Methane emissions from lambs fed kikuyu hay alone or mixtured with lotus hay

Abstract

Dietary inclusion of contain-tannin legumes may reduce enteric methane emission in ruminants. To evaluate methane emissions from sheep fed a kikuyu grass (Cenchrus clandestinus) diet partially substituted with lotus (Lotus uliginosus), twelve growing rams, with 23±2 kg average liveweight, were assigned randomly to two treatments and with three measurement periods in a switchover design. Treatments consisted of 100% kikuyu hay or 70% kikuyu hay: 30% lotus hay and with 6 rams per treatment. Each of three periods lasted 20 d, where the first 15 d were for acclimatization and the last 5 d for measurements. Rams were placed in metabolic cages and fed once a day (8 AM) at 90% of their voluntary feed intake, with free access to drinking water. Feed intake, fecal production and feed digestibility were determined at each period. Methane production was measured for each treatment group of 6 rams using the poly-tunnel technique. Legume addition reduced total methane production (27.6 vs. 23.1 g/animal; p<0.01), methane production per dry matter intake (DMI) (18.8 vs. 12.2 g/kg DMI; p<0.01), methane production per digestible OM (DOM) (36.1 vs. 23.4 g/kg DOM; p<0.01) and methane production per digestible NDF (DNDF) (43.5 vs 34.0 g/kg DNDF; p<0.01). In conclusion, lotus inclusion in pasture systems could be a suitable legume to reduce methane emissions in grazing systems.