Effect Of Modified Qingdai Powder On Feline Calicivirus Infection

Feline calicivirus infection is a viral infectious disease caused by feline calicivirus（FCV）.The clinical manifestations are fever,oral ulcers,sneezing,eye and nose secretions,conjunctivitis and so on.Feline calicivirus is prevalent worldwide,mostly in places where cats gather.At present,there is no specific medicine for feline calicivirus infection,and there is no ideal vaccine in China.Interferon and antibiotics are commonly used in clinical treatment,but the therapeutic effect is not ideal.Modern pharmacological studies have proved that Chinese medicine has good antibacterial and antiviral effects.Indigo Naturalis Powder,first seen in Wuzhiwang’s"Jiyang Compendium",is composed of Indigo Naturalis,Coptis,Cork,Peppermint,Platycodon grandiflorum,and catechu.It has the effects of clearing away heat and detoxifying,relieving lungs and relieving cough,eliminating phlegm and pus,and astringent muscle growth.At present,there is no report on the therapeutic effect of Qingdai powder in the treatment of cat calicivirus infection.Therefore,this experiment established a stable feline calicivirus infection model to explore the therapeutic effect of Qingdai powder on cat calicivirus infection.Provide a new method for the treatment of cat calicivirus infection.A stable feline calicivirus infection model was established by inoculating cats aged 6-12 months with 1 mL FCV virus solution of 10^9.67 TCID₅₀/mL by nasal drops.48 hours after infection,the experimental cat will have clinical symptoms such as fever,and pathological changes in the tonsils and lungs.After successfully establishing the feline calicivirus infection model,the effective dose of Qingdai powder was screened.Set three different doses of Qingdai powder treatment groups,namely high-dose（2 g/kg）treatment group（n=4）,middle-dose（1 g/kg）treatment group（n=4）and low-dose（0.5 g/kg）treatment group（n=4）.The clinical symptom score,body temperature,body weight,necropsy and histopathological changes were used as indicators of treatment effect.The results show that the various dose groups of Qingdai powder have varying degrees of therapeutic effect on cat calicivirus infection.The middle dose group of Qingdai powder（1 g/kg）treatment had the best therapeutic effect,which could significantly reduce clinical symptoms and pathological changes of tonsils.The expression levels of IL-1β,IL-6 and IFN-γwere measured for the blank control group,model group,Qingdai powder high,medium and low dose groups and model group.The results showed that IL-6 increased significantly after the cat was infected with FCV After treatment,the IL-1βand IFN-γin the middle-dose（1 g/kg）treatment group of Qingdai powder increased significantly.Finally,8 clinical cases were collected,and on the basis of the above experiments,1 g/kg Qingdai powder was used for treatment.In clinical treatment,Qingdai powder has a good therapeutic effect,and the effective rate can reach 87.5%.The results show that Qingdai powder has the potential to become a clinical drug for treating cat calicivirus infections.