Effects of heated drinking water on the production responses of lactating Holstein and Jersey cows

Abstract

An experiment was conducted to evaluate the effect of heating the drinking water of lactating dairy cows in different ambient environments on the feed and water intake and milk yield and composition and hydration status of Jersey and Holstein cows. Eighteen cows were randomly assigned to either an ambient (7-15°C), or a continuously heated (30-33°C), drinking water treatment in a switchback design. The experiment was replicated four times [spring (24.4°C), summer (21.1°C), autumn (11.8°C), and winter (12.6°C)] in a tie-stall facility. Free water intake was 3.40-5.95% greater (P < 0.05) each time the heated versus ambient drinking water was supplied across all trials. Both breeds responded similarly. Feed intake was increased 4.47% (P < 0.001) when cattle were offered the heated water during the summer experiment. Milk yield was greater (P < 0.01) for the spring and summer (P < 0.05) experiments when cattle were consuming the ambient water treatment. Water treatment had no effect on milk components or hydration status. Cows consumed 40% of their daily water intake within 2 h of each milking and feeding time. The results of this experiment demonstrate that cows drank more warm water when offered, but the increase in free water intake did not influence milk yield.