Intake Limitations, Feeding Behavior, and Rumen Function of Cows Challenged with Rumen Fill from Dietary Fiber or Inert Bulk

摘要: Abstract Twelve multiparous, rumen, cannulated cows (17 DIM) were fed 25 or 35% NDF diets without with added rumen-inert bulk as water-filled plastic containers (500 ml each) within three 4 × Latin squares (21-d periods). Added equaled 25% of pretrial rumen volume for each cow. Objectives to challenge fill in the form dietary and inert determine whether affects intake similarly different content changes behavior function allow adapt higher fill. Inert had no effect on DMI but decreased (18.7 vs. 16.6 kg/d). Volume digesta plus bulk, 102 L, was similar treatment regardless presence absence bulk. Additional increased number ruminating bouts per day, chewing time unit intake, frequency reticular contractions during rumination, fractional passage rate from rumen. Although these may help alleviate fill, they insufficient maintain under conditions high Intake by receiving fiber can be limited reticulorumen capacity. Future study is required digestion, particle size, animal characteristics fill-limited intake.