Agriculture Reference
In-Depth Information
enterprise more efficient and profitable. In
fact, there is no defensible way of predicting
the response of growing animals to nutri-
ents, or of optimizing the feeding of broilers,
other than by the use of simulation models
that can accurately predict food intake.
process margin is to be assessed for nutritional
decisions. For example, if nutrition is opti-
mized for margin at the farm gate, with live
bird weight (and perhaps downgrading) af-
fecting revenue, then nutritional responses in
growth, feed conversion ratio and mortality
will need to be considered. If, however, mar-
gin is measured after the production of pro-
cessed portions or meat, then nutritional
responses in these characteristics, as well as
those operating at the farm gate, will affect the
outcome. These are real differences which
lead to different nutritional decisions (Fisher,
2008). All decisions, therefore, whether these
apply to the choice of the genotype to be used,
the instantaneous environmental condi-
tions that should be applied throughout the
growing period (Timmons and Gates, 2003)
or the nutrient composition of feeds to be
offered, should be made as far as possible in
terms of the objectives of the business.
Using the results of a balanced protein
response trial, Fisher (2008) calculated the
revenue derived from selling broilers at the
farm gate, processed, or further processed,
making use of the measured food intakes,
growth rates and yield of parts of male and
female broilers of two different strains fed a
range of balanced dietary protein levels. He
then compared the profit derived from these
sales taking account of the cost of ingredi-
ents in the UK in 2006 and demonstrated
that using a fixed (recommended) protein
level under all circumstances resulted in
considerable loss of potential profitability.
The loss of margin when using a fixed level
of protein as opposed to that which yielded
the highest margin is shown for two revenue
categories in
Table 13.2
.
Broiler producers
'Nutrient Requirements' vs Optimization
Fisher (2008) reasoned that the predomin-
ant model used in poultry nutrition, the
idea of a 'nutrient requirement', which is
seen as a characteristic of the broiler and is
the nutrient level required to support 'max-
imum' or 'optimum' production levels, is
outdated and needs to be replaced with one
in which nutritional decisions are made
entirely in terms of the objectives of the
business. With this approach, which ap-
plies systems thinking and modelling to the
problem of feed formulation, nutrient levels
are chosen that will maximize margin or
perhaps combine with some other business
objective. The 'needs' of the broiler in this
case are not considered when making deci-
sions about what nutrient levels to use. This
approach builds on the principle espoused
by the Reading Model (Fisher
et al
., 1973) in
which the optimum economic intake of
amino acids for laying hens becomes the
basis on which their feeds are formulated.
Feeding animals to achieve some commer-
cial objective(s) rather than feeding them
to meet a 'requirement' makes good business
sense, but requires a paradigm shift in the
attitude of nutritionists to feed formulation:
the nutrition of the broilers must be inte-
grated into the management of the business.
This shift in thinking raises at least two
interesting and important issues.
Because economic circumstances change
from time to time, the nutritional strategy
applied to maximize margins will also need
to change. As Fisher (2008) points out, these
strategies may or may not be compatible with
the other objectives of the business (e.g. satis-
fying market demands) but at least manage-
ment should know what options exist so that
the best overall strategy can be selected. Also,
and equally importantly, a choice must be
made about which stage in the production
Table 13.2.
Loss of margin (£/
100
birds) when using
the recommended dietary balanced protein level
rather than the level yielding the maximum
potential margin. (From Fisher, 2008.)
Loss of margin (£/
100
birds) at sale of:
Strain/sex
Live bird at farm
Processed bird
Ross 308 M
Nil
60.5
Ross 708 M
Nil
50.4
Ross 308 F
9.45
Nil
Ross 708 F
13.6
32.7
