Estimation of methane emissions from local and crossbreed beef cattle in Daklak province of Vietnam.
OBJECTIVE
This study was aimed at evaluating effects of cattle breed resources and alternative mixed-feeding practices on meat productivity and emission intensities from household farming systems (HFS) in Daklak Province, Vietnam.


METHODS
Records from Local Yellow×Red Sindhi (Bos indicus; Lai Sind) and 1/2 Limousin, 1/2 Drought Master, and 1/2 Red Angus cattle during the growth (0 to 21 months) and fattening (22 to 25 months) periods were used to better understand variations on meat productivity and enteric methane emissions. Parameters were determined by the ruminant model. Four scenarios were developed: (HFS1) grazing from birth to slaughter on native grasses for approximately 10 h plus 1.5 kg dry matter/d (0.8% live weight [LW]) of a mixture of guinea grass (19%), cassava (43%) powder, cotton (23%) seed, and rice (15%) straw; (HFS2) growth period fed with elephant grass (1% of LW) plus supplementation (1.5% of LW) of rice bran (36%), maize (33%), and cassava (31%) meals; and HFS3 and HFS4 computed elephant grass, but concentrate supplementation reaching 2% and 1% of LW, respectively.


RESULTS
Results show that compared to HFS1, emissions (72.3±0.96 kg CH4/animal/life; least squares means± standard error of the mean) were 15%, 6%, and 23% lower (p<0.01) for the HFS2, HFS3, and HFS4, respectively. The predicted methane efficiencies (CO2eq) per kg of LW at slaughter (4.3±0.15), carcass weight (8.8±0.25 kg) and kg of edible protein (44.1±1.29) were also lower (p<0.05) in the HFS4. In particular, irrespective of the HSF, feed supply and ratio changes had a more positive impact on emission intensities when crossbred 1/2 Red Angus cattle were fed than in their crossbred counterparts.


CONCLUSIONS
Modest improvements on feeding practices and integrated modelling frameworks may offer potential trade-offs to respond to climate change in Vietnam.
CSIRO Agriculture, Australian Tropical Sciences and Innovation Precinct, James Cook University, Townsville, QLD 4811, Australia.
Carlos Alberto
CA
Ramírez-Restrepo
Tay Nguyen University, 567 Le Duan, Buon Ma Thuot City, Vietnam.
Dung
D
Van Tien
Hue University of Agriculture & Forestry, Hue University, 102 Phung Hung, Hue city, Vietnam.
Ngoan
N
Le Duc
CSIRO Agriculture, Australian Tropical Sciences and Innovation Precinct, James Cook University, Townsville, QLD 4811, Australia.
Mario
M
Herrero
Hue University of Agriculture & Forestry, Hue University, 102 Phung Hung, Hue city, Vietnam.
Phung
P
Le Dinh
Hue University of Agriculture & Forestry, Hue University, 102 Phung Hung, Hue city, Vietnam.
Dung Dinh
DD
Van
Hue University of Agriculture & Forestry, Hue University, 102 Phung Hung, Hue city, Vietnam.
Sen
S
Le Thi Hoa
National Institute of Animal Sciences, Thuy Phuong, Tu Liem, Hanoi, Vietnam.
Cuong Vu
CV
Chi
Universidad Técnica Nacional, Atenas Campus, Alajuela 20501, Costa Rica.
Cesar
C
Solano-Patiño
Woodrow Wilson School of Public and International Affairs Science, Technology, and Environmental Policy Princeton University, Princeton, NJ 08544, USA.
Amy M
AM
Lerner
Woodrow Wilson School of Public and International Affairs Science, Technology, and Environmental Policy Princeton University, Princeton, NJ 08544, USA.
Timothy D
TD
Searchinger
Household Farming; Methane Emissions; Modelling; Ruminant