Changes during ensilage in the nitrogenous components of fresh and additive treated ryegrass and lucerne

Abstract

The changes in the major nitrogenous components of herbage during the ensilage of lucerne and Italian ryegrass, with and without the addition of 85 % formic acid and 40% formaldehyde at the rates of 3.2 and 7.4 g kg-l fresh herbage respectively, were studied. Both herbages were of similar amino-N composition except for asparagine which was about 10% of total nitrogen (TN) in lucerne and only 0.2% of TN in Italian ryegrass. After 90 days ensiling about 90% of the sum of protein-, peptide-, amino-and amide-N was preserved in the additive-treated silages while only 58% was recovered in the untreated lucerne (butyrate) silage. Recoveries of these compounds in the untreated ryegrass (lactate) silage was 83 %. In the butyrate silage, the branched chain amino acids, valine, leucine and isoleucine were well preserved. In addition to these, proline, phenylalanine, glycine, methionine and threonine were well preserved in the lactate silages. Both the untreated silages contained more alanine than in their original respective herbages. Most of the losses from the amine-forming amino acids were recovered as their corresponding amines. Alpha-amino butyric acid and &amino valeric acid were found in both the untreated silages and the quantity present was dependent on the silage quality. In both the additive-treated silages, recoveries of amino acids, other than sulphur amino acids, lysine, histidine, tyrosine and tryptophan, were ca 90% or greater. The losses of these amino acids, excluding the sulphur amino acids, can be attributed mainly to the direct effects of formaldehyde in preventing their estimation following freeze drying or acid hydrolysis.

The Significance of Silage Protein Degradation and Plasma Amino Acid Ratios in the Control of Food Intake by Lambs Fed Ensiled and Fresh Alfalfa

“…in studies quoted above, these amino acids showed a net de-crease in silage. A pattern observed here and also documented by other workers (Ohshima et al 1979;Merchen and Satter 1983) (Gill and Ulyatt 1977) or where casein was infused postruminally in lambs (Egan 1965;Papas et al 1974) food intake was stimulated. Egan and Rogers (1978) have also reported reduction in food intake by lambs experiencing a postruminal imbalance of amino acids.…”

Effects of wilting and mechanical conditioning on proteolysis in sainfoin (Onobrychis viciifolia Scop) wilted herbage and silage

“…13 Bacterial inoculants and treatment of silages with chemicals can also limit protein breakdown and the catabolism of amino acids in grass silages. 14,15 Species containing tannin, such as sainfoin or sulla (Hedysarum coronarium L), undergo less protein degradation during ensiling than species that do not contain tannin. 8 These compounds react with proteins making them resistant to breakdown by proteases both in the silo and in the rumen.…”

<b>Nutritional value of sorghum silages

“…The percentage of crude protein is not modified with the ensiling process, although different proportions of nitrogen fractions may be altered. It is known that fermentation causes changes in the composition of nitrogen fractions, reducing the true protein content and increasing the content of free amino acid, or products from the breakdown of these of amino acids, including ammonia, CO 2 and amines (Ohshima & McDonald, 1979). Thus, the low nitrogen content of silages is a limiting factor for the use of forage of these genotypes mainly for animals with high nutritional requirements.…”