A CLOSER LOOK AT THE EFFICACY OF MODIFIED GH11 XYLANASE FOR BROILERS
Dr. Koushik De
Sales Director, Poultry-SCA, NOVUS
In India, most broiler diets rely heavily on corn and soybean meal, with corn often making up two-thirds of the formulation. While these ingredients offer significant energy and protein, broilers face physiological limitations: Due to gastrointestinal limitations and minimal endogenous enzyme production, broilers lack the digestive capacity to utilize the full nutritive value of their diet. As a result, a substantial portion of feed energy passes through undigested, wasting resources and leaving performance gains unrealized. In an effort to maximize nutrient utilization, Exogenous enzymes, particularly xylanases, are used to break down these indigestible compounds, especially non-starch polysaccharides (NSPs). But corn poses unique challenges due to its high inclusion rate and the nature of its NSP content.
Although corn has a lower total NSP content than soybean meal, its impact is high because of how much corn is used in the diet. Even in well-balanced corn-soy diets, NSPs like arabinoxylans, β-glucans, mannans, and galactomannans can impede nutrient absorption and energy utilization in the digestive tract, reducing overall broiler performance. These anti-nutritional effects can result in the loss of up to 400–450 kcal/kg of energy, primarily from fat, protein, and starch (1). For producers operating on tight margins, this hidden inefficiency can quietly erode both performance and profitability.
The impact of xylanase in wheat-based diets has been widely explored and has shown consistent results (2). But when it comes to corn and other non-viscous grains which have a presence of more insoluble xylans, there has been skepticism among nutritionists and producers about the role and efficacy of xylanase.
Understanding GH11 Xylanase
Feed represents the single largest cost in poultry production, accounting for up to 70% of total costs. As a result, reducing feed costs without compromising performance remains a top priority for the industry. Xylanase is one effective way to achieve lower feed costs by reducing viscosity and releasing nutrients.
While standard GH10 xylanases perform well in wheat and rye by reducing viscosity, their effect is often limited in corn-based diets. However, GH11 xylanases are structurally different from their GH10 counterparts. The GH11 xylanase consists of a single catalytic module and degrades both soluble and insoluble xylans. Typically, the GH11 family of xylanase is more active than GH10 on insoluble substrate and thereby allows more entrapped nutrients to be released in corn-soy diets.
Because GH11 acts on both soluble and insoluble fractions, it has opened new possibilities for unlocking energy previously lost in broiler diets dominated by corn.
Enhancing the GH11 Advantage
Recognizing the potential of GH11 enzymes in corn-soy diets, NOVUS has introduced a modified GH11 xylanase with enhanced efficacy as part of its CIBENZA® Enzyme Feed Additive range. This endo-1,4-beta-xylanase, derived from a unique gene in a naturally occurring fungal microorganism, features a starch binding domain as a secondary binding site for greater catalytic activity, supports degrading of both soluble and insoluble xylans and offers consistent results. (Figure 1)
Its thermostability, low-pH resistance, and pump-like structure help ensure the enzyme performs reliably across feed manufacturing and in vivo conditions. Unlike traditional GH10 enzymes, this modified GH11 xylanase was specifically optimized through trials using corn-based diets, making it a better fit for markets like India.
Figure 1: Evolution of Xylanase Technology
Time matters when it comes to enzyme activity in poultry digestion. With a relatively short feed retention time in the lower digestive tract, enzyme efficiency is critical for nutrient release. A comparative analysis of different xylanases (Figure 2) shows that the commercial
GH10 degraded 10% of the insoluble xylans in five hours and commercial GH11 degraded 20% of the insoluble xylans in five hours. Whereas NOVUS modified GH11 xylanase degraded 20% of the insoluble xylans in one hour. This rapid hydrolysis of insoluble xylans highlights the aggressive mode of action and superior suitability of NOVUS’ enzyme for corn-soy diets, where fast and consistent NSP breakdown is essential for optimal nutrient release.
Figure 2: Comparative Degradation of Insoluble Xylans by Xylanase Enzymes (Corn, Rice Bran, Sorghum Substrates)
Source: BRI (A NOVUS Subsidiary) Internal Study
Broiler Performance Improvement
NOVUS recently completed a performance trial in India in 2024 to further evaluate its modified GH11 xylanase, under local production conditions In this study, 432 Cobb broilers were fed a corn–soybean meal (SBM) diet with 130 kcal/kg reduced metabolizable energy (ME) over a 42-day period. Birds received either a modified GH11 xylanase at 100 gram/kg feed inclusion or a standard GH11 xylanase at the same inclusion level. This trial was designed to reflect practical field conditions while testing enzyme effectiveness in unlocking energy from NSPs in corn-heavy formulations common to the region.
Broilers supplemented with modified GH11 xylanase achieved better performance outcomes at 42 days compared to those fed a standard GH11 xylanase. Birds receiving modified GH11 xylanase showed higher body weights (BW) and lower feed conversion ratios (FCR), even when the diet was formulated to include 130 kcal/kg less metabolizable energy (ME). (Figure 3,4). At just 100 gram/kg feed inclusion, the enzyme helped offset the effects of reduced energy, delivering more consistent performance and can enhance the overall return on investment in corn-soy based feeding programs.
Figure 3: Body Weight Gain at 42 Day
Figure 4: Corrected FCR (Same Body Weight) at 42 Day
Advancing Feed Efficiency Through Modified GH11 Xylanase Technology
Not all xylanases are the same, especially when it comes to efficiency in corn. For poultry producers working to reduce feed costs without compromising bird performance, enzyme solutions must match the nutritional realities of their diets.
By efficiently breaking down NSPs and improving nutrient availability, NOVUS’s Modified GH11 Xylanase Enzyme Feed Additive offers a modern approach to feed optimization in corn-soy diet. This results in a better feed conversion ratio, more consistent performance, and improved ROI.
References:
1. Cowieson, A. J. 2010. Strategic selection of exogenous enzymes for corn/soy-based poultry diets. The Journal of Poultry Science 47:1–7.
2. Brad Gorenz, Vanessa Iseri, Jon Rubach, Ryan N. Dilger, Xylanase supplementation of pelleted wheat-based diets increases growth efficiency and apparent metabolizable energy and decreases viscosity of intestinal contents in broilers, Poultry Science, Volume 101, Issue 12, 2022,
3. Biely P, Singh S, Puchart V. Towards enzymatic breakdown of complex plant Xylan structures: state of the art. Biotech Adv. (2016) 34:1260– 74. doi: 0.1016/j.biotechadv.2016.09.001
4. Snelders J, Olaerts H, Dornez E, van de Wiele T, Aura A-M, Vanhaecke L, et al. Structural features and feruloylation modulate the fermentability and evolution of antioxidant properties of arabino xylo oligosaccharides during in vitro fermentation by human gut derived microbiota. J Funct Foods. (2014) 10:1–12. doi: 10.1016/j.jff.2014.05.011