Variation in and Relationships Among Feeding, Chewing, and Drinking Variables for Lactating Dairy Cows

摘要: Abstract Twelve Holstein cows (63 DIM; 6 primiparous) were offered a common diet and monitored for 21 d (11 of adaptation, 10 collection) with data acquisition system to measure continuously feed water intakes chewing behavior. Objectives examine relationships among feeding behavior variables noncompeting producing various quantities milk determine experimental designs adequate power detect reasonable treatment differences in future experiments. Coefficients variation across ranged from 5 41% the studied. Milk production was correlated positively DMI intake within parities. For multiparous cows, related meal size (r=.78) length eating bouts (r=.75) unrelated number rate. primiparous tended be (r=.55) rate (r=.87) size. Rumination total time spent per unit negatively (r=−.58) These correlations suggest that exist efficiency. Reasons why high consume chew more effectively deserve further study. Contrast 10% means examined had an 80% probability detection Latin square design utilizing 12 d.