A Case of Starch Overload in Young Dairy Heifers: A Physiological and Nutritional Point of View

In order to guarantee sufficient growth, digestive stability, and long-term productivity in dairy heifers, proper nutritional management is crucial both before and after weaning. This case study assesses the impact of dietary modifications on growth performance and digestive parameters in commercial settings and details a field observation of concentrate overload in young Holstein heifers. From 77 to 165 days of age, the body weight (BW), average daily gain (ADG), body condition score (BCS), feed intake, and fecal characteristics of 15 calves were monitored. Infectious and parasitic causes of diarrhea were ruled out by fecal examinations. Ad libitum concentrate feeding resulted in low fecal scores with undigested grain particles and acidic smell, starch intake exceeding requirements, and concentrate intake reaching up to 6 kg as fed head×day. The BCS gradually rose, and ADG peaked at 1.64 kg/day. Forage intake increased, fecal consistency improved, and ADG stabilized after restricting concentrate allowance to 2.5% of BW. These results underline the significance of controlling starch intake and concentrate allowance to avoid excessive growth and digestive disorders in developing dairy heifers, and they support a nutritional basis for the observed digestive imbalance.