Nutritional composition and in vitro digestibility of grass and legume winter (cover) crops

Abstract

In dairy farming systems, growing winter crops for forage is frequently limited to annual grasses grown in monoculture. The objectives of this study were to determine how cropping grasses alone or in mixtures with legumes affects the yield, nutritional composition, and in vitro digestibility of fresh and ensiled winter crops and the yield, nutritional composition, and in vitro digestibility of the subsequent summer crops. Experimental plots were planted with 15 different winter crops at 3 locations in Virginia. At each site, 4 plots of each treatment were planted in a randomized complete block design. The 15 treatments included 5 winter annual grasses [barley (BA), ryegrass (RG), rye (RY), triticale (TR), and wheat (WT)] in monoculture [i.e., no legumes (NO)] or with 1 of 2 winter annual legumes [crimson clover (CC) and hairy vetch (HV)]. After harvesting the winter crops, corn and forage sorghum were planted within the same plots perpendicular to the winter crop plantings. The nutritional composition and the in vitro digestibility of winter and summer crops were determined for fresh and ensiled samples. Growing grasses in mixtures with CC increased forage dry matter (DM) yield (2.84 Mg/ha), but the yield of mixtures with HV (2.47 Mg/ha) was similar to that of grasses grown in monoculture (2.40 Mg/ha). Growing grasses in mixtures with legumes increased the crude protein concentration of the fresh forage from 13.0% to 15.5% for CC and to 17.3% for HV. For neutral detergent fiber (NDF) concentrations, the interaction between grasses and legumes was significant for both fresh and ensiled forages. Growing BA, RY, and TR in mixtures with legumes decreased NDF concentrations, whereas growing RG and WT with legumes did not affect the NDF concentrations of either the fresh or the ensiled forages. Growing grasses in mixtures with legumes decreased the concentration of sugars of fresh forages relative to grasses grown in monoculture. Primarily, this decrease can be attributed to low concentrations of sugars of mixtures with HV (10.5%). Growing grasses in mixtures with legumes reduced the fiber digestibility of both winter crops (75.7% to 72.8% NDF). Growing grasses in mixtures with legumes did not affect estimated DM yield, nutritional composition, or digestibility of the succeeding summer crops. In conclusion, growing grasses in mixtures with legumes as winter forage crops can increase forage estimated DM yields and its nutritional quality in dairy farming sytems.

Performance and milk quality of cows fed triticale silage or intercropped with oats or legumes

“…The ash concentration in the legume silages was higher in relation to the triticale silage in monoculture, probably due to the expressive mineral participation of these legumes. Similar results have been described by Brown et al (2018). However, Przemysław et al (2015) evaluated intercropping with alfalfa as the legume crop and reported divergent results.…”

“…There was no difference in dry matter content in the silages (Table 1). Although values were considered low for adequate fermentation (McDonald et al, 1991), the presence of legumes did not reduce these values, as was the case of those observed in other studies (Brown et al, 2018). Crude protein contents differed between silages, recording 13.06 % for TSOPV, 11.63 % for TSP and 7.75 % for ST; this can be attributed to the greater inclusion of legumes in the respective mixtures ( Figure 2).…”

Substituting corn silage with reconstituted forage or nonforage fiber sources in the starter diets of Holstein calves: effects on performance, ruminal fermentation, and blood metabolites

“…Furthermore, due to higher ratio of lignin to fiber in legumes vs. grasses (Kuoppala et al, Table 2. Nutrient intake of Holstein dairy calves as influenced by feeding corn silage or reconstituted alfalfa hay and beet pulp 2009), the lower NDF digestibility in RAH vs. CS would be related to a greater lignin to fiber ratio (Brown et al, 2018). The amounts of digested nutrients were similar across treatment groups, which was substantiated by similar rumen fluid pH and total VFA concentration and profile (Table 4).…”

Replacing alfalfa hay with triticale hay has minimal effects on lactation performance and nitrogen utilization of dairy cows in a semi-arid region of Mexico

“…Under the climate conditions of central Wisconsin, Coblentz et al (2018) suggested that boot stage may be more desirable than soft dough stage at harvest for lactating cows because of nutritional characteristics (particularly as a forage protein source) and harvest management decisions related to seasonal weather conditions for fall planting and spring harvest. Yields and nutritional quality of forage systems may also be altered by growing triticale (and other grasses) in mixtures with legumes as winter crops (Brown et al, 2018). Thus, for intensive dairy farms in the arid and semi-arid environments of Mexico, including triticale in the cropping system at the expense of alfalfa or as a winter crop harvested at boot stage of growth may enhance homegrown forage production, reduce environmental impacts, and facilitate manure nutrient management (Santana, 2018).…”