Methane emissions from beef cattle: Effects of monensin, sunflower oil, enzymes, yeast, and fumaric acid1

Abstract

Methane emitted from the livestock sector contributes to greenhouse gas (GHG) emissions. Understanding the effects of diet on enteric methane production can help refine GHG emission inventories and identify viable GHG reduction strategies. Our study focused on measuring methane and carbon dioxide emissions, total-tract digestibility, and ruminal fermentation in growing beef cattle fed a diet supplemented with various additives or ingredients. Two experiments, each designed as a 4 x 4 Latin square with 21-d periods, were conducted using 16 Holstein steers (initial BW 311.6 +/- 12.3 kg). In Exp. 1, treatments were control (no additive), monensin (Rumensin, Elanco Animal Health, Indianapolis, IN; 33 mg/kg DM), sunflower oil (400 g/d, approximately 5% of DMI), and proteolytic enzyme (Protex 6-L, Genencor Int., Inc., CA; 1 mL/kg DM). In Exp. 2, treatments were control (no additive), Procreatin-7 yeast (Prince Agri Products, Inc., Quincy, IL; 4 g/d), Levucell SC yeast (Lallemand, Inc., Rexdale, Ontario, Canada; 1 g/d), and fumaric acid (Bartek Ingredients Inc., Stoney Creek, Ontario, Canada; 80 g/d). The basal diet consisted of 75% barley silage, 19% steam-rolled barley grain, and 6% supplement (DM basis). Four large chambers (two animals per chamber) were equipped with lasers and infrared gas analyzers to measure methane and carbon dioxide, respectively, for 3 d each period. Total-tract digestibility was determined using chromic oxide. Approximately 6.5% of the GE consumed was lost in the form of methane emissions from animals fed the control diet. In Exp. 1, sunflower oil decreased methane emissions by 22% (P = 0.001) compared with the control, whereas monensin (P = 0.44) and enzyme had no effect (P = 0.82). However, oil decreased (P = 0.03) the total-tract digestibility of NDF by 20%. When CH(4) emissions were corrected for differences in energy intake, the loss of GE to methane was decreased by 21% (P = 0.002) using oil and by 9% (P = 0.09) using monensin. In Exp. 2, Procreatin-7 yeast (P = 0.72), Levucell SC yeast (P = 0.28), and fumaric acid (P = 0.21) had no effect on methane emissions, although emissions as a percentage of GE intake were 3% (non-significant, P = 0.39) less for steers fed Procreatin-7 yeast compared with the control. This study demonstrates that sunflower oil, ionophores, and possibly some yeast products can be used to decrease the GE lost as methane from cattle, but fiber digestibility is impaired with oil supplementation.

Effect of disodium fumarate on microbial abundance, ruminal fermentation and methane emission in goats under different forage : concentrate ratios

“…With Holstein steers, Bayaru et al (2001) reported that 20 g/kg DM fumaric acid supplementation caused a 23% decrease in methane production and increased propionate concentration, but had no effect on the concentration of ruminal acetate. McGinn et al (2004) fed 12 g/kg DM fumaric acid to cattle and reported no effect on methane production, total VFA concentration and propionate proportions. Difference in responses might be dose or diet related.…”

“…Bayaru et al (2001) observed a 23% decrease in methane production when fumaric acid was added at 20 g/kg dry matter (DM) to a complete forage diet fed to two steers. On the contrary, no effect on methane emissions was reported on steers fed barley silage and concentrate with fumaric acid (12 g/kg DM; McGinn et al, 2004), or on wether lambs fed dried ground lucerne with up to 100 g/kg fumaric acid (Molano et al, 2008). These contradictory results could be due to the differences in the type of diet.…”

Mitigating climate change: the role of domestic livestock

“…Apparently significant successes in decreasing methane production have been achieved in experiments in vitro or in single animal feeding trials (e.g. Lopez et al, 1999;McGinn et al, 2004) but these have not proved to be robust when applied to a variety of feeding regimes and some methods such as the use of ionophores are banned in the European Union. Research is continuing in New Zealand using a variety of approaches co-ordinated through the Pastoral Greenhouse gas Research consortium (PGgRc, 2009).…”

A re-examination of the technical feasibility and economic viability of rapeseed dehulling

“…The oil content may nevertheless be valued by dairy cow or goat farmers Indeed, the introduction of lipids in their rations can result in higher milk production with more proteins and reduced saturated fatty acids (Brunschwig et al, 2006). Methane emissions by ruminants may be reduced by adding unsaturated oils to their feed (McGinn et al, 2004) although reduction by this means can according to Beauchemin, Martin and their colleagues, result the fibre fraction becoming less digestible (Beauchemin et al, 2006) (Martin et al, 2008). In view of the growing concern about greenhouse gases emissions from cattle, these properties could render processed rapeseed hulls an attractive source of forage, especially in intensive large production units where roughage has to be brought in from distant areas.…”