Blood parameters are important phenotypic metrics for individual antivirus capacity.To investigate the effects of polyinosinic:polycytidylic acid (Poly I:C) stimulation on porcine blood parameters,we made correlation and principal component analysis on porcine blood parameters before and after Poly I:C stimulation.A total of 392 experimental pigs were selected from a DurocErhualian F2 population.The blood samples from each pig were collected by jugular venipuncture on day 33 (the control group) and at 4 h after Poly I:C stimulation on day 35 (the treatment group).The results showed that NE%,LY and LY% were significantly correlated,and HCT% and RBC were significantly different before and after the stimulation.The PLT and PCT,which are the decisive indices of the first principal component in the blood platelet,were not significantly different before and after the stimulation.