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Controlling parasites in zoo animals is a significant challenge, making practical infection prevention methods essential. This study evaluated a novel solution using parasitophagous fungi-treated forage seeds to reduce soil parasite persistence. We conducted two experiments to assess the soil distribution of the fungi Mucor circinelloides (ovicidal) and Duddingtonia flagrans (larvicidal). Forage seeds were immersed in a submerged culture containing 106 spores/mL and subsequently sown in plastic trays (trial 1) and demarcated ground plots (40 × 30 cm) framed with wood (trial 2). Fifteen days later, Ascaris suum and cyathostomin eggs were placed above the germinated vegetation. After a 25–30-day period, the viability of roundworm eggs reduced by 62%, and half of them remained undeveloped; a 64% reduction in the counts of L3 cyathostomins was recorded. In trial 2, viability decreased by 55% in roundworm eggs, with an infectivity rate of 30%, while L3 counts lessened by 57%. It has been concluded that the risk of infection by ascarids and cyathostomins can be reduced by at least half by sowing the soil with forage seeds pre-treated with fungi, providing a practical solution for parasite control in zoos. [ABSTRACT FROM AUTHOR]

The filtrate of the nematophagous fungus Duddingtonia flagrans produces silver nanoparticles (AgNPs) with nematicidal potential. However, there are currently no reports of its activity against Toxocara canis eggs. The aim of this study was to investigate the potential ovicidal activity of AgNPs–D. flagrans on T. canis eggs. T. canis eggs were obtained from the dissection of the uterus of adult female nematodes. After the biosynthesis of AgNPs, two experimental assays (A and B) were performed. In assay A, the ovicidal activity of AgNPs on eggs was evaluated after 15 and 30 days of interaction. In assay B, the inhibition (development) of the eggs was measured after 30 days of interaction. The results of assay A showed that the AgNPs destroyed an average of 47% of the eggs tested by the end of the experiment, causing significant structural damage. In assay B, an inhibition rate of 88% was observed at the end of 30 days. The results of the ovicidal activity of AgNP–D. flagrans were promising and indicate the potential for future studies on these biomolecules with ovicidal properties. [ABSTRACT FROM AUTHOR]

Definition: In recent decades, important modifications have been introduced in zoos in order to guarantee the welfare of captive wild animals. Thus, many of these species are housed in enclosures with access to vegetation, where they can enjoy habitats close to those in their natural surroundings, interact with the environment, etc. These habitats present beneficial conditions for some species of parasites to survive and spread. This is a very similar problem to that affecting livestock, and the same solution, based on deworming, is currently being applied. However, the free-living stages of certain parasites that develop in the soil are responsible for high rates of ground contamination throughout the year, so that animals become infected soon after successful deworming, resulting in chemical parasiticides being frequently administered. Preventive measures are seldom considered, which worsens the situation. This entry summarizes the usefulness of the dissemination of certain saprophytic filamentous fungi with proven antagonism against some of the parasites. [ABSTRACT FROM AUTHOR]

Nematophagous fungi are a biological control tool used against gastrointestinal nematodes in livestock. These fungi prey on free-living larvae in faeces and could be affected by active drugs excreted post-treatment. This study aimed to determine in vitro and under environmental conditions the effect of the following anthelmintics on the fungus Duddingtonia flagrans: ivermectin, levamisole, albendazole, fenbendazole and ricobendazole. The in vitro effect of anthelmintics on fungal growth and predatory capacity was assessed in corn meal agar and coprocultures, respectively. Ivermectin (1, 2 and 10 ppm), fenbendazole (0.027, 0.054 and 1 ppm) and albendazole (1 ppm) significantly affected fungal development. The fungal efficacy against L3 was high in the control and levamisole coprocultures but decreased significantly in the presence of albendazole, fenbendazole, ricobendazole and ivermectin. The impact of levamisole on D. flagrans was further assessed under environmental conditions in autumn and winter; the fungal efficacy measured in faecal pats and the surrounding herbage was not affected by levamisole at any time. This study shows that using albendazole, fenbendazole, ricobendazole or ivermectin may compromise fungal activity, as these drugs affect the free-living stages of nematodes in faeces, but levamisole can be safely considered in parasite control strategies involving D. flagrans and anthelmintic treatments. [ABSTRACT FROM AUTHOR]

Nematophagous fungi are a biological control tool used against gastrointestinal nematodes in livestock. These fungi prey on free-living larvae in faeces and could be affected by active drugs excreted post-treatment. This study aimed to determine in vitro and under environmental conditions the effect of the following anthelmintics on the fungus Duddingtonia flagrans: ivermectin, levamisole, albendazole, fenbendazole and ricobendazole. The in vitro effect of anthelmintics on fungal growth and predatory capacity was assessed in corn meal agar and coprocultures, respectively. Ivermectin (1, 2 and 10 ppm), fenbendazole (0.027, 0.054 and 1 ppm) and albendazole (1 ppm) significantly affected fungal development. The fungal efficacy against L3 was high in the control and levamisole coprocultures but decreased significantly in the presence of albendazole, fenbendazole, ricobendazole and ivermectin. The impact of levamisole on D. flagrans was further assessed under environmental conditions in autumn and winter; the fungal efficacy measured in faecal pats and the surrounding herbage was not affected by levamisole at any time. This study shows that using albendazole, fenbendazole, ricobendazole or ivermectin may compromise fungal activity, as these drugs affect the free-living stages of nematodes in faeces, but levamisole can be safely considered in parasite control strategies involving D. flagrans and anthelmintic treatments.

The filtrate of the nematophagous fungus Duddingtonia flagrans produces silver nanoparticles (AgNPs) with nematicidal potential. However, there are currently no reports of its activity against Toxocara canis eggs. The aim of this study was to investigate the potential ovicidal activity of AgNPs–D. flagrans on T. canis eggs. T. canis eggs were obtained from the dissection of the uterus of adult female nematodes. After the biosynthesis of AgNPs, two experimental assays (A and B) were performed. In assay A, the ovicidal activity of AgNPs on eggs was evaluated after 15 and 30 days of interaction. In assay B, the inhibition (development) of the eggs was measured after 30 days of interaction. The results of assay A showed that the AgNPs destroyed an average of 47% of the eggs tested by the end of the experiment, causing significant structural damage. In assay B, an inhibition rate of 88% was observed at the end of 30 days. The results of the ovicidal activity of AgNP–D. flagrans were promising and indicate the potential for future studies on these biomolecules with ovicidal properties.

Abstract Parasitic resistance imposes alternative control methods, like nematophagous fungi. In this study, two experiments were conducted supplying Duddingtonia flagrans aiming to evaluate the biological control of parasites in sheep. In the first, 24 sheep naturally infected by gastrointestinal nematodes were allocated, in randomized blocks, following the treatments: control or treated group, 0.5g/animal product containing D. flagrans, chlamydospores. Weight, body score, Famacha©, egg count per gram of feces (EPG), and larval percentage were evaluated. In the second experiment, D. flagrans (0.25 and 0.5g product) was infested with manure, plus or not protein concentrate, in a completely randomized design. In both experiments the dose was intentionally lower than recommended. Recovery and larval identification were performed. The SAS analyzed the variables by the MIXED procedure, repeated measures in time. Weight, body score, hematocrit, and Famacha© did not show differences between treatments (p>0.05); however, EPG (p0.05). In both experiments, colonization and advancement of the fungus were visualized. Under the experimental conditions, the fungus D. flagrans was not effective in the biological control of parasitic infection in sheep.

Control of infection by gastrointestinal nematodes remains a big problem in ruminants under continuous grazing. For the purpose of decreasing the risk of infection by Trichuris sp. in captive bison (Bison bison) always maintained in the same plot, dried gelatins having ≥106 chlamydospores of both Mucor circinelloides and Duddingtonia flagrans were given to them for one week, and at the end, fecal samples (FF) collected each week for four weeks were analyzed immediately. Feces taken one week prior to gelatin administration served as controls (CF). Eggs of Trichuris sp. were sorted into non-viable and viable, then classified into viable undeveloped (VU), viable with cellular development (VCD), or viable infective (VI). Ovistatic and ovicidal effects were determined throughout the study. In FF, viability of Trichuris eggs decreased between 9% (first week) and 57% (fourth week), egg development was delayed during the first two weeks, and VI percentages were significantly lower than in CF (p = 0.001). It is concluded that the preparation of gelatins with chlamydospores of parasiticidal fungi and their subsequent dehydration offer an edible formulation that is ready to use, stress-free to supply, and easy to store, as well as being well-accepted by ruminants and highly efficient to reduce the risk of Trichuris sp. infection among animals under continuous grazing regimes. [ABSTRACT FROM AUTHOR]

Following a request from the European Commission, the Panel on Additives and Products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety of a feed additive consisting of Duddingtonia flagrans NCIMB 30336 (BioWorma®) for all grazing animals. The safety and efficacy of the additive have been already assessed previously, however the FEEDAP Panel could not conclude on the safety of the additive for the target species and the consumers due to the limitations in the dataset provided. For the current assessment, the applicant submitted a new tolerance trial in dairy cows and new toxicological studies. After the assessment of the new data submitted, the FEEDAP Panel concluded that the use of the feed additive in animal nutrition under the conditions of use proposed is of no concern for dairy cows. This conclusion can be extrapolated to all dairy bovines, ovines and caprines, but not to fattening and rearing animals of those species. Due to the lack of data, the FEEDAP Panel cannot conclude on the safety of the additive for other grazing species/categories. The FEEDAP Panel concluded that the additive is safe for the consumers. [ABSTRACT FROM AUTHOR]

The purpose of using nematophagous fungi as biological control agents of gastrointestinal nematodes of livestock is to reduce the build-up of infective larvae on pasture and thus avoid clinical and subclinical disease. As the interaction of fungus-larval stages takes place in the environment, it is crucial to know how useful the fungal agents are throughout the seasons in areas where livestock graze all year-round. This study was designed to determine the predatory ability of the nematophagous fungus Duddingtonia flagrans against gastrointestinal nematodes of cattle during four experiments set up in different seasons. In each experiment, faeces containing eggs of gastrointestinal nematodes were mixed with 11,000 chlamydospores/g and deposited on pasture plots. A comparison between fungal-added faeces and control faeces without fungus were made with regard to pasture infectivity, larval presence in faecal pats, faecal cultures, faecal pat weight, and temperature inside the faecal mass. In three of the four experiments, Duddingtonia flagrans significantly reduced the population of infective larvae in cultures (68 to 97%), on herbage (80 to 100%), and inside the faecal pats (70 to 95%). The study demonstrated the possibility of counting on a biological control tool throughout most of the year in cattle regions with extensive grazing seasons. [ABSTRACT FROM AUTHOR]

Control of infection by gastrointestinal nematodes remains a big problem in ruminants under continuous grazing. For the purpose of decreasing the risk of infection by Trichuris sp. in captive bison (Bison bison) always maintained in the same plot, dried gelatins having ≥106 chlamydospores of both Mucor circinelloides and Duddingtonia flagrans were given to them for one week, and at the end, fecal samples (FF) collected each week for four weeks were analyzed immediately. Feces taken one week prior to gelatin administration served as controls (CF). Eggs of Trichuris sp. were sorted into non-viable and viable, then classified into viable undeveloped (VU), viable with cellular development (VCD), or viable infective (VI). Ovistatic and ovicidal effects were determined throughout the study. In FF, viability of Trichuris eggs decreased between 9% (first week) and 57% (fourth week), egg development was delayed during the first two weeks, and VI percentages were significantly lower than in CF (p = 0.001). It is concluded that the preparation of gelatins with chlamydospores of parasiticidal fungi and their subsequent dehydration offer an edible formulation that is ready to use, stress-free to supply, and easy to store, as well as being well-accepted by ruminants and highly efficient to reduce the risk of Trichuris sp. infection among animals under continuous grazing regimes.

The innocuousness of the prolonged ingestion of commercial nutritional pellets containing spores of the fungal species Mucor circinelloides and Duddingtonia flagrans on grazing dairy heifers was tested. During two years, one group (G-F) received daily 2.5 kg pellets with 3 × 105 spores each fungus / kg pellet, and group G-C without them. In the third year, ruminants in both groups received spore-free feed. Evaluation of red and white blood cell parameters (RBC and WBC, respectively) was performed monthly. Alterations on the digestive activity, respiratory function and reproductive functionality were also recorded. Three heifers of G-F were necropsied in the second year of study and four in the third. Samples collected from different tissues and organs were preserved in 10% neutral buffered formalin, sections included in paraffin and stained with haematoxylin/eosin, periodic acid Schiff, Fontana–Masson and Ziehl–Neelsen. During the first two years, normal numbers of RBC and WBC were recorded in G-F, by values of RBC and haemoglobin (HB) below physiological standards in G-C. No differences between the two groups were obtained in the third year, with RBC and HB levels lower than normal (physiological). No fungal structures or lesions related to fungal administration were visualised in the tissues of G-F. It is concluded that the daily ingestion of pellets containing spores of the parasiticidal fungi M. circinelloides and D. flagrans over a long period of time is completely safe. [ABSTRACT FROM AUTHOR]

The importance of biological control in agriculture and livestock has led to an increase in the investigation into efficient microorganisms for the control of diseases and pests. In this context, the fungus Duddingtonia flagrans has been studied for the management of parasitic nematodes in domestic animals, alongside recent investigations on plant parasitic nematodes and plant development. In addition to capturing nematodes through the production of traps in the soil, this nematophagous fungus also develops in the root and promotes plant growth. This review aims to summarise the main information about D. flagrans and demonstrate how much the application of this fungus has increased in recent years. [ABSTRACT FROM AUTHOR]

The purpose of the study was to analyze the antitumor effects of the extract of mycelium from Duddingtonia flagrans (strain F-882) on xenografts of human C33a cervical cancer cells.Material and Methods. To evaluate the antitumor effect, we used the absolute values of xenograft volumes and calculated the tumor growth inhibition and the index of tumor growth.Results. At the first stage of the experiment, a 4-week subcutaneous injection of the water extract of F-882 resulted in an almost twofold slowdown in xenograft growth, with the tumor growth inhibition value of 50.6 %. In the second stage of the experiment, a 2.5-week subcutaneous injection followed by a 1.5-week intratumoral injection of F-882 also caused the tumor growth inhibition. After completing F-882 injections, the effect of tumor growth inhibition continued for 2.5 weeks and the tumor growth inhibition value was 58.7 %.Conclusion. The mycelium extract F-882 was shown to have an antitumor effect on subcutaneous xenografts of human C33a cervical carcinoma cells.

The purpose of using nematophagous fungi as biological control agents of gastrointestinal nematodes of livestock is to reduce the build-up of infective larvae on pasture and thus avoid clinical and subclinical disease. As the interaction of fungus-larval stages takes place in the environment, it is crucial to know how useful the fungal agents are throughout the seasons in areas where livestock graze all year-round. This study was designed to determine the predatory ability of the nematophagous fungus Duddingtonia flagrans against gastrointestinal nematodes of cattle during four experiments set up in different seasons. In each experiment, faeces containing eggs of gastrointestinal nematodes were mixed with 11,000 chlamydospores/g and deposited on pasture plots. A comparison between fungal-added faeces and control faeces without fungus were made with regard to pasture infectivity, larval presence in faecal pats, faecal cultures, faecal pat weight, and temperature inside the faecal mass. In three of the four experiments, Duddingtonia flagrans significantly reduced the population of infective larvae in cultures (68 to 97%), on herbage (80 to 100%), and inside the faecal pats (70 to 95%). The study demonstrated the possibility of counting on a biological control tool throughout most of the year in cattle regions with extensive grazing seasons.

The striatin-interacting phosphatase and kinase (STRIPAK) complex is a highly conserved eukaryotic signaling hub involved in the regulation of many cellular processes. In filamentous fungi, STRIPAK controls multicellular development, hyphal fusion, septation, and pathogenicity. In this study, we analyzed the role of the STRIPAK complex in the nematode-trapping fungus Duddingtonia flagrans which forms three-dimensional, adhesive trapping networks to capture Caenorhabditis elegans. Trap networks consist of several hyphal loops which are morphologically and functionally different from vegetative hyphae. We show that lack of the STRIPAK component SipC (STRIP1/2/HAM-2/ PRO22) results in incomplete loop formation and column-like trap structures with elongated compartments. The misshapen or incomplete traps lost their trap identity and continued growth as vegetative hyphae. The same effect was observed in the presence of the actin cytoskeleton drug cytochalasin A. These results could suggest a link between actin and STRIPAK complex functions. [ABSTRACT FROM AUTHOR]

Copyright of Mustafa Kemal University Journal of Agricultural Sciences / Mustafa Kemal Üniversitesi Tarım Bilimleri Dergisi is the property of Mustafa Kemal University, Faculty of Agriculture and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We describe the synthesis and a function of melanin in Duddingtonia flagrans, a nematode-trapping fungus. We tested various culture media treated with L-DOPA, glucose and tricyclazole on fungal growth and melanin distribution using infrared spectroscopy (IS), electron paramagnetic resonance (EPR) and transmission electron microscopy (TEM). In vitro rumen digestion was used to test the environmental stress and then to evaluate the capacity of this fungus to trap nematode larvae. The growth and melanization of the fungus after 21 days of incubation at 30°C were best in Sabouraud dextrose medium. IS indicated the presence of melanin in D. flagrans, with similar bands for commercial melanin used as a control, and assigned the values obtained by EPR (g of 2.0051 ± 0.0001) to the production of melanin by the fungus. TEM indicated that melanin was produced in melanosomes but was not totally inhibited by tricyclazole. Within the limits of experimental error, the predatory activity of fungus treated with tricyclazole was drastically affected after 27 h of in vitro anaerobic stress with rumen inoculum. The deposition of melanin particles on the fungal cell wall contributed to the maintenance of D. flagrans predatory abilities after in vitro anaerobic ruminal stress.

A 14-d study was undertaken to test the acute toxicity of a new preparation Vetom 21.77 based on the predacious fungus Duddingtonia flagrans. A total of 40 healthy 5-day-old broiler chickens (Hubbard F15, 100 ± 5 g), that had previously gone through a required 5-days adaptation to the environment, were orally dosed with the drug for 5 consecutive days at different doses, after which their health status was assessed daily up to the end of the experiment. According to the results, no substantial changes in the physiological state of the chickens were detected during the experiment. Internal organs weighing revealed no statistically significant differences between the groups, though weight coefficient values of internal organs of treated chickens slightly exceeded those of the control group. Some haematological parameters were significantly higher in the treatment group, without going beyond reference ranges. All chickens used in the experiment survived the study. The preparation has not produced any toxic effect even at a higher dose (4000 µL/kg bw/day). It is concluded that Vetom 21.77 pertains to preparations of IV toxicity class.

Copyright of Journal of Northwest A & F University - Natural Science Edition is the property of Editorial Department of Journal of Northwest A&F University (Natural Science Edition) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Summary: Pratylenchus brachyurus is considered one of the most important plant pathogens of soybean and corn in Brazil, mainly found in areas where no-tillage is practised. Nematophagous fungi are used as an alternative for chemical nematicides in the management of nematodes that affect these crops in Brazil. This study evaluated the fungi Pochonia chlamydosporia , Trichoderma sp. and Duddingtonia flagrans for the biocontrol of P. brachyurus in soybean and corn. The first and second experiments were carried out using soybean, and five isolates of P. chlamydosporia (Pc-3, Pc-4, Pc-10, Pc-35 and Pc-49), one of Trichoderma sp. (T-10), an isolate of D. flagrans (AC001) and a mix (MIX) of all the isolates. In the third experiment using corn, three isolates of P. chlamydosporia (Pc-3, Pc-10 and Pc-35) and one isolate of Trichoderma sp. (T-10) were compared. In the first experiment, the isolates Pc-3, Pc-10, Pc-35 and T-10 reduced the total population of P. brachyurus up to 43.7% when compared with the control treatment. In the second experiment, the isolates Pc-10, T-10 and the MIX reduced the total population of P. brachyurus up to 58.7% when compared with the control. In the third experiment, the isolates reduced the total population of P. brachyurus in corn when compared with the control treatment, except for D. flagrans , which was not able to control P. brachyurus in any experiment. The P. chlamydosporia (Pc-3, Pc-10, Pc-35) and Trichoderma sp. (T-10) isolates were shown to be promising for the control of P. brachyurus in soybean and corn. [ABSTRACT FROM AUTHOR]

The objective of the present study was to evaluate the biological control of nematodes in young ewes receiving the fungi Duddingtonia flagrans (AC001) and Monacrosporium thaumasium (NF34) orally. The subjects were 40 Texel sheep, all female, between 12 and 24 months of age. At the beginning of the experiment, all animals received an oral dose of ivermectin. After 14 days, the animals were separated in four homogeneous groups of 10 animals: Group 1 received 3 g/10 kg of pellets containing mycelium of AC001 body weight twice a week; Group 2 received 3 g/10 kg of pellets containing mycelium of NF34 body weight twice a week; Group 3 received two doses of ivermectin (0.2 mg/kg of live weight) two and five months after the beginning of experiment (in the months of December and March) and Group 4, control, was untreated. Feces of each animal were collected weekly and every 14 days approximately 500 g of pasture crops were harvested of each pickets where the groups were located. The results show that AC001 and NF34 were efficient in reducing egg count per gram of feces (P < 0.05) and the count of L3 in pastures. At the end of the experiment, the group of animals treated with AC001 presented 17.2 kg of weight gain accumulated in relation to other experimental groups. The fungi D. flagrans (AC001) and M. thaumasium (NF34) were efficient in the control of gastrointestinal nematodes in young ewes, promoting a decreased recurrence of infection, reflecting directly on the weight gain. [ABSTRACT FROM AUTHOR]

The oral application of chlamydospores of the nematophagous fungus Duddingtonia flagrans allows reducing the number of infective larvae (L3) in faeces and decreases the infectivity of the pastures of gastrointestinal nematodes. There are differences in the literature about the quantity of chlamydospores required for the reduction of L3 and there is little data about the importance of the concentration of parasite eggs in faeces in relation to the predatory effect of fungus. This study evaluated the reduction of L3 in faeces taking into account four concentrations of chlamydospores of D. flagrans with four concentrations of faecal eggs per gram (epg). Two hundred coprocultures were performed with 10 g each one, using faeces from four parasitised sheep with natural infections. The coprocultures were distributed in treated groups (GT) containing 180, 620, 1460 and 3600 epg along with 1000, 6250, 3000 and 11,000 chlamydospores per gram of faeces. Four control groups without chlamydospores were performed for each GT. The coprocultures were incubated for 16 days at room temperature of 27°C. The reduction percentages for the group of 11,000 chlamydospores and epg 180, 620, 1460 and 3600 were 6.51%; 1.35%; 52% and 85%, respectively. In the group of 6250 chlamydospores the reduction percentages for epg 180, 620, 1460 and 3600 were 16%; 20%; 66% and 67%, respectively. These results would indicate that the predatory capacity of D. flagrans can be dependent on the stimulus generated by the presence of larvae as well as the concentration of chlamydospores present in the faeces. [ABSTRACT FROM AUTHOR]

Abstract Following a request from the European Commission, the EFSA Panel on Additives and products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of BioWorma® (Duddingtonia flagrans NCIMB 30336) when used as a zootechnical feed additive for all grazing animals. Duddingtonia flagrans belongs to a group of nematophagous fungi that physically entrap nematodes through an adhesive hyphal net. The additive contains the fungus in the form of chlamydospores and is intended to control pathogenic nematodes on pasture, with subsequent benefits for grazing animals. No conclusions could be drawn on the safety for the target species due to lack of data. ■■■■■ As it is not possible to exclude the presence of secondary metabolites (other than flagranones) produced during fermentation and their potential carry‐over into animal products, safety for the consumer could not be established. The Panel concluded that the additive is not irritant to skin and eyes but is irritant to the respiratory tract and a respiratory sensitiser. No conclusion could be drawn on its skin sensitisation potential. Since D. flagrans is a naturally inhabiting soil organism of world‐wide distribution, the Panel considered that use of an additive based on this organism does not pose a risk for the environment under the intended conditions of use. The strain under application reduced the number of parasitic nematodes on pasture to the benefit of grazing animals when used at the recommended application rate of 3 × 104 chlamydospores/kg bodyweight and day.

It is known that predatory Hyphomycetes fungi play an important role in measures taken for helminthic infestation prevention. There is little evidence on properties of compounds contained in predatory fungi and their effect on animals. Results of tests of "Vetom 21.77", new microbiological preparation based on Duddingtonia flagrans, for its effect on serum biochemical pattern of laboratory mice are presented. The preparation was administered to the animals at the dose of 2, 5, 50 and 300 µl/kg of body weight. The animals were examined for tested parameters prior and 2 and 7 days after daily administration of the preparation. The parameters remained within the normal physiological limits in all test group as well as in control group not given the preparation. The test results indicated safety of the said microbiological preparation. Significant increase in total protein and albumin contents was recorded in mice given the maximum dose of the preparation as compared with those of control group.

Abstract Background An approach to preventing strongyle infection in horses was tested, comprising rotational pasturing and the administration of spores of two parasiticidal fungi, Mucor circinelloides and Duddingtonia flagrans. Methods Twenty-two adult Spanish Sport Horses were dewormed with ivermectin (1 mg pour-on/kg body weight) and then randomly divided into three groups. G-1 was maintained with continuous grazing, and G-2 and G-3 were kept on a four-paddock rotation system. Commercial pelleted feed (2.5 kg/horse) was supplied to G-1 and G-2 twice a week; horses in G-3 received pellets containing 2 × 106 spores/kg of each fungus. Fecal samples were analyzed by the flotation method to estimate the reduction in the fecal egg counts (FECR), the percentage of horses shedding eggs (PHR), and the egg reappearance period (ERP). Results Third-stage larvae were identified in fecal pats as Cyathostomum (sensu lato) types A, C and D, Gyalocephalus capitatus, Triodontophorus serratus, Poteriosthomum spp., Strongylus vulgaris and S. edentatus. Two weeks after treatment, the FECR values were 100% in G-1, 96% in G-2 and 99% in G-3; the PHR values were 100% in G-1, 75% in G-2 and 88% in G-3. A strongyle ERP of 6 weeks was observed in G-1, ERP of 10 weeks was observed in G-2, and ERP of 16 weeks was observed in G-3. The counts of eggs per gram of feces (EPG) were > 300 EPG in G-1 and G-2 but remained below 250 EPG in G-3 throughout the observation period of 12 months. Conclusions These results suggest that horse strongyle infection could be decreased by combining rotational pasturing with feeding pellets containing the spores of parasiticidal fungi.

This study aimed to evaluate the efficiency of the powdered formulation with the nematophagous fungi Duddingtonia flagrans against gastrointestinal nematodes of sheep under three feeding systems in Northern China. Each animal in the treatment group received approximately 5×105 spores/kg live weight at twice a week for 6 months. The control group received an equal amount of feeds without fungus. In the grazing system, two herds were selected in the Tongyu County in Northeast China. Among them, 70 sheep as the treatment group and 100 sheep as the control group. These results revealed that fungal group showed a greater reduction in eggs per gram of feces (EPG), infective larvae (L3) per kilogram in pasture and larvae per gram of feces (LPG) after administration and lower parasitic load burden in the tracer lambs compared with the control group (p<0.05). In the semi-confinement system, 20, 15, and 15 sheep from three individual farmers were selected from Zhangye City of Northwestern China; 20 sheep as the control group and the remaining sheep as the treatment group. The fungal group showed a greater reduction in EPG after 150 and 180 days and LGP from 60~180 days after administration (p<0.05). In the confinement feeding system, 40 lambs were randomly divided into the treatment and control groups. The results showed that no differences in EPG and LGP were observed in the two groups (p>0.05). In conclusion, the powder was efficient in controlling sheep gastrointestinal helminths under three feeding systems in Northern China. [ABSTRACT FROM AUTHOR]

Following a request from the European Commission, the EFSA Panel on Additives and products or Substances used in Animal Feed (FEEDAP) was asked to deliver a scientific opinion on the safety and efficacy of BioWorma® (Duddingtonia flagrans NCIMB 30336) when used as a zootechnical feed additive for all grazing animals. Duddingtonia flagrans belongs to a group of nematophagous fungi that physically entrap nematodes through an adhesive hyphal net. The additive contains the fungus in the form of chlamydospores and is intended to control pathogenic nematodes on pasture, with subsequent benefits for grazing animals. No conclusions could be drawn on the safety for the target species due to lack of data. ■■■■■ As it is not possible to exclude the presence of secondary metabolites (other than flagranones) produced during fermentation and their potential carry‐over into animal products, safety for the consumer could not be established. The Panel concluded that the additive is not irritant to skin and eyes but is irritant to the respiratory tract and a respiratory sensitiser. No conclusion could be drawn on its skin sensitisation potential. Since D. flagrans is a naturally inhabiting soil organism of world‐wide distribution, the Panel considered that use of an additive based on this organism does not pose a risk for the environment under the intended conditions of use. The strain under application reduced the number of parasitic nematodes on pasture to the benefit of grazing animals when used at the recommended application rate of 3 × 104 chlamydospores/kg bodyweight and day. [ABSTRACT FROM AUTHOR]

Copyright of Chinese Journal of Preventive Veterinary Medicine / Zhongguo Yufang Shouyi Xuebao is the property of Chinese Journal of Preventive Veterinary Medicine Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Duddingtonia flagrans is a nematophagous fungus which has shown promising results as a non-chemical parasitic control tool. The fungus disrupts the parasite's life cycle by trapping larvae in the environment through the networks generated from chlamydospores, thus preventing the reinfection of animals. One barrier to the development of a commercial product using this tool is the need to increase chlamydospore production in the laboratory for its administration to livestock. The purpose of this study was to evaluate the addition of mannitol to an enriched culture medium and the effect of adverse cultivation conditions on chlamydospore production. D. flagrans was cultivated on Petri dishes with corn agar for 4 weeks at 27 °C and 70% relative humidity (RH). Four groups were then formed, all with Sabouraud agar as a base, to which different growth inducers were added: GSA (glucose Sabouraud agar), GSA-MI (glucose Sabouraud agar + meso inositol), GSA-E (enriched glucose Sabouraud agar), and AE-M (enriched agar + mannitol). After 4 weeks, chlamydospores were recovered by washing the surface of each plate with distilled water and then quantified. The medium that yielded the highest amount of chlamydospores was subjected to different cultivation conditions: NC (normal conditions): 70% RH and 27 °C, AC (adverse conditions) 1: 20% RH and 40 °C, CA2: 60% RH and 27 °C, and CA3: 55% RH and 24 °C. It was determined that mannitol increases chlamydospore production (65x106 chlamydospores/plate), and when reducing humidity by 10% under cultivation conditions it resulted in an approximately 10% increase in chlamydospore production compared to the control group. These results suggest that the addition of polyols, as well as its cultivation under certain environmental conditions, can improve chlamydospore production on a laboratory scale. [Display omitted] • The production of chlamydospores in Duddigntonia flagrans is enhanceable by adding mannitol to the culture medium. • Adverse conditions in the cultivation of Duddigntonia flagr ans stimulate chlamydospore production. • Duddingtonia flagrans retains its nematophagous capacity following the addition of mannitol or the assessed adverse culture conditions. [ABSTRACT FROM AUTHOR]

Sustainable and profitable small ruminant production in the US is affected by infections with gastrointestinal nematodes (GIN), especially the blood sucking GIN, Haemonchus contortus. The overuse and misuse of available drug classes has led to multi-drug resistant GIN that pose significant challenges to parasite control on many farms. The objective of this study was to evaluate the effectiveness of a natural fungus (Duddingtonia flagrans; Bioworma, International Animal Health) in reducing GIN larval counts and other GIN indicators in hair sheep wethers. Eighteen St. Croix (n = 9) and Barbados Blackbelly (n = 9) wethers (227 ± 1.4 days of age and 29.7 ± 0.6 kg BW) were de-wormed (d 0) with a combination of levamisol (Prohibit; 8 mg/kg BW) moxidectin (Cydectin; 0.2 mg/kg BW) and albendazole (Valbazen; 7.5 mg/kg BW) prior to the start of feeding according to the manufacturer's recommendations for feeding BioWorma. At this time, lambs were separated into two treatment groups (n = 9/group), split into 3 replications per treatment group and placed on six pasture paddocks (0.06 ha; n = 3 per paddock) after accounting for breed, initial fecal egg count (FEC) and BW. Lambs were then fed daily either a grain supplement ration (corn and soybean meal) with Livamol with Bioworma (LIV) or without (CON) at 2% of their BW for 98 d. LIV was added to the ration based on total lamb BW/paddock. To evaluate the effect of LIV treatment, BW and body condition scores (BCS) were recorded every 2 wk for 98 d. Blood and fecal samples were also collected for determination of packed cell volume (PCV) and FEC. Pooled treatment group feces (d 0 - 98) were collected and cultured to determine GIN genera. A subset of animals/treatment (n = 3) will be harvested to determine abomasal worm counts. Data were analyzed using repeated measures in a mixed model, and FEC were log transformed before analysis. Following deworming (d 0), FEC were reduced by 100% by d 14. There was a mixed population of GIN at the start of the study (averaging 54%, 42%, 1.2% and 1.8% for H. contortus, Tricostrongylus spp., Oesphagostomum spp. and Nematodirus spp., respectively). LIV with Bioworma supplementation had no impact on BW, BCS, PCV or FEC in this study averaging 34.2 ± 0.3 kg, 2.5 ± 0.04, 34.7 ± 0.5% and 150.9 eggs per gram, respectively. Under the conditions of this study, Bioworma® supplementation had no influence on GIN indicators measured up to 100 d of grazing. This research will be continued during subsequent grazing seasons to determine the effect of continued supplementation on lamb parasite load and performance as well as pasture infestation levels. [ABSTRACT FROM AUTHOR]

A nematode trapping fungus, Duddingtonia flagrans (Df), fed to sheep is useful for biocontrol of gastrointestinal nematodes on pasture. The objectives were: 1) validate methods to determine viability of a commercial source of Df before beginning research studies, and 2) examine the interaction between Df and dietary coccidiostat (as decoquinate). Methods: Study 1: In Jan 2023, weaned Katahdin lambs (97.3 ± 1.2 d of age; 19.5 ± 1.3 kg BW; packed cell volume of 26.5 ± 1.4 %), naturally infected with predominantly Haemonchus contortus (89%) and mean fecal egg count (FEC) of 6,860 ± 1,535 eggs/g, were randomly assigned to: 1) no Df (-g)/(FEC-g)x100]. Study 2: In Aug 2023, 7 mo old anthelmintic-treated ram lambs (FEC < 50 egg/s; 51.6 ± 3.9 kg in BW) were fed grain supplement daily with decoquinate (Deccox; +C) or without (-C; n = 3/diet) on d -7 to 1, and, within diet, administered 3 g BioWorma/d in 6 gel capsules (+DF; n = 2/diet) or not (-DF; n = 1) on d -1 and -2. Fecal samples were collected on d 0 (2 g/plate + 300 L3 of H. contortus) and d 1 (6 g/plate + 1000 L3) and placed on water agar plates (n = 3/lamb) at 25°C. Trapping structures were visually assessed after 24, 48, and 144 h (6 d), and cultures Baermannized on d 7 for L3 recovery. Relative reduction was (...-DF-C-...+DF+C/...-DF-C)x100%. Data for variables collected one time were analyzed by Proc GLM (SAS), and for those collected serially, a Proc Mixed with repeated measures. A 2x2 factorial was used in Study 2 and included treatments, day and interaction in model. Results: Study 1: As expected, L3 recovery was reduced (P = 0.005) in DF lambs by 67-78% relative to control. Study 2: DF formed loops and traps around L3 by d 6 and reduced L3 recovery on both days (P < 0.001) without an interaction by decoquinate (P = 0.69). The L3 reduction relative to -DF-C was between 60.2-73.5%. The coccidiostat, decoquinate, can be added to the diet in the presence of BioWorma without antagonism. In conclusion, the in vitro studies allow detection of adverse issues with viability of Df and can reduce the number of animals needed for research studies. [ABSTRACT FROM AUTHOR]

Parasiticidal fungi have been used in several in vivo experiments in livestock farms worldwide, constituting an effective tool for the biocontrol of gastrointestinal parasites in grazing animals. In the first year of study, two groups of eight first-season pasturing ewe lambs infected by strongyles were dewormed with albendazole, and then, the test group received an oral dose of 106 chlamydospores of Mucor circinelloides and 106 Duddingtonia flagrans individually and thrice a week from mid-September to May (FS1), while the control group remained without fungi (CT1). In the second year, two new groups of first-season grazing ewe lambs were treated with ivermectin and subjected to the same experimental design (FS2 and CT2, respectively). The anthelmintic efficacy was 96.6% (CT1), 95.6% (FS1), 96.1% (CT2), and 95.1% (FS2). The counts of strongyle egg output increased in the control groups (CT1 and CT2) throughout the study and reached numbers higher than 600 eggs per gram of feces (EPG), while in FS1 and FS2, they were M. circinelloides and D. flagrans provides a helpful strategy for maintaining low levels of strongyle egg output in first-season grazing ewe lambs and improves their health status.

Plant parasitic nematodes, especially parasitic root-knot nematodes, are one of the most destructive plant pathogens worldwide. The control of plant root-knot nematodes is extremely challenging. Duddingtonia flagrans is a type of nematode-trapping fungi (NTF), which produces three-dimensional adhesive networks to trap nematodes. In this study, the pathogenicity and volatile organic compounds (VOCs) of the NTF D. flagrans against the plant root-knot nematode, Meloidogyne incognita, were investigated. The predatory process of D. flagrans trapping M. incognita was observed using scanning electron microscopy. Gas chromatography-mass spectrometry analysis of the VOCs from D. flagrans led to the identification of 52 metabolites, of which 11 main compounds were tested individually for their activity against M. incognita. Three compounds, cyclohexanamine, cyclohexanone, and cyclohexanol, were toxic to M. incognita. Furthermore, these three VOCs inhibited egg hatching of M. incognita. Cyclohexanamine showed the highest nematicidal activity, which can cause 97.93% mortality of M. incognita at 8.71 µM within 12 h. The number of hatched juveniles per egg mass after 3 days was just 8.44 when treated with 26.14 µM cyclohexanamine. This study is the first to demonstrate the nematicidal activity of VOCs produced by D. flagrans against M. incognita, which indicates that D. flagrans has the potential to biocontrol plant root-knot nematodes.

Abstract Duddingtonia flagrans has been tested as an alternative parasite control, but data from in vitro experiments based on in vivo calculations describing nematophagous fungi predation in nematodes are restricted. The objective of this work was to determine the efficacy of D. flagrans against sheep nematode larvae in vitro using in vivo calculations. Fecal samples were introduced to fungi in different concentrations: 0.0/control; 0.05; 0.1; 0.2; 0.4; 0.8; 1.6; 3.2; and 6.4 g corresponding, respectively, to 583.000; 1.166.000; 2.332.000; 4.664.000; 9.328.000; 18.656.000; 37.312.000 and 74.624.000 chlamydospores/kg of body weight. The material was incubated for 14 days, before the larvae recovery (Assay 1). Assay 2 was carried out with the doses of 0.00625; 0.0125; and 0.025 g. The results showed a negative correlation between fungal concentrations and larval numbers for both assays. The fungus demonstrated an efficacy above 89% in both assays. Thus, we consider that the data from in vitro studies based on in vivo calculations may optimize the fungi quantities for field experiments.

The objective of the present work was to evaluate the efficiency of Bioverm® fungal formulation (Duddingtonia flagrans—AC001) in controlling Haemonchus contortus and Strongyloides papillosus in sheep. In vitro predation tests were carried out in Petri dishes containing agar culture medium 2%. Four experimental groups were formed, with five replicates each: Group 1: 1 g of Bioverm® and 1000 third-stage larvae (L3) of H. contortus; Group 2: 1000 L3 of H. contortus; Group 3: 1 g of Bioverm® and 1000 L3 of S. papillosus; and Group 4: 1000 L3 of S. papillosus. In the in vivo tests, twelve 11-month-old sheep males positive for H. contortus were used. The animals were sorted in two groups (treatment and control), based on fecal egg counts (eggs per gram, EPG). Each group comprised six animals: treatment group—each animal received orally 100 g of Bioverm®; and control group—each animal received orally 100 g of rice. Subsequently, feces from these animals were collected at 12, 24, 36, 48, 60, 72, 84, and 96 h after Bioverm® administration. In vitro results demonstrate that D. flagrans kept its predatory activity with 91.5% of mean reduction percentage of L3. After the passage test, Bioverm® presented efficacy already after 12 h of its administration and kept similar results for 60 h. Bioverm® fungal formulation (D. flagrans—AC001) was efficient in reducing the population of H. contortus and S. papillosus under laboratory conditions in sheep feces. However, further studies are needed under natural conditions of ruminant grazing to prove the efficiency of this product. [ABSTRACT FROM AUTHOR]

Duddingtonia flagrans is a nematode-trapping fungus that has shown promising results as a tool to combat parasitic nematode infections in livestock. The fungus interrupts the parasitic lifecycle by trapping and killing larval stages on pasture to prevent re-infection of animals. One barrier to the fungus' commercial use is scaling up production of the fungus, and specifically of chlamydospores, which survive the digestive tract to grow in fecal pats on pasture, thus have potential as a feed through anthelmintic. The purpose of this study was to evaluate the effect of dehydration on sporulation of the fungus. Disks of Duddingtonia flagrans type strain (ATCC® 13423™) were grown on 17% cornmeal agar for 26 days at 30 °C, then split into three groups; dried quickly at 38 °C and 37% humidity over 48 h ("incubated"), dried more slowly at 24 °C and 55% humidity over 10 days ("air-dried"), or kept at 30 °C and sealed with parafilm to prevent loss of moisture as a control ("wet"). Half of each dried culture was resuspended in water, then heated to liquify and homogenized through vortexing. Spores were then counted in a Neubauer hematocytometer. Both the "air-dried" and "incubated" drying techniques yielded significantly more spores than the "wet" control (Welch's two sample t test p values of.0359 and.0411, respectively). The difference in average chlamydospores per milliliter was insignificant between the two drying techniques, although a visual representation of the data shows less spore count variability in the "air-dried" technique. [ABSTRACT FROM AUTHOR]

We describe the synthesis and a function of melanin in Duddingtonia flagrans, a nematode-trapping fungus. We tested various culture media treated with L-DOPA, glucose and tricyclazole on fungal growth and melanin distribution using infrared spectroscopy (IS), electron paramagnetic resonance (EPR) and transmission electron microscopy (TEM). In vitro rumen digestion was used to test the environmental stress and then to evaluate the capacity of this fungus to trap nematode larvae. The growth and melanization of the fungus after 21 days of incubation at 30°C were best in Sabouraud dextrose medium. IS indicated the presence of melanin in D. flagrans, with similar bands for commercial melanin used as a control, and assigned the values obtained by EPR (g of 2.0051 ± 0.0001) to the production of melanin by the fungus. TEM indicated that melanin was produced in melanosomes but was not totally inhibited by tricyclazole. Within the limits of experimental error, the predatory activity of fungus treated with tricyclazole was drastically affected after 27 h of in vitro anaerobic stress with rumen inoculum. The deposition of melanin particles on the fungal cell wall contributed to the maintenance of D. flagrans predatory abilities after in vitro anaerobic ruminal stress. [ABSTRACT FROM AUTHOR]

This study aimed to determine the effects of Duddingtonia flagrans contained in sodium alginate pellets on trichostrongylide larvae under different storage conditions and durations. The in vitro predatory activity of D. flagrans in pellets against trichostrongylide larvae in sheep faeces were assessed at 0, 1, 3, 6, 9, and 12 months after the pellet was stored under four different conditions (i.e. −20, 4°C, outdoors, and indoors). These results revealed that the numbers of larvae in faeces of sheep treated with pellets containing chlamydospores (treatment groups) were significantly lower than those in the control groups (without chlamydospores) for all trial months under four storage conditions for different durations (p <.05). The obtained reduction rates of the infective larvae (L3) in the four treatment groups ranged from 45.62% to 96.73% throughout the entire experiment. The overall mean L3 reduction percentages were 89.22% ± 3.74%, 88.97% ± 1.33%, 68.60% ± 14.31%, and 75.45% ± 13.18% for 4°C refrigeration, −20°C refrigeration, indoor, and outdoor conditions, respectively. The pellets stored under these storage conditions for a year were provided to sheep for ingestion (in vivo test), and the results showed that the number of recovered larvae in sheep faeces at 24 h after ingestion were significantly lower than that before ingestion. For in vivo test, the L3 reduction percentage in the faeces was 90.99% (−20°C), 74.81% (outdoor), 83.53% (4°C), and 65.60% (indoor). Under the four storage conditions, D. flagrans spores contained in the pellets can maintain their survival ability to a varying degree in a year. [ABSTRACT FROM AUTHOR]

• iTRAQ-based means was firstly used to analyze proteomic differences on D. flagrans. • 4244 proteins are detected, with hundreds of proteins are differential proteins. • The proteins from different predatory stages play key role in nematode-trapping. • Proteases are required for D.flagrans to catch and feed on nematodes. Duddingtonia flagrans , as a representative species of nematode-trapping fungi, has a strong environmental tolerance and nematode-trapping ability and is thought of as the most promising candidate for use as a biological agent. To clarify the proteomic differences during different predation periods and to explore the molecular background of the nematode-trapping mechanism, we carried out an iTRAQ (isobaric tags for relative and absolute quantitation)-based quantitative proteomic analysis for Duddingtonia flagrans during three predatory stages (0 h, 12 h, and 48 h). A total of 4244 proteins were detected; 474 of these showed differential protein abundance from 0 h to 12 h, while 119 showed differential protein abundance from 12 h to 48 h. The 474 proteins from 0 h to 12 h were primarily associated with catalytic activity, molecular binding function, transport activity, biological regulation, stress response, biolocation and carbon utilization, while the 119 proteins from 12 h to 48 h were involved in substance and energy metabolism. Further bioinformatics analysis showed that these proteins could be mapped to various pathways, eight of which were significantly enriched after mapping to KEGG pathways from 0 h to 12 h, and substance and energy metabolism were enriched from 12 h to 48 h. Interestingly, many of these differentially expressed proteins were involved in the significantly enriched pathways of ubiquitin-mediated proteolysis, endoplasmic reticulum protein processing, sphingolipid metabolism, adhesion processes, MAPK signaling pathway, AMPK signaling pathway, energy and carbon metabolism, peroxidase, and oxidative phosphorylation, including acid phosphatase, neutral ceramidase, sphingomyelin phosphodiesterase, tyrosinase, and serine protease. These findings not only deepen our understanding of the proteome during different predation periods in Duddingtonia flagrans but also provide a basis for screening and identification of predation-related proteins to reveal the biological processes of the fungus and its action on nematodes, thereby helping to elucidate the nematode-trapping mechanism of D. flagrans. [ABSTRACT FROM AUTHOR]

This study aims to investigate the molecular phylogenetic analysis, morphological variability, nematode‐capturing ability, and other biological properties of Chinese Duddingtonia flagrans isolates. We isolated 13 isolates of D. flagrans and found features that have never been reported before, such as two to three septa incluing club‐shaped conidia. Meanwhile, we conducted molecular phylogenetic analysis of the seven isolates and tested the radical growth of the isolates under different pH values, temperatures, and media. The capturing ability against infective larvae (L3) of Cooperia spp. in yak was detected in vitro. Finally, one isolate was selected for scanning electron microscopy (SEM) to investigate the trap formation process. The fungal sequence was obtained and submitted to GenBank (Accession no. KY288614.1, KU881774.1, KP257593.1, KY419119.1, MF488979.1, MF488980.1, and MF488981.1), and the tested isolates were identified as D. flagrans. Except for three isolates, the radial growth of the other isolates on 2% corn meal agar and 2% water agar exhibited faster growth than on other media. The fungus could not grow at 10 and 40°C but grew within 11 to 30°C. Moreover, it did not grow at pH 1–3 and 13–14, but instead at pH 4–12. In the in vitro experimental, L3s were reduced by 94.36%, 88.15%, and 91.04% for SDH035, DH055, and F088, respectively. SEM results showed that at 8 hr post addition of nematodes, some of the latter were captured. In the later stages of the interaction of the fungus with nematodes, a large number of chlamydospores were produced, especially on the predation trap. Results of the present study provided information about the molecular phylogenetic analysis, morphological variability, nematode‐capturing ability, and other biological properties of Chinese Arthrobotrys flagrans isolates before administering them for biocontrol. [ABSTRACT FROM AUTHOR]

Nematode-trapping fungi (NTF) are a large and diverse group of fungi, which may switch from a saprotrophic to a predatory livestyle if nematodes are present. Different fungi have developed different trapping devices, ranging from adhesive cells to constricting rings. After trapping, fungal hyphae penetrate the worm, secrete lytic enzymes and form a hyphal network inside the body. We sequenced the genome of Duddingtonia flagrans, a biotechnologically important NTF used to control nematode populations in fields. The 36.64 Mb genome encodes 9,927 putative proteins, among which are more than 638 predicted secreted proteins. Most secreted proteins are lytic enzymes, but more than 200 were classified as small secreted proteins (< 300 amino acids). 117 putative effector proteins were predicted, suggesting interkingdom communication during the colonization. As a first step to analyze the function of such proteins or other phenomena at the molecular level, we developed a transformation system, established the fluorescent proteins GFP and mCherry, adapted an assay to monitor protein secretion, and established gene-deletion protocols using homologous recombination or CRISPR/Cas9. One putative effector protein, PefB, was transcriptionally induced during the interaction. We show that the mature protein is able to be imported into nuclei in C. elegans cells. In addition, we studied trap formation and show that cell-to-cell communication is required for ring closure. The availability of the genome sequence and the establishment of many molecular tools will open new avenues to studying this biotechnologically relevant nematode-trapping fungus. [ABSTRACT FROM AUTHOR]

Cooperia, Haemonchus and Oesophagostomum are the genera of gastrointestinal parasitic nematodes most prevalent in cattle and constitute a serious problem in cattle breeding due to the impact they have on meat and milk production and the high costs of control measures. The objective of the present work was to evaluate the efficiency of Bioverm® (Duddingtonia flagrans) in the control of gastrointestinal parasitism of young cattle raised in the field, in the Central-West region of Brazil. The experiment was conducted on a farm located in the municipality of Jangada, MT, where 18 cattle, Nelore and Aberdeen Angus breeds, aged six to ten months, were randomly divided into two groups (treated group and control group) and distributed in paddocks of Brachiaria decumbens, naturally infested by larvae of gastrointestinal nematodes. The animals in the treated group received 1g of Bioverm® for each 10 kg of body weight, administered daily with commercial feed, throughout a period of six months. In the control group, each animal received 1 g of rice bran for each 10 kg of body weight, without Bioverm®, added to the feed. Stool and pasture samples were collected every two weeks. The treated group showed a significant reduction (p < 0.05) in values of eggs per gram of feces (EPG) and a significant gain of body weight (p < 0.05) when compared to the control group. The fungal formulation Bioverm® was effective in pasture decontamination and consequently in reducing the occurrence of reinfection by nematodes. The animals treated with Bioverm® showed a lower parasitic load and greater weight gain.

Gastro-intestinal nematodes (GIN) of sheep are one of major constraints in grazing production systems worldwide. Control is commonly achieved using anthelmintics, but global occurrence of anthelmintic resistance to different drugs and the emergence of multi-resistant GIN species seriously limit the efficiency of their use. Therefore, integrated parasite management is widely recommended, with nematophagous fungi as one of control tools. Duddingtonia flagrans is one of the most used species, with various effect of different isolates. In previously performed coproculture assay, we showed low efficacy of D. flagrans MUCL 9827 against infective larvae (L3) of sheep GIN. The aim of current experiment was to reevaluate its nematophagous potential, using the medium where direct interaction between the fungus and L3 could be observed. Nematophagous activity was tested on 2% water agar with addition of chloramphenicol on three series of plates seeded with 500 and 1000 chlamidospores and agar blocks with 7 days old mycelium. At Days 0 and 5, 500 L3 of sheep GIN were added to test the trapping activity. The cultures, including control plates with only L3, were incubated at 25°C for 10 days, followed by evaluation of their number and reduction percentage. Nematophagous activity of D. flagrans MUCL 9827 against L3 was clearly demonstrated. However, the overall efficacy was poor since trapping was observed only in one out of nine plates containing fungal material. Potential reasons for such poor performance of the isolate of fungal species, otherwise known as successful in trapping animal parasitic nematodes, are discussed.

Small ruminant production in the US is significantly impacted by infections with gastrointestinal nematodes (GIN), especially the blood sucking GIN, Haemonchus contortus. Unfortunately, the indiscriminate use of available drug classes has led to multi-drug resistant GIN that pose significant challenges to parasite control on many farms. The objective of this study was to evaluate the effectiveness of a natural fungus, Duddingtonia flagrans (Bioworma, International Animal Health) in reducing GIN loads in lactating meat does. Thirty eight late gestating Spanish and Myotonic does were dewormed (day 0) approximately 2 weeks before to kidding with a combination of levamisol (Prohibit; 12 mg/kg BW) and moxidectin (Cydectin; 0.4 mg/kg BW) before the start of feeding BioWorma according to the manufacturer's recommendations. At this time, does were also allocated into two treatment groups (n = 19/group), split into 3 replications per treatment and placed on six pasture paddocks (n = 6/7 per paddock). Does were then fed either a corn and soybean meal supplement at 1.5% of their BW with (BIO) or without (CON) Bioworma daily until weaning and hay was offered throughout the study. Bioworma was added to the ration based on the manufacturer's recommended dose of 0.066 g/kg BW and on the BW of the heaviest doe. To evaluate the effect of Bioworma treatment, BW, body condition score (BCS), and FAMACHA scores were recorded every 2 weeks for 98 days. Blood and fecal samples were also collected for determination of packed cell volume (PCV) and fecal egg counts (FEC). Pooled (d 28) or pooled treatment group feces (d 42, 56, 70, 84 and 98) were also collected and cultured to determine GIN genera. If blood PCV decreased to below 19%, does were dewormed and removed from the study (n = 2 BIO; n = 2 CON). Data were analyzed using repeated measures in a mixed model, and FEC were log transformed before analysis. Following deworming (d 0), FEC were reduced by 97% by d4. There was a mixed population of GIN throughout the study (averaging 70.3%,7.7%, and2.0% for H. contortus, Tricostrongylus spp., and Oesphagostomum spp., respectively). Bioworma supplementation had no impact on BW, BCS, FAMACHA scores, nor PCV averaging 38.8 ± 0.5 kg, 2.3 ± 0.03, 2.2 ± 0.02, and 29.3 ± 0.3%, respectively. There was also no effect of treatment on FEC (averaging 1,067±254 and 1,107±144 and 987±282 and 847±163 eggs per gram for BIO and CON does on days 0 and 98, respectively. Bioworma supplementation in a highly susceptible group of lactating does, had no influence on GIN indicators. Additional research is needed to confirm the efficacy of Duddingtoni flagrans in controlling GIN and how best to incorporate in current on-farm parasite control strategies. [ABSTRACT FROM AUTHOR]

A 14-d study was undertaken to test the acute toxicity of a new preparation Vetom 21.77 based on the predacious fungus Duddingtonia flagrans. A total of 40 healthy 5-day-old broiler chickens (Hubbard F15, 100 ± 5 g), that had previously gone through a required 5-days adaptation to the environment, were orally dosed with the drug for 5 consecutive days at different doses, after which their health status was assessed daily up to the end of the experiment. According to the results, no substantial changes in the physiological state of the chickens were detected during the experiment. Internal organs weighing revealed no statistically significant differences between the groups, though weight coefficient values of internal organs of treated chickens slightly exceeded those of the control group. Some haematological parameters were significantly higher in the treatment group, without going beyond reference ranges. All chickens used in the experiment survived the study. The preparation has not produced any toxic effect even at a higher dose (4000 µL/kg bw/day). It is concluded that Vetom 21.77 pertains to preparations of IV toxicity class. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • The Duddingtonia flagrans dose/response in zebu calves was assessed. • Three doses: 0.250 × 106; 0.5 × 106 and 1 × 106 per kg/BW were assessed. • Low, medium and high doses reduced 58%, 73% and 73.5% the faecal larvae. • Cooperia spp. and H. contortus were the species identified. • The medium dose was enough to substantially reduce the faecal larvae population. Abstract This research assessed the dose/response to Duddingtonia flagrans chlamydospores (Df -C) administered to calves naturally infected with gastrointestinal nematodes (GINs), and its effect in reducing the infective larvae (L 3) population in faeces in a farm in the Mexican tropics. Forty zebu calves, between 6 and 12 months of age, were randomly distributed into four groups of 10 calves. One control and three groups treated with different oral doses of Df -C based on their body weight (BW) were established as follows: group 1 (control); group 2, 0.250 × 106 Df -C per kg/BW; group 3, 0.5 × 106 Df -C per kg/BW and group 4, 1 × 106 Df -C per kg/BW. The fungal doses were administered daily for 10 days. Every group was confined to individual pens, and they received a nutritional regime based on Buffel grass, concentrated supplement and water ad libitum. Every third day, starting one week before treatments, faeces were taken from the rectum of each animal to determine the number of eggs per g of faeces (epg) through the McMaster technique. Four coprocultures of 20 g each from each individual faecal sample were prepared and incubated for 14 days. The efficacy of the treatments was based on the mean of the GIN L 3 recovered from coprocultures of the different groups. Data were analysed using a completely randomized design through an ANOVA analysis, followed by a Duncan multiple range test. The efficacy of treatments was expressed as the larval reduction rate. High variation in the epg in the different groups along the experiment was recorded. The reduction in the GIN L 3 population was observed from the 4 to 11 day post-treatment in the three assessed doses. Results in group 2 (lowest fungal dose), showed 88.5, 57.6, 55.9 and 30% (58% overall reductions) in the GIN L 3 in the faeces of animals 4, 7, 9 and 11 days post-treatment, respectively. In group 3 (medium fungal dose), 95.8, 80.4, 63.4 and 52.7% GIN L 3 reductions (73% overall reduction) were recorded, respectively. At the highest Df -C dose used (1 × 106 per kg/BW), the results were 88.9, 78.0, 59.3 and 67.3% (73.5% overall reduction), respectively (p < 0.05). The species of identified nematodes through L 3 morphometric and molecular taxonomy were Cooperia spp. and H. contortus. From the three Df -C assessed doses, the medium dose (0.5 × 106 Df -C per kg/BW) was sufficient to substantially reduce the GIN L 3 in zebu calves maintained under conditions in the Mexican tropics. [ABSTRACT FROM AUTHOR]

Abstract Duddingtonia flagrans is a natural strain of Nematophagous-Fungi isolated around the world. It has demonstrated efficacy and ease of use in laboratory as well as in field conditions. The fungus contributes to the prophylactic control of the worms by reducing the number of L 3 on pasture. The aims of this study were to test and analyze the predatory effect of D. flagrans under sunny and shaded conditions on the L 3 in the faeces, and to verify the reduction of translation to pasture during summer and winter seasons. Faecal Mass Units (FMUs) were assigned to two treated groups (groups treated with D. flagrans chlamydospores, TG) and two untreated groups (without D. flagrans chlamydospores, UG), in summer and winter, under sunny and shaded conditions. FMUs and herbage samples were taken for parasitological workup. Predatory activity of D. flagrans was evident under both conditions for the summer experiment but was not manifest for the winter experiment. In summer, an interaction between sunny and shaded conditions and predatory activity of D. flagrans was found. Environmental conditions on predatory activity should be considered when designing strategies for the implementation of D. flagrans in grazing systems to smooth the infectivity curve of L 3. Graphical abstract Image Highlights • The aim was to test Duddingtonia flagrans under different environmental conditions. • Predatory activity of Duddingtonia flagrans was evident in summer. • Predatory activity of Duddingtonia flagrans was not manifest in winter. • Predatory activity of D. flagrans was affected by the environment conditions. [ABSTRACT FROM AUTHOR]