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

Abstract

There are certain saprophytic fungi in the soil able to develop an antagonistic effect against eggs of parasites. Some of these fungal species are ingested by animals during grazing, and survive in their feces after passing through the digestive tract. To identify and isolate ovicidal fungi in the feces of wild captive animals, a total of 60 fecal samples were taken from different wild animals kept captive in the Marcelle Natureza Zoological Park (Lugo, Spain). After the serial culture of the feces onto Petri dishes with different media, their parasicitide activity was assayed against eggs of trematodes (Calicophoron daubneyi) and ascarids (Parascaris equorum). Seven fungal genera were identified in the feces. Isolates from Fusarium, Lecanicillium, Mucor, Trichoderma, and Verticillium showed an ovicidal effect classified as type 3, because of their ability to adhere to the eggshell, penetrate, and damage permanently the inner embryo. Penicillium and Gliocladium developed a type 1 effect (hyphae attach to the eggshell but morphological damage was not provoked). These results provide very interesting and useful information about fungi susceptible for being used in biological control procedures against parasites.

A combined effort to avoid strongyle infection in horses in an oceanic climate region: rotational grazing and parasiticidal fungi

“…Pochonia chlamydosporia and Mucor circinelloides can destroy more than 50% of viable eggs of helminths such as Calicophoron daubneyi , Toxocara canis or Trichuris spp. [ 13 , 18 ]. Duddingtonia flagrans is able to trap and then eliminate 94% of cyathostomin L3 when spores are directly sprayed on the feces of infected horses [ 33 ], and 27–99% when chlamydospores are given orally to horses from a similar climatic place (Curitiba, Brazil) [ 12 ].…”

“…Spores of Mucor circinelloides (ovicidal activity) and D. flagrans (larvicidal activity) were cultured in the submerged medium COPFr (patent Nr PCT/ES2014/070110) for 1.5–2 months at room temperature, until a concentration ≥ 1 × 10 8 spores/l medium was reached [ 17 ]. These fungal species were isolated in the Laboratory of the COPAR Research Group (University of Santiago de Compostela, Spain) [ 18 ].…”

Implementation of Biological Control to the Integrated Control of Strongyle Infection among Wild Captive Equids in a Zoological Park

“…Spores of the ovicide fungus Mucor circinelloides (strain CECT 20824) and the larvicide fungus Duddingtonia flagrans (strain CECT 20823) were jointly obtained in the COPFr submerged culture medium [ 18 – 20 ].…”

Advantageous Fungi against Parasites Transmitted through Soil

“…Based on experiments with plants, traditionally the fungal antagonists of parasites comprise nematode-trapping species (larvicidal), predacious agents, endoparasitic fungi, and egg parasitic fungi (ovicidal) [27]. In the last decades, this classification applies also for defining the activity of soil fungi against parasites affecting mammals ( Table 2).…”

“…Opposite to Duddingtonia flagrans and Monacrosporium thaumasium, the infection by Mucor circinelloides has been associated to clinical cases of mucormycosis, a sporadic and life-threatening infection caused by Mucorales. These are fungi distributed far and wide in the environment, in particular on woody surfaces and soils, where it can be easily isolated [27].…”