Research Of Preventive Effect Of Complex Traditional Chinese Medicine "Qin Kang San" On Artificial Infected Chicken By Newcastle Disease Virus(NDV)

In order to observe the prophylactic effect of complex traditional Chinese medicine "Qin Kang San" on chicken artificial infected by Newcastle disease virus(NDV),the anti-virus experiments in vitro and prophylactic trial in vivo of chick embryo were hold respectively.10 days old chick embryo were grouped random into tranditional Chinese medicine precaution group(Low dosage,middle dosage,high dosage),negative control,positive control(8 chick embryos per group).In the tranditional Chinese medicine precaution groups,allantoic cavity of ever chick embryo was injected into 0.1mL medicine extract with different dilution as 0.25g/mL,0.5g/mL,1g/mL.1 hours later,0.1mL Newcastle disease virus were inoculated,while 0.2mL physiological saline in negative control group and 0.2ml dilution of NDV-F48E9 100 times ELD₅₀ in positive control group. Then the depressant effect of complex traditional Chinese medicine on chicken infected by NDV was observed.400 Leshan-chicken hybrids(without inoculated by NDV vaccine) of 10 days old were randomly grouped into 5 negative control group(non-conteracting toxic substances+basal diet),positive control group(conteracting toxic substances+basal diet),positive control group also with basal diet but conteracting toxic substances.Low dosage group(conteracting toxic substances+basal diet+0.5%"Qin Kang San"),middle dosage group(conteracting toxic substances+basal diet+1%"Qin Kang San"),high dosage group(conteracting toxic substances+basal diet+2%"Qin Kang San")Low dosage group was dealed the same as positive control group except adding 0.5%"Qin Kang San" while 1%"in middle group and 2%in high group.8 repetitions per group(3 repetitions in 8 were used to observe morbidity and mortality),10 chicken per repetition.17 day old, the chicken were persistently feed with tranditional Chinese medicine diet for 5 daysto 22 day old.Then inoculate NDV.The clinical manifestation and death were observed and recorded daily;The following data such as immune globulin of peripheral blood,ND-HI antibody titer,index number of immune organ,T cell subgroup of peripheral blood,the immune function of red blood cells were recorded respectively in the day before feeding with medicine,the fifth day and 1d,3d,7d and 11d after inoculated by NDV.The results showed that:1.Livability of chick embryo in the tranditional Chinese medicine precaution group(0.25g/mL,0.5g/mL and 1g/mL) were 37.5%,62.5%and 100%.Negative were 100%and chick embryoes in positive group were died in 96h.It showed that "Qin Kang San" has the obvious effect on anti-NDV F48E9 1 g/mL was the best dosage.2.Incidence rate in the tranditional Chinese medicine precaution group with 0.5%,1.0%and 2.0%was 16.7%,10%and 26.7%,the death rate was 6.7%,3.3%and 20% respectively.Both incidence and death rate were 0 in negative control group while 100% incidence rate and 66.7%death rate in positive control group.What showed that "Qin Kang San" has the distinct precaution to the NDV in the chicken by artificial infection.It could degrade the morbidity and mortality obviously 1.0%was the best dosage.3."Qin Kang San" could prevent effectively the damage of NDV to chicken's immune organ such as thoracic gland,bursa of Fabricius.It could also upgrade the immune organ index,decreasing the level of antibody tire by NDV inoculation. increasing the contents of CD3⁺,CD4⁺ and the ratio of CD4⁺/CD8⁺.upgrading the contents of IgA,IgG and IgM.Promoting the immune function of red blood cell.So, The cellular immune function and humoral immune function of chicken were increased distinctively.the ability of anti-virus was strengthened accordingly.The 0.5%～1.0%had the biggest leaven.4."Qin Kang San" has the distinct precaution to the NDV in the chicken by artificial infection.0.5%～1.0%was the best.