Ruminoreticular motility in ewes during pregnancy and lactation.

The frequency of primary cycle ruminoreticular movements was measured in ten ewes during pregnancy and lactation, in three ewes during pregnancy and in two non-pregnant ewes. The frequency, of one movement every 76 seconds during non-pregnancy and up to months 2 of pregnancy increased during later pregnancy and lactation to a peak of one every 58 seconds during the second month of lactation. This increase might explain the increased rate of passage of foodstuff through the digestive tract of sheep during pregnancy.