Twelve heifers were assigned to either a control diet (CON) with 26 g fat per kg dry matter (DM) or a supplemented diet (FAT) with crushed rapeseed with 53 g fat per kg DM. Methane (CH4) emission was measured by open-circuit indirect calorimetry for four days when the heifers weighed approximately 300 kg. Dry matter intake (DMI; P=0.01) and daily CH4 emission (P=0.002) were lowest on the FAT. However, CH4 emission per kg DMI (P=0.21) or per kg weight gain (P=0.44) was not different. The loss of CH4 as a percentage of gross energy intake tended to be lower on FAT (6.4%) than on CON (6.8%; P=0.08). It is concluded that the FAT may have potential to reduce CH4 emission from heifers, but further studies are warranted to document this effect.
Acta Agriculturae Scandinavica. Section A. Animal Science, 2013, Vol 62, Issue 4, 2012, p. 259-262