into a Crown desolventizer/toaster with three decks (top, middle, and bottom) set for a meal depth of 3-5 inches with a product discharge temperature of 110C.
Effect of soybean processing condition and enzyme supplementation on growth performance of broilers fed corn/soy-based diets A.M. Amerah, L.F. Romerao and K. Okasha
Abstract The aim of the present experiment was to examine the effect of soybean processing conditions and a combination of exogenous xylanase, amylase and protease (XAP) on the performance and carcass characteristics of broilers fed corn/soybean meal-based diets. The experimental design was a 3 x 2 factorial arrangement of treatments evaluating 3 soybean processing conditions (normal cook (SBM1), extended cook time (SBM2) and shortened cook time (SBM3)) and two levels of enzyme supplementation (without or with XAP, to provide 2000 U of X, 200 U of A, and 4000 U of P/kg diet (Axtra XAP, Danisco Animal Nutrition). Single source of soybean was used to produce the 3 tested SBM. Each diet was fed ad libitum to 8 pens of 40 male broilers, each from day 1 to 49. Data were subjected to two-way ANOVA and means were separated by Student’s test. Soybean processing condition and enzyme supplementation had no effect (P>0.05) on weight gain, feed intake and carcass characteristics. Enzyme supplementation improved (P0.05) were observed for any of the measured parameters at any period. In conclusion, under the conditions of this study, SBM processing had no effect on broiler performance. The combination of xylanase, amylase and protease improved feed conversion ratio regardless of the SBM processing condition tested in this study. Soybean processing, enzymes, broilers, performance
Introduction Soybean meal (SBM) is the predominant vegetable protein used in broiler diets worldwide due to its excellent amino acid profile. Before inclusion in broiler diets, ssoybean is usually processed. The main objectives of the processing are to extract oil and to eliminate the anti-nutritional components such as trypsin inhibitors (Ward, 1996). However, variation in processing conditions may results in variation in SBM quality
(Batal et al., 2000). Unless proper heat treatment is applied, SBM can be either undercooked (higher trypsin inhibitor level) or overcooked (lower protein quality). Multi-enzyme products have been used in broiler diets to improve performance, nutrient digestibility and minimize variation in ingredient quality (Tang et al., 2014). Studies examining the effect of enzymes on broiler performance fed SBM processed under different conditions are limited. Therefore, the objective of this study was to examine the effect of soybean processing conditions and a combination of exogenous xylanase, amylase and protease (XAP) on the performance and carcass characteristics of broilers fed corn/soybean meal-based diets. Materials and methods Single source of whole soybean was sourced, cracked and de-oiled using hexane extraction. To remove residual hexane and yield toasted meal, the marc was fed directly into a Crown desolventizer/toaster with three decks (top, middle, and bottom) set for a meal depth of 3-5 inches with a product discharge temperature of 110C. To achieve the normal cook, the marc was held on the top deck at 65C, the second deck at 100C, with normal conditions on the third deck as stated above. To achieve shortened cook time, marc was not retained on the top deck, but did most of the desolventization on the second deck, which was held at 85 to 100C, and normal discharge conditions as noted above for the third deck. For the extended cook time, marc was desolventized on the top deck with high sparge steam, and a temperature of 75C. On the second deck the meal was moisturized to approximately 25% and held at 100C, followed by normal conditions on the third deck. The retention time for marc in the DT was approximately 30 minutes. Diets based on corn and one of the SMBs were formulated and fed over 3 phases. All diets contained phytase (500 FTU/kg) which was assumed to contribute Av P 0.146 and Ca 0.134. Each diet was fed ad libitum to 8 pens of 40 male broilers (Ross 708), each from day 1 to 49. Data were subjected to two-way ANOVA and means were separated by Student’s test.
Results and discussion Processing conditions resulted in 3 levels of trypsin inhibitor and protein dispersibility index (5200, 3700 and 8000 TIU/g; 22.6, 19.9 and 24.1% for SBM1, SBM2 and SBM3, respectively). The effect of soybean meal processing and enzyme supplementation on broiler performance is summarized in Table 1. Soybean processing condition had no effect (P>0.05) on broiler performance and carcass characteristics. These results suggest that the difference in SBM due to processing conditions was not large enough to induce difference in broiler performance. Enzyme supplementation had no effect (P>0.05) on weight gain, feed intake and carcass characteristics, but improved (P0.05) were observed for any of the measured parameters at any period. In conclusion, under the conditions of this study, SBM processing had no effect on broiler performance. The combination of xylanase, amylase and protease improved feed conversion ratio regardless of the SBM processing condition tested in this study.
Table 1. Effect of soybean meal processing and enzyme supplementation on broiler performance and carcass characteristics (% of bodyweight) fed corn-soy based diets (049 days) 1 Treatment SBM SBM1 SBM2 SBM3 SEM Enzyme No enzyme XAP SEM P-value SBM Enzyme SBM x Enzyme 1 2
Weight gain (g/bird)
Feed intake (g/bird)
FCR (g/g)
2863 2855 2864 8
5579 5566 5570 22
1.940 1.945 1.939 0.005
70.5 71.4 71.4 0.35
17.7 17.5 17.5 0.64
2845 2877 11
5570 5570 20
1.952 1.931 0.007
71.1 71.1 0.22
17.8 17.4 0.41
0.87 0.05 0.60
0.96 0.96 0.99
0.90 0.04 0.65
0.49 0.90 0.42
0.90 0.15 0.75
Each value represents the mean of 8 replicates (8 birds per replicate). Pooled standard error of the mean.
Carcass weight Breast meat (%) (%)
References Batal, A. B., M. W. Douglas, A. E. Engram, and C. M. Parsons. 2000. Protein dispersibility index as an indicator of adequately processed soybean meal. Poult. Sci. 79:1592–1596. Romero, L. Medel P., Sánchez, J. and M. I. Gracia. 2011. Effect of an enzyme blend supplementation on performance of broiler chickens fed wheat based diets. Annual Meeting Abstracts – Poult. Sci. Vol. 90 (E-suppl. 1) p. 141. Tang, D., S. Hao, G. Liu, F. Nian, and Y. Ru. 2014. Effects of maize source and complex enzymes on performance and nutrient utilization of broilers. Asian-Aust. J. Anim. Sci. 27:1755–1762. Ward, N. E. 1996. Quality considerations for soybean meal. ASA Technical Bulletin. MITA No. 195, 11. ASA, Singapore.
