This study examined the effects of adding lactic acid bacteria (LAB) and propionic acid bacteria (PAB) as inoculants to corn silage. Corn silage was treated with a control, LAB, or PAB and fermented for various durations. The silage was then analyzed to determine changes in pH, crude protein, fiber, and other nutritional components. Results showed that both LAB and PAB reduced pH during fermentation but did not significantly improve silage quality compared to the control. Crude protein decreased with longer fermentation times across all treatments. Fiber levels also declined as fermentation progressed. While the additives accelerated acid production, treating with LAB and PAB did not provide clear benefits over the untreated

1. EFFECT OF LACTIC AND PROPIONIC ACID
BACTERIA AS ADDITIVES ON CORN SILAGE
FERMENTATION
A. R. Norafizaha,b*, R. A. Halimb, M. Noranizab, N. Abdullahc, and G.Salehb
a Dept. of Livestock Biotechnology, Agro Biotechnology Institute of Malaysia (ABI), MOSTI
b Crop Science Department, Faculty of Agriculture, UPM
c Institute of Tropical Agriculture, UPM
*Corresponding Author; norafizah_r@yahoo.com
Corn-silage has been shown to be a good silage compared to fodder grasses because of its carbohydrates and sugar content which
is approximately 23% of soluble carbohydrates whereas grasses are about 3-8% only. This soluble carbohydrates are essential as a
source of energy for acid-forming bacteria to carry out successful ensilation of the substrate. Innoculation of certain types of
bacteria into the silage may hasten the ensilation process and conserve more nutrients. Microorganisms that dominate in silage
will determine the condition of silage produced by influencing the composition of fermentation acids and final pH of silage. The
objective of this study is to determine the effect of adding Lactic Acid Bacteria (LAB): L.plantarum & Propionic Acid Bacteria (PAB):
P.freudenrinchii as inoculants to improve the preservation and nutrition value of corn silage.
Forage treat with:
1) Control (WB)
2) LAB (B1)
3) PAB (B2)
Ferment in laboratory silo
5 Different fermentation
durations;
Day (D) 3,
D6, D9, D18, D27
Silage quality
determination:
-Physical: pH
-Chemical:
CP, DM, Fiber (ADF,
NDF)
Corn forage harvested at
dough stage
(Mac 2012 & June 2012)
9.01a
8.36a
8.10a
7.17a
8.12a
7.98b
7.56b
7.40b
7.04a
7.93a7.83b
8.00ab
7.26b
6.89a 7.07b
3.00
4.00
5.00
6.00
7.00
8.00
9.00
10.00
D3 D6 D9 D18 D27
(%)
Fermentation duration
CP First Season
WB
B1
B2
Figure 1: Crude protein (CP) for first season.
7.99a
7.71a
7.10b 7.04b
6.88b
5
6
7
8
D3 D6 D9 D18 D27
(%)
Fermentation duration
CP Second Season
Figure 2: Crude protein (%) of silage at different
fermentation duration for second season.
3.51a 3.46a 3.32a
3.24a
3.69a3.49a
3.51a
3.39a
3.29a
3.65a
3.51a
3.53a
3.32a
3.48a
3.34b
2.50
3.50
4.50
5.50
D3 D6 D9 D18 D27
PH Second Season
WB
B1
B2
Figure 4: pH of silage for second season.
39.74a 39.03a
36.83b 36.47b 36.44b
25.00
35.00
45.00
D3 D6 D9 D18 D27
(%)
Fermentation duration
ADF Second Season
Figure 7: Acid Detergent Fiber (ADF) of second season.
3.58b
3.65ab
3.57b 3.34d
3.39b
3.31c
3.60ab
3.52c
3.51b
3.34c
3.70a 3.68a 3.64a
3.61a
3.45a
2.50
3.00
3.50
4.00
4.50
5.00
D3 D6 D9 D18 D27
PH First Season
Control
B1
B2
Figure 3: pH of silage for first season.
WB
Both seasons showed reduction of CP content when the forage was
fermented longer. However, control treatment showed the highest CP
content at every observation days for the first season. No interaction
among bacteria and fermentation duration for CP 2nd season. All
treatments did reduce the pH value starting from D3 and remain low
at D27. NDF is slightly high in treated silage (B1 and B2) compared
with the control silage. Increases in the fiber concentration can be due
to differences in the amount of DM loss from fermentation. NDF and
ADF in second season decreases with fermentation duration which
indicates that considerable loss of fiber occurred in the ensiling
process. As a conclusion, treating with LAB and PAB did not show
much differences. Nevertheless, it is recommended to further test
with other fermentation products such as production of fermentation
acids which are important in determining silage quality.
The authors gratefully acknowledge MOSTI-ABI & UPM (grant no
09-05-ABI-AB035/ 5780038) for the funding.
Fermentation durationFermentation duration
69.49a
68.30a
64.86a 64.57a 64.43a
60.00
62.00
64.00
66.00
68.00
70.00
D3 D6 D9 D18 D27
Fermentation duration
NDF Second Season
Figure 5: Neutral detergent fiber (NDF) between treatment. Figure 6: Neutral detergent fiber (NDF) between
fermentation duration in second season.
66.11a
66.41a
66.47a
65.9
66
66.1
66.2
66.3
66.4
66.5
WB B1 B2
Treatment
NDF Second Season
(%)
(%)