Integrating the control of helminths in dairy cattle: Deworming, rotational grazing and nutritional pellets with parasiticide fungi.

Thirty-two Friesian cattle under a leaders/followers four-day rotation and passing eggs of trematodes and gastrointestinal nematodes (GIN) were studied in two trials for the integrated control of these helminths over two years. In the first trial, the effect of rotational pasturing was assessed on a group of leaders (milking cows, G-L1) and followers (dried-off cows and heifers, G-F1) supplemented daily with commercial nutritional pellets. In the second trial, leaders (G-L2) and followers (G-F2) were maintained under a rotational pasturing regime; the cows received daily commercial pelleted feed and heifers pellets manufactured with a blend of parasiticide fungi (3 × 105 chlamydospores of both Mucor circinelloides and Duddingtonia flagrans/kg pellet). Deworming via closantel and albendazole was performed in cows in each trial at the beginning of their drying periods, and fourteen days later, the fecal egg-count reductions (FECR) of Calicophoron daubneyi and GIN were from 94 to 100% (average 98 %), while the percentages of reduction of cattle shedding eggs (CPCR) were from 50 to 100% (average 77 % and 82 %, respectively). The heifers were dewormed one time only, at the beginning of each trial, and the values of FECR and CPCR were 100 % against C. daubneyi and 96 % and 83 %, respectively, against GIN. Over a period of 24 months, significantly higher numbers of helminth egg-output were observed in G-L1, with the lowest numbers in G-F2. C. daubneyi egg output was reduced by 5 % (G-L1) and 42 % (G-F1) at the end of trial 1 and by 83 % (G-L2) and 100 % (G-F2) at the end of trial 2; the numbers of GIN egg-output decreased by 13 % (G-L1) and 18 % (G-F1) at the end of trial 1, and by 72 % (G-L2) and 85 % (G-F2) at the end of trial 2. No adverse effects were detected in cattle taking pellets enriched with fungal spores (G-F2). It is concluded that long-term ingestion of spores of M. circinelloides and D. flagrans provides a valuable tool to improve the effect of rotational grazing and to lessen the risk of infection by C. daubneyi and GIN in dairy cattle, and accordingly, the performance of integrated control programs.

Nematicidal activity of silver nanoparticles from the fungus Duddingtonia flagrans.

BACKGROUND: Helminth parasites cause morbidity and mortality in both humans and animals. Most anthelmintic drugs used in the treatment of parasitic nematode infections act on target proteins or regulate the electrical activity of neurons and muscles. In this way, it can lead to paralysis, starvation, immune attack, and expulsion of the worm. However, current anthelmintics have some limitations that include a limited spectrum of activity across species and the threat of drug resistance, which highlights the need for new drugs for human and veterinary medicine. PURPOSE: Present study has been conducted to determine the anthelmintic activity of silver nanoparticles (AgNPs) synthesized from the extract of nematophagous fungus, Duddingtonia flagrans, on the infecting larvae of Ancylostoma caninum (L3). METHODS: The nanoparticles were characterized by visual, ultraviolet, Fourier-transform infrared spectroscopy, transmission electron microscopy (TEM) analysis, and X-ray diffraction. The in vitro study was based on experiments to inhibit the motility of infective larvae (L3), and the ultrastructural analysis of the nematode was performed by images obtained by TEM. RESULTS: The XRD studies revealed the crystalline nature of the nanoparticles, and FTIR results implied that AgNPs were successfully synthesized and capped with compounds present in the extract. The results showed that the green synthesis of AgNPs exhibited nematicidal activity, being the only ones capable of penetrating the cuticle of the larvae, causing changes in the tegmentum, and consequently, the death of the nematode. CONCLUSION: The extract of the fungus D. flagrans is able to synthesize AgNP and these have a nematicidal action.

Toxicity and Antiviral Activity of the Extracts of Submerged Mycelium of Nematophagous Duddingtonia flagrans Fungus in Vero Cell Culture.

We studied toxicity and antiviral activity of aqueous and ethanol extracts of bioactive substances from the biomass of nematophagous fungus Duddingtonia flagrans prepared by submerged culturing of the mycelium. It is found that both extracts were characterized by low toxicity for cultured Vero cells and inhibited reproduction of DNA-viruses in this cell line. Ethanol extract of the fungus exhibited higher in vitro antiviral activity against Herpes simplex virus type 2, ectromelia virus, and vaccinia virus than water extract, which can be due to higher content of proteins, polysaccharides, flavonols, catechins, or carotenes or more effective their combination. The extracts of cultured mycelium of Duddingtonia flagrans fungus containing a complex of bioactive substances can be used for creation of broad-spectrum antiviral drugs against DNA-viruses.