ENZYMATIC ACTIVITY OF THE FUNGUS Pochonia chlamydosporia (SORDARIOMYCETES: HYPOCREALES) AND ITS OVICIDAL POTENTIAL ON EGGS OF Toxocara canis (NEMATODA: ASCARIDIDA)

Resumo

 Biological control is considered one of the most used alternative measures to combat helminths of relevance in veterinary medicine and public health. Among these parasites, Toxocara canis stands out for its high prevalence and worldwide distribution, in addition to being the main cause of visceral larva migrans in man. The present work aimed the fungus Pochonia chlamydosporia (isolate Pc-10) on eggs of T. canis. In order to do this, fertile nematode eggs were obtained by dissection of adult females fertilized specimens. After obtaining the eggs, they were inserted into 24 well plates previously À lled with different concentrations of enzymatic extract of the fungus (100, 200, 400 and 500 μL). In addition, the behavior of P. chlamydosporia hyphae on Toxocara canis eggs was also observed in 2% wateragar medium (2% WA+ fungal isolate) when compared to the control group (2% WA + water). It was veriÀ ed ovicidal activity with the enzymatic extract of P. chlamydosporia at concentrations of 400 and 500 μL. At the same time, after 12 days of exposure of the T. canis eggs to P. chlamydosporia mycelia it was possible to observe the fungus action on eggshells, including penetration of the hyphae and colonization of the egg inside. The results conÀ rm the ovicidal potential of the fungus and suggest its applicability in toxocariasis control programs.

 Keywords: Pochonia chlamydosporia, Toxocara canis, Toxocariasis, Nematodes, Biological control.