CONCLUSIONIn this study, protease supplementation was effective in improving thestandardized ileal digestibility of almost all the amino acids in wheatmiddlings.

Improvement of SIAAD in the presence of protease is not the same for all AA and varies from one ingredient to another one. Theeffects of added protease are dependent on feed composition and on intrinsic digestibility of AA (COWIESON and ROOS (2014)).Factors such as type and quality of the ingredients, industrial processing and the presence of anti-nutritional substances such astannins, phytates, trypsin inhibitors in plant species modulate the digestibility in poultry feed and thus the effectiveness ofexogenous protease.The physiological state of animals (growth or maintenance), feed consumption or the nutritional feed quality could also influencethe digestibility values.

MATERIALS & METHODSAnimals: 6 x 8 male broilers (Ross PM3) / treatmentDiets: Diet 1 was Nitrogen-free diet (NFD) to be used for estimating endogenous nitrogen and amino acids losses Diets 2 and 3 were experimental diets in which wheat by product DDGS and wheat middlings was the onlysource of dietary protein included at 94.5 %Diets 5 and 6 were the same as diets 2 and 3, with the protease Ronozyme® ProAct added at 15000 PROT/kg Feeding: mash, ad libitumDuration: day 20 to day 24 of bird ageParameters: standardized ileal amino acid digestibility (SIAAD) calculated using the formula given by LEMME et al.(2004)Statistical analysis: ANOVA followed by Newman-Keuls test (p<0.05)

Effects of protease supplementation on the standardized ileal amino acid digestibility in two wheat by-products in

broiler chickensR. Aureli1, P.Guggenbuhl1 and J. Broz2

1Research Centre for Animal Nutrition and Health, DSM Nutritional Products France, Saint Louis, France, 2DSM Nutritional Products Ltd, Basel, Switzerland

OBJECTIVEKnowledge of amino acid (AA) digestibility of feed ingredients is necessary to feed broilers withproperly balanced compound diets. For this reason, more attention has recently been given to thedetermination of AA digestibility of ingredients, recognizing that it may vary greatly dependingupon the feed ingredient. The effects of the inclusion of a mono-component serine protease(Ronozyme® ProAct) on standardized ileal amino acid digestibility (SIAAD) of diets containing wheatby-products (wheat DDGS (WDDGS) and wheat middlings (WM)) were evaluated in broilers.

OBJECTIVEKnowledge of amino acid (AA) digestibility of feed ingredients is necessary to feed broilers withproperly balanced compound diets. For this reason, more attention has recently been given to thedetermination of AA digestibility of ingredients, recognizing that it may vary greatly dependingupon the feed ingredient. The effects of the inclusion of a mono-component serine protease(Ronozyme® ProAct) on standardized ileal amino acid digestibility (SIAAD) of diets containing wheatby-products (wheat DDGS (WDDGS) and wheat middlings (WM)) were evaluated in broilers.

RESULTS & DISCUSSION

20th European Symposium on Poultry Nutrition ,24–27 August 2015 , Prague

SIAAD (%)Enzyme1

- + - +WM p= SEM WDDGS p= SEM

EAAs2

Arg 81.5 82.2 0.684 0.27 72.1 72.9 0.516 0.24His 74.9 80.9 0.007 0.35 88.0 87.3 0.197 0.16Ile 77.5 79.9 0.293 0.32 67.8 65.8 0.239 0.28Leu 81.3 82.4 0.449 0.26 78.1 78.8 0.490 0.21Lys 80.2 78.1 0.292 0.31 73.0 74.5 0.409 0.28Met 83.4 83.4 0.945 0.24 74.2 75.2 0.490 0.25Phe 81.4 83.5 0.142 0.26 83.3 83.4 0.990 0.19Thr 68.9 71.3 0.272 0.31 65.4 68.6 0.115 0.31Val 78.2 78.9 0.743 0.30 70.0 72.6 0.175 0.30

NEAAs3

Ala 74.8 76.4 0.358 0.28 67.6 65.5 0.178 0.27Asp 73.5 76.0 0.177 0.29 47.7 42.7 0.053 0.36Cys 75.2 74.8 0.809 0.28 67.9 68.7 0.707 0.31Glu 88.7 89.6 0.314 0.21 85.0 83.7 0.129 0.20Gly 85.6 90.3 0.058 0.35 60.4 52.7 0.068 0.45Pro 86.2 86.9 0.410 0.20 84.4 84.5 0.869 0.19Ser 76.8 75.8 0.752 0.38 72.7 72.7 0.990 0.23Tyr 79.2 80.7 0.278 0.31 79.6 79.8 0.898 0.26

1 - No added enzyme, + Added enzyme (Ronozyme® ProAct at 15000 PROT/kg); 2EAAs: essential amino acids; 3NEAAs: non-essential amino acids

Figure 1: Efficacy of protease in improving SIAAD in broiler chickens fed experimental diets for wheat middlings and wheat DDGS

ReferencesCOWIESON A.J, ROOS F. F., 2014: Bioefficacy of a mono-component protease in the diets of pigs and poultry: a meta-analysis of effect on ileal amino aciddigestibility. J.Appl Ani.Nut. 2, 1-8LEMME, A., V. RAVINDRAN, W. L. BRYDEN, 2004: Ileal digestibility of amino acid in feed ingredients for broilers. World’s Poult. Sci. J.60, 423-437

Table 1: Ileal standardized ileal digestibility coefficients (%) of amino acids (SIAAD) for broilers fed experimental diets