Silage Fermentation and In Vitro Degradation Characteristics of Orchardgrass and Alfalfa Intercrop Mixtures as Influenced by Forage Ratios and Nitrogen Fertilizing Levels

Abstract

Intercropping is a globally accepted method of forage production and its effect on silage quality depends not only on forage combination but also fertilization strategy. In the present study, field intercropping of orchardgrass (Dactylis glomerata) and alfalfa (Medicago sativa) at five seed ratios (100:0, 75:25: 50:50, 25:75, 0:100 in %, based on seed weight) was applied under three N fertilizing levels (0, 50, and 100 kg/ha), and harvested for silage making and in vitro rumen degradation. As a result of intercropping, the actual proportions (based on dry matter) of alfalfa in mixtures were much closer to seed proportion of alfalfa in field, except 75:25 orchardgrass-alfalfa intercrops with no fertilization. The actual proportions of alfalfa in mixtures decreased by 3–13% with the increase of N level. Increases of alfalfa proportion in mixtures increased silage quality, nutrients degradability and CH4 emissions. Increasing N levels increased silage pH, concentration of butyric acid, and fiber fractions. In summary, inclusion of alfalfa at around 50% in orchardgrass-alfalfa silage mixtures were selected for favorable ensiling and higher forage use efficiency while also limiting CH4 emissions, compared to monocultures. The silage quality and feeding values of mixtures were influenced more by forage ratios than by N levels.

Condensed tannins extracted from Quebracho affect the fermentation profile, nutritional quality and in vitro gas production of pornunça (Manihot spp.) silages

“…They are readily available for degradation and fermentation is faster, resulting in shorter fermentation time. After the reduction in NFC fermentation, the fermentation of FC is continued, since they are fermented more slowly (Xue et al, 2020). These facts explain the reason for the approximation of the cumulative gas production curve between treatments after 72 h incubation.…”

Intercropping of orchardgrass and alfalfa improves soil fertility, forage yield, feeding values and land use efficiency while limiting ruminal greenhouse gas emissions

“…The soil (0–20 cm) at the site was a sandy loam, including the following properties with pH 7.89, total N 0.76 g kg −1 , phosphorus (P) 14.8 mg kg −1 , and available potassium (K) 79.3 mg kg −1 , and organic matter 12.5 g kg −1 . Further details of the experimental site have been described previously (Xue, Wang, et al, 2020). The monthly total precipitation and mean temperature during the growing seasons (2016 and 2017) is given in Figure S1.…”

“…Experimental design and planting procedures were referred to Xue, Wang, et al (2020). This study employed the typical replacement series design and technique outlined by De Wit (1960).…”

“…The harvested orchardgrass and alfalfa were dried at 65°C for 48 h to compute the total forage DM yield and botanical composition, and sub‐samples were ground to pass through a 1 mm sieve for later chemical analysis. Data for the botanical compositions, CP, and neutral detergent fibre (NDF) in the first and second cut in 2016 have been previously reported (Xue, Wang, et al, 2020), but data for the other measurements, cuts, and production years have not been published.…”

Silage quality traits of sorghum-sudangrass hybrid and sunn hemp mixtures at different ratios in the Mediterranean climate

“…The combination of forage grasses with legumes is one of the effective methods for the preparation of high quality silage (Ridwan et al, 2015). Forage legumes such as soybean, pea, alfalfa or others can be ensiled by mixing up to 50% with forage grass in order to increase the quality, especially crude protein (Zavala et al, 2011;Sulas et al, 2012;Zhang et al, 2015;Budakli Carpici, 2016;Xue et al, 2020). Sunn hemp Ozkan (Crotalaria juncea L.), which is known to contain 30% protein in its leaves, is an annual, fast-growing, multipurpose alternative legume for the warm season, and it is extensively cultivated in subtropical and tropical regions (Chaudhury et al, 1997;Mosjidis et al, 2013;Demiroglu Topcu and Ozkan, 2019a).…”