The Development Of New Chinese Herbal Medicament For IBD

In view of the present control situation of Infectious Bursal Disease(IBD), A new drug was developed with Chinese herbal medicine in this research. The details are as follows:.1.Screening of monarch drug: The eight herbal medicines, astragalus root (AR), forsythia fruit(FF), isatis root(IR), isatis leaf(IL), honeysuckle flower(HF), lithosperm root(LR), epimedium(Ep) and dandelion herb(DH)were selected to make into crude extracts. After their safe concentration on chick embryo fibroblast(CEF) were determined, their effects on cell-infecting of infectious Bursal disease virus(IBDV) were observed by means of cell culture. The results showed that only AR could inhibit the virus. Therefore it was chosen as monarch drug in prescription.2.Clinical experiment: According to the component principle of Chinese herhal medicine, three prescriptions were established and made into oral liquid. Their clinical curative effects were compared by four experiments with 1043 chickens. The results indicated that the best curative effect, lightest pathologic bleeding and most marked weight-gaining occurred in group recipe 3. consequently recipe 3 could be used as the first prescription for IBD.3. Verification in vitro: The effects of the two recipes on cell-infecting of IBDV were compared by cell culture again. The results were consistent with that of clinical experiment.4.Dosage experiment: Clinical experiments were conducted again with 372 chickens and recipe 3 at three doses of high (1.5g), middle (Ig) and lower (0.5g). Meanwhile the administration time and course of treatment were compared. The results displayed that the best curative effect presented at middle dose and 4 days course beginning 6h after inoculation of IBDV. These could be used as the best dose and course of recipe 3.5.Prevention and immunopotentiation experiment: The Clinical experiments were conducted again with recipe 3 alone or together with IBDV vaccine. The mortality, pathologic bleeding, weight-gaining of survival subject chickens, Bursal index, spleen index and IBDV antibody titer were compared. The results showed that the recipe 3 couldreduce the death rate and increase titer of specific antibody in experimental chicken when the drug was applied either alone or together with IBDV vaccine and demonstrate certain prevention and immunoenhancement action.