Effect of succulent and nonsucculent diets on rumen motility and pressure before, during, and after eating.

Rumen motility was measured in cattle by recording changes in rumen pressure through a rumen cannula. Irrespective of diet, eating increased rumen motility and amplitude of primary rumen contractions. Succulent, readily fermentable, and nonscabrous alfalfa tops fed alone or with oat hay produced a greater frequency of primary and secondary rumen contractions than oat hay fed alone. The intrarumen pressure was also greater when alfalfa tops were fed. Oat hay in the diet caused primary rumen contractions of a greater amplitude than when alfalfa tops were fed alone. Correlations were positive between frequency of primary and secondary rumen contractions and intrarumen pressure.