Researchers tested whether adding a special enzyme called xylanase to chicken feed could help chickens grow better and stay healthier. They fed 300 baby chickens different diets for six weeks—some with the enzyme, some without, and some with added fiber from wheat or rice. The chickens that got the enzyme converted their food into body weight more efficiently, meaning they needed less food to gain the same amount of weight. The enzyme also helped create more healthy bacteria in their digestive systems and improved how their intestines looked under a microscope. This suggests that xylanase could be a useful, natural way to improve chicken farming.

The Quick Take

  • What they studied: Whether adding a digestive enzyme (xylanase) and fiber sources to chicken feed could improve how well chickens grow and how healthy their digestive systems become
  • Who participated: 300 one-day-old male broiler chickens (the kind raised for meat) divided into 6 different diet groups, with 10 chickens in each small group, studied for 42 days (about 6 weeks)
  • Key finding: Chickens that received the xylanase enzyme needed significantly less food to gain the same amount of weight compared to chickens without the enzyme, especially during the final growth phase. The enzyme also increased beneficial bacteria in their digestive systems.
  • What it means for you: If you raise chickens or work in poultry farming, adding xylanase to wheat-based feed may reduce feed costs while maintaining healthy bird growth. However, this research is specific to chickens and doesn’t directly apply to human nutrition.

The Research Details

Scientists divided 300 baby chickens into 6 groups based on two different factors: whether their feed contained added fiber (none, wheat bran, or rice bran) and whether their feed contained the xylanase enzyme. Each group had 50 chickens split into 5 smaller groups of 10 birds. All chickens were raised under identical conditions for 42 days, and researchers measured how much they ate, how much weight they gained, and what their digestive systems looked like.

This type of study is called a ‘factorial design,’ which means researchers tested two things at the same time to see if they work better together or separately. By keeping everything else the same (temperature, light, housing), the scientists could be confident that any differences they saw were caused by the feed changes, not other factors.

The researchers measured several important things: how much food the chickens ate, how much weight they gained, how efficiently they converted food into body weight, what kinds of bacteria lived in their digestive systems, and what their intestinal tissue looked like under a microscope.

This research approach is important because it tests a real-world farming situation—chickens actually eat wheat-based diets on farms. By testing the enzyme both alone and combined with different fiber sources, scientists could figure out whether the enzyme works better in certain situations. The study also looked at multiple health markers (growth, bacteria, intestinal health) rather than just one thing, giving a more complete picture of whether the enzyme actually helps.

This study was published in Poultry Science, a respected journal in animal agriculture. The researchers used a ‘completely randomized design,’ which is a strong scientific method that helps prevent bias. They tested multiple groups and measured several different outcomes, which strengthens their conclusions. However, the study only looked at one type of chicken breed and one sex (males), so results might differ for other types of chickens or females. The study was conducted in a controlled laboratory setting, which is different from real farm conditions.

What the Results Show

Chickens that received xylanase enzyme needed less food to gain weight, especially during the final 2-3 weeks of growth. This is measured by something called ‘feed conversion ratio’—a lower number means the chicken needs less food to gain one pound of weight. The enzyme improved this ratio by a meaningful amount during both the final growth phase and across the entire 6-week period.

When xylanase was added to diets that already contained fiber (wheat bran or rice bran), chickens ate less overall but still grew well. Interestingly, when the enzyme was added to the basic diet without extra fiber, chickens actually gained slightly less weight, but they still converted their food more efficiently.

The enzyme also changed the bacteria living in the chickens’ digestive systems in positive ways. Specifically, it increased the population of Lactobacillus, which are ‘good bacteria’ that help with digestion and health. The enzyme also made the digestive system more acidic in certain areas, which can help prevent harmful bacteria from growing.

When researchers looked at the chickens’ intestines under a microscope, they found that the enzyme improved the structure of the intestinal lining, particularly in chickens that also received wheat bran. The intestinal lining had taller finger-like projections (called villi) that help absorb nutrients from food.

The enzyme reduced the thickness of digestive fluid in the small intestine, which can help nutrients move through and be absorbed better. However, the enzyme did not affect how wet the bedding in the chicken cages became, suggesting it didn’t cause digestive upset or diarrhea. The combination of xylanase with rice bran produced similar positive effects as the combination with wheat bran, suggesting the enzyme works well with different types of fiber sources.

This research builds on previous studies showing that enzymes can help chickens digest grain-based diets better. The finding that xylanase works especially well when combined with insoluble fiber is relatively new and suggests that fiber and enzymes may work together in the digestive system. Previous research has shown similar benefits with other enzyme types, so this study adds to growing evidence that enzyme supplementation is a practical tool in poultry farming.

This study only tested male broiler chickens, so results might be different for female chickens or other chicken breeds. The research was done in a controlled laboratory setting with carefully managed conditions, which is different from actual farm environments where temperature, humidity, and stress levels vary. The study only lasted 6 weeks, so we don’t know if the benefits would continue longer or if chickens would adapt to the enzyme over time. The researchers didn’t test different amounts of the enzyme, so we don’t know the optimal dose. Finally, this research is specific to chickens and cannot be applied to human nutrition or other animals.

The Bottom Line

For poultry farmers: Consider adding xylanase enzyme to wheat-based chicken feed, especially when combined with insoluble fiber sources like wheat bran or rice bran. This appears to reduce feed costs while maintaining or improving chicken growth and health. The evidence is strong for improved feed efficiency (moderate to high confidence). The benefits for intestinal health are clear in laboratory measurements but may vary in real farm conditions (moderate confidence). Start with small-scale testing before switching all feed supplies.

This research is most relevant to commercial poultry farmers and feed manufacturers who work with wheat-based diets. It may also interest veterinarians who advise on poultry nutrition and researchers studying animal digestion. This research does NOT apply to people eating chicken—it doesn’t tell us anything about the nutritional value of chicken meat or whether eating chicken from enzyme-supplemented birds is different. Pet chicken owners might find it interesting but probably won’t have access to specialized enzyme supplements.

Feed efficiency improvements appeared throughout the 6-week study period, with the biggest benefits showing up during the final 2-3 weeks of growth. Changes in gut bacteria and intestinal structure would likely develop gradually over the first 2-3 weeks. On a real farm, you might expect to see reduced feed costs within the first month of switching to enzyme-supplemented feed.

Want to Apply This Research?

  • If you manage a poultry operation, track weekly feed consumption (in pounds) versus total body weight gain (in pounds) for each flock. Calculate feed conversion ratio weekly: divide total feed consumed by total weight gained. Compare this metric between flocks fed with and without xylanase supplementation over a 6-week period.
  • For poultry farmers: Work with your feed supplier to add xylanase enzyme to your wheat-based feed formulation. Start by supplementing one small flock or pen while keeping another as a control group. Monitor feed intake, growth rates, and bird health daily. Adjust enzyme dosage based on results and cost-benefit analysis.
  • Establish a baseline of your current feed conversion ratio before making changes. After adding xylanase, measure weekly for 6-8 weeks to see if efficiency improves. Track not just growth and feed intake, but also bird health indicators like mortality rate, disease incidence, and litter quality. Keep detailed records to compare costs of enzyme supplementation against savings from reduced feed use.

This research is specific to broiler chickens and does not apply to human nutrition or health. The study was conducted in controlled laboratory conditions and results may differ in real farm environments. Before making changes to poultry feed or management practices, consult with a veterinarian or poultry nutrition specialist. This research should not be used to make medical or health decisions for people. If you have questions about your own diet or health, speak with a healthcare provider or registered dietitian.