I have never paid much attention to doomsday predictors, but even I know that the earth has a limited capacity and the growth of the human race shows no signs of slowing down. In November 2011, the global population reached seven billion people and is expected to reach nine billion by 2050! Sustainability is a buzzword that has gained worldwide attention. Finding a definition for sustainability can be more confusing than understanding the loyalty of a Leafs fan, but generally, sustainability has three key parts: environmental stewardship, economic viability, and social responsibility. For an industry to be sustainable, all three pieces need to be in place. If one factor is ignored or focussed on independently, then the system isn’t really sustainable in the long term.
Public opinion seems to be that animal agriculture uses an unreasonable amount of resources (both renewable and non-renewable) and is an alarming contributor to global warming in the form of green house gases (GHG). For example, a 2007 study cited agriculture as contributing 14% of global GHG emissions, which is more than the total emissions from burning fossil fuels for transportation! And that’s when farmers become enemy number ONE on the internet and I get that red face and twitch my family has come to recognise. While it’s true that growing food has an environmental cost, it’s NOT restricted to foods of animal origin. As we, in agriculture strive to maintain and improve food sustainability, we face criticism that that animal agriculture is an inherently inefficient method of food production.
If you’ve spent any time on the internet, you will have likely seen the suggestion that farmers are irresponsible hoodlums who should stop using valuable land growing food for animals and use it to grow people food – preferably kale and sprouts. It’s true that globally we are facing a growing food crisis during the next century. Worldwide, one in seven people have insufficient energy and protein to maintain health and undernutrition accounts for 12% of deaths worldwide. It has been suggested that one of the underlying issues is the so-called “feed vs. food” competition between animals and humans, but that isn’t really true at all. Although lots of foods that are suitable for humans can also be used as animal feed, animal feed and human food are not always interchangeable. In the quest to alleviate world hunger, activist groups often quote the statistic that one third of all cereal grains are fed to livestock. This leads to the, seemingly logical suggestion, that we should all stop being bloody, meat eating cavemen and switch to an earth loving, vegetarian diet. What they never tell you in this “feed vs. food” argument is that livestock diets include mostly crops and by-products from human food, fiber, and fuel production that are not suitable as human food and would otherwise be garbage…..
Some examples of commonly used feeds in North American livestock systems:
A wide range of food by-products are fed to animals depending on region, system, and animal species. It should be noted, also, that pastures used for livestock grazing are based on plants which are completely indigestible by humans. Estimates suggest that 70% of the world’s agricultural area is grassland. The majority of energy stored in these plants is in trapped as cellulose or hemicellulose, which are of ZERO food value to humans. Ruminants (cows, goats and sheep) are unique because they have a rumen with a tremendous microbial population that breaks down the plant cellulose and hemicellulose into simple sugars and, voila…. Turn inedible grasses into energy and protein, otherwise known as meat and milk.
The suggestion that animal agriculture should be abolished and that the global population could survive on a vegetarian or vegan diet is a narrow view and doesn’t consider the consequences of such a change. Most comparisons are based on swapping out animal based energy for plant based foods on the basis of total calories, without regard for supply of protein, vitamins, or minerals that you also get from animal-source foods. Nonetheless, there are numerous campaigns aimed at getting consumers to eat less meat, and, often quote a reduction in GHG emissions as the principal reason. The misguided folks behind the “Meatless Mondays” program, encourage consumers to forgo meat for one day per week, and claim they can decrease GHG emissions the equivalent of removing 20 million mid-size sedan cars from the road. The obvious piece they have missed is that a large-scale reduction in meat consumption not only would result in the replacement of animal products with plant-based foods, but additional sources would be required for the diverse by-products that come from animal agriculture, including leather, fertilizer and pharmaceuticals just to name a few. Take leather – replacing leather with hydrocarbon-based synthetics has a serious global environmental impact because it requires huge amounts of primary energy.
Until the 1950s, the majority of beef was raised using an entirely pasture-based systems and lots of urbanites and outspoken celebrities would like us to return to that. The move to rations containing a significant proportion of corn and by-product feeds is portrayed as an entirely negative development. The truth is that this shift has been a big plus not just for steak lovers, but also for precious mother earth. Average carcass weight, growth rate and feed efficiency have increased dramatically in the last half century resulting in less animals required to produce an equivalent amount of food. This is important relative to livestock’s environmental impact because every animal has a daily nutrient requirement for maintenance, pregnancy, lactation, or growth and thus associated resources (including feed, land, and water) and GHG emissions. The net result is that beef cattle today use 19% less feed, 33% less land, 12% less water, and 9% less fossil fuels than they did in 1977. The carbon footprint per kg of beef has improved by 16%! The pork and dairy industries have seen similar improvements.
Nonetheless, the reliance of intensive beef and dairy systems on fossil fuels and fertilizer inputs for feed production and transportation still leads to the suggestion that feedlots have a greater environmental impact than pasture-based beef operations. The reason this isn’t true is that cattle in feedlots convert feed much more efficiently. Numerous studies have demonstrated that GHG emissions per kg of beef are greater in pasture-finished systems than in feedlot systems, by as much as 20%.
Here’s where the animal feed industry makes its contribution. When grains or other vegetable ingredients are processed for human consumption, a significant portion is unusable and becomes a by-product. For example, when 1,000 kg of sugar beets are processed, the end result is 685 kg water, 140 kg of sugar and whopping 175 kg of feed only suitable for cattle…. That means that for every kg of sugar produced there is 1.25 kg of food for animals. Almost 70% of the ingredients used in livestock feed originate from the food processing industry as human inedible residues. As the world population continues to grow, livestock and poultry will be essential to recycle by-products that are inedible by humans into high-quality protein sources.
Fact – All foods have an environmental cost, not just food that comes from animals.
Fact – Global animal agriculture provides safe, affordable, nutrient-dense foods that support human health and well-being as part of a balanced diet.
Fact – Livestock production plays a significant role in the economic and social sustainability of developed and developing countries.
Fact – A significant proportion of land is incapable of supporting the production of human food yet forages can be efficiently converted by ruminant animals into meat and milk products.
Fact – The human food industry produces a vast amount of by-products that, if not fed to livestock, would be waste.
Fact – The gains made by recycling safe, yet otherwise valueless, by-products from human food production decrease competition between animals and humans for crops and reduce the environmental impact of food production
In a world where the global population is continually growing, the “feed vs food” myth will be pushed on us by well meaning vegans and environmentalist. We need to help them see that the use of by-product feeds in combination with management strategies that improve efficiency will, in fact help make animal agriculture a key pillar of sustainability. The challenge for us is to foster social acceptability and understanding of our industry’s contributions, thus advancing all three pillars of sustainability. It’s not as if we didn’t already have our hands full feeding the 9 billion…..
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