Change Rules Of Piglet A Type Foot-and-Mouth Disease Maternal Antibody And Cytokines

Foot and mouth disease(FMD)is caused by Foot-and-mouth disease virus(FMDV)and affected cloven-hoofed animals with an acute,heat,and highly contagious infectious disease.The disease several times in the world outbreak of popular,resulting in huge political and economic losses.Newborns have an immature system,but can not well protect against infectious diseases.Maternal antibodies provide early protection for piglets,and the characteristics of the maternal placenta determine that maternal antibodies are transmitted through milk.However,maternal antibodies have two sides,that is,to protect the piglets from infection,but also interfere with the role of vaccine immunity.Therefore,it is important to explore the transmission and regulation of maternal antibody of swine foot and mouth disease,and to clarify the law of maternal and female antibody growth in piglets.It is of great significance for the rational development of vaccine program for swine foot and mouth disease.1.Antibody levels of type A foot and mouth disease in serum of 5 sows and 25 piglets were detected by liquid phase blocking ELISA and virus neutralization test.The results showed that there was almost no type A foot and mouth disease antibody in the serum of piglets before feeding colostrum,after 1 day of feeding colostrum,the level of antibody reached a peak and remained stable within 5 to 7 days,and then decreased gradually.This proves that the maternal antibody was transmitted to the piglets through colostrum.According to the antibody level and the deceleration rate,when the sow antibody level was 1: 1024,1: 720 and 1: 256,the most suitable time for immuning was 56,42 and 28 days old respectively in piglets.2.The changes of serum Ig G,Ig A and Ig M in serum and milk of umbilical cord were analyzed by ELISA.The results showed that the three kinds of immunoglobulin were abundant in sow serum and colostrum,and the serum and umbilical cord blood in piglets fed without colostrum were not Ig G,Ig A and Ig M.After 1 day of colostrum intake,the content of Ig G,Ig M,Ig A increased rapidly,and then Ig A and Ig G content showed a continuous downward trend,while the Ig M content continued to decline to about 42 d then substantial recovery.3.Antibody chips QAP-CYT-1 and QAP-CYT-2 were used to detect 20 cytokines in sow serum,milk and corresponding piglet serum.The results showed that 20 kinds of cytokines in sow serum and milk were rich in cytokines.Of which 8 kinds of cytokines(TNFa?TGFb1?IFNg?GM-CSF?IL-10?IL-6?IL-4?IL-1b)in the serum of piglets before feeding colostrum was not detected,but after the intake of colostrum,they were increasing significantly,indicating that the eight kinds of cytokines were passed through colostrum passively;The remaining 12 kinds of cytokines(CCL3L1?IFN??IL-1??IL-1ra?IL-13?IL-17A?MIG?IL-18?MIP-1b?PECEM-1?IL-8?IL-12P40P70)in the piglets before feeding colostrum serum already existed,but its content increasing after feeding colostrum,indicating that these 12 cytokines could also be passed through the colostrum to the piglets,but whether through the placenta,need further proof.