Graduate Student Literature Review: Heat abatement strategies used to reduce negative effects of heat stress in dairy cows

摘要

The southeastern United States experiences anextended hot season with a high environmental temperatureand relative humidity. With increasing globaltemperatures, managing dairy cattle in regions withtropical, subtropical, and Mediterranean climates isbecoming an increasing challenge. Heat-stressed cowswill decrease feed intake, decrease productivity, andincrease respiration rate in an attempt to maintain internalbody temperature. Temperature-humidity index(THI) is a unitless value that has been used to measurethe magnitude of heat stress on dairy cows. Manyresearchers have studied the THI threshold at whichdairy cattle begin to experience heat stress. Whenhousing cows in a confinement setting, a pasture-basedsetting, or a combination of the two, the appropriateheat abatement should be implemented to allow cowsto perform to their potential and to improve overallanimal welfare. This review summarizes heat abatementstrategies that have been studied to reduce thenegative effects of heat stress.