Effects of corn grain processing and phosphorus content in calf starters on intake, growth performance, nutrient digestibility, blood metabolites, and urinary purine derivatives

作者：Masoumeh Eghtedari, A. Khezri, M. Kazemi‐Bonchenari, M Yazdanyar, Mohammadreza Mohammadabadi, S.E. Mahani, Mohtasham Ghaffari · 发表于：Journal of Dairy Science · 年份：2024 · DOI：10.3168/jds.2024-25079 · 被引用次数：6 · 研究领域：Ruminant Nutrition and Digestive Physiology、Crop Yield and Soil Fertility、Phosphorus and nutrient management

Corn grain with a high phosphorus (P) content (mainly in the form of phytate-P) may need to be processed to improve the digestibility of nutrients for young calves. Processing corn grains can improve the accessibility of phytate-P to the rumen enzymes and increase the bioavailability of P, which benefits the growth and development of calves. The objective of this study was to investigate the effects of feeding starter diets with steam-flaked corn (SFC) compared with ground corn (GC) with 2 P contents of 0.4% and 0.7% DM basis on intake, growth performance, nutrient digestibility, blood metabolites and urinary purine derivatives (PD) in dairy calves. A total of 48 female Holstein dairy calves (3 d old; average initial weight 39.7 ± 3.9 kg) were randomly assigned to a 2 × 2 factorial arrangement of treatments (12 calves/treatment) in a randomized complete block design. The treatment groups were: (1) a starter diet of GC with 0.4% P (GC-0.4P); (2) a starter diet of GC with 0.7% P (GC-0.7P); (3) a starter diet of SFC with 0.4% P (SFC-0.4P); (4) a starter diet of SFC with 0.7% P (SFC-0.7P). Calves received 6 L/d of transition milk on d 2 to 3 and 5 L/d of whole milk on d 4 to 30, which was increased to 7 L/d on d 31 to 45, then decreased to 5 L/d on d 46 to 60 and reduced to a single feeding of 2 L on d 61 to 62. All calves had free access to starter feed and water. All calves were weaned on d 63 and remained in the study until d 83. Rumen fluid samples were collected on d 38 (pre...