A novel ammoniation treatment of barley as a strategy to optimize rumen pH, feed degradability and microbial protein synthesis in sheep

Belanche, A., Martín-García, A. I., Jiménez, E., Jonsson, N. N. and Yañez-Ruiz, D. R. (2021) A novel ammoniation treatment of barley as a strategy to optimize rumen pH, feed degradability and microbial protein synthesis in sheep. Journal of the Science of Food and Agriculture, 101(13), pp. 5541-5549. (doi: 10.1002/jsfa.11205) (PMID:33709464) (PMCID:PMC8451892)

Abstract

Background: Meeting the energy and nitrogen requirements of high‐performing ruminants while avoiding digestive disturbances (i.e. rumen acidosis) is a key priority in ruminant nutrition. This study evaluated the effect of a cereal ammoniation treatment, in which barley grains are combined with urea and enzymes that catalyze the conversion of urea to ammonia to optimize rumen function. Twelve rumen cannulated sheep were randomly divided in two groups and fed a diet containing 60% of ammoniated barley (AMM), or untreated barley supplemented with urea (CTL) to study the impact on rumen fermentation and feed utilization. Results: Ammoniated barley had higher total N content and effective rumen degradable N than untreated barely. AMM sheep had a consistently higher rumen pH throughout the day (6.31 vs 6.03) and tended to have a lower post‐prandial ammonia peak and higher acetate molar proportion (+5.1%) than CTL sheep. The rumen environment in AMM sheep favored the colonization and utilization of agro‐industrial by‐products (i.e. orange pulp) by the rumen microbes leading to a higher feed degradability. AMM sheep also had higher total tract apparent N digestibility (+21.7%) and urinary excretion of purine derivatives (+34%) suggesting higher N uptake and microbial protein synthesis than CTL sheep. Conclusions: The inclusion of ammoniated barley in ruminants’ diet represents a valid strategy to maintain rumen pH within a physiological range and to improve N utilization by the rumen microbes which could have positive effects on animal's health and productivity in intensive production systems. These findings warrant further studies under conventional farm conditions.

• Item Type: Articles
• Additional Information: This work was supported by the European Union´s Horizon 2020 research and innovation program under grant agreement No 818368 (MASTER) and Harbro Ltd.
• Status: Published
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Jonsson, Professor Nicholas
• Authors: Belanche, A., Martín-García, A. I., Jiménez, E., Jonsson, N. N., and Yañez-Ruiz, D. R.
• College/School: College of Medical Veterinary and Life Sciences > School of Biodiversity, One Health & Veterinary Medicine
• Journal Name: Journal of the Science of Food and Agriculture
• Publisher: Wiley
• ISSN: 0022-5142
• ISSN (Online): 1097-0010
• Published Online: 11 March 2021
• Copyright Holders: Copyright © 2021 The Authors
• First Published: First published in Journal of the Science of Food and Agriculture 101(13): 5541-5549
• Publisher Policy: Reproduced under a Creative Commons license