The study tested the effectiveness of a protease, Ronozyme Proact, in enhancing amino acid digestibility in corn for broilers. Results showed a significant improvement of approximately 3.18% in total apparent amino acid digestibility when the protease was included in the diet. The research indicates that using 200 ppm of this protease can effectively increase the utilization of amino acids in corn-based diets for broilers.

1. Use of a protease to enhance the
utilization of corn amino acids by
broilers.
J.C.C. Carvalho1; R.L. Rios1; F.R. Mesquita1; E.M.C. Lima1; A.G.
Bertechini1; J.O.B. Sorbara*2
Universidade Federal de Lavras. MG. Brazil
2
DSM Nutritional Products. São Paulo. SP. Brazil
1

2. Abstract

3. Introduction
• Corn – mostly utilized cereal in broiler diets
• Main energy source in the feed
• Also contributes with 10 to 20% of total CP and AAs
for broilers

4. Amino Acid Digestibility Methods
• PSA 2008 and PSA 2009
– Differences higher than 5 to 15% in AA digestibility
without statistical differences
• So, how to evaluate effects of modifiers that can
improve AA digestibility in that range ?
– Precision Fed Rooster Assay – Low Feed Intake
– Standardized Ileal Assay – Semi Purified Diets

5. Objective
• This study tested the ability of a commercially
available protease to improve the protein and amino
acid digestibility of Corn

6. Material and Methods
• Metabolism Trial
• 160 Male Cobb 500
• Experimental Design
• Experimental Period
– 14 to 18 d old
adaptation period
– 19 to 21 d old total
excrete collection
– 4 treatments
– 8 replicates of 5 birds each
• Analyses
Protease
(PROT/kg)
Tr.
Ingredients
1
Reference Diet
0
2
Reference Diet
15000
3
60% Reference Diet + 40% Corn
0
4
60% Reference Diet + 40% Corn
15000
– Samples were freezedried
– Amino Acids analyzed by
HPLC (White et al.. 1986;
Hagen et al.. 1989).

7. Material and Methods
• Calculate the Total Apparent Amino Acid Digestibility:
– TAAA (TD or RD) = ingested AA– excreted AA
ingested AA
– TAAA (Ingredient)= AARD + (AATD – AARD)
g/g substitution
Where: TD – Test Diet; RD – Reference Diet;
AARD – Amino Acid in Reference Diet;
AATD – Amino Acid in Test Diet.
• Data analyzed according to SAS procedures (2001).
– Student Test (P<0.10)

8. Material and Methods
• Product Specifications
– RONOZYME ProAct is a mono component protease with 75000
PROT/g originated from Nocardiopsis prasina and produced by
the bacteria Bacillus licheniformis
– Recommend Dose 15000 PROT/kg = 200 ppm
– One ProAct activity unit (PROT) is the amount of enzyme that
releases 1 µmol of p-nitroaniline from 1 mM substrate (Suc-AlaAla-Pro-Phe-pNA) per minute at pH 9.0 and 37 °C.

9. Material and Methods
• Reference Diet Composition
Ingredients
Corn
SBM
Fat
DCP 24/18
Limestone
Salt
Mineral Premix1
Vitamins Premix1
DL-Methionine 99%
L-Lysine 78%
L-Threonine 98%
Other Additives
Choline Chloride 70%
Total
%
53.749
38.747
3.283
2.151
0.951
0.457
0.100
0.100
0.247
0.063
0.007
0.088
0.057
100.000
Calculate Content
AME. Kcal
2980
CP. %
22.00
Ca. %
1.00
Av. P. %
0.50
Na. %
0.20
Dig Lys. %
1.15
Dig TSAA. %
0.85
Dig Thr. %
0.76

10. Material and Methods
• Corn Composition
Nutrient
Fat (%)
Moisture (%)
Crude Protein (%)
3.59
11.46
8.02
Amino Acids
Aspartic Acid
Glutamic Acid
Serine
Glycine
Histidine
Arginine
Threonine
Alanine
Proline
Tyrosine
Valine
Methionine
Cystine
Isoleucine
Leucine
Phenylalanine
Lysine
Total amino acids
%
0.53
1.61
0.42
0.33
0.26
0.42
0.28
0.64
0.76
0.34
0.42
0.21
0.15
0.30
1.06
0.41
0.28
8.43

11. Material and Methods
• Corn Composition
Amino Acids
Aspartic Acid
Glutamic Acid
Serine+Glycine
Histidine
Arginine
Threonine
Alanine
Proline
Tyrosine
Valine
Methionine
Cystine
Isoleucine
Leucine
Phenylalanine
Lysine
Rostagno
et al.,
2005
0.73
0.26
0.39
0.32
0.29
0.40
0.17
0.19
0.29
1.02
0.41
0.24
%
0.53
1.61
0.75
0.26
0.42
0.28
0.64
0.76
0.34
0.42
0.21
0.15
0.30
1.06
0.41
0.28

12. Material and Methods
•Broiler raised in floor pens until
be transferred to batteries
•Receiving the same feed w/out
enzyme

13. Material and Methods
Metabolism Room
• Room of 90 m2
• Controlled environment

14. Results
• Protease effect on Total Apparent Amino Acid
Digestibility of Corn / Essential Amino Acids
Amino Acids
Digestibility Coefficient, %
CV
P
Without Protease
With Protease
Arginine
81.45
83.56
4.20 0.4211
Threonine
72.16
79.29
3.18 0.0580
Valine
81.41
84.71
2.43 0.0606
Methionine
87.31
87.48
1.64 0.8722
Cystine
75.01
79.19
1.98 0.0081
Isoleucine
82.23
85.22
1.13 0.0042
Leucine
88.33
89.48
0.93 0.0960
Phenylalanine
87.08
88.14
0.84 0.0891
Lysine
87.81
88.02
0.72 0.6483
Histidine
85.52
86.02
1.02 0.4546
Total AA
82.25
84.75
0.91 0.0036

15. Results
• Protease improvement on Total Apparent AA
Digestibility of Corn
Improvement (% Control)
– Essential Amino Acids
120%
Mean = 3.18% improvement
115%
*
110%
*
*
105%
*
100%
His
Arg
* = P≤0.10
Thr
Val
Met
Cys
Ile
*
*
Leu
Phe
Lys

16. Results
• Protease effect on Total Apparent Amino Acid
Digestibility of Corn
– Non Essential Amino Acids
Amino Acids
Digestibility Coefficient, %
Without Protease
With Protease
CV
P
Aspartic Acid
84.48
84.64
2.17 0.9104
Glutamic Acid
90.66
91.79
1.32 0.2322
Serine
79.51
83.26
1.72 0.0090
Glycine
65.96
73.68
4.46 0.0128
Alanine
79.35
83.81
4.78 0.1572
Proline
82.45
85.98
1.81 0.0170
Tyrosine
86.93
87.84
1.08 0.2246

17. Results
• Protease improvement on Total Apparent AA
Digestibility of Corn
120%
Mean = 3.4% improvement
115%
*
110%
*
105%
*
*
*
*
*
* = P≤0.10
* *
Le
u
Ph
e
Ly
s
Ile
G
lu
Se
r
G
ly
H
is
A
rg
Th
r
A
la
Pr
o
Ty
r
Va
l
M
et
C
ys
100%
A
sp
Improvement (% Control)
– All Amino Acids

18. Results
True AA digestibility
CP
Lys
Met
Cis
Thr
Arg
Ile
Leu
Val
His
Phe
Lemme, 2004
90
92
94
87
85
93
95
94
92
95
94
Rostagno, 2005
87
85,9
92,3
87,9
83,8
92
90,6
95,4
88,2
93,3
91,5
Total Apparent AA digestibility
Corn
83,05
87,80
87,30
75,01
72,16
81,45
82,33
88,33
81,41
85,52
87,08
Corn + Protease
83,58
88,02
87,48
79,19
79,29
83,56
85,22
89,48
84,71
86,02
88,14

19. Conclusion
• Using 200 ppm of RONOZYME® ProAct
effectively increased utilization of amino acids
in Corn on an average of 3.18%.

20. Acknowledgment
• UFLA
• NECTA
• DSM Nutritional Products

21. Visit DSM at:
• DSM Animal Nutrition and Health