Studies On Screening Of Different Batch Media And Modes Of Clinic Application Of Nematode-trapping Fungus-Duddingtonia Flagrans

Nematode-trapping fungus-Duddingtonia flagrans is thought of as the most practical application potential for the biological control of animal gastrointestinal nematodes. In order to explore the best way of batch cultivation and the application mode for veterinary clinical practice in China, the research were done through optimization of D.flagrans in different culture conditions, screening the better cultivation time and the suitable batch culture media for mass production. Meanwhile, the freeze-dried formulations of nematode-trapping fungus-D.flagrans were made and were used in clinical tests with different nematocide pattern to provide the basic references for clinical scale application of nematode-trapping fungus-Duddingtonia flagrans.The results show that:the spore germination rate and growth rate were higher when the lyophilized chlamydospores of D.flagrans, which were cultivated to the 3rd week or 4th week before lyophilized, were tested, although there was no statistic significant differences between with the corn medium and with the barley one (P> 0.05), but the former was better. The lyophilized biological preparations had no obvious change to save more than half year at 4 ℃ refrigerator.While nematode-trapping fuhgus-D.flagrans freeze-dried preparation combined with ivermectin in sheep parasitied with nematode were applied, the larvae reduced rate could be up to 98.5%; in contrast, the larvae of combined with albendazole reduced rate could reach 100%. Alone with the fungus or the chemical it was significant difference with the combination (P< 0.05). Indicating the combination application of lyophilized biological preparation of nematode-trapping fungus-D.flagrans used with anthelmintic would achieve better clinical efficacy. It deserve further in-depth study in veterinary practice.