Pools of Wa HRV specific porcine IgG Abs, VP6 specific and Wa HRV specific chicken egg yolk IgY Abs and control IgY Abs used for this experiment.

Twenty Lohmann Brown Classic laying hens were hyperimmunized with 107 UFF/ml of Wa HRV (G1, P1A [8]) each time and 10 hens were hyperimmunized with recombinant VP6, 7 times. Crude egg yolks were diluted in distillated water in a 1∶3 ratio and precipitated using ammonium sulfate. Sow serum was also salt-precipitated. The pellets were suspended in 10% of the original volume of egg yolk or sow serum in PBS. The protein concentration was determined by spectrophotometry (Abs 280 nm; NanoDrop ND-1000, USA). The chicken IgY and porcine IgG Ab titers to Wa HRV G1P[8] were determined by ELISA and VN assays before and after sterilization by filtration (0.22-mm-pore-size membrane filter; Millipore, USA). The total IgY concentration was determined by ELISA.