Pre- and postweaning feeding strategies on growth and digestion of female Holstein calves

calves consumed more nutrients and achieved greater BW and BCS at 5 mo. No interactions among preweaning and postweaning feeding strategies were detected for body growth or diet digestibility. However, significant interactions were observed for nitrogen metabolism and ruminal fermentation shortly after weaning. Increased MR allowance enhanced nutrient supply and preweaning growth without compromising postweaning digestibility, reinforcing cumulative starter intake as the primary driver of digestive development. Restricted calves tended to retain more nitrogen and reached BW comparable to those fed greater MR when provided higher postweaning nutrition, highlighting compensatory growth. These results emphasize the importance of aligning pre- and postweaning feeding strategies to support physiological adaptation and optimize developmental outcomes of dairy heifers under postweaning forage-based diets.