Abstract

This experiment tested the hypothesis that addition of an organic acid (fumarate) would increase the energy captured from a pasture diet during ruminal fermentation. Pasture was fermented with 0, 10, 20, or 30 mM of fumarate constantly infused into four dual-flow continuous culture fermenters. Digestion characteristics responded linearly (P<0.05) as fumarate increased from 0 to 30 mM. Increasing fumarate from 0 to 30 mM reduced (P=0.057) methane production by 38%, and reduced the ratio of acetate:propionate (2.4 v.s. 1.5). Concentrations of propionate and total volatile fatty acids increased by 74% and 19%, respectively. These results were consistent with fumarate acting as an electron-accepting intermediary in the succinate-propionate pathway. The addition of fumarate increased energy capture from a pasture diet by improving the supply of glucogenic compounds and reducing losses to methane emissions.

ES, Kolver, PW Aspin, GN Jarvis, KM Elborough, and JR Roche

Proceedings of the New Zealand Society of Animal Production, Volume 64, Hamilton, 155-159, 2004