Abstract: | Heat-stable enterotoxin (STa) from Escherichia coli strain 431 was injected into the jejunum of 4 pigs from each of 3 litters, using a ligated intestinal loop assay (with loops beginning 1 m caudad to the pylorus). The jejunum was divided into 4 contiguous areas, with 4 loops in each area. Doses of 0, 10, 100, or 1,000 ng of purified toxin (10 ng/mouse unit) were injected into the loops within an area, using a 4 X 4 Latin square design. Fluid accumulation in the loops increased (P less than 0.05) with increasing concentrations of STa in pigs in all litters, but the magnitude of the response varied across litters. Fluid responses to the STa varied in the different areas of the jejunum, with pigs in 2 litters having a decrease (P less than 0.05) in the response to STa in the caudal areas. These data quantitate the variability within the different areas of the jejunum of the young pig. |