An insulin-like signalling pathway model for Fasciola gigantica.

BACKGROUND: The insulin/insulin-like signalling (IIS) pathway is common in mammals and invertebrates, and the IIS pathway is unknown in Fasciola gigantica. In the present study, the IIS pathway was reconstructed in F. gigantica. We defined the components involved in the IIS pathway and investigated the transcription profiles of these genes for all developmental stages of F. gigantica. In addition, the presence of these components in excretory and secretory products (ESPs) was predicted via signal peptide annotation. RESULTS: The core components of the IIS pathway were detected in F. gigantica. Among these proteins, one ligand (FgILP) and one insulin-like molecule binding protein (FgIGFBP) were analysed. Interestingly, three receptors (FgIR-1/FgIR-2/FgIR-3) were detected, and a novel receptor, FgIR-3, was screened, suggesting novel functions. Fg14-3-3ζ, Fgirs, and Fgpp2a exhibited increased transcription in 42-day-old juveniles and 70-day-old juveniles, while Fgilp, Fgigfb, Fgsgk-1, Fgakt-1, Fgir-3, Fgpten, and Fgaap-1 exhibited increased transcription in metacercariae. FgILP, FgIGFBP, FgIR-2, FgIR-3, and two transcription factors (FgHSF-1 and FgSKN-1) were predicted to be present in FgESPs, indicating their exogenous roles. CONCLUSIONS: This study helps to elucidate the signal transduction pathway of IIS in F. gigantica, which will aid in understanding the interaction between flukes and hosts, as well as in understanding fluke developmental regulation, and will also lay a foundation for further characterisation of the IIS pathways of trematodes.

Trematode infection in ruminants and diversity of snail hosts across three agro-ecological zones in Ethiopia.

The occurrence of trematodes among ruminants and their snail vectors is a major concern across various agro-ecological regions of Ethiopia. Trematodes pose significant threats to animals, causing considerable economic losses and impacting public health. In this study, we have investigated 784 ruminant fecal samples, and 520 abattoir samples, alongside the collection and identification of snail vectors from various agro-ecological regions. Fecal examinations revealed Fasciola, Paramphistomum and Schistosoma species infected 20.5% (95% CI: 17.6, 23.8), 11.7% (95% CI: 9.6, 14.2), and 6.3% (95% CI: 4.1, 9.1) of the animals, respectively. The overall prevalence of trematodes among ruminants was 28.8% (95% CI: 25.7, 32.1%), with 6.0% (95% CI: 4.3, 7.7) showing mixed infections. Fasciola was more prevalent in Asela (26%) compared to Batu (19%) and Hawassa (11.5%), while a higher proportion of animals in Batu were infected with Paramphistomum. Schistosoma eggs were detected only in Batu (12.5%), but not in other areas. Sheep and cattle exhibited higher infection rates with Fasciola, Paramphistoma, and Schistosoma compared to goats. Significant associations were observed between trematode infections and risk factors including agro-ecology, animal species, body condition score, and deworming practices. About 20.8% and 22.7% of the slaughtered animals harbored Fasciola and Paramphistomum flukes, respectively, with a higher prevalence in Asela and Hawassa abattoirs compared to Batu abattoir. Additionally, a total of 278 snails were collected from the study areas and identified as lymnae natalensis, lymnae trancatula, Biomphalaria pffiferi, Biomphlaria sudanica, and Bulinus globosus. In conclusion, the study highlights the widespread occurrence of trematode infections, emphasizing the need for feasible control measures to mitigate their economic and public health impacts.

Immune modulation of goat monocytes by Fasciola gigantica Legumain-1 protein (Fg-LGMN-1).

Legumains belonging to C_13 peptidase family of proteins, and are ubiquitously disseminated among all vertebrate and invertebrate organisms, and have been implicated in innumerable biological and cellular functionality. Herein, we characterized and evaluated immunoregulatory characteristics of Legumain-1 from Fasciola gigantica (Fg-LGMN-1) during its interaction with host immune cells. The isopropyl-ß-d-thiogalactopyranoside (IPTG) stimulated RFg-LGMN-1 protein was positively detected by rat serum containing anti-RFg-LGMN-1 polyclonal antibodies. Furthermore, the uptake of RFg-LGMN-1 by goat monocytes was successfully confirmed using Immunofluorescence Assay (IFA). The immunohistochemical analysis revealed the native localization of LGMN-1 protein on the periphery and internal structures such as suckers, pharynx, and genital pore of the adult parasite, thereby validating its presence in excretory-secretory (ES) products of F. gigantica. The RFg-LGMN-1 co-incubated with concanavalin-A (Con-A) stimulated the increase of interleukin 2 (IL-2), IL-10, and IL-17 in monocytes derived from peripheral blood mononuclear cells (PBMCs) in the concentration-dependent manner. However, the IL-4 cytokine in response to the RFg-LGMN-1 protein declined. These results illuminated the role of LGMN-1 during the parasite-host interface. Our findings elaborated additional evidence that Legumain protein play a role in the manipulating host immune responses during parasite infections. However, further evaluation of RFg-LGMN-1 protein in context of its immunomodulatory roles should be conducted to enhance our understandings of the mechanisms employed by F. gigantica to evade host immune responses.

Intra- and interspecies variation and population dynamics of Fasciola gigantica among ruminants in Sudan.

Fasciola gigantica is a widespread parasite that causes neglected disease in livestock worldwide. Its high transmissibility and dispersion are attributed to its ability to infect intermediate snail hosts and adapt to various mammalian definitive hosts. This study investigated the variation and population dynamics of F. gigantica in cattle, sheep, and goats from three states in Sudan. Mitochondrial cytochrome c oxidase subunit I (COI) and NADH dehydrogenase subunit 1 (ND1) genes were sequenced successfully to examine intra and interspecific differences. ND1 exhibited higher diversity than COI, with 15 haplotypes and 10 haplotypes, respectively. Both genes had high haplotype diversity but low nucleotide diversity, with 21 and 11 polymorphic sites for ND1 and COI, respectively. Mismatch distribution analysis and neutrality tests revealed that F. gigantica from different host species was in a state of population expansion. Maximum likelihood phylogenetic trees and median networks revealed that F. gigantica in Sudan and other African countries had host-specific and country-specific lineages for both genes. The study also indicated that F. gigantica-infected small ruminants were evolutionarily distant, suggesting deep and historical interspecies adaptation.

Advances in diagnostic approaches to Fasciola infection in animals and humans: An overviews.

Fasciolosis, caused by Fasciola hepatica and F. gigantica, is an impediment to the livestock industry's expansion and has a massively negative socio-economic impact due to its widespread prevalence in livestock. It is a waterborne zoonosis affecting human populations in the countries where rural economies are associated with livestock rearing. Conventional diagnosis of Fasciola infection is done by detecting parasite eggs in the faeces of infected animals or by immunological methods. Accurate and quick immunodiagnosis of Fasciola infection in animals and humans is based on the detection of antibodies and specific antigens expressed in the prepatent stage of the parasite. Both molecular and serodiagnostic tests developed thus far have enhanced the reliability of Fasciola diagnosis in both man and animals but are not widely available in resource-poor nations. A pen-side diagnostic test based on a lateral flow assay or a DNA test like loop-mediated isothermal amplification (LAMP) would be simple, fast, and cost-effective, enabling clinicians to treat animals in a targeted manner and avoid the development of drug resistance to the limited flukicides. This review focuses on the recent advances made in the diagnosis of this parasite infection in animals and humans.

Human and Animal Fascioliasis: Origins and Worldwide Evolving Scenario.

Fascioliasis is a plant- and waterborne zoonotic parasitic disease caused by two trematode species: (i) Fasciola hepatica in Europe, Asia, Africa, the Americas, and Oceania and (ii) F. gigantica, which is restricted to Africa and Asia. Fasciolid liver flukes infect mainly herbivores as ruminants, equids, and camelids but also omnivore mammals as humans and swine and are transmitted by freshwater Lymnaeidae snail vectors. Two phases may be distinguished in fasciolid evolution. The long predomestication period includes the F. gigantica origin in east-southern Africa around the mid-Miocene, the F. hepatica origin in the Near-Middle East of Asia around the latest Miocene to Early Pliocene, and their subsequent local spread. The short postdomestication period includes the worldwide spread by human-guided movements of animals in the last 12,000 years and the more recent transoceanic anthropogenic introductions of F. hepatica into the Americas and Oceania and of F. gigantica into several large islands of the Pacific with ships transporting livestock in the last 500 years. The routes and chronology of the spreading waves followed by both fasciolids into the five continents are redefined on the basis of recently generated knowledge of human-guided movements of domesticated hosts. No local, zonal, or regional situation showing disagreement with historical records was found, although in a few world zones the available knowledge is still insufficient. The anthropogenically accelerated evolution of fasciolids allows us to call them "peridomestic endoparasites." The multidisciplinary implications for crucial aspects of the disease should therefore lead the present baseline update to be taken into account in future research studies.

Histopathological changes and oxidative stress associated with Fascioliasis in bovines.

Fascioliasis, a prevalent disease in livestock globally, is primarily caused by the trematode parasites Fasciola hepatica and Fasciola gigantica. This parasitic infection leads to significant economic repercussions. In this study, our objective was to gain insight into the pathophysiological consequences of Fascioliasis in cattle through the evaluation of metabolic, oxidative stress, and histological parameters. A thorough investigation was carried out on the liver of 197 bovines after their slaughter, which unveiled the occurrence of Fascioliasis, with a prevalence rate of 13.2% observed. The bovine that were infected exhibited notable increase in serum transaminases (ALT, AST, and ALP) and malondialdehyde (MDA) and catalase (CAT) while the decrease in glutathione (GSH) and superoxide dismutase (SOD) levels. The lipid profile analysis of infected cattle revealed alterations in the cholesterol and triglyceride levels. Moreover, the histopathological examination revealed a range of hepatic lesions associated with Fascioliasis, including necrosis, inflammation, fibrosis, and proliferative alterations. The bile ducts also displayed distinct pathological changes, including hyperplasia, thickening, and edema, and harbored various developmental stages of Fasciola spp. highlighting the parasitic infestation's effects on the biliary system. These results highlight the serious effects of Fascioliasis on lipid metabolism and the oxidative damage that is induced in the livers of cattle. Thus, Fasciola infestation in bovine causes alteration in biochemical and antioxidant activities, which are considered as important factors in the diagnosis of Fascioliasis.

Fasciola gigantica vaccine construct: an in silico approach towards identification and design of a multi-epitope subunit vaccine using calcium binding EF-hand proteins.

Continuous attempts have been made to pinpoint candidate vaccine molecules and evaluate their effectiveness in order to commercialise such vaccines for the treatment of tropical fascioliasis in livestock. The pathophysiology of fascioliasis can be related to liver damage brought on by immature flukes that migrate and feed, as well as immunological reactions to chemicals produced by the parasites and alarm signals brought on by tissue damage. Future research should, in our opinion, concentrate on the biology of invasive parasites and the resulting immune responses, particularly in the early stages of infection. The goal of the current study was to use the calcium-binding proteins from F. gigantica to create a multi-epitope subunit vaccine. The adjuvant, B-cell epitopes, CTL epitopes, and HTL epitopes that make up the vaccine construct are all connected by certain linkers. The antigenicity, allergenicity, and physiochemical properties of the vaccine construct were examined. The vaccine construct was docked with toll-like receptor 2, and simulations of the molecular dynamics of the complex's stability, interaction, and dynamics were run. After performing in silico cloning and immunosimulation, it was discovered that the construct was suitable for further investigation. New vaccination technologies and adjuvant development are advancing our food safety procedures since vaccines are seen as safe and are accepted by the user community. This research is also applicable to the F. hepatica system.

Emerging Human Fascioliasis: A Retrospective Study of Epidemiological Findings in Dali, Yunnan Province, China (2012-2021).

BACKGROUND Human fascioliasis is an emerging zoonotic disease caused by the trematodes, or flatworms, Fasciola hepatica and Fasciola gigantica, also known as liver flukes. This retrospective study aimed to report the epidemiological findings in 95 cases of human fascioliasis in Dali, Yunnan Province, southwestern China, diagnosed between 2012 and 2021. MATERIAL AND METHODS The epidemiologic and clinical data of 95 patients diagnosed with human fascioliasis in Dali area from January 2012 to December 2021 were collected and retrospectively analyzed. The diagnosis of fascioliasis was based on the Chinese National Standard of Diagnosis of Fascioliasis (WS/T566-2017). RESULTS The mean age of patients was 38.54±15.68 years, and there were more female patients than male (61.05% vs 38.95%). The high-incidence seasons were identified as summer and autumn. The patients with human fascioliasis lived in pastoral areas or were infected F. gigantica by consuming contaminated vegetables or water containing metacercaria. Meanwhile, human fascioliasis was diagnosed by positive serologic tests (1: 640), and Fasciola eggs (144-180×73-96 µm) were detected in stool samples of 6 patients. The most common clinical features were abdominal pain (70.53%), accompanied by elevated eosinophils in 89.5% of these patients. Antiparasitic treatment with triclabendazole at 10 mg/kg/day for 2 days led to symptom relief in all patients. CONCLUSIONS The findings from this observational epidemiological study have highlighted the importance of recognizing, diagnosing, and managing fascioliasis, which is an emerging zoonosis associated with increased human proximity to plant-eating domestic and farmed animals.

Reconstruction of the TGF-ß signaling pathway of Fasciola gigantica.

In the present study, we reconstructed the transforming growth factor beta (TGF-ß) signaling pathway for Fasciola gigantica, which is a neglected tropical pathogen. We defined the components involved in the TGF-ß signaling pathway and investigated the transcription profiles of these genes for all developmental stages of F. gigantica. In addition, the presence of these components in excretory and secretory products (FgESP) was predicted via signal peptide annotation. The core components of the TGF-ß signaling pathway have been detected in F. gigantica; classical and nonclassical single transduction pathways were constructed. Four ligands have been detected, which may mediate the TGF-ß signaling pathway and BMP signaling pathway. Two ligand-binding type II receptors were detected, and inhibitory Smad7 was not detected. TLP, BMP-3, BMP-1, and ActRIb showed higher transcription in 42-day juvenile and 70-day juvenile, while ActRIIa, Smad1, ActRIIb, Smad8, KAT2B, and PP2A showed higher transcription in egg. TLM, Ski, Smad6, BMPRI, p70S6K, Smad2, Smad3, TgfßRI, Smad4, and p300 showed higher transcription in metacercariae. Four ligands, 2 receptors and 3 Smads are predicted to be present in the FgESP, suggesting their potential extrinsic function. This study should help to understand signal transduction in the TGF-ß signaling pathway in F. gigantica. In addition, this study helps to illustrate the complex mechanisms involved in developmental processes and F. gigantica - host interaction and paves the way for further characterization of the signaling pathway in trematodes.

Differentiating paramphistome species in cattle using DNA barcoding coupled with high-resolution melting analysis (Bar-HRM).

Paramphistomosis is caused by paramphistome or amphistome parasites, including Fischoederius elongatus, Gastrothylax crumenifer, Orthocoelium parvipapillatum, and Paramphistomum epiclitum. The control and prevention of these parasite outbreaks are difficult because of the wide occurrence of these species. Besides, the clinical manifestations and their egg characteristics are similar to those of other intestinal flukes in the paramphistome group, leading to misdiagnosis. Here, we employed DNA barcoding using NADH dehydrogenase (ubiquinone, alpha 1) (ND1) and cytochrome c oxidase subunit I (COI), coupled with high-resolution melting analysis (Bar-HRM), for species differentiation. As a result, ParND1_3 and ParCOI4 resulted in positive amplification in the paramphistomes and Fasciola gigantica, with significantly different melting curves for each species. The melting temperatures of each species obtained clearly differed. Regarding sensitivity, the limit of detection (LoD) for all species of paramphistomes was 1 pg/µl. Our findings suggest that Bar-HRM using ParND1_3 is highly suitable for the differentiation of paramphistome species. This approach can be used in parasite detection and epidemiological studies in cattle.

First morphometric and molecular characterization of Fasciola spp. in Northwest Tunisia.

The aim of this study was to characterize the Tunisian Fasciola spp. flukes by morphometric and molecular analyses. Flukes were collected from livers of sheep slaughtered in Sejnane slaughterhouses (Bizerte gouvernorate, Northwest Tunisia) between January and March 2021.Five morphometric parameters were determined for all the liver flukes, as follows: (i) total body length (BL), (ii) distance between ventral sucker and the tail (VS-T), (iii) distance between oral sucker and ventral sucker (OS-VS), (iv) abdomen diameter (AD), (v) tail diameter (TD) and the body length to width ratio (BL/BW). Molecular identification of the fluke specimens was carried out by polymerase chain reaction, restriction fragment polymorphism (PCR-RFLP) of a 680 bp sequence of the internal transcribes spacer 1 (ITS1) gene and by amplification, sequencing, and phylogenetic analysis of a 500 bp sequence of the ITS2 gene. Morphometric measurements showed that the mean of the total body length of the adult flukes was 21.1 ± 2.7 mm with minimum and maximum lengths of 13 and 31 mm, respectively. The PCR-RFLP analysis revealed a single profile consisting of three bands of approximately 370, 100, and 60 bp. Fasciola sequences described in the present study (GenBank numbers: OQ457027 and OQ457028) showed 99.58-100% identity to Fasciola hepatica. In conclusion, the results of this study show that molecular and phylogenetic analyses confirm the presence of a single species of F. hepatica in the Sejnane region Northwest of Tunisia. However, further studies are needed to identify the occurrence of Fasciola species in other Tunisian regions.

Efficacy of flukicides on Fasciola gigantica, a food-borne zoonotic helminth affecting livestock in Bangladesh.

Fasciola gigantica, the causative agent of tropical fasciolosis, is a food-borne zoonotic trematode that affects around 80% livestock of Bangladesh. Triclabendazole (TCBZ), nitroxynil (NTON) and oxyclozanide (OCZN) are frequently used against fascioliasis; however, the current status of potency of these flukicides was unknown. In this study, in vitro efficacy of TCBZ, NTON and OCZN at various concentrations on F. gigantica has been evaluated by relative motility (RM), morphological distortions of apical cone through an inverted microscope, architectural and ultra-structural changes through histopathological and scanning electron microscopy (SEM). It is observed that TCBZ, NTON and OCZN at higher concentrations significantly (P < 0.05) reduced RM of the flukes compared to untreated control. NTON at 150 µg mL−1 was the most potent to reduce the motility within 4 h whereas TCBZ and OCZN were much delayed. Histopathological changes showed swollen, extensive cracking, numerous vacuoles and splitting of the tegument surrounding the spines; spine dislodged from its socket in treated flukes compared to untreated worms. Histopathological changes were more conspicuous at higher doses of TCBZ, NTON and OCZN. SEM has shown the disruption of the apical cone, apart from swelling of the tegument on the ventral surface corrugation and disruption of the ventral apical cone. All these changes indicate that NTON is the most potent in killing flukes in vitro among the tested flukicides and suggest the presence of TCBZ-resistant fluke populations in Bangladesh. It is imperative to explore the in vivo effects of these flukicides and subsequently their molecular mechanisms.

Superoxide dismutase inhibits cytotoxic killing of Fasciola gigantica newly excysted juveniles expressed by sheep invitro.

Fasciola gigantica faces a series of threats from various free radicals produced by the host immune system during its invasion through the abdominal cavity and establishment in the bile duct of ruminants, limiting the fluke viability. The role of the superoxide radical produced by Muzaffarnagari sheep immune effector cells against F. gigantica newly excysted juveniles (NEJs) is highlighted in this study, as is the critical role of superoxide dismutase enzyme (SOD) in dismutation of superoxide radicals derived from host immune effector cells in vitro. Three concentrations of the ovine immune effector cells viz. 2.5, 5, and 10 × 106 cells were tested for their ability to induced cytotoxic killing of the parasite. All the three cell concentrations caused significant (p < 0.01) cytotoxic killing of NEJs in comparison to the control groups. Also, reduction of the immune effector cell concentration directly correlates with the NEJs killing. Attachment of immune effector cells to the parasite tegument in the presence of anti-F. gigantica antibodies was found to be critical in inducing NEJs killing via antibody-dependent cell-mediated cytotoxicity (ADCC). However, the addition of SOD greatly inhibits cytotoxic killing of NEJs, demonstrating the importance of SOD enzyme in fluke survival and parasite evasion of the host immunity. Thus, F. gigantica SOD warrants a promising candidate for immunoprophylactic studies in ruminants against the tropical liver fluke.

A global phosphoproteomics analysis of adult Fasciola gigantica by LC-MS/MS.

Protein phosphorylation plays key roles in a variety of essential cellular processes. Fasciola gigantica is a tropical liver fluke causing hepatobiliary disease fascioliasis, leading to human health threats and heavy economic losses. Although the genome and protein kinases of F. gigantica provided new insights to understand the molecular biology and etiology of this parasite, there is scant knowledge of protein phosphorylation events in F. gigantica. In this study, we characterized the global phosphoproteomics of adult F. gigantica by phosphopeptide enrichment-based LC-MS/MS, a high-throughput analysis to maximize the detection of a large repertoire of phosphoproteins and phosphosites. A total of 1030 phosphopeptides with 1244 phosphosites representing 635 F. gigantica phosphoproteins were identified. The phosphoproteins were involved in a wide variety of biological processes including cellular, metabolic, and single-organism processes. Meanwhile, these proteins were found predominantly in cellular components like membranes and organelles with molecular functions of binding (51.3%) and catalytic activity (40.6%). The KEGG annotation inferred that the most enriched pathways of the phosphoproteins included tight junction, spliceosome, and RNA transport (each one contains 15 identified proteins). Combining the reports in other protozoa and helminths, the phosphoproteins identified in this work play roles in metabolic regulation and signal transduction. To our knowledge, this work performed the first global phosphoproteomics analysis of adult F. gigantica, which provides valuable information for development of intervention strategies for fascioliasis.

Effect of primary and secondary Fasciola gigantica infection on specific IgG responses, hepatic enzyme levels and weight gain in buffaloes.

Buffaloes, as highly susceptible definitive hosts of Fasciola gigantica, suffer from a high infection rate of fasciolosis, which causes enormous economic losses. Repeat infection is responsible for this high rate; thus, elucidating the protective immunity mechanism in repeat infection is decisive in fasciolosis prevention. Herein, a secondary experimental infection model was established to preliminarily reveal the protective immunity that occurs in repeat infection. In brief, animals were assigned to three groups: group A (uninfected control), group B (primary infection) and group C (secondary infection). Buffaloes were autopsied 20 weeks post-infection for measurements of the recovered flukes and hepatic examination. In addition, the detection of specific antibody (IgG) responses to F. gigantica excretory-secretory product (FgESP) throughout the whole period and weight gain throughout the first 4 months as a percentage (%) of the starting weight were also determined. The serum hepatic enzyme gamma glutathione transferase (GGT) levels were monitored to assess hepatic damage throughout the study period. Infection establishment was compared between group B and group C. Similar specific IgG patterns were observed between group B and group C, and hepatic damage was more severe in group C than group B. Significant differences in weight gain as a percentage of the start weight were observed between group A and group B at the 3rd and 4th months postprimary infection, while significant differences were not observed between group A and group C or group B and group C. Our results suggest that challenge infection cannot induce resistance against F. gigantica in buffaloes, which is consistent with the protective immunity against Fasciola hepatica reinfection observed in sheep and goats.

Identification and expression of a transforming growth factor beta (TGF-ß) homologue in the tropical liver fluke Fasciola gigantica.

Liver flukes, Fasciola spp., are veterinary and medically important parasites infecting numerous species of economically important animals in addition to humans on a global scale. The components of transforming growth factor beta (TGF-ß) signalling are widely distributed throughout the animal kingdom and are considerably conserved. Through shared common signal transduction mechanisms, crosstalk of TGF-ß signalling between a host and the parasite during infection is possible. Herein, we have identified and undertaken the molecular characterisation of a putative TGF-ß homologue from the tropical liver fluke F. gigantica (FgTLM). A FgTLM cDNA was 3557 bp in length, it encoded for 620 amino acid polypeptide which consisted of 494 amino acids of prodomain and 126 amino acids comprising the mature protein. FgTLM displayed characteristic structures of mammalian TGF-ß ligands that were unique to the inhibin-ß chain, monomer of activin. A phylogenetic analysis revealed the high degree of conservation with TGF-ß molecules from trematode species. Interestingly, the sequence of amino acid in the active domain of FgTLM was completely identical to FhTLM from F. hepatica. FgTLM expressed throughout the lifecycle of F. gigantica but was highly expressed in developmental active stages. The dynamics of expression of FgTLM during the developmental stages of F. gigantica was comparable to the pattern of TGF-ß expression in F. hepatica. Our findings demonstrated that FgTLM exhibits a high level of similarity to FhTLM in the context of both amino acid sequence and the life stage expression patterns. These similarities underline the possibility that the FgTLM molecule might have the same properties and functions as FhTLM in biological processes of the immature parasites and host immune evasion. Consequently, the specific biological functions of FgTLM on either parasite or relevant hosts need to be defined experimentally.

Body condition scores, fluke intensity, liver pathology, and carcass quality of different dairy cattle genotypes infected with Fasciola species at high throughput abattoirs in South Africa.

Milk is an essential commodity whose demand far exceeds supply. However, dairy animal productivity is constantly hampered by parasitic diseases such as fasciolosis, affecting milk production. Despite the negative impact of liver fluke on milk production, there is little information on liver fluke infection and associated abattoir losses (body weight, condition score, liver pathology, and carcass quality) in culled dairy cattle. This study aimed to determine body condition scores, fluke intensity, liver pathology, and carcass quality of different cattle genotypes infected with Fasciola species at three commercial abattoirs. A longitudinal study was conducted from September 2019 to October 2020 to determine body condition score, liver fluke intensity, liver pathology in 3065 dairy cattle slaughtered in CA1, CA2, and CA3, of the Eastern Cape Province South Africa. Liver fluke intensity significantly increased with cattle age (P < 0.0001). Cattle ≥ 7 years old (59.93 ± 6.42) and those 4 to 6 years old (49.78 ± 9.98) had higher infection than those 2 to 3 years old (27.55 ± 13.68). The liver fluke infection was significantly (P < 0.001) the highest when sampling was conducted in summer, followed by autumn and winter, and least for spring. The differences in carcass weights or body condition scores decreased by 0.99 units (P < 0.0001) or 0.97 units (P < 0.0001) respectively. Therefore, this study suggests that fluke infection could be responsible for considerable economic and production losses mainly due to condemnation and weight loss in dairy cattle. This study recommended a combination of holistic and grazing management to control infection rates in dairy herds.

Phylogenetic Characteristics of Fasciola hepatica Isolated from a Korean Patient.

Fascioliasis is a parasitic infection caused by liver flukes. Although several cases have been reported in Korea, phylogenetic analysis of isolates is lacking. In this study, a 66-year-old woman with right upper quadrant (RUQ) abdominal pain was diagnosed as fascioliasis involving abdominal muscle by imaging study. She received praziquantel treatment, but symptoms were not improved. Lateral movement of the abscess lesion was followed. Trematode parasite was surgically removed from the patient's rectus abdominis muscle. The fluke was identified as Fasciola hepatica based on sequence analysis of 18S rDNA. To determine the phylogenetic position of this Fasciola strain (named Korean Fasciola 1; KF1), the cox1 gene (273 bp) was analyzed and compared with the genes of 17 F. hepatica strains isolated from cows, sheep, goats, and humans from various countries. Phylogenetic analysis showed that KF1 was closely related with the isolates from China goat.

Geography and ecology of invasive Pseudosuccinea columella (Gastropoda: Lymnaeidae) and implications in the transmission of Fasciola species (Digenea: Fasciolidae) - a review.

Pseudosuccinea columella is considered invasive and has become an important intermediate host of both Fasciola species in many regions of the world. This systematic review assessed the geographical distribution of P. columella, and its implications in the transmission of Fasciola hepatica and Fasciola gigantica, globally. A literature search was conducted on Google Scholar, JSTOR and PubMed databases using Boolean operators in combination with predetermined search terms for thematic analysis. Results show that P. columella has been documented in 22 countries from Europe (3), Africa (8), Oceania (2), North America (3) and South America (6). Furthermore, this snail species has shown to adapt to and inhabit a vast array of freshwater bodies including thermal lakes and ditches with acidic soils. Studies showed that P. columella transmits F. hepatica, with natural and experimental infections documented in sub-Saharan Africa, Europe, South America and North America. Experimental infection studies in Cuba showed the presence of P. columella populations resistant to F. hepatica infection. Furthermore, some populations of this invasive snail collected from F. hepatica endemic locations in Brazil, Venezuela, Australia, South Africa, Colombia and Argentina were found without Fasciola infection. As a result, the role played by this snail in the transmission of Fasciola spp. in these endemic areas is still uncertain. Therefore, further studies to detect natural infections are needed in regions/countries where the snail is deemed invasive to better understand the veterinary and public health importance of this snail species in Fasciola-endemic areas and determine the global dispersion of resistant populations of P. columella.