Potential for Altering Energy Partition in the Lactating Cow

Abstract

Partitioning of nutrients in lactating cows is discussed in terms of processes requiring energy associated with maintenance and production with emphasis upon kinetic properties that determine patterns and rates of nutrient use and nutrient interactions. Rates of nutrient oxidation by tissues are determined largely by energy expenditures, concentrations of nutrients in blood, and relative affinities of tissues for nutrients. Patterns of nutrient use for production are determined by the same factors, but interactions among substrates and acute and chronic hormone actions are much more complex. Most of these can be explained on the basis of known metabolic regulatory mechanisms using appropriate simulation modeling techniques if appropriate kinetic data are available.