Fungi predatory activity on embryonated Toxocara canis eggs inoculated in domestic chickens (Gallus gallus domesticus) and destruction of second stage larvae

Abstract

The objective of this study was to evaluate the infectivity of Toxocara canis eggs after interacting with isolated nematophagous fungi of the species Duddingtonia flagrans (AC001) and Pochonia chlamydosporia (VC4), and test the predatory activity of the isolated AC001 on T. canis second stage larvae after 7 days of interaction. In assay A, 5000 embryonated T. canis eggs previously in contact with the AC001 and VC4 isolated for 10 days were inoculated into domestic chickens (Gallus gallus domesticus), and then these animals were necropsied to collect material (digested liver, intestine, muscles and lungs) at 3-, 7-, 14-, and 21-day intervals after inoculation. In assay A, the results demonstrated that the prior interaction of the eggs with isolated AC001 and VC4 decreases the amount of larvae found in the collected organs. Difference (p < 0.01) was observed in the medium larvae counts recovered from liver, lung, intestine, and muscle of animals in the treated groups when compared to the animals in the control group. At the end of assay A, a percentage reduction of 87.1 % (AC001) and 84.5 % (VC4) respectively was recorded. In the result of assay B, the isolated AC001 showed differences (p < 0.01) compared to the control group, with a reduction of 53.4 % in the recovery of L2. Through these results, it is justified to mention that prior interaction of embryonated T. canis eggs with the tested fungal isolates were efficient in reducing the development and migration of this parasite, in addition to the first report of proven predatory activity on L2.

Isolation of Ovicidal Fungi from Fecal Samples of Captive Animals Maintained in a Zoological Park

“…Prior investigations indicated the antagonistic activity of several fungal species belonging to the genera Fusarium and Trichoderma on eggs of the roundworm Toxocara canis [ 40 , 41 , 42 ]. The ovicidal activity of Pochonia chlamydosporia (formerly Verticillium chlamydosporium ) has been widely reported on eggs of trematodes ( Echinostoma paraensei , Fasciola hepatica ) and ascarids ( T. canis , P. equorum ) [ 19 , 20 , 43 ].…”

“…Most known species with ovicidal activity are Verticillium spp., Pochonia chlamydosporia , Paecilomyces lilacinus , Trichoderma spp., or Mucor circinelloides [ 18 , 19 , 20 ]. By developing the phases of adhesion, colonization, penetration, and deliberation, these fungi develop an ovicidal activity [ 21 , 22 ].…”

Nematicide activity of microfungi (Orbiliales, Orbiliaceae) after transit through gastrointenstinal tract of “Gallus gallus domesticus”

“…Although most predatory activity has been observed in time six hours after administration for all fungal isolates, only the isolated AC001 showed a statistically significant difference (p<0.05) compared to control. Hiura et al (2015) Use of nematophagous fungi as biological controllers of helminth parasites of chickens is an efficient technology, innovative and low cost with possibility of use on all production systems, especially in conventional organic systems.…”

Extracellular biosynthesis of silver nanoparticles using the cell-free filtrate of nematophagous fungus <em>Duddingtonia flagrans</em>

“…In addition, it is harmless to animal and human health and to the environment. 17,18 In the crude extract of D. flagrans, extracellular enzymes can be identified, such as proteases and chitinases, capable of hydrolyzing the nematode cuticle, which facilitate predation of the parasite. Therefore, its applicability has been studied extensively.…”