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) part...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
BMC
2019-06-01
|
| Series: | Journal of Animal Science and Biotechnology |
| Subjects: | |
| Online Access: | http://link.springer.com/article/10.1186/s40104-019-0356-3 |
| _version_ | 1811212709880922112 |
|---|---|
| author | Yunyi Xie Zezhong Wu Diming Wang Jianxin Liu |
| author_facet | Yunyi Xie Zezhong Wu Diming Wang Jianxin Liu |
| author_sort | Yunyi Xie |
| collection | DOAJ |
| description | 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 < 0.05) than the high RFI cows, but they produced similar energy-corrected milk. The ratios of milk to DMI (1.41 vs. 1.24, P < 0.01) and energy-corrected milk to DMI (1.48 vs. 1.36, P < 0.01) were greater in low RFI cows than those in the high RFI cows. The low RFI cows had lower milk urea nitrogen than that in the high RFI cows (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 < 0.05) and a higher partition of feed N to milk N (29.7% vs. 26.5%, P < 0.05). Conclusions The 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. |
| first_indexed | 2024-04-12T05:33:39Z |
| format | Article |
| id | doaj.art-bc0c2f2bbc5c4a958fc2769c3ccb654e |
| institution | Directory Open Access Journal |
| issn | 2049-1891 |
| language | English |
| last_indexed | 2024-04-12T05:33:39Z |
| publishDate | 2019-06-01 |
| publisher | BMC |
| record_format | Article |
| series | Journal of Animal Science and Biotechnology |
| spelling | doaj.art-bc0c2f2bbc5c4a958fc2769c3ccb654e2022-12-22T03:45:57ZengBMCJournal of Animal Science and Biotechnology2049-18912019-06-011011810.1186/s40104-019-0356-3Nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intakeYunyi Xie0Zezhong Wu1Diming Wang2Jianxin Liu3Institute of Dairy Science, MOE Key Laboratory of Molecular Animal Nutrition, College of Animal Sciences, Zhejiang UniversityInstitute of Dairy Science, MOE Key Laboratory of Molecular Animal Nutrition, College of Animal Sciences, Zhejiang UniversityInstitute of Dairy Science, MOE Key Laboratory of Molecular Animal Nutrition, College of Animal Sciences, Zhejiang UniversityInstitute of Dairy Science, MOE Key Laboratory of Molecular Animal Nutrition, College of Animal Sciences, Zhejiang UniversityAbstract 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 < 0.05) than the high RFI cows, but they produced similar energy-corrected milk. The ratios of milk to DMI (1.41 vs. 1.24, P < 0.01) and energy-corrected milk to DMI (1.48 vs. 1.36, P < 0.01) were greater in low RFI cows than those in the high RFI cows. The low RFI cows had lower milk urea nitrogen than that in the high RFI cows (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 < 0.05) and a higher partition of feed N to milk N (29.7% vs. 26.5%, P < 0.05). Conclusions The 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.http://link.springer.com/article/10.1186/s40104-019-0356-3Lactating cowsMicrobial proteinNitrogen partitioningResidual feed intake |
| spellingShingle | Yunyi Xie Zezhong Wu Diming Wang Jianxin Liu Nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intake Journal of Animal Science and Biotechnology Lactating cows Microbial protein Nitrogen partitioning Residual feed intake |
| title | Nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intake |
| title_full | Nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intake |
| title_fullStr | Nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intake |
| title_full_unstemmed | Nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intake |
| title_short | Nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intake |
| title_sort | nitrogen partitioning and microbial protein synthesis in lactating dairy cows with different phenotypic residual feed intake |
| topic | Lactating cows Microbial protein Nitrogen partitioning Residual feed intake |
| url | http://link.springer.com/article/10.1186/s40104-019-0356-3 |
| work_keys_str_mv | AT yunyixie nitrogenpartitioningandmicrobialproteinsynthesisinlactatingdairycowswithdifferentphenotypicresidualfeedintake AT zezhongwu nitrogenpartitioningandmicrobialproteinsynthesisinlactatingdairycowswithdifferentphenotypicresidualfeedintake AT dimingwang nitrogenpartitioningandmicrobialproteinsynthesisinlactatingdairycowswithdifferentphenotypicresidualfeedintake AT jianxinliu nitrogenpartitioningandmicrobialproteinsynthesisinlactatingdairycowswithdifferentphenotypicresidualfeedintake |