Antagonistic activity of the fungusPochonia chlamydosporiaon mature and immatureToxocara caniseggs

Abstract

<jats:title>SUMMARY</jats:title><jats:p><jats:italic>In vitro</jats:italic>tests were performed to evaluate the ability of 6 isolates of the nematophagous fungus<jats:italic>Pochonia chlamydosporia</jats:italic>to infect immature and mature<jats:italic>Toxocara canis</jats:italic>eggs on cellulose dialysis membrane. There was a direct relationship between the number of eggs colonized and the increase in the days of interaction, as well as between the number of eggs colonized and the increase in the concentration of chlamydospores (<jats:italic>P</jats:italic>&lt;0·05). Immature eggs were more susceptible to infection than mature eggs. The isolate Pc-04 was the most efficient egg parasite until the 7th day, and showed no difference in capacity to infect mature and immature eggs in comparison to Pc-07 at 14 and 21 days of interaction, respectively. Isolate Pc-04 was the most infective on the two evolutionary phases of the eggs at most concentrations, but its ability to infect immature eggs did not differ from that presented by the isolates Pc-07 and Pc-10 at the inoculum level of 5000 chlamydospores. Colonization of infective larvae inside or outside the egg was observed in treatments with the isolates Pc-03, Pc-04, Pc-07 and Pc-10. The isolate Pc-04 of<jats:italic>P. chlamydosporia</jats:italic>has great biological capacity to destroy immature and mature<jats:italic>T. canis</jats:italic>eggs in laboratory conditions.</jats:p>

A method to evaluate relative ovicidal effects of soil microfungi on thick-shelled eggs of animal-parasitic nematodes

“…This strain is likely to be less effective under field conditions. Similarly, P. chlamydosporia Biotype 10 had a large negative effect on the viability of T. canis eggs which corresponds to findings by Maciel et al (2012) with other isolates of the fungus. P. lilacinum Strain 251 only had a minor effect comparable to results for other isolates as reported by Araújo et al (1995) and Carvalho et al (2010).…”

Saprophytic Filamentous Fungi against Helminths Affecting Captive Wild Animals

“…-Nematode-trapping fungi: These are characterized by producing an extensive system of hyphae or mycelium where, at certain intervals of development, they present specialized structures such as hyphal nets, knobs, branches, or rings to trap and sustain live nematodes (larval stages); therefore, they are ideal for the control of parasites such as strongyles [31]. Examples of this group are Duddingtonia flagrans, Arthrobotrys spp., and Monacrosporium thaumasium [32][33][34][35], which can develop different types of traps in which the mobile parasitic stages become caught, absorbed, and finally destroyed. -Predatory fungi or egg parasites: The hyphae of these fungi adhere to and penetrate the egg through small pores in the vitelline layer, causing permeability alterations.…”

“…On the other hand, strongyles have a mobile infective phase and can be controlled by means of nematode-trapping fungi (Figure 1). spp., and Monacrosporium thaumasium [32][33][34][35], which can develop different types traps in which the mobile parasitic stages become caught, absorbed, and finally d stroyed.…”