Intestinal permeability to polyethylene glycol 4000 and porcine albumin in piglets infected with transmissible gastroenteritis virus.

The intestinal permeability of specific pathogen free piglets has been studied by measuring the concentration of 14C in the blood after oral administration of 14C polyethylene glycol (14C PEG, MW = 4000) and the concentration of 131I in the faeces after intraperitoneal administration of 131I porcine albumin (131I PA, MW = 68,000). The tests were performed one day before and up to two days after the piglets were infected with transmissible gastroenteritis (TGE) virus. Jejunal biopsies were taken from two piglets before the experimental infection, from two piglets 12 h after the experimental infection and from five piglets at the end of the experiment, 46 h after infection. Blood samples were taken six-hourly and faecal samples several times. Some piglets vomited before diarrhoea and loss of appetite started at 14 h after infection; the packed cell volume decreased before but increased after infection. Morphological examination showed hyperregenerative villous atrophy at 46 h after infection. There was no increase in the permeation of 14C PEG but there was a significant increase in the flux of 131I PA from the blood to the gut lumen.