|ADDITIONAL READING AND LINKS
Benefits of Grass Fed Beef
Another of Dr. Joseph Mercola
(Wellness Center) excellent pages summarizing the environmental costs of
industrial meat production (beef, pork and chicken). Well referenced,
easily scanned page.
ruminants on top for energy efficiency; Pigs & poultry fare poorly
due to high grain & housing inputs
by Hugh Maynard at
REAP. Resource Efficient Agricultural Production (R.E.A.P.) -
Canada is an independent, non-profit organization that has been working
since 1986 with farmers, scientists, non-governmental organizations, and
industry, to advance the development of sustainable farming systems.
What an animal takes in and puts out as
energy has long been a popular item of discussion. Economically, the input/output
ratio determines the profitability of the farm. Environmentally, the use
of non-renewable resources and demands on the sustainability of farmland
are increasingly more important.
Alan Fredeen and Peter Havard of the Nova
Scotia Agricultural College presented their findings regarding this question
to the NSAC symposium on sustainable agriculture entitled "Reducing the
Non-renewables", last April in Truro. Respectively members of the Departments
of Animal Science and Engineering, their research has been aimed at examining
the relationship between the input of non-renewable energy and the output
of useful energy with the goal of identifying areas for improvement.
They defined the non-renewable energy inputs
to animal production as the energy equivalent of fuels for operating machinery
and ventilation, drying crops, production of inorganic fertilizers, and
production of machinery and buildings.
Energy outputs were defined as the energy
equivalent of human edible products of animal production and animal wastes
used as fertilizer.
"Utilization of non-renewable inputs is
currently not governed by efficiently. Their use is based on supply and
price," the authors noted, adding that there has become the necessity for
conservation, both for sustaining development and limiting damage to the
They identified two approaches for improving
the efficiency of animal production: the traditional approach is to increase
inputs, taking advantage of the essentially fixed requirements for maintenance
in animal production; the alternative approach is to lower energy inputs,
such as switching from warm to cold housing or using natural ventilation
Using work done by Southweil and Rothwell
in Ontario in 1977, the authors presented production efficiencies from
non-renewable energy inputs. They ranged from a low of 0.23 (output over
input) for poultry (meat) to a high of 1.65 for heavy lamb.
"Efficiency seems to be affected most by
housing design and by cereal grain input. Beef and sheep production systems,
with potentially lowest housing and grain inputs, are most efficient" they
stated. Beef energy output/input was 1.15, dairy was 0.64 (cheese) to 0.94
(milk) and swine was 0.62.
They also compared the effects of different
animal feed inputs for provision of dry matter. Using Nova Scotia yields,
barley corn, corn silage, soybeans, hay, haylage and pasture were stacked
up against a purchased and delivered feed concentrate.
No surprise that the energy inputs for
pasture were lowest, at 14-26 Mcal per tonne (range is based on yield variations),
and that the feed concentrate were highest at 1,343 Mcal per tonne.
In the middle were corn at 10382478, barley
at 699-1004, soybeans at 489-1096, corn silage at 401 -512, haylage at
232-363 and hay at 190297.