Leal L N, Daniel J B, Doelman J, Keppler B R, Steele M A, Martín-Tereso J
Trouw Nutrition Research and Development, Amersfoort, the Netherlands 3800 AG.
Trouw Nutrition Research and Development, Amersfoort, the Netherlands 3800 AG.
J Dairy Sci. 2025 Jun;108(6):5875-5888. doi: 10.3168/jds.2024-26102. Epub 2025 Apr 11.
This study aimed to investigate the effects of preweaning nutrient intake on milk production in the 2 first lactations, risk of culling, and metabolomic profiles of dairy cows fed a restricted (RES) or an elevated (ELE) milk supply preweaning. A total of 86 female Holstein Friesian calves were randomly assigned to either 5.4 Mcal of ME in 8 L of milk replacer (MR) per day (ELE) or 2.7 Mcal of ME in 4 L of MR per day (RES) from d 2 after birth until they were stepped down by 50% from d 42 to d 49 and fully weaned at d 50. Starting from d 50, animals from both treatment groups were fed and managed in the same way, with treatments being blinded, for the entire study duration. At 60 DIM in the first lactation, blood samples were taken for metabolomic analysis. Heifers fed the ELE diet exhibited higher ADG (0.79 vs. 0.49 kg/d) in the preweaning period, leading to higher BW at 70 d of age (94 vs. 85 kg). In the first lactation, cows fed the ELE diet preweaning exhibited higher DMI (+0.7 kg/d), higher milk fat yield (+50 g/d), and higher milk fat content (+0.24%) but lower feed efficiency (-0.04) than cows in the RES group. In the second lactation, fat- and protein-corrected milk yield (+1.8 kg/d), milk fat yield (+115 g/d), milk fat content (+0.22%), and feed efficiency (+0.06) were all higher in ELE cows. Throughout these 2 lactations, ELE cows were leaner, as indicated by a lower BCS. Cows fed the ELE diet preweaning had a higher first-service conception rate during the second lactation than cows fed the RES diet (40.7% vs. 13.0%). Moreover, the likelihood to be culled before third, fourth, or fifth calving was halved when calves were fed ELE compared with RES. Metabolomic profiling revealed distinct metabolomic profiles at 60 DIM in response to preweaning milk supply. The major metabolic pathways affected by preweaning nutrient supply at 60 DIM were pyrimidine, sphingosine, guanidino, acetamido, and purine metabolism and the tricarboxylic acid cycle. The metabolic profile differences between the groups describe a metabolic configuration that was sustained into adulthood and that may explain the improved productivity and resilience of cows fed a greater milk supply during the preweaning period.
本研究旨在调查断奶前营养摄入量对奶牛头两胎产奶量、淘汰风险以及代谢组学特征的影响，这些奶牛在断奶前分别采用限制（RES）或增加（ELE）的牛奶供应量。总共86头荷斯坦弗里生小母牛在出生后第2天被随机分配，一组每天饲喂8升代乳粉（MR），其中含5.4兆卡代谢能（ELE），另一组每天饲喂4升MR，含2.7兆卡代谢能（RES），直至从第42天到第49天供应量减少50%，并在第50天完全断奶。从第50天开始，两个处理组的动物在整个研究期间以相同方式饲养和管理，处理过程设盲。在第一个泌乳期的第60天，采集血样进行代谢组学分析。饲喂ELE日粮的小母牛在断奶前期表现出更高的平均日增重（0.79 vs. 0.49千克/天），导致70日龄时体重更高（94 vs. 85千克）。在第一个泌乳期，断奶前饲喂ELE日粮的奶牛与RES组奶牛相比，表现出更高的干物质采食量（+0.7千克/天）、更高的乳脂产量（+50克/天）和更高的乳脂含量（+0.24%），但饲料效率更低（-0.04）。在第二个泌乳期，ELE组奶牛的脂肪和蛋白质校正乳产量（+1.8千克/天）、乳脂产量（+115克/天）、乳脂含量（+0.22%）和饲料效率（+0.06）均更高。在这两胎泌乳期内，ELE组奶牛体况评分较低，表明更瘦。断奶前饲喂ELE日粮的奶牛在第二个泌乳期的首次配种受胎率高于饲喂RES日粮的奶牛（40.7% vs. 13.0%）。此外，与RES组相比，饲喂ELE的犊牛在第三次、第四次或第五次产犊前被淘汰的可能性减半。代谢组学分析显示，在第60天，根据断奶前牛奶供应量不同，代谢组学特征存在明显差异。在第60天，受断奶前营养供应影响的主要代谢途径有嘧啶、鞘氨醇、胍基乙酸、乙酰氨基和嘌呤代谢以及三羧酸循环。两组之间的代谢特征差异描述了一种持续到成年期的代谢模式，这可能解释了断奶前期饲喂更多牛奶的奶牛生产力和恢复力提高的原因。
