Risk Factors for Bulk Tank Milk Fat Depression in Northeast and Midwest U.S. Dairy Herds Feeding Monensin

Abstract

Farm gate milk prices in the US are based on milk components, including fat. Of these components, fat is most easily altered quickly. Understanding management strategies to influence milk fat percentage (MFP) is therefore useful. The biohydrogenation theory of milk fat depression (MFD) has improved our comprehension; however, many of the ruminal conditions that can result in MFD are not clearly understood. The objectives of this study were to investigate nutritional risk factors associated with bulk tank MFD and to characterize the fatty acid profile of bulk tank milk in relation to MFP in herds feeding monensin in the northeast and midwest US.