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Abstract Due to differences in their feeding behavior, sheep and goats are often assumed to respond differently to helminth infections. The present study compared Haemonchus contortus infection profile between sheep and goats under the same experimental setting. Experimental infection was conducted using a randomized block design in four groups of intact sheep (InfSH and ConSH) and goats (InfG, and ConG). Groups InfSH and InfG (N = 7 each) received 10,000L3 of H. contortus whereas the control groups ConSH and ConG (N = 7 each) remained uninfected. Faecal egg counts and PCV were measured from Day 0 to day 56 post infection (PI). On day 56 PI, animals were humanely slaughtered and abomasal contents were recovered to measure worm burden, worm length and in utero egg count. The findings show that: (1) Haemonchus infected animals showed an increase in FEC starting from day 21 PI, (2) progressive reduction in PCV was registered from day 7 PI and continued to the end of the experiment while this remained at pre-infection levels in control groups, (3) FEC was much higher (P

Due to differences in their feeding behavior, sheep and goats are often assumed to respond differently to helminth infections. The present study compared Haemonchus contortus infection profile between sheep and goats under the same experimental setting. Experimental infection was conducted using a randomized block design in four groups of intact sheep (InfSH and ConSH) and goats (InfG, and ConG). Groups InfSH and InfG (N = 7 each) received 10,000L3 of H. contortus whereas the control groups ConSH and ConG (N = 7 each) remained uninfected. Faecal egg counts and PCV were measured from Day 0 to day 56 post infection (PI). On day 56 PI, animals were humanely slaughtered and abomasal contents were recovered to measure worm burden, worm length and in utero egg count. The findings show that: (1) Haemonchus infected animals showed an increase in FEC starting from day 21 PI, (2) progressive reduction in PCV was registered from day 7 PI and continued to the end of the experiment while this remained at pre-infection levels in control groups, (3) FEC was much higher (P < 0.001) and PCV was significantly lower (P < 0.05) in infected goats than in infected sheep, (4) at necropsy, total worm burden with worm establishment rates of 63% and 28.87% were registered respectively for infected goats and sheep with significant difference (P < 0.05), (5) Female worms were significantly longer (P < 0.05) in InfG (22.8(± 1.2) compared to InfSH (20.5 ± 0.67 mm) while (6) Mean worm fecundity was 974.8 ± 239.4 and 1162.5 ± 89.4 respectively for groups InfSH and InfG with no significant difference (P = 0.07), and (7) Parasite traits such as worm burden, FEC and female worm length were well correlated in sheep whereas few such patterns were observed in goats. In conclusion, under the same experimental infection, Arsi-Bale goats are more susceptible to H. contortus infection than Arsi-Bale sheep and hence deserve special attention when they are forced to live on grazing rather than browsing. [ABSTRACT FROM AUTHOR]

Background: Haemonchus contortus (H. contortus), a nematode with global prevalence, poses a major threat to the gastrointestinal health of sheep and goats. In an effort to combat this parasite, a nanovaccine was created using a recombinant ADP-ribosylation factor 1 (ARF1) antigen encapsulated within poly lactic-co-glycolic acid (PLGA). This study aimed to assess the effectiveness of this nanovaccine in providing protection against H. contortus infection. Methods: Fifteen goats were randomly divided into three groups. The experimental group received two doses of the PLGA encapsulated rHcARF1 (rHcARF1-PLGA) nanovaccine on days 0 and 14. Fourteen days after the second immunization, both the experimental and positive control groups were challenged with 8000 infective larvae (L3) of H. contortus, while the negative control group remained unvaccinated and unchallenged. At the end of the experiment on the 63rd day, all animals were humanly euthanized. Results: The results showed that the experimental group had significantly higher levels of sera IgG, IgA, and IgE antibodies, as well as increased concentrations of cytokines, such as IL-4, IL-9, IL-17, and TGF-β, compared to the negative control group after immunization. Following the L3 challenge, the experimental group exhibited a 47.5% reduction in mean eggs per gram of feces (EPG) and a 55.7% reduction in worm burden as compared to the positive control group. Conclusions: These findings indicate that the nanovaccine expressing rHcARF1 offers significant protective efficacy against H. contortus infection in goats. The results also suggest the need for more precise optimization of the antigen dose or a reassessment of the vaccination regimen. Additionally, the small sample size limits the statistical rigor and the broader applicability of the findings. [ABSTRACT FROM AUTHOR]

Background: Haemonchus contortus (H. contortus), a nematode with global prevalence, poses a major threat to the gastrointestinal health of sheep and goats. In an effort to combat this parasite, a nanovaccine was created using a recombinant ADP-ribosylation factor 1 (ARF1) antigen encapsulated within poly lactic-co-glycolic acid (PLGA). This study aimed to assess the effectiveness of this nanovaccine in providing protection against H. contortus infection. Methods: Fifteen goats were randomly divided into three groups. The experimental group received two doses of the PLGA encapsulated rHcARF1 (rHcARF1-PLGA) nanovaccine on days 0 and 14. Fourteen days after the second immunization, both the experimental and positive control groups were challenged with 8000 infective larvae (L3) of H. contortus, while the negative control group remained unvaccinated and unchallenged. At the end of the experiment on the 63rd day, all animals were humanly euthanized. Results: The results showed that the experimental group had significantly higher levels of sera IgG, IgA, and IgE antibodies, as well as increased concentrations of cytokines, such as IL-4, IL-9, IL-17, and TGF-β, compared to the negative control group after immunization. Following the L3 challenge, the experimental group exhibited a 47.5% reduction in mean eggs per gram of feces (EPG) and a 55.7% reduction in worm burden as compared to the positive control group. Conclusions: These findings indicate that the nanovaccine expressing rHcARF1 offers significant protective efficacy against H. contortus infection in goats. The results also suggest the need for more precise optimization of the antigen dose or a reassessment of the vaccination regimen. Additionally, the small sample size limits the statistical rigor and the broader applicability of the findings.

Haemonchus contortus is the most prevalent and pathogenic gastrointestinal nematodes (GINs) in ruminants causing extensive economic losses. It is essential to estimate the efficacy of common commercially available anthelmintics against Haemonchus contortus parasite. Here, we standardized an ex-vivo culture platform for H. contortus and evaluated the efficacy of commonly used anthelmintics namely, albendazole (ABZ), levamisole (LVM), ivermectin (IVM), closantel (CLS) and rafoxanide (RFX). Adult worms were collected from abomasa of slaughtered animals, cultured in MEM, DMEM, M199 or RPMI with or without 20% FBS for up to 72 h. Cultured worms were incubated with ABZ, LVM, IVM, RFX or CLS in DMEM supplemented with 20% FBS at different concentrations (0.5–50 µg/ml) in triplicates and examined at 0, 3, 6, 12, 24, 36 and 48 h post treatment. Of the culture conditions, DMEM supplemented with 20% FBS supported the survival of H. contortus for (P < 0.001) longer period of time which was used in the evaluation of anthelmintics. The efficacy of CLS and RFX were significantly (P < 0.001) higher than other drugs and 100% mortality was observed at 2 µg/ml of CLS and RFX within 12 h post treatment. However, ABZ, LVM, and IVM showed significant effect at the concentration of 50 µg/ml with 48, 36, and 24 h, respectively. Morphological changes included severe cuticle disruption around the buccal cavity, posterior region and vulva as well as loss of cuticle structure integrity coupled with expulsion and fragmentation of digestive components of parasites when treated with 50 µg/ml of ABZ, LVM, and IVM and 2 µg/ml of RFX and CLS. Collectively, DMEM supplemented with 20% FBS can be used as ex-vivo culture platform for maintenance of H. contortus, and RFX and CLS can be used as the promising drugs for the prevention, control and treatment of H. contortus infections. [ABSTRACT FROM AUTHOR]

Abstract Background The parasites causes localized and generalized infections to the host depends on the parasite attachment organs, depth of penetration, site of location and worm burdens. Methods The experimental study was done between December, 2019 and April, 2020 in the fly-proof experimental animal facility located in the premise of the College of Veterinary Medicine and Agriculture at Bishoftu, Ethiopia. A total of 14 male goat (G1 and G2) and 14 male sheep (G3 and G4) were allotted in to four equal groups. Single dose of 10,000 of infective larvae of Haemonchus contortus (L3) was orally administered to each animal in G1 and G3. Parameters such as body weight, PCV, haemoglobin, worm count, serum total protein, serum albumin, alkaline phosphatase and aspartate aminotransferase were measured. Moreover, histopathological sections were stained and examined for general changes as well as for changes in specific cells such as tissue eosinophilia and parietal cell population. Results The findings show that 1) All infected sheep and goats developed the infection with higher mean worm burden in goats (5590) than sheep (2887) and the difference was significant (P

Abstract Unlike the successful immunization of native H. contortus antigens that contributed to the realization of the first commercial vaccine Barbervax, not many studies revealed the encouraging protective efficacies of recombinant H. contortus antigens in laboratory trials or under field conditions. In our preliminary study, H. contortus α/β-hydrolase domain protein (HcABHD) was demonstrated to be an immunomodulatory excretory–secretory (ES) protein that interacts with goat T cells. We herein evaluated the protective capacities of two HcABHD preparations, recombinant HcABHD (rHcABHD) antigen and anti-rHcABHD IgG, against H. contortus challenge via active and passive immunization trials, respectively. Parasitological parameter, antibody responses, hematological pathology and cytokine profiling in unchallenged and challenged goats were monitored and determined throughout both trials. Subcutaneous administration of rHcABHD with Freund adjuvants elicited protective immune responses in challenged goats, diminishing cumulative fecal egg counts (FEC) and total worm burden by 54.0% and 74.2%, respectively, whereas passive immunization with anti-rHcABHD IgG conferred substantial protection to challenged goats by generating a 51.5% reduction of cumulative FEC and a 73.8% reduction of total worm burden. Additionally, comparable changes of mucosal IgA levels, circulating IgG levels, hemoglobin levels, and serum interleukin (IL)-4 and IL-17A levels were observed in rHcABHD protein/anti-rHcABHD IgG immunized goats in both trials. Taken together, the recombinant version of HcABHD might have further application under field conditions in protecting goats against H. contortus infection, and the integrated immunological pipeline of ES antigen identification, screening and characterization may provide new clues for further development of recombinant subunit vaccines to control H. contortus.

Abstract Background Gastrointestinal nematodes could release excretory-secretory (ES) proteins into the host environment to ensure their survival. These ES proteins act as immunomodulators to suppress or subvert the host immune response via the impairment of immune cell functions, especially in chronic infections. In our preliminary study, Haemonchus contortus adhesion-regulating molecule 1 (HcADRM1) was identified from H. contortus ES proteins (HcESPs) that interacted with host T cells via liquid chromatography-tandem mass spectrometry analysis. However, little is known about HcADRM1 as an ES protein which may play a pivotal role at the parasite-host interface. Methods Based on bioinformatics approaches, multiple amino acid sequence alignment was conducted and the evolutionary relationship of HcADRM1 with ADRM1 orthologues was extrapolated. Employing RT-qPCR and immunohistochemistry assays, temporal transcriptional and spatial expression profiles of HcADRM1 were investigated. Using immunostaining approaches integrated with immunological bioassays, the immunomodulatory potentials of HcADRM1 on goat T cells were assessed. Results We hereby demonstrated that HcADRM1 with immunodiagnostic utility was a mammalian ADRM1 orthologue abundantly expressed at all developmental stages of H. contortus. Given the implications of ADRM1 proteins in cell growth, survival and development, we further investigated the immunomodulatory property of HcADRM1 as an individual ES protein acting at the parasite-host interface. The rHcADRM1 stimuli notably suppressed T cell viability, promoted intrinsic and extrinsic T cell apoptosis, inhibited T cell proliferation and induced cell cycle arrest at G1 phase. Simultaneously, rHcADRM1 stimuli exerted critical controls on T cell cytokine secretion profiles, predominantly by restraining the secretions of interleukin (IL)-4, IL-10 and interferon-gamma. Conclusions Importantly, HcADRM1 protein may have prophylactic potential for anti-H. contortus vaccine development. Together, these findings may contribute to the clarification of molecular and immunomodulatory traits of ES proteins, as well as improvement of our understanding of parasite immune evasion mechanism in H. contortus-host biology.

The prevention, treatment and control of Haemonchus contortus have been increasingly problematic due to its widespread occurrence and anthelmintic resistance. There are very few descriptions of recombinant antigens being protective for H. contortus, despite the success of various native antigen preparations, including Barbervax. We recently identified an H. contortus excretory–secretory antigen, H. contortus adhesion-regulating molecule 1 (HcADRM1), that served as an immunomodulator to impair host T-cell functions. Given the prophylactic potential of HcADRM1 protein as a vaccine candidate, we hereby assessed the efficacies of HcADRM1 preparations against H. contortus infection. Parasitological and immunological parameters were evaluated throughout all time points of the trials, including fecal egg counts (FEC), abomasal worm burdens, complete blood counts, cytokine production profiles and antibody responses. Active vaccination with recombinant HcADRM1 (rHcADRM1) protein induced protective immunity in inoculated goats, resulting in reductions of 48.9 and 58.6% in cumulative FEC and worm burdens. Simultaneously, passive administration of anti-HcADRM1 antibodies generated encouraging levels of protection with 46.7 and 56.2% reductions in cumulative FEC and worm burdens in challenged goats. In addition, HcADRM1 preparations-immunized goats showed significant differences in mucosal and serum antigen-specific immunoglobulin G (IgG) levels, total mucosal IgA levels, haemoglobin values and circulating interferon-γ, interleukin (IL)-4 and IL-17A production compared to control goats in both trials. The preliminary data of these laboratory trials validated the immunoprophylactic effects of rHcADRM1 protein. It can be pursued as a potential vaccine antigen to develop an effective recombinant subunit vaccine against H. contortus under field conditions. [ABSTRACT FROM AUTHOR]

The development of host resistance to anthelmintics and the increasing cost of commercial anthelmintics have encouraged the need for the in vitro anthelmintic evaluation of crude extract and fractions of Hymenodictyon pachyanta plant as alternative drugs against Haemonchus contortus. H. contortus is one of the most prevalent and highly pathogenic parasitic nematodes in small ruminant farming globally. H. pachyanta stem bark is a prospective plant used by the local and indigenous farmers of Nsukka, Enugu state, Nigeria. The stem bark of H. pachyanta were collected, dried, pulverized and extracted with 80 % methanol. The purpose of this study was to investigate the in vitro anthelmintic effects of these crude extract and fractions against H. contortus in sheep and goats. The two extracts (crude and fractions) of H. pachyanta were tested by the egg hatch assay (EHA) and the larval development inhibition assays (LDIA) and to compared the results with albendazole (as the positive control). The concentrations for the crude extract and albendazole used for this study were 0.78, 1.56, 3.125, 6.25 and 12.5 mg.ml−1. The results demonstrated that the crude extracts, fractions and albendazole all at the concentration doses of 12.5 mg.ml−1 produced 100 % inhibition of egg hatching and larval development. Statistically, there was no significant difference (P > 0.05) in the mean percentage inhibition of egg hatching and larval development inhibition of the crude extracts and fractions when compared with albendazole. However, a significant difference (P < 0.05) was observed with n-butanol fraction which inhibited 96.17 % of egg hatchability. All of the extracts and albendazole showed ovicidal and larvicidal effects and were able to induce over 50 % of the egg hatching and mortality of larvae at the concentration ranges of 0.78—12.5 mg.ml−1. The results obtained from our study suggest that H. pachyanta had ovicidal and larvicidal activity against H. contortus and that the bioactive plants compounds responsible for this effect could be attributed to the presence of tannins, alkaloids and the saponins contained in the crude extracts.

Objective: This study aimed to explore the phytochemical constituents and anthelmintic activities of four Cassia spp. leaves against Haemonchus contortus. Materials and Methods: The extracts were prepared from four species of Cassia spp. (C. siamea, C. fistula, C. surattensis, and C. spectabilis). Phytochemical screening of the extract was done based on the Harborne method. Evaluation of the anthelmintic activities against H. contortus was done in vitro using infective larvae (L3) migration inhibition assay (LMIA). Measurement of larvae migrating was conducted through a nylon filter with a pore size of 20 μm. The doses of Cassia spp. extract implemented were 25, 50, 100, and 200 mg/ml. Results: Tannins, alkaloids, phenol hydroquinone, flavonoids, steroids, triterpenoids, and sapo¬nins were present in all the extracts, whereas alkaloids were absent in C. fistula. No triterpenoids were found in C. surattensis and C. spectabilis. Movement of H. contortus larvae was significantly inhibited after exposure to Cassia extracts at various dosage levels (p < 0.05). The test results using LMIA on L3 H. contortus showed the lowest inhibition in the negative control. Among the species of Cassia, the C. surattensis (at 200 mg/ml) showed the highest (p < 0.05) inhibition level on the larvae. The latter result corresponded to the effect of albendazole. Conclusion: Compared to other Cassia spp., C. surattensis exhibited the highest inhibition against L3 H. contortus. However, the inhibition effect of C. surattensis was still lower as compared to albendazole. [J Adv Vet Anim Res 2019; 6(2.000): 236-240]

The α/β-hydrolase domain (ABHD) proteins belonging to α/β-hydrolase (ABH) superfamily are ubiquitously distributed throughout all the organisms, and their functional roles have been implicated in energy metabolism, cell signaling, growth and development. In our preliminary work, we identified a novel ABHD protein derived from Haemonchus contortus excretory-secretory (ES) proteins (HcESPs) that interacted with host T cells. Here, we demonstrated that H. contortus ABHD (HcABHD) protein, expressed in all life-cycle stages of H. contortus, is a mammalian ABHD17 homolog with immunodiagnostic utility and lipase activity. Given its catalytic activities and immunomodulatory potentials, we further investigated the functional diversity of HcABHD as an individual ES protein in parasite-host interactions. HcABHD protein may serve as depalmitoylase or thioesterase to suppress cell viability, inhibit cell proliferation, induce intrinsic and extrinsic T cell apoptosis, and cause cell cycle arrested at G1 phase. Moreover, recombinant HcABHD stimuli exerted critical controls on T cell cytokine production profiles, predominantly by inhibiting the secretions of interleukin (IL)-4, interferon-gamma (IFN-γ) and transforming growth factor-beta (TGF-β) 1, and promoting IL-10 production. As the immunomodulator acting at the parasite-host interface, HcABHD protein may have potential applications for the vaccine development of therapeutic intervention. Together, these findings may help illuminate the molecular and particularly immunomodulatory aspects of ES proteins and contribute to an enhanced understanding of parasite immune evasion in H. contortus-host biology.

Unlike the successful immunization of native H. contortus antigens that contributed to the realization of the first commercial vaccine Barbervax, not many studies revealed the encouraging protective efficacies of recombinant H. contortus antigens in laboratory trials or under field conditions. In our preliminary study, H. contortus α/β-hydrolase domain protein (HcABHD) was demonstrated to be an immunomodulatory excretory–secretory (ES) protein that interacts with goat T cells. We herein evaluated the protective capacities of two HcABHD preparations, recombinant HcABHD (rHcABHD) antigen and anti-rHcABHD IgG, against H. contortus challenge via active and passive immunization trials, respectively. Parasitological parameter, antibody responses, hematological pathology and cytokine profiling in unchallenged and challenged goats were monitored and determined throughout both trials. Subcutaneous administration of rHcABHD with Freund adjuvants elicited protective immune responses in challenged goats, diminishing cumulative fecal egg counts (FEC) and total worm burden by 54.0% and 74.2%, respectively, whereas passive immunization with anti-rHcABHD IgG conferred substantial protection to challenged goats by generating a 51.5% reduction of cumulative FEC and a 73.8% reduction of total worm burden. Additionally, comparable changes of mucosal IgA levels, circulating IgG levels, hemoglobin levels, and serum interleukin (IL)-4 and IL-17A levels were observed in rHcABHD protein/anti-rHcABHD IgG immunized goats in both trials. Taken together, the recombinant version of HcABHD might have further application under field conditions in protecting goats against H. contortus infection, and the integrated immunological pipeline of ES antigen identification, screening and characterization may provide new clues for further development of recombinant subunit vaccines to control H. contortus. [ABSTRACT FROM AUTHOR]

Helminths have been a serious trouble for the farmers due to their adverse effects on small ruminant production. Hemonchus contortus (H. contortus) and Fasciola hepatica (F. hepatica) are highly pathogenic and pose serious threat in co-existence. Because of increasing threat of anthelmintic resistance, alternative methods are being investigated and the herbal remedies stand the most prominent due to their efficacy and availability. Anthelmintic activity of the herbal mixture was evaluated in goats. Adult goats were selected at Livestock Production and Research Centre (LPRI) Bahadarnagar, Okara and were examined for helminth eggs in their feces. Twenty-four goats having almost similar egg per gram (EPG) of feces values of H. contortus and F. hepatica were selected and allocated to four groups of equal size. Herbal mixture was administered at dose rate of 1400, 1200 and 1000 mg/kg to each member of groups G1, G2 and G3, respectively on day 0, 7, 14 and 21 of the trials, while group G4 served as negative control receiving no medicine/herbal mixture. Trials continued for 30 days and data about EPG, fecal egg count reduction, complete blood count and serum biochemistry were collected before administration of herbal mixture at day 15 and day 30 of trial while animals were weighed before initiation of trial (day 0) and at the end of trial (day 30). All treatments showed a significant reduction in fecal egg count as compared to control group. Maximum fecal egg count reduction was observed in animals of group G1, which is 91.35% for H. contortus and 82.35% for F. hepatica. There was a slight increase in weight gain ratio of the treated animals in respective decreasing order with G1 having highest weight gain. An increase in erythrocyte count, pack cell volume and hemoglobin concentration was recorded while non-significant effect was observed on serum parameters. The results of this trial suggested that herbal dewormer is effective and can be an option for integrated management strategies for nematodes and trematodes control in the goats. [ABSTRACT FROM AUTHOR]

The α/β-hydrolase domain (ABHD) proteins belonging to α/β-hydrolase (ABH) superfamily are ubiquitously distributed throughout all the organisms, and their functional roles have been implicated in energy metabolism, cell signaling, growth and development. In our preliminary work, we identified a novel ABHD protein derived from Haemonchus contortus excretory-secretory (ES) proteins (HcESPs) that interacted with host T cells. Here, we demonstrated that H. contortus ABHD (HcABHD) protein, expressed in all life-cycle stages of H. contortus , is a mammalian ABHD17 homolog with immunodiagnostic utility and lipase activity. Given its catalytic activities and immunomodulatory potentials, we further investigated the functional diversity of HcABHD as an individual ES protein in parasite-host interactions. HcABHD protein may serve as depalmitoylase or thioesterase to suppress cell viability, inhibit cell proliferation, induce intrinsic and extrinsic T cell apoptosis, and cause cell cycle arrested at G1 phase. Moreover, recombinant HcABHD stimuli exerted critical controls on T cell cytokine production profiles, predominantly by inhibiting the secretions of interleukin (IL)-4, interferon-gamma (IFN-γ) and transforming growth factor-beta (TGF-β) 1, and promoting IL-10 production. As the immunomodulator acting at the parasite-host interface, HcABHD protein may have potential applications for the vaccine development of therapeutic intervention. Together, these findings may help illuminate the molecular and particularly immunomodulatory aspects of ES proteins and contribute to an enhanced understanding of parasite immune evasion in H. contortus -host biology. [ABSTRACT FROM AUTHOR]

Haemonchosis is a parasitic disease of small ruminants that adversely affects livestock production. Haemonchus contortus is one of the most prevalent nematode parasites that infect the abomasum of small ruminants. This parasite reduces milk production, overall growth and sometimes causes the death of the infected animals. The evaluation of the biocontrol potential of some abomasum bacterial isolates against H. contortus is investigated in this study. Out of which, three isolates—Comamonas testosteroni, Comamonas jiangduensis, Pseudomonas weihenstephanesis—show significant effect against the nematode L3, adult, and egg hatch inhibition assays. Various concentrations of metabolites from these bacteria are prepared and applied in different treatments compared with control. In the case of adult mortality assay, 50% metabolites of C. testosteroni and P. weihenstephanesis show 46% adult mortality, whereas C. jiangduensis shows 40% mortality. It is observed that decreasing the concentration of bacterial metabolite, lowers nematode mortality. The minimum nematode mortality rate is recorded at the lowest filtrates concentration of all the bacterial isolates. The same trend is observed in egg hatch inhibition assay, where the higher concentration of bacterial culture filtrates shows 100% inhibition of H. contortus egg. It is concluded that the effect of bacterial culture filtrates against H. contortus is dose-dependent for their activity against nematode L3, adult, and inhibition of egg hatchment.

The inhibitory effects of Piliostigma thoningii pod extract and fractions were carried out on Haemonchus contortus, a gastrointestinal nematodes of small ruminants (sheep and goats). Egg hatching and larvicidal inhibitory effects of pod extract and fractions of P. thonnigii pods were determined using the egg inhibition assay (EIA) and larval development inhibition assay (LDIA) assay. The assay was tested in 96-flat bottom microtitre plate, using different concentrations of 0.78, 1.56, 3.125, 6.25 and 12.5 mg/ml of the experimental extracts with three replicates. The plant extract showed higher anthelmintic activity after exposing H. Contortus to the EIA and LDIA assays. It was observed that at 12.5 mg/ml, the crude extract and albendazole had 100% inhibitory effects on the ovicidal and larvicidal activities of the parasites, showing no significant difference (p>0.05) when compared, while n-butanol had significant (p<0.05) inhibitory effects on the hatching of eggs and n-butanol, ethyl acetate, petroleum ether and aqueous had significant (p<0.05) inhibitory effects on the larval development when compared with albendazole. However, the fractions tested on H. Contortus at the concentrations of 0.78, 1.56, 3.125 and 6.25 mg/ml possessed anthelmintic activity that produced above 90% ovicidal and larvicidal inhibition of the parasite. The anthelmintic effect of P.thoningii on H. contortus in this study is further subjected to confirmation through In vivo and toxicity profile studies. [ABSTRACT FROM AUTHOR]

Objective: This study aimed to explore the phytochemical constituents and anthelmintic activities of four Cassia spp. leaves against Haemonchus contortus. Materials and Methods: The extracts were prepared from four species of Cassia spp. (C. siamea, C. fistula, C. surattensis, and C. spectabilis). Phytochemical screening of the extract was done based on the Harborne method. Evaluation of the anthelmintic activities against H. contortus was done in vitro using infective larvae (L3) migration inhibition assay (LMIA). Measurement of larvae migrating was conducted through a nylon filter with a pore size of 20 μm. The doses of Cassia spp. extract implemented were 25, 50, 100, and 200 mg/ml. Results: Tannins, alkaloids, phenol hydroquinone, flavonoids, steroids, triterpenoids, and saponins were present in all the extracts, whereas alkaloids were absent in C. fistula. No triterpenoids were found in C. surattensis and C. spectabilis. Movement of H. contortus larvae was significantly inhibited after exposure to Cassia extracts at various dosage levels (p < 0.05). The test results using LMIA on L3 H. contortus showed the lowest inhibition in the negative control. Among the species of Cassia, the C. surattensis (at 200 mg/ml) showed the highest (p < 0.05) inhibition level on the larvae. The latter result corresponded to the effect of albendazole. Conclusion: Compared to other Cassia spp., C. surattensis exhibited the highest inhibition against L3 H. contortus. However, the inhibition effect of C. surattensis was still lower as compared to albendazole. [ABSTRACT FROM AUTHOR]

Highlights • F200Y (TAC) benzimidazole resistance mutation in H. placei was found on a single haplotype in multiple populations across Punjab province. • F200Y (TAC) mutations was found on multiple divergent haplotypes in H. contortus. • The P167 (TAC) and E198A (GCA) mutations were not detected in any H. contortus and H. placei populations. Abstract Benzimidazoles have been intensively (for over 40 years) used in the livestock sector, particularly in small ruminants. This has been led to the widespread emergence of resistance in a number of small ruminant parasite species, especially Haemonchus contortus. In many countries benzimidazole resistance has severely compromised the control of H. contortus in small ruminants; but there is a little information on benzimidazole resistance in H. contortus infecting buffalo and cattle. Resistance to benzimidazoles have also been reported in the large ruminant parasite, Haemonchus placei , but again there is relatively little information on its prevalence. Hence it is very important to understand how resistance-conferring mutations emerge and spread in both parasites in buffalo and cattle hosts in order to develop approaches for the recognition of the problem at an early stage of its development. The present study suggests that the F200Y (TAC) mutation is common in H. contortus , being detected in 5/7 populations at frequencies between 7 and 57%. Furthermore, 6/10 H. placei populations contained the F200Y (TAC) mutation, albeit at low frequencies of between 0.4 and 5%. The phylogenetic analysis suggests that the F200Y (TAC) mutation in H. contortus has emerged on multiple occasions in the region, with at least three independent emergences across the populations. In contrast, the F200Y (TAC) resistance-conferring mutation in H. placei is only seen on a single haplotype. A high level frequency of the resistance haplotypes in the region, suggests that the unique resistance conferring-mutation has spread from a single emergence; likely by anthropogenic animal movement. Overall, these results provide the first clear genetic evidence for the spread of benzimidazole resistance-conferring mutations to multiple different locations from a single emergence in H. placei ; while being consistent with previous small ruminant-based observations of multiple emergence of resistance mutations in H. contortus. [ABSTRACT FROM AUTHOR]

Drug resistance in helminth parasites has incurred several difficulties to livestock industry and ranked among the top public health concerns. Therefore, seeking for new agents to control parasites is an urgent strategy. In the recent years, metallic nanoparticles have been considerably evaluated for anthelmintic effects. The current research was conducted to assess possible anthelmintic impacts of zinc oxide nanoparticles (ZnO-NPs) on a prevalent gastrointestinal nematode, H. contortus. Moreover, several biomarkers of oxidative/nitrosative stress and DNA damage were measured. Various concentrations of the nanoparticle were prepared and incubated with the worms for 24 hours. The parasite mobility, mortality rate, antioxidant enzymes activities (SOD, Catalase and GSH-Px), lipid peroxidation, total antioxidant status as well as nitric oxide (NO) contents and DNA damage were determined. ZnO-NPs exerted significant wormicidal effects via induction of oxidative/nitrosative stress and DNA damage. Conclusively, ZnO-NPs can be utilized as a novel and potential agent to control and treatment of helminth parasitic infections. [ABSTRACT FROM AUTHOR]

Studies on microtubule inhibitors have shown that the loss of equilibrium between tubulin and microtubules can generate a multitude of histochemical changes in mitochondria. This disruption of balance is also considered the basis of benzimidazole anthelmintic (BZ) activity. Studies have shown that BZ does not bond to the tubulin of the BZ-resistant Haemonchus contortus, as opposed to sensitive ones. This affinity alteration can be easily recognised by changes in the optical density and can help in the classification of H. contortus mitochondria, into sensitive (dark) and resistant (clear, unmodified zones). In order to confirm this hypothesis, we started our study from albendazole (ABZ) resistant and sensible H. contortus individuals, collected from the intestinal tract of sheep, aiming towards the identification of mitochondrial features, using the Electron Microscopy Transmission (EMT) technique. The EMT has confirmed that the structure of sensitive trichostrongilian populations was affected rapidly, only four hours after ABZ treatments. The main changes that appeared in the intestinal mitochondria of sensitive helminths were: cristae thickening and decreasing in number and cellular membrane thickening. Twelve hours after anthelmintic administration, a total blocking of metabolic functionality was observed, and finally, these changes completely altered the optical density of the mitochondria. In ABZ resistant populations, the optical density has remained normal; and the cristae number, size or functionality of resistant nematode mitochondria has remained unchanged.

In vitro studies using plant extracts suggest a relationship between their polyphenol contents and their anthelmintic (AH) activity against Haemonchus contortus. High polyphenol content appears to increase the efficacy of plant extracts against H. contortus as assessed by the larval exsheathment inhibition assay (LEIA) while appearing to reduce the AH efficacy measured using the egg hatch assay (EHA). In addition, some plants lack AH activity. Therefore, the present study investigated the relationship between the contents of condensed tannins (CT), total phenols (TP), and total tannins (TT) in methanol:water extracts (70:30) obtained from ten tropical plant species consumed by small ruminants as well as their AH activity against H. contortus evaluated by LEIA and EHA. Extracts of Acacia collinsii, Lysiloma latisiliquum, Havardia albicans, Senegalia gaumeri, Mimosa bahamensis, Piscidia piscipula, Acacia pennatula, Gymnopodium floribundum, Leucaena leucocephala, and Bunchosia swartziana were examined. Positive correlations were found between the effective concentration 50% (EC) (EHA) of extracts and their CT ( r = 0.6809, P < 0.05, n = 10) and TP ( r = 0.9152, P < 0.05, n = 10) content, suggesting that their concentration negatively affected AH activity against eggs. Based on the LEIA, there was no significant association between the EC and the CT, TP, or TT of all extracts evaluated. Thus, if sheep and goats consume a complex feed mixture with high amounts of CT, TP, and TT, it might be difficult to observe an AH effect against H. contortus egg hatching . However, the AH effect upon L establishment might be feasible. [ABSTRACT FROM AUTHOR]

Faecal worm egg counts (FEC) are very important indicators in assessing the intensity of helminth infections in animal hosts and inform decisions taken in parasite control programmes. FEC are however affected by many factors which include the dose level of larval challenge, species composition of the worms, worm burden, female worm fecundity and concurrent infections to name but these few. The relevance of time of collection of faecal sample for FEC is not fully known and in most cases faeces for analysis is collected whenever feasible for the researcher on sample collection days. The significance of the time of collection of faeces on FEC was therefore investigated at two different periods of the day, morning and afternoon. Faecal samples were collected at 7-8 a.m. (morning) and at 2-3 p.m. (afternoon) on same sampling days from 6 mice and 10 West African Dwarf goat kids experimentally infected with Heligmosomoides bakeri and Haemonchus contortus respectively. FEC were conducted using the flotation and modified McMaster techniques. Overall, the 2-3 p.m. FEC tended to be higher than the 7-8 a.m. FEC in both animal species but the difference was not significant ( P > 0.05). The time of collection of faecal samples for faecal worm egg counts is therefore not a crucial factor that may significantly affect FEC in H. bakeri and H. contortus infected mice and goats respectively although it would be advisable to maintain particular periods for collection of faeces in particular experiments for best results of FEC to be obtained. [ABSTRACT FROM AUTHOR]

Microtubules are non-covalent cylindrical polymers formed by alpha- and beta-tubulin heterodimer units, crucial for cell division, intracellular transport, motility and differentiation. This makes them very attractive pharmacological targets exploited to develop different drugs such as anthelmintics, antifungals, and antineoplastics. In this work, in order to establish an in vitro target-based screen to integrate to the search for new anthelmintics, we explored the extraction of native assembly-competent tubulin from two helminth parasites: Mesocestoides vogae tetrathyridia (syn. corti, Cestoda: Cyclophyllidea), a useful cestode biological model, and Haemonchus contortus, a sheep gastrointestinal nematode of interest in livestock production. For this purpose, a novel tubulin affinity chromatography procedure was employed, based on the binding capacity of TOG (Tumor Overexpressed Gene) domain from MAPs (microtubule-associated proteins). The TOG domain of the protein Stu2 from Saccharomyces cerevisiae fused to GST (glutathione S- transferase) were produced in E. coli, and the immobilized recombinant proteins allowed for native tubulin extraction from parasites. The binding capacity of TOG1 affinity column (3.6%) was estimated using commercial porcine brain tubulin. A total amount of up to 126 μg of M. vogae tubulin was purified, whereas H. contortus tubulin co-eluted with glutamate dehydrogenase enzyme. The identity of tubulins was confirmed by western blotting and mass spectrometry. The abundance of tubulin estimated in M. vogae was 10% soluble extract, which probably could explain differences observed between tubulin purification results of both helminth parasites. [ABSTRACT FROM AUTHOR]

We conducted herein transcriptome sequencing of the ovine abomasal tissues using the Illumina HiSeq 4000 platform to segregate early and late H. contortus -infected sheep (7 and 50 days post-infected groups, respectively) from the control naive ones. A total of 548, 357 and 7 were substantially induced genes in 7 days post-infection versus uninfected-control group, 50 days post-infection versus 7 days post-infection (7 dpi), and 50 days post-infection (50 dpi) versus uninfected-control group, respectively. However, a total of 301, 355 and 11 were significantly repressed genes between 7 dpi versus uninfected-control group, 50 dpi versus 7 dpi, and 50 dpi versus uninfected-control group, correspondingly. This indicates that H. contortus infection induced a more potent activation of abomasal gene expression in the early stage of infection as compared to the late stage. Seven pathways were annotated by Kyoto Encyclopedia of Genes, and Genomes pathway analysis accounted for the significant percentage in early H. contortus infection. This study shows for the first time that both galectin-11 and matricellular protein osteopontin are up-regulated in abomasal tissue after chronic H. contortus infection, while galectin-4 is specifically down-regulated in the early infection. Additionally, our results showed that the induction or repression of these molecules is likely to determine the infection progression. [ABSTRACT FROM AUTHOR]

The objective was to evaluate the activity against Haemonchus contortus by foliage taken from three tanniferous tree species and fed to Creole male kids experimentally infected with a dose of 350 larvae of H. contortus (L3) kg-1 body weight (BW). Twenty Creole kids weighing 12 ± 2.0 kg were randomly distributed in four treatments: T1 = control without foliage, and the addition of fresh foliage (10 % of the dry matter of the total diet) of Guazuma ulmifolia (T2), Pithecellobium dulce (T3) and Acacia cochliacantha (T4). For sixty days, the activity of the foliage against H. contortus was evaluated by quantifying the reduction in the excretion of eggs per gram of feces; also, the excretion of eggs was associated with the concentration of the blood cell pack, dry matter intake and weight change in animals. The data of the evaluated variables were analyzed in a completely randomized design and a Tukey test was carried out for comparison of means (p < 0.05). The secondary compounds of P. dulce and A. cochliacanta foliage were more effective (p < 0.04) in the control of H. contortus with minor excretion of eggs (1.48 and 1.18 Log10 g-1 of feces), respectively. The hematocrit was different (p < 0.005) mainly in hemoglobin, erythrocytes, lymphocytes and eosinophils; dry matter intake (p < 0.05) and changes in total body weight (p < 0.01) were higher in kids which received P. dulce foliage (T3) with 621.5 g d-1 and 2.4 kg, respectively. It was concluded that the secondary compounds of fresh P. dulce and A. cochliacantha foliage have the potential to control H. contortus without affecting the health and productive response in kids.

Comparative studies on the efficacy of methanolic extracts of (Punicagranatum) and triclabendazoal on Haemonchusspp by using scanning electron microscope (SEM) revealed that, Punicagranatum and ACBZ showed significant effect on adult worms of Heamonchuscontortousafter 24h in vitro cultivation, the worms started to stop motion animation and paralysis leading 100 % to death of worms. Adult H. contortus: Scanning electron microscopy (SEM) of normal fresh worms showed, the mouth of the normal fresh worm was hexagonal with six semicircular rudimentary lips, lateral amphids, papillae and dorsal buccal lancet. The later was a specialized cuticular structure arising from the cuticular lining of the dorsal wall of the buccal cavity. The lancet's anterior tip and lateral edges were slightly rounded. A pair of cervical papillae was prominent and spine-like. The cuticle was transversally striated and with lateral ridges. SEM of Treated WormsH. contortusafter 24 h incubation with 50 mg/ml ethanolic extracts of Punicagranatumpeelshowed the buccal capsule which presented a smooth surface in control worm, lost their normal aspect and showed distortion with severe blebbing of the lips. The cuticle including the lips appeared to be more swollen than normal The transverse striations became less pronounced and lost their normal aspect showing longitudinal wrinkles. The treated worms showed distortion of both buccal capsule and cuticle. The lips were deformed and the cuticular surface had a wrinkled, corrugated appearance. Besides, longitudinal thickening and wrinkling of the cuticular ridges were observed. [ABSTRACT FROM AUTHOR]

Gastrointestinal parasites are one of the biggest health problems faced in sheep, mainly due to their pathogenicity and resistance to drugs used to control these parasites. Thus, the following study aimed to assess the anthelmintic efficacy of Melaleuca alternifolia against Haemonchus contortus in gerbils ( Meriones unguiculatus ) experimentally infected. Three treatments were tested: M. alternifolia essential oil, popularly known as tea tree oil (TTO), a solid lipid nanocarrier made with essential oil of Melaleuca (nanoTTO), and terpinen-4-ol (terp-4-ol). In vivo studies were performed by determining the mean worm burden of H. contortus in gerbils TTO (0.75 mL/kg); nanoTTO (0.5 mL/kg) and terp-4-ol (0.5 mL l/kg) were able to reduce 46.36%; 48.64%, and 43.18% worm burden, respectively. H. contortus increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, as demonstrated by liver injury. It was found that the TTO, nanoTTO, and terp-4-ol were not toxic to liver and kidneys since hepatic and renal functions were not affected. Moreover, terp-4-ol was able to prevent increased levels of seric AST and ALT in infected animals, indicating a hepatoprotective effect. Thus, our results indicate that TTO, nanoTTO, and terp-4-ol are safe and efficient against H. contortus infection in gerbils, and possibly the terp-4-ol may be considered the compound present in the Melaleuca alternifolia responsible for parasitic action against H. contortus. [ABSTRACT FROM AUTHOR]

The worldwide spread of resistance to anthelmintic (AH) drugs in gastrointestinal nematodes (GINs) imposes to explore alternative solutions. Amongst those, the possible use of tannin-containing nutraceuticals appears as a relevant option to replace (or decrease the frequency of) chemical-based treatments. Our objectives were to test the AH efficacy of sainfoin pellets against a multiresistant strain of Haemonchus contortus in experimentally infected lambs and to examine possible interaction between ivermectin (IVM) and condensed tannins (CT)-rich ressource. In vivo study was performed with twenty-four lambs were inoculated (Day 0) with multiresistant H. contortus infective larvae. On D21 Post-Infection, the lambs were assigned to two dietary treatments (sainfoin vs lucerne control pellets). On D39, half of the animals per group received 0.25 ml/kg of an oral ivermectin treatment. On D47, animals were slaughtered to count worms. The consumption of sainfoin was associated with higher packed cell volume (PCV) values (P < 0.05) and reduced faecal egg counts (FECs) (P < 0.05). For the experimental feeding period, FECs were overall reduced by 50% in the sainfoin group. The diet did not have significant effect on the worm number but sainfoin significantly reduced female fertility. Decrease in plasma IVM concentrations was observed in the sainfoin-fed animals and was associated with a decrease of IVM efficiency when compared with the control group. Incubating tannin in vitro with ivermectin and rumen fluid showed a blocking of ivermectin by the tannins. This suggests that tannins lower the IVM intestinal absorption compromising thereby drug plasma bioavailability and efficacy. Tannin-containing nutraceuticals alter the biology of multiresistant nematodes, thus representing an option for their sustainable control. In vivo and in vitro interactions between nutraceuticals and chemicals impose caution when both tannin-rich diet and drug-based treatments are combined. Further studies are required to clarify the mechanisms that support such interactions. [ABSTRACT FROM AUTHOR]

This study was designed to determine dynamic dispersal, treatment of Haemonchus contortus and its effect on blood profile of small ruminants in district Lodhran, Punjab. Out of total 646 animals, 30% (97/323) sheep and 25% (81/323) goats were found positive. The prevalence was found associated with seasons and body condition score. They were treated with the combination of triclabendazole and levamisole, Mallotus philippensis and Fumaria indica Triclabendazole and levamisole combination was the most effective treatment in order followed by kamila (Mallotus philippensis) and shahtrah (Fumaria indica).The statistical analysis of blood profile showed significant (P<0.05) decrease in red blood cells, haemoglobin, pack cell volume, total serum protein concentration, serum albumin and significant (P<0.05) increase in eosinophil number and serum enzymes level in infected animals. In conclusion, H. contortus may be considered as endemic in study area. [ABSTRACT FROM AUTHOR]

We describe a case of anthelmintic resistance on one of the largest organic small ruminant farms in Denmark. The flock was established in 2007 by purchase of animals from other Danish farms and had history of clinical parasitism, high mortality of young stock and anthelmintic treatment failure. In October 2011, 40 lambs and 40 kids were selected for a faecal egg count reduction test (FECRT) with fenbendazole (FBZ), ivermectin (IVM), moxidectin (MOX) and levamisole (LEV). Lambs were treated with the recommended sheep dose of each product while kids received the sheep dose of IVM, 1.5× sheep dose of MOX and 2× sheep dose of FBZ and LEV. Untreated lambs and kids were also included and three methods for calculating faecal egg count (FEC) reduction were compared. In a subsequent investigation, a controlled efficacy test (CET) with FBZ and IVM was performed in lambs infected with Haemonchus contortus and Trichostrongylus colubriformis isolated from adult goats on the farm. Recovered specimens of H. contortus were subjected to pyrosequencing for detection of single nucleotide polymorphisms (SNPs) related to benzimidazole (BZ) resistance. During the FECRT, FECs in untreated lambs dropped significantly by 47%. No FEC reduction was detected in untreated kids. After FBZ treatments, FEC reductions in lambs and kids ranged from 15 to 54% and 49–56%, respectively, according to the different calculation methods. Post IVM treatments, FEC reductions in lambs and kids varied between 71–90% and 81–83%, correspondingly. LEV and MOX reduced FECs by 98–100% in both species. In the CET, FBZ reduced H. contortus worm counts by 52–56% and no reduction in T. colubriformis counts were detected after treatment. IVM eliminated 100% of H. contortus and reduced T. colubriformis counts by 84–92%, according to different calculation methods. Pyrosequencing of isolated H. contortus revealed increased frequencies of the BZ resistance-related SNP in codon 200 of the β-tubulin isotype 1 gene. Frequency of BZ resistance-related SNPs in codons 167 and 198 were very low and did not exceed levels as obtained in the susceptible reference isolate. Anthelmintic resistance was confirmed in this recently established organic farm and low field efficacy of FBZ was verified by CET and pyrosequencing. BZ-resistant populations of H. contortus and T. colubriformis were isolated for the first time in Denmark. Problems with correct dosing of goats, the observed FEC reduction in untreated lambs and the relevance of including a control group in the FECRT are discussed. [ABSTRACT FROM AUTHOR]

Mediante el uso del Análisis Discriminante aplicado a una serie de criterios morfométricos clásicos en la descripción de nematodos fueron puestos en evidencia tanto variaciones intraespecificas de H. contortus en relación al hospedador (ovejas o cabras), as¡ como también la existencia de diferencias entre las especies gemelas H. placei y H. contortus. La validez de la especie H. similis fue confirmada.

Haemonchus contortus is an economically important gastrointestinal parasite that infects primarily sheep and goats. To survive inside the host, the parasite must overcome the host immune response. In this study, we have identified and characterized a complement-C3-binding protein (H.c-C3 BP) from this parasite employing biochemical and molecular biology tools. Initially, a truncated form of the protein was isolated from the excretory-secretory products of the parasite using C3-Sepharose column that facilitated its identification by mass spectroscopy. Subsequently, the parent molecule was generated in E. coli, and sequence analysis confirmed it as glyceraldehyde-3-phosphate dehydrogenase ( GAPDH). GAPDH reacted with the antiserum raised against the truncated protein, and the truncated protein reacted with anti- GAPDH antiserum. The protein inhibited complement function as measured by haemolytic assay and membrane attack complex ( MAC) formation. Sera from H. contortus-infected animals reacted with GAPDH as well as the truncated form of the protein, which further lend support to protein secretion. Thus, the C3-binding property of H. contortus GAPDH is a new function, and it represents a new entity of complement-binding protein. Identification and characterization of H.c-C3 BP should facilitate development of new therapeutics considering a key role of this protein in immune modulation. [ABSTRACT FROM AUTHOR]

Highlights: [•] Aqueous leaf extract of Annona muricata is effective against eggs, L3 lavae and adults of Haemonchus contortus. [•] Aqueous leaf extract of A. muricata is rich in phenolic compounds. [•] This work validated the ethnopharmacological potential of A. muricata. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate oxidative stress in lambs experimentally infected with Haemonchus contortus and supplemented with selenium and vitamin E. Twenty male Corriedale lambs were divided into four experimental groups with five animals each: G1 consisted of animals infected and supplemented with 0.2 mg/kg of live weight (LW) sodium selenite by intramuscular injection (IM); G2 consisted of animals infected with larvae and supplemented with 0.2 mg/kg LW sodium selenite IM and 2000 IU per animal of Vitamin E IM; G3 consisted of animals infected with larvae and supplemented with 2000 IU per animal of Vitamin E IM; and G4 consisted of animals infected with larvae. The animals were infected orally with 500 H. contortus larvae (L3) every 48 hours for 20 days. For biochemical analyses and eggs per grams of feces (EPG) evaluation, blood and feces were both collected at zero (T0), 20 (T1), 40 (T2) and 60 (T3) days. The weight of the animals was also measured at these times. Lower TBARS values were observed in the supplemented animals compared to the control group. The groups supplemented with Selenium exhibited blood GSH-Px activity higher than that of non-supplemented animals. Supplementation with selenium provided greater antioxidant protection against oxidative stress generated from experimental infection of lambs with H. contortus. [ABSTRACT FROM AUTHOR]

Abstract: Haemonchus contortus is an economically important gastrointestinal parasite of domestic animals. The parasite secretes calreticulin (CalR), a Ca++ binding protein which modulates the host immune response. One way by which this protein acts is by inhibiting the classical complement pathway by binding to complement C1q protein. Understanding CalR–C1q interaction is important to develop methods to enhance host immune response. In this study, we have mapped the regions in the N-domain of CalR that facilitates C1q binding by generating small recombinant fragments of the domain and using synthetic peptides. In addition to already identified C1q binding motifs in human CalR, two additional sites in the N-domain of H. contortus were revealed with the following sequences—GKYYDDAKRD and the AKFPKKFT. The significance of multiple C1q binding motifs in CalR is discussed in relation to host–parasite interactions. [Copyright &y& Elsevier]

Abstract: Members of the PAR-1/MARK serine/threonine protein kinase (STK) subfamily are important regulators of the cytoskeleton, and their characterization can provide insights into a number of critical processes relating to the development and survival of an organism. We previously investigated the mRNA expression for and organization of a gene (hcstk) representing HcSTK, an STK from the parasitic nematode Haemonchus contortus. In the present study, a recombinant form of HcSTK was expressed and characterized. Affinity-purified anti-HcSTK antibodies reacted with native HcSTK in protein homogenates extracted from third-stage larvae (L3) of H. contortus and were also used to immunolocalize the protein around the nuclei of ovarian and intestinal tissues of adult H. contortus. The enzyme activity of the recombinant HcSTK protein was also demonstrated. The findings show that recombinant HcSTK is a functional protein kinase, with activity directed to KXGS motifs, consistent with other members of the PAR-1/MARK STK subfamily. [Copyright &y& Elsevier]

The effect of Ivomec was studied against stomach large worm H. contortus in experimental Awasi lambs through infection of 500 infective larvac per Kg body weight. Result revealed that Ivomec has high efficacy reaching 100%. Two weeks post treatment, improvment of blood parameter was recorded 3 weeks post treatment indicating its effectivness, there was also decrease in the number of eggs per gram which vanished 2 weeks post treatment. This indicated that Ivomec with a fixed dose has high efficacy against H. contortus the most spread helminth in Iraq