Field evaluation of Duddingtonia flagrans IAH 1297 for the reduction of worm burden in grazing animals: Pasture larval studies in horses, cattle and goats

Abstract

A series of placebo-controlled trials were conducted in horses, cattle and goats in different seasons and bioclimatic regions of New South Wales and Queensland, Australia, to evaluate the ability of BioWorma®, a feed supplement containing the spores of Duddingtonia flagrans IAH 1297, to reduce the larval development of parasitic gastrointestinal nematodes (GIN) and their subsequent migration from faeces onto the surrounding pasture. In each trial, faeces were collected from animals harbouring a burden of nematode parasites following a period of supplementation with a placebo and again after supplementation with BioWorma. The faeces were manually placed onto pasture plots at one or two distinct geographical sites and the effect of treatment was determined by subsequent monitoring the numbers of parasitic larvae on the pasture surrounding the faecal pats at two weekly intervals over an eight week period. The results for these studies showed that administration of BioWorma at a minimum daily dose of 3 × 10 spores/kg bodyweight reduced parasite larvae in the pasture surrounding the faeces by 53-99 % over an eight week post treatment period in horses, cattle and goats in a range of bioclimatic zones and in different seasons. Overall, the studies with BioWorma show substantial reductions in GIN infectivity of pasture surrounding faeces of treated horses, cattle and goats (P < 0.05). Results indicate that the use of BioWorma in these host species would lead to decreased levels of GIN infection in animals grazing pasture when this product is used and would provide an alternative means of controlling parasitic nematodes.

Systematic review of gastrointestinal nematodes of horses from Australia

“…Once passed, the fungus germinates, and fungal hyphae form a network (mesh) of sticky traps throughout the faecal mass which inhibits the development of free-living larval stages reducing the incidence of infection in grazing animals. The effectiveness of chlamydospores (3 × 10 4 spores/kg) of D. flagrans strain IAH 1297 has recently been trialed in horses from New South Wales [85]. This resulted in a 53–94% reduction in parasite larvae (principally cyathostomins, Strongylus spp.…”

“…This resulted in a 53–94% reduction in parasite larvae (principally cyathostomins, Strongylus spp. and T. axei ) on the pasture over the eight weeks of the study across several different climatic conditions [85]. Given that this type of approach could be a valuable alternative in GIN control, further studies are urged to evaluate the effect of nematophagous fungi on equine GINs in additional agroclimatic regions of Australia.…”

Gastrointestinal nematodes of goats: host–parasite relationship differences in breeds at summer mountain pasture in northern Italy

“…Regular deworming effectively controls internal parasites in grazing dairy goats, but it should be properly carried out to prevent or slow down the onset of anthelmintic resistance, which has already been reported in northern Italy and neighbouring regions (30,35,36,38). In this regard, in recent years strategic or targeted selective treatments have been suggested and other strategies have been developed to improve the management of gastrointestinal parasites in goats, such as nutritional supplementation with minerals, vitamins, condensed tannins, spores of Duddingtonia flagrans, and copper oxide wire particles (13,20,25,29). Also, selection of animals with greater resistance or resilience to GIN enhances productivity under conditions of risk of infection by parasites and, as this leads to less frequent treatments, reduces selection pressure for anthelmintic resistance (26).…”

Sustainable Control of Equine Nematodes: A Literature Review about Control by Fungal Cultures

“…In everyday reasoning it is possible to think that when several researchers draw similar conclusions by several studies the generalizability is achieved. In addition, the controlling effect of nematodes-destroying fungi has been demonstrated in other species, among pig, cow and small ruminants (Larsen, 1999;Healey et al, 2018). However, excluding the study of Healey et al, the effect has been demonstrated by same active researchers by same methods in same climate conditions.…”

“…It is still unclear, based on these research reports, what is a convenient dose and feeding period. Daily treatments are previously and more recently recommended (Fernandez et al, 1997(Fernandez et al, , 1999Healey et al, 2018), but the dose administered to the animals may be adjusted according to the isolate employed (Buzatti et al, 2015). On the other hand, a single dose (Tavela et al, 2013), twice a week administration (Herná ndez et al, 2018) and longer intervals (Buzatti et al, 2015) can also be effective alternatives to the daily treatment.…”