Enzyme-treated soy protein in broiler starter feed goes beyond improving dietary protein digestibility

calendar icon 1 September 2021
clock icon 5 minute read

In the present trial, performance results showed no significant difference in body weight gain between the two dietary treatments. However, replacing part of SBM in starter diets by 5% ESP, numerically improved body weight gain until market age by 31 and 51 grams at day 42 or day 56, respectively, compared with the supplementation of exogenous protease throughout the entire production cycle (Figure 2). Furthermore, mortality adjusted FCR of ESP-supplemented birds was significantly improved by 3, 4 and 3 points at day 35, 42 and 56, respectively, compared with protease-supplemented birds (Figure 3a). Likewise, fixed BW adjusted FCR was significantly improved by 2 and 4 points at day 35 and 42, respectively, compared with the exogenous protease (Figure 3b). At day 56, fixed BW adjusted FCR was numerically improved by 4 points by replacing part of SBM by 5% ESP in the starter diet. Thus, replacing part of SBM by 5% ESP in starter diets to broiler chickens results in market age performance better than the performance of broilers fed a diet supplemented with exogenous protease throughout the production cycle. This is attributed to the reduced ANF content in the starter diet by the inclusion of ESP since the negative effects of high SBM inclusion levels are not only due to the digestibility but also the content of ANFs. To overcome these challenges, the ANF levels must be reduced below the tolerance threshold in the finished feed. As shown in Figure 1, this is not done by adding exogenous proteases in the feed, but by including a high-quality protein source low in ANFs in the diet thereby reducing the inclusion level of SBM.

The problem of soybean ANFs is not solved with proteases since it goes beyond the digestibility of the protein. Results show that it is crucial to reduce the content of ANFs, particularly in starter diets. Chicken performance was improved in the entire production cycle in a cost-efficient way by replacing part of SBM by 5% ESP in the starter diet, without increasing the cost of grower and finisher feed, suggesting a carry-over effect. This is not achieved with proteases, but by using clean protein sources of ANFs, like enzyme-treated soy protein.

Figure 1 Content of soy-delivered anti-nutritional factors (ANF) in starter diets for broiler chickens.
Figure 1 Content of soy-delivered anti-nutritional factors (ANF) in starter diets for broiler chickens.

In the present trial, performance results showed no significant difference in body weight gain between the two dietary treatments. However, replacing part of SBM in starter diets by 5% ESP, numerically improved body weight gain until market age by 31 and 51 grams at day 42 or day 56, respectively, compared with the supplementation of exogenous protease throughout the entire production cycle (Figure 2). Furthermore, mortality adjusted FCR of ESP-supplemented birds was significantly improved by 3, 4 and 3 points at day 35, 42 and 56, respectively, compared with protease-supplemented birds (Figure 3a). Likewise, fixed BW adjusted FCR was significantly improved by 2 and 4 points at day 35 and 42, respectively, compared with the exogenous protease (Figure 3b). At day 56, fixed BW adjusted FCR was numerically improved by 4 points by replacing part of SBM by 5% ESP in the starter diet. Thus, replacing part of SBM by 5% ESP in starter diets to broiler chickens results in market age performance better than the performance of broilers fed a diet supplemented with exogenous protease throughout the production cycle. This is attributed to the reduced ANF content in the starter diet by the inclusion of ESP since the negative effects of high SBM inclusion levels are not only due to the digestibility but also the content of ANFs. To overcome these challenges, the ANF levels must be reduced below the tolerance threshold in the finished feed. As shown in Figure 1, this is not done by adding exogenous proteases in the feed, but by including a high-quality protein source low in ANFs in the diet thereby reducing the inclusion level of SBM.

The problem of soybean ANFs is not solved with proteases since it goes beyond the digestibility of the protein. Results show that it is crucial to reduce the content of ANFs, particularly in starter diets. Chicken performance was improved in the entire production cycle in a cost-efficient way by replacing part of SBM by 5% ESP in the starter diet, without increasing the cost of grower and finisher feed, suggesting a carry-over effect. This is not achieved with proteases, but by using clean protein sources of ANFs, like enzyme-treated soy protein.

Figure 2 Body weight gain (BWG; kg/bird) of broiler chickens fed enzyme-treated soy protein (ESP) day 0-14 compared to exogenous protease fed day 0-56 (SBM+protease).
Figure 2 Body weight gain (BWG; kg/bird) of broiler chickens fed enzyme-treated soy protein (ESP) day 0-14 compared to exogenous protease fed day 0-56 (SBM+protease).
Figure 3 a) Mortality adjusted feed conversion ratio (FCR) and b) fixed BW adjusted FCR of broiler chickens fed enzyme-treated soy protein (ESP) day 0-14 compared to exogenous protease fed day 0-56 (SBM+protease).
Figure 3 a) Mortality adjusted feed conversion ratio (FCR) and b) fixed BW adjusted FCR of broiler chickens fed enzyme-treated soy protein (ESP) day 0-14 compared to exogenous protease fed day 0-56 (SBM+protease).
References
References
Blanch A. (2020a). Soy trypsin inhibitors do affect the growth and gut health of chickens. https://www.thepoultrysite.com/articles/soy-trypsin-inhibitors-do-affect-the-growth-and-gut-health-of-chickens
Blanch A. (2020b). Soy oligosaccharides and beta-conglycinin, behind gut inflammations, wet droppings and footpad dermatitis in chickens. https://www.thepoultrysite.com/articles/soy-oligosaccharides-and-beta-conglycinin-behind-gut-inflammations-wet-droppings-and-footpad-dermatitis--n-chickens
Brown K. (2021). Utilizing a consistent protein ingredient in poultry dietary formulations. https://www.thepoultrysite.com/articles/utilizing-a-consistent-protein-ingredient-in-poultry-dietary-formulations
García-Rebollar, P.; Cámara, L.; Lázaro, R. P.; Dapoza, C.; Pérez-Maldonado, R.; Mateos, G. G., 2016: Influence of the origin of the beans on the chemical composition and nutritive value of commercial soybean meals. Animal Feed Science and Technology., 221, 245–261.
Grieshop, C. M.; Kadzere, C. T.; Clapper, G. M.; Flickinger, E. A.; Bauer, L. L.; Frazier, R. L.; Fahey, G. C., 2003: Chemical and nutritional characteristics of United States soybeans and soybean meals. Journal of Agricultural and Food Chemistry., 51, 7684–7691.
Jiang, H. Q.; Gong, L. M.; Ma, Y. X.; He, Y. H.; Li, D. F.; Zhai, H. X., 2006: Effect of stachyose supplementation on growth performance, nutrient digestibility and caecal fermentation characteristics in broilers. British Poultry Science., 47, 516–522.
Olukosi, O. A.; Beeson, L. A.; Englyst, K.; Romero, L. F., 2015: Effects of exogenous proteases without or with carbohydrases on nutrient digestibility and disappearance of non-starch polysaccharides in broiler chickens. Poultry Science., 94, 2662–2669.
Palacios, M. F.; Easter, R. A.; Soltwedel, K. T.; Parsons, C. M.; Douglas, M. W.; Hymowitz, T.; Pettigrew, J. E., 2004: Effect of soybean variety and processing on growth performance of young chicks and pigs. Journal of Animal Science., 82, 1108–1114.
Rasmussen, S.; Blanch, A.; Davis, A. J.; Brøkner, C., 2021: Growth performance of broiler chickens fed enzyme-treated soy protein day 0-14 compared to exogenous protease fed day 0-56. 2021 Virtual International Poultry Scientific Forum Abstracts., p. P52.
Stefanello, C.; Vieira, S. L.; Rios, H. V.; Simões, C. T.; Sorbara, J. O. B., 2016: Energy and nutrient utilisation of broilers fed soybean meal from two different Brazilian production areas with an exogenous protease. Animal Feed Science and Technology., 221, 267–273.
Thakur, M.; Hurburgh, C. R., 2007: Quality of US soybean meal compared to the quality of soybean meal from other origins. Journal of the American Oil Chemists’ Society., 84, 835–843.

Alfred Blanch

Poultry Category Manager at Hamlet Protein A/S (Horsens, Denmark).

Simone Husballe Rasmussen

Hamlet Protein
© 2000 - 2024 - Global Ag Media. All Rights Reserved | No part of this site may be reproduced without permission.