1. Optimizing dietary rumen-degradable starch to rumen-degradable protein ratio improves lactation performance and nitrogen utilization efficiency in mid-lactating Holstein dairy cows
- Author
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Panliang Chen, Yan Li, Meimei Wang, Yizhao Shen, Mingchao Liu, Hongjian Xu, Ning Ma, Yufeng Cao, Qiufeng Li, Mahmoud M. Abdelsattar, Zhiyuan Wang, Zihan Huo, Shuai Ren, Linqi Hu, Jie Liu, Yanxia Gao, and Jianguo Li
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rumen-degradable starch ,rumen-degradable protein ,lactation performance ,nitrogen utilization efficiency ,Holstein dairy cows ,Veterinary medicine ,SF600-1100 - Abstract
The dietary rumen-degradable starch (RDS) to rumen-degradable protein (RDP) ratio, denoted as the RDS-to-RDP ratio (SPR), has been proven to enhance in vitro rumen fermentation. However, the effects of dietary SPR in vivo remain largely unexplored. This study was conducted to investigate the effect of dietary SPR on lactation performance, nutrient digestibility, rumen fermentation patterns, blood indicators, and nitrogen (N) partitioning in mid-lactating Holstein cows. Seventy-two Holstein dairy cows were randomly assigned to three groups (24 head/group), balanced for (mean ± standard deviation) days in milk (116 ± 21.5), parity (2.1 ± 0.8), milk production (42 ± 2.1 kg/d), and body weight (705 ± 52.5 kg). The cows were fed diets with low (2.1, control), medium (2.3), or high (2.5) SPR, formulated to be isoenergetic, isonitrogenous, and iso-starch. The study consisted of a one-week adaptation phase followed by an eight-week experimental period. The results indicated that the high SPR group had a lower dry matter intake compared to the other groups (p
- Published
- 2024
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