The Knowledge Bank is scheduled for regular maintenance on Thursday, August 13th through Friday, August 14th. During this time, users will not be able to register, login, or submit content.
Use of ash and nitrogen concentrations in manure to estimate loss of ammonia over time
|dc.contributor.advisor||Weiss, William P.|
|dc.creator||Paz, Henry A.|
|dc.description.abstract||The aim of this study was to validate a mass balance method based on N and ash in manure to estimate NH3-N losses. Six multiparous Holstein cows were used in a replicated 3 x 3 Latin square. Three diets, corn silage (CS), alfalfa silage (AS) and corn silage + urea (CSU) with different N:Ash ratios, 0.41, 0.37, 0.47 respectively, were fed. During total manure collection, urine and feces samples were used to prepare a slurry (1200 g) in the same proportion as excreted by each cow. Slurries were incubated for 3 d. Initial and final N concentrations and slurry masses were used to determine N losses. Nitrogen loss was estimated as: (N Intake – N Milk) – [N/Ash*(Ash Intake – Ash Milk)]. Average manure output was 65.4 kg/d with cows fed AS and CSU excreting 18.6 kg/d of urine followed by CS at 14.5 kg/d (P= 0.02). Manure N excretion was highest for cows fed CSU followed by AS and CS (422, 392 and 343 g/d, P<0.01). Ash excretion in manure was highest (P<0.01) for cows fed AS (1134 g/d) followed by CS and CSU (936 g/d). Measured NH3-N loss was 30, 41, and 70 g/3 d for AS, CS and CSU and calculated losses were 17, 31, and 75 g/3 d, respectively. Average estimated NH3-N losses did not differ from measured losses (P= 0.15); however, method underestimated NH3-N losses in cows with negative N balance and overestimated it for cows in positive N balance.||en|
|dc.relation.ispartofseries||Animal Sciences. Graduate student poster competition, 2009||en|
|dc.title||Use of ash and nitrogen concentrations in manure to estimate loss of ammonia over time||en|
|dc.rights.cc||Attribution-NoDerivs 3.0 Unported||en_US|
Files in this item
Items in Knowledge Bank are protected by copyright, with all rights reserved, unless otherwise indicated.