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20th Int. Symp. “Animal Science Days”, Kranjska gora, Slovenia, Sept. 19th−21st, 2012.
Acta argiculturae Slovenica, Supplement 3, 9–15, Ljubljana 2012
Invited lecture
COBISS: 1.06
Agris category code: L01
LIVESTOCK PRODUCTION AS A TECHNOLOGICAL AND
SOCIAL CHALLENGE EMPHASIS ON SUSTAINABILITY
AND PRECISION NUTRITION
Csaba SZABÓ 1, Veronika HALAS 1
1 Kaposvár Univ., Guba Sándor út 40, 7400 Kaposvár, Hungary
ABSTRACT
Feeding the world’s growing population is one of the biggest challenges in the 21st century. As our natural resources
are depleting and our nature changing due to the human activity – sustainability is an emerging issue. In short sustain-
able agriculture means a system which preserves the basis of life of future generations. In the case of animal production
this includes the following key areas: providing sustainable feed base, reducing environmental impact, feed and food
safety and sustainable intensication. Animal production systems can be intensied throughout the application of preci-
sion livestock farming (PLF) systems. As the majority of production expenses related to feed, precision nutrition is a key
component in PLF systems. Precision nutrition includes the following principles: use of precise nutrient requirement
matrix, use of precise ingredient matrix, proper use of modiers and feed processing technologies and adjustment of
nutrient supply to match requirements of livestock. e aim of this paper is to highlight the current standing and future
perspectives of sustainable animal production and precision nutrition.
Key words: animal production / sustainability / precision nutrition
1 INTRODUCTION
Animal agriculture is facing a huge challenge in the
21st century. e world’s population is estimated to reach
10 billion by the end of the century. However, not only
the rise of the population, but also the improving living
standards in fast developing countries like China and In-
dia increases the demand of food. e average increment
rate of animal production is 1.6%/year (FAO, 2010) and
by 2016 the demand for animal feed will be increased by
more than 50% compared to 2006 (Farrell, 2009). Never-
theless, animal production also threatens our life on the
Earth. We are competing for food and the excretion of ni-
trogen, phosphorous and methane contributes to damag-
ing our nature. erefore, sustainability is a key question
in future animal production system.
In agriculture the rst green revolution lasted be-
tween 1930–1970 aiming the revolutionary improve-
ment of productivity (capacity and eciency). Nowadays
many speak about the second green revolution. However
it has a dierent meaning depending on which country
is considered. For countries with less developed agri-
culture it means improvement of yield and technology,
while for countries with developed agricultural produc-
tion it aims to achieve sustainable production. Sustain-
ability can be termed dierently and it has many aspects.
At the Earth summit in 1992 the UN Food and Agricul-
ture Organization (FAO) dened sustainable agriculture
and rural development as follows: “Sustainable develop-
ment is the management and conservation of the natural
resource base and the orientation of technological and
institutional change in such a manner as to ensure the at-
tainment and continued satisfaction of human needs for
present and future generations.” Such sustainable devel-
opment conserves land, water, plant and animal genetic
resources, is environmentally non-degrading, technically
appropriate, economically viable and socially acceptable.
As the demand for food is increasing and the area of ar-
able land decreases we continuously have to improve the
Acta agriculturae Slovenica, Supplement 3 – 2012
10
C. SZABÓ and V. HALAS
eciency of animal production. For that purpose one of
the possibilities is applying precision livestock farming.
erefore the aim of our paper is to highlight the
current standing and future perspectives of sustainable
animal production and precision nutrition.
2 SUSTAINABLE ANIMAL PRODUCTION
When we are talking about the sustainability of ani-
mal production in terms of preserving the basis of life
for future generations the following key areas have to be
considered:
–– providing sustainable feed base
–– reducing environmental impact
–– feed and food safety
–– sustainable intensication
2.1 PROVIDING SUSTAINABLE FEED BASE
Some news reported last summer that for the rst
time in history the US ethanol industry used more corn
than consumed by animals. is clearly shows the situ-
ation that how big is the competition for feed materials
which also suitable for both human consumption and
industrial utilization. Aer industrial processing of the
feedstus, usually a feedable by-product formed. Produc-
ers usually term these by-products as co-product and this
slight dierence reects in the pricing. While in the past
by-products were associated with low prices and were
a means to reduce feed costs, nowadays their prices are
tending to be similar to grains or even higher. However
their nutritional value is usually lower (mainly due to the
higher bre and lower energy content) and the properties
are dierent compared to the original raw material. Also,
about 30–40% is “lost” in amount of available feed base
compared to the weight of the raw materials. erefore
intensive research is needed to reveal all aspects of the
ecient use of these co-products.
Due to the foreseen increased demand for com-
pound feed we will face with shortage in protein sources
as well. Due to the overshing, the supply of shmeal
as the primary protein source of aquaculture industry
is already questionable. However, there is a huge feed
and food-production potential in the aquatic cultures.
Various algae are considered to be seaweeds, but these
plants contain high level of oil, which makes them a
good raw material for biofuel production. e remaining
co product or even the whole algae meal can be a good
feed source for ruminants, monogastric species and sh
and therefore intensive research is carried out (Carillo et
al., 2012; Angell et al., 2012; Toral et al., 2012). Fraser
omson representative of the McKinsey Global institute
told at the AquaVision 2012 (Stavanger) conference, that
aquaculture can potentially increase to meet the protein
needs of 500 million more people. To achieve that we
certainly have to change our eating habit as well. e im-
proved utilization of sea water aquaculture will preserve
our freshwater reserves.
e meat and bone meal had been banned from
the diets of farm animals due to the bovine spongiform
encephalopathy (BSE) disease. is caused less available
protein feedstus, and an increased production cost.
Unfortunately, the decision makers did not make dis-
tinction between the dierent products, as the conven-
tionally treated (solvent defatted, autoclaved and dried)
meal did not cause any proven BSE case. Nowadays the
EU is reconsidering to allow the cross species usage of
meat and bone meal. In that case we could have a dietary
2.5–3 percent good and price competitive alternative to
soybean meal.
A new possible future protein source is the earth-
worm (Ebadi, 2009) and insects. e advantage is that
agricultural and food wastes which cannot be used di-
rectly as feedstus can be turned into a valuable protein
source. e major obstacle is the legislation and scaling
up production to provide a competitive feed component.
ese were only examples of possible contributors
to have sustainable feed resources. ere is certainly
more opportunity we just have to walk with open eye and
be receptive to new ideas.
2.2 REDUCING ENVIRONMENTAL IMPACTS
Manure disposal is a major problem in highly inten-
sive farm animal production areas because of water and
air pollution. Among farm animals the monogastric spe-
cies excrete most of the nitrogen and phosphorus, due to
the digestibility properties, protein and amino acid sup-
ply and improper manure handling. For instance sows,
weaners and slaughter pigs excrete approximately 75%,
45% and 70% of the nitrogen, and 75%, 40% and 60%
of the phosphorus consumed, respectively. In the case of
Hungary about 34000 tons of N and 8000 tons of P can
potentially pollute the environment yearly from the pig
and poultry sector. is is about 5.0 kg of N and 1.1 kg
of P per ha of arable land. ese values are far below the
legislation in France, Denmark and e Netherlands
(Jongbloed et al., 1999). However, by improper manure
and slurry handling the regional emission can be higher.
Using dietary nutrient recommendations based on ileal
digestible amino acids, ideal protein concept and digest-
ible phosphorus can result about 20–30 percentage re-
duction in N and P excretion. Shiing recommendation
Acta agriculturae Slovenica, Supplement 3 – 2012 11
LIVESTOCK PRODUCTION AS A TECHNOLOGICAL AND SOCIAL CHALLENGE EMPHASIS ... AND PRECISION NUTRITION
from total P to digestible P will not reduce signicantly
the P emission in countries where the P emission per ha
is quite low and legislation is not foreseen. e dietary
inclusion of microbial phytase depends on economic
considerations. We should not forgot, that the manure is
a valuable natural fertilizer to the soil. It degrades gradu-
ally down in 4–5 years and provides not only the major
elements to the plants, but the trace elements as well. e
problem is that farms are specializing more and more,
and the animal production is separated from plant pro-
duction. us, the utilization of the manure as a valuable
co-product is not solved in many places. More integrated
agricultural systems or better co-operations with special-
ized farms (plant/crop and animal producers) has to be
in order to use the resources eciently and thus to re-
duce the ecological footprint of agriculture.
2.3 FEED AND FOOD SAFETY
During the past years we have experienced several
food and feed safety scandals. By the continuous im-
provement of the eld to fork chain traceability, these
problems can be treated quite in time in Europe. Never-
theless, we are importing signicant amount of feedstu
and food from third parties with less developed feed and
food safety systems. Due to the globalisation where even
a simple carrot travels thousands of kilometres from the
producer to the consumer this can be a real source of
danger.
However, the hottest issue nowadays is the usage of
genetically modied organisms. ese plants and ani-
mals oer advantages to the producer: tolerance to her-
bicides in order to improve the eciency of weed control,
protection against the damage of insects to save soil ferti-
lization cost, improve the phosphorous digestibility, etc.
At rst sight these organisms has no adverse eect on nu-
tritive value, animal performance or human health. ey
might not have; however, we need some caution based on
earlier experiences with excellent solutions. Let’s cite the
story of antibiotics. Concerns about antibiotic resistance,
especially associated with antibiotics that were used both
in human patients and as growth promoters in livestock,
led to the Swann Report (Swann et al., 1969). In the re-
port it was recommended that antibiotics used in human
medicine should not be used as growth promoters. It is
believed that by separating the human and animal anti-
biotics we will solve the problem of transborder resist-
ance. But in about thirty years we have learned a new
term – cross resistance. ere is even a concern, that an-
tibacterial agents used in households, food industry and
in hospitals may play a role in the emergence of bacteria
resistant to antibiotics. So what can we learnt from that?
Not everything is gold that shines. Last year a Bt-corn-
eld (insecticide sweet corn) was completely damaged in
the USA by the western corn rootworm which gets ac-
customed to the poison in the plant. Ermakova (2005)
reported reduced growth of rat’s ospring and more than
50% mortality among pups which mother fed GM soy-
bean based diet. Earlier Ewen and Pusztai (1999) dem-
onstrated reduced growth and damaged immune system
of rats fed GM potatoes. Domingo (2000) summarized
our knowledge in the eld of GM safety: many opinions,
but few data. Despite these and other cautionary results
still insucient attention is paid to this potential danger.
erefore it is needful to carry out long term studies and
have experiences on using GM products as animal feed-
ing and GM products have to be considered as not the
only one solution on the feed and food source problem.
2.4 SUSTAINABLE INTENSIFICATION
To full the world’s increasing demand of food we
have to intensify the production systems. is does not
mean that there is no room for extensive production,
but extensive systems require more land and we have
limitations in that. Our resources have to be utilized on a
proper way; therefore a further intensication of the con-
centrated farms is necessary. By concentration of animal
farms and the advances in technology farmer can have
such amount of information, which cannot be handled
manually. is needs a special information intensive
management system so called precision livestock farm-
ing. Precision livestock farming is an integrated approach
of animal production aiming to improve the eciency
of use of resources, as well as to enhance animal health
and welfare, and thus contributes to sustainable animal
production systems. It adopts research and development
focusing on technological innovations based on increas-
ingly specialized tools that go beyond human mind pow-
er, and are related to the acquisition, access, and process-
ing of the huge number of data (Mollo et al., 2009).
3 PRECISION NUTRITION
A prerequisite for precision livestock farming is to
feed the animals in a way that precisely full their nutri-
ent requirement. Considering that 60–70% of the total
cost of production attributes to feeding cost therefore the
nutrient supply is the most critical element of economic
animal farming. Precision livestock farming requires
precision nutrition that is by denition an “information
intensive nutrition”, the actual nutrient supply is adjusted
to the real-time data on the animal and its production
Acta agriculturae Slovenica, Supplement 3 – 2012
12
C. SZABÓ and V. HALAS
level. It means not only oering proportional feed rations
but supplying continuously changed “tailor made” diets
for individual animals. For that reason the animals has
to be identied and feed individually according to their
actual requirement. But how can be precision nutrition
achieved in practice?
According to Sifri (1997) and Pomar et al. (2009)
the principals of precision nutrition are the followings:
–– Use of precise nutrient requirement matrix
–– Use of precise ingredient matrix
–– Proper use of modiers and feed processing tech-
nologies
–– Adjustment of nutrient supply to match require-
ments of livestock
3.1 USE OF PRECISE NUTRIENT REQUIREMENT
MATRIX
It is well known that the actual nutrient require-
ment depends on animal factors (production level, ge-
netic potential, gender, age and body weight, and health
status), environmental factors (ambient temperature and
humidity, space allowance, number of stress factors, etc.),
as well as on nutritional factors (nutrient composition
and ratios, digestibility of nutrients, and level of anti-
nutritive factors). e nutrient requirement can be well
established/estimated with mathematical models. An
example is given in Fig. 1 showing how digestible lysine
requirement of pigs with dierent genotype changes dur-
ing the growing and fattening period (adopted from van
Milgen et al., 2008). e simulated genotypes have the
same average daily gain (762 g/d) and daily feed intake
(2.24 kg/d); however, the growth curves of them dier
gaining 758 vs. 766 g/d in growing (30–65 kg) and 812
vs. 700 g/d in fattening period (65–115 kg), respectively.
e digestible lysine requirement certainly diers and
the genotypes have to be fed dierently according to the
dynamics of their growth otherwise the genetic potential
cannot be realized and likely the slaughter quality is de-
teriorated. e advantage of using such models instead
of table values is that the model can predict the nutri-
ent requirement at any time point and not only in certain
time period and thus the number of phases used during
the pig production is a professional decision supported
by well predicted data.
In order to be able to adjust the daily nutrition to
the actual requirement of livestock the animals has to
be checked by real-time body weight control. e body
weight can be determined daily by a weighing adapter
or by body shape analyser (Banhazi et al., 2009). All the
factors that inuence production and therefore nutrient
requirement should be controlled. In precision livestock
farming the technology and housing conditions are op-
timized, however, if it is needed the nutrient supply can
also be adjusted according to the changed environmen-
tal factors. e health and wellbeing control (behaviour
and sound analysis, collecting physiological parameters
like deep body temperature, respiratory rates) is also very
useful; in case of conrming any disorder the problem
can be xed immediately.
3.2 USE OF PRECISE INGREDIENT MATRIX
e principal of precise formulation is to be able to
evaluate properly the nutritional potential of the com-
pound feed. e progression of the characterization of
Figure 1: Simulated digestible lysine requirements for two pigs having same average daily gain and feed intake but dierent shapes of
growth curve (van Milgen et al., 2008)
Acta agriculturae Slovenica, Supplement 3 – 2012 13
LIVESTOCK PRODUCTION AS A TECHNOLOGICAL AND SOCIAL CHALLENGE EMPHASIS ... AND PRECISION NUTRITION
nutritional potential of feedstus and animal require-
ments from a total to a digestible basis, and then to an
available or net basis, allows for the formulation of di-
ets with nutrient levels that are closer to the animals’ re-
quirements without the use of excessive safety margins
(Pomar et al., 2009). It is worth by theory, but protein
and even the energy evaluation are dierent in dierent
countries. In pigs for instance the net energy is the most
reliable energy evaluation system particularly if bre rich
feedstus – like dierent by-products – are used in diet
formulation. However, there are only a few countries
using net energy system in practical swine feeding. e
protein evaluation in monogastrics feeding should be
based on amino acid content of ingredients with consid-
eration on the ileal digestibility. For the sake of precise
diet formulation dietary ileal digestible amino acid con-
tent should be expressed in standardized or true digest-
ibility (SID or TID, respectively) rather than apparent
digestibility (AID) bases, considering that unlike appar-
ent values both SID and TID content of feedstus are
additive (Stein et al., 2007). Table values for net energy
and dietary SID, TID amino acid of dierent feedstus
are available; however, due to the fact that the nutrient
content is determined by several conditions (soil, pre-
cipitation, cultivation, etc.) there might be big variance
in nutrient content of feedstus originated from dierent
region or batches. erefore for precision nutrition na-
tional dataset or rather reliable prediction equations are
required to be able to determine the bioavailability of en-
ergy and amino acids of feedstus and compound feeds.
In practice the feeds are usually overformulated by
even 7.5% to ensure that no more than 20% of the batches
of feed produced are nutritionally inadequate (van Kem-
pen and Simmins, 1997). e safety of margin can be re-
duced if reliable and actual chemical composition is used
in diet formulation. By using prompt assay such as near
infrared reectance spectroscopy (NIRS) the diet formu-
lation is adjusted according to real-time analysis of the
feed ingredients to reduce variation in nutrient delivery
to the livestock. In addition to determination chemical
composition modern scanning NIR spectrophotometers
and associated analysis soware present the potential for
simultaneous prediction of available energy and amino
acids in feed ingredients for all livestock (van Barneveld,
2003). In this way the overformulation can be reduced to
zero that is desirable from both economic and environ-
mental point of view.
3.3 PROPER USE OF MODIFIERS AND FEED PRO
CESSING TECHNOLOGIES
Dierent feed additives are used in compound feed
production for purposes of improving the quality and
storage life of feed, to improve the animals’ perform-
ance and health. Feed processing technologies are usu-
ally aiming to increase the bioavailability, particularly the
digestibility of dietary nutrients and energy. erefore
use of modiers and processing technologies improve
the nutritive value of the compound feed that has to be
considered in precision feeding. Fig. 1 shows how the
proper/optimal protein supply changes with increasing
bioavailability (digestibility and/or availability) of amino
acids. According to the linear-plateau concept the rela-
tionship between the protein intake and protein deposi-
tion is described by a two-phase-graph being composed
Figure 2: Example of level of incorporation of the initial (A) and nal (B) premixes or feeds in blend feeding systems (Feddes et al., 2000)
Acta agriculturae Slovenica, Supplement 3 – 2012
14
C. SZABÓ and V. HALAS
of a regression line and a constant phase. e optimal
dietary protein intake is at the point when the function
reaches rst its maximum value (A, B, C). However, exact
in ection point depends on the slope of the regression
line phase that is certainly determined by the bioavail-
ability of amino acids. e impact of the modi ers there-
fore should be quantify in order to evaluate precisely the
nutritional potential of feed ingredients and thus to avoid
overformulation of the diets.
3.4 ADJUSTMENT OF NUTRIENT SUPPLY TO
MATCH REQUIREMENTS OF LIVESTOCK
Due to individual variance the nutrient supply that
is ful l the requirement of the maximal growth of a herd
is not exactly the optimum for each individual animal
within the herd. Hauschild et al. (2010) showed that sup-
plying a feed with Lys:NE ratio according to the arith-
metic mean of the requirement of pigs is insu cient for
the maximal growth of the herd. e growth response
reached its maximum when 82% of the animals were fed
above their requirement. Actually the di erences in indi-
vidual nutrient requirement increase with the degree of
heterogeneity of the population, which is determined by
genetic, environmental or management factors (Pomar et
al., 2003). Feeding pigs individually according to genet-
ics, gender and actual feed intake and growth patterns
can help to simplify the estimation of nutrient require-
ments (Pomar et al., 2009). In this way the homogeneity
of the herd is de nitely be under the level of group-fed
livestock.
Special individual feeders are available (Feddes et
al., 2000; Bánházi et al., 2009, Pomar et al., 2009) driven
by computerized data process to provide a “tailor made”
diet for each animals. e intelligent system use di erent
pre-mixed feeds to adjust the nutrient supply to the ac-
tually fed animal. Considering that the optimal nutrient
concentration related to dietary energy content progres-
sively decrease (NRC, 1998) the feeds have to be mixed
with a non-linear algorithms (Fig. 2).
Such a system allows a daily adjusted feeding pat-
tern for individual animal, therefore the oversupply at-
tributed to phase feeding can be avoided. In this way the
excess nutrients are reduced to zero and the e ciency of
production is maximal (Pomar et al., 2011). Fig. 3 repre-
sents the integrated management system for pig produc-
tion in which all the data are collected by the computer
and processed with a Decision Making System. e sug-
gested system integration approach would also mean that
where it is possible the utilization of existing hardware
and so ware components/products need to be consid-
ered. If system components are independently developed
and the components compete with existing products; it
is likely that precision nutrition and livestock farming
(PN&LF) developments and implementation on farms
will fail (Bánházi et al., 2009).
Determining and o ering the optimal nutrient sup-
ply for individual animals at any circumstances is very
complex in practice. Companies and research groups all
over the word are involved with developing commer-
cially sound PN&LF components; however, a few groups
have attempted to combine these components into one
system, because of the technical/operational di cul-
ties involved. Nonetheless, business opportunities for a
PN&LF package development (including the provision of
complete systems, expert advice, training, backup analy-
sis and general support) do exist, but very few companies
have taken advantage of such opportunities (Bánházi et
al., 2009).
Figure 3: Schematic representation of an integrated system in pig production (Banhazi et al., 2009)
Acta agriculturae Slovenica, Supplement 3 – 2012 15
LIVESTOCK PRODUCTION AS A TECHNOLOGICAL AND SOCIAL CHALLENGE EMPHASIS ... AND PRECISION NUTRITION
4 CONCLUSIONS
It is likely that sustainable intensication of agricul-
tural production will be one of the key issues in the com-
ing years. However, if we could make rm conclusions
regarding to the future, it would presume that we have
a time machine. Instead of that we can phrase a wish:
be the force with us, to give right answers in time to the
challenges we are facing with.
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