Anti-porcine circovirus type 2 （PCV2） antibody placental barrier leakage from sow to fetus： impact on the diagnosis of intra-uterine PCV2 infection

Dear Editor,Fetuses develop antibodies when they are infectedwith porcine circovirus type 2(PCV2).At abortion orbirth,both PCV2 and/or anti-PCV2 antibodies can thenbe detected.Finding anti-PCV2 antibodies in aborted fe-tuses or stillborn piglets is generally used as evidence ofan intra-uterine PCV2 infection.However,a recent anal-ysis of fetuses sent in for PCV2 diagnosis and caesare-an-derived,colostrum-deprived pigs revealed that low