Agriculture Reference
In-Depth Information
GM events that are relevant for feed use, has
been collected in various ways: Internet
searches; screening of the oi cial regulatory
information publicly available from the
major biotech companies; from queries on
the ISI Web of Science database for
publications in peer-reviewed journals using
the appropriate keywords; from reviewing
searches for relevant patents within the
worldwide collection of published appli-
publication authors' names following the
methodology of Parisi
et al
. (2013). Only the
events for which a proof of concept exists -
i.e. an article, a patent or a i eld trial - were
then included in a specii ed database where
the relevant information for this chapter
was gathered. Also, when one type of proof
of concept was found (for instance, a
publication regarding a specii c event), the
others were searched systematically (in this
case, corresponding i eld trials and patents).
h e purpose was to establish a typology of
events according to their advancement in
the research pipeline. All events were
classii ed depending on their proximity to
market, using i ve categories adapted from
Stein and Rodríguez Cerezo (2009):
Commercialized: when the event is
already marketed in at least one country.
Commercial pipeline: events that have
been authorized for cultivation in at
least one country but are not yet
marketed.
Regulatory pipeline: events in the
regulatory process for being marketed in
at least one country.
Advanced development: events for which
there are multiple-location i eld trials
and more than one proof of concept.
Early development: events for which
there is only one proof of concept.
Information on the existence of feed trials,
feeding trials or patents is displayed in
Tables 12.1-12.4 (see also Chapters 7 and
10). Altogether, about 110 events relevant
to animal nutrition have been identii ed; of
those, only two are already commercialized,
seven are in the commercial pipeline, a
couple are in the regulatory pipeline and
about one-quarter are in advanced
development. h e pipeline also coni rms the
dominant position of US research: about
half of the events are developed in this
country, while the second developer is the
EU-27, with 14 events, followed by China
(12) and Japan (10).
GM Crops for Animal Nutrition
phosphorus nutrition
Phytate - a salt form of phytic acid - is the
main storage form of phosphorus (P) in
plant seeds and represents the major source
of l ux of P into the environment: plants
take up P from the soil and transfer a
signii cant amount to seeds, where 75% of
the total P is stored in the phytate form
(Raboy, 2001). Altogether, the amount of P
that crops incorporate each year into phytate
is equivalent to nearly 65% of the quantity
of P in mineral fertilizer used worldwide
(Lott
et al
., 2000). However, phytate is
considered an anti-nutrient and an
undesirable component of feedstuf s for a
number of reasons:
1.
It is a strong chelator of mineral cations
such as iron, calcium, zinc or magnesium
and therefore prevents the use of these
essential minerals by humans and animals
eating the plants. It may also preclude the
availability of proteins by reacting with
them.
2.
h e digestibility of phytate is also very
poor and it constitutes a bad source of
inorganic and available P for non-ruminant
animals, including humans, since they lack
dephosphorylation enzymes.
3.
Hence, livestock such as poultry, swine
and i sh excrete large quantities of
undigested phytate that eventually
contribute to water pollution and generate
eutrophication.
4.
While the P content of their manure is
high, the feed of monogastric (i.e. non-
