FOR poor people everywhere, meat equals prosperity. In 1930s America, “a chicken in every pot” ranked as an electoral promise alongside “two cars in every garage”. And today, as trade and industrialisation raise living standards across the globe, people are using their new prosperity to do what the poor have always done when they could: eat more animal protein. For most, this means a scrap of pork in the family wok, not a thick, juicy steak. Even so, the consumption of meat, milk and eggs is skyrocketing.
People in developing countries now eat 50 per cent more meat per person, on average, than they did in 1983, despite increasing population, according to the UN Food and Agriculture Organization (FAO). Much of it is home-grown: production in developing countries has almost doubled in that time. Some say this marks the start of a “livestock revolution”, as significant as the Green Revolution that boosted grain production in the 1960s.
“The livestock revolution is inherently neither good nor bad,” says Chris Delgado, an economist at the International Food Policy Research Institute (IFPRI) in Washington DC. “But it will happen.” Yet some agronomists and economists fear it is a recipe for disaster. Producing more meat is likely to mean feeding more grain to animals. But people also eat grain. So the problem is this: can we grow enough grain to supply more intensively farmed livestock without taking food from the mouths of Earth’s poorest people?
Advertisement
The attractions of meat are obvious. Many people in developing countries – especially women and children – lack the protein and trace elements such as iron found in meat, milk and eggs. While it’s possible to get a complete diet without animal foods, says Delgado, “it requires a large diversity of crop foods that are typically not available all at once at low cost to poor people in developing countries.” Animal protein also boosts the nutritional value of vegetable protein. So for most, an egg, some cheese, or a little mutton or pork is the easiest – and tastiest – path to better nutrition. And most of the world’s people have plenty of room on their plates for a little more meat. Even in China, which leads the revolution and where per capita meat consumption doubled between 1983 and 1993, people eat on average just a quarter as much meat as a typical American.
The key question is how much grain is needed to produce this extra meat. Traditionally, farm animals have eked out the harvest by eating things humans do not – grass, crop by-products such as straw, food wastes and surpluses – and turning them into food and manure for the fields. Much of the increase in meat production in developing countries so far has been fuelled by such feeds. But like their colleagues in rich countries over the past fifty years, many Third World farmers are finding it easier and cheaper to feed their animals on grain. This provides concentrated calories, and allows more efficient metabolism of other foods, notes Lee Baldwin, an animal scientist at the University of California at Davis.
Predicting what increased meat consumption will mean for grain supplies is no easy task. World agriculture is a complex system, and farmers produce whatever seems most profitable. So long as grain continues to be cheaper than the meat it produces, livestock farmers will use it to expand production, says Jim Oltjen, another animal agriculture specialist at Davis. And reckoned purely in terms of calories, we lose out when this happens. Livestock fed a typical Western mix of grain and human-inedible feed such as grass and silage produce a calorie of meat for every three calories of grain they eat, according to a study last year by the Council on Agricultural Science and Technology (CAST), an umbrella group of agricultural research societies in the US.
The use of grain for feed grew 50 per cent in the developing world between 1983 and 1993, and increased faster than overall grain production in nearly every developing region. That’s one reason China dropped its goal of food grain self-sufficiency last year, says Oltjen. Today, intensively farmed animals eat 36 per cent of the world’s grain harvest, according to estimates from IFPRI. Meanwhile, 840 million people are chronically hungry – a number that may increase if the world feeds more grain to livestock. “Grain production is unlikely to rise fast enough to satisfy projected demand for both food and feed,” says Lester Brown of the Worldwatch Institute, an environmental think tank in Washington DC.
Delgado and his colleagues at IFPRI have used a global model called IMPACT to forecast how all this might affect world food production. Starting with the growth rates for population, income and urbanisation in every country – the main factors affecting demand – plus food and feed prices, rates of technological change, and other factors, IMPACT calculates food and feed consumption, and future prices, year by year.
The model predicts that by 2020, each person in developing countries will eat 43 per cent more meat on average than in 1993. With population growing as well, that means annual meat consumption in the Third World will soar from 88 to 188 million tonnes by 2020 (see Diagram). With consumption in rich countries relatively static, worldwide meat consumption will rise by 1.8 per cent per year.FIG-mg22304301.JPG
Some of that increase will come through the use of human-inedible feeds, but IMPACT predicts that grain consumption by the world’s livestock will rise 1.4 per cent per year over the same period. The good news is that this may not force up grain prices very much: at most, the model predicts increases of 11 per cent for rice and wheat and 20 per cent for maize. That would still leave grain prices lower than they were in the 1980s, so most poor people should still be able to afford it. (Of course, this broad generalisation skips over many local or regional problems that also contribute to hunger.) Even better, says Delgado, if governments adopt policies, such as easy credit, that put a lot of that meat production into the hands of families, rather than huge companies, many poor people may actually have more money to buy food.
Pigs or people
But IMPACT’s reassuring prediction is based on an important assumption – that global grain production can rise by 1.3 per cent per year between now and 2020. Without that increase, there will not be enough grain to satisfy demand, and grain prices will rise. Livestock farmers would still be able to sell their meat to the wealthy, and so would be able to outbid the poor in the market for the scarce grain. Then people could starve so that pigs and chickens might eat.
At first sight, that assumption doesn’t look good. World grain production did rise by 1.3 per cent per year in the 1980s. But since then, the average rise has been only 1.1 per cent per year, and IFPRI itself forecasts that this average increase will continue until 2020. Delgado says the rate could be increased by pushing more land into production in Asia, and using more fertiliser on rain-fed crops in North America. Others warn that we may be running out of ways to boost production. Existing grain varieties are already close to the biological maximum plants can manage, says Kenneth Cassman, a former head agronomist at the International Rice Research Institute in the Philippines who is now at the University of Nebraska at Lincoln.
This, Cassman says, makes further big gains from plant breeding unlikely. “The private sector invests four times more in maize improvement now than it did 20 years ago,” he notes, yet yields are not climbing any faster. The best hope for improvement, says Cassman, may lie in painstakingly tailoring water, fertiliser and pest control to each hectare, so that every plant achieves its biological potential. In much of the developing world, however, the money, materials and education to do this are lacking.
But growing more grain to feed to animals is not the only way of increasing meat production. If livestock could be made to use feed more efficiently, farmers could produce more meat from the same amount of grain. Pigs and chickens are already bred for feed efficiency. A modern intensively raised chicken will put on 3 kilograms from the same amount of feed that in 1957 yielded only 2 kilograms. But till now, cattle breeders have had other priorities, says John Basarab of the Canadian government’s Lacombe Research Centre in Alberta. Beasts bred for North American feedlots, for example, have been selected for big appetites and rapid weight gain rather than efficient use of feed, he says. They could be improved. But breeding improved cattle for the tropics will require locally adapted cattle varieties, which are disappearing. The FAO is now trying to save them.
Using the IMPACT model, Delgado assessed what would happen to the global grain requirement if researchers put additional effort into raising the feed efficiency of livestock by an extra 0.5 per cent per year in rich countries, and 1 per cent per year elsewhere, between now and 2020. That extra boost, over and above the probable increases Delgado assumed in his basic model, reduced the global increase in demand for grain to only 1.1 per cent per year. That makes the picture look rosier, because 1.1 per cent is the rate at which grain production is growing now.
These higher targets for increased food efficiency look achievable, maybe even conservative. “In some places, like China, efficiency could rise faster,” says Oltjen. Between 1983 and 1993, for example, CAST estimates that grain efficiency of animal production climbed 1.5 per cent per year in both rich and poor countries. But Delgado cautions that the predicted gains from increased efficiency could quickly be eaten up if farmers adopt grain as feed even slightly more quickly than expected.
There are high-tech ways to make animals more feed-efficient. Pigs injected with DNA that encodes a modified, long-lasting releasing factor for growth hormone grow 40 per cent faster on 25 per cent less feed, Robert Schwartz of Baylor College of Medicine in Houston reported in December (Nature Biotechnology, vol 17, p 1179). And an adrenalin-like drug called ractopamine, which the US-based firm Elanco started marketing this year under the name Paylean, makes pigs grow muscle rather than fat. Muscle requires less feed. The amount of grain that would have made 3 kilograms of fat makes 5 kilograms of lean meat instead – and does it more quickly.
Another way to help animals make efficient use of feed is to ensure that it matches their nutritional requirements. Several companies have bred maize varieties that produce more lysine and methionine, amino acids that are lacking in grain. The protein in these varieties is closer to the nutritional requirements of chickens and pigs than protein in ordinary maize. Unlike earlier varieties of high-lysine maize, these strains pack the amino acids into the germ instead of the less digestible storage protein called zein, allowing animals to digest them more easily, says Jerry Weigel of ExSeed Genetics of Owensboro, Kentucky. That means the animals don’t need to be fed so much expensive protein supplement.
Improved efficiency has other benefits. As farmers rear more cattle, sheep, pigs and chickens, the animals’ manure poses an increasing environmental problem. But when livestock make more complete use of their food, less comes out the other end. Elanco estimates that Paylean could reduce the amount of manure pouring out of America’s pig farms by some 2 million tonnes a year. More digestible food also means that fewer nutrients pass into the manure, so it causes less pollution and less stink.
Amazing maize
As well as protein and calories, animals need the element phosphorus. Normal maize contains much of its phosphorus in the form of phytic acid, which animals cannot digest and which is excreted in their manure, adding to pollution. Several firms have now bred low-phytic maize, containing phosphorus in a more digestible form. Animals eating it need less phosphorus supplement in their diet, excrete less phosphate, and can digest protein – which is normally bound by phytic acid – more completely. The British-based company Zeneca Agrochemicals has engineered genes for an enzyme that destroys phytic acid into rapeseed, which is used as feed. It also produces the enzyme as a feed additive.
Adding enzymes that break down cellulose and other plant fibres can help animals extract more food value from low-grade feeds such as hay. Even in cattle – whose digestive systems naturally contain bacteria that break down such fibres – these enzymes can boost feed efficiency by producing sugars that encourage the bacteria to multiply, digest fibrous feeds more completely, and reduce the animals’ need for grain. Researchers at the Lethbridge Research Centre in Alberta, Canada, are engineering genes for the enzymes into forage plants so that cattle can get them on the range as well as in the feedlot.
If grain becomes more expensive, farmers may start feeding cattle and sheep more materials now considered wastes, predicts Ed Charmley at the Canadian government’s research farm in Nappan, Nova Scotia. Potato tops can be fermented in silos to make them more digestible and destroy some of the toxins. Compostable wastes from food processing, sorted household trash and even crab shells could be used.
Forecasts such as those by IMPACT will never be completely accurate, Cassman warns. But the predictions tell us one thing: unless the rich forswear meat, the world will need both more efficient livestock and more grain to produce enough for all. That means improving agricultural technology. Yet investment by rich countries in research that will benefit poor countries has been falling or stagnant since the 1980s, reports IFPRI. For example, more wastes could be developed as feed – but, warns CAST, funding for research has been “very limited”. Agricultural research overall has passed increasingly into the hands of private companies, whose priorities are not necessarily those of developing countries. Direct American aid for agriculture in poor countries fell by 63 per cent between 1986 and 1994, according to IFPRI.
But that aid is needed if poorer farmers are to take part in the livestock revolution. This would benefit everyone. These farmers are best placed to recycle manure as fertiliser, they would benefit most from the extra income, and their small-scale meat production avoids some of the problems on bigger farms, such as the risk of disease in huge herds. But some Western pressure groups oppose investment in animal production in poor countries, claiming that it wastes grain or is otherwise unethical. And some governments would rather export meat than encourage Third World countries to produce their own.
Delgado thinks this is misguided. “No one can stop people eating more meat and milk,” he says. He would like to see research focused on helping poorer farmers to provide it. “If demand bypasses local farmers in favour of large, urban animal production factories, it could ensure that the livestock revolution will be a curse rather than a benefit.” This is a mistake that we still have time to avoid.
