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URI permanente para esta coleçãohttps://locus.ufv.br/handle/123456789/11852
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Item Efficacy of Monacrosporium thaumasium in the control of goat gastrointestinal helminthiasis in a semi-arid region of Brazil(Parasitology Research, 2013-02) Braga, Fabio Ribeiro; Araújo, Jackson Victor de; Vilela, Vinícius Longo Ribeiro; Feitosa, Thais Ferreira; Lucena, Samuel Cavalcante de; Dantas, Elaine Silva; Athayde, Ana Célia Rodrigues; Silva, Wilson WouflanThe aim of the present study was to test a pellet formulation of Monacrosporium thaumasium in a sodium alginate matrix in the biological control of goat gastrointestinal helminthiasis in a semi-arid region of northeastern Brazil. An area of 2.4 ha was divided into three paddocks, with seven goats kept on each paddock, during the months of March to August 2011: group 1 received 3 g/10 kg live weight of M. thaumasium pellets (NF34a) twice a week; group 2 was given 0.2 mg/kg of 0.2 % moxidectin orally every 30 days; and group 3 received 3 g/10 kg live weight of pellets without fungus twice per week. Each month, two tracer goats was placed in each group for 30 days and then killed and necropsied. The M. thaumasium group showed a 34 % reduction in eggs per gram, higher packed cell volume rates and a lower parasitic load in the tracers compared with the other groups. The 0.2 % moxidectin group had weight gain of 5.7 kg; the M. thaumasium group, 3.6 kg; and the control group had an average reduction in weight of 1.1 kg. The use of M. thaumasium pellets may be effective as an alternative method to control goat gastrointestinal helminthiasis in the semi-arid region of northeastern Brazil.Item Viability and nematophagous activity of the freeze-dried fungus Arthrobotrys robusta against Ancylostoma spp. infective larvae in dogs(Veterinary Parasitology, 2010-10-20) Carvalho, Rogério Oliva; Braga, Fabio Ribeiro; Araújo, Jackson VictorViability and in vitro and in vivo activities of freeze-dried conidia of the predatory fungus Arthrobotrys robusta (I-31) were evaluated against infective larvae (L3) of Ancylostoma spp. in dogs. A. robusta conidia were lyophilized and stored at 4 °C for a month. Freeze-dried conidia were diluted to 1 × 103 conidia/ml and tested in vivo. The treated group consisted of a solution containing conidia (1 ml) and 1000 Ancylostoma spp. (L3) placed on Petri dishes plated with 2% water–agar (2% WA), at 25 °C, in the dark for 10 days. The control group consisted of 1000 Ancylostoma spp. L3, plated on 2% WA. After 10 days, Ancylostoma spp. L3 from both the treated and the control groups were recovered and counted. The in vivo test was performed on two dogs by administering a single oral dose of freeze-dried conidia (1.5 × 105) in aqueous solution to one animal and only water to the other. Fecal samples were collected at 12, 24 and 48 h after the treatments, plated 2% WA plates and incubated at 25 °C for 15 days. A thousand Ancylostoma spp. L3 larvae were spread on these plates. At day 15, infective L3 recovered from the treated and control groups were counted. In the in vitro test, A. robusta was able to survive the freeze-drying process, grow in the plates, form traps and capture Ancylostoma spp. L3. There was a 75.38% decrease in the number of infective larvae recovered from the treated group. The in vivo test showed that freeze-dried A. robusta conidia survived the passage through the gastrointestinal tract of the treated dog, was able to grow in the plates and capture Ancylostoma spp. L3, reducing the number of recovered L3 (p < 0.01). Freeze-drying can be an alternative method for conservation of conidia of nematophagous fungi.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 Biological control of horse cyathostomin (Nematoda: Cyathostominae) using the nematophagous fungus Duddingtonia flagrans in tropical southeastern Brazil(Veterinary Parasitology, 2009-05-05) Braga, Fabio Ribeiro; Araújo, Jackson Victor; Silva, André Ricardo; Araujo, Juliana Milani; Carvalho, Rogério Oliva; Tavela, Alexandre Oliveira; Campos, Artur Kanadani; Carvalho, Giovanni RibeiroThe viability of a fungal formulation using the nematode-trapping fungus Duddingtonia flagrans was assessed for the biological control of horse cyathostomin. Two groups (fungus-treated and control without fungus treatment), consisting of eight crossbred mares (3–18 years of age) were fed on Cynodon sp. pasture naturally infected with equine cyathostome larvae. Each animal of the treated group received oral doses of sodium alginate mycelial pellets (1 g/(10 kg live weight week)), during 6 months. Significant reduction (p < 0.01) in the number of eggs per gram of feces and coprocultures was found for animals of the fungus-treated group compared with the control group. There was difference (p < 0.01) of 78.5% reduction in herbage samples collected up to (0–20 cm) between the fungus-treated group and the control group, during the experimental period (May–October). Difference of 82.5% (p < 0.01) was found between the fungus-treated group and the control group in the sampling distance (20–40 cm) from fecal pats. During the last 3 months of the experimental period (August, September and October), fungus-treated mares had significant weight gain (p < 0.01) compared with the control group, an increment of 38 kg. The treatment with sodium alginate pellets containing the nematode-trapping fungus D. flagrans reduced cyathostomin in tropical southeastern Brazil and could be an effective tool for biological control of this parasitic nematode in horses.