Greenhouse Gases and Animal Agriculture Finding a Balance Between Food and Emissions

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1 Production Driven ($) Greenhouse Gases and Animal Agriculture Finding a Balance Between Food and Emissions Karen Beauchemin Lethbridge Research Centre, Lethbridge, Alberta, Canada Relative magnitude Environmental Impact GHG Livestock Production Contributes Significant Greenhouse Gas Emissions Globally, livestock production accounts for: 8% of GHG (EPA, 26; IPCC, 27) 18% if land use and land use change is accounted for (FAO Livestock s Long Shadow Report, 26) Meat and dairy products account for about 5% of foodgenerated GHG emissions (Garnett, 29) Livestock - A Key Global Commodity Supplies 17% of calories, 33% of protein globally Ruminants use pastures, byproducts (human inedible) Income support: esp. 1 billion people in low income countries Small holdings, Little need for land ownership or education Low investment FAO, 21 Herrero et al. 29 COES 1:111 Expected Demand for Livestock Products Expected Demand for Livestock Products 25 2 Per capita consumption (kg/d) Milk Doubling of demand for meat and milk (2 to 25) 7 6 Total consumption (Mt) Milk High Income Countries Meat Milk Meat Low Income Countries Year Milk Low Income Countries Meat Year Meat High Income Countries 1

2 Expansion of Global Livestock Production Demand Drivers Global population growth Urbanization Wealth Socio-Economic Limitations Costs (feed, fertilizer, fuel, labour) Carbon constrained economy (GHG) Limited land resources Competition for water resources Animal welfare, others Food and Agriculture Organization Projections: 23 versus 1997 Increasing demand for food will increase global agricultural emissions CH 4 emissions: + 6% Livestock N 2 O emissions: + 5% business as usual approach not acceptable future expansion limited by environmental, social and economic constraints Global Livestock Industry Diversity Given the importance of livestock, and its expected continued growth, how CAN we attenuate the future increase in GHG emissions? Food security issues dominate Small holder dairy farm in India Cannot use a one-size-fits Land-less nomadic system all in Sub approach Saharan Africa to lowering GHG emissions If it costs more, who will pay? Small family farm in Wisconsin Land-less feedlot system in California Balancing Livestock Production and GHG Emissions Meat/milk demand Waste (1/3 of food in high income countries) Consumption in high income countries 6% decrease in consumption = 15-2% reduction globally (Garnett, 29) Environmental cost of substitutes (e.g., pasture to crop land? Importation?) Efficiency ( GHG/food) Resource use / food Emissions / food Efficiency: GHG Intensity (Carbon Footprint) GHG emissions (kg eq) Kg product Nitrous oxide (GWP=298) + Methane (GWP=25) + Carbon dioxide (GWP=1) Functional unit kg fat-protein corrected milk kg carcass kg protein, MJ energy 2

3 Life Cycle Assessment Life CH Cycle 4 N Assessment 2 O Cradle to grave analysis Determines how a change in management/diet transfers through entire Farm system Processing Retail 1 kg live wt plant transportation U.S. Fluid Milk Carbon Footprint: Supply Chain Emissions Transport/Distribution Packaging Processing Consumer Retail 4.9% 6.5% 7.7% 3.5% 5.7% Feed Milk production 51.5% 59% enteric methane 35% manure methane 6% electricity Farm (72%) Fertilizer Pesticides Herbicides Packaging Feed production 2.3% 64% Soil N 2O 24% fert. 12% fuel use Life Cycle Assessment System boundary - cradle to farm gate Sources of GHG Emissions from Livestock Production CH 4 N 2 O Farm 1 kg live wt transportation Processing plant Retail Fertilizer Herbicides Feed Pesticides 7-9% of total emissions Packaging Sources of GHG from Production in Western Canada (estimated using HOLOS) Source of Emission by Sector of Production System (estimated using HOLOS) Life cycle emission breakdown ( eq) Manure N 2 O Energy Soil N 2 O 5% 4% 23% 63% Life cycle emission breakdown ( eq) Feedlot 2% 5% Enteric CH 4 Cow-calf herd 8% Manure CH 4 Beauchemin et al. (21). Agr. Syst. 13: Beauchemin et al. (21). Agr. Syst. 13:

4 Sources of GHG From Dairy Production in Eastern Canada (est. using HOLOS) GHG Intensity of Livestock Products ( eq / kg carcass or milk, farm gate) Life cycle emission breakdown ( eq) Soil/Crop N 2 O Energy Soil 2% 2% Indirect N 2 O 7% 26% 48% Enteric CH 4 e/kg product 3 2 Feed efficiency Enteric methane Reproductive cycle These LCAs do not account for C sequestration or losses due to LUC 1 7% 8% Manure N 2 O Manure CH 4 McGeough et al. (212). J Dairy Sci. (in press) pork chicken beef milk eggs From devries et al. 21. Livest. Prod. Sci. 128:1-11 The Ruminant - GHG Conundrum Use of non-arable land and inedible cellulosic material Maintains grazing lands - important for wildlife habitat, watershed management, recreation, etc. Pastures help maintain soil carbon 2) Reducing inputs and inefficiencies Making better use of resources 3) Intensification Increasing milk and meat production (i.e., more food per unit of GHG produced) Focusing ONLY on GHG emissions doesn t give the full picture!!! Methane Production in the Rumen Rumen VFA methanogens methanogens H 2 H 2 CH 4 Feed fungi bacteria protozoa Methanogenesis 4H 2 + CH 4 + 2H 2 O 4

5 CH 4 -Chamber, g/d Methane Emission and Dry Matter Intake beef cattle Canadian 5 Australian Dry matter intake, kg/d dairy cows diet/feed animal digestion Grainger et al. 27. J. Dairy Sci. 9:2755. photo by Julia Palmer Animal Breeding Low Methane Diets High vs. low methane emitters Realistic given other breeding objectives? Genetic selection of efficient animals (eat less, produce the same) Efficient cattle produced 24% less methane/kg gain (Hegarty et al. 27. JAS 85:1479) Relative Feed Intake per Carcass Produced (energy basis) Wirsenius 23. Agric. Sys. 77: Edible Non-edible (cellulosic) World Pig North America Sub- Saharan Africa Pig Pig Cereals, starchy roots, soybean, pulses Hay, silage, other forage crops Cropland pasture Permanent pasture Crop residues Food processing by-products, food waste World Pig Ruminants Enteric methane lower for grain vs cellulosic diets Feeding grain decreases methane and (in most cases) total GHG emissions/product need to use a LCA Not consistent with niche role of ruminants of converting high fiber feeds to meat/milk 5

6 Reducing Enteric Methane from Non-Edible (cellulosics) Edible Non-edible (cellulosic) World Pig Maturity effects (fiber) Legumes vs. grass Sainfoin Tannin-containing (LRC 3519) legumes High starch forages (maize, cereal silages) High sugar content grasses (Ireland) High lipid content ryegrass and clover (NZ) Oilseeds, High-fat Byproducts Boost the lipid content of the diet (up to 4-6%) 4-5% reduction in methane (g/kg DMI) /1% added lipid Diverse mode of action Sources: Oilseeds (e.g., canola [rapeseed], linseed, sunflower) Byproducts (e.g., corn distillers grains) Adding Ground Oilseeds (3% added fat) to Diets fed to Lactating Dairy Cows Methane Control Linseed Canola (rapeseed) Dry matter intake, kg/d 18.7 c 19. bc 2.1 a Milk, 3.5% fat Methane, g/d 293 a 241 b 265 b Methane, g/kg DMI 16.3 a 13.4 b 13.7 b 16-18% reduction (Beauchemin et al., 29. J. Dairy Sci. 92: 2118) Modification of Rumen Mircoflora and Fermentation Microbials Yeast Bacteria Vaccine Rumen Microbes and Fermentation Biochemical H sinks inhibitors Secondary plant components Bacteriocins (toxins) and bacteriophage (visus) Supplementation of Cattle diets with an Anti-methanogenesis Compound % reduction Dose (mg/head/day) g CH 4 /kg DMI DMI (kg/d) (Beauchemin et al., unpublished) 6

7 Reductions in methane emissions: What is feasible? % reduction in e/kg carcass Example approaches: Efficient cattle (genetics) Improved forage quality Supplemental lipids Rumen fermentation additive 2) Reducing inputs and inefficiencies Making better use of resources Improving Efficiencies: Animal Management Example: Longevity of dairy cows in the herd Culling due to reproduction, heath, etc. affects replacement rate (need for replacement heifers) Replacement Rate GHG (kg /kg FPCM) 22%.66 37% (mean).96 ±3% 51% 1.39 Estimated for a Canadian dairy farm (211); no allocation Reducing Inputs: Cradle-to-Farm Gate LCA of Milk Production in Norway (Bonesmo et al., unpubl.) kg eq kg -1 FPCM Enteric CH 4 Soil N 2 O Proportional to inorganic fertilizer use Total GHG emission, kg eq kg -1 FPCM 2) Reducing inputs and inefficiencies Making better use of resources 3) Sustainable intensification Increasing milk and meat output (i.e., more food per unit of GHG produced) Sustainable Intensification The key is to develop sustainable intensification methods that improve efficiency gains to produce more food without using more land, water, or other inputs (Herrero et al. 21 Science 327:822) 7

8 Comparing Environmental Impact of U.S. Industry in 1977 to 27 (J. Capper, Washington State University) Comparing Environmental Impact of U.S. Industry in 1977 to 27 (J. Capper, Washington State University) 1977 level 1977 level Figure from J Capper, Wash State Univ. Figure from J Capper, Wash State Univ. Intensification in Low Income Countries? Simply adopting a western approach is not an option Mainly small holder mixed farms (land livestock) Bigger not necessarily better Animal genetics of adapted breeds Feed supply critical Crop residues and by-products 5-7% of feed inputs Need technology to improve feed yield, increase digestibility Finding a Balance Between Food and GHG Emissions - The Way Forward Inputs Emissions Emissions Products Inputs Using resources more efficiently Products Wright et al J Sci Fd Ag 92:11 Scientists Young scientists to take on the challenge Aimable Uwizeye MS student, Rwanda Divakar Vyas Post Doctoral Fellow, India Livestock producers Reducing GHG Emissions? Social scientists Atmir Romero Perez PhD student, Mexico Martin Huenerberg PhD student, Germany Emma Mc Geough Post Doctoral Fellow, Ireland Atitthan Nanon PhD student, Thailand Consumers Governments Paul Escobar Bahamondes PhD student, Chile Noppharat Phakachoed PhD student, Thailand Economists Riaz Mohmmed Post Doctoral Fellow, India Joseph Lynch Post Doctoral Fellow, Ireland 8

9 211 Bertebos Prize Established Animal Science Environmental Sustainability Scholarship At Kwame Nkrumah University of Science and Technology (KNUST), GHANA recipient - 9