International Perspective: Methane Research · Haisan et al. (2014) Dairy 60 Reynolds et al. (2014)...
Transcript of International Perspective: Methane Research · Haisan et al. (2014) Dairy 60 Reynolds et al. (2014)...
Lethbridge Research Centre, Lethbridge, Alberta, Canada
International Perspective: Methane Research
Tim McAllister
Gerber et al. 2012
Mtonne CO2e
Total emissions from the global livestock industry
0
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1000
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3000
Beef Cattle Dairy Cattle Pigs Buffalo Poultry SmallRuminants
Enteric CH4 – 39% of total
livestock emissions
Strategies to Lower C-Footprint of Cattle
1) Technology to reduce emissions • Lowering enteric methane
2) Intensification/efficiency
• Increasing milk and meat production (i.e., more food per unit of GHG produced)
Total GHG emissions (CO2 eq)
Unit of product produced
Canada
• CH4 mitigation, N03-,
3NOP, probiotics
• CH4 emissions - feed
efficiency
• CH4 emissions from ILO
• CH4 emission from
manure storage
• Modeling, Holos
• AAFC, Lethbridge; U of
A; U of Guelph; U of M
Canada
United
States
• CH4 mitigation, N03-,
3NOP, essential oils
• CH4 emission from ILO
• Modeling,
• USDA/ARS, Penn State;
Ohio State, UC Davis;
United States
SOUTH
AMERICA
• CH4 - Inventory estimates
• CH4 – relates to feed
energetics
• Embrapa, INTA, INIA
Brazil, Uruguay,
Argentina, Chile
Columbia
EUROPE
• Animal Change
• Ruminomics
• 3-NOP
• Forage breeding
• INRA; Rowett;
Wageningen; Teagasc
Europe
ASIA
• CH4 - Inventory
• Yak
• CH4 - biogas
China, Malaysia,
Vietnam, Indonesia
AUSTRALIA
• CH4 – emissions on
pasture
• CH4 – measurement
methodology
• Low CH4 emitting
genetics
• NO3- blocks
• CH4 – Microbiology
• DPI, CSIRO, U of
Queensland, U of N
England, U of W
Australia
Australia
New Zealand
• CH4 – Vaccine,
chemical inhibitors
• Low CH4 forages
• Low CH4 genetics
• Rumen microbiology
• Global Rumen census
• Hungate 1000
• NZAGRC-PGgRC
New Zealand
Strategies to Reduce Methane Emissions
Diet
Rumen
microbiome and
fermentation
Animal
genetics
photo by Julia Palmer
Methane mitigation effect Long-term mitigation effect Safety
Inhibitors
3-nitrooxypropanol Medium ? ?
Electron receptors
Nitroethane Low No No
Nitrate High No? Yes?
Ionophores Low No? Yes?
Plant bioactive compounds
Tannins (condensed) Low No? Yes?
Saponins Low? No No?
Essential oils Low? No No
Bacterial direct fed microbials Low? No Yes
Defaunation Low No No
Dietary lipids Medium No? Yes?
Inclusion of concentrate Low to medium Yes Yes?
Improving forage quality Low to medium Yes Yes
Grazing management Low Yes Yes?
Feed processing Low Yes Yes
Mixed rations and feeding frequency ? ? ?
Precision (balanced) feeding and feed analysis Low to medium Yes Yes
(Hristov et al., 2013)
Dietary Strategies to Reduce Methane Emissions
CH4 Inhibitor: 3-Nitrooxypropanol
Synthetic compound (DSM Nutritional
Products, Switzerland)
“Clean cow” additive (2018)
Inhibits the reduction of methyl-
coenzyme M to CH4 by methyl-
coenzyme reductase during the last
step of methanogenesis in the rumen
Low safety risk (not carcinogenic or
mutagenic)
Proposed Mode of Action:
3-NOP binds to the active site of the
Methyl-coenzyme reductase
Study Animal CH4 reduction, % Martinez-Fernandez et al. (2014) Sheep 26
Romero-Perez et al. (2014) Beef 33
Haisan et al. (2014) Dairy 42
Haisan et al. (2014) Dairy 60
Reynolds et al. (2014) Dairy 7
Short term studies evaluating NOP
Mode of supplementation
Directly in the rumen
Top-dressed in the feed
Mixed with the feed
Mixed with the feed
Directly into the rumen
Methane emissions of beef cattle fed a 70% forage
diet top dressed once daily with increasing levels of
3-nitrooxypropanol
Romero-Perez et al. 2014 J. Anim. Sci.
24.62a
23.54a
22.33a
16.48b
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0 0.75 2.25 4.5
CH
4, g
/kg
DM
I
mg NOP/kg BW
33 %
10.75 mg/kg BW = 0.5 g/d; 2.25mg/kg BW = 1.4 g/d; 4.5 mg/kg BW = 2.7 g/d. a,b (P˂0.001).
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100
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2 4 6 8 10 12 14 16 18 20 22 24
CH
4, g/d
ay
Time after feeding, h
00.752.254.5
mg/kg BW
Exp. 1. Diurnal pattern of CH4 production from beef
cattle supplemented with different dose levels of NOP.
Treatment P-value1
0 0.75 2.25 4.5 SEM Trt L Q
Dry matter intake, kg/d 12.0a 11.7ab 11.3b 11.4ab 0.89 0.03 0.02 0.07
Total VFA, mM 160.5 159.1 148.4 147.7 9.13 0.16 0.04 0.41
Acetate, mol/100 mol 61.8a 60.8a 56.3b 52.6c 0.99 <0.001 <0.001 0.57
Propionate, mol/100 mol 19.3b 19.4b 21.4b 26.1a 1.16 <0.001 <0.001 0.23
A:P ratio 3.33a 3.23ab 2.74b 2.08c 0.21 <0.001 <0.001 0.76
Rumen fermentation of beef cattle fed a high forage diet
topdressed once daily with increasing levels of 3-
nitrooxypropanol (mg/kg body weight)
Romero-Perez et al. 2014 (
• No effects on total tract digestibility
Effects of feeding 3-nitrooxypropanol continuously for 112 d on methane production of beef cattle fed restrictively
63% 66% 51% 57% reduction
All animals received the
control diet in Recovery
NOP was mixed into the diet (60% forage DM)
(2 g/d)
Shifting H2 Utilization in the Rumen Using Nitrate
Nitrate is reduced to nitrite and then ammonia
Nitrate acts as an alternative H sink, competes with methanogenesis and lowers methane emissions
Source of dietary NPN
Potential for nitrite intoxication
Adaptation needed (gradual increases in nitrate in diets)
Slow release product
Nitrate (nitrite) Toxicity
Nitrate and nitrate can be absorbed into the bloodstream
Nitrite combines with hemoglobin to form MetHb, which is incapable of transporting oxygen to tissues
Mild poisoning: decreased feed intake and production (MetHb > 20%)
Clinical poisoning: brown mucous membrane discoloration, respiratory distress, and finally death (MetHb > 60%)
(Bruning-Fann and Kaneene, 1993)
Full reduction of nitrate to ammonia is a key to
maximizing the effectiveness of nitrate
Materials and Methods
• 8 ruminally-cannulated beef heifers (446 ± 21 kg BW)
• Replicated 4 × 4 Latin square design
• Nitrate source: encapsulated calcium nitrate (EN, 71.4% nitrate in DM; GRASP Ind. & Com. LTDA, Paraná, Brazil)
• Treatments (NO3-, % in dietary DM)
• Control (urea; 0.15 ± SD 0.03 % NO3-)
• 1% EN (0.94 ± SD 0.05 % NO3-)
• 2% EN (1.86 ± SD 0.15 % NO3-)
• 3% EN (2.48 ± SD 0.20 % NO3-)
• 14-d adaptation + 14-d sampling each period and 7-d ‘washout period’ between periods
• Gradual increases in EN in the diet by 1% every 4 days during the adaptation period
Encapsulated nitrate P value
Control 1% 2% 3% SEM TRT EN × h Cont vs. EN Linear Quad
DMI, kg/d 8.6 8.7 8.8 8.4 0.16 0.11 0.64 0.96 0.25 0.044
CH4, g/d 183 177 164 145 5.3 < 0.001 < 0.001 < 0.001 < 0.001 0.001
CH4, g/kg DMI 21.3 20.4 18.7 17.4 0.73 < 0.001 < 0.001 < 0.001 < 0.001 0.44
Enteric methane production
18%
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CH
4 p
rod
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ion
, g/k
g D
MI
Hours after feeding
Control
1% EN
2% EN
3% EN
Enteric methane produced (per kg DMI)
during 24 h in beef cattle fed once daily
Propionibacterium Strain
P-value Variable Control P169 P5 P54
DMI, kg/d 6.50 8.44 7.82 7.73 0.30
CH4, g/d 167 190 181 172 0.66
CH4, g/kg of DMI 25.7a 22.7b 23.5b 22.4b 0.02
Propionate, mol/100mol 20.3 21.3 21.0 20.4 0.72
Methanogens*,108 copies/g 8.46 8.55 8.56 8.30 0.18
Propionibacterium strains ( 5 x 109 cfu) supplemented to growing beef cattle fed a high forage diet (pulse dosed 1X/d)
Direct-fed Microbials: Bacterial Strains to Enhance Propionate Synthesis
Vyas et al. 2014 JAS
Propionibacterium acidipropionici strain P169
Propionibacterium acidipropionici strain P5
Propionibacterium jensenii strain P54
*16S rRNA, qPCR
Percent abundance of total Propionibacteria relative to total universal bacteria in ruminal samples from
beef heifers
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Control P-169 P-5 P-54
Rel
ativ
e ab
undan
ce, %
Treatments
0 h 3 h
9 h
P = 0.16 (T)
P < 0.01 (H)
P = 0.33 (T × H)
Vyas et al. 2013
Challenge : Supplemented strains of Propionibacteria have a low capacity to survive and integrate into the ruminal microbial community
Still more to learn
Time after feeding
Growing diets (55% silage)
Finishing diets (8% silage)
Methane and pH
Hunnenberg et al. 2015 JAS
CH4
CO2
methanogens
protozoa
H2
H2
Feed
bacteria
fungi
VFA methanogens
Rumen
Volatile fatty acids:
-------> acetate (produces H2)
-------> propionate (uses H2)
-------> butyrate (produces H2)
Methane Production is a Microbially Driven Process
Methanogenesis CO2 + 4 H2 ------> CH4 + 2 H2O
0.0
4.0
8.0
12.0
16.0
Australia, 1981-2010(Wiedemann et al., 2015)
Canada, 1981-2011(Unpublished data)
USA, 1977-2007(Capper, 2011)
30 years ago
Present
Change in GHG emissions per kg of live weight from
Australian, Canadian and USA beef sectors over the
past three decades
Sustainability – definition – everyone is happy?