Here’s more evidence that you need to pay attention to your grouping strategies for dry cows.
Canadian researchers recently took at look at the effect of regrouping during the dry period on feeding, social, rumination and lying behavior for cows that were moved to a new pen and cows that remained in their home pen but had new cows introduced.
Results published in the May Journal of Dairy Science show that cows that were moved to a new pen after regrouping decreased dry matter intake by approximately 9 percent on the day of regrouping compared with baseline values, but cows that remained in their home pen showed no significant decrease in intake after regrouping. Feeding rate decreased in both treatments by 10 percent after regrouping. Rumination times also decreased by approximately 9 percent in both treatments, reaching the lowest values on the day of regrouping for cows that stayed in the home pen and on the day after regrouping for the moved cows.
Cows that were moved to a new pen displaced other cows at the feeder twice as frequently after regrouping, but no such effect of regrouping on cows that stayed in the home pen was observed. Therefore, take note that regrouping often affects behavior of pre-partum dairy cows, especially those cows that are moved to a new pen.