Effect of replacing dietary corn with beet pulp on energy partitioning, substrate oxidation and methane production in lactating dairy goats

Abstract

The objective of this experiment was to study the effect of substitution of corn by beet pulp on energy partitioning, substrate oxidation, nitrogen and carbon balance and milk performance in dairy goats during late lactation. Twelve multiparous lactating Murciano-Granadina goats were fed two diets. Six goats were fed a mixed ration with 310 g/kg DM of ground corn (diet CORN) and in the other diet the corn was substituted with 302 g/kg DM of beet pulp (diet BP) in a cross-over design. No significant differences between diets were observed for milk production (1.36 kg/day, on average) and differences were found for milk fat (5.39 and 4.21% for BP and CORN, respectively). The metabolisable energy intake was higher (P < 0.05) in the CORN diet than BP (1320 vs 1044 kJ/kg0.75 BW, respectively). The difference in methane emissions between treatments was significant (P < 0.05) with values of 92 vs 61 kJ/kg0.75 BW for BP and CORN, respectively, indicating that greater levels of starch in diet reduce methane production. Replacing corn with BP reduced significantly the energy body fat deposition (300 vs 44 kJ/kg0.75 BW for CORN and BP diets, respectively). This reduction in energy retention for the BP diet did not compromise milk yield and milk energy output.

Climate Change and Goat Production: Enteric Methane Emission and Its Mitigation

“…It is well known that increasing the ratio of concentrate to forage in the diet can reduce the amount of energy loss as enteric CH 4 and this is mainly due to change of fermented substrate from fibre to starch [48]. In an experiment conducted on Murciano-Granadina goats in late lactation, Ibáñez et al [50] observed a lower CH 4 production in goats fed with concentrate (ground corn) diet than beet pulp fed goats. However, concentrate feeding beyond a certain limit is not appreciable as it can cause severe damage to the animal itself and to its production performance.…”

Ruminal volatile fatty acid concentration and methane gas production in sheep (Ovis aries) fed two types of basal diets with of without Gliricidia sepium legume forage supplementation

“…Then the mixed solution was distilled by steam and 150-200mL of distillate was collected in an Erlenmeyer flask. The distillate was then titrated with 0.1mol L -1 sodium hydroxide solution to measure the concentration of total VFA (Kromann et al 1967, Ibáñez et al 2014.…”