Protein characteristics in grass–clover silages according to wilting rate and fermentation pattern

Abstract

Effects of wilting rate and fermentation stimulators and inhibitors on protein characteristics of forages typical for organic production were assessed using traditional analytical methods and a gas production in vitro assay. The hypotheses were that the proportion of the crude protein (CP) fraction that was soluble would be lowest, and the protein feed value highest, under rapid wilting and restricted fermentation. The solubility of the CP fraction varied according to treatments and between a first and a second cut, with moderate and high content of clover respectively. It was, however, of minor importance for the protein value, both calculated as amino acids absorbed in the small intestine (AAT20) and estimated as effective utilizable crude protein (uCP04) by the in vitro assay. In ensiled herbage, AAT20 was highest in rapidly wilted and restrictedly fermented silages made from a first cut dominated by highly digestible grasses. Silages from the second cut dominated by red clover were far lower in AAT20. The in vitro assay did not separate silages according to herbage composition or wilting rate, but ranked restrictedly fermented above extensively fermented with regard to protein supply. The assay might still have caught the characteristics that determine the true protein value in vivo.

Estimation of Nutritive Value and Protein Degradability of Trifolium Repens and Poa Pratensis as the Dominant Pasture Species, Under Simulated Rotational Grazing

“…Tas et al (2006) also found that the concentration of CP in perennial ryegrass forage was the highest for the first harvest compared with later summer harvests. According to Bakken et al (2016), the grass-clover herbage from the first cut was higher than the second cut in concentrations of water-soluble carbohydrates. The current research confirmed the negative relationship between the fiber (NDF and ADF) and nonfiber carbohydrate concentrations in the grass and legume forages, earlier determined by Zhao et al (2008).…”

“…Pelletier et al (2010) found that DM digestibility was lower in the summer regrowth than the spring growth of grass and legume forage, and this decrease was more prominent in forage grasses than in legumes (up to 19 and 7%, respectively). According to Bakken et al (2016), the concentration of net energy lactation was higher in the first than in the second cut of grass-clover sward, whereas Steg et al (1994) reported that clover had a higher content of rumen degradable OM than grass. Dry matter degradability of grass-legume pasture tended to decrease from the first to the second harvest, due to the changes in the cell walls to cell contents ratio (Keim et al, 2013).…”

In Vitro Rumen Fermentation Characteristics, Estimated Utilizable Crude Protein and Metabolizable Energy Values of Grass Silages, Concentrate Feeds and Their Mixtures

“…Similarly, heat treatment of protein ingredients increases the duodenal flow of amino acids [11,12]. On the other hand, the use of silage additives [13], the degree of wilting at ensiling [14], and most commonly, modulation of the stage of crop maturity at cutting [15] are some of the management tools to alter the nutritive value of grass silages. Here, we assessed the in vitro rumen fermentation kinetics, estimated the metabolizable energy (ME) and utilizable crude protein (uCP) values of different formulations of concentrate feeds, contrasting qualities of grass silages, and mixtures of the concentrate feeds and grass silages (assuming a hypothetical dairy cow ration) using the ANKOM RF wireless gas production system (ANKOM Technology, Macedon, NY, USA).…”

Effect of grassland cutting frequency, species mixture, wilting and fermentation pattern of grass silages on in vitro methane yield

“…Elevated DM concentration and reduced fermentation intensity in silage retain more WSC in the silage 22,23 . In addition, the use of formic acid-based additives that restrict fermentation can potentially preserve silage concentrations of WSC compared to silages prepared without additives or with the use of lactic acid bacteria inoculants 24,25 .…”