GP2 and pelvic inflammatory disease: The IgA Ab response to Wa HRV in serum samples started at 14 PID and was closely followed by IgG Abs, except for piglets in Gp2 (Wa HRV IgY 4096) that did not have IgA Abs at 14 PID but still had IgM Abs at this experimental time point, a profile that remained until the end of the experiment (Figure 3).