URGENT NEWS
1 of 4
Issue date: 15/10/12
No 175: Update on Wheat Quality 2012 - 2013
Predicting Nutrient
Content from Bushel
Weight
Since our first review of the quality of new crop wheat
(Urgent News 171), many more samples have been
analysed in the FWTNI laboratory. There is a very wide
range in the quality of the wheats being offered for
livestock feeding. Many are of low bushel weight and
well below the minimum industry standard of 72kg/
hl; the nutrient values of these wheats for all classes of
livestock is an issue, particularly when bushel weight is
the only measured parameter.
Firstly, it is clear that for wheat of bushel weight above
72 kg/hl, starch (Fig.1) and energy (Fig. 2) content do
not change as bushel weight increases.
Fig 1: Starch vs Bushel Wt (>72kg/hl)
As bushel weight declines from 72 to 54 kg/hl, nutrient
content (starch, protein, oil, fibre and ash) changes
only a little. No nutrient was strongly correlated to
bushel weight, although oil (r2 0.136 Fig 3) and starch
(r2 0.10 Fig 4) tended to decline whilst protein tended
to increase (r2 0.06 Fig 5) with declining bushel weight.
Clearly these are very weak relationships and highlight
the need for nutrient analysis rather than purely bushel
weight to evaluate the value of these lower quality
wheats.
Fig 3: Oil vs Bushel Wt <72kg/hl
Wheat Samples <72kg/hl
2.50
2.30
2.10
1.90
1.70
Oil % 1.50
1.30
1.10
0.90
0.70
0.50
R² = 0.1363
50.0
55.0
Wheat Samples >72kg/hl
65.00
63.00
61.00
59.00
57.00
Starch (%)
55.00
53.00
51.00
49.00
47.00
45.00
60.0
65.0
70.0
75.0
Bushel Weight (kg/hl)
Fig 4: Starch vs Bushel Wt <72kg/hl
Wheat Samples <72kg/hl
70.00
y = 0.2794x + 36.919
R² = 0.0512
R² = 0.1004
65.00
60.00
70.0
72.0
74.0
76.0
78.0
80.0
Bushel Weight (kg/hl)
Starch % 55.00
50.00
45.00
Fig 2: Energy vs Bushel Wt (>72kg/hl)
40.00
Wheat Samples >72kg/hl
50.0
55.0
60.0
65.0
Bushel Weight (kg/hl)
13.40
13.20
13.00
12.80
12.60
Rel.CVB ME
12.40
(MJ/kg)
12.20
12.00
11.80
11.60
11.40
y = -0.0013x + 13.15
R² = 0.0003
70.0
72.0
74.0
76.0
78.0
Bushel Weight (kg/hl)
Frank Wright Trouw Nutrition International
Blenheim House, Blenheim Road, Ashbourne, Derbyshire DE6 1HA
Tel: 01335 341 102
Fax: 01335 341 171
Email: [email protected]
Website: www.frankwrighttrouw.com
80.0
70.0
75.0
URGENT NEWS
2 of 4
Issue date: 15/10/12
No 175: Update on Wheat Quality 2012 - 2013
Fig 5: Protein vs Bushel wt <72kg/hl
Fig 6: Starch vs Bushel wt 65 to 72kg/hl
WheatSamples
Samples<72kg/hl
<72kg/hl
Wheat
16.00
16.00
15.00
15.00
14.00
14.00
13.00
13.00
12.00
12.00
11.00
Protein
Protein %
% 11.00
10.00
10.00
9.00
9.00
8.00
8.00
7.00
7.00
6.00
6.00
50.0
50.0
Wheat Samples 65 to 72kg/hl
65.00
63.00
61.00
59.00
57.00
Starch (%)
55.00
53.00
51.00
49.00
47.00
45.00
= 0.06
R²R²
= 0.06
55.0
55.0
60.0
65.0
60.0
65.0
Bushel
BushelWeight
Weight(kg/hl)
(kg/hl)
70.0
70.0
75.0
75.0
y = 0.1293x + 46.996
R² = 0.0037
64.0
66.0
68.0
70.0
72.0
Closer evaluation of the results suggests that wheats
with a bushel weight below 72 kg/hl can be better
characterised in 2 groups - 72 to 65kg/hl and less
than 65kg/hl. Whilst the first group of wheats have
marginally lower average values for starch and energy
(AMEn by the CVB equation adjusted relative to UK
standards), there is little apparent difference between
65 and 72 kg/hl bushel weight wheat, albeit with wide
variation within the group (figs 6 & 7).
Fig 7: AME vs Bushel wt 65 to 72kg/hl
Wheat Samples 65 to 72kg/hl
13.40
13.20
13.00
12.80
12.60
Rel.CVB ME
12.40
(MJ/kg)
12.20
12.00
11.80
11.60
11.40
y = 0.0118x + 12.09
R² = 0.0148
64.0
66.0
68.0
70.0
Bushel Weight (kg/hl)
Table 1: Nutrient Values of Wheats by Bushel Weight
Bushel Wt
Starch
Crude
protein
Oil
Moisture
Rel.CVB
AMEn
kg/hl
%
%
%
%
MJ/kg
72.0
57.50
11.00
1.60
14.00
12.85
Average
74.3
57.69
11.39
1.50
12.52
13.05
Min.
72.0
50.50
9.46
1.21
11.01
12.77
Max.
79.1
61.20
13.89
1.83
14.05
13.32
Ref Standard
>72kg/hl
>65 to <72kg/hl Average
<65kg/hl
68.1
55.81
11.52
1.56
12.97
12.89
Min.
65.1
48.70
8.60
1.23
11.04
12.53
Max.
71.8
63.10
14.79
2.14
15.03
13.26
Average
60.0
53.71
12.09
1.38
15.55
12.47
Min.
54.0
46.60
7.78
0.95
11.56
11.63
Max.
64.9
60.40
14.70
1.88
21.30
13.14
Frank Wright Trouw Nutrition International
Blenheim House, Blenheim Road, Ashbourne, Derbyshire DE6 1HA
Tel: 01335 341 102
Fax: 01335 341 171
Email: [email protected]
Website: www.frankwrighttrouw.com
74.0
Bushel Weight (kg/hl)
72.0
74.0
URGENT NEWS
3 of 4
Issue date: 15/10/12
No 175: Update on Wheat Quality 2012 - 2013
Fig 8: Starch vs Bushel wt <65kg/hl
For Pigs: The evidence would suggest that when
bushel weight falls below 70kg/hl, there is an argument
for reducing the energy value of the wheat by 0.1-0.2
MJ/kg NE. Additionally, as bushel weight falls below
70kg/hl the variation in energy value increases greatly
(fig 10).
Wheat Samples <65kg/hl
65.00
63.00
61.00
59.00
57.00
Starch (%)
55.00
53.00
51.00
49.00
47.00
45.00
y = 0.235x + 39.614
R² = 0.0544
Fig 10: Relationship between bushel weight and
net energy value of wheat for pigs.
Wheat Samples <72kg/hl
52.0
54.0
56.0
58.0
60.0
62.0
64.0
66.0
10.40
Bushel Weight (kg/hl)
R² = 0.3188
10.20
10.00
9.80
Fig 9: AME vs Bushel wt <65kg/hl
Net Energy 9.60
(MJ/kg)
9.40
9.20
Wheat Samples <65kg/hl
13.40
13.20
13.00
12.80
12.60
Rel.CVB ME
12.40
(MJ/kg)
12.20
12.00
11.80
11.60
11.40
9.00
8.80
y = 0.0525x + 9.3209
R² = 0.2268
8.60
50.0
55.0
60.0
65.0
70.0
75.0
Bushel weight (kg/hl)
Table 2 Bushel weight and energy value of
wheat for pigs.
52.0
54.0
56.0
58.0
60.0
62.0
64.0
66.0
Bushel Weight (kg/hl)
Conversely, the very low bushel weight wheat samples
(<65kg/hl) have a lower starch content which tends to
decline with bushel weight. Unsurprisingly, this results
in much lower predicted relative energy values for
poultry. The correlations remain very weak, reaching r2
of 0.23 for AMEn (figs 8 & 9).
For Poultry: On the basis of the current data set,
there is no clear evidence to predict a reduction in the
AMEn of wheat for poultry until the bushel weight falls
below 65kg/hl. However, increased variability in starch
content, and therefore AMEn, can be expected when
the bushel weight falls below 72kg/hl and there may
be circumstances where it may be prudent to apply, for
formulation purposes, a reduction of 0.1 to 0.2 MJ/kg
in the AMEn value for wheat.
Frank Wright Trouw Nutrition International
Blenheim House, Blenheim Road, Ashbourne, Derbyshire DE6 1HA
Tel: 01335 341 102
Fax: 01335 341 171
Email: [email protected]
Website: www.frankwrighttrouw.com
Bushel
weight
kg/hl
Mean bushel
weight
Mean NE
MJ/kg
Mean DE
MJ/kg
<70
64.16
9.69
13.58
>70
74.65
9.96
13.86
For Ruminants: This data may be used in a more
simplistic manner to predict the starch and MER values
in wheat of below 72 kg/hl bushel weight. A simple
regression approach has been used to predict starch
and poultry energy as bushel weight declines from 72
kg/hl (figs 4 and 11). The % change in AMEn was then
applied as the % change in MER with falling bushel
weight. In summary, each 2kg/hl reduction in bushel
weight approximates to a 0.5% reduction in starch
content and 0.1 MJ/kg FM reduction in MER (Table
3). As with poultry, the largest impact may only occur
when bushel weights fall below 65 kg/hl.
URGENT NEWS
4 of 4
Issue date: 15/10/12
No 175: Update on Wheat Quality 2012 - 2013
Fig 11: Energy (AME) vs Bushel wt <72 kg/hl
Further information can be obtained from the Frank
Wright Trouw technical department on 01335 341102.
Receive these technical publications directly via e-mail
link. Contact Sarah Brandrick to register your interest
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website: www.frankwrighttrouw.com
Wheat Samples <72kg/hl
13.40
13.20
13.00
12.80
12.60
Rel CVB ME
12.40
(MJ/kg)
12.20
12.00
11.80
11.60
11.40
R² = 0.4602
50.0
55.0
60.0
65.0
70.0
75.0
Bushel Weight (kg/hl)
In practice, major concern centres on the many
ruminant units that may keep poor quality cereals for
feeding on farm. In these cases, careful attention should
be paid not only to the MER of the wheat used in
ration formulation but also to the effective processing
of the grain before feeding. With small grains being
frequently seen in low quality wheats this year, cattle
will pass many undigested grains with the resultant
effect of lost nutrient value, unless attention is paid to
effective processing. Either grinding, acid treatment
before rolling using Selko Fysal Forte, or proper caustic
treatment will be essential on many farms this winter.
Table 3: Bushel Weight, Starch & ME for
Ruminants
Ref
Regression
Regression
Equivalent
(r2 = 0.10)
(r2 = 0.46)
from AME
Bushel
Wt
Starch
CVBr AME
AME
change
MER
kg/hl
%
MJ/kg
%
MJ/kg
72
57.5
12.85
72
56.7
13.1
0.0
11.8
70
56.2
13.0
0.7
11.7
68
55.7
12.9
1.5
11.6
66
55.2
12.8
2.2
11.5
64
54.8
12.7
3.0
11.4
62
54.3
12.6
3.7
11.4
60
53.8
12.5
4.5
11.3
11.8
Frank Wright Trouw Nutrition International
Blenheim House, Blenheim Road, Ashbourne, Derbyshire DE6 1HA
Tel: 01335 341 102
Fax: 01335 341 171
Email: [email protected]
Website: www.frankwrighttrouw.com