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Determination of degradability of treated soybean meal and
its proteins fractions
Ramin Salamatdoust Nobar1*,
Mohammad Chamani1, Ali-Asghar Sadeghi1
and Ali Mirza-Aghazadeh2
1Department
of Animal Science, Islamic Azad University- Science
and Research Branch, Tehran,
Iran.
2Department
of Animal Science, Urmia University, Urmia,
Iran.
*Corresponding
author. E-mail:
salamatdoust@gmail.com.
Accepted 21 November, 2008 |
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This study was
carried out to determine the effects of xylose and moisture
heating treatments (0, 5 and 10 g/kg DM) of soybean meal (SBM)
on in situ rumen degradability characteristics in cow
and its proteins sub-units fractions by a SDS-PAGE
discontinues system. In the experiments, three ruminally
cannulated
male Taleshi cow were used to measure in situ rumen
degradability characteristics of dry matter (DM) and crude
protein (CP) of different treated SBM samples. SBM were
treated with xylose (5 and 10 g/kg DM) and moisture heating.
Xylose and moisture heated treatment significantly (P<0.05)
reduced degradability values of DM and CP for SBM. Rumen
effec-tive
protein degradability values of SBM (k = 0.02, 0.05 and 0.08
h-1) were significantly decreased by all
treatments (P<0.05). Effective degradability of DM (k = 0.05
h-1) were 65.17, 64.90, 61.77 and 58.50
g/kg and CP was 63.77,
61.97, 60.83 and 60.23 g/kg
for NTSBM (non treated SBM), TSBM
(SBM + 30 min moisture heating treated), TSBM 5 g/kg (SBM +
30 min moisture heating treated + 5 g/kg xylose)
and TSBM 10 g/kg (SBM + 30 min moisture heating treated + 10
g/kg xylose) treatments,
respectively. Treatment of SBM with 5 and 10 g/kg of
DM caused a reduction in the dry matter and effective crude
protein degradability compared with NTSBM. Electrophoretic
patterns of untreated and treated SBM protein residues
revealed that β-conglycinin β, α and ά subunit were degraded
completely within 4h of incubation in the rumen, whereas
the acidic and basic subunits of glycinin were degraded
after 48h incubation in treated SBM with Xylose. It is
concluded that SBM proteins can be effectively protected
from degradation in the rumen by xylose and moisture heating
treatment.
Key words:
Soybean meal, degradability, xylose, moisture heat, SDS-PAGE. |
