Advanced search
Start date
Betweenand
(Reference retrieved automatically from Web of Science through information on FAPESP grant and its corresponding number as mentioned in the publication by the authors.)

Strategic grazing management decreases nitrogen excretion intensity of dairy cows

Full text
Author(s):
Araujo Batalha, Camila Delveaux [1] ; Souza Congio, Guilhermo Francklin de [1] ; Portela Santos, Flavio Augusto [1] ; da Silva, Sila Carneiro [1]
Total Authors: 4
Affiliation:
[1] Univ Sao Paulo, ESALQ, Dept Zootecnia, CP 09, BR-13418900 Piracicaba, SP - Brazil
Total Affiliations: 1
Document type: Journal article
Source: Scientia Agricola; v. 79, n. 2 2022.
Web of Science Citations: 0
Abstract

ABSTRACT: There is limited information regarding both nitrogen (N) and energy partitioning of dairy cows grazing well–managed tropical pastures. The objective of this study was to investigate the N and energy partitioning of mid–lactation dairy cows on rotationally grazed elephant grass using two pre–grazing targets: 95 % or maximum canopy light interception (LI95% or LIMax) during regrowth. The study used 26 Holstein × Jersey dairy cows arranged in a randomized complete block design with three 40–day periods of sampling. Grazing at LI95% increased organic matter and crude protein intake by 20 % (p ≤ 0.05) which resulted in a 9 % increase in fat corrected milk yield (p ≤ 0.05) relative to LIMax. Cows grazing at LI95% had greater concentration of total volatile fatty acids, butyrate and valerate (p ≤ 0.05), and smaller acetate (p ≤ 0.05) than those grazing at LIMax. Intake of net energy for lactation (NEL) and NEL secreted in milk were greater (p ≤ 0.05), while partitioning of NEL towards maintenance tended to be greater (p = 0.07) for cows grazing at LI95% than those grazing at LIMax. Milk urea nitrogen and both urine and fecal N excretion were greater for cows grazing at LI95% (p ≤ 0.05), but N excretion intensity was lower than in cows grazing at LIMax (p ≤ 0.05). Strategic grazing management using the LI95% pre–grazing target increases N losses through both urine and feces; however, it reduces N excretion intensity of dairy cows by 9 %. (AU)

FAPESP's process: 16/22040-2 - Nutritive value, milk yield and greenhouse gas emissions in elephant grass cv. Cameroon subjected to strategies of rotational grazing by dairy cows
Grantee:Sila Carneiro da Silva
Support Opportunities: Regular Research Grants