Agriculture Reference
In-Depth Information
3.0
2.5
2.0
1.5
1.0
0.5
2,000
4,000
Milk production (kg FPCM
per cow per year)
6,000
8,000
10,000
Fig. 2.6. Relationship between milk production level (kg fat and protein corrected milk (FPCM) per cow
per year) and total greenhouse gas emissions (GHG; expressed in kg of CO 2 equivalents per kg fat and
protein corrected milk, FPCM). Prediction equations based on a database containing 155 countries
described by Gerber et al . (2011). Solid line: GHG=1.373552×exp[2.3837×(0.999332 FPCM )]; dashed line:
GHG=3315.5/FPCM+0.8649.
predicts a somewhat more pronounced decline
(2.47 and 1.25 kg CO 2 -e kg −1 FPCM, respec-
tively). For the dairy production system in the
Netherlands (Fig. 2.5), the non-linear equation
would predict just a 2% decline in GHG emission
(from 1.42 down to 1.39 kg CO 2 -e kg −1 FPCM in
1990 and 2009, respectively), whereas the linear
equation predicts a 10% decline (from 1.39 to
1.25 kg CO 2 -e kg −1 FPCM in 1990 and 2009,
respectively). However, the reduction in CH 4
per kg FPCM in the Dutch dairy system is in
itself already 0.06 kg CO 2 -e kg −1 FPCM. Since the
N content of the diet was reduced from 1990 to
2009, and given that FCE improved by more than
10%, which will also decrease the emissions of
N 2 O and CO 2 , the estimate of the non-linear equa-
tion understates the reduction in GHG emission
upon increased production levels under the
Dutch system. Clearly, the analysis based on
between-country data should not be used for within-
country calculations of productivity increases.
land significantly, food production must inten-
sify to ensure an affordable, abundant food
supply. In particular, the ability of ruminants
to turn human-inedible products into human-
edible products will become increasingly
important in terms of global food security.
Increases in ruminant production will largely
have to come from further advancement in the
efficiency of livestock systems in converting
natural resources into human-edible food.
Intensive production systems are a source of
concern due to environmental impacts includ-
ing N pollution and GHG emissions. Past
improvements demonstrate the ability of pro-
duction efficiency to decrease the environ-
mental impact per unit of milk, particularly
that of enteric CH 4 emissions. Improvements
in feed digestibility and better post-absorptive
matching of absorbed nutrients with produc-
tion level must be achieved, whilst at the same
time not increasing the human-edible inputs
per unit livestock product. In improving the
efficiency of nutrient use for milk and beef
production by cattle, and their environmental
impact, it is imperative that the wider animal
health and welfare, social and economic impli-
cations of policies to increase productivity are
considered.
Conclusions
Major gains in efficiency of ruminant produc-
tion systems are needed. With no prospects to
increase the amount of arable agricultural
 
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