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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11852
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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 Ascaris suum eggs by Pochonia chlamydosporia fungus(Veterinary Research Communications, 2011-07-28) Ferreira, Sebastião Rodrigo; Araújo, Jackson Victor de; Braga, Fábio Ribeiro; Araujo, Juliana Milani; Frassy, Luiza Neme; Ferreira, Aloízio SoaresAscaris suum is a gastrointestinal nematode parasite of swines. The aim of this study was to observe Pochonia chlamydosporia fungus on biological control of A. suum eggs after fungus passage through swines gastrointestinal tract. Eighteen pigs, previously dewormed, were randomly divided into three groups: group 1, treated with the fungus isolate VC4; group 2, treated with the fungus isolate VC1 and group 3 did not receive fungus (control). In the treated groups, each animal received a 9 g single dose of mycelium mass containing P. chlamydosporia (VC1 or VC4). Thereafter, animal fecal samples were collected at the following intervals: 8, 12, 24, 36, 48, 72 and 96 h after treatment beginning and these were poured in Petri dishes containing 2% water-agar culture medium. Then, 1,000 A. suum eggs were poured into each dish and kept in an incubator at 26°C and in the dark for 30 days. After this period, approximately 100 eggs were removed from each Petri dish and morphologically analyzed under light microscopy following the ovicidal activity parameters. The higher percentage observed for isolated VC4 eggs destruction was 57.5% (36 h) after fungus administration and for isolate VC1 this percentage was 45.8% (24 h and 72 h) (p > 0.01). P. chlamydosporia remained viable after passing through the gastrointestinal tract of swines, maintaining its ability of destroying A. suum eggs.Item Ovicidal action of a crude enzymatic extract of the fungus Pochonia chlamydosporia against cyathostomin eggs(Veterinary Parasitology, 2010-05-11) Braga, Fabio Ribeiro; Araújo, Jackson Victor; Carvalho, Rogério Oliva; Silva, André Ricardo; Araujo, Juliana Milani; Soares, Filippe E. Feitas; Geniêr, Hugo L. André; Ferreira, Sebastião Rodrigo; Queiroz, José HumbertoThe aims of this study were to test the action of the fungal extract of Pochonia chlamydosporia (VC4) on the hatching of cyathostomin eggs plated in Petri dishes containing 2% water-agar (2% WA) and its enzymatic activity in fecal cultures, in two experimental assays (A and B). The fungus P. chlamydosporia (VC4) was cultured in Erlenmeyer flasks (250 ml) containing 50 ml of liquid minimal medium supplemented with 0.2% gelatin for production of the crude enzymatic extract. Approximately 1 kg of fresh feces was collected directly from the rectum of crossbred horses naturally infected with cyathostomins. The fecal material was used to obtain eggs and prepare fecal cultures. For assay A, one thousand eggs were plated on 4.5 cm diameter Petri dishes together with 5 ml of VC4 fungal filtrate and incubated at 26 °C in the dark for 24 h. The control group consisted of 1000 eggs in Petri dishes containing 10 ml of distilled water, which were incubated under the same conditions. After 24 h, the total number of cyathostomin larvae present in each plate of the treated and control groups was counted. For assay B, about 20 g of feces were added with 10 ml of fungal extract of P. chlamydosporia (VC4) and incubated at 26 °C for 8 days. Third stage larvae (L3) were recovered at the end of this period. Significant difference (p < 0.01) was found for the number of larvae between the treated group and the control at end of assay A. A 72.8% reduction in the hatching of cyathostomin eggs was found in the plates of the treated group compared with the control group. At the end of 8 days, the fungal extract of P. chlamydosporia (VC4), in assay B, was effective in reducing the number of L3 cyathostomins in the treated group by 67.0% compared with the control group. Significant difference (p < 0.01) was found between the means of L3 recovered from the treated group and the control group. The results of this work showed that crude enzymatic extract of P. chlamydosporia (VC4) was effective in reducing hatching of cyathostomin eggs and therefore could be used as a biological control agent of this nematode.Item Viability of the nematophagous fungus Pochonia chlamydosporia after passage through the gastrointestinal tract of horses(Veterinary Parasitology, 2009-11-24) Braga, Fabio Ribeiro; Araújo, Jackson Victor; Silva, André Ricardo; Carvalho, Rogério Oliva; Araujo, Juliana Milani; Ferreira, Sebastião Rodrigo; Carvalho, Giovanni RibeiroThe predatory capacity of the nematophagous fungus Pochonia chlamydosporia (isolate VC4) embedded in sodium alginate pellets after passage through the gastrointestinal tract of horses was assessed in vitro against Oxyuris equi eggs. Twelve previously dewormed crossbred mares, average weight of 362.5 kg (±21) were used in the experiment. Each animal of the treated group received an oral dose (100 g) of sodium alginate pellets containing P. chlamydosporia mycelial mass. The control group received pellets without fungus. Faecal samples from fungus-treated and control groups were collected at intervals of 8, 12, 24, 36, 48 and 72 h after pellet administration and placed in Petri dishes containing 2% water-agar. One thousand eggs of O. equi were plated in Petri dishes of both treated and control groups, with six replicates, and incubated in oven, 25 °C, in the dark, for 30 days. At the end of the experiment, one hundred eggs were removed from each Petri dish and classified according to the following parameters: type 1, physiological and biochemical effect without morphological damage to eggshell, with hyphae adhered to the shell; type 2, lytic effect with morphological change in the eggshell and embryo without hyphal penetration, and type 3, lytic effect with morphological change in the eggshell and embryo, with hyphal penetration and internal egg colonization. Chlamydospore production was observed in Petri dishes of the treated group. The isolate VC4 remained viable after passing through the gastrointestinal tract of horses and maintained the ovicidal activity against O. equi eggs when compared with the control group (p < 0.01) after each collection interval: 29.1% (8 h), 28.2% (12 h), 31.1% (24 h), 27.4% (36 h), 30.9% (48 h) and 28.4% (72 h). The results suggest that P. chlamydosporia could be used as an effective biological control agent of O. equi eggs in natural conditions.Item Effect of the fungus Pochonia chlamydosporia on Echinostoma paraensei (Trematoda: Echinostomatidae)(Acta Tropica, 2014-07-10) Lelis, Rosane Teixeira; Braga, Fabio Ribeiro; Carvalho, Lorendane Millena de; Paula, Alessandra Teixeira de; Araujo, Juliana Milani; Fausto, Mariana Costa; Rodrigues, João Victor Facchini; Soares, Filippe Eliasde Freitas; Araújo, Jackson Victor de; Maldonado Junior, Arnaldo; Garcia, Juberlan SilvaEchinostoma paraensei is a trematode of the genus Echinostoma that causes echinostomiasis in humans. The objectives of this study were to: evaluate the ovicidal activity of the nematophagous fungus Pochonia chlamydosporia (VC1 and VC4) on a solid medium 2% water–agar (2% WA) against E. paraensei eggs (assay A); evaluate ovicidal effect (destruction of eggs) of the isolate VC4 in supplemented culture media (assay B); and evaluate the ovicidal ability of the crude extract (VC4) on E. paraensei eggs (assay C). Eggs of E. paraensei (assay A) were placed in Petri dishes containing 2% WA with an isolate of the fungus P. chlamydosporia (VC1 and VC4) grown for 10 days, and without fungus as a control and evaluated regarding their destruction. In assay B, eggs of E. paraensei were placed in Petri dishes with different supplemented culture media and with VC4 isolate and the destruction of eggs was examined at the end of 25 days of interaction. In assay C, effects of the crude extract of P. chlamydosporia (VC4) on eggs were evaluated at the end of 7 days. In assay A, there was no difference (p > 0.05) in ovicidal activity among the tested isolates (VC1 and VC4); however, the highest percentage for ovicidal activity (type 3 effect) was demonstrated by the isolate VC4. In assay B, the culture medium starch–agar showed the best results for the destruction of the eggs, with a percentage of 46.6% at the end of the assay. In assay C, the crude extract of VC4 was effective in the destruction of E. paraensei eggs, with a percentage reduction of 53%. The results of this study demonstrate that a rich culture medium with a greater availability of carbon and nitrogen may interfere directly in the predatory characteristics of ovicidal fungi.Item Ação ovicida do extrato bruto enzimático do fungo Pochonia chlamydosporia sobre ovos de Ancylostoma sp(Revista da Sociedade Brasileira de Medicina Tropical, 2010-09-01) Braga, Fabio Ribeiro; Araujo, Juliana Milani; Silva, André Ricardo e; Araújo, Jackson Victor de; Carvalho, Rogério Oliva; Soares, Filippe Elias de Freitas; Queiroz, José Humberto de; Gênier, Hugo Leonardo AndréAncylostoma sp é um geo-helminto potencialmente zoonótico. O objetivo deste trabalho foi avaliar in vitro a ação do extrato bruto enzimático de Pochonia chlamydosporia (VC4) sobre ovos de Ancylostoma sp, em meio ágar-água 2% e em cultura de fezes. Observou-se um percentual de redução na eclosão dos ovos de Ancylostoma sp, de 76,8% na placas de Petri do grupo tratado em relação ao grupo controle. O extrato bruto enzimático de Pochonia chlamydosporia foi eficiente na redução da eclosão dos ovos de Ancylostoma sp, podendo ser utilizado como controlador biológico desse nematoide.