Number Of Parasites Research Articles

Silicon Fertilization Improves Sunflower Rhizosphere Microbial Community Structure and Reduces Parasitism by Orobanche cumana Wallr.

Sunflower broomrape (Orobanche cumana Wallr.) has severely restricted the development of the sunflower industry in China, and more efficient and convenient control methods are urgently needed. In this experiment, we investigated the effects of N, P and silica fertilizers on the parasitism rate of O. cumana, as well as on the yield of sunflower and native microbial communities in the field. Firstly, pot experiments were conducted to select the most effective fertilization method and to determine the physiological and biochemical indexes of sunflowers. Subsequently, field application studies were carried out to determine the physiological indexes, yield, O. cumana parasitism on sunflower, and the effect on the indigenous microbial community. The results demonstrate that compared with the CNP treatment (Control), the number of parasites under the N1P5 treatment significantly decreased by 66.15%. The exogenous application of silica can significantly reduce the number of O. cumana parasites. The treatments with N1P5 (N/P = 1:5) and available SiO2 content higher than 40 mg/kg (NS2, NS3, SF2 and SF3) significantly increased superoxide dismutase (SOD) activity and decreased malondialdehyde (MDA) content in sunflower leaves. In the field, fertilization significantly decreased the number of O. cumana parasites. The S treatment improved the native microbial community structure and enriched beneficial microorganisms, including Vicinamibacteria and Pyrinomonadaceae. Additionally, applying the S treatment significantly increased sunflower yield by 23.82% and crude protein content by 20.20%. In summary, the application of silicon fertilizer can effectively improve the host microbial community, reduce O. cumana parasitism and improve the yield and quality of sunflower.

Parasite infection in a cell population: role of the partitioning kernel.

We consider a cell population subject to a parasite infection. Cells divide at a constant rate and, at division, share the parasites they contain between their two daughter cells. The sharing may be asymmetric, and its law may depend on the number of parasites in the mother. Cells die at a rate which may depend on the number of parasites they carry, and are also killed when this number explodes. We study the survival of the cell population as well as the mean number of parasites in the cells, and focus on the role of the parasites partitioning kernel at division.

Immunomodulatory effect of hemozoin from Opisthorchis felineus and its participation in reducing allergic inflammation through activation of the inflammasome

Molecules of the excretory-secretory product arising as a result of co-evolution of a host and a parasite are able to inhibit the type 2 immune response, while activating the type 1 and the type 17 responses. The ability to alter the immune response can be used to inhibit inflammation in allergic diseases. In this regard, a search for helminth-associated molecules both with an immunomodulatory effect and immunogenicity and low toxicity is represented as a topical task. Hemozoin being a dark brown insoluble biocrystal is an excretory product of a number of hematophagous parasites (Schistosoma mansoni, Plasmodium falciparum and Opisthorchis felineus). This substance as a compound of parasitic origin with explicit immunomodulatory properties has prospects for deep research. Lots of relevant literature has been studied carefully before developing a concept about Opisthorchis felineus hemozoin and its unique properties. Thus, the current review presents an analysis of the accumulated data regarding the effect of Opisthorchis felineus trematode on the host immune system. Also the data on the immunomodulatory effect of hemozoin of various origins is analyzed. The current knowledge on the immune mechanisms of inflammasome activation and the possible role of hemozoin in reducing allergic inflammation through this mechanism is represented in this article. According to the systemized research results the excretory-secretory molecule of the liver fluke is a product of parasitic origin with an explicit immunomodulatory effect which is promising for prospective scientific study. Opisthorchis felineus extract increases the expression of T-regulatory cells and inhibits the Th2-immune response. Hemozoin produced by Opisthorchis felineus, like one produced by Plasmodium falciparum, may be involved in reducing the activity of allergic inflammation through activation of the inflammasome. Comprehension of the mechanism of how hemozoin interacts with the host immune system can be applied for correction of conditions associated with Th2-polarization of the immune response, which primarily include atopic diseases. Studying the mechanism of inflammation will help by the search for a biological target to create a vaccine to prevent the spread of atopic diseases, including bronchial asthma.

Modeling the impact of non-human host predation on the transmission of Chagas disease

In addition to the traditional transmission route via the biting-and-defecating process, non-human host predation of triatomines is recognized as another significant avenue for Chagas disease transmission. In this paper, we develop an eco-epidemiological model to investigate the impact of predation on the disease’s spread. Two critical thresholds, Rvp (the basic reproduction number of triatomines) and R0p (the basic reproduction number of the Chagas parasite), are derived to delineate the model’s dynamics. Through the construction of appropriate Lyapunov functions and the application of the Bendixson–Dulac theorem, the global asymptotic stabilities of the equilibria are fully established. The vector-free equilibrium E0 is globally stable when Rvp<1. E1, the disease-free equilibrium, is globally stable when Rvp>1 and R0p<1, while the endemic equilibrium E∗ is globally stable when both Rvp>1 and R0p>1. Numerical simulations highlight that the degree of host predation on triatomines, influenced by non-human hosts activities, can variably increase or decrease the Chagas disease transmission risk. Specifically, low or high levels of host predation can reduce R0p to below unity, while intermediate levels may increase the infected host populations, albeit with a reduction in R0p. These findings highlight the role played by non-human hosts and offer crucial insights for the prevention and control of Chagas disease.

Efficacy of Albizia malacophylla (A.Rich.) Walp. (Leguminosae) methanol (80%) leaf extract and solvent fractions against Plasmodium berghei-induced malaria in mice model

Ethnopharmacological relevanceNovel drugs are needed to address the issue of malarial infection resistance; natural items can be a different source of these medications. Albizia malacophylla (A. Rich.) Walp. (Leguminosae) is listed as one of the antimalarial medicinal plants in Ethiopian folk medicine. However, there are no reports regarding the biological activity or phytochemistry of the plant. Aim of the studyThus, this study aimed to evaluate the A. malacophylla crude extract and solvent fractions' in vivo antimalarial activity utilizing 4-day suppressive, preventative, and curative tests in mice infected with P. berghei. Materials and methodsThe parasite Plasmodium berghei, which causes rodent malaria, was used to infect healthy male Swiss Albino mice, weighing 23–28 g and aged 6–8 weeks. Solvent fractions such as methanol, water, and chloroform were given in addition to an 80% methanolic extract at 100, 200, and 400 mg/kg doses. A Conventional test such as parasitemia, survival time, body weight, temperature, and packed cell capacity were employed to ascertain factors such as the suppressive, curative, and preventive tests. ResultsEvery test substance dramatically reduced the number of parasites in every experiment. Crude extract (with the highest percentage suppression of 67.78%) performs better antimalarial effect than the methanol fraction, which is the most efficient solvent fraction with a percentage suppression of 55.74%. With a suppression value of 64.83% parasitemia level, the therapeutic effects of 80% methanolic crude extract were greater than its curative and preventative effects in a four-day suppressive test. The survival period (17 days) was longer with the hydroalcoholic crude extract dose of 400 mg/kg than with other doses of the materials under investigation. ConclusionsThe results of this investigation validate the antimalarial characteristics of A. malacophylla leaf extract. The crude extract prevented weight loss, a decline in temperature, and a reduction in PCV. The results demonstrate that the plant has a promising antimalarial effect against P. berghei, hence supporting the traditional use of the plant. Therefore, it could serve as a foundation for the development of new antimalarial drugs.

Circadian Regulation of Leishmania Parasite Internalisation in Macrophages and Downstream Cellular Events.

Leishmania spp. parasites use macrophages as a host cell during infection. As a result, macrophages have a dual role: clearing the parasite as well as acting as host cells. Recently, studies have shown that macrophages harbour circadian clocks, which affect many of their functions such as phagocytosis, receptor expression and cytokine release. Interestingly, Leishmania major infection in hosts was also shown to be under circadian control. Therefore, we decided to investigate what underlies the rhythms of L. major infection within macrophages. Using a culture model of infection of bone marrow-derived macrophages with L. major promastigotes, we show that the parasites are internalised into macrophages with a 24-h variation dependent on a functional circadian clock in the cells. This was associated with a variation in the number of parasites per macrophage. The cell surface expression of parasite receptors was not controlled by the cells' circadian clock. In contrast, the expression of the components of the endocytic pathway, EEA1 and LC3b, varied according to the time of infection. This was paralleled by variations in parasite-induced ROS production as well as cytokine tumour necrosis factor α. In summary, we have uncovered a time-dependent regulation of the internalisation of L. major promastigotes in macrophages, controlled by the circadian clock in these cells, as well as subsequent cellular events in the endocytic pathway, intracellular signalling and cytokine production.

Infectivity of an emerging fish parasite Gyrodactylus sprostonae in juvenile carp (Cyprinus carpio)

AbstractThe gill monogenean ectoparasite Gyrodactylus sprostonae is an emerging pathogen within recreational UK carp fisheries, and a major cause of mortality in adult carp. This gill infection has only been noted in adult carp and not in juveniles, and no reports of its fundamental infection dynamics exist. The current study compared the infective potential of G. sprostonae between adult and juvenile common carp (Cyprinus carpio) and quantified parasite numbers on the body surface and gills of infected juveniles at two temperatures (14 and 24°C). G. sprostonae was able to infect the body surface and the gills of juvenile carp, and temperature significantly impacted the duration of infection and number of parasites. Interestingly, however, all juveniles under both temperature treatments lost their infections after a maximum of 40 days, with no observed clinical signs of parasitaemia or mortalities. This study therefore indicates that G. sprostonae does not appear to be harmful to juvenile common carp, and we discuss why this infection only seems to impact prised adult carp in the UK.

Parasite infestation patterns differ between ticks and chigger mites on two rodent host species in Taiwan.

Parasites are typically concentrated on a few host individuals, and identifying the mechanisms underlying aggregated distribution can facilitate a more targeted control of parasites. We investigated the infestation patterns of hard ticks and chigger mites on two rodent species, the striped field mouse, Apodemus agrarius, and the lesser ricefield rat, Rattus losea, in Taiwan. We also explored abiotic and biotic factors that were important in explaining variation in the abundance of ticks and chiggers on rodent hosts. Ticks were more aggregated than chiggers on both rodent species. Factors important for the variation in parasitic loads, especially biotic factors, largely differed between ticks and chiggers. Variation partitioning analyses revealed that a larger proportion of variation in chiggers than in ticks can be explained, especially by abiotic factors. If, as proposed, the higher number of parasites in males is due to a larger range area or immunity being suppressed by testosterone, when A. agrarius males host more ticks, they are expected to also host more chiggers, given that chiggers adopt a similar host finding approach to that of ticks. Instead, the similar abundance of chiggers in male and female A. agrarius implies that a large home range or suppressed immunity does not predispose males to inevitably host more parasites. More variations were explained by abiotic than biotic factors, suggesting that controlling practices are more likely to be successful by focusing on factors related to the environment instead of host traits. Our study indicated that the extent of parasitism is rarely determined by a sole factor, but is an outcome of complex interactions among animal physiology, animal behavior, characteristics of parasites, and the environments.

Traditional and Novel Foods as Vectors for Human Parasitic Diseases

Consumption of food contaminated with parasites pose a significant threat to public health particularly in underprivileged communities with inadequate access to sanitation and food safety practices. Unlike bacterial and viral infections, parasitic infections often develop slowly and are reported cause chronic health issues. However, due to extended incubation time, it is difficult to determine the source of the infection. The type and number of parasites in food, the temperature at which food is prepared and stored, as well as a person's immune system, all of these contribute significantly to the onset of parasitic infection. This mini-review focuses on common parasitic infections, their emergence with traditional and novel foods, transmission mechanisms, epidemiological trends, and effective prevention and control measures. Understanding these aspects is crucial for developing strategies to reduce the impact of foodborne parasitic infections on public health, particularly in vulnerable populations.

Host guanylate binding proteins participate in parasite control during Leishmania infection

Abstract Cutaneous leishmaniasis (CL) is a debilitating neglected tropical disease causing lesions ranging from self-healing to permanent disfigurations. A predominant Th1 response relying on IFNγ production leads to parasite control during CL. Although IFNγ is mainly responsible for activating macrophages to produce NO leading to parasite control, IFNγ can activate other downstream pathways involved in cell autonomous immunity including the activation of guanylate binding proteins (GBPs), a class of interferon-inducible GTPases. GBPs play a role in host defense against some intracellular pathogens, but minimal work has been done to understand the role of GBPs during Leishmania infection. Utilizing RNA-Seq we found several GBPs are upregulated in lesions during L. major infection in mice. Single-cell RNA-Sequencing revealed macrophages as the main cell type expressing Gbps, including Gbp2, Gbp5, and Gbp7 during infection. Additionally, Gbp expression was not unique to L. major infection; both L. amazonensis and L. mexicana infection in vivo resulted in elevated Gbp expression. Preliminary in vitro experiments show macrophages from GBPChr3 KO mice harbor increased numbers of parasites compared to control macrophages with and without IFNγ treatment. Consistent with in vitro findings, infected GBPChr3 KO mice exhibit increased pathology compared to control mice. Together these data suggest GBPs participate in the defense against Leishmania parasites.

Humane Endpoints in Swiss Webster Mice Infected with Toxoplasma gondii RH Strain.

The highly virulent Toxoplasma gondii RH strain is maintained through successive passages in mice, but there is still a lack of studies that refine these procedures from a 3Rs perspective, where humanitarian ideals aim to minimize the stress, pain, or suffering of the animals used in the research without the loss of results. The aim of this study was to establish humane endpoints in Swiss Webster mice inoculated with the T. gondii RH strain. A total of 52 mice were infected with 5 × 106 tachyzoites/mL and monitored for periods of up to 5 days. The parameters body weight; hair condition; higher than normal body temperature; hypothermia; respiratory function; pain; soft stools or diarrhea; bloody diarrhea; tense, nervous, or in distress during handling; and ascites were recorded daily in score tables. The results showed that prominent piloerection, respiratory function, pain parameters, and ascites are important clinical signs to be used as a cut-off point for implementing euthanasia. The application of this refinement method helped to avoid animal suffering and pain without compromising the number of parasites recovered. We therefore suggest adopting these parameters in research protocols that require the maintenance of the T. gondii RH strain in murine models to avoid and reduce animal suffering.

Parasite load, rather than parasite presence, decreases upstream movement in Trinidadian guppies Poecilia reticulata.

Several factors influence whether an organism remains in its local habitat. Parasites can, for example, influence host movement by impacting their behavior, physiology, and morphology. In rivers, fish that swim efficiently against the current are able to maintain their position without being displaced downstream, a behavior referred to as positive rheotaxis. We hypothesized that both the presence and number of ectoparasites on a host would affect the ability of fish to avoid downstream displacement and thus prevent them from remaining in their habitat. We used the guppy-Gyrodactylus host-ectoparasite model to test whether parasite presence and parasite load had an effect on fish rheotaxis. We quantified rheotaxis of sham-infected and parasite-infected fish in a circular flow tank in the laboratory prior to infection and 5-6 days postinfection. Both parasite-infected and sham-infected individuals expressed similar levels of positive rheotaxis prior to infection and after infection. However, with increasing parasite numbers, guppies covered less distance in the upstream direction and spent more time in slower flow zones. These results suggest that higher numbers of Gyrodactylus ectoparasites negatively influence rheotactic movements. Further research is needed to understand the ecological and evolutionary implications of this ectoparasite on fish movement.

Body Size of Female Strepsipteran Parasites (Strepsiptera, Xenidae, Xenos) Depends on Several Key Factors in a Vespine Wasp (Hymenoptera, Vespidae, Vespa).

Parasite growth in hosts depends on their hosts' nutritional status. This study examined whether the body size of the strepsipteran parasite Xenos oxyodontes, which parasitizes the eusocial wasp Vespa analis, is affected by several key factors, including host body size. We collected V. analis using bait traps for three years in Niigata, Japan, and evaluated the number of male and female X. oxyodontes parasites throughout the seasons. A total of 185 female parasites were collected, and their cephalothorax widths were measured. The widths of female parasites did not statistically vary among seasons and were positively correlated with the head widths of female host wasps but negatively correlated with the number of parasites per host wasp. In addition, we examined whether the reproductive conditions of post-hibernation solitary queens affected the cephalothorax width of female parasites. The widths of the female parasites were greater when the queens had less-developed ovaries. These results suggested that nutrient availability by female parasites depends on the host wasp and competition with conspecific individuals.

Genetic infrapopulation sizes in blood parasites: a pilot quantification of the bottleneck in louse fly vectors

IntroductionBottleneck events are crucial for the strength of genetic drift, selection and speed of evolution. They are believed to play a particularly prominent role for parasitic infrapopulations, inhabiting single host individuals, which are often established by very few parasite individuals during transmission. In vector-borne pathogens, the bottlenecking effects can even be serialized through repeated filtering of parasitic stages at different tissues and organs of the vector. Using qPCR we aimed to quantify the number of potentially transmittable sporozoites of the hemosporidian blood parasite Haemoproteus columbae in the specialized vector louse flies Pseudolynchia canariensis which transmit these parasites between house pigeon hosts Columba livia.ResultsBased on qPCR measurements of organ-derived DNA of individual louse flies, we estimate that the midgut of these vectors contains on average 20 parasites, the hindgut and other intestines ca. 50 parasites and the salivary glands ca. 5 parasite cells. Nearly one third of all vector individuals appeared to lack parasite DNA, despite having only infected hosts as blood meal sources. The magnitude of parasite numbers in midgut and salivary glands tended to correlate positively.DiscussionOur results indicate, potential severe bottlenecking of parasite populations during individual transmission events and a probable effect of individual vector immunity on this variable. However, this may be partly alleviated by the coloniality of house pigeons, the frequency of louse flies and their daily feeding events in most populations, leading to repeated transmission opportunities, decreased quasi-vertical transmission between parents and offspring and probable panmixia of Haemoproteus columbae lineages. Many of these mechanisms might not apply in other host-vector systems. We propose several additional molecular and microscopical tools to improve the accuracy of estimating parasite population sizes in vectors and call for more estimations in different vector species to better understand the co-evolution between malaria-like blood parasites and their avian and insect hosts.

Proliferation in malaria parasites: How resource limitation can prevent evolution of greater virulence.

For parasites, robust proliferation within hosts is crucial for establishing the infection and creating opportunities for onward transmission. While faster proliferation enhances transmission rates, it is often assumed to curtail transmission duration by killing the host (virulence), a trade-off constraining parasite evolution. Yet in many diseases, including malaria, the preponderance of infections with mild or absent symptoms suggests that host mortality is not a sufficient constraint, raising the question of what restrains evolution toward faster proliferation. In malaria infections, the maximum rate of proliferation is determined by the burst size, the number of daughter parasites produced per infected red blood cell. Larger burst sizes should expand the pool of infected red blood cells that can be used to produce the specialized transmission forms needed to infect mosquitoes. We use a within-host model parameterized for rodent malaria parasites (Plasmodium chabaudi) to project the transmission consequences of burst size, focusing on initial acute infection where resource limitation and risk of host mortality are greatest. We find that resource limitation restricts evolution toward higher burst sizes below the level predicted by host mortality alone. Our results suggest resource limitation could represent a more general constraint than virulence-transmission trade-offs, preventing evolution towards faster proliferation.

Heritability and predictive ability for the heterobothriosis resistance and growth performance in the tiger pufferfish Takifugu rubripes fed standard or low fishmeal diets

Heterobothriosis resistance and high growth performance are major concerns in the tiger pufferfish (Takifugu rubripes) farming. Our previous small-scale study suggested the feasibility of genomic selection (GS) for these traits but also identified an undesired genetic correlation between them, which could hamper simultaneous genetic improvement. Here, we sought to validate these initial findings through larger samples and crosses and also explore the potential of GS for the individuals fed a normal fishmeal diet and a low fishmeal (LFM) diet. We produced three populations: one was fed a normal diet (PopFM: 1100 individuals) and two were fed an LFM diet (PopLFM1: 993 individuals; PopLFM2: 1017 individuals); all three populations were artificially infected with Heterobothrium okamotoi, a monogenean parasite causing heterobothriosis. We recorded standard lengths of the fish after artificial infection (SLEAI) and the number of parasites on the gill cavity wall (HC) and genotyped genome-wide single nucleotide polymorphisms (SNPs) using genotyping by random amplicon sequencing, direct (GRAS-Di) technology for each sample: PopFM, 12 K SNPs; PopLFM1, 19 K SNPs; PopLFM2, 21 K SNPs. Heritability and prediction ability for each trait were estimated for each population using genomic best linear unbiased prediction (GBLUP), Bayes C, and Bayesian ridge regression methods. SNP effects on each trait were estimated by Bayes C, Bayesian ridge regression, and genome-wide association analyses (GWAS) using the same data sets. We observed moderate to high levels of heritability for HC (0.16–0.57) and SLEAI (0.50–0.77), with predictive ability of 0.25–0.55 for HC and of 0.51–0.73 for SLEAI. These values were slightly larger in LFM diet groups. As reported previously, a weak undesired genetic correlation was observed between the traits, and the correlation was more pronounced in the LFM groups. In conclusion, our results indicate that genetic gain in growth and parasite resistance traits can be expected for the tiger pufferfish through GS, especially for individuals reared on an LFM diet. However, close attention should be paid to the extent of the undesirable genetic correlation between the two traits that may be amplified in the populations fed an LFM diet.

Searching for common patterns in parasite ecology: species and host contributions to beta-diversity in helminths of South African ungulates and fleas of South American rodents

We searched for common patterns in parasite ecology by investigating species and host contributions to the beta-diversity of infracommunities (=assemblages of parasites harboured by a host individual) in helminths of three species of South African ungulates and fleas of 11 species of South American rodents, assuming that a comparison of patterns in distinctly different parasites and hosts would allow us to judge the generality or, at least, commonness of these patterns. We used data on species’ composition and numbers of parasites and asked whether (i) parasite species’ attributes (life cycle, transmission mode, and host specificity in helminths; possession of sclerotized combs, microhabitat preference, and host specificity in fleas) or their population structure (mean abundance and/or prevalence) and (ii) host characteristics (sex and age) affect parasite and host species’ contributions to parasite beta-diversity (SCBD and HCBD, respectively). We found that parasite species’ morphological and ecological attributes were mostly not associated with their SCBD. In contrast, parasite SCBD, in both ungulates and rodents, significantly increased with either parasite mean abundance or prevalence or both. The effect of host characteristics on HCBD was detected in a few hosts only. In general, parasite infracommunities’ beta-diversity appeared to be driven by variation in parasite species rather than the uniqueness of the assemblages harboured by individual hosts. We conclude that some ecological patterns (such as the relationships between SCBD and parasite abundance/prevalence) appear to be common and do not differ between different host-parasite associations in different geographic regions, whereas other patterns (the relationships between SCBD and parasite species’ attributes) are contingent and depend on parasite and host identities.

Parasites Infestation on Cultured Barramundi (Lates calcarifer) and the Impact of Fish Health

Barramundi Lates calcarifer is one of the leading marine aquaculture commodities in Indonesia, therefore fish health should be observed. This study was conducted to determine the type and number of parasites present in barramundi, the prevalence, mean intensity and mean abundance of parasite and the number of leukocytes in each individual, based on the level of infestation. This study used a quantitative descriptive method, using a total of 30 fish with two different sizes of host of ± 20 cm (large) and ±5 cm (small) each as many as 15 individuals. The results showed that size of host samples influenced the number of parasites infested with the prevalence of 40%, while ectoparasite 20%. This may due to differences in the living environment as well as the larger host provides more space to the parasites. The ectoparasites found in barramundi, namely Trichodina sp, Cryptocaryon sp, Benedenia sp, Diplectanum sp and endoparasites, namely Camallanus sp. Ectoparasites Trichodina sp. has the highest mean intensity of 20%. The highest mean abundance on large fish was 3.2 ind/fish on ectoparasite and endoparasites was 0.07 ind/fish. The lowest leukocytes were 179.82 103/μl (19.6 cm) and the highest in sample number three was 218 103/μl (20 cm), all exceeded the normal amount of leucocytes cells for fish was uninfected.

Endo-Parasites of some Fresh Water Fish in Zobe Dam, Dutsin-Ma, Kastina State

Parasites of fish, either external or internal constitute one of the major problems to fish health and also a great concern; since they often cause disease conditions in fish which can also be transferred to man, The study is aimed to identify the endo-parasites of some fresh water fish in Zobe dam Dutsin-Ma, Kastina State. A total of 180 fish were collected from 3 different fish species. The collected Fish samples were transported in a cool bucket containing ice flex to the Biology laboratory. The fishes were weighed and placed on a dissecting tray for proper dissection in order to reveal the internal organs. They were centrifuge and the content was place on a slide for microscopic examination. The total number of the parasite based on class were 37 and varies according to the fish species. Oreochromis. niloticus and Clarias. garienpinus had the highest number of parasites with a total of 15 and 12 respectively while Bargus bayard had the lowest parasite load with 10 parasites. The highest mean fish weight recorded in this study is 0.21kg with percentage infection of 40%. The sizes of the fish species are all within the range of 9–38cm, the longest fish has size range of 1 to 38 with percentage infection of 40%. This result therefore suggests that there were various fish parasites from fish sample collected from Zobe dam and fish should be properly cooked or smoked before consumption to avoid health risk due to some these parasites.

Correlation between the Fasciola hepatica infection rate (number of parasites in the liver parenchyma) and the antibody titration, detected by ELISA assay.

This study aimed to demonstrate the existence of a possible correlation between the level of liver fluke infection in cattle caused by Fasciola hepatica and the titers of anti-parasite antibodies in the blood. 113 blood samples were taken from non-dewormed pasture cattle in the communal slaughterhouse of the Jijel city in order to determine the serological titration of anti-fluke antibodies by the ELISA method. After slaughtering the animals studied, a count of parasites present in the inspected livers was carried out in order to assess the level of parasitic infection. The prevalence of bovine fasciolosis (due to Fasciola hepatica) based on counting the number of flukes in the inspected livers was around 61.06%, while the seroprevalence obtained is 55.75%. The sensitivity and specificity of the ELISA test used in this study were, respectively, 91.3% and 100%. A very strong correlation (r = 0.93 to p < 0.0001) was statistically demonstrated between the antibody titers and the number of flukes in the inspected livers. According to the results of this study, there is a strong statistical correlation between serum antibody titers and the number of flukes present in the liver (the higher the number of parasites in the liver, the higher the level of anti-flukes antibodies in the blood).