Influence of Short- and Term Exposure to a Hot Environment on Rumen Passage Rate and Diet Digestibility by Friesian Heifers

摘要

Effects of short- and ling-term exposure to a hot environment on diet digestibility and rumen passage rate were studied in four, 10-mo-old Friesian heifers housed in a climatic chamber. The trial lasted 65 d. Twenty-five days were spent under thermal comfort (temperature-humidity index = 64), and 40 d were spent under hot conditions (temperature-humidity in- dex = 84). Three digestibility and rumen passage rate trials were performed during the 65 d.