An innovative approach to control fish-borne zoonotic metacercarial infections in aquaculture by utilizing nanoparticles.

Fish-borne zoonotic trematodes (FBZTs) pose significant health risks and economic challenges worldwide. This study investigated the prevalence of encysted metacercariae (EMCs) in Nile tilapia (Oreochromis niloticus) from two Egyptian governorates and evaluated the antiparasitic efficacy of chitosan, silver, and selenium nanoparticles against these parasites. A cross-sectional analysis of 453 O. niloticus specimens revealed an overall EMC prevalence of 40.8%, with infection rates of 34.11% in Giza and 49.5% in Dakahlia. Clinostomid and Prohemistomid metacercariae were the most common, with mixed infections observed. Transmission electron microscopy characterized the synthesized nanoparticles, showing average diameters of 9.6-18.7 nm for chitosan, 13.2-19.8 nm for selenium, and 11.7-15.1 nm for silver nanoparticles. In vitro antiparasitic assays demonstrated varying efficacies among the nanoparticles. Against Clinostomum spp. metacercariae, chitosan nanoparticles showed the highest potency, achieving LC50 at 66 µg/ml after 30 min and LC90 at 100 µg/ml after 120 min. For Prohemistomum vivax EMCs, chitosan nanoparticles exhibited superior efficacy, achieving LC50 at 8 µg/ml after 1 h and LC90 at 16 µg/ml after 2 h. Silver and selenium nanoparticles showed lower efficacy for both parasite species. Scanning electron microscopy revealed significant ultrastructural damage to the parasite tegument following nanoparticle exposure, including disappearance of transverse ridges, integument shrinkage, and formation of blebs. This study provided valuable insights into the prevalence of FBZTs in Egyptian Nile tilapia and demonstrated the potential of nanoparticles, particularly chitosan, as effective antiparasitic agents. These findings pave the way for developing novel, targeted strategies to control fish-borne zoonotic trematodes, potentially reducing their impact on public health and aquaculture economies.

Evaluation of Praziquantel effectiveness in treating Nile tilapia clinostomid infections and its relationships to fish health and water quality : By.

This study aimed to conduct a multidisciplinary investigation integrating detailed morphology, molecular characterization, water parameters, histopathology alteration, and the trials of treatment of Clinostomum spp. In this study, 300 Nile tilapia (Oreochromis niloticus) were collected from the farmed and wild Nile River at Al Bahr Al Aazam, Giza Governorate to assess Clinostomid infection prevalence. Fish and water samples were collected from private fish farms, and water drains at Dakahlia, and Giza, Egypt. Analysis of the water revealed inadequate water quality, particularly in the fish farms. Snails and piscivorous birds were abundant at fish collection sites. The recovered Clinostomid MCs morphological characteristics and COI gene sequence analysis identified them as Clinostomum complanatum, C. phalacrocoracis, and Euclinostomum heterostomum. Clinostomid MCs disturbed the fish's hematological and biochemical blood parameters. Bath treatment of parasitized fish with praziquantel (2 mg/L for 24 h) revealed a significant reduction in the number of vital MCs vs. infected fish (non-treated). Praziquantel (PZQ) is an effective and safe therapy for controlling Clinostomid infections affecting farmed Nile tilapia. The current findings indicate a link between poor environmental conditions and Clinostomum infections in tilapia. The study highlights the impacts of Clinostomid MCs on fish health and recommends bath treatment with PZQ as an efficient control method for these dangerous parasites to protect human and fish health.

Investigating dynamics, etiology, pathology, and therapeutic interventions of Caligus clemensi and Vibrio alginolyticus co-infection in farmed marine fish.

This study investigated a disease outbreak characterized by caligid copepod infestations and subsequent secondary bacterial infections in European seabass (Dicentrarchus labrax) and flathead grey mullet (Mugil cephalus) cultivated at a private facility in the Deeba Triangle region of Egypt. Moribund fish displayed brown spots on the skin, tongue, and gills, along with lethargy and excess mucus. The fish suffered severe infections, exhibiting external hemorrhages, ulcers, and ascites. The fish had pale, enlarged livers with hemorrhaging. Comprehensive parasitological, bacteriological, molecular, immunity and histopathological analyses were conducted to identify the etiological agents and pathological changes. Caligid copepod infestation was observed in wet mounts from the buccal and branchial cavities of all examined fish, and the caligids were identified as Caligus clemensi through COI gene sequencing and phylogenetic analysis. Vibrio alginolyticus was confirmed as a secondary bacterial infection through biochemical tests, recA gene sequencing, and phylogenetic analyses. Antibiotic susceptibility testing revealed resistance to ß-lactams, aminoglycosides, and trimethoprim-sulfamethoxazole in V. alginolyticus isolates. Upregulation of the inflammatory marker IL-1ß in gill and skin tissues indicated a robust cell-mediated immune response against the pathogens. Histopathological examination revealed severe tissue damage, hyperplasia, hemorrhage, and congestion in the gills, along with hepatocellular degeneration and steatosis in the liver, providing initial insights into this outbreak. A comprehensive therapeutic regimen was implemented, comprising prolonged hydrogen peroxide immersion baths, followed by the application of the nature-identical plant-based compound Lice-less and probiotic Sanolife Pro-W supplementation. This integrated approach effectively eliminated C. clemensi infestations, controlled secondary bacterial infections, and restored fish health, reducing morbidity and mortality rates to minimal levels.

Morphomolecular identification of heavy parasitic typhlitis in layer flocks: tissue response and cell-mediated reaction.

BACKGROUND: Heterakis gallinarum (H. gallinarum) is a common poultry parasite that can be found in the ceca of many gallinaceous bird species, causing minor pathology and reduced weight gain. Most infections go unnoticed in commercial flocks due to the dependence on fecal egg counts, which are prone to false-negative diagnoses. Furthermore, there is a lack of research on gastrointestinal nematodes that use molecular identification methods, which could be essential for rapid diagnosis and developing efficient control approaches. As a result, the study aimed to look at the cause of mortality in layer chickens induced by H. gallinarum in Egyptian poultry farms using morphological, ultrastructural, and molecular characterization. Histopathological, immunohistochemical, and cell-mediated immune responses from damaged cecal tissues were also examined. RESULTS: Seventy bird samples from ten-layer flocks of different breeds (Native, white, and brown layers) suffering from diarrhea, decreased egg output, and emaciation were collected. Cecal samples were collected from affected and non-affected birds and were examined for parasitic diseases using light and a scanning electron microscope. The mitochondrial cytochrome oxidase 1 (COX1) gene was used to characterize H. gallinarum. Our results showed that the collected nematodal worms were identified as H. gallinarum (male and female), further confirmed by COX1 gene amplification and sequence alignment. Gene expression analysis of the inflammatory markers in infected tissues showed a significant up-regulation of IL-2, IFN-γ, TLR-4, and IL-1ß and a significant down-regulation of the anti-inflammatory IL-10. The mRNA level of the apoptotic cas-3 revealed apoptotic activity among the H. gallinarum samples compared to the control group. CONCLUSIONS: Our results implemented the use of molecular methods for the diagnosis of Heterakis, and this is the first report showing the tissue immune response following infection in layers: upregulation of IL-1ß, IFN-γ, Il-2, and TLR-4, while down-regulation of anti-inflammatory IL-10 in cecal tissue, Cas-3 apoptotic activity and Nuclear factor-κB (NF-κB)activity with immunophenotyping of T-cells in Heterakis infected tissue.

Dasyrhynchus giganteus plerocercoids encysting in the musculature of Indian halibut (Psettodes erumei): seasonal prevalence, morpho-molecular characterization, and histopathological alterations.

This study investigated the prevalence, morphology, molecular identification, and histopathological effects of larval tapeworms (plerocercoids) infecting the skeletal muscles of the Indian halibut (Psettodes erumei) collected from the coastal waters of the Arabian Gulf. Numerous oval or round blastocysts, measuring 13-26 mm, were found embedded within the muscular tissues of the Indian halibut, rendering the fish unsuitable for human consumption. Morphological and molecular analyses identified the plerocercoids as Dasyrhynchus giganteus (family Dasyrhynchidae), with an overall prevalence of 15.4%. The seasonal prevalence was the highest in summer (14.6%), followed by spring (10.6%), winter (4.4%), and autumn (3.5%). Infection rates increased with fish size. Histopathological examination revealed fibrous connective tissue capsules surrounding the larvae, causing muscular atrophy and degenerative changes, with few inflammatory eosinophilic cells. Molecular and phylogenetic analysis of the 28S rDNA gene sequences confirmed the specimens as D. giganteus, clustered closely with other sequences of D. giganteus with 100% bootstrap values. This study provided valuable insights into the parasitic infection dynamics, seasonal variation, molecular identification, and histopathological effects, highlighting the importance of monitoring fish for food safety and public health implications.

Immunological and molecular evaluation of zoonotic metacercarial infection in freshwater fish: A cross-sectional analysis.

Improperly cooked fish, carrying active metacercariae (MCs), can pose a significant risk for transmitting fish-borne zoonotic trematodes (FBZTs) to human consumers. This study aimed to enhance our understanding of FBZTs by conducting a comprehensive cross-sectional analysis involving various fish species, such as Nile tilapia (Oreochromis niloticus), African catfish (Clarias gariepinus), and red-belly tilapia (Tilapia zillii). These fish specimens were collected from distinct Egyptian governorates, specifically Giza, Kafr al-Shaykh, and Fayoum. The recovered flukes from experimentally infected domestic pigeons were identified as Prohemistomum vivax, Haplorchis pumilio, and Pygidiopsis genata based on morphological features. Furthermore, the identity of the retrieved adult flukes was confirmed using three species-specific primers for PCR amplification and sequencing analysis of the ITS rDNA region and have been deposited in GenBank with the following accession numbers: P. vivax (OR291421.1 and OR291422.1), P. genata (OP099561.1), and H. pumilio (OM439581.1-OP090510.1). Quantitative real-time PCR targeting the immunological genes Tumor Necrosis Factor-alpha (TNF-alpha) and Interleukin-1 (IL-1Β) was employed to compare the cellular immune response between infected with EMCs and uninfected O. niloticus. The results indicated a significant increase in TNF- and IL-1Β levels in FBZTs-infected vs un-infected fishes. Importantly, the presence of adult flukes and EMCs led to substantial histological alterations in both experimentally infected pigeons and naturally infected fish tissues. These changes included the necrosis of fish muscle bundles and a pronounced inflammatory reaction with muscular necrosis in the digestive tracts of experimentally infected pigeons.

Comparative biotoxicity study for identifying better alternative insecticide especially green nano-emulsion which used as mosquitocides.

This research work was planned to test biosafety of different nanomaterials on the different animals models. These nanoparticles were previously used as potential insecticides of mosquito larvae. The biosafety of these nanoproducts were evaluated on certain organs of non target animals that associated with mosquito breeding sites in Egypt. Animal organs such as the kidneys of rats, toads, and the fish's spleen were used as models to study the biological toxicity of these nanomaterials. After 30 days of the animals receiving the nanomaterials in their water supply, different cell mediated immune cells were assessed in these tissues. Both TNF-α and BAX immuno-expression were also used as immunohistochemical markers. Histopathology was conducted to detect the effect of the tested nanoproducts at the tissue level of the liver and kidneys of both the rats and toads. Green nanoemulsion of the lavender essential oil was relatively more effective, safe, and biodegradable to be used as insecticides against mosquito larvae than the metal-based nanomaterials.

First report of Kudoa species (Myxozoa, Multivalvulida) infection in purple-spotted Bigeye (Priacanthus tayenus) from the Saudi Arabian Gulf.

The purple-spotted bigeye, Priacanthus tayenus, is a marine benthic fish native to the Indian and Pacific Oceans, including the Arabian Gulf in Saudi Arabia. This study identified a myxozoan parasite infecting wild P. tayenus from the Saudi Arabian Gulf. These parasites produced spherical to ovoid-shaped, white plasmodia enclosed within pseudocysts in the fish musculature. The annual infection rate was 5.1%, with the highest prevalence in summer (7.6%), followed by spring (6%), and autumn (2.5%), while no infections were observed in winter. The number of plasmodia per fish ranged from 100 to 150 (135.1 ± 16.2). Their dimensions were 4-4.7 mm (4.3 ± 0.3 mm) in length and 4.5-7 mm (6 ± 1.1 mm) in width. Milky-colored exudates within the plasmodia contained mature spores measuring 8-9 µm (8.6 ± 0.4 µm) x 6-7.5 µm (6.9 ± 0.5 µm). The polar capsules of the spores exhibited dimensions of 2-5 µm (3.5 ± 0.5 µm) x 2.5-4.5 µm (3 ± 0.45 µm). Both morphological and genetic analyses confirmed these plasmodia as a novel Kudoa species. Histopathological examination revealed atrophy in the surrounding muscles without an inflammatory response. This study documents the first occurrence of a novel Kudoa sp. in P. tayenus at the Jubail landing site in Saudi Arabia, emphasizing the need for further surveillance and investigations to elucidate its pathogenesis and implications for wild fish stocks.

Coinfection of the gut with protozoal and metazoal parasites in broiler and laying chickens.

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-1ß, 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.

Toxascaris leonina infected domestic cat (Felis catus) in Egypt; PCR-based molecular characterization of nematode eggs: a potential hazards to human health.

This molecular-epidemiological study was conducted in several locations in Cairo and Giza Governorates in domestic cats (Felis catus) to detect the most common intestinal helminths in feces and molecularly characterize this nematode. So, three hundred domestic cats were admitted to different clinics around Cairo and Giza Governorates with severe diarrhea, even watery, between January 2023 and April 2023. The ages of the cats ranged from 1 to 2.5 years old. Blood, sera, and urine samples were collected for further investigation of the health condition of the animals. Toxascaris leonina was the major intestinal parasite found in cat stools, with a prevalence rate of 5% (15 cats). Toxascaris leonina (T. leonina) eggs had oval elliptical surfaces and thick cuticles. An embryo was located inside the smooth outer shell wall of the shell. The animals suffer from normocytic normochromic anemia with leukocytosis, relative lymphocytosis, and thrombocytopenia. The amplification of the ITS-rDNA region from the ascaridoid nematodes was successfully performed using NC5 and NC2 primers. The PCR product of the ITS-rDNA fragment was sequenced and yielded 860 bp. The accession number of the sequenced ITS-rDNA region was OQ735413, submitted to Gene Bank, and based on the blast analysis of NCBI, the current ascaridoid nematode proved to be genetically related to the family Ascarididae and identified as T. leonina.

Impact of Eimeria tenella experimental Infection on intestinal and splenic reaction of broiler chickens.

This work assesses the cell-mediated immune reaction IL-6, TNF-α, and IFN-γ of experimentally challenged broiler chicken with Eimeria tenella (E. tenella). Therefore, ninety, 2-weeks-old healthy broiler chicks were allocated as eighty chicks infected orally with 2.5 × 104 E. tenella sporulated oocysts, and the other ten birds were kept as control negative birds. Post-challenge, mortality rate, symptoms, oocysts shedding, and lesion score were evaluated. Tissue samples (cecum and spleen) were collected at 0, 4, 8, and 12 days post-infection (dpi). Ten chickens were ethically slaughtered at 0, 4, 8, and 12 days post-infection, as well as two birds from the negative control group; parts from cecal and spleen samples were kept in cryopreservation containers, and other parts were preserved in formaline 10% for further investigation. The evaluated genes (IL-6, TNF-α, and IFN-γ) were normal at 0 days and upregulated at 4 and 8 days, which reached maximum upregulation at eight dpi. The histopathological examination of the ceca and spleen were evaluated before and after challenge. It could be concluded that E. tenella revealed direct severe macroscopic and microscopic changes in cecal tissues and indirectly induced alteration in splenic tissues, resulting in upregulation of different cell mediated immune response in cecum and spleen in relation to the experimental period.

Development of silver nano-based indirect ELISA and Dot-ELISA methods for serological diagnosis of a bacterial fish pathogen Aeromonas veronii.

Rapid and accurate detection of bacterial pathogens is critical in controlling disease outbreaks affecting farmed fish. The present study aimed to develop a novel serological diagnostic approach using nano­silver based Enzyme-linked immunosorbent assay (ELISA) for speedy detection of Aeromonas veronii infections in Nile tilapia. A. veronii isolates used in ELISA assays were recovered from moribund Nile tilapia during a disease outbreak in a private fish farm in Egypt. A. veronii isolates were identified based on alignment analysis of the gyrB and 16S rRNA gene sequences. A. veronii antisera used in ELISA assays were prepared in tilapia, and the bacterial antigens were formalin-killed. The cut-off values were 0.46 and 0.48 in traditional and nano-based ELISA. There were no cross-reactions with bacterial isolates (Aeromonas hydrophila, Aeromonas caviae, Aeromonas sobria, Pseudomonas fluorescens, and Vibrio vulnificus). The lowest antigen concentration that produced positive results after checkerboard titration in indirect-ELISA (i-ELISA) and dot ELISA was 15 µg and 250 ng of prepared antigen, respectively. Nano-ELISA and nano-based dot-ELISA antigen concentration was 10 µg and 100 ng, respectively. Sera concentration was 1:100 in indirect-ELISA and dot-ELISA, while it was 1:50 in nano-based ELISA and nano dot-ELISA. The i-ELISA successfully detected anti-Aeromonas IgG antibodies with 83.33% sensitivity and 66.67% specificity, while in the dot-ELISA, the sensitivity and specificity were 83.33% and 100%, respectively. Nano dot-ELISA had 100% sensitivity, specificity, and accuracy. Nano dot-ELISA assays have higher specificity, sensitivity, and accuracy than traditional ELISAs in detecting A. veronii. Further studies are needed to develop a rapid test kit for on-site field diagnosis.

The immune responses of Oreochromis niloticus against Prohemistomum vivax encysted metacercariae infection with the evaluation of different biomarkers stressors.

This study aimed at evaluating the immunological status of Oreochromis niloticus (O. niloticus); so, a total of 120 O. niloticus were collected from different farms located in Kafr El-Sheikh Governorate in Egypt during the period from January 2021 to January 2022. The fish were surveyed for commonly encysted metacercariae present in different organs such as gills, spleen, liver, kidney, and muscles. The collected encysted metacercariae were of the family Cyathocotylidae (Prohemistomum vivax) with a prevalence of 25%. Different cell-mediated immune responses such as Major histocompatibility class II alpha (MHC-IIα), Toll-like receptor 7 (TLR-7), Interleukin (IL-8), and Clusters of differentiation 4 (CD4) were assessed in different organs such as gills, spleen, liver, kidney, and muscles which revealed an elevation in different genes in infected organs as a reaction from the body against parasitic infection. In addition, the liver enzymes; aspartate aminotransferase (AST), and alanine aminotransferase (ALT), were assessed in the serum of O. niloticus as well as blood glucose, cortisol levels, and lysozyme activity were estimated to record higher levels in the infected fish in comparison with the control non-infected ones.

Virulence of Babesia bigemina in infected cattle (Bos taurus): Molecular and immunological studies.

This study examined 400 tick-infested cattle from the following four governorates in Egypt: Faiyum, Beni Suef, Giza, and Minya. These cattle were examined for blood parasites between January 2021 and April 2022. The infected cattle were classified into four groups based on tick infestations and clinical signs. Blood was drawn for assessing oxidative stress markers as well as for parasitological examination and molecular analysis of the 18S rRNA gene of Babesia bigemina (B. bigemina). We performed a comparison of the levels of tumor necrosis factor-alpha (TNF-α) and interleukin-6 (IL-6) between B. bigemina-infected blood samples and non-infected blood samples used as negative controls. Babesia spp. infection increases hemolysis, which in turn increases oxidative stress marker levels and cell-mediated immune response.

Cyathocotylidae spp and motile aeromonads co-infections in farmed Nile tilapia (Oreochromis niloticus) causing mass mortality.

Motile aeromonads, and Cyathocotylidaespp.co-infections were identified in farmed Nile tilapia(Oreochromis niloticus) which suffering from mortalities. Moribund fish showed signs of septicemia, skin irritations, and respiratory distress. A total of 150 O. niloticus specimens showing signs of disease were collected from the affected earthmen ponds and examined. Bacteriological examination of fish samples revealed infections with motile aeromonads species. Phenotypic characteristics and phylogenetic analysis of gyrB gene sequences of aeromonads isolates identified them as Aeromonas hydrophila (12.6%), A.sobria (12.6%), and A. caviae (30.4%). Aeromonads strains harbored some virulence genes: Aer (78.62%); Hyl (60.86%); laf-A (52.17%); and Act (47.82%). The antibiogram of aeromonads showed high resistance against tetracycline (73.9%), and gentamycin (65.2%), while a high sensitivity was noticed to ciprofloxacin (82.6%),and trimethoprim/sulfamethoxazole (60.86%). Parasitological examination of fish revealed the presence of Cyathocotylidae spp. encysted metacercaria (EMC). High levels of interleukin 6 (IL-6) and cluster of differentiation 4 (CD4) were noticed in fish with parasitic and bacterial co-infection compared to those with a single infection or non-infected. Experimentally infected fish with Aeromonas spp. showed septicemic signs similar to that noticed in naturally infected tilapia with variable cumulative mortality. The study is one of the earlier reports identifying as Cyathocotylidae spp., and motile aeromonads co-infections, and their link with the exaggerated tilapia mortality which will be of value for incorporating these pathogens in the necessary management strategies to protect fish health.

The Biological Activity of Illicium verum (Star Anise) on Lernaea cyprinacea-Infested Carassius auratus (Goldfish): In Vivo Study.

Lernaea cyprinacea infestation is considered a serious economic problem in the fish market. An assessment to control this parasite is needed to manage this problem. The Illicium verum oil extract has considerable antioxidant activity and scavenges 96.22% of free radicals; the high antioxidant activity refers to the phenolic content presence. The extract contains minerals, especially K, fibers, and dry matter. So, the Illicium verum ingredients were tested against this copepod for in vitro and in vivo investigation with the assessment of the treatment trial using a scanning electron microscope and evaluating the change in different immunological genes in goldfish. Female parasitic L. cyprinacea worms were blackish and hairy. The in vitro study on L. cyprinacea adults using star anise revealed that the LC50 was 12.5 and 25 µg/mL for 2 and 1 h exposure periods, respectively. Interleukin (IL-1ß) and IL-6 were grossly upregulated in C. auratus-infested skin by L. cyprinacea after treatment by 1 week, then declined after 3 weeks. In contrast, TNF-α was 18 folds upregulated in the first week after treatment, with a decline after 3 weeks. In conclusion, star anise is recommended as a safe and economical agent for controlling L. cyprinacea infestation in fish.

Dactylogyrus extensus and Pseudomonas fluorescens dual infection in farmed common carp (Cyprinuscarpio).

Dactylogyrus extensus and Pseudomonas fluorescens are serious pathogens in Cyprinus carpio aquaculture causing severe impacts and substantial economic losses. During the early spring of 2021, abnormal mortalities were reported among farmed C. carpio. Moribund fish showed anorexia, respiratory distress, dermal ulcers, and septicemia. The water analysis revealed low dissolved oxygen (3.4 mg/L), and high un-ionized ammonia levels (0.65 mg/L). Seventy moribund C. carpio specimens were collected and subjected to parasitological and bacteriological examinations. The monogenetic trematode D. extensus was discovered in wet mounts from the gills of all the examined fish samples (100%). The identity of recovered parasites was confirmed by sequencing and alignment of the 28S rDNA gene. P. fluorescens was concurrently identified in the infested fish samples (58.5%) based on phenotypic characteristics using the API20 E. The identity of bacterial isolates was confirmed further by sequencing and alignment of 16S rRNA gene. The IL-1ß and MHCII were upregulated in infested fish in tandem with the severity of infections. P. fluorescens isolates displayed high resistance to most of the tested antibiotics. The study is one of the earlier reports on D. extensus and P. fluorescens co-infections in farmed C. carpio and highlights the need of effective control programs to protect fish health and minimize losses.

Immune Cell Reaction Associated with Coenurus cerebralis Infection in Sheep with Particular Reference to ELISA as a Diagnostic Tool.

Sturdy is a disease caused by Coenurus cerebralis (C. cerebralis) that typically affects the brain and spinal cord of sheep. So, this study aimed to detect the pathological, hematological and immunological changes caused by C. cerebralis in sheep. On examination, a total of 17 sheep out of 30 sheep (56.7%) from various regions in Egypt were found infected with C. cerebralis from May to August 2019. Each cyst was extracted from the sheep brain; in addition, tissue specimens were taken from the brain tissues for histopathological examination. The hematological profile was analyzed. Enzyme-Linked Immunosorbent Assay's (ELISA) specificity and sensitivity were evaluated using cystic fluid and protoscolices antigens (Ag). The cell-mediated immunity against the C. cerebralis cyst was also assessed via quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) to show alterations in mRNA expression of the Tumor Necrosis Factor-alpha (TNF-α) and gamma Interferon (IFN-γ) cytokines qRT-PCR. In histopathological sections, cerebral tissue showed an areolar cyst wall with many protoscolices attached to the tissue. The affected part showed prominent necrosis together with inflammatory cells' aggregation. Hyperplastic proliferation of the ependymal cells was a common finding. The infected sheep exhibited significantly lower total erythrocyte numbers (ER), hemoglobin levels (Hb), packed cell volume (PCV), platelet numbers (PN) and segmented cell numbers compared to apparently healthy sheep. Despite the sensitivity for the indirect ELISA being 100% for both of the Ags (fluid and scolex), the evaluation of ELISA specificity using the two antigen (Ag) preparations showed specificities of 46.2% and 38.5% for fluid and scolex Ag, respectively. Meanwhile accuracy ranged from 76.7% and 73.3% for the fluid and scolex Ags, respectively, that showed the priority was directed to the fluid to be used as an ideal sample type for ELISA. Levels of TNF-α and IFN-γ were significantly elevated in infected sheep compared to non-infected control ones. In conclusion, C. cerebralis is a serious disease infecting sheep in Egypt revealing economic losses. Although this investigation supports preliminary information about the prevalence, pathological and serological characterization of C. cerebralis, further sequencing and phylogenetic analysis is needed to understand better the T. multiceps epidemiology in ruminants and canines in Egypt.

Immunological status of some edible fishes exposed to parasitic infections in relation to heavy metals pollution.

In this study, six heavy metals (Pb, Fe, Cu, Ni, Cd, and Mn) have been measured in water, and muscles from mullet (Mugil cephalus), tilapia (Oreochromis niloticus), and African catfish (Clarias gariepinus) collected from Lake Manzal, Egypt. In addition, the existence of different encysted metacercariae in fish muscle with an evaluation of cell-mediated immune response in infected muscles was also investigated. Water samples generally contained less than the permissible level of heavy metals. The metal accumulation levels in muscle were: Pb > Ni > Cd > Cu > Fe > Mn. The levels of Pb and Ni in the muscles exceed the permissible limits, while the concentration of Mn varied significantly (p < 0.05) depending on fish species. Based on the estimated weekly intake in this study, the EWI values of these heavy metals are below the established Provisional Permissible Tolerable Weekly Intake. On the other hand, Prohemistomum vivax encysted metacercaria were found in the muscle of O. niloticus and C. gariepinus with the intensity of 1-10 cyst per 1 cm of muscle. While M. cephalus was found to be infected with Heterophyes heterophyes EMC. TNF- α1 was 10 folds upregulated in O. niloticus than in control fish. IL-1ß expression in O. niloticus was upregulated by 15 folds compared with the control one. By examining C. gariepinus, the MHC II gene expression was increased by 15-fold in comparison to the control group.

Morphomolecular characterization of Strongylus vulgaris isolated from donkeys with special references to histopathological study on the affected organs.

Equine gastrointestinal tract is infected with Strongylus vulgaris (S. vulgaris) which is highly pathogenic parasite for its harmful effect on cranial mesenteric artery during its migration. So, this study was applied for identification of S. vulgaris in donkeys ultramorphologically and molecularly. In addition to, detection of the pathological effect of larval stage of S. vulgaris on the mesenteric arterial system using histopathology and immunohistochemistry. During the period from September to December; 2019, 60 male and 20 female donkeys at the Giza Zoo was postmortem examined. S. vulgaris adults and larvae were collected from the large intestine and cranial mesenteric arteries (CMAs), respectively. Ultramorphological examination of the collected adults was done using scanning electron microscope (SEM). DNA was extracted from 5 larvae and 6 adults for further conventional PCR studies and sequencing of the internal transcriped spacer 2 (ITS2) gene. The ITS2 gene were amplified and showed bands at 148 base pair (bp). The ITS2 gene nucleotide sequences of all isolates were aligned using Basic Local Alignment Search Tool (BLAST). Histological sections of S. vulgaris affected mesenteric arteries exhibited the presence of the parasite larvae either in the lumen with thrombus formation or attached to the intima. Most of the detected inflammatory cell populations were CD68-positive cells. From these results, it can be concluded that the ribosomal spacers genes could be used as markers for Strongylus species identification in eggs collected from equine feces as a beneficial method of diagnosis. Also, it could be important in disease surveillance, improving preventive measures and developing an effective control strategy.