Effect Of Inonotus Obliquus Fermentation Products On Growth And Immune Performance In SPF Duck

Inonotus obliquus is a dual-use fungus,and its seeds and fermentation products contain a variety of active substances with antioxidant,immunomodulatory and virus-inhibiting effects.In this study,based on the ability of Inonotus obliquus fermentation product(IOFP)to enhance growth and immune performance in chickens,we investigated whether it has the same promotion effect on SPF(specific pathogen-free)ducks,with the aim of developing new green feed additives and immune enhancers for ducks with growth and immune promotion effects.This study was conducted to provide a basis for the development of new green feed additives and immune enhancers for ducks with growth and immune promoting effects.The main studies were as follows:(1)Effect of IOFP on growth performance and non-specific immune performance of SPF ducks Eighty 1-day-old SPF ducks were randomly divided into experimental and control groups and housed in isolators.In the Experiment group,1.6% IOFP was added to the drinking water,and in the control group,IOFP was not added.The average daily weight gain,daily feed intake,meat ratio and other growth performance indexes of ducks were measured at different time points.The thymus,spleen and bursa of 5 ducks were dissected at 21 d,42d and weighed and immune organ indices were calculated.Lymphocytes were collected from peripheral blood at 14 d,21d and 42 d for the determination of peripheral blood lymphocyte(PBMC)stimulation index,and at 21 d and 42 d for the determination of non-specific immune parameters(total antioxidant capacity(T-AOC),superoxide dismutase(SOD),and nitric oxide(NO).The results showed that Inonotus obliquus fermentation product,IOFP significantly promoted the growth performance and immune organ development of ducks,and effectively enhanced the non-specific immune indexes.(2)Effect of IOFP on the expression of SPF duck set receptors(Toll-like receptors,TLRs)Eighty 1-day-old SPF ducks were randomly divided into experimental and control groups and housed in isolators.The Experiment group added 1.6% IOFP to the drinking water and the control group did not add IOFP.The m RNA expression of different TLRs in peripheral blood of SPF ducks was detected at 21 d,42d using fluorescence quantitative PCR method.The results showed that the changes in the relative expression content of TLRs in ducks fed 1.6% IOFP group were higher than all other groups,with the relative expression of TLR3 being higher at 21 d and 42 d and throughout the experimental period.In conclusion,adding 1.6% fermentation products of Inonotus obliquus to SPF duck drinking water can improve the production performance of the ducks,increase the average weight of theducks,reduce the feed to meat ratio,and improve the intestinal tract morphology to some extent.Through the determination of non-specific immune indexes(T-AOC,SOD,NO),it was proved that the fermentation products of Inonotus obliquus could enhance the antioxidant capacity of the ducks and the intensity of non-specific immune response.Based on the preliminary selection of the relative content changes of TLR1A?TLR1B?TLR2A?TLR3?TLR4?TLR5?TLR7?TLR1 and TLR21,the receptor of IOFP was identified,which establish the foundation for the research of TLR receptor signaling pathway.