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Item Avaliação in vitro do fungo predador de nematoides Duddingtonia flagrans sobre larvas infectantes de ciatostomíneos de equinos ( Nematoda: Cyathostominae)(Revista Brasileira de Parasitologia Veterinária, 2009-12) Braga, Fabio R.; Araújo, Jackson V.; Araujo, Juliana M.; Silva, André R.; Carvalho, Rogério O.; Campos, Artur K.A capacidade predatória de um isolado de fungo predador de nematoides Duddingtonia flagrans (AC001) sobre larvas infectantes de ciatostomíneos foi avaliada em condições laboratoriais em ensaio experimental em meio ágar-água 2% (AA 2%). Houve redução significativa (p < 0,01) de 93,64% na média de larvas infectantes de ciatostomíneos recuperadas do meio AA2%, ao final de sete dias. Os resultados desse ensaio evidenciam que o isolado fúngico AC001 poderia ser utilizado no controle biológico de ciatostomíneos de equinos.Item Nematicide activity of microfungi (Orbiliales, Orbiliaceae) after transit through gastrointenstinal tract of “Gallus gallus domesticus”(Revista Brasileira de Saúde e Produção Animal, 2017-01) Silva, Manoel Eduardo da; Silveira, Wendeo Ferreira da; Braga, Fábio Ribeiro; Araújo, Jackson Victor deParasites are common in intensive or organics systems destined for chickens, which is more conducive to the emergence of gastrointestinal parasites, favored by direct contact with soil and other organisms. The growing demand for animal protein stimulates an expansion of production systems, increasing the stocking density. Outdoor poultry breeding systems (organic or not) that enable lower population density and higher animal welfare does not exclude these animals the presence of environmental pathogens. The control of gastrointestinal helminthosis in non-organic intensive and extensive systems is accomplished by administering anthelmintics with high cost and results unsatisfactory due to the misuse of drugs with consequent selection parasite strains resistant to chemical bases. This problem stimulate research into alternative control measures. Nematophagous fungi are used by its enzymatic action in controlled conditions and how environmental biocontrolers of larvae of gastrointestinal nematodes of livestock. This study evaluated the capacity of conidia/chlamydospores of nematophagous fungi as Duddingtonia flagrans (AC001 and CG722) and Monacrosporium thaumasium (NF34A) for cross the gastrointestinal tract of domestic chickens (Gallus gallus domesticus), and yours germination after traffic and predatory activity “in vitro” on larvae of Panagrellus spp. Fungi conidia/chlamydospores was identified in feces of chickens at times of 6, 12 and 24 hours after administration and spores viability was found after observing the germination, mycelial growth, followed by production of traps, capture and death of Panagrellus spp larvae in feces. Fungi Nematophagous are alternative control measures, efficient and innovative technology for the biological control of helminth parasites of chickens.Item Control of bovine gastrointestinal nematode parasites using pellets of the nematode-trapping fungus Monacrosporium thaumasium(Ciência Rural, 2004-03) Araújo, Jackson Victor de; Guimarães, Marcos Pezzi; Campos, Artur Kanadani; Sá, Nilo Chaves de; Sarti, Priscilla; Assis, Rafaela Carolina LopesThe viability of a formulation of the fungus Monacrosporium thaumasium associated with ivermectin was evaluated for the biological control of bovine gastrointestinal nematode parasites. Four groups of five calves each were placed in pastures with a stocking rate of 1.6 animal/hectare. In group 1 (control), the calves did not receive any treatment. In group 2, each animal received 20g of pellets of M. thaumasium orally twice a week during a six-month period that began with the onset of the rainy season (October 23, 2000). In group 3, each animal received 20g of pellets of M. thaumasium orally twice a week during the same period as 2, as well as two strategic treatments with ivermectin (200 mcg/kg) on May 10, 2001 and July 5, 2001. In group 4, the animals were treated with ivermectin alone as described for group 3. EPG counts for group 1 were significantly greater (P< 0.01) than those for groups 2 and 3 and the difference at the end of the study period was near 100%. The EPGs of group 4 animals remained high until the first strategic treatment with ivermectin. Values for groups 1 and 4 differed significantly (P< 0.05) from those of groups 2 and 3 from December 2000 onwards. It was concluded that the use of this dose and periodicity of application of M. thaumasium pellets makes the application of anthelminthic treatments unnecessary.Item Fungi predatory activity on embryonated Toxocara canis eggs inoculated in domestic chickens (Gallus gallus domesticus) and destruction of second stage larvae(Parasitology Research, 2015-09) Araújo, Jackson Victor de; Fonseca, Leandro Abreu da; Hiura, Emy; Lopes, Aline del Carmen Garcia; Paz, Jeanne Saraiva da; Gava, Maylla Garschagen; Flecher, Mayra Cunha; Colares, Manuela; Soares, Filippe Elias de Freitas; Lacerda, Tracy; Braga, Fabio RibeiroThe objective of this study was to evaluate the infectivity of Toxocara canis eggs after interacting with isolated nematophagous fungi of the species Duddingtonia flagrans (AC001) and Pochonia chlamydosporia (VC4), and test the predatory activity of the isolated AC001 on T. canis second stage larvae after 7 days of interaction. In assay A, 5000 embryonated T. canis eggs previously in contact with the AC001 and VC4 isolated for 10 days were inoculated into domestic chickens (Gallus gallus domesticus), and then these animals were necropsied to collect material (digested liver, intestine, muscles and lungs) at 3-, 7-, 14-, and 21-day intervals after inoculation. In assay A, the results demonstrated that the prior interaction of the eggs with isolated AC001 and VC4 decreases the amount of larvae found in the collected organs. Difference (p < 0.01) was observed in the medium larvae counts recovered from liver, lung, intestine, and muscle of animals in the treated groups when compared to the animals in the control group. At the end of assay A, a percentage reduction of 87.1 % (AC001) and 84.5 % (VC4) respectively was recorded. In the result of assay B, the isolated AC001 showed differences (p < 0.01) compared to the control group, with a reduction of 53.4 % in the recovery of L2. Through these results, it is justified to mention that prior interaction of embryonated T. canis eggs with the tested fungal isolates were efficient in reducing the development and migration of this parasite, in addition to the first report of proven predatory activity on L2.Item Application of a formulation of the nematophagous fungus Duddingtonia flagrans in the control of cattle gastrointestinal nematodiosis(World Journal of Microbiology and Biotechnology, 2007-09) Dias, Anderson S.; Araújo, Jackson V.; Campos, Artur K.; Braga, Fabio R.; Fonseca, Thiago A.The viability of a formulation of Duddingtonia flagrans was assessed in the control of parasite gastrointestinal nematodes of cattle. Two groups (A and B) of eight crossbred Holstein × Zebu cattle, approximately one year old, were placed in Brachiaria decumbens pasture. Each animal in group B (treated) received orally 20 g sodium alginate pellets containing mycelial mass of the D. flagrans fungus, while the animals in the group A (control) received pellets without fungus for seven months, starting in March 2005. The egg per gram of feces counting the gastrointestinal nematodes showed a difference (P < 0.05) in the treated group in June, July and August, with reductions of 58% (June), 47% (July) and 51% (August) compared to the control group. The infective larvae recovered in the pastures collected up to 20 cm from distance of the fecal dung in group B differed (P < 0.01) from the larvae recovered in group A. At the end of the experimental period, the animals in group B presented a greater weight gain (P < 0.01) compared to the untreated group (A). The treatment of cattle with pellets containing the D. flagrans nematophagous fungus, at the dose and duration used was effective in controlling the infective larvae of gastrointestinal nematodes of cattle.Item Reduction of bovine strongilides in naturally contaminated pastures in the southeast region of Brazil(Experimental Parasitology, 2018-11) Oliveira, Isabela de Castro; Vieira, Ítalo Stoupa; Carvalho, Lorendane Millena de; Campos, Artur Kanadani; Freitas, Samuel Galvão; Araujo, Juliana Milani de; Braga, Fábio Ribeiro; Araújo, Jackson Victor deBiological control through the use of nematophagous fungi is a sustainable alternative for combatting helminthes in domestic animals and allows a reduction in the use of anthelmintics. The objective of this research was to evaluate the efficacy of the Arthrobotrys cladodes var macroides fungus in a pelleted formulation, based on sodium alginate and administered twice a week orally, as an alternative for the biological control of nematodes in field-grown young cattle. The experiment was conducted in a farm located in the municipality of Viçosa, MG, where 12 cattle, seven to nine months old, were allocated in two groups (treated group and control group) and distributed in pickets of Brachiaria decumbens, naturally infested with nematode larvae. The animals in the treated group received 1g of sodium alginate matrix pellets for every 10 kg of animal live weight, containing the nematophagous fungus Arthrobotrys cladodes var macroides and administered twice a week in conjunction with commercial feed. In the control group, each animal received 1 g of pellets for every 10 kg of animal live weight, without fungal mycelium added to the feed. Samples of feces and pastures were collected fortnightly for 12 months. The results showed that the most prevalent nematode genera in the coprocultures were Haemonchus sp., Cooperia sp. and Oesophagostomum sp., reflecting the results found in forage. The pasture that contained the animals that received feed with the fungus presented a reduction of 59% and 52% of larvae recovered at distances of 20 cm and 40 cm from the fecal pats, respectively. The mean number of eggs per gram of feces each month and animal body weight did not differ (p > 0.05) between the treated and control groups. Stool and soil samples from both groups were colonized by A. cladodes fungus and other fungi. Administration of Arthrobotrys cladodes var macroides mycelium by means of a sodium alginate matrix twice weekly reduced larval infestation of the surrounding pasture, indicating that this fungus may be a promising biological control of infecting forms of nematodes present in the environment.Item Using the fungus Arthrobotrys cladodes var. macroides as a sustainable strategy to reduce numbers of infective larvae of bovine gastrointestinal parasitic nematodes(Journal of Invertebrate Pathology, 2018-10) Oliveira, Isabela de Castro; Carvalho, Lorendane Millena de; Vieira, Ítalo Stoupa; Campos, Artur Kanadani; Freitas, Samuel Galvão; Araujo, Juliana Milani de; Braga, Fábio Ribeiro; Araújo, Jackson Victor deResearch in the area of sanitation in ruminant production has focused on discovery of potential agents for biological control of helminths with nematophagous fungi and has provided evidence of success. The antagonistic potential of the fungus Arthrobotrys cladodes var. macroides on infective larvae of bovine gastrointestinal parasitic nematodes was evaluated by scanning electron microscopy. Additionally, an in vivo test of the resistance to digestive processes and viability of the fungus was carried out using a formulation based on sodium alginate administered orally in cattle. Production of conidia and chlamydospores was high. In in vitro tests, the number of infective nematode larvae was reduced 68.7% by the fungus in the treated group compared to the control group. The interaction between the fungus and the nematodes was confirmed by scanning electron microscopy. Plates containing fecal samples collected after oral administration of 100 g of pellets containing the A. cladodes fungus showed that the fungus survived passage through the gastrointestinal tract of ruminants, grew on agar, formed traps and preyed on L3 larvae of gastrointestinal parasites. The results of the present study provide a new opportunity for alternative, environmentally safe control of ruminant nematodes.Item Application of a formulation of the nematophagous fungus Duddingtoniaflagrans in the control of cattle gastrointestinal nematodiosis(World Journal of Microbiology and Biotechnology, 2007-02-18) Dias, Anderson S.; Araujo, Jackson V.; Campos, Artur K.; Braga, Fabio R.; Fonseca, Thiago A.The viability of a formulation of Duddingtonia flagrans was assessed in the control of parasite gastrointestinal nematodes of cattle. Two groups (A and B) of eight crossbred Holstein × Zebu cattle, approximately one year old, were placed in Brachiaria decumbens pasture. Each animal in group B (treated) received orally 20 g sodium alginate pellets containing mycelial mass of the D. flagrans fungus, while the animals in the group A (control) received pellets without fungus for seven months, starting in March 2005. The egg per gram of feces counting the gastrointestinal nematodes showed a difference (P < 0.05) in the treated group in June, July and August, with reductions of 58% (June), 47% (July) and 51% (August) compared to the control group. The infective larvae recovered in the pastures collected up to 20 cm from distance of the fecal dung in group B differed (P < 0.01) from the larvae recovered in group A. At the end of the experimental period, the animals in group B presented a greater weight gain (P < 0.01) compared to the untreated group (A). The treatment of cattle with pellets containing the D. flagrans nematophagous fungus, at the dose and duration used was effective in controlling the infective larvae of gastrointestinal nematodes of cattle.Item In vitro evaluation of the action of the nematophagous fungi Duddingtonia flagrans, Monacrosporium sinense and Pochonia chlamydosporia on Fasciola hepatica eggs(World Journal of Microbiology and Biotechnology, 2008-01-06) Braga, F. R.; Araújo, J. V.; Campos, A. K.; Araújo, J. M.; Carvalho, R. O.; Silva, A. R.; Tavela, A. O.This work evaluated the in vitro action of four isolates of the nematophagous fungi Duddingtonia flagrans (AC001), Monacrosporium sinense (SF53) and Pochonia chlamydosporia (VC1 and VC4) on eggs of Fasciola hepatica. The eggs were plated on 2% water-agar with the grown isolates and control without fungus. After 7, 14 and 21 days, the eggs were removed and classified according to the following parameters: effect type 1, lytic effect with no morphological damage to eggshells; type 2, lytic effect with morphological changes in eggshells and embryos; and type 3, lytic effect with morphological changes in embryos and eggshells, with hyphal penetration and internal egg colonization. Pochonia chlamydosporia showed ovicidal activity on F. hepatica eggs in the studied intervals of the type-3 effect, of 12.8% (VC1) and 16.5% (VC4); 14.4% (VC1) and 18.7% (VC4), 20.1% (VC1) and 21.5 % (VC4), over 7, 14 and 21 days respectively. No statistical difference was found (P > 0.01) among the isolates VC1 and VC4 for effects type 1, 2 and 3 during the studied intervals. Duddingtonia flagrans (AC001) and Monacrosporium sinense fungi only showed effect type 1, with no significant difference between them, with the following results: 60.1% (AC001) and 57.5% (SF53); 62.3% (AC001) and 62.0% (SF53); 66.5% (AC001) and 73.4% (SF53), over 7, 14 and 21 days respectively. Pochonia chlamydosporia fungi negatively influenced the in vitro F. hepatica viability. Therefore it can be considered as a potential biological control agent for this helminth.Item Predation of Ancylostoma spp. dog infective larvae by nematophagous fungi in different conidial concentrations(Veterinary Parasitology, 2009-05-12) Maciel, A. S.; Araújo, J. V.; Campos, A. K.; Lopes, E. A.; Freitas, L. G.In the present work, it was evaluated the in vitro effect of 12 isolates from the fungal species Arthrobotrys, Duddingtonia, Nematoctonus and Monacrosporium genera in different conidial concentrations on the capture of Ancylostoma spp. dog infective larvae (L3), on 2% water-agar medium at 25 °C, at the end of a period of 7 days. The concentrations used for each nematophagous fungus were 1000, 5000, 10,000, 15,000 and 20,000 conidia/Petri dish plated with 1000 Ancylostoma spp. L3. All nematode-trapping fungi isolates tested reduced the averages of the uncaptured Ancylostoma spp. L3 recovered, with the increase of the fungal inoculum concentration, in comparison to the fungus-free control (p < 0.05). The adhesive network producing species were better predators than the constricting ring or adhesive knob producing species. Duddingtonia flagrans (Isolate CG768) was the most effective, reducing the averages of the uncaptured Ancylostoma spp. L3 recovered in 92.8%, 96.3%, 97.5%, 98.3% and 98.9%, respectively in five fungal inoculum concentrations established. Other effective nematophagous fungi were Arthrobotrys robusta (Isolate I31), which reduced the averages of the uncaptured Ancylostoma spp. L3 recovered in 85.4%, 88.3%, 90.7%, 92.5% and 95.2%, and Arthrobotrys oligospora (Isolate A183), with reductions of 66.6%, 79.8%, 86.8%, 89.5% and 90.8%, respectively for both, in the five fungal inoculum concentrations established. No difference was found between Isolates A183 and I31 in the conidial concentrations of 15,000/Petri dish. Nematoctonus robustus (Isolate D1) and Arthrobotrys bronchophaga (Isolate AB) had the smallest percentages of reduction among the tested isolates and showed the lowest predacious activity. The Isolates CG768, I31 and A183 were considered potential biological control agents of Ancylostoma spp. dog free-living stages, being directly influenced by the fungal inoculum concentration.