Measurement of porcine faecal IgA, IgG and IgM levels by a competitive enzyme-linked immunosorbent assay.

The concentrations of IgG, IgA and IgM were compared in faecal material of healthy and diarrhoeic pigs using a competitive enzyme-linked immunosorbent assay (ELISA). The relative concentrations of faecal immunoglobulins (Ig) in healthy piglets and adults were significantly different (P less than 0.01). IgA was the most important Ig in adult faeces while IgM was predominant in piglet faeces. IgG appears to be a relatively rare component. No significant differences could be detected between groups of healthy and diarrhoeic piglets. In adult faeces, significant changes (P less than 0.02 to P less than 0.001) in Ig relative concentrations were observed between diarrhoeic and healthy animals.