Soy protein polymers as controlled release system of fungi nematophagous to the control nematode parasites in ruminants

SAGÜÉS, MARÍA FEDERICA; FUSÉ, LUIS; FERNÁNDEZ, ALICIA SILVINA; PURSLOW, PETER; IGLESIAS, LUCÍA; SAUMELL, CARLOS

Encuentro; VI Encuentro Anual de Biólogos en Red; 2011

Due to the rapid increase in cases of anthelmintic resistance as well as the increasing demand of safe food for human consumption obtained using environmentally-friendly technologies, it is imperative to find alternatives for the control of gastrointestinal parasites of ruminants. Among these, Biological Control (BC) is based on natural organisms such as Duddingtonia flagrans, a nematophagous fungus which has the ability to go through the gastrointestinal tract of livestock and maintaining intact its germination and predatory activity in the environment, thus reducing the number of infective larvae in faecal pats. Current research focuses on the obtention of formulations used as vehicles for the spores of nematophagous fungi. Soy proteins polymers (SPP) have a great potential as a controlled release system (CRS) for active compounds, such as nutrients, medicine and could be used therapeutically. SPP forms a stable polymer, very resistant to degradation because its ability to polymerise into different polymeric structures such as sheets or plastics. The purpose of this trial was to evaluate the predatory activity of D. flagrans included in a SPP formulation such as CRS; determine the fungi release from polymers and the suitable physic structure for bucoesophagic probe administration in sheep, and to observe the time of permanency of the SPP in the rumen of a cannulated sheep. Ten replicates were made. The SPP was extracted weekly for the observation of the physical structure and faeces were collected to observe the predatory activity of teh fungus in Petri dishes with water agar 2% and Panegrellus spp as baits. The result showed that polymer formulation did not affect the predatory activity of D. flagrans and the fungal release was successful. The SPP remained in the rumen degrading slowly for 4 weeks and liberated D. flagrans constantly in faeces. Therefore, the use of SPP as vehicle of nematophagous fungi for nematode control in ruminants could be the base for a potential biodegradable controlled-release system.