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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 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 Atividade predatória, crescimento radial e esporulação de fungos predadores de nematóides Monacrosporium spp, submetidos à criopreservação(Ciência Rural, 2004-03) Campos, Artur Kanadani; Mota, Marcelo de Andrade; Araújo, Jackson Victor de; Cecon, Paulo RobertoTestes in vitro foram realizados para avaliar o efeito da criopreservação em nitrogênio líquido com e sem adição de crioprotetores (DMSO ou glicerol), na atividade predatória sobre larvas infectantes de Cooperia sp e Haemonchus sp, crescimento radial e produção de conídios de dois isolados de fungos predadores de nematóides (Monacrosporium sinense e Monacrosporium appendiculatum). A capacidade predatória dos fungos sobre larvas infectantes de Cooperia sp e Haemonchus sp dos fungos previamente submetidos aos diferentes métodos de preservação não foi afetada. O crescimento radial dos fungos criopreservados com glicerol 10% foi mais expressivo(p<0,05), quando comparado ao apresentado pelos fungos congelados com DMSO 10 % ou água. A produção de esporos foi maior (p< 0,05) no fungo M. appendiculatum preservado a 4ºC em geladeira.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.Item Ovicidal effect of nematophagous fungi on Taenia taeniaeformis eggs(World Journal of Microbiology and Biotechnology, 2009-03) Braga, F. R.; Araújo, J. V.; Carvalho, R. O.; Silva, A. R.; Araujo, J. M.; Tavela, A. O.; Costa, P. R. S.; Campos, A. K.This work evaluated the ovicidal effect of the nematophagous fungi Monacrosporium sinense (SF53), Monacrosporium thaumasium (NF34) and Pochonia chlamydosporia (VC1) on Taenia taeniaeformis eggs in laboratory conditions. T. taeniaeformis eggs were plated on 2% water-agar with the grown isolates and control without fungus and examined at seven and fourteen days post-inoculation. At the end of the experiment, P. chlamydosporia showed ovicidal activity (P < 0.01) on T. taeniaeformis eggs unlike the other two species, mainly for internal egg colonization with percentage results of 32.2–54.0% at 7th and 14th day, respectively. The other fungi only showed lytic effect without morphological damage to eggshell. Results demonstrated that P. chlamydosporia was in vitro effective against Taenia taeniaeformis eggs unlike the other fungi. In this way, the use of P. chlamydosporia is suggested as a potential biological control agent for eggs of this cestode.Item Activity of the nematophagous fungi Pochonia chlamydosporia, Duddingtonia flagrans and Monacrosporium thaumasium on egg capsules of Dipylidium caninum(Veterinary Parasitology, 2009-12-03) Araujo, Juliana Milani; Araújo, Jackson Victor de; Braga, Fabio Ribeiro; Carvalho, Rogério Oliva; Ferreira, Sebastião RodrigoNematophagous fungi are potential biological control agents of helminths. The in vitro ovicidal effect of four isolates of the nematophagous fungi Pochonia chlamydosporia (VC1 and VC4), Duddingtonia flagrans (AC001) and Monacrosporium thaumasium (NF34) was evaluated on egg capsules of Dipylidium caninum, a cestode parasite of dogs, cats and humans. One thousand egg capsules of D. caninum were plated on 2% water-agar with the grown isolates and control without fungus. The ovicidal activity of these fungi was evaluated 5, 10 and 15 days after incubation. Only P. chlamydosporia showed ovicidal activity (p < 0.05) on D. caninum egg capsules, of 19.6% (VC1) and 20% (VC4) on the 5th day; 44.2% (VC1) and 31.5% (VC4) on the 10th day; and 49.2% (VC1) and 41.9% (VC4) on the 15th day. D. flagrans and M. thaumasium caused no morphological damage to egg capsules. The results demonstrated that P. chlamydosporia was in vitro effective against capsules and eggs of D. caninum, and can be considered as a potential biological control agent for this helminth.Item Biological control of Ancylostomosis in dogs using the nematode-trapping fungus Monacrosporium thaumasium in southeastern Brazil(Veterinary Parasitology, 2009-06-16) Carvalho, R.O.; Araújo, J.V.; Braga, F.R.; Araujo, J.M.; Silva, A.R.; Frassy, L.N.; Alves, C.D.F.; Ferreira, S.R.Parasitic nematodes Ancylostoma caninum and Ancylostoma braziliense affect dogs and cats and have great medical and veterinary importance for their high prevalence, zoonotic potential, cosmopolitan characteristic and soil contamination by eggs and larvae. In order to evaluate the efficiency of the nematophagous fungus Monacrosporium thaumasium (isolate NF34a) in the biological control of dog hookworm, 12 adult animals, average weight between 7 and 19 kg, were separated into groups and kept in 2 different kennels: control group (without fungus) and a group treated with 0.5 g of fungal mycelium per kilogram of body weight. The animals were treated and feces samples were collected for egg count (eggs per gram of feces—EPG) and coprocultures during six months, twice a week. Every 15 days soil samples were collected from each group and examined for infective larvae (L3) in the period between March and September 2008. From April onwards, EPG and coproculture recordings in the treated group were lower than the control group (p < 0.05). Linear regression coefficients for the control group were −30.79 and −160.79 for coproculture and EPG means, respectively. The linear regression coefficients for the treated group were −5.64 and −67.64 for EPG and coproculture means, respectively. Larvae were detected in the soil throughout the experimental period. From June to the end of the experiment (September), means of L3 recovered from the kennel soil of the control group were higher than the means of the kennel soil of the treated group (p > 0.05). The regression coefficient was higher for the treated group (−5.36) than the control group (−1.14), confirming the action of M. thaumasium against larvae in the soil. M. thaumasium can be therefore considered as an alternative environmental control of Ancylostoma spp. in dogs.Item Predatory activity of Pochonia chlamydosporia fungus on Toxocara (syn. Neoascaris) vitulorum eggs(Tropical Animal Health and Production, 2009-08-22) Braga, Fabio R.; Ferreira, Sebastião R.; Araújo, Jackson V.; Araujo, Juliana M.; Silva, André R.; Carvalho, Rogério O.; Campos, Artur K.; Freitas, Leandro G.Toxocara (Neoascaris) vitulorum is a gastrointestinal nematode parasite of young ruminants, responsible for high mortality rates in parasitized cattle and buffalo calves. The objective of this work was to compare the predatory capacity under laboratory conditions of four fungal isolates of the nematophagous fungus Pochonia chlamydosporia (VC1, VC4, VC5 and VC12) on T. vitulorum eggs in 2% water-agar (2% WA). T. vitulorum eggs were plated on 2% WA Petri dishes which contained cultured fungal isolates and control plates without fungi. After 10 and 15 days one hundred eggs were removed and classified according to the following parameters: type 1, biochemical and physiological effect without morphological damage to the eggshell, type 2, lytic effect with morphological alteration of the eggshell and embryo and type 3, lytic effect with morphological alteration of eggshell and embryo in addition to hyphal penetration and internal egg colonization. The fungal isolates were effective in the destruction of T. vitulorum eggs presenting the type 3 effect at 10 and 15 days after contact with the fungus. No nematophagous fungi were observed in the control group during the experiment. There was no variation in the predatory capacity of the fungal isolates (P > 0.01) at the intervals of 10 and 15 days. These results indicate that P. chlamydosporia (VC1, VC4, VC5 and VC12) negatively influenced the development of T. vitulorum eggs and can be considered a potential candidate for the biological control of nematodes.Item Predatory activity of nematophagous fungi on infective larvae of Ancylostoma sp.: evaluation in vitro and after passing through the gastrointestinal tract of dogs(Journal of Helminthology, 2009-09-01) Carvalho, R.O.; Araújo, J.V.; Braga, F.R.; Araujo, J.M.; Silva, A.R.; Tavela, A.O.The predatory capacity of nematophagous fungi Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34a), M. appendiculatum (CGI), M. sinense (SF53), Arthrobotrys conoides (I-40), A. cladodes (CG719) and A. robusta (I-31) on infective Ancylostoma sp. larvae (L3) was evaluated. Compared with the control without fungi there was a significant reduction (P < 0.05) of 87.02%, 82.74%, 47.93%, 60.49%, 76.89%, 71.33% and 86.02% in the mean number of Ancylostoma sp. (L3) recovered from treatments with the isolates AC001, NF34a, CGI, SF53, I-40, CG719 and I-31, respectively. Isolates AC001, I-31 and NF34a were more effective in capturing L3 during the in vitro assay. Isolates were then in vivo evaluated for the capacity to remain viable after passing through the gastrointestinal tract of dogs, while still maintaining their predatory activity against L3. Fungal isolates survived the passage and showed efficient predation 48 h after fungal administration to the dogs (P < 0.05). After this time, only the isolate NF34a remained effective up to 96 h after administration (P < 0.05). Monacrosporium thaumasium, D. flagrans and A. robusta are potential biological control agents of Ancylostoma sp. in dogs.Item Interaction and ovicidal activity of nematophagous fungus Pochonia chlamydosporia on Taenia saginata eggs(Experimental Parasitology, 2008-12-25) Araújo, Juliana M.; Araújo, Jackson V.; Braga, Fabio R.; Carvalho, Rogério O.; Silva, André R.; Campos, Artur K.The ovicidal activity of the nematophagous fungi Pochonia chlamydosporia (isolates VC1 and VC4), Duddingtonia flagrans (isolate AC001) and Monacrosporium thaumasium (isolate NF34) on Taenia saginata eggs was evaluated under laboratory conditions. T. saginata eggs were plated on 2% water-agar with fungal isolates and controls without fungus and examined after 5, 10 and 15 days. At the end of the experiment P. chlamydosporia showed ovicidal activity against T. saginata eggs (p < 0.05), mainly for internal egg colonization with results of 12.8% (VC1) and 2.2% (VC4); 18.1% (VC1) and 7.0% (VC4); 9.76% (VC1) and 8.0% (VC4) at 5, 10 and 15 days, respectively. The other fungi showed only lytic effect without morphological damage to the eggshell. Results demonstrated that P. chlamydosporia was effective in vitro against T. saginata eggs unlike the other fungi.