Consumers have increased interest in sustainable diets. Conflicting information from various resources has these consumers viewing sustainable diets as eating less meat.
Dr. Kim Ominski with the University of Manitoba presented during the virtual Animal Nutrition Conference of Canada about improvements in animal environmental impact.
Why it matters: The future livelihood of livestock farmers hinges on continued support from consumers.
The Food and Agriculture Organization (FAO) defines sustainable diets as diets with low environmental impacts that contribute to food and nutritional security and to a healthy life for present and future generations.
“The sustainability of animal diets has been criticized with an emphasis on the adoption of plant based diets to decrease greenhouse gases, decrease land use and improve human health,” says Ominiski.
A study completed by Robin White and Mary Beth Hall in 2017, showed the removal of livestock production from U.S agriculture was not completely sustainable as the livestock industry employs 1.6 million people and accounts for $31.8 billion in exports.
“They observed that animal derived food products provide approximately 24 per cent of energy and 48 per cent of protein available for human consumption in the United States,” said Ominiski.
As well, livestock have the capacity to recycle more than 4.3 billion kilograms of human edible food and fibre processing byproducts by converting them into food edible for human consumption, pet food, industrial products and nitrogen fertilizer.
“I think we all acknowledge that it’s important that consumers have choices with regards to the foods that they consume. However, it’s often difficult to communicate the implications associated with those choices, specifically in terms of the environmental impact or the environmental sustainability.”
The increased interest in environmental sustainability by consumers has led to the study of the environmental footprint of both animal and plant based commodities; an evaluation of the sustainability of these products, including greenhouse gas creation, nutrient cycling, water use and air quality.
A study completed by Legesse et al. shows beef production in Canada in 2011 required 24 per cent less land than in 1981. As well, the beef produced had a 15 per cent smaller carbon footprint than 1981.
In addition to greenhouse gases, beef production, within the same 30-year time frame, showed an increase in total water use by 30 per cent, but a decrease in the water use intensity (litres of water per kilogram of boneless beef) by 17 per cent.
This same study found that the ammonia emissions in Canadian beef production in 2011 relative to 1981 increased but there was a decrease in ammonia intensity (kg of ammonia per kilogram of beef) by 20 per cent.
Looking at the dairy industry, a study completed by Jayasundara and Wagner-Riddle in 2014, showed that the production of fat and protein corrected milk (FPCM) from 1991 to 2011, has increased by 43 per cent in terms of milk production in kilograms per cow per year.
As milk production increased in this timeframe, it was found that both the enteric methane emissions, expressed as kilograms of CO2 per kilogram of FPCM produced, and total greenhouse gas emissions, expressed as kilogram of CO2 per kilogram of FPCM produced, decreased by 22 per cent.
Within the egg industry, a study completed by Pelleteier et al. found an increase in egg production from 1962 to 2012 with a decrease in greenhouse gas emissions by 57 per cent, a 71 per cent decrease in land use and a 53 per cent decrease in water use.
“The improvements (in all these commodities) have been realized both in terms of animal performance, but also in terms of crop yield, and irrigation efficiency,” says Ominski.
The study on beef production showed that reproductive efficiency improved by 15 to 45 per cent between 1981 and 2011.
As well, this study found that the improvements in feed crop yields and irrigation efficiency within grain barley, grain corn and barley and corn silage have all increased by 23 to 61 per cent.
A study completed by Gerber et al. in 2011, and McAllister in 2020, found that in regions of the world where production efficiency is much lower, emissions tend to be higher.
“If we use the example of kilograms of CO2 per kilogram of milk, we can see that the global average is 2.5 kilograms of CO2 equivalent, but the Canadian average is much lower at 0.92 kilograms of CO2 equivalents per kilogram produced,” says Ominski.
Consumers also need to think about livestock sustainability in terms of the circular economy.
Livestock essentially produces food and other products for human consumption but their manure production greatly contributes to improving soil quality.
“The byproducts associated with processing of many of those plant products for example, can also cycle back into livestock production or indeed can be used for bio energy production,” says Ominski.
It’s also important to note that livestock provide the availability to graze on more than one third of the Canadian landscape not suitable for crop production.
“These statistics line up closely with what we see reported by the FAO on a global basis. Eighty-six per cent of the global livestock feed intake in dry matter consists of feed materials that are not currently edible for humans and 57 per cent of the land used for feed production is not suitable for food production,” says Ominski.
She says it’s important for consumers to note that the value of livestock greatly extends beyond nutrition in developing countries.
Global waste of food is a role in which all consumers play in environmental sustainability of agriculture production systems.
“Thirty per cent of cereals that are produced are lost as food waste. Almost half of fruits and vegetables. Almost half of roots and tubers, 20 per cent of oilseeds and pulses, 20 per cent of dairy products, 30 per cent of fish and seafood and 20 per cent of meat,” says Ominski.
There are 35.3 million tons of food in Canada wasted annually, but 32 per cent of this is deemed avoidable and accounts for close to $50 billion.
“In the agriculture sector as stakeholders, we all want to share our knowledge with the general public,” says Ominski. “We know it’s important that we provide science-based information so that consumers can make informed choice, and we have the luxury here in Canada to have many organizations which have championed that cause.”