Veterinária
URI permanente desta comunidadehttps://locus.ufv.br/handle/123456789/11842
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Resultados da Pesquisa
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 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 Interaction between the nematophagous fungus Duddingtonia flagrans and infective larvae of Haemonchus contortus (Nematoda: Trichostrongyloidea)(Journal of Helminthology, 2008-12) Araújo, J. V.; Campos, A. K.; Guimarães, M. P.The interaction between Duddingtonia flagrans and infective larvae of Haemonchus contortus was studied in vitro under optical and scanning electron microscopy. Trap formation by the fungus started 9 hours after inoculation and first larvae were found 11 hours after larval inoculation on colonies grown on the surface of dialysis membranes. Scanning electron micrographs were taken 12, 24, 36 and 48 h after larval predation. Details of predation structures and fungus-larvae interaction are described. A mucilaginous substance occurred at the points of adherence of traps to nematode cuticle. Bacteria were also found at some points of interaction between fungus and larval cuticle. Cuticle penetration by fungus hyphae occurred only 48 h after predation.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 In vitro activity of a serine protease from Monacrosporium thaumasium fungus against first-stage larvae of Angiostrongylus vasorum(Parasitology Research, 2012-01-10) Braga, Fabio R.; Araújo, Jackson V.; Soares, Filippe E. F.; Lima, Walter dos Santos; Mozer, Lanuze R.; Queiróz, José H.A serine protease from the nematophagous fungus Monacrosporium thaumasium (NF34a) was purified, partially characterized and tested in vitro in control of the first larval stage of Angiostrongylus vasorum. NF34a grew in liquid culture medium, producing its crude extract that was purified by ion exchange chromatography. The fractions with high protease activity were collected in a pool, and elution of proteases was monitored by enzymatic assay and protein content. Purification steps were monitored by sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE). Protease activity was determined under different pH and temperature conditions, and the inhibitor effects of metal ions and phenylmethylsulfonyl fluoride (PMSF) were assessed. In an experimental test, the infection process of NF34a on first-stage larvae of A. vasorum was investigated. A purified serine protease (Mt1) was identified, with an approximate molecular mass of 40 kDa and apparent homogeneity in SDS-PAGE, having optimal activity at pH 7.0 to 8.0 and temperature of 60°C. Mg2+ and Zn2+ partially inhibited the activity of Mt1 while PMSF inhibited it completely. Mt1 production was observed when NF34a was grown using first-stage larvae of A. vasorum as the only source of carbon and nitrogen. These results show that the enzyme may have a possible role in the infection process of the larvae. In the in vitro test of applicability against A. vasorum L1, we observed a reduction in the number of larvae of 23.9% (p < 0.05) in the group treated with Mt1 compared with the control group. However, even this low reduction demonstrates that the Mt1 is important in the infection process.Item Destruction of Anoplocephala perfoliata eggs by the nematophagous fungus Pochonia chlamydosporia(Journal of Equine Veterinary Science, 2010-12) Silva, André R.; Araújo, Jackson V.; Braga, Fábio R.; Alves, Camila D. F.; Ribeiro Filho, José DantasThe in vitro effect of an isolate of the nematophagous fungus Pochonia chlamydosporia (VC1) on the eggs of Anoplocephala perfoliata was evaluated. The eggs were morphologically analyzed for their integrity using light microscopy (10× objectives), plated on 9.0-cm diameter petri dishes containing 2% WA culture medium with and without fungal isolate (control), grown for 10 days, and 10 replicates were prepared per group. In all, 1000 eggs of A perfoliata were plated on petri dishes containing 2% water agar culture medium with (VC1) and without the fungal isolate (control). After 3, 5, 7, and 10 days, approximately 100 eggs were removed from each plate and classified on the basis of the following parameters: without alteration; type 1, lytic effect without morphological damage to eggshell; type 2, lytic effect with morphological alteration of embryo and eggshell; and type 3, lytic effect with morphological alteration of embryo and eggshell, in addition to hyphal penetration and internal egg colonization and destruction. The P chlamydosporia fungus demonstrated ovicidal activity (P < .05) on the eggs of A perfoliata in the studied intervals presenting type 3 effects of 35%, 42.5%, 53.83%, and 71.17% for the intervals 3, 5, 7, and 10 days, respectively. P chlamydosporia is a potential biological control agent for the eggs of A perfoliata.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 Biological control of sheep gastrointestinal nematodiasis in a tropical region of the southeast of Brazil with the nematode predatory fungi Duddingtonia flagrans and Monacrosporium thaumasium(Parasitology Research, 2009-09-16) Silva, Andre R.; Araújo, Jackson V.; Braga, Fabio R.; Frassy, Luiza N.; Tavela, Alexandre O.; Carvalho, Rogerio O.; Castejon, Fernanda V.Formulations in matrix of sodium alginate (pellets) of the nematode predatory fungi Duddingtonia flagrans and Monacrosporium thaumasium were evaluated in the biolog- ical control of sheep gastrointestinal nematodiasis. Three groups (1, 2, and 3), each one with eight sheep of the Santa Inês breed, at the ages of 15–48 months, were placed in paddocks of Brachiaria decumbens for 5 months. In group 1, each animal received 1 g/10 kg of live weight (l.w.) of pellets of D. flagrans (0.2 g of fungus/10 kg l.w.). In group 2, each animal received 1 g/10 kg of l.w. of pellets of the fungus M. thaumasium (0.2 g of fungus/10 kg l.w.), twice a week, for 5 months. In group 3 (control), the animals received 1 g/10 kg of live weight of pellets without fungus. The monthly averages of the egg countings per gram of feces of the animals of groups 1 and 2 treated were 71.6% and 61.1% smaller, respectively, in comparison to the animals of group 3 (control). The treatment of sheep with pellets containing the nematophagous fungi D. flagrans and M. thaumasium may be used as an alternative for the control of sheep gastrointestinal nematodiasis.
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