Agriculture Reference
In-Depth Information
Table 5.8 . Proposal to assess the effects of inhibitors of nutrient availability (e.g. phytate).
Groups
Diet composition
Measurements
1
Balanced diet including typical levels of isogenic
parenteral line fed ad libitum
Depends on claim of genetic
modifi cation:
 feed intake
 animal performance, feed and
nutrient (e.g. P) effi ciency
 digestibility of inhibited nutrient
 concentration of inhibited nutrient
in indicator organs/tissues
2
Balanced diet including typical levels of transgenic
line adequate to Group 1 (e.g. low phytate crop)
fed ad libitum
3
Diet of Group 1 and supplemented with inhibited
nutrient (e.g. phosphorus) fed in adequate amounts
to Group 2
4
Inclusion of further groups with other commercial
varieties (unsupplemented and supplemented with
inhibited nutrient)
to assess GM crops with output traits are
given for poultry meat production, egg
production, pigs, lactating ruminants, grow-
ing and i nishing ruminants and aquaculture.
Furthermore, ei ciency studies with
second-generation GM plants may also be
used or combined with studies to measure
the digestibility/bioavailability of the newly
expressed substances. Changed composition
of GM plants and derived feed may also
inl uence the composition of food of animal
origin, as has been demonstrated exemplarily
for soybeans with a modii ed fatty acid
pattern (for more details, see Chapter 10).
long-term ef ects were assessed as being
negligible. In general, a methodical improve-
ment of the risk assessment procedure has
been recommended, including a higher
number of replications and additional
control groups to demonstrate the biological
range of measured parameters.
In addition to long-term feeding studies,
multi-generation studies (mostly i ve
generations; see Flachowsky et al ., 2005b;
Snell et al ., 2012) should be carried out to
test the inl uence of GM feed on repro-
duction, long-term health and metabolic
ef ects in laboratory and target animals.
More details about long-term and multi-
generation feeding studies are described in
Chapter 8.
5.5.4 Long-term and multi-generation
feeding studies
5.6 Conclusions
Long-term feeding studies cover the whole
lifespan, or a very long period of this, of the
animals, for example, in the case of laying
hens or dairy cows (see Table 5.3 and
Chapter 8). Apart from the animals'
performance, the answers expected from
such studies include their fertility and health
when fed with high amounts of GM feed.
Can animal feeding trials contribute to the
assessment of long-term ef ects? h is was
the main question of the BEETLE study
(BEETLE, 2009). h e assessment of the data
and results from the online survey of
BEETLE (2009) on animal health did not
show any new aspects. Some participants of
the online survey expected only potential
long-term ef ects in relation to allergenicity
in humans, but all other possible adverse
h e objective of animal feeding studies ( in
vivo studies) is to characterize the ef ects of
specii c feeds in animals. Feeding studies
start with the compositional analysis and in
silico and/or in vitro measurements.
Feeding studies can be done with
laboratory and target animals. Laboratory
animals are used for testing single substances
and toxicological parameters in animals.
h e measuring of digestibility/availability
of nutrients, long-term feeding studies and
multi-generation studies are done with
laboratory and target animals. Tolerance
studies to measure the optimal dosage of
specii c feed in animal diets, ei ciency
experiments and the inl uence of feeds on
 
 
 
 
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