Effect Of Fc-FnBPB-CIfA Subunit Vaccine On Bovine Mastitis Associated Staphylococcus Aureus

Mastitis is inflammation of breast or udder tissue usually due to infection.Bacterial infection of mammary gland is a major cause of mastitis in cattle.A variety of bacteria cause of mastitis.At present,more than 150 kinds of bacteria have been found.Staphylococcus aureus is the most common pathogen responsible of mastitis in cattle.The key roles in this process of bacterial adhesions such as fibronectin binding protein B(FnBPB)and clumping factor A(ClfA)have been well documented.Fc receptor is expressed in the mammary gland of pigs and ruminants,the FcRn binding to IgG fragment of Fc and participates in maintaining the dynamic balance of IgG.Therefore,this study is based on the past study of Staphylococcus aureus mastitis was prepared Fc-FnBPB-ClfA subunit vaccine.The vaccine mix with 1%LMS or ALUM.Thirty pregnant heifers were selected for their absence of anti Fc-FnBPB-ClfA-LMS and anti Fc-FnBPB-ClfA-ALUM.Three months before calving,they were separated into three groups(n=10).Two groups immune by Fc-FnBPB-ClfA-ALUM or Fc-FnBPB-ClfA-LMS first by muscle immune,and teat canal as boost immune.Another group were used as non-vaccinated controls.ELISA was used to measure the ability of the immune sera and milk.The results showed that the injection of Fc-FnBPB-ClfA-LMS(Group A),serum antibody titer was up to 1:1600 and the whey antibody titer was up to 1:400.Group B,serum antibody titer was up to 1:800 and the whey antibody titer was up to 1:200.Group C,serum antibody titer was up to 1:400 and the whey antibody titer was up to 1:200.After calving of 30d,45d,60d collected the milk samples.Use CMT to test milk samples.The majority of cattle in the immune group that somatic cell counts were between 0 to 2 0000 each milliliter.While the number of cattles in the control group that their somatic cell counts had exceeded 500000 each milliliter.The isolation rate of Staphylococcus aureus was 85%in cattles before immunization,and the rate of bacteria was reduced about 15%after immunization.The results of this study showed that immunization by muscle and teat canal was the best way to immune.And bFc-FnBPB-ClfA mix up with LMS to immune can stimulate the immune response of cattles.