Evaluation of the respective relationships between rumination time within the first 10 days in milk and periparturient diseases, subclinical hypocalcemia, negative energy balance, and milk production in dairy cows

Abstract

Healthy dairy cows ruminate approximately 400 to 500 minutes per day; however, rumination time can be affected by several factors such as diet composition, health status, environment, and stress. Increased rumination time can be associated with increased health because of increased saliva production, whereas decreased rumination time has been associated with negative health effects. Historically, evaluating rumination time was laborious and limited to a few animals at a time; however, adoption of new technology like rumination collars has allowed increased data collection and monitoring of rumination time at both the individual and herd level. The effect of rumination time early in the postpartum period, based on rumination collar data, on milk production has not been thoroughly evaluated. The objectives of this pilot study were to evaluate the maximum number minutes per day spent ruminating during the first 10 days-in-milk (DIM) for cows that developed displaced abomasum (DA), clinical ketosis (CK), subclinical hypocalcemia, or excessive negative energy balance, and to evaluate the association between rumination minutes and total milk production during the first 30 DIM after controlling for potential confounders.