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MEKARN Workshop 2009: Livestock, Climate Change and the Environment |
The Green Revolution began with the development and rapid dissemination of cereal grain varieties with potentially enhanced yield. The yield increases were immense (up to 10 fold) when the selected grain verities were grown with additional inputs, including increased use of artificial fertilizers, application of modern insecticides, increased access to irrigation water and a change from draught power to the use of tractors, often increasing annual crop off take by one crop per year. The Green Revolution appeared to be set to extinguish world food poverty. The increase in availability of world grains that resulted provided annual carry over stocks, surplus to world need and whilst some of the least privileged still went hungry, the availability of cereal grain that was inexpensive, resulted in a massive development of grain based, intensive meat production from pigs poultry and beef cattle and milk production from cows mainly in industrialized countries. Optimum production from cereal based diets was the primary object of much of the animal production research over the last four decades
The consequences of the Green Revolution were major population increases (now unsupportable with present day resources), rapid depletion of finite resources (fossil fuel and water, land fertility and availability and phosphate fertilizers) and has added to the green house gas emissions causing global warming.
World food production is entering an era where overall it is likely to decline from a number of changing conditions and there will be increasing competition for scarce resources to produce food, feedstock for biofuel and plastics industries and feed for livestock. It is most likely that the feed deficiency will hit the livestock industries hardest and costs of factory farming will escalate and production will decrease.
For wealthy people, meat and milk are foods of choice which are often over consumed. For the poor, mainly in developing countries that depend on diets based largely on cereals, meat and milk are essential dietary components to balance diets for normal health. The modern high yielding grain varieties have increased these requirements as they are much lower in micro nutrients that are critically deficient in the traditional cereal grain varieties.
Factory farming of animals based on cereal based diets will inevitably become more expensive and therefore unavailable to a large proportion of impoverished people. The demand for animal protein from a nutritional health aspect will be increased. The future of animal protein production appears to be with the herbivorous species that are capable of utilizing cellulosic feed not usable by monogastric animals and which are often byproducts of food crop production. The paper discusses the many possibilities of integrating herbivorous animals with cropping and the potential of selecting appropriate species including ruminants, rabbits, fish and pigs according to their comparative digestive capacities and their ability to be incorporated into sustainable farming systems.