Dataset Information

Nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intake.

ABSTRACT:

Background

Residual feed intake (RFI) is an inheritable measure of feed efficiency that is independent on level of production. However, physiological and metabolic mechanisms underlying divergent RFI are not fully elucidated. This study was conducted to investigate dietary nitrogen (N) partitioning and microbial protein synthesis in lactating dairy cows divergent in phenotypic RFI.

Results

Thirty Holstein dairy cows (milk yield?=?35.3?±?4.71?kg/d; milk protein yield?=?1.18?±?0.13?kg/d; mean?±?standard deviation) were selected for the experiment to derive RFI. After the RFI measurement period of 50 d, the 10 lowest RFI cows and 8 highest RFI cows were selected. The low RFI cows had lower dry matter intake (DMI, P?P?P?P?=?0.05). Apparent digestibility of nutrients did not differ between two groups (P?>?0.10). Compared with high RFI animals, the low RFI cows had a lower retention of N (5.72 vs. 51.4?g/d, P?P?ConclusionsThe results suggest that differences in N partition, synthesis of microbial protein, and utilization of metabolizable protein could be part of the mechanisms associated with variance in the RFI.

SUBMITTER: Xie Y

PROVIDER: S-EPMC6580507 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intake.

Xie Yunyi Y Wu Zezhong Z Wang Diming D Liu Jianxin J

Journal of animal science and biotechnology 20190614

<h4>Background</h4>Residual feed intake (RFI) is an inheritable measure of feed efficiency that is independent on level of production. However, physiological and metabolic mechanisms underlying divergent RFI are not fully elucidated. This study was conducted to investigate dietary nitrogen (N) partitioning and microbial protein synthesis in lactating dairy cows divergent in phenotypic RFI.<h4>Results</h4>Thirty Holstein dairy cows (milk yield = 35.3 ± 4.71 kg/d; milk protein yield = 1.18 ± 0.13 ...[more]

PMID: 31236271

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Dataset Information

Nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intake.

Background

Results

Publications

Nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intake.

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