The cows were assigned to one of four groups. Three of the groups contained five cows each; the fourth group contained six cows. The groups were randomly assigned to one of the four experimental treatments, to which they were exposed for 1 week. Following the first experimental week, all of the cows were given fresh water for a week to ensure that they were fully hydrated at the beginning of the next experimental week. This was necessary, because water intake was negatively affected during the first experimental week. For the start of the second experimental week, the groups were reassigned to treatments different from those during the first experimental week. The cattle were offered water ad libitum, and daily consumption was determined for each heifer. The amount of unconsumed water was determined each morning, the troughs were emptied, and fresh water and treatments were added. The heifers were weighed at the end of the trial.