Effect of Varying Dietary Crude Protein Level on Feed Intake, Nutrient Digestibility, Milk Production, and Nitrogen Use Efficiency by Lactating Holstein-Friesian Cows

Simple item page
dc.contributor.authorKatongole, Constantine
dc.contributor.authorYan, Tianhai
dc.date.accessioned2021-01-20T11:52:58Z
dc.date.available2021-01-20T11:52:58Z
dc.date.issued2020-12-19
dc.descriptionPublication history: Accepted - 17 December 2020; Published online - 19 December 2020en_US
dc.description.abstractThe effect of dietary crude protein (CP) level on intake, digestibility, milk production, and nitrogen (N) use efficiency was studied. Twenty-four Holstein-Friesian cows (17 multiparous and seven primiparous) were grouped by parity, days in milk, milk yield, and live weight into six blocks of four, and randomly assigned to four total mixed ration (TMR) treatments, containing 141, 151, 177, or 210 g CP/kg dry matter (DM), over 28 day experimental periods. Apparent total-tract DM and fiber digestibilities and milk fat composition were similar across treatments. Milk protein and urea-N compositions, and urinary and manure N excretion increased linearly, while milk N efficiency (MNE) decreased linearly with increasing CP. DM intake was highest with the 177 diet, while CP intake increased linearly with increasing CP, peaking at 200 g/kg DM. Milk yield increased with CP intake for the three lower CP levels, peaking at 176 g CP/kg DM. The further increase in CP level from 177 to 210 g/kg DM did not result in improved milk yield, but resulted in decreased milk N secretion and increased urinary N excretion. In summary, milk protein composition increased linearly with increasing CP, accompanied by a linear decrease in MNE, resulting in a bell-shaped relationship between milk yield and dietary CP level.en_US
dc.description.sponsorshipThis research project was funded by the Department of Agriculture Environment and Rural Affairs (DAERA) in Northern Ireland.en_US
dc.identifierhttp://hdl.handle.net/20.500.12518/204
dc.identifier.citationKatongole, C.B. and Yan, T. (2020) ‘Effect of Varying Dietary Crude Protein Level on Feed Intake, Nutrient Digestibility, Milk Production, and Nitrogen Use Efficiency by Lactating Holstein-Friesian Cows’, Animals. MDPI AG. doi:10.3390/ani10122439en_US
dc.identifier.urihttps://doi.org/10.3390/ani10122439
dc.language.isoenen_US
dc.publisherMDPIen_US
dc.rights© 2020 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).en_US
dc.subjectdietary crude proteinen_US
dc.subjectmilk yielden_US
dc.subjectmilk N efficiencyen_US
dc.subjecttotal mixed rationen_US
dc.titleEffect of Varying Dietary Crude Protein Level on Feed Intake, Nutrient Digestibility, Milk Production, and Nitrogen Use Efficiency by Lactating Holstein-Friesian Cowsen_US
dc.typeArticleen_US
dcterms.dateAccepted2020-12-17
dcterms.dateSubmitted2020-11-12

Files

Original bundle
Now showing 1 - 1 of 1
Thumbnail Image
Name:
Effect of varying dietary crude protein level on feed intake, nutrient digestibility, milk production, and nitrogen use efficiency by lactating Holstein-Friesian cows..pdf
Size:
655.45 KB
Format:
Adobe Portable Document Format
Description:
Final published version
Download

Collections

Journal Articles