"Site
of Digestion in Dairy
Cows Fed Different
Soy-Protein Supplements" [digestibility,
lysine, expeller, roasted soybeans]
Cannulated
dairy cattle were used to evaluate the
site and extent of digestion of various
soy-protein supplements including solvent
extract soybean meal (SSBM), expeller
soybean meal (ESBM), nonenzymatically
browned soybean meal (SoyPass), and
whole roasted
soybeans (WRSB).
Soya
Protein Sources
SSBM
ESBM
SoyPass
WRSB
N intake,
g/d
579
622
613
567
~
Passage to duodenum ~
NAN, g/d
467
514
564
498
NAN, % of N intake
81.6
85.2
95.8
88.1
NANMN, g/d
222
283
323
289
NANMN, % of N
intake
40.0
47.4
56.0
51.0
Microbial N, g/d
245
227
236
209
Microbial N, g/kg
OMTD
25.4
22.2
25.2
22.4
Total AA, g/d
2390
2478
2953
2640
Essential AA,
g/d
1163
1179
1409
1279
Lysine, g/d
166
164
197
186
Methione, g/d
58
59
64
61
SoyPass
delivered the highest percentage dietary
protein the duodenum (NANMN) without
having any negative impact on microbial
synthesis. The net result was a higher
level of essential amino acids delivered
to the duodenum, particularly lysine,
but also methionine.
I.
R. Ipharraguerre, J. H. Clark, and
D. E. Freeman, (2004), J Anim Sci
82, Suppl. 1, 214.
