Motor functions of the large intestine in sheep versus cattle.

The electrical activity of the caecum and of the different parts of the colon was recorded from chronically implanted electrodes in the ovine and bovine species, the latter including cattle and calves before and after weaning. In the both species, colonic spiking activity consisted of spike bursts lasting from 5 to 13 s localized to the caecum and proximal colon, and of spike bursts lasting 3 to 8 s, localized to the spiral colon. An intermingled pattern of long and short spike bursts was recorded on the distal colon in sheep but not in cattle. Another major difference between the two species was a permanent short spike burst activity in the ovine spiral colon (95 versus 25% of the recording time in cattle). Periods of continuous spiking activity lasting 6 min, migrated from the proximal colon to the distal colon in the cows and calves but not in sheep. The role of the different patterns of colonic activity is discussed in terms of colonic motor functions involved in the formation of faeces.