Response of male BUT big 6 turkeys to varying amino acid feeding programs.

Abstract

Dietary protein is a major cost contributor in turkey nutrition. Therefore, a feeding trial with male BUT Big 6 turkeys to 154 d of age was conducted to examine how live performance and economics are affected when dietary amino acid levels are altered in different phases. Six dietary treatments were run with treatment 1 as the control in which balanced protein levels were according to recommendations during all 6 phases. Treatments 2 through 6 used combinations of balanced protein (based on lysine) that ranged from 90 to 120% of those used in treatment 1. The combinations for the 6 phases of feeding were 120, 120, 120, 120, 90, and 90% for treatment 2; 120, 120, 120, 100, 90, and 90% for treatment 3; 120, 120, 100, 100, 90, and 90% for treatment 4; 120, 120, 120, 120, 100, and 100% for treatment 5; and 90, 90, 90, 100, 100, and 100 for treatment 6. Final BW was highest in treatment 4 and lowest in treatment 2 (P < 0.05), whereas final BW were intermediate and statistically not different in treatments 1, 3, 5, and 6. Breast meat yield was highest in treatment 5 and lowest in treatments 2 and 3 (P < 0.05). Mortality seemed to be reduced in treatment 6 compared with treatments 2, 3, and 5 (P < 0.10). Performance data in combination with economic simulations suggested that the feeding regimens of treatments 4 or 6 might be alternative strategies to treatment 1 to improve overall profitability.

Full text

Page 1

Response of Male BUT Big 6 Turkeys to Varying
Amino Acid Feeding Programs
A. Lemme,*1U. Frackenpohl,† A. Petri,* and H. Meyer†
*Degussa AG, FA-M-AN, Rodenbacher Chaussee 4, 63457 Hanau, Germany;
and †Moorgut Kartzfehn von Kameke OHG, 26217 Bo ¨sel, Germany
ABSTRACT
in turkey nutrition. Therefore, a feeding trial with male
BUT Big 6 turkeys to 154 d of age was conducted to
examine how live performance and economics are af-
fectedwhendietaryaminoacidlevelsarealteredindiffer-
ent phases. Six dietary treatments were run with treat-
ment 1 as the control in which balanced protein levels
were according to recommendations during all 6 phases.
Treatments 2 through 6 used combinations of balanced
protein (based on lysine) that ranged from 90 to 120% of
those used in treatment 1. The combinations for the 6
phases of feeding were 120, 120, 120, 120, 90, and 90% for
treatment2;120,120,120,100,90,and90%fortreatment3;
Dietary protein is a major cost contributor
Key words: turkey, balanced protein, lysine, feeding regimen, economics
2006 Poultry Science 85:652–660
INTRODUCTION
In general, feed costs account for about two-thirds of
the overall cost in animal production. Therefore, min-
imizing feed cost is a major goal also in turkey produc-
tion in which male birds achieve BW of greater than 20
kg over more than 20 wk (Nixey, 2002), and consume
more than 50 kg of feed. In turkey production, phase
feeding is well established and 6 phases are often used
for male birds although recommendations vary (NRC,
1994; GfE, 2004; BUT, 2005; Hybrid, 2005; Nicholas,
2005). However, phase feeding programs with more
phases have been established by some turkey growers.
In Europe, phases 1 and 2 last 2 and 3 wk; all subsequent
phases last 4 wk each. Therefore, it is possible to adjust
the nutrient and energy contents of the feeds according
to the birds’ requirements for their respective age or
BW. Typically, dietary energy increases in subsequent
phases whereas amino acid concentrations decrease
(NRC, 1994; GfE, 2004; B.U.T, 2005; Hybrid, 2005; Nicho-
las, 2005). Both energy and amino acids are major cost
contributors to the diets and should thus be supplied as
2006 Poultry Science Association, Inc.
Received July 22, 2005.
Accepted December 3, 2005.
1Corresponding author: andreas.lemme@degussa.com
652
120, 120, 100, 100, 90, and 90% for treatment 4; 120, 120,
120, 120, 100, and 100% for treatment 5; and 90, 90, 90,
100, 100, and 100 for treatment 6. Final BW was highest
in treatment 4 and lowest in treatment 2 (P < 0.05),
whereas final BW were intermediate and statistically not
different in treatments 1, 3, 5, and 6. Breast meat yield
was highest in treatment 5 and lowest in treatments 2 and
3(P<0.05).Mortalityseemedtobereducedintreatment6
compared with treatments 2, 3, and 5 (P < 0.10). Perfor-
mance data in combination with economic simulations
suggested that the feeding regimens of treatments 4 or 6
might be alternative strategies to treatment 1 to improve
overall profitability.
much as necessary but as little as possible to optimize
feed cost and efficiency of use of the nutrients and
energy.
In a previous turkey feeding trial, dietary protein lev-
els could be reduced by 10% with no significant effects
on performance when all essential amino acids were
balanced and kept at a recommended level (Lemme et
al., 2004). The protein reductions were applied from
phase 2 to phase 6. However, simulating current practi-
cal conditions in which crystalline amino acids such as
L-Arg, L-Val, L-Ile, and L-Leu are not registered and thus
not available for turkey feeding in Europe and North
America, a 10% CP reduction resulted in impaired ani-
mal performance most likely due to limiting effects by
Arg, Val, Ile, or Leu (Lemme et al., 2004). Data by Wal-
droup et al. (2003) generated with 16- to 20-wk-old tur-
keysalsosuggestedthatagradualdecreaseofdietaryCP
with balancing only Lys, Met + Cys, and Thr gradually
impaired performance. That Ile and Val are important
for maintaining the performance level when feeding low
protein diets was demonstrated by Waibel et al.
(2000a,b). Again, under current commercial conditions
with only Lys, Met, Thr, and Trp available in crystalline
form, it is hardly possible to formulate low protein diets
matching optimum Arg, Val, Ile, and Leu levels. There-
fore, alternative strategies in terms of amino acid supply
should be developed.

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AMINO ACID FEEDING PROGRAMS IN TURKEYS
653
Table 1. Feeding regimens (as % of recommended amino acid supply)1,2
Treatment
Phase123456
I
II
III
IV
V
VI
Replicates
Birds/replicate
Birds/treatment
100
100
100
100
100
100
120
120
120
120
90
90
120
120
120
100
90
90
120
120
100
100
90
90
120
120
120
120
100
100
90
90
90
100
100
100
444444
77
308
77
308
77
308
77
308
77
308
77
308
1Recommendations refer to the control diets used in the trial by Lemme et al. (2004) and comprised dietary
Lys, Met + Cys, Thr, Trp, Arg, Val, Ile, and Leu. Diet compositions are shown in Table 2.
2Feeding regimens: 100: typical amino acid profiles with typical dietary protein levels (Lemme et al., 2004);
120: whole amino acid profiles were increased by 20%; 90: whole amino profiles were decreased by 10%.
Wijtten et al. (2004b) reported an experiment in which
entire amino acid profiles in broiler diets were varied
such that the protein content was altered, but the ratios
between the amino acids were kept constant. The au-
thorsdemonstratedthatfeedingincreasedbalancedpro-
tein levels particularly in the starter phase had positive
effects on the overall growth development of broilers.
Data of the same study suggested that it might be possi-
ble to reduce the balanced protein level in the finisher
phase without affecting broiler performance if amino
acid levels were above current recommendations in the
starter and grower phase. The question arose whether
this repeatedly observed effect in broilers could also be
a strategy for turkey feeding.
Therefore, anexperiment with maleBUT Big 6 turkeys
was conducted in which various feeding regimens with
typical reduced, or enhanced balanced protein levels in
phases I to VI were run to study the effects on weight
gain,feed consumption,and carcassquality. Inaddition,
some economic scenarios were calculated.
MATERIALS AND METHODS
The experimental design included 6 feeding regimens
(Table 1) covering a 22-wk period and comprised 6
phases: phase I (1 to 2 wk), phase II (3 to 5 wk), phase
III (6 to 9 wk), phase IV (10 to 13 wk), phase V (14 to
17 wk), and phase VI (18 to 22 wk). Treatment 1 was
the control in which the levels of the essential amino
acids were based on the control feed of the previous
experiment (Lemme et al., 2004). In treatments 2 to 6,
the dietary amino acid profiles were varied by 10 to 20%
in single phases as shown in Table 1. Treatment 6, in
which amino acids were reduced during phases I to III,
was included to examine the potential for compensa-
tory growth.
Experimental diets were produced in a commercial
feedmill(ThemannKraftfutterGmbH,Bo ¨sel,Germany),
and consisted mainly of wheat, corn, and soybean meal,
but potato protein, soybean protein, and crystalline
amino acids were also used (Table 2). In the 90% diets,
dietary essential amino acids were reduced by 10%,
whereas in the 120% diets, they were increased by 20%.
All other nutrients and energy were maintained at the
same level and were in line with recommendations (Kar-
tzfehn, 2002). Diet formulations were adjusted to ana-
lyzed amino acid contents of the raw materials (Fontaine
et al., 2001). No antimicrobial growth promoters were
used. Because of high wheat levels, nonstarch polysac-
charide-degrading enzymes were added. Compound
feeds were analyzed for amino acids (Llames and Fon-
taine, 1994; Fontaine et al., 1998) and results confirmed
a successful feed production. Feeds were provided by
a fully automated system, and turkeys were provided
with feed and water ad libitum.
The experiment was conducted at the research facility
of Moorgut Kartzfehn (Bo ¨sel, Germany). A total of 1,848
male 1-d-old BUT Big 6 turkeys were distributed to 24
floor pens such that average weight and variability was
as similar as possible between pens and treatments. The
treatment groups were assigned to the pens using a
randomized block design. The animals originated from
the same hatch of one parent flock, and their beaks were
treated. The lighting program was in accordance with
the breeder’s recommendation. The 23.5-m2pens (3.3
birds/m2)werecoveredwithshavings.Birdsweremoni-
tored daily for sickness and mortality. Dead birds and
those showing severe weakness were removed from the
pens to avoid cannibalism, because space for escape was
limited in the floor pens.
Ten birds per pen were randomly selected on d 15,
37, and 63 to determine BW. Selecting only 10 turkeys
allowed for minimizing stress imposed on the birds. At
termination of the experiment, all birds were weighed
individually. Feed consumption was recorded per pen
for the individual phases. Feed conversion was adjusted
for mortality by adding the weight of dead birds to the
total pen weight of the remaining turkeys. Individual
feed intake was calculated on a pen basis by multiplying
the average final weight and average feed conversion
ratio. After overnight fasting, 20 birds per treatment
were slaughtered in a commercial slaughterhouse (Vel-
isco Geflu ¨gel GmbH and Co KG, Ahlhorn, Germany).
Carcass proportions were determined by weighing the

Page 3

LEMME ET AL.
654
Table 2. Experimental diets
Phase IPhase II
Ingredients (%)90%100%120%90%100% 120%
Wheat
Corn
Wheat bran
Soybean meal
Soybean protein
Potato protein
Yeast
Fat sources
DL-Met
L-Lys HCl
L-Thr
Limestone
Monocalcium phosphate
Premix1
Filler
Calculated nutrients (%) and energy
ME, MJ/kg
Ether extract
Crude fiber
CP
Lys
Met
Met + Cys
Thr
Trp
Arg
Ile
Val
Leu
Phe
His
Calcium
Phosphorus
Ratios to lysine
Lys
Met
Met + Cys
Thr
Trp
Arg
Ile
Val
Leu
Phe
His
16.18
27.38
0.00
34.28
10.00
2.00
2.00
0.65
0.26
0.14
0.08
2.02
2.53
0.98
1.50
20.23
15.00
0.00
41.80
10.00
2.00
2.00
1.58
0.30
0.11
0.09
2.01
2.40
0.98
1.50
10.00
10.00
0.00
55.15
10.00
3.09
2.00
2.63
0.37
0.00
0.07
2.01
2.19
0.99
1.50
26.45
22.00
1.00
29.93
10.00
1.04
1.00
1.63
0.23
0.15
0.04
1.76
2.55
1.22
1.00
26.40
15.00
0.00
37.58
10.00
1.00
1.00
2.23
0.27
0.10
0.03
1.76
2.47
1.16
1.00
13.15
12.45
0.00
50.50
12.00
1.00
1.00
3.35
0.34
0.00
0.01
1.74
2.25
1.21
1.00
11.3
4.71
3.60
26.10
1.62
0.63
1.04
1.05
0.33
1.72
1.14
1.24
2.08
1.31
0.67
1.40
1.00
11.3
5.39
3.65
29.00
1.80
0.70
1.15
1.17
0.37
1.95
1.28
1.38
2.25
1.46
0.74
1.40
1.00
11.3
6.30
3.78
34.80
2.16
0.85
1.38
1.40
0.45
2.40
1.55
1.67
2.69
1.76
0.89
1.40
1.00
11.6
5.54
3.51
23.90
1.44
0.59
0.85
0.91
0.31
1.58
1.03
1.12
1.86
1.19
0.61
1.30
1.00
11.6
6.00
3.52
26.60
1.60
0.63
1.05
1.01
0.34
1.79
1.15
1.25
2.05
1.32
0.68
1.30
1.00
11.6
7.38
3.73
31.83
1.92
0.79
1.26
1.21
0.41
2.22
1.40
1.50
2.44
1.59
0.83
1.30
1.00
100
39
64
65
20
106
70
77
128
81
41
100
39
64
65
21
108
71
77
125
81
41
100
39
64
65
21
111
72
77
125
81
41
100
41
59
63
22
110
72
78
129
83
42
100
39
66
63
21
112
72
78
128
83
43
100
41
66
63
21
116
73
78
127
83
43
Continued
carcass, breast meat, drums, thighs, and wings at d 155.
Body weights of selected birds were close to the respec-
tive treatment mean.
Finally, some economic calculations were run with
feed prices obtained from the feed mill. Accordingly,
prices ofphasesIthroughVIstandard(100%)feedswere
(per t) €250.50, €238.00, €216.00, €209.50, €195.5, and
€196.00, respectively. Although the prices of the diets
with 10% reduced balanced protein (phases I, II, III, V,
and VI) decreased to €240.00, €229.00, €208,00, €191.00,
and €192.00, per t, respectively, a 20% increase in bal-
anced protein increased prices to €296.00, €274.00,
€235.00, and €225.00 per t for phase I through phase IV,
respectively. For calculation of income over feed cost
(IOFC), prices of €1.05/kg of BW and €5/kg of breast
meat were assumed. The IOFC was calculated in 2 ways:
1) IOFC per pen based on breast yield: (final bird weight,
kg × carcass yield, % of live weight × breast meat yield,
% of carcass × final number of birds per pen × price/kg
of breast meat) – Σphase I –phase VI(feed intake per pen per
phase × feed cost); and 2) IOFC per bird: IOFC per pen/
number of birds. The IOFC was also calculated on basis
of BW. The reason to present calculations on a pen basis
was to include the effect of mortality.
Another indicator for economic assessment is the Eu-
ropean efficiency factor (EEF) calculated as: (final bird
weight, kg × livability, %)/(age, days × feed conversion
ratio × 100).
The data were treated by ANOVA and a multiple
rangetest (leastsignificantdifference) usingappropriate
software (WinStat 1999.2, for Microsoft Excel, Microsoft
Corp., Redmond, WA). Pen was the experimental unit,
and P < 0.05 was considered statistically significant. Be-
fore ANOVA, final individual weight gain data were
checked for outliers (outside ± 2 SD) by pen. For treat-
ment 3, one pen was considered an outlier and removed

Page 4

AMINO ACID FEEDING PROGRAMS IN TURKEYS
655
Table 2 (Continued). Experimental diets
Phase IIIPhase IV
Ingredients (%) 90%100%120%100%120%
Wheat
Corn
Wheat bran
Soybean meal
Soybean protein
Fat sources
DL-Met
L-Lys HCl
L-Thr
Limestone
Monocalcium phosphate
Premix1
Calculated nutrients (%) and energy
ME, MJ/kg
Ether extract
Crude fiber
CP
Lys
Met
Met + Cys
Thr
Trp
Arg
Ile
Val
Leu
Phe
His
Calcium
Phosphorus
Ratios to lysine
Lys
Met
Met + Cys
Thr
Trp
Arg
Ile
Val
Leu
Phe
His
36.73
20.00
1.98
28.08
5.00
2.80
0.20
0.32
0.10
1.89
1.72
1.18
41.15
10.50
0.00
34.78
5.00
3.20
0.24
0.29
0.10
1.88
1.68
1.18
25.58
10.00
0.00
49.50
5.00
4.78
0.30
0.22
0.09
1.87
1.49
1.17
47.83
11.00
0.50
27.80
3.00
4.40
0.22
0.33
0.08
1.86
1.80
1.18
34.90
10.00
0.00
41.31
3.00
5.55
0.27
0.24
0.05
1.85
1.63
1.20
11.9
5.76
3.35
21.60
1.31
0.50
0.86
0.86
0.27
1.38
0.89
0.98
1.66
1.03
0.54
1.20
0.80
12.0
5.89
3.25
24.07
1.45
0.56
0.96
0.96
0.31
1.57
1.01
1.10
1.81
1.15
0.60
1.20
0.80
12.0
7.43
3.49
28.85
1.74
0.68
1.14
1.15
0.38
1.97
1.25
1.34
2.20
1.42
0.74
1.21
0.80
12.3
6.71
3.09
20.94
1.25
0.50
0.86
0.80
0.26
1.32
0.85
0.94
1.55
0.99
0.51
1.20
0.80
12.3
7.82
3.27
25.30
1.50
0.61
1.02
0.96
0.32
1.68
1.07
1.16
1.90
1.24
0.65
1.20
0.80
100
38
66
66
21
105
68
75
127
79
41
100
39
66
66
21
108
70
76
125
79
41
100
39
66
66
22
113
72
77
126
82
43
100
40
69
64
21
106
68
75
124
79
41
100
41
68
64
21
112
71
77
127
83
43
Continued
from data analysis because performance was substan-
tially lower (18.11 kg of BW) compared with the re-
maining 3 pens (20.36 kg of BW).
RESULTS AND DISCUSSION
Data on BW of the male turkeys at d 15, 37, and 63 are
shown in Table 3. Birds of treatment 6 seemed to grow as
well as those of the control treatment during phases I and
II (d 15 and 37). However, feeding 90% amino acids in
phase III resulted in birds about 200 g lighter than birds
fed the control diet, or about 500 g lighter than those of
treatments 2, 3, 4, or 5 that received diets with 20% in-
creased amino acid levels. Only in treatment 4 amino acid
levels were at 100% during phase III. However, there
seemed to be a trend that the level of dietary amino acids
fed from phase I to III was reflected in the weight gain of
the birds in the first 3 phases, confirming observations in
broilers (Wijtten et al., 2004a,b). In general, performance
levels were below those suggested by the breeder, which
are 0.39, 1.92, and 5.86 kg after 2, 5, and 9 wk of age,
respectively (BUT, 2005).
Final BW after 22 wk ranged between 20.07 and 20.78
kg, which was 4.3 to 7.6% below the target weight sug-
gested by BUT (2005), but it was still acceptable from a
practical point of view (Table 4). Interestingly, the effects
of the amino acid supply observed after 2, 5, and 9 wk
were not apparent in the final weights. Growth perfor-
mance of treatment 1 (control) and treatment 6 were iden-
tical suggesting that the treatment 6 birds were able to
compensate the 200-g difference after 9 wk. This was not
due to a significantly increased feed intake indicating
compensatory growth (Table 4, Figure 1). In addition,
althoughgrowthandcorrectedfeedconversionweresim-
ilar between both treatments, mortality was numerically
lower in treatment 6 compared with the control as well
as with the other treatments (for the latter, P < 0.10).
Research on this topic is scarce. Moran (1981) reported
a trial in which dietary protein levels during four 2-wk
periods were varied until 8 wk of age, after which all

Page 5

LEMME ET AL.
656
Table 2 (Continued). Experimental diets
Phase VPhase VI
Ingredients (%)90%100% 90%100%
Wheat
Corn
Wheat bran
Soybean meal
Fat sources
DL-Met
L-Lys HCl
L-Thr
Limestone
Monocalcium phosphate
Premix2
Calculated nutrients (%) and energy
ME, MJ/kg
Ether extract
Crude fiber
CP
Lys
Met
Met + Cys
Thr
Trp
Arg
Ile
Val
Leu
Phe
His
Calcium
Phosphorus
Ratios to lysine
Lys
Met
Met + Cys
Thr
Trp
Arg
Ile
Val
Leu
Phe
His
52.30
19.30
2.00
16.36
4.78
0.16
0.38
0.09
1.73
1.72
1.18
57.18
8.10
3.17
21.00
5.50
0.18
0.35
0.07
1.66
1.61
1.18
57.78
15.00
1.11
14.88
6.50
0.13
0.30
0.04
1.48
1.59
1.19
57.70
12.00
0.00
19.13
6.50
0.15
0.27
0.05
1.46
1.55
1.19
12.6
6.77
3.00
16.60
1.00
0.41
0.72
0.63
0.18
0.96
0.62
0.73
1.24
0.73
0.38
1.13
0.75
12.6
7.24
3.07
18.43
1.10
0.44
0.78
0.69
0.21
1.11
0.71
0.82
1.33
0.82
0.43
1.10
0.75
13.0
8.33
2.81
14.94
0.87
0.35
0.63
0.53
0.17
0.87
0.57
0.66
1.09
0.70
0.36
1.01
0.70
13.0
8.39
3.18
16.00
0.95
0.39
0.69
0.55
0.18
0.94
0.64
0.73
1.20
0.78
0.40
1.01
0.70
100
41
72
63
18
96
62
73
124
73
38
100
40
71
63
19
101
65
75
121
75
39
100
40
72
61
20
100
66
76
125
80
41
100
41
73
58
19
99
67
77
126
82
42
1Premix for phases I through IV provided per kilogram of diet: vitamin A, 13,500 IU; vitamin D3, 4,500 IU;
vitamin E, 100 mg; thiamine, 4 mg; riboflavin, 10 mg; pyridoxine, 8 mg; vitamin B12, 30 ?g; choline chloride,
500 mg; nicotinic acid, 50 mg; pantothenic acid, 20 mg; folic acid, 1.8 mg; biotin, 220 ?g; vitamin K3, 5 mg; iron,
40 mg; copper, 15 mg; manganese, 80 mg; zinc, 100 mg; iodine, 2 mg; cobalt, 0.2 mg; and selenium, 0.25 mg.
2Premix for phases V and VI provided per kilogram of diet: vitamin A, 10,000 IU; vitamin D3, 3,000 IU;
vitamin E, 60 mg; thiamine, 3 mg; riboflavin, 6 mg; pyridoxine, 5 mg; vitamin B12, 30 ?g; choline chloride, 500
mg; nicotinic acid, 55 mg; pantothenic acid, 11 mg; folic acid, 1.5 mg; biotin, 150 ?g; vitamin K3, 4 mg; iron, 25
mg; copper, 15 mg; manganese, 70 mg; zinc, 60 mg; iodine, 0.8 mg; cobalt, 0.4 mg; and selenium, 0.25 mg.
turkeys were fed the same diet. The regimens varied be-
tween 32 to 32 to 28 to 28% and 28 to 26 to 24 to 22%
dietary protein. Although genetic potential has consider-
ably changed (Nixey, 2002) and diets were not balanced
except for Met, Moran (1981) also reported decreasing
BW at 8 wk of age with decreasing dietary protein levels,
whereas these differences were completely compensated
for at termination of that experiment after 14 wk. For
carcass proportions, slight advantages were reported for
the treatments with lowered dietary protein. In their re-
view about restricted feeding in turkeys, Plavnik and
Hurwitz (1994) reported that turkeys were generally able
to compensate early feed restrictions including protein
restriction. Waldroup et al. (1998) also investigated the
potentialforcompensatorygrowthandfinalperformance
at 18 wk; breast meat yield suggested that protein restric-
tion to 75% of NRC (1994) recommendation from 0 to 3
wk could be compensated for by feeding 110 or 120%
amino acids after the restriction period. Although for all
restriction programs, increasing BW and breast meat
yields could be demonstrated with increasing amino acid
levels, compensatory growth was not complete when re-
strictions lasted from 0 to 6 wk or from 6 to 12 wk (Wal-
droup et al., 1998). However, considering the severe pro-
tein reduction to 75% of NRC (1994), the potential for
compensation still appears huge. Another interesting
finding by Waldroup et al. (1998) was that protein restric-
tions significantly decreased leg disorders, particularly
when applied from 0 to 6 and 6 to 12 wk. In the current
trial, mortality was numerically decreased in treatment