Impact of grass silage quality on greenhouse gas emissions from dairy and beef production

Abstract

High‐quality grass silages may represent a mitigation option by reducing enteric methane production and by increasing productivity, thus reducing greenhouse gas emissions per kg of product (emission intensity). Two previous studies found considerable effects of three different silage qualities cut at different maturity stages (very early [H1], early [H2] and normal [H3]) offered ad libitum with various levels of concentrate supplementation, on animal performances of growing/finishing bulls and dairy cows in early lactation, indicating that emission intensities may also vary. Based on results from these previous studies, the aim of this study was to estimate emission intensities for milk and beef carcasses for the included combinations of silage qualities and concentrate levels, by using the farm‐scale model HolosNor. The emissions intensities were lowest for the H1 silage, and highest for the H3 silage, independent of concentrate levels for both milk and beef. Thus, increasing concentrate levels did not compensate for lower grass silage quality. Improvements in silage quality from H3 silage to H2 is realistic and has the potential to reduce emission intensities with approximately 10% while keeping the milk yield per cow constant and reducing the use of concentrates considerably. For beef production, the potential is even larger, with a reduction in emission intensity of approximately 17%. We conclude that improving grass silage quality may be a mitigation option that will also reduce the dependence on concentrates.

Lactic Acid Bacteria as Microbial Silage Additives: Current Status and Future Outlook

“…They are classified as alcohols, esters, and aldehydes [63,64]. Production and volatilization of these compounds contribute to a reduction in quality of the stored feed, inducing ground-level ozone, and influence emission of greenhouse gases by the agricultural sector [65].…”

“…On a broader geographic area, these differences will be minimized by the inclusion of higher numbers of farms, up to a point that patterns of variations could be analyzed. This type of analysis was performed by Gallo et al in two recent studies [65,66]. The team used a multivariate analysis technique, Principal Component Analysis (PCA), to evaluate ensiling of corn silage on 68 dairy farms [66] and generated a fermentation quality index to rank the silage [67].…”

Effects of Additive Type on Fermentation and Aerobic Stability and Its Interaction with Air Exposure on Silage Nutritive Value

“…Silage from various crops plays an important role in ruminant nutrition in many geographical areas of the world. Variations in silage quality and losses from field to trough largely affect the environmental impact of animal production as well as profitability and sustainability [1][2][3][4]. Therefore, all metabolic pathways facilitated by undesired microorganisms, which lead to significant losses of nutrients and energy during storage, e.g., butyric acid fermentation by clostridia and ethanol production by yeasts [1,5], must be suppressed in order to maintain the highest silage quality until silo opening.…”

Effects of Various Additives on Fermentation, Aerobic Stability and Volatile Organic Compounds in Whole-Crop Rye Silage

“…Agriculture in general and forage production in particular have been put under scrutiny regarding their impact on the environment, including greenhouse gas emissions [24][25][26][27][28]. The review by Hafner et al [29] focused on the range of volatile organic compounds (VOCs) produced in and potentially emitted from silage, their sources and environmental implications.…”