Protein and free amino acid patterns in maize ensiled with or without urea

Publisher Website
Google Scholar
Abstract
Free and protein amino acid contents of whole‐plant maize ensiled with or without urea were determined at intervals during the fermentation process. The free amino acid content of both untreated and urea‐treated silage increased with time in storage, but the increases were generally larger in the treated silage. The true protein of untreated silage decreased with time in storage. In urea‐treated silage many individual amino acids increased considerably. Among those were the essential amino acids isoleucine, lysine, threonine and valine. The result was a net gain of several amino acids in the treated silage while there was a general decline of most amino acids in the untreated silage. Urea‐treated silage at day 20 contained 38% more true protein and 150% more free amino acids than did untreated silage. The implications of these changes for dairy cattle nutrition are discussed.