Ultrasonographic examination of the caecum and the proximal and spiral ansa of the colon of cattle

The large intestine of 10 cows was examined from the right abdominal wall w ith a 3.5 MHz linear transducer. The cows were then slaughtered, and the or gans were re-examined in a water bath. The caecum was visualised from the m iddle region of the abdominal wall. it ran caudo-cranially, varied in diame ter from 5.2 to 18.0 cm and was situated immediately adjacent to the abdomi nal wall. The lateral wall of the caecum appeared as a thick, echogenic, cr escent-shaped line. it could be visualised as far cranially as the 12th int ercostal space. Although its junction could not be identified, the proximal ansa of the colon was recognised on the basis of its anatomical position a nd its diameter, which was smaller than that of the caecum. The spiral ansa of the colon and the descending colon were situated dorsal to the caecum a nd could be identified by moving the transducer horizontally along the abdo minal wall to the last rib. The spiral ansa of the colon was situated ventr al to the descending colon, and its walls appeared as thick echogenic lines . In a contracted state, the spiral colon had the appearance of a garland.