Ruminant chronophysiological management: an emerging bioscience

Abstract

The objective of this paper is to introduce, discuss, and delineate an emerging bioscience known as chronophysiological management. Most recent research discov- eries have promised physiological innovations in laboratory animals, humans, and livestock. Lactating ruminants have high intake and production levels above maintenance, and thus are exceptional models for studying evolutionary nutrition and physiology. The evolution of animals has led to specialized behaviors that involve mainly overnight rumination and primary daytime (sunrise and sunset) grazing and eating. Consequently, eating activity, rumen ecology, postrumen nutrient assimilation, and peripheral nutrient metabolism have developed unique diurnal and nocturnal rhythms. These physiological rhythms are known as circadian rhythms that lead animal endocrinology and metabolism. Most recent findings demonstrate that altering feeding timing alters postprandial patterns of feed intake, rumen fermentation, and peripheral metabolism in both intensively housed and grazing lactating cows. Evening instead of morning feeding has improved milk and milk energy production. These demonstrations contribute to creating an evolutionary bioscience that links animal nutritional and physiology to chronobiology. The emerging bioscience of ruminant chronophysiological management is the incorporation of chronophysiology into livestock practices. Different species will have their own special response to altered chronophysiological management. Such post- modern strategies will therefore be an interface of ruminant, nonruminant, and human ecologies.