Soybean Meal Quality Measurements
Korean research examined various methods to evaluate the quality of
soybean meal in growing pig diets. Five different heat-treated soy flake
treatments were prepared to provide different levels of heat denaturalization
(1) raw; (2) steamed for five minutes at 950C; (3) steamed for 15 minutes
at 11 00C; (4) steamed for 15 minutes at 1100C; and (5) steamed for
60 minutes at 110∞C. Twenty barrows weighing 14.1± 0.9
kg were randomly assigned to the dietary treatments. The pigs were fed
the diets for three days prior to fecal and urine collection for four
days. The results indicated that pigs fed the diet containing the soy
flakes heat-treated for 15 minutes at 1100C (treatment 4) had the highest
nitrogen retention, average daily gain and average daily feed intake.
Both protein solubility in potassium hydroxide and protein dispersibility
index values were significantly (P<0.00l) inversely related to nitrogen
retention with regression correlations of -0.893 and -0.841, respectively.
Urease activity and pepsin digestibility were not correlated to nitrogen
retention in this experiment. Feed intake and feed efficiency (G/F)
values were significantly lower for the pigs fed the diet containing
raw soybean flakes. These results indicate that PDI is as effective
as KOH protein solubility as an indicator of soybean meal protein quality
for the growing pig.
|
Treatments |
1 |
2 |
3 |
4 |
5 |
| Urease activity |
1.95a |
0.10b |
0.02c |
0.03c |
0.01c |
| Pepsin digestion, % |
95.2a |
95.1a |
94.7a |
94.5a |
93.3a |
| KOH protein sol. % |
96.1a |
84.8b |
79.1c |
77.0d |
41.7e |
| PDI, % |
65.4a |
33.8b |
22.6c |
21.1c |
8.6d |
| N retention, % |
7.5c |
67.2b |
69.9ab |
71.6a |
67.5b |
| |
|
|
|
|
|
| ADG,g |
324c |
555b |
583b |
625a |
550b |
| ADFI, g |
848c |
1,039b |
1,041b |
1,128a |
1,063ab |
| G/F |
0.38b |
0.54a |
0.56a |
0.55a |
0.52a |
| (Treatments with different
subscripts are significantly different) |
Lee, H. S. and co-workers. 2004. Evaluation of protein dispersibility
index as an indicator for soybean meal protein quality in growing pigs:
I. Metabolic study. Poster T42, p174 of the 2004 Joint Annual Meeting
abstracts.
|
