A NOVEL DEVELOPMENTAL PROCESS OF INTESTINAL EPITHELIAL LESIONS IN A CALF INFECTED WITH ATTACHING AND EFFACING ESCHERICHIA-COLI

A comparative study on the adhesion of attaching and effacing Escheric hia coil (AEEC) to the enterocytes between the colon of a calf and the jejunum of a piglet showed differences in the developmental process o f attaching and effacing (AE) lesions. In the calf, pedestals consiste d of fused microvilli, while in the piglet they developed from the api cal epithelial cell membranes after effacing microvilli. Microvilli ad jacent to the AEEC attachment site were atrophic in the calf, whereas they were elongated in the piglet. The production of AE lesions in the calf may be indicative of a novel developmental process with AEEC inf ection.