Two-dimensional electrophoresis protein patterns of N. caninum (Nc-1) tachyzoites separated using 12% acrylamide and visualised by silver staining. A total of 70 immunoreactive protein spots (spot numbers 1–70) were identified on the 2-DE gel based on immunoblot analysis that were recognised by known bovine sera. The circle or ellipse with arrows indicates 20 specific protein spots that were recognised by N. caninum-positive bovine pooled sera.