Methane emissions of stored manure from dairy cows fed conventional or brown midrib corn silage

Abstract

The objective of this study was to examine the effects of feeding conventional corn silage (CCS) or brown midrib corn silage (BMCS) to dairy cows on CH 4 emissions from stored manure. Eight lactating cows were fed (ad libitum) a total mixed ration (forage: concentrate ratio 65:35; dry matter basis) containing 59% (dry matter basis) of either CCS or BMCS. Feces and urine were collected from each cow and mixed with residual sludge obtained from a manure storage structure. Manure was incubated for 17 wk at 20°C under anaerobic conditions (O 2-free N 2) in 500-mL glass bottles. Methane emissions and changes in chemical composition of the manure were monitored during the incubation period. The total amount of feces and urine excreted was higher for cows fed BMCS than for cows fed CCS [8.6 vs. 6.5 kg/d of volatile solids (VS)]. Manure from cows fed BMCS emitted more CH 4 than manure from cows fed CCS (173 vs. 146 L/kg of VS) throughout the incubation period. Similarly, VS and neutral detergent fiber losses throughout incubation were higher for manure from cows fed BMCS versus cows fed CCS (37.6 vs. 30.6% and 46.2 vs. 31.2%, respectively). Manure NH 3 concentration (79% of total manure N) was not affected by corn silage cultivar. Results of this study show that using a more digestible corn silage cultivar (BMCS vs. CCS) may increase the contribution of manure to CH 4 emissions, and may offset gain achieved by reducing enteric CH 4 emissions.

Frequency of diet delivery to dairy cows: Effect on nutrient digestion, rumen fermentation, methane production, nitrogen utilization, and milk production

“…Maximal CH 4 emission potential averaged 148 L/kg of VS and was not affected by frequency of diet delivery, which was consistent with the absence of treatment effect on VS and NDF excreted (Table 10). In this study, the observed values of maximal CH 4 production potential of manure are within the range of values (85 to 197 L/kg of VS) observed in our previous studies (Massé et al, 2016;Benchaar and Hassanat, 2019; Benchaar and Hassanat: FREQUENCY OF DIET DELIVERY TO DAIRY COWS Means within rows with different lowercase superscripts differ (P < 0.05).…”

“…Diet manipulation has been shown to influence CH 4 production in dairy cows (Brask et al, 2013;Benchaar et al, 2015;Hassanat et al, 2017). When dietary interventions affected DMI or ruminal OM fermentation, the amount and the composition of manure volatile solids (VS) were changed, affecting CH 4 emissions from stored manure (Møller et al, 2014;Benchaar and Hassanat, 2019;Hassanat and Benchaar, 2019). However, studies investigating the effect of non-nutritional feeding management practices (e.g., frequency of diet delivery) on CH 4 emissions from enteric fermentation and manure storage are scarce.…”

Enteric and Fecal Methane Emissions from Dairy Cows Fed Grass or Corn Silage Diets Supplemented with Rapeseed Oil

“…Partial replacement of GS by CS resulted in a numerical increase in OM output in the feces. Similarly, Benchaar and Hassanat [ 23 ] found that dairy cows fed midrib corn silage excreted more volatile solids than cows fed conventional corn silage. The OM output in the present study was also numerically higher for the diets supplemented with RSO.…”

Effects of rumen undegradable protein sources on nitrous oxide, methane and ammonia emission from the manure of feedlot-finished cattle

“…The amount of CH 4 emitted from manure is small compared with the total amount of enteric CH 4 produced by ruminants 20 . However, emission from manure in feedlots is relevant, because large volumes of manure can result in higher CH 4 emission 21 .…”