Methane emissions from yak (Bos grunniens) steers grazing or kept indoors and fed diets with varying forage concentrate ratio during the cold season on the Qinghai-Tibetan Plateau

NWIPB OpenIR

	Methane emissions from yak (Bos grunniens) steers grazing or kept indoors and fed diets with varying forage concentrate ratio during the cold season on the Qinghai-Tibetan Plateau
	Ding, X. Z. ; Long, R. J. ; Kreuzer, M. ; Mi, J. D. ; Yang, B.
	2010-12-22
发表期刊	ANIMAL FEED SCIENCE AND TECHNOLOGY ; Ding, XZ; Long, RJ; Kreuzer, M; Mi, JD; Yang, B.Methane emissions from yak (Bos grunniens) steers grazing or kept indoors and fed diets with varying forage concentrate ratio during the cold season on the Qinghai-Tibetan Plateau,ANIMAL FEED SCIENCE AND TECHNOLOGY,2010,162(3-4):91-98
摘要	For national greenhouse gas inventories exact data on all major domesticated livestock systems are required Such data is completely lacking for yak (Bos grunniens) and as this ruminant livestock species seems to have digestion and metabolism which differs from cattle making data extrapolations from cattle are potentially inaccurate In the present study methane (CH(4)) emissions from yak were estimated under grazing and indoor feeding conditions in the cold season on the Qinghai-Tibetan Plateau at >3200m above sea level Twelve 3 year old growing yak steers (175 +/- 10 7 kg) were subjected to measurements of CH(4) output using the sulfur hexafluoride tracer gas technique nutrient intake and apparent digestibilities The first group of three yaks grazed on native winter alpine meadows while the indoor groups were fed either oat hay or total mixed diets of oat hay and concentrate in ratios of 0 6 04 and 04 06 respectively on a dry matter (DM) basis The experimental period lasted for 6 weeks with the first 5 weeks for adaptation and the last for measurement The oat hay contained slightly more crude protein (CP) and less fiber compared to the winter pasture grass while inclusion of concentrate increased the CP intake of the yaks considerably Yaks fed indoors gained body weight (BW) during the experimental period (about 200 g/day and slightly higher with concentrate) while grazing yaks lost 550 g/day of BW Daily CH(4) emissions of the grazing yaks were 81 4 g/day or 1 68 g/kg BW(0 75) at an estimated daily grass DM intake of 3 78 kg Absolute levels of CH(4) emissions were slightly higher in the oat hay fed yaks Compared to the oat hay treatment CH(4) production declined by 03 and 04 with forage concentrate ratios of 6 04 and 04 06 respectively Overall the average proportion of gross energy lost as CH(4) energy (kJ/MJ) was 54 +/- 15 2 These values are the CH(4) emission factors (according to Tier 1 of IPCC 2006) of about 28 kg/year for grazing non-lactating yaks weighing 175 kg When adjusted to metabolic BW yaks were at the lower range of CH(4) emission compared to cattle while they were average when CH(4) was related to DM and gross energy intake Implementing proper grazing management practices to improve winter diet quality and quantity and thus animal productivity can be expected to substantially mitigate CH(4) emissions per unit of meat and milk produced by yak (C) 2010 Elsevier BV All rights reserved; For national greenhouse gas inventories exact data on all major domesticated livestock systems are required Such data is completely lacking for yak (Bos grunniens) and as this ruminant livestock species seems to have digestion and metabolism which differs from cattle making data extrapolations from cattle are potentially inaccurate In the present study methane (CH(4)) emissions from yak were estimated under grazing and indoor feeding conditions in the cold season on the Qinghai-Tibetan Plateau at >3200m above sea level Twelve 3 year old growing yak steers (175 +/- 10 7 kg) were subjected to measurements of CH(4) output using the sulfur hexafluoride tracer gas technique nutrient intake and apparent digestibilities The first group of three yaks grazed on native winter alpine meadows while the indoor groups were fed either oat hay or total mixed diets of oat hay and concentrate in ratios of 0 6 04 and 04 06 respectively on a dry matter (DM) basis The experimental period lasted for 6 weeks with the first 5 weeks for adaptation and the last for measurement The oat hay contained slightly more crude protein (CP) and less fiber compared to the winter pasture grass while inclusion of concentrate increased the CP intake of the yaks considerably Yaks fed indoors gained body weight (BW) during the experimental period (about 200 g/day and slightly higher with concentrate) while grazing yaks lost 550 g/day of BW Daily CH(4) emissions of the grazing yaks were 81 4 g/day or 1 68 g/kg BW(0 75) at an estimated daily grass DM intake of 3 78 kg Absolute levels of CH(4) emissions were slightly higher in the oat hay fed yaks Compared to the oat hay treatment CH(4) production declined by 03 and 04 with forage concentrate ratios of 6 04 and 04 06 respectively Overall the average proportion of gross energy lost as CH(4) energy (kJ/MJ) was 54 +/- 15 2 These values are the CH(4) emission factors (according to Tier 1 of IPCC 2006) of about 28 kg/year for grazing non-lactating yaks weighing 175 kg When adjusted to metabolic BW yaks were at the lower range of CH(4) emission compared to cattle while they were average when CH(4) was related to DM and gross energy intake Implementing proper grazing management practices to improve winter diet quality and quantity and thus animal productivity can be expected to substantially mitigate CH(4) emissions per unit of meat and milk produced by yak (C) 2010 Elsevier BV All rights reserved
文献类型	期刊论文
条目标识符	http://210.75.249.4/handle/363003/56107
专题	中国科学院西北高原生物研究所
推荐引用方式 GB/T 7714	Ding, X. Z.,Long, R. J.,Kreuzer, M.,et al. Methane emissions from yak (Bos grunniens) steers grazing or kept indoors and fed diets with varying forage concentrate ratio during the cold season on the Qinghai-Tibetan Plateau[J]. ANIMAL FEED SCIENCE AND TECHNOLOGY, Ding, XZ; Long, RJ; Kreuzer, M; Mi, JD; Yang, B.Methane emissions from yak (Bos grunniens) steers grazing or kept indoors and fed diets with varying forage concentrate ratio during the cold season on the Qinghai-Tibetan Plateau,ANIMAL FEED SCIENCE AND TECHNOLOGY,2010,162(3-4):91-98,2010.
APA	Ding, X. Z.,Long, R. J.,Kreuzer, M.,Mi, J. D.,&Yang, B..(2010).Methane emissions from yak (Bos grunniens) steers grazing or kept indoors and fed diets with varying forage concentrate ratio during the cold season on the Qinghai-Tibetan Plateau.ANIMAL FEED SCIENCE AND TECHNOLOGY.
MLA	Ding, X. Z.,et al."Methane emissions from yak (Bos grunniens) steers grazing or kept indoors and fed diets with varying forage concentrate ratio during the cold season on the Qinghai-Tibetan Plateau".ANIMAL FEED SCIENCE AND TECHNOLOGY (2010).