Agriculture Reference
In-Depth Information
All the pigs in each trial were kept in the
same pen but fed individually as described
in previous experiments. Feeding phases
lasted for 28 days for a total experimental
length of 84 days. Pigs were weighed weekly
in both trials and their DXA body compos-
ition measured at the beginning of each
feeding phase and at the end of the trials.
Feed costs were calculated using recent
feed ingredient prices of Quebec, Canada.
Feeding pigs individually with daily
tailored diets (MPI) in the first validation
trial (AIPF I
,
Table 12.1
)
did not affect ADG,
FCR, APD or final BW in relation to the two
other tailored treatment groups (3P and
MPG). However, pigs fed with the COM
diets consumed less feed (
P
< 0.05) and had
lower FCR (
P
< 0.05) than the three other
treatment groups, which may be related to
the variation in nutrient and ingredient
compositions of the diets. Interactions (
P
<
0.05) between period and treatment effects
were found for ADFI, ADG and FCR. These
interactions resulted from the performance
differences observed between COM and the
other experimental groups.
The sex by treatment interaction was
not significant for any of the variables stud-
ied in the second validation trial (AIPF II,
Table 12.2
)
and therefore, only the across-
sex pooled values are presented in this
chapter. In this trial, ADFI and FCR were not
affected by treatments. Feeding pigs based
on a daily basis programme considering
110% or 100% of the estimated individual
nutrient requirements also did not influence
ADG, APD and final BW in relation to ani-
mals in the 3P feeding programme. Pigs fed
MPI90 showed intermediate results between
MPI100 and MPI80. The model used to esti-
mate individual Lys requirements seems to
be properly calibrated since feeding pigs
at 80% Lys requirements decreased (
P
< 0.05)
ADG and APD in relation to MPI100 and
3P pigs.
Accounting for the variation among
animals in nutritional requirements may be
an important tool to control the heterogen-
eity of performance data. In the second val-
idation trial, animals fed MPI100 diets
showed a lower degree of dispersion com-
pared to the 3P treatment in ADFI (CV of
14.5% in the MP100 group and 17.7% in
the 3P group), ADG (7.1% and 9.1%), APD
(6.0% and 8.4%) and final BW results (5.1%
and 8.1%). Although the homogeneity
within the populations is not frequently re-
ported, this positive effect of precision feed-
ing on animal homogeneity may be an im-
portant advantage in industrial scenarios.
In the first validation trial, average SID
Lys concentrations in 3P diets were 1.05%,
0.73% and 0.64% during feeding phases
1
to
3,
respectively
(Fig. 12.4
)
. The SID Lys
concentration given during the first week
of each feeding phase may slightly differ
Table 12.1.
Performance of pigs fed according to a three-phase feeding programme (3P) obtained by
blending fixed proportions of diets A and B, a commercial three-phase feeding programme (COM) or two
daily-phase feeding programmes in which the blending proportions of diets A and B were estimated daily to
match the lysine requirements of the group (MPG) or of each individual pig (MPI) (trial AIPF I)
1
.
Treatments
3P
COM
MPG
MPI
SEM
P
value
2
ADFI,
3
kg/day
3.05
a
2.73
b
3.07
a
3.05
a
0.043
0.0025
ADG, kg/day
1.11
1.07
1.11
1.10
0.011
0.5805
FCR, kg/kg
2.76
a
2.58
b
2.81
a
2.78
a
0.035
0.0095
APD, g/day
161
155
155
154
0.210
0.6492
Final BW, kg
134
131
135
136
1.170
0.2422
1
Least square means obtained from a repeated measures analysis; ADFI: average daily feed intake; ADG: average daily gain;
FCR: feed conversion ratio; APD: average daily protein deposition; BW: body weight.
2
Effects of treatment, period and interaction were considered in the analysis. Period was significant (
P
< 0.01) for all
variables. Interaction period × treatment was significant for ADFI (
P
< 0.01), ADG (
P
< 0.01) and FCR (
P
< 0.05).
3
Means within lines followed by different letters are significantly different
(P
< 0.05).
a
and
b
indicate significant statistical differences among means within rows.
