Effects of inoculants and wilting on silage fermentation and nutritive characteristics of red clover–grass mixtures

Abstract

Various management practices (e.g. wilting, application of silage additives or adding a grass component) can be used to improve silage fermentation of pure red clover (Trifolium pratense L.). Therefore, the aim of this laboratory ensiling study was to investigate the effects of varying proportions of red clover and perennial ryegrass (100/0, 66/33, 33/66, 0/100) on silage quality during two consecutive years. In addition, two wilting levels [target dry matter (DM): 300 vs. 400 g kg−1] in combination with lactic acid bacteria (LAB) additives were tested. Herbage was ensiled, either untreated or inoculated with homofermentative LAB (low wilted) or homo‐ and heterofermentative LAB (high wilted). In most cases, lactic and acetic acid decreased as the proportions of ryegrass were increased. Data concerning ammonia‐N concentrations showed considerable differences between cuts and years. Silages treated with homofermentative LAB generally had high lactic acid and low final pH, whereas acetic acid and 1,2‐propanediol tended to be higher when homo‐ and heterofermentative LAB were applied. Inoculants had a positive effect on DM losses and ammonia‐N in only a few silages. Wilting decreased DM losses and fermentation acids at most cuts, irrespective of the grass/clover ratio in the herbage mixture. There was a strong year effect on the organic matter digestibility (DOM) of the silages. In conclusion, the optimal strategy for successful silage fermentation of red clover is the ensiling in mixtures with ryegrass. Furthermore, herbage should be wilted to a DM content of about 300–350 g kg−1. The application of LAB inoculants did not alter the DOM but did improve silage fermentation.

Effect of Lactobacillus plantarum ‘KR107070’ and a propionic acid‐based preservative on the fermentation characteristics, nutritive value and aerobic stability of alfalfa‐corn mixed silage ensiled with four ratios

“…A few studies have demonstrated that formic acid decreased NH 3 -N concentration in silage (Nagel and Broderick 1992;Ding et al 2013;Li et al 2016). The application of LP alone, or in combination with AD, significantly increased LA content in alfalfa-corn mixed silage, which coincides with Krawutschke et al (2013).…”

“…A few studies have demonstrated that formic acid decreased NH 3 -N concentration in silage (Nagel and Broderick 1992;Ding et al 2013;Li et al 2016). The application of LP alone, or in combination with AD, significantly increased LA content in alfalfa-corn mixed silage, which coincides with Krawutschke et al (2013). As can be seen from Table 3, the alfalfa-corn ratio factor had a significant effect on the nutritive value of mixed silage, which agrees with Zhang et al (2015), because the differences on nutrition indexes between alfalfa and corn were obvious (Table 1) and different mixture ratios led to this remarkable influence.…”

“…Ensilability of alfalfa can be enhanced by conventional approaches, such as utilization of fibrolytic enzymes and additives rich in sugar (Sheperd et al 1995;Wu and Nishino 2016), wilting (Krawutschke et al 2013) and use of lactic acid bacteria (LAB) and short-chain organic acids or salts (Nagel and Broderick 1992;Krawutschke et al 2013;Wen et al 2017). Additives such as cellulase and molasses are often costly commercially and impracticable for dairy farms; in addition, application of them sometimes did not have a remarkable effect on the fermentation properties of alfalfa silage (Kozelov et al 2008;Hashemzadeh-Cigari et al 2014;Lyncha et al 2014).…”

“…Alfalfa (Medicago sativa L.) is one leguminous forage difficult to ensile due to its low sugar content and high buffering capacity (Wilson and Webb 1937;Singh et al 1985;Fisher and Burns 1987;Davies et al 1998;Ogunade et al 2016), low dry matter (DM) content (McDonald et al 1991) and extensive proteolysis during fermentation (Ke et al 2015). Ensilability of alfalfa can be enhanced by conventional approaches, such as utilization of fibrolytic enzymes and additives rich in sugar (Sheperd et al 1995;Wu and Nishino 2016), wilting (Krawutschke et al 2013) and use of lactic acid bacteria (LAB) and short-chain (Marsalis et al 2010), owing to its high water soluble carbohydrates (WSC), low buffering capacity and relatively high DM content in spite of the low protein content (usually <100 g kg À1 DM) (McDonald et al 1991). Corn and alfalfa are complementary to each other in chemical properties (Brito and Broderick 2006); furthermore, corngrowing areas are around the alfalfa fields and one cut of alfalfa and whole-plant corn harvest schedules are overlapped in many northern parts of China such as Inner Mongolia.…”

“…The 60% corn silage, treated with combining 0.24% propionic acid, 0.24% sodium propionate and 0.18% formic acid with L. plantarum 'KR107070', is better in terms of conservation quality and aerobic stability. organic acids or salts (Nagel and Broderick 1992;Krawutschke et al 2013;Wen et al 2017). Additives such as cellulase and molasses are often costly commercially and impracticable for dairy farms; in addition, application of them sometimes did not have a remarkable effect on the fermentation properties of alfalfa silage (Kozelov et al 2008;Hashemzadeh-Cigari et al 2014;Lyncha et al 2014).…”