Agriculture Reference
In-Depth Information
16
Manipulation of Microbial Ecology
for Sustainable Animal Production
A.-D.G. Wright* and S.E. Hook
Department of Animal Science, University of Guelph,
Ontario, Canada
Introduction
As we look for opportunities to feed a grow-
ing population, waste and inefficiencies in the
current agricultural systems will not be accept-
able in 2050. Furthermore, current agricul-
tural and food production practices contribute
significantly to the global problem of green-
house gas emissions. Therefore, a multifunc-
tional approach to agriculture will be required
to significantly increase food production sus-
tainably using the existing land area and water
resources. Broadly speaking, multifunctional
agriculture means that agricultural activity,
beyond its role of producing food and fibre, may
also have several other roles such as renewable
natural resources management, landscape and
biodiversity conservation and contribution to
the socio-economic viability of rural areas
(Renting
et al
., 2009).
The increasing demand for food from ani-
mal sources, especially in the developing coun-
tries, will lead to a continued high interest in the
interaction of livestock with the environment.
About 25% of the world's land is used exclu-
sively for grazing livestock, accounting for nearly
30% of the cattle and 35% of the sheep and
goats (Seré
et al
., 1996). Furthermore, most of the
rest of the world's approximate 1.1 billion rumi-
nants (FAO, 2000) are reared in mixed farming
systems where grazing is complemented with
The world's human population will grow from
almost 7 billion people to over 9 billion in 2050.
The projections show that feeding a population
of 9 billion people would require increasing
overall food production by some 70% between
now and 2050 (FAO, 2009). Accordingly, pro-
duction in the developing countries would need
almost to double (FAO, 2009). As the world's
population increases, so do problems associated
with food security, land use and social and envi-
ronmental issues (Parker, 2011). In the past,
increases in the demand for food were achieved
by bringing more land into production, but the
amount of land required to do so is not realistic
given the projected trends in population growth
(Smith
et al
., 2010). For example, it has been
estimated that the availability of new arable
land necessary to provide food for the world's
growing population would require the clearing
(i.e. deforestation) of 900 million additional hec-
tares of land (e.g. nearly one-third of the con-
tiguous USA) just to maintain the current
caloric levels (Biello, 2011), or 2.1 billion addi-
tional acres (e.g. about two-thirds of the contig-
uous USA) to meet the necessary caloric levels of
the world's population. Yet, land area is less of a
limitation than the availability of water.
