Intestinal permeability to macromolecules during colibacillosis in piglets.

Intestinal macromolecular permeability to macromolecules was determined in a group of specific pathogen free piglets before and after they were infected experimentally with Escherichia coli. Six hours after the infection all piglets developed a profuse diarrhoea. The urea and total protein concentrations in the serum increased markedly after the onset of diarrhoea. Haemoglobin concentration and PCV decreased steadily during the experiment but blood glucose concentration and lipid composition of the faeces did not change. No structural abnormalities in the jejunal and ileal mucosa were seen. No uptake of macromolecules (40,000 KDa) was found suggesting that molecules with a molecular weight of 40,000 or more do not play a role in the persistent diarrhoea sometimes seen in piglets after colibacillosis.