By 2050 an expanded world population will be consuming two thirds more animal protein than it does today, bringing new strains to bear on the planet's natural resources, according to a new report from the UN Food and Agriculture Organisation (FAO).
Populations and income growth are fueling an ongoing trend towards greater per capita consumption of animal protein in developing countries, says the report World Livestock 2011
. Meat consumption is projected to rise nearly 73% by 2050; dairy consumption will grow 58% over current levels.
Much of the future demand for livestock production - in particular in the world's burgeoning cities, where most population growth is occurring - will be met by large-scale, intensive animal-rearing operations.
"As it stands, there are no technically or economically viable alternatives to intensive production for providing the bulk of the livestock food supply for growing cities," FAO's report says.
But such systems are a source of concern due to environmental impacts such as groundwater pollution and greenhouse gas emissions, as well as their potential to act as incubators of diseases, warns the report, cautioning: "an urgent challenge is to make intensive production more environmentally benign."
Based on existing knowledge and technology, there are three ways to do this, according to FAO: reduce the level of pollution generated from waste and greenhouse gases; reduce the input of water and grain needed for each output of livestock protein; and recycle agro-industrial by-products through livestock populations.
The surge in livestock production that took place over the last 40 years resulted largely from an increase in the overall number of animals being raised. But "it is hard to envisage meeting projected demand by keeping twice as many poultry, 80% more small ruminants, 50% more cattle and 40% more pigs, using the same level of natural resources as currently," says World Livestock 2011
Rather, increases in production will need to come from improvements in the efficiency of livestock systems in converting natural resources into food and reducing waste.
This will require capital investment and a supporting policy and regulatory environment.
A number of additional challenges must be confronted as well, including drought, water shortages and other climate-related impacts - not to mention the threat of animal diseases, some which may directly threaten human health, which will have to be carefully managed as livestock production is ramped up.
Intensive systems, and those that encroach upon forest environments or peri-urban areas without proper hygiene, are a fertile ground for new diseases - and many of them are managed in ways that are detrimental to animal health and welfare, according to the report.
"It is not enough to pour funding into coping with the urgent disease threats of today - disease intelligence and epidemiological research must be financed to anticipate future diseases in the countries that produce the bulk of livestock source food," it says.
Since 1967, global production of poultry meat increased by around 700%. Other products saw surges in production as well, including eggs, which registered a 350% increase, pig meat (290%), sheep and goat meat (200%), beef and buffalo meat (180%) and milk (180%).
Livestock products today supply 12.9% of calories consumed worldwide - 20.3% in developed countries. Their contribution to protein consumption is estimated at 27.9% worldwide and 47.8% in developed countries.
However global trends have not played out evenly on the ground. In many places, production increases haven't occurred and poor and vulnerable communities have not seen their consumption of animal protein rise, FAO warns. Production has expanded rapidly in East and Southeast Asia and in Latin America and the Caribbean but growth in sub-Saharan Africa has been slow.
"Average consumption of livestock protein in Africa is less than a quarter of that in the Americas, Europe and Oceania, and represents just 17% of the recommended consumption level for all proteins," says FAO's report. "By contrast, the consumption of livestock protein in the Americas, Europe and Oceania in 2005 was between 78 and 98% of the total protein requirement, suggesting that livestock products are being over-consumed."
But in the developing world, livestock and livestock products can make a crucial contribution to household economic and food security - as well as nutrition.
Even small amounts of animal source foods can improve the nutritional status of low-income households. Meat, milk and eggs provide proteins with a wide range of amino acids as well as micro-nutrients such as iron, zinc, vitamin A, vitamin B12 and calcium, in which many malnourished people are deficient.
For livestock-dependent pastoral societies like those in Eastern Africa, the report says, priorities should be boosting the sector's contribution to food security by restoring degraded pastures and managing them better, strengthening animal health services, and doing more to help livestock keepers get their animals and goods to market.
Source: UN Food and Agriculture Organisation