Added Dietary Fat for Milk and Fat Production in Commercial Dairy Herds

A high-fat protein supplement was incorporated into complete mixed diets of lactating dairy cows in six commercial dairy herds of group-fed animals in free stall housing. Fat content of the total dietary dry matter was increased from approximately 3% to approximately 6%. When high-fat diets were fed, daily milk production of high producing Holstein cows increased 1.4 kg/day, and milk fat decreased .2 percentage units. There was no change in daily milk production in low producing Holstein cows; however, they decreased in milk fat percent when fed the high-fat diet. Milk protein percent was not changed by feeding the high-fat diet.