Avaliação de fungos nematófagos sobre larvas infectantes de Strongyloides westeri e ovos de Toxocara canis

• Ano de defesa: 2012
• Autor(a) principal: Araujo, Juliana Milani
• Orientador(a): Araújo, Jackson Victor de
• Banca de defesa: Lima, Eraldo Rodrigues de , Braga, Fábio Ribeiro , Negrão-correa, Deborah Aparecida , Lima, Walter dos Santos
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: por
• Instituição de defesa: Universidade Federal de Viçosa
• Programa de Pós-Graduação: Doutorado em Medicina Veterinária
• Departamento: Biotecnologia, diagnóstico e controle de doenças; Epidemiologia e controle de qualidade de prod. de
• País: BR
• Palavras-chave em Português: Fungos nematófagos; Toxocara canis; Cães
• Palavras-chave em Inglês: Nematophagous fungi; Toxocara canis; Dogs
• Área do conhecimento CNPq: CNPQ::CIENCIAS AGRARIAS::MEDICINA VETERINARIA
• Link de acesso: http://locus.ufv.br/handle/123456789/1454

The objective of this work was to evaluate the action of three isolates of predatory fungi Duddingtonia flagrans (AC001), Monacrosporium thaumasium (NF34) and Arthrobotrys robusta (I-31) in in vitro assay regarding their capacity to prey infective larvae (L3) of Strongyloides westeri and, to evaluate in vitro three concentrations of chlamydospores (1,000, 10,000 and 100,000) of the nematophagous fungus Pochonia chlamydosporia (isolates VC1 and VC4) in the destruction of Toxocara canis eggs. In relation to the fungi predators when compared to the control group, one can observe that there was a significant reduction (P<0.01) of 80.4%, 67.9%, 72.8%, in the means of recovered infective larvae of S. westeri from treatments with the isolates AC001, NF34 and I-31, respectively. All tested isolates were efficient at capturing S. westeri (P>0.01) when tested in vitro. In the test of ovicidal evaluation with the fungus P. chlamydosporia on eggs of T. canis, each Petri dish contained thousand eggs of T. canis with only one concentration of chlamydospores of VC1 or VC4 in water-agar 2% (WA 2%), and only one thousand eggs in WA 2% in the control groups. Within 15 days, one hundred eggs were removed from each Petri dish and the ovicidal effect was evaluated according to morphological alterations. The higher percentage to effect of the type 3 was observed in concentration of 100,000 chlamydospores to both isolates. After in vitro evaluation, predatory and ovicidal fungi were evaluated in vivo regarding their capacity to withstand the passage through the gastrointestinal tract of horses (Duddingtonia flagrans and Monacrosporium thaumasium) on S. westeri and dogs (Pochonia chlamydosporia) on T. canis eggs. The predatory fungi survived the passage through the gastrointestinal tract of horses and were efficient in preying upon the L3 since the first collection (12h) (P <0.01) compared to control (without fungi). The ovicidal fungus also survived the passage through the gastrointestinal tract of dogs keeping its ovicidal activity on T. canis eggs. These results demonstrated that the fungi D. flagrans and M. thaumasium were promising to be used for biological control of S. westeri as well as from the results obtained suggest that the fungus P chlamydosporia (VC4) could be used as a tool for biological control of T. canis eggs.