Analysis of antigenicity of purified VLPs using RVC immune Gn piglet sera Ab ELISA and antibody titers in gilts/sows milk and serum samples. A Antigenicity of purified RVC VLPs was tested using serum from Gn piglets inoculated with G1, G3 or G6 porcine RVC strains in a VLP-based indirect Ab ELISA. Cowden serum was collected at PID 21 while G3 and G6 serum were collected at PID 10. Negative control serum was collected prior to virus inoculation. B, C Cocktail mixture of VLPs (Table 2) was used as antigens in an RVC VLP-based indirect Ab ELISA. Milk and serum from sows/gilts with diarrheic or healthy piglets (fourfold serial dilutions 1:25, 1:400, 1:1600 and 1:6400) were tested for RVC IgA (B) and IgG (C) Ab titers. D Comparative analysis of milk IgA antibody titers in all sows and gilts. E Comparative analysis of milk IgG antibody titers in all sows and gilts.