Distillers dried grains with solubles (DDGS) is a co-product from the dry-grind ethanol production. However, quality and nutrient content of DDGS may differ among sources and origins and new technologies allow for production of DDGS with different chemical compositions as well as nutritional values. Recently a high-protein distillers dried grains (HP-DDG; ProCap DDGS, Marquis Energy, Hennepin, IL) was introduced and the HP-DDG has greater concentrations of CP and fat, but contains less fiber compared with conventional DDGS, which may affect the digestibility of AA in HP-DDG compared with conventional DDGS. There are, however, no data for the digestibility of AA in this new source of DDGS. Therefore, the objective of this research was to test the hypothesis that standardized ileal digestibility (SID) of AA in HP-DDG is greater than in conventional DDGS when fed to growing pigs.
Experimental design
Nine growing pigs (initial BW: 67.2 ± 6.4 kg) with a T-cannula installed in the distal ileum were allotted to a triplicate 3 × 3 Latin square design with 3 diets and 3 periods. There were 3 pigs per diet in each period for a total of 9 observations per treatment. Experimental diets included each source of DDGS as the sole source of AA, and a nitrogen-free diet was used to measure the basal endogenous losses of AA.
Each experimental period lasted 6 d. The initial 4 d of each period was considered an adaptation period. Ileal digesta were collected on d 5 and 6 for 9 h using standard procedures. The diets and digesta were analyzed for AA and Cr to calculate the apparent ileal digestibility (AID) of CP and AA in the 2 sources of DDGS. The AID values were then corrected using the basal endogenous losses of CP and AA to calculate the SID values.
Results
Based on 88% DM basis, HP-DDG contained more CP, AA, and acid-hydrolyzed ether extract compared with conventional DDGS (Table 1). The AID and SID of all AA in HP-DDG were greater (P < 0.001) than in conventional DDGS with the exception that the AID and SID of Pro were not different between the 2 sources of DDGS (Table 2).
The very high concentrations of AA and SID values for AA in HP-DDG obtained in this experiment indicate that HP-DDG is of very high quality and may be a great source of digestible AA in diets fed to pigs.
Key points
- A new source of DDGS (i.e., HP-DDG) contains more CP, AA, and fat compared with conventional DDGS.
- HP-DDG has greater values for SID of CP and AA compared with conventional DDGS.
Table 1. Nutrient composition of HP-DDG and conventional DDGS1
|
Item, % |
HP-DDG |
Conventional DDGS |
|---|---|---|
|
Dry matter |
94.6 |
87.6 |
|
Crude protein |
48.1 |
31.1 |
|
Acid-hydrolyzed ether extract |
9.49 |
4.14 |
|
Indispensable AA |
||
|
Arg |
2.47 |
1.35 |
|
His |
1.40 |
0.78 |
|
Ile |
2.03 |
1.13 |
|
Leu |
5.57 |
3.24 |
|
Lys |
1.89 |
1.03 |
|
Met |
1.09 |
0.54 |
|
Phe |
2.51 |
1.33 |
|
Thr |
1.89 |
1.09 |
|
Trp |
0.49 |
0.20 |
|
Val |
2.84 |
1.46 |
|
Dispensable AA |
||
|
Ala |
3.41 |
2.00 |
|
Asp |
3.38 |
1.94 |
|
Cys |
1.00 |
0.57 |
|
Glu |
7.52 |
4.32 |
|
Gly |
2.06 |
1.17 |
|
Pro |
3.52 |
2.21 |
|
Ser |
2.20 |
1.29 |
|
Tyr |
1.90 |
0.97 |
|
d |
d |
d |
1All values except DM were adjusted to 88% DM.
Table 2. AID and SID of CP and AA in HP-DDG and conventional DDGS (n = 9)
|
|
AID |
SID1 |
||||||
|---|---|---|---|---|---|---|---|---|
|
Item, % |
HP-DDG |
Conventional DDGS |
SEM |
P-value |
HP-DDG |
Conventional DDGS |
SEM |
P-value |
|
CP |
77.7 |
63.8 |
2.0 |
< 0.001 |
84.4 |
70.7 |
2.0 |
< 0.001 |
|
Indispensable AA |
||||||||
|
Arg |
86.7 |
72.8 |
2.3 |
< 0.001 |
92.0 |
79.1 |
2.3 |
< 0.001 |
|
His |
85.8 |
70.0 |
1.6 |
< 0.001 |
88.1 |
72.6 |
1.6 |
< 0.001 |
|
Ile |
84.4 |
70.2 |
1.3 |
< 0.001 |
87.3 |
73.6 |
1.3 |
< 0.001 |
|
Leu |
88.1 |
80.7 |
1.0 |
< 0.001 |
89.8 |
82.6 |
1.0 |
< 0.001 |
|
Lys |
81.0 |
55.7 |
1.8 |
< 0.001 |
84.8 |
60.2 |
1.8 |
< 0.001 |
|
Met |
87.7 |
78.2 |
0.9 |
< 0.001 |
89.4 |
80.1 |
0.9 |
< 0.001 |
|
Phe |
87.2 |
77.1 |
0.9 |
< 0.001 |
89.4 |
79.7 |
0.9 |
< 0.001 |
|
Thr |
77.7 |
61.3 |
1.7 |
< 0.001 |
82.6 |
66.7 |
1.7 |
< 0.001 |
|
Trp |
86.4 |
72.0 |
1.3 |
< 0.001 |
90.2 |
76.4 |
1.3 |
< 0.001 |
|
Val |
81.8 |
66.1 |
1.5 |
< 0.001 |
85.3 |
70.5 |
1.5 |
< 0.001 |
|
Total |
85.0 |
72.0 |
1.3 |
< 0.001 |
88.0 |
75.5 |
1.3 |
< 0.001 |
|
Dispensable AA |
||||||||
|
Ala |
82.0 |
73.3 |
1.7 |
< 0.001 |
85.7 |
77.3 |
1.7 |
< 0.001 |
|
Asp |
77.6 |
60.9 |
1.6 |
< 0.001 |
81.7 |
65.4 |
1.6 |
< 0.001 |
|
Cys |
80.4 |
65.2 |
1.6 |
< 0.001 |
83.9 |
68.8 |
1.6 |
< 0.001 |
|
Glu |
87.1 |
77.4 |
1.4 |
< 0.001 |
89.3 |
79.7 |
1.4 |
< 0.001 |
|
Gly |
58.7 |
39.9 |
5.0 |
< 0.001 |
75.5 |
58.7 |
5.0 |
< 0.001 |
|
Pro |
38.2 |
38.4 |
10.8 |
0.958 |
72.5 |
71.6 |
10.8 |
0.850 |
|
Ser |
82.2 |
69.0 |
1.8 |
< 0.001 |
86.3 |
73.5 |
1.8 |
< 0.001 |
|
Tyr |
87.5 |
79.1 |
0.8 |
< 0.001 |
90.3 |
81.9 |
0.8 |
< 0.001 |
|
Total |
75.2 |
64.6 |
2.9 |
< 0.001 |
83.8 |
73.8 |
2.9 |
< 0.001 |
|
Total AA |
79.8 |
67.9 |
2.1 |
< 0.001 |
85.8 |
74.5 |
2.1 |
< 0.001 |
|
b |
b |
b |
b |
b |
b |
b |
b |
|
1Values for SID were calculated by correcting the values for AID for basal ileal endogenous losses. Basal ileal endogenous losses were determined (g/kg of DMI) as CP, 11.91; Arg, 0.46; His, 0.12; Ile, 0.21; Leu, 0.34; Lys, 0.26; Met, 0.06; Phe, 0.20; Thr, 0.34; Trp, 0.07; Val, 0.36; Ala, 0.45; Asp, 0.51; Cys, 0.12; Glu, 0.62; Gly, 1.26; Pro, 4.35; Ser, 0.32; and Tyr, 0.17.