Interests: Declarations Conflicts of interest The authors declare no competing interests. Institutional review board statement The study was approved by the FES-Iztacala Bioethics Committee (CE/FESI/042022/1513) and met the recommended guidelines issued by government for experimental animal care (NOM-062-ZOO-1999). Informed consent Not applicable., (© 2024. The Author(s).)

Leopardus geoffroyi (Geoffroy's cat) is a neotropical feline considered globally threatened. In Brazil, it occurs exclusively in the Pampa biome. Its predatory habits contribute to the infection, dispersion, and continuation of the life cycle of various pathogens, including helminths, within ecosystems. However, few studies involving cestodes in wild felines are found in the literature, especially in Brazil. Therefore, we aimed to report the first case of parasitism by Hydatigera taeniaeformis in L. geoffroyi. The helminths were found in the small intestine of the necropsied feline. Specimens were analyzed morphometrically and subjected to molecular analyses for taxonomic identification. The molecular phylogeny based on the analysis of the mitochondrial gene (COX1) allowed the identification of these parasites. Thus, this is the first description of H. taeniaeformis parasitizing L. geoffroyi in Brazil. Consequently, the number of known host species parasitized by this helminth in the country and the world is increased. Additionally, a new molecular sequence is being provided, contributing to the knowledge of Hydatigera in South America., Competing Interests: Declaration of competing interest The authors declare that there is no conflict of interest., (Copyright © 2024. Published by Elsevier B.V.)

Fisheries play a crucial role in aquatic ecosystems, a resource with ecological and economic importance. Measuring parasite prevalence is necessary to assess these fish species' health and well-being. Within the Sistan region, this study sought to estimate the prevalence and intensity of infection with plerocercoid  Ligula intestinalis ( L. intestinalis ) in seven fish species and identify factors such as fish weight, seasonality, and fishing location that might influence infection rates. 2800 fish from seven species were obtained in the Sistan region throughout four seasons. Fish samples from three weight categories (<200gr, 200-400gr, 400gr<) were examined parasitologically. Ligula intestinalis  was detected in 96/2800 (3.4%) of fishs. There was a variation in prevalence among fish species. Alburnus charusini ( A. charusini ), Hypophthalmichthys molitrix ( H. molitrix ) , Hypophthalmichthys nobilis ( H. nobilis ) , and  Schizocypris altidorsalis ( S. altidorsalis ) showed no infection. Schizothorax zarudnyi ( S. zarudnyi ) showed a prevalence of 1.5% (6/400), Cyprinus carpio ( C. carpio ) 15% (60/400), and Ctenopharyngodon idella ( C. idella ) 7.5% (30/400). It was found that infection prevalence was significantly influenced by fish weight in C . carpio  and C . idella . A higher prevalence was found in fish with lower weight. Infection rates significantly fluctuated with season across species, but fishing locations had no significant difference. The present study highlights the significant prevalence of L. intestinalis infections in fish populations within Iran's Sistan region, underscoring the need for ongoing monitoring and research to inform effective fishery management strategies. Future studies should focus on long-term monitoring efforts and consider the broader global context of fish parasitology to understand parasite-host interactions better and inform conservation measures worldwide., Competing Interests: Conflict of interestThe authors declare no conflict of interest., (© Indian Society for Parasitology 2024.)

Parasite infections are increasingly reported to change the microbiome of the parasitized hosts, while parasites bring their own microbes to what can be a multi-dimensional interaction. For instance, a recent hypothesis suggests that the microbial communities harboured by parasites may play a role in the well-documented ability of many parasites to manipulate host phenotype, and explain why the degree to which host phenotype is altered varies among conspecific parasites. Here, we explored whether the microbiomes of both hosts and parasites are associated with variation in host manipulation by parasites. Using colour quantification methods applied to digital images, we investigated colour variation among uninfected Transorchestia serrulata amphipods, as well as amphipods infected with Plagiorhynchus allisonae acanthocephalans and with a dilepidid cestode. We then characterized the bacteriota of amphipod hosts and of their parasites, looking for correlations between host phenotype and the bacterial taxa associated with hosts and parasites. We found large variation in amphipod colours, and weak support for a direct impact of parasites on the colour of their hosts. Conversely, and most interestingly, the parasite's bacteriota was more strongly correlated with colour variation among their amphipod hosts, with potential impact of amphipod-associated bacteria as well. Some bacterial taxa found associated with amphipods and parasites may have the ability to synthesize pigments, and we propose they may interact with colour determination in the amphipods. This study provides correlational support for an association between the parasite's microbiome and the evolution of host manipulation by parasites and host-parasite interactions more generally., (© The Author(s) 2024. Published by Oxford University Press on behalf of the European Society of Evolutionary Biology.)

The general aim of this study is to analyse the risk factors for gastrointestinal parasitosis in small ruminants in order to contribute to the emergence of targeted treatment methods, at herd and agro-climatic zone levels, for the integrated and sustainable management of parasitic diseases in Sahelian livestock systems. The methodology was based on a questionnaire survey conducted in 37 villages and coprological analysis using the McMaster method on faecal samples from 968 small ruminants, including 555 goats and 413 sheep. Multiple logistic regression was used to highlight the risk factors associated with each type of parasitosis encountered. The results showed that the most widespread farming system remained 100% traditional, with feeding based essentially on natural grazing. Coprological results showed the prevalence of nematodosis (70.2%), Cestodosis (4.1%) and Coccidiosis (79.9%), with an average prevalence of coinfection of 56.9%. These parasite loads were significantly higher during the rainy season and in the more arid northern Sahelian zone, with a marked reduction at the end of the season. Average parasitic egg excretions were 1089 EPG of nematodes and 6864 EPG of coccidia. Parasite loads were higher in the wetter southern strip and varied significantly by breed. Of the five breeds of small ruminants studied, the ara-ara sheep had the highest parasitic loads and prevalences for nematodosis (78.6%), coccidiosis (89,3%) and coinfection (70.9%), appears to be the most susceptible to parasitosis. As for risk factors for severe parasite pressure, animals at the end of the rainy season, older animals and those with poor body condition were at risk of nematodiasis or coinfection. On the other hand, animals at the beginning of the rainy season, farms located in less arid southern Sahelian zones and male subjects were the groups at significant risk of coccidiosis. In these extensive Sahelian farming conditions, the control of these parasitoses by selective treatment of animals could be developed, targeting in particular the risk groups highlighted in this study., Competing Interests: Declaration of competing interest The authors declared that they have no competing interests in the publication of this manuscript., (Copyright © 2023. Published by Elsevier B.V.)

A 2-year-old Kunekune sow was submitted for necropsy following death after peritonitis and sepsis. In addition to peritonitis, numerous fluid-filled cysts were identified in the mesentery and hepatic parenchyma, which contained an approximately 1 cm metacestode (cysticercosis). Subsequent molecular characterization confirmed the presence of Taenia hydatigena, a non-zoonotic cestode species. To our knowledge, visceral cysticercosis caused by T. hydatigena has not been previously documented in Kunekune pigs. Taenia solium is a differential diagnosis of public health importance in cases of cysticercosis. Although Taenia solium is not commonly reported nor endemic in the United States, its zoonotic potential warrants consideration in the initial diagnostic assessment. Clinicians should be aware of the presence of T. hydatigena in its definitive and intermediate hosts., (© 2024 G. M. Giallombardo et al., published by Sciendo.)

Bertiella spp. is a mite-borne cestode parasite that inhabits the small intestine of wide range of mammals, including non-human primates. In the present study, the morphological and molecular analysis of Bertiella studeri recovered from the small intestine of a bonnet macaque ( Macaca radiata ) from Wayanad, Kerala (South India) was performed. Acetic alum carmine staining identified the cestode morphologically based on the characters like broader proglottids, which contain irregularly alternating genital pores, single set of reproductive organs, 280 testes and a tubular transverse uterus. Molecular characterization was done using 18SrRNA, ITS1-5.8S and COX1 genes. Phylogenetic trees were constructed using MEGA X based on the Maximum Likelihood (ML) method (Hasegawa-Kishino-Yano (HKY) model). Cytochrome oxidase I gene could detect the existence of genetic variation in the parasite from two different hosts viz., monkey (Kerala, Argentina, and Kenya) and human (Sri Lanka). A minimum spanning network of haplotypes was generated by the haplotype networking with the above sequences using the popARTv1.7. Haplotype analysis based on COX1 revealed that the parasite haplotype was different in each country with highest population frequency in Sri Lanka., (© 2024 P. F. Sebasteena et al., published by Sciendo.)

Introduction: Gastrointestinal helminth parasitism is an important problem of livestock in many places of the globe. Despite the fact that the disease is one of the leading causes of economic losses, there is little information on the occurrence of the infection in cattle and sheep in Ethiopia., Methods: A cross-sectional study was conducted from June 2022 to February 2023 in urban and peri-urban areas of the Ada'a District with the objective of estimating the prevalence of gastrointestinal helminth parasites (GIHPs) in sheep and cattle and to assess the commercial anthelmintic utilization practices and associated risk factors in sheep and cattle. A total of 351 randomly selected fecal samples (192 cattle and 159 sheep) were collected from the rectum and examined using flotation and sedimentation. One hundred respondents were interviewed for questionnaire surveys on anthelmintic utilization practices., Results and Discussion: The overall prevalence of GIHPs (61.25%) was recorded during the study. Among the animals, 55.21% and 68.55% prevalence of the infection was observed in cattle and sheep, respectively. There was a statistically significant difference (P < 0.05) in gastrointestinal helminth parasite (GIHP) infection between the study animal species, breeds, body condition of the animals, and production systems. However, there were no significant differences in gastrointestinal helminth parasite (GIHP) infection (P > 0.05) according to sex and age of the animals. A higher prevalence of strongyle (55.34%), fasciola (13.48%), and moniezia eggs (10.69%) was recorded. According to a questionnaire survey, ivermectin was found to be the most used anthelmintic drug. This study addresses the challenge of anthelmintic resistance (AR) against currently available anthelmintics; highly prevalent parasitic infections are causing tremendous economic losses to the animal industry., Competing Interests: The authors report no conflicts of interest in this work., (© 2024 Alkadir and Ayana.)

White-tailed antsangies (Brachytarsomys albicauda) are Madagascan rodents uncommonly kept in captivity. Hymenolepis nana is a cestode with an unusual life cycle, incorporating direct, indirect and autoinfective stages. This case series represents the first reported outbreak of H. nana cestodiasis in white-tailed antsangies, summarizing macroscopic and histological findings in four cases. On post-mortem examination (PME), numerous cysticerci were detected consistently throughout the intestinal serosa, liver, mesenteric lymphatic vasculature and mesenteric lymph nodes. Pancreatic cysticerci were observed in one case. Adult tapeworms, larvae and eggs were found only in the small intestine, and faecal egg shedding was a feature. Histopathological examination identified adult, larval and encysted cestodes within the respective gross lesions, with pulmonary, pancreatic and splenic involvement detected in a single case. The cestodes sampled on PME were identified by polymerase chain reaction and DNA sequencing, with H. nana confirmed in all cases. Visceral larva migrans was consistent throughout all specimens, in contrast with the natural infections of standard rodent hosts, and may be considered a likely pathological feature of H. nana infection in white-tailed antsangies., Competing Interests: Declaration of competing interests The authors declared no conflicts of interest in relation to the research, authorship or publication of this article., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Background and Aim: Schima wallichii Korth., commonly known as the needlewood tree (family Theaceae) has therapeutic uses in traditional Mizo medicine for human helminthiasis and serves as a balm against ectoparasites in animals. Although the medicinal properties have been studied experimentally, its use as a traditional anthelmintic remains unexplored. This study aimed to analyze the chemical components and antiparasitic activity of S. wallichii ., Materials and Methods: The chemical analysis of S. wallichi bark extracts was conducted focusing on the secondary metabolites using petroleum ether, chloroform, and methanol. Gas chromatography-mass spectrometry (GC-MS) was used to identify the specific compounds. An anthelmintic susceptibility test was carried out against Raillietina tetragona , intestinal cestode parasite of fowl., Results: The methanol extract yielded the highest concentrations of alkaloids, carbohydrates, glycosides, sterols, saponins, and tannins among all the extracts. Sterols were the most abundant compounds in all extracts, with flavonoids being absent. Secondary metabolites were largely absent in the petroleum ether and chloroform extracts. The GC-MS data identified cholest-22-ene-21-ol as the major steroid component. The cestode parasite was inhibited in a concentration-dependent manner by the plant extract. The plant extract's anthelmintic activity was evident through observable damage to the parasite's outer structure., Conclusion: Phytosterols in S. wallichii bark are responsible for its anthelmintic properties. The mechanism and pharmaceutical properties of the anthelmintic molecule require further exploration., Competing Interests: The authors declare that they have no competing interests., (Copyright: © Lalthanpuii and Lalchhandama.)

Taenia solium can cause human taeniasis and/or cysticercosis. The latter can in some instances cause human neurocysticercosis which is considered a priority in disease-control strategies and the prevention of mental health problems. Glutathione transferases are crucial for the establishment and long-term survival of T. solium; therefore, we structurally analyzed the 24-kDa glutathione transferase gene (Ts24gst) of T. solium and biochemically characterized its product. The gene promoter showed potential binding sites for transcription factors and xenobiotic regulatory elements. The gene consists of a transcription start site, four exons split by three introns, and a polyadenylation site. The gene architecture is conserved in cestodes. Recombinant Ts24GST (rTs24GST) was active and dimeric. Anti-rTs24GST serum showed slight cross-reactivity with human sigma-class GST. A 3D model of Ts24GST enabled identification of putative residues involved in interactions of the G-site with GSH and of the H-site with CDNB and prostaglandin D 2 . Furthermore, rTs24GST showed optimal activity at 45 °C and pH 9, as well as high structural stability in a wide range of temperatures and pHs. These results contribute to the better understanding of this parasite and the efforts directed to fight taeniasis/cysticercosis., (© 2024 The Authors. FEBS Open Bio published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.)

Dipylidium caninum is a common tapeworm of dogs. Two cases of praziquantel resistance have been described in D. caninum in the United States. No further reports have been published to the authors’ knowledge. Here, the case of a dog imported to Switzerland from Spain with a history of chronic excretion of tapeworm proglottids and unresponsiveness to praziquantel treatments is reported. Clinical signs were mild (restlessness, tenesmus, anal pruritus, squashy feces) and flea infestation could be ruled out. Infection with D. caninum was confirmed through morphological and genetic parasite identification. Different subsequently applied anthelmintic compounds and protocols, including epsiprantel, did not confer the desired effects. Proglottid shedding only stopped after oral mebendazole administration of 86.2 mg kg −1 body weight for 5 consecutive days. Clinical signs resolved and the dog remained coproscopically negative during a follow-up period of 10 months after the last treatment. This case represents the first reported apparent praziquantel and epsiprantel resistance in D. caninum in Europe. Treatment was extremely challenging especially due to the limited availability of efficacious alternative compounds.

Our knowledge of parasites in wildlife remains limited, primarily due to restricted access to samples, especially of parasites from protected species. This present study contributes to the comprehension of the enigmatic world of helminths of African wild mammals and cestode biodiversity by combining both molecular and morphological analysis. Cestode samples were opportunistically collected from 77 individual definitive hosts in South Africa, Namibia and Ethiopia, encompassing 15 different species of wild African carnivores and additionally domestic cats. The analysis revealed 32 different cyclophyllidean species of which 21 (65.6 %) represent previously unknown genetic entities. They belong to the families Mesocestoididae, Hymenolepididae, Dipylidiidae and Taeniidae. Here we cover the non-taeniid cestodes, while the taeniids will be addressed in a separate publication. Three of the non-taeniid species uncovered in this study could be assigned to the genus Mesocestoides and were isolated from servals and domestic cats. The white-tailed mongoose was found to be a suitable host for a species belonging to the Hymenolepididae, which was identified as Pseudandrya cf. mkuzii . Both feline and canine genotypes of Dipylidium caninum were detected in domestic cats, the canine genotype also in an African wolf. In addition to these, a novel species of Dipylidium was discovered in an aardwolf. Lastly, four distinct species of Joyeuxiella were found in this study, revealing a cryptic species complex and emphasizing the need for a taxonomic reassessment of this genus. Despite the limited scope of our study in terms of geography and sample size, the results highlight that biodiversity of cestodes in African wild mammals is grossly under-researched and follow-up studies are urgently required, in particular linking morphology to gene sequences., Competing Interests: The authors declare no conflict of interest., (© 2024 The Authors. Published by Elsevier Ltd on behalf of Australian Society for Parasitology.)

The emergence of pandemics with dramatic consequences for human health has obscured endemic diseases that continue to pose a problem for human and animal health in several regions of the world. Among these diseases, cystic echinococcosis, a zoonotic parasitic infection caused by a group of cestodes, Echinococcus granulosus sensu lato, remains a real human and animal health problem in several regions of the world, including the Mediterranean Basin. Despite the implementation of a number of governmental control programmes using several tools (dog treatment, meat inspection, etc.), this infection is still highly prevalent in North Africa. Here we present a review of the epidemiology of cystic echinococcosis in Tunisia, an analysis of the constraints limiting the effectiveness of the control programmes implemented, and finally argue for the use of the One Health framework to improve the effectiveness of future programmes., (© M. Gharbi & P. Giraudoux, published by EDP Sciences, 2024.)

Cystic echinococcosis (CE) is a parasitic zoonosis caused by the larval stage of the cestode Echinococcus granulosus sensu lato (s. l.), a genetic complex composed of five species: E. granulosus sensu stricto (s. s.), E. equinus, E. ortleppi, E. canadensis, and E. felidis. The parasite requires two mammalian hosts to complete its life cycle: a definitive host (mainly dogs) harboring the adult parasite in its intestines, and an intermediate host (mostly farm and wild ungulates) where hydatid cysts develop mainly in the liver and lungs. Humans are accidental intermediate hosts, being susceptible to either primary or secondary forms of CE; the first one due to the ingestion of oncospheres, and the second one because of the spillage of protoscoleces (PSC) contained within a primary cyst. Secondary CE is a serious medical problem, and can be modeled in immunocompetent mice (a non-natural intermediate host) through the intraperitoneal inoculation of viable PSC from E. granulosus s. l. This model is useful to study not only the immunobiology of CE, but also to test new chemotherapeutics or therapeutical protocols, to explore novel vaccine candidates, and to evaluate alternative diagnostic and/or follow-up tools. The mouse model of secondary CE involves two sequential stages: an early stage of parasite pre-encystment (PSC develop into hydatid cysts in the peritoneal cavity of mice), and a late or chronic stage of parasite post-encystment (already differentiated cysts slowly grow during the whole host lifespan). This model is a time-consuming infection, whose outcome depends on several factors like the parasite infective dose, the mouse strain, and the parasite species/genotype. Thus, such variables should always be adjusted according to the research objectives. Herein, the general materials and procedures needed to establish secondary CE in mice are described, as well as several useful tips and recommendations., (Copyright © 2024 Elsevier Inc. All rights are reserved, including those for text and data mining, AI training and similar technologies.)

The chicken business faces substantial economic losses due to the risk of parasitic coinfection. Because the current study aimed to investigate enteric parasitic coinfections problems among the suspected examined chicken farms, samples were collected during the field investigation from suspected freshly dead birds, clinically diseased, apparently healthy, and litter samples for further laboratory parasitological, histopathological, and immunological examinations. Variable mortalities with various clinical indicators, such as ruffled feathers, weight loss, diarrhea of various colors, and a decline in egg production, occurred on the farms under investigation. In addition, the treatment protocols of each of the farms that were evaluated were documented and the m-RNA levels of some cytokines and apoptotic genes among the infected poultry have been assessed. The prevalence rate of parasitic coinfection in the current study was found to be 8/120 (6.66%). Parasitological analysis of the samples revealed that they belonged to distinct species of Eimeria, cestodes, and Ascaridia galli. When deposited, A. galli eggs were nonembryonated and ellipsoidal, but cestodes eggs possessed a thin, translucent membrane that was subspherical. Eimeria spp. oocysts in layer chickens were identified as Eimeria acervulina and Eimeria maxima in broiler chickens. Our findings proved that coinfection significantly upregulated the IL-1β, BAX, and Cas-3 genes. Conversely, the IL-10, BCL-2, and AKT mRNA levels were downregulated, indicating that nematode triggered apoptosis. The existence of parasite coinfection was verified by histological investigation of the various intestinal segments obtained from affected flocks. A. galli and cestodes obstructed the intestinal lumen, causing different histological alternations in the intestinal mucosa. Additionally, the lamina propria revealed different developmental stages of Eimeria spp. It was determined that parasite coinfection poses a significant risk to the poultry industry. It was recommended that stringent sanitary measures management methods, together with appropriate treatment and preventative procedures, be employed in order to resolve such issues., (Copyright © 2023 The Authors. Published by Elsevier Inc. All rights reserved.)

The plerocercoid of Spirometra mansoni can parasitize both human and animals, resulting in sparganosis. Lactate dehydrogenase (LDH) is an important enzyme in parasites. However, our knowledge of the LDH family in S. mansoni is still inadequate. This work identified 19 new LDH members in S. mansoni . Clustering analysis demonstrated that all Sm LDHs were divided into two main groups, which is consistent with the patterns of conserved motif organization. According to RT-qPCR, 2 LDHs were highly expressed in the plerocercoid stage and 17 LDHs were highly expressed in the adult stage. The evolutionary tree showed a high level of diversity of both cestode and trematode LDHs. Sm LDHs contained both conserved family members and members in the process of further diversification. r Sm LDH has a NAD-binding domain and a substrate-binding domain. The protein was immunolocalized in the epidermis of the pleroceroid and in the tegument, uterus and egg shell of adult worms. The optimum activity for r Sm LDH in the pyruvate reduction reaction was found to be pH 4.5 and 37 °C. In the oxidation reaction, optimal values for pH and temperature were 9.0 and 30 °C, respectively. Gossypol was found to be the most powerful inhibitor in both reduction and oxidation reactions. The results provide a basis for the further study of the biological roles of LDHs in S. mansoni and other LDH-containing taxa.

Parasites with complex life cycles often manipulate the phenotype of their intermediate hosts to increase the probability of transmission to their definitive hosts. Infection with Anomotaenia brevis, a cestode that uses Temnothorax nylanderi ants as intermediate hosts, leads to a multiple-fold extension of host lifespan and to changes in behaviour, morphology and colouration. The mechanisms behind these changes are unknown, as is whether the increased longevity is achieved through parasite manipulation. Here, we demonstrate that the parasite releases proteins into its host with functions that might explain the observed changes. These parasitic proteins make up a substantial portion of the proteome of the hosts' haemolymph, and thioredoxin peroxidase and superoxide dismutase, two antioxidants, exhibited the highest abundances among them. The largest part of the secreted proteins could not be annotated, indicating they are either novel or severely altered during recent coevolution to function in host manipulation. We also detected shifts in the hosts' proteome with infection, in particular an overabundance of vitellogenin-like A in infected ants, a protein that regulates division of labour in Temnothorax ants, which could explain the observed behavioural changes. Our results thus suggest two different strategies that might be employed by this parasite to manipulate its host: secreting proteins with immediate influence on the host's phenotype and altering the host's translational activity. Our findings highlight the intricate molecular interplay required to influence the phenotype of a host and point to potential signalling pathways and genes involved in parasite-host communication., (© 2023 The Authors. Molecular Ecology published by John Wiley & Sons Ltd.)

Dipylidium caninum infections in dogs and cats are underestimated because of a lack of proglottid observations and poor recovery of parasite elements by centrifugal flotation. We developed an immunoassay that employs a pair of monoclonal antibodies to capture D. caninum- specific coproantigen in fecal extracts from dogs and cats. Real-time PCR for D. caninum DNA in perianal swabs and observation of proglottids were used as reference methods. In 6 experimentally infected dogs, parasite DNA, coproantigen, and proglottid segments were first detected at 22, 23, and 26 d post-infection, respectively. Praziquantel treatment of 3 experimentally infected dogs resulted in the elimination of both coproantigen and proglottid shedding within 1-5 d post-treatment; however, parasite DNA persisted for 14 d. Immunohistochemistry on immature and mature tapeworm segments using an antibody against the coproantigen supports the premise that the antigen is produced in mature segments. We assessed the performance of our coproantigen test in natural infections in 78 dogs from a flea-endemic area. Of the 12 antigen-positive samples, 11 were confirmed with a positive PCR test and/or proglottid observation. Finally, we evaluated a convenience sample set of 730 canine and 163 feline fecal samples obtained from a commercial diagnostic laboratory; D. caninum antigen was detected in 4.1% of the canine and 12.9% of the feline samples, whereas parasite elements were observed in only 0.028% of samples. Our coproantigen immunoassay provides a sensitive method for the detection of D. caninum infection in dogs and cats., Competing Interests: Declaration of conflicting interestsAll authors are employees of Idexx Laboratories.

Background: Tapeworm larvae cause important diseases in humans and domestic animals. During infection, the first larval stage undergoes a metamorphosis where tissues are formed de novo from a population of stem cells called germinative cells. This process is difficult to study for human pathogens, as these larvae are infectious and difficult to obtain in the laboratory., Methods: In this work, we analyzed cell proliferation and differentiation during larval metamorphosis in the model tapeworm Hymenolepis microstoma , by in vivo labelling of proliferating cells with the thymidine analogue 5-ethynyl-2'-deoxyuridine (EdU), tracing their differentiation with a suite of specific molecular markers for different cell types., Results: Proliferating cells are very abundant and fast-cycling during early metamorphosis: the total number of cells duplicates every ten hours, and the length of G2 is only 75 minutes. New tegumental, muscle and nerve cells differentiate from this pool of proliferating germinative cells, and these processes are very fast, as differentiation markers for neurons and muscle cells appear within 24 hours after exiting the cell cycle, and fusion of new cells to the tegumental syncytium can be detected after only 4 hours. Tegumental and muscle cells appear from early stages of metamorphosis (24 to 48 hours post-infection); in contrast, most markers for differentiating neurons appear later, and the detection of synapsin and neuropeptides correlates with scolex retraction. Finally, we identified populations of proliferating cells that express conserved genes associated with neuronal progenitors and precursors, suggesting the existence of tissue-specific lineages among germinative cells., Discussion: These results provide for the first time a comprehensive view of the development of new tissues during tapeworm larval metamorphosis, providing a framework for similar studies in human and veterinary pathogens., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Montagne, Preza and Koziol.)

A taxonomic review was performed on cestodes of the genus Neoskrjabinolepis Spassky, 1947 that parasitize different species of Sorex shrews in different regions of the northern Palearctic and in the Nearctic (Alaska, USA). Information on Palearctic Neoskrjabinolepis cestodes published in various articles is summarized. An overview of the geographical distribution of the Neoskrjabinolepis species is also presented. Currently, the genus includes 17 species. In the European part of the Palearctic, four species of the genus are registered; in the Asian part, 13 species; and on the American continent (Seward Peninsula, Alaska, USA), two species. Descriptions, illustrations, and differential diagnoses are given for a new species of Neoskrjabinolepis , i.e. N. paradoxa n. sp., which was found in shrews Sorex unguiculatus Dobson and S. caecutiens Laxmann on Sakhalin Island. A unique feature of the new species is irregularly alternating genital pores in the uterus series in the strobila. Amended new differential features (positioning of the uterus relative to osmoregulatory canals and alternation of genital pores) of genus diagnosis and an identification key for Neoskrjabinolepis spp. are presented.

Parasitism of cephalopods is common, including infection with Aggregata spp., Ichthyobodo spp ., dicyemids, cestodes of the orders Tetraphyllidea and Trypanorhynchidea, and various crustaceans. Cestodiasis in octopuses is reported, although a full histologic description of lesions has not been previously described. Cestodiasis was identified in 10 octopuses of 4 different species, which included 4 common octopuses ( Octopus vulgaris ), 3 Caribbean reef octopuses ( Octopus briareus ), 2 two-spot octopuses ( Octopus bimaculoides ), and 1 giant Pacific octopus ( Enteroctopus dofleini ). Larval cestodes were present in the cecum ( n = 5), intestines ( n = 4), digestive gland ( n = 3), chitinous alimentary tract ( n = 2), renal appendage ( n = 1), and salivary duct ( n = 1). In 5 cases, larval cestodes invaded tissue and were associated with hemocytic inflammation and tracts of necrotic tissue in the intestines ( n = 3), digestive gland ( n = 3), and/or renal appendage ( n = 1). When present in the chitinous alimentary tract (esophagus, stomach) or cecum, larval cestodes were in the central lumen and not associated with lesions. One adult cestode was identified in the mantle cavity and was not associated with lesions. Other common concurrent parasitic infections included enteric Aggregata spp . infection, branchial Rickettsia-like organism infection, enteric nematodiasis, and an arthropod-associated branchitis.

Parasites with complex life cycles are known to induce phenotypic changes in their intermediate hosts to increase transmission to the final host. The magnitude of these changes could increase with the number of parasites, which would be beneficial to co-infecting parasites. Yet, adverse effects of high parasite load (i.e. many parasites in a single host) might stress both hosts and parasites (e.g. through an increased immune response). We investigated the consequences of parasite load on the transcriptional activity and morphology of the cestode Anomotaenia brevis and its intermediate host, the ant Temnothorax nylanderi. We demonstrated that many differentially expressed host genes shifted with parasite load, and their functions indicate a stronger immune response and fight against oxidative stress in heavily infected hosts. The expression of other host genes responded to infection in an all-or-nothing manner, as did the morphology of the host workers. However, the cestodes became smaller when they competed with other parasites for resources from a single host. Their expression profile further indicated shifts in host immune avoidance, starvation resistance and vesicle-mediated transport. In summary, our study reveals clear consequences of parasite load and highlights specific processes and traits affected by this., (© 2023 The Authors. Molecular Ecology published by John Wiley & Sons Ltd.)

The tapeworms of Moniezia spp. are heteroxenous parasites and their adult forms occur in ruminants' alimentary tract. They steal a significant portion of hosts' nourishment initiating monieziasis, thereby inflicting economic losses in animal rearing. Despite their high economic importance, the molecular characterization and taxonomic status of these parasites have remained poorly understood. In the present study, cestodes were isolated from the sheep and goats' intestines and were stained with Gower's carmine. Upon careful evaluation of morphological characters, 2 species Moniezia denticulata and Moniezia expansa were identified. The genomic DNA was extracted and polymerase chain reaction (PCR) amplified targeting regions of mitochondrial cytochrome c oxidase subunit 1 ( cox1 ), small subunit ribosomal RNA (SSU rRNA) and internal transcribed spacer 1–5.8S rRNA (ITS1–5.8S rRNA) genes followed by sequencing. The partial sequences of cox1 , SSU rRNA and ITS1–5.8S rRNA genes of M. denticulata generated in the present study revealed that even though they share high similarities with M. benedeni (93.2% cox1 ; 92.6% SSU rRNA; 84.70% ITS1–5.8S rRNA) and M. expansa (88.85% cox1 ; 92.27% SSU rRNA; 81.70% ITS1–5.8S rRNA), they are not identical to them. In the maximum likelihood phylogenetic trees, M. denticulata and M. expansa consistently appeared as distinct species from each other. The high values of pairwise divergence between these 2 species collected in the present study confirmed their separate identity. The present study reports the first molecular characterization of M. denticulata with reference to M. expansa infecting sheep and goats in India.

Morphological characteristics and DNA sequencing were used to identify plerocercoids of a Schistocephalus sp. infecting slimy sculpin (Cottus cognatus) from northern New Brunswick and plerocercoids of Ligula intestinalis infecting blacknose dace (Rhinichthys atratulus) in Fundy National Park (FNP, New Brunswick). To our knowledge, no previous publications documented either cestode from New Brunswick, Canada. Blacknose dace represent a new host record for L. intestinalis. Identifications were made based on the presence or absence of segmentation and sequencing partial nicotinamide adenine dinucleotide dehydrogenase subunit 1 (ND1; mitochondrial DNA) and/or partial cytochrome c oxidase subunit 1 (COI; mitochondrial DNA). Plerocercoids from blacknose dace in FNP were identified as Ligula intestinalis based on >99% nucleotide identity with COI for this species in the NCBI GenBank database. Plerocercoids in slimy sculpin from northern New Brunswick were identified as a Schistocephalus sp. based on high nucleotide identity with congenerics in the NCBI GenBank database. The absence of GenBank entries with sufficient high percent identity to our specimens, and potential species hybrids in this genus, prevents species-level identification of Schistocephalus sp. plerocercoids currently. The absence of previous documentation of these cestodes might reflect recent environmental change promoting the transmission of these parasites that can modulate host fish behavior, induce sterility of host fishes, and contribute to epizootics., (© American Society of Parasitologists 2023.)

Purpose: Tapeworms of Avitellina spp. are among those gastrointestinal parasitic helminths which infect wild and domestic ruminants worldwide leading to various clinical manifestations in the ruminant hosts, thereby causing considerable economic losses in livestock production. While these worms are among the major constraints in ruminant livestock raising, there is very meagre molecular information available making their identity error-prone. This study aimed to provide insights into the genetic characterization of these economically important tapeworms., Methods: In the present study, we examined 480 guts of slaughtered goats (n = 413) and sheep (n = 67) of which 74 guts were found infected with anoplocephalid cestodes (sheep gut:18; goat gut:56). A total of 27 Avitellina lahorea worms (19 from goat and 8 from sheep) were isolated, fixed, relaxed and stained using Gower's carmine stain. For molecular analyses, the genomic DNA was extracted and fragments of cytochrome c oxidase subunit 1 (cox1) gene, internal transcribed spacer1-5.8S ribosomal RNA (ITS1-5.8S rRNA) gene, and small subunit ribosomal RNA (18S rRNA) gene were amplified and sequenced., Results: Based on snail-shaped paruterine organs and other morphological and morphometric features, the worms were identified as Avitellina lahorea. The phylogenetic analyses, based on our original cox1 gene sequence and those available from NCBI GenBank, showed Avitellina tapeworms as a sister lineage of Thysaniezia with 14 to 17% genetic divergence. Molecular analyses of 18S rRNA gene sequences depicted the present isolate as one of the species of the genus Avitellina clustering with A. centripunctata as a separate species in the phylogenetic tree with 92% homogeneity in sequences. In conjunction with existing data of internal transcribed spacer1-5.8S rRNA (ITS1-5.8S rRNA) gene, the phylogenetic analysis placed the present isolate among the anoplocephalids as one of the species., Conclusion: The present study is the first molecular report on A. lahorea isolated from sheep and goats with the simultaneous use of a morphological approach, and certainly contributes to bridging the existing gaps in the understanding of these economically important parasites., (© 2023. The Author(s) under exclusive licence to Witold Stefański Institute of Parasitology, Polish Academy of Sciences.)

Dipylidium caninum (Linnaeus, 1758) is a common zoonotic cestode of dogs and cats worldwide. Previous studies have demonstrated the existence of largely host-associated canine and feline genotypes based on infection studies, differences at the 28S rDNA gene, and complete mitochondrial genomes. There have been no comparative genome-wide studies. Here, we sequenced the genomes of a dog and cat isolate of Dipylidium caninum from the United States using the Illumina platform at mean coverage depths of 45× and 26× and conducted comparative analyses with the reference draft genome. Complete mitochondrial genomes were used to confirm the genotypes of the isolates. Genomes of D. caninum canine and feline genotypes generated in this study, had an average identity of 98% and 89%, respectively, when compared to the reference genome. SNPs were 20 times higher in the feline isolate. Comparison and species delimitation using universally conserved orthologs and protein-coding mitochondrial genes revealed that the canine and feline isolates are different species. Data from this study build a base for future integrative taxonomy. Further genomic studies from geographically diverse populations are necessary to understand implications for taxonomy, epidemiology, veterinary clinical medicine, and anthelmintic resistance.

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.)

Attempts to control cystic echinococcosis (CE) caused by Echinococcus granulosus in the Falkland Islands have been ongoing for over 50 years. No human cases have been recorded since the 1980s but there is a need to establish if the parasite has been completely eliminated from domestic animals. A study was carried out in 2018/2019 to identify dogs infected with E. granulosus using copro-antigen and copro-polymerase chain reaction (PCR) analysis. In addition, annual slaughter data were analysed to establish infection levels of E. granulosus and 2 other taeniid parasites. Results showed that 4 out of 589 dogs (0.7%) tested positive by copro-antigen analysis. Results from similar surveys carried out in 2010, 2012 and 2014 showed 17 (3%), 0 and 6 (1%) copro-antigen-positive dogs, respectively, with 8 dogs being confirmed by PCR in 2010. Annual abattoir data showed that from 2006 to 2020, 36 sheep were identified with E. granulosus (mean 0.0055%), 14 186 sheep with Taenia hydatigena (mean 2.2%) and 465 with Taenia ovis (mean 0.072%). Prevalences of T. hydatigena and T. ovis showed spontaneous rises in certain years where the infections could also be detected in lambs indicating that viable taeniid eggs were present. Observations of farm management procedures indicated that there were occasions when dogs could get access to infective taeniid material. In conclusion, E. granulosus is still present in sheep and dogs but at low prevalences. The increasing presence of T. hydatigena however, indicates that control measures are defective in some areas and there is potential for a re-emergence of CE.

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: In China, the plerocercoid of the cestode Spirometra mansoni is the main causative agent of human and animal sparganosis. However, the population genetic structure of this parasite remains unclear. In this study, we genotyped S. mansoni isolates with the aim to improve current knowledge on the evolution and population diversity of this cestode., Methods: We first screened 34 perfect simple sequence repeats (SSRs) using all available omic data and then constructed target sequencing technology (Target SSR-seq) based on the Illumina NovaSeq platform. Next, a series of STRUCTURE. clustering, principal component, analysis of molecular variance and TreeMix analyses were performed on 362 worm samples isolated from 12 different hosts in 16 geographical populations of China to identify the genetic structure., Results: A total of 170 alleles were detected. The whole population could be organized and was found to be derived from the admixture of two ancestral clusters. TreeMix analysis hinted that possible gene flow occurred from Guizhou (GZ) to Sichuan (SC), SC to Jaingxi (JX), SC to Hubei (HB), GZ to Yunnan (YN) and GZ to Jiangsu (JS). Both neighbor-joining clustering and principal coordinate analysis showed that isolates from intermediate hosts tend to cluster together, while parasites from definitive hosts revealed greater genetic differences. Generally, a S. mansoni population was observed to harbor high genetic diversity, moderate genetic differentiation and a little genetic exchange among geographical populations., Conclusions: A Target SSR-seq genotyping method was successfully developed, and an in-depth view of genetic diversity and genetic relationship will have important implications for the prevention and control of sparganosis., (© 2022. The Author(s).)

Neurocysticercosis (NCC) is the most prevalent parasitic infection of the central nervous system. It is caused by the presence of larvae of the cestode Taenia solium in the brain. The most common symptom of NCC is seizures, and it is widely considered the world's leading cause of preventable epilepsy. Despite the prevalence and impact of NCC, a thorough, mechanistic understanding of seizure generation is still lacking. In this review, we address the question "What causes seizures in NCC?" by summarizing and discussing the major theories that seek to explain the seizurogenic and epileptogenic processes in this disorder. In addition, we highlight the potential for recent advances in disease modeling to help accelerate progress in this area., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2022.)

Blue sharks, Prionace glauca , are cosmopolitan, extremely vagile sharks and the species among elasmobranchs for which most surveys containing tapeworm community data are available worldwide. In this study we report on the tapeworm fauna of three samples of blue sharks ( n = 37) from two new regions (one sample from Galicia, north-east Atlantic, and two from Valencia, western Mediterranean), and compared it with previous studies, assessing the relative role of the ecological and evolutionary factors in structuring local tapeworm assemblages. Nine cestode taxa were identified, of which four included adult specimens, that is, Platybothrium auriculatum , Prosobothrium armigerum , Anthobothrium caseyi and Molicola horridus . The abundance of these species, and Brillouin's diversity index, differed significantly among samples without a clear geographical signal. A comparison with six previous surveys revealed that tapeworm assemblages were composed of the same 'core' taxa, with mean species richness typically ranging from two to four species. Global records of adult tapeworms in blue sharks included: 15 taxa identified at species level, of which only eight (generalist trypanorhynchs) were shared with other sympatric host species; five mostly with other carcharhinids; and three with large lamnid sharks sharing the blue sharks' habitat. The composition of tapeworm communities of blue sharks is thus highly constrained by strong host specificity, with composition and abundance varying across localities depending on idiosyncratic environmental conditions.

Anoplocephala perfoliata is a common tapeworm in horses causing colic and even mortalities. Current diagnostic tests to detect A. perfoliata infections have their limitations and an improved method is needed. Immunoreactive excretory/secretory proteins (E/S proteome) of this parasite can provide promising candidates for diagnostic tests. We compared E/S proteins produced by small (length < 20 mm, width < 5 mm) and large (length 20 to 40 mm, width 5 to 10 mm) A. perfoliata worms in vitro by label-free quantitative proteomics using a database composed of related Hymenolepis diminuta, Echinococcus multilocularis/granulosus and Taenia aseatica proteins for protein identifications. Altogether, 509 E/S proteins were identified after incubating the worms in vitro for three and eight hours. The greatest E/S proteome changes suggested both worm size- and time-dependent changes in cytoskeleton remodeling, apoptosis, and production of antigens/immunogens. The E/S proteins collected at the three-hour time point represented the natural conditions better than those collected at the eight-hour time point, and thereby contained the most relevant diagnostic targets. Immunoblotting using antibodies from horses tested positive/negative for A. perfoliata indicated strongest antigenicity/immunogenicity with 13-, 30- and 100-kDa proteins, involving a thioredoxin, heat-shock chaperone 90 (Hsp90), dynein light chain component (DYNLL), tubulin-specific chaperone A (TBCA) and signaling pathway modulators (14-3-3 and Sj-Ts4). This is among the first studies identifying new diagnostic targets and A. perfoliata antigens eliciting a IgG-response in horses., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Hautala, Pursiainen, Näreaho, Nyman, Varmanen, Sukura, Nielsen and Savijoki.)

The Spirometra mansoni is a neglect medical tapeworm, its plerocercoid larvae can parasitize in humans and animals, causing sparganosis. In this study, 17 new members of the glutathione transferase (GST) family were sequenced and characterized in S. mansoni . Clustering analysis displayed the categorization of SmGSTs into two main clades. RT-qPCR illustrated that 7 GST genes were highly expressed in the plerocercoid stage while 8 GSTs were highly expressed in the adult. rSmGST has the typical C- and N-terminal double domains of glutathione transferase. Immunolocalization revealed that natural SmGST is mainly located in the epidermis and parenchyma of plerocercoid, and in the epidermis, parenchyma, uterus and egg shell of adult worm. The optimum activity for rSmGST was found to be pH 6.5 and 25°C. The evolutionary tree showed a high level of diversity of cestodes GSTs. SmGSTs contained both conserved family members and members in the process of further diversification. The findings in this study will lay a foundation to better explore the underlying mechanisms of GSTs involved in Spirometra tapeworms., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Chen, Liu, Cheng, Cui, Wang and Zhang.)

Mesocestoides vogae is a cestode of the order Cyclophyllidea, and its second intermediate hosts are mammals, birds, amphibians, and reptiles. The parasite forms a tetrathyridium in the second intermediate host and multiplies asexually, sometimes to the point of filling the host's abdominal cavity. Proliferated tetrathyridium may cause lethal conditions in the host. During the asexual multiplication period, the scolex first replicates into two and then divides into two worms. In this study, to investigate the factors that promote the replication, tetrathyridia were cultured under various in vitro conditions. When several worms which already had two scolexes were cultured together, the division into two worm bodies was complete, but when single worm was cultured, the division hardly proceeded. The result indicates that the division progression of tetrathyridia with two scolexes requires the presence of other worms. In contrast, tetrathyridia with only one scolex did not initiate the division process, whether cultured together or alone. Then, the necessity of direct contact between the bodies of the worms to promote the division of tetrathyridia with two scolexes was assessed. For this, the well of the culture plate was partitioned into upper and lower parts using a mesh, and 20 worms in the upper part and single worm in the lower part were cultured. In all examined wells, worms in the upper part showed complete division, whereas the worms in the lower part rarely completed the division. Thus, direct contact between tetrathyridium promotes the division of tetrathyridia bearing two scolexes., (Copyright © 2022 Elsevier B.V. All rights reserved.)

A new species of Eniochobothrium Shipley and Hornell, 1906 was recovered from the Oman cownose ray ( Rhinoptera jayakari Boulenger) from the body of water off the south-eastern coastline of the KwaZulu-Natal Province, South Africa. Eniochobothrium acostae n. sp. is described on morphological and molecular grounds. The new species is placed within Eniochobothrium (viz., Eniochobothrium gracile Shipley and Hornell, 1906, Eniochobothrium qatarense Al Kawari, Saoud and Wanas, 1994, Eniochobothrium euaxos Jensen, 2005) by possessing key generic characteristics such as the absence of a vagina, expansion of the anterior region of the strobila forming a trough and presence of a thick-walled cirrus sac. Molecular phylogenetic analyses of the partial 28S rRNA and mtCOI genes confirm the generic characterisation as the newly proposed species groups together with other members of the genus. Eniochobothrium acostae n. sp. currently represents the largest described species of the genus; it possesses slightly fewer testes compared to most congeners, given that this feature has been provided in the original description (e.g., E. euaxos and E. qatarense ). The new species of Eniochobothrium is the fourth valid species described to date and the first species record from South African waters., (© 2022 The Authors. Published by Elsevier Ltd on behalf of Australian Society for Parasitology.)

As climate change progresses, thermal stress is expected to alter the way that host organisms respond to infections by pathogens and parasites, with consequences for the fitness and therefore population processes of both host and parasite. The authors used a correlational natural experiment to examine how temperature differences shape the impact of the cestode parasite Schistocephalus solidus on its host, the three-spined stickleback (Gasterosteus aculeatus). Previous laboratory work has found that high temperatures benefit S. solidus while being detrimental to the stickleback. The present study sought to emulate this design in the wild, repeatedly sampling naturally infected and uninfected fish at matched warmer and cooler locations in the Baltic Sea. In this wild study, the authors found little evidence that temperature was associated with the host-parasite interaction. Although infection reduced host condition and reproductive status overall, these effects did not vary with temperature. Host fitness indicators correlated to some extent with temperature, with cooler capture sites associated with larger size but warmer sites with improved reproductive potential. Parasite fitness (prevalence or size) was not correlated with temperature at the capture site. These mismatches between laboratory and field outcomes illustrate how findings from well-controlled laboratory experiments may not fully reflect processes in more variable natural settings. Nonetheless, the findings of this study indicate that temperature can influence host fitness regardless of infection, with potential consequences for both host demography and parasite transmission dynamics in this complex system., (© 2022 The Authors. Journal of Fish Biology published by John Wiley & Sons Ltd on behalf of Fisheries Society of the British Isles.)

The cestode Schistocephalus solidus is a common parasite in freshwater threespine stickleback populations, imposing strong fitness costs on their hosts. Given this, it is surprising how little is known about the timing and development of infections in natural stickleback populations. Previous work showed that young-of-year stickleback can get infected shortly after hatching. We extended this observation by comparing infection prevalence of young-of-year stickleback from 3 Alaskan populations (Walby, Cornelius and Wolf lakes) over 2 successive cohorts (2018/19 and 2019/20). We observed strong variation between sampling years (2018 vs 2019 vs 2020), stickleback age groups (young-of-year vs 1-year-old) and sampling populations.

In this investigation, the incidence and intensity of gastrointestinal parasites of domestic pigeons were evaluated, additionally, in vitro and in vivo evaluation of the antiparasitic activity of chitosan nanoparticles against the most predominant gut parasite. Therefore, 240 domestic pigeons (160 adults and 80 squabs) obtained from different localities in Giza governorate, Egypt, from February to July 2021, were subjected to parasitological and postmortem examination. The results revealed that 97% of pigeons were vulnerable to single or mixed gastrointestinal parasites. The detected helminths were identified as Capillaria columbae (C. columbae) with a total incidence of (12.5%), Ascaridia columbae (A. columbae) (83.3.%), Heterakis gallinarum (H. gallinarum) (18.7%), Raillietina cesticillus (R. cesticillus) (7.5%), Raillietina echinobothrida (R. echinobothrida) (29%), Choanotaenia infundibulum (C. infundibulum) (22.9%), Davainea proglottina (D. proglottina) (26.6%), and Cotugnia proglottina (C. proglottina) (14.5%). At the same time, the identified protozoan parasites were Trichomonas gallinae (T. gallinae), and Eimeria columbae (E. columbae), with a total incidence of 25 and 79%, respectively. Helminths and Eimeria infections were higher in adults than squabs, while T. gallinae infection was reported with a higher incidence in squabs (62.5%) than adults (6.2%). From our findings, A. columbae was the most predominant gut parasite in the examined pigeons. Thus, it was subjected to in vitro and in vivo treatment with chitosan nanoparticles. Serum and tissue samples were collected from the birds which have been used in the in vitro study to evaluate the oxidative stress markers as malondialdehyde (MDA), Nitric oxide levels and Tumor Necrosis Factor-alpha (TNF-α) and Interleukin-1β activity also, chitosan nanoparticles- treated worm ultrastructure were determined using scanning electron microscopy (SEM). Finally, we recommend periodic monitoring of pigeon's farm to detect the parasitic infestation, and from our results, we recommend chitosan nanoparticles as a potent nematocidal agent., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)

Taxonomic evaluations are needed to accurately determine the host selection of fish parasites. The present study is a multidisciplinary research in the field of basic and fish diseases sciences. The description of the hybrid species of Squalius orientalis and Alburnus derjugini and infection of Ligula intestinalis in these hybrid fish were reported for the first time from the Kürtün Dam Lake in northeast Turkey. A total of 450 fish were sampled in March, August, and October in 2020 using gillnets. Detailed morphological characteristics (n = 24) were compared to determine the difference among ancestors and hybrid species. The prevalence of L. intestinalis between the sampling periods and the size groups of fish (0 - 10, 11 - 15, and ≥16 cm in length) were examined. Moreover, the highest prevalence of the parasite was observed in October (78.94 %), with a size range of 0 - 10 cm in length (77.8 %). In addition, the total prevalence of the parasite was 48.44 %. The results revealed that most of the diagnostic metric and meristic features of hybrid fish were ranging between the data of S. orientalis and A. derjugini . According to previous reports, when hybrid individuals were compared with their ancestors in terms of prevalence, hybrid individuals were more susceptible to L. intestinalis infections. This study was unique as it provided the first record of L. intestinalis in a hybrid fish population., Competing Interests: Conflicts of Interest The authors declare that we have no conflict interests., (© 2022 Z. Z. İpek, C. Kaya, Ş. Kayiş, published by Sciendo.)

The first cestode genomes were obtained by an international consortium led by the Wellcome Sanger Institute that included representative institutions from countries where the sequenced parasites have been studied for decades, in part because they are etiological agents of endemic diseases (Argentina, Uruguay, Mexico, Canada, UK, Germany, Switzerland, Ireland, USA, Japan, and China). After this, several complete genomes were obtained reaching 16 species to date. Cestode genomes have smaller relative size compared to other animals including free-living flatworms. Moreover, the features genome size and repeat content seem to differ in the two analyzed orders. Cyclophyllidean species have smaller genomes and with fewer repetitive content than Diphyllobothriidean species. On average, cestode genomes have 13,753 genes with 6 exons per gene and 41% GC content. More than 5,000 shared cestode proteins were accurately annotated by the integration of gene predictions and transcriptome evidence being more than 40% of these proteins of unknown function. Several gene losses and reduction of gene families were found and could be related to the extreme parasitic lifestyle of these species. The application of cutting-edge sequencing technology allowed the characterization of the terminal sequences of chromosomes that possess unique characteristics. Here, we review the current status of knowledge of complete cestode genomes and place it within a comparative genomics perspective. Multidisciplinary work together with the implementation of new technologies will provide valuable information that can certainly improve our chances to finally eradicate or at least control diseases caused by cestodes., (© 2021. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

A growing literature demonstrates the impact of helminths on their host gut microbiome. We investigated whether the stickleback host microbiome depends on ecoevolutionary variables by testing the impact of exposure to the cestode parasite Schistocephalus solidus with respect to infection success, host genotype, parasite genotype, and parasite microbiome composition. We observed constitutive differences in the microbiome of sticklebacks of different origin, and those differences increased when sticklebacks exposed to the parasite resisted infection. In contrast, the microbiome of successfully infected sticklebacks varied with parasite genotype. More specifically, we revealed that the association between microbiome and immune gene expression increased in infected individuals and varied with parasite genotype. In addition, we showed that S. solidus hosts a complex endomicrobiome and that bacterial abundance in the parasite correlates with expression of host immune genes. Within this comprehensive analysis we demonstrated that (i) parasites contribute to modulating the host microbiome through both successful and unsuccessful infection, (ii) when infection is successful, the host microbiome varies with parasite genotype due to genotype-dependent variation in parasite immunomodulation, and (iii) the parasite-associated microbiome is distinct from its host and impacts the host immune response to infection., (© 2022 John Wiley & Sons Ltd.)

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., (© 2021 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.)