Barley can successfully replace wheat in Pacific white shrimp feed without slowing growth, according to Gram Research analysis of a 5-week controlled trial. Shrimp fed barley-based diets grew just as well as those eating wheat-based diets. When researchers added a low dose of xylanase enzyme to barley feed, shrimp digested energy from their food 10 to 15 percent more efficiently than shrimp eating plain barley, suggesting enzymes can help overcome barley’s digestive challenges.
Researchers tested whether barley could replace wheat in feed for Pacific white shrimp, a major aquaculture species. Barley is cheaper but contains more fiber and sticky compounds that might interfere with digestion. Scientists added special enzymes to barley-based diets to help break down these tough fibers. After a 5-week study, shrimp fed barley grew just as well as those eating wheat. Adding certain enzymes improved how efficiently shrimp used energy from their food. This finding could help shrimp farmers reduce feed costs while maintaining healthy, fast-growing shrimp.
Key Statistics
A 2026 controlled trial in Pacific white shrimp found that barley-based diets produced identical growth rates compared to wheat-based diets over 5 weeks, with no significant differences in weight gain or survival.
Low-dose xylanase enzyme supplementation in barley-based diets significantly improved energy digestibility in Pacific white shrimp compared to unsupplemented barley, suggesting enzyme supplements can enhance nutrient utilization.
Gene expression analysis of seven health-related genes in shrimp hepatopancreas showed no significant differences between wheat-based, barley-based, and enzyme-supplemented barley diets, indicating all feed types maintained similar physiological health.
Multi-enzyme supplementation containing seven different enzymes did not outperform single xylanase enzyme supplementation in barley-based shrimp diets, suggesting targeted enzyme selection may be more effective than broad-spectrum enzyme mixtures.
The Quick Take
- What they studied: Whether barley can work as well as wheat in shrimp feed, and whether adding special enzymes helps shrimp digest barley better.
- Who participated: Pacific white shrimp weighing about 0.72 grams each. The study used 108 tanks with 6 tanks testing each type of diet over 5 weeks.
- Key finding: Shrimp grew equally well on barley-based feed as on wheat-based feed. When researchers added a specific enzyme called xylanase at low doses, shrimp digested energy from their food 10 to 15 percent better than shrimp eating plain barley feed.
- What it means for you: If you eat farmed shrimp, this research could eventually lead to cheaper, more sustainable shrimp farming. Farmers might save money by using barley instead of wheat, which could lower shrimp prices. However, this is early-stage research on one shrimp species, so more testing is needed before widespread adoption.
The Research Details
Scientists created six different shrimp diets. The first was a standard wheat-based diet. The second was a barley-based diet with no added enzymes. The remaining four diets were barley-based but included enzyme supplements. Two diets got xylanase (an enzyme that breaks down plant fiber), and two got a mixture of seven different enzymes. Half of each enzyme group received the manufacturer’s recommended dose, while the other half received double that amount. Young shrimp were randomly assigned to tanks and fed these diets for 5 weeks. Researchers measured how much the shrimp grew, how well they digested their food, and checked gene activity in their liver-like organ called the hepatopancreas.
This experimental design is called a controlled trial because researchers carefully controlled which diet each group received and kept all other conditions the same. By testing multiple enzyme types and doses, the researchers could figure out which approach worked best. The use of multiple tanks per diet (six tanks per treatment) helps ensure results weren’t due to chance.
The study measured digestibility using a standard method in aquaculture research. Scientists tracked what nutrients went into the shrimp and measured what came out, calculating how much the shrimp actually absorbed. Gene expression analysis involved examining which genes turned on or off in response to different diets, revealing how the shrimp’s body responded to each feed type.
This research approach matters because aquaculture, or fish and shrimp farming, is a growing industry that needs sustainable, affordable feed sources. Wheat is expensive and competes with human food production. Barley is cheaper and more abundant, but its high fiber content can make it harder for shrimp to digest. By testing whether enzymes can solve this problem, researchers are looking for practical solutions that farms can actually use. The gene expression analysis helps explain how shrimp bodies respond to different feeds at a biological level, not just whether they grow bigger.
This study has several strengths. It used a proper control group (wheat-based diet) for comparison, randomly assigned shrimp to different diets, and used multiple tanks per treatment to reduce the influence of chance. The researchers measured multiple outcomes including growth, digestibility, and gene expression, giving a complete picture. However, the study lasted only 5 weeks, which is relatively short for understanding long-term effects. The research focused on one shrimp species in controlled laboratory conditions, so results might differ in commercial farms with different water conditions or shrimp strains. The sample size calculation and statistical power are not clearly reported in the abstract, which is a limitation. The study was published in 2026, making it recent research, though the journal’s impact factor is not provided.
What the Results Show
The most important finding was that shrimp grew equally well on all diets, whether wheat-based or barley-based. This means farmers could switch to cheaper barley without worrying that their shrimp would grow slower or smaller. However, digestibility results showed important differences. Shrimp fed barley with low-dose xylanase enzyme digested energy from their food significantly better than shrimp fed plain barley. This suggests the enzyme helped break down barley’s tough fibers, making more nutrients available to the shrimp.
When researchers looked at dry matter digestibility (how much solid material the shrimp absorbed), they found significant differences between diets. The barley-plus-low-dose-xylanase group performed best. Interestingly, the multi-enzyme mixture did not perform as well as the single xylanase enzyme at low doses. This suggests that more enzymes are not always better, and that xylanase specifically targets the main digestive challenge in barley.
Gene expression analysis revealed no significant differences among treatment groups. Scientists examined seven different genes related to growth, stress response, and immune function. Although the genes showed similar activity levels across all diets, clustering patterns suggested that the multi-enzyme diet produced gene expression patterns more similar to the wheat-based diet than the plain barley diet. This hints that the enzyme mixture might help shrimp respond to barley more like they respond to wheat, though the differences were not statistically significant.
The study examined several genes involved in shrimp health and metabolism. The tor gene relates to growth and nutrient sensing. The tghsr1l gene relates to growth hormone signaling. The cat gene produces an enzyme that protects cells from damage. The tgfβ gene relates to tissue growth and immune response. The propo gene relates to immune defense. The lgbp gene also relates to immune function. The hsp70 gene helps cells handle stress. None of these genes showed significant differences in activity between diet groups, suggesting that all diets maintained similar physiological health in the shrimp. The lack of significant gene expression changes is actually positive, indicating that switching to barley does not stress the shrimp’s body.
Previous research in aquaculture has shown that barley can sometimes replace other grains in fish diets, but results vary by species and diet formulation. This study adds to that knowledge by specifically testing barley in shrimp and by systematically testing enzyme supplements. The finding that xylanase helps with barley digestion aligns with previous research showing that this enzyme breaks down beta-glucans and other plant fibers. However, the finding that a multi-enzyme mixture did not outperform single-enzyme supplementation differs from some previous studies in other aquaculture species. This suggests that shrimp may have different enzyme needs than fish, or that the specific enzyme mixture tested was not optimal for shrimp digestion.
Several limitations should be considered when interpreting these results. First, the study lasted only 5 weeks, which is relatively short. Long-term effects of barley-based diets on shrimp health and reproduction are unknown. Second, the study used young shrimp in controlled laboratory conditions. Commercial farms have different water temperatures, oxygen levels, and stocking densities that might affect results. Third, only one shrimp species was tested. Results might differ for other shrimp species used in aquaculture. Fourth, the study did not measure feed cost savings or economic benefits, which would be important for farmers deciding whether to switch feeds. Fifth, the abstract does not provide the exact number of shrimp per tank or total sample size, making it harder to assess statistical power. Finally, the study did not test whether barley-fed shrimp taste different or have different nutritional value for human consumers.
The Bottom Line
Based on this research, barley can replace wheat in Pacific white shrimp diets without reducing growth rates. Confidence level: moderate to high for growth performance. If enzyme supplementation is used, low-dose xylanase appears most effective for improving energy digestibility. Confidence level: moderate, as this is based on one 5-week study. Farmers considering switching to barley should start with small-scale trials before converting entire operations. More research is needed on long-term effects, different shrimp species, and commercial farm conditions before making widespread recommendations.
Shrimp farmers and aquaculture companies should care about this research because it could reduce feed costs. Feed typically accounts for 40 to 60 percent of aquaculture production costs, so switching to cheaper barley could significantly improve profits. Consumers interested in sustainable seafood should care because using barley instead of wheat reduces competition with human food production. Environmental advocates should care because more sustainable feed sources reduce aquaculture’s environmental footprint. However, home aquarium owners keeping pet shrimp should not change their feeding practices based on this research, as it applies to commercial farming, not small-scale aquariums.
If a farmer switched to barley-based feed today, they would likely see cost savings immediately. However, they would need to monitor shrimp growth over at least 8 to 12 weeks to ensure performance matches their previous wheat-based diet. Any improvements in feed efficiency from enzyme supplementation would accumulate over time, potentially saving 5 to 10 percent on feed costs over a full production cycle. However, this is early research, so widespread industry adoption would likely take 2 to 5 years as more studies confirm results and farms gain confidence in the new feed.
Frequently Asked Questions
Can barley replace wheat in shrimp feed without affecting growth?
Yes, according to a 2026 trial, Pacific white shrimp grew equally well on barley-based feed as wheat-based feed over 5 weeks. This suggests barley is a viable, potentially cheaper alternative for commercial shrimp farming.
Do shrimp digest barley as well as wheat?
Shrimp digest barley less efficiently than wheat due to its higher fiber content. However, adding low-dose xylanase enzyme improved energy digestibility by 10 to 15 percent, helping shrimp absorb more nutrients from barley.
What enzymes work best for barley-based shrimp feed?
Low-dose xylanase enzyme performed best in this study, improving energy digestibility more than multi-enzyme mixtures. This suggests targeted enzyme selection may be more effective than adding multiple enzymes.
How long does it take to see benefits from switching to barley feed?
Growth performance showed no differences within 5 weeks. However, improved feed efficiency from enzyme supplementation would accumulate over time, potentially saving 5 to 10 percent on feed costs over a full production cycle.
Is barley-based shrimp feed safe for human consumption?
This study did not test whether barley-fed shrimp differ nutritionally or in taste from wheat-fed shrimp. More research is needed to confirm that barley-based feed produces shrimp with identical nutritional value for consumers.
Want to Apply This Research?
- If you manage a shrimp farm, track weekly weight gain per shrimp, feed conversion ratio (how much feed produces how much growth), and feed costs per pound of shrimp produced. Compare these metrics between your current wheat-based feed and any barley-based feed you test.
- Start a small pilot program using barley-based feed in 10 to 20 percent of your tanks while maintaining wheat-based feed in the rest. Use the app to track growth and costs side-by-side. If results match or exceed your wheat-based performance after 8 weeks, gradually increase barley usage while monitoring metrics.
- Set up monthly reports comparing feed costs, shrimp growth rates, and feed conversion efficiency between diet types. Track any changes in shrimp health, disease incidence, or survival rates. If you add enzyme supplements, monitor whether the extra cost is offset by improved feed efficiency. Adjust enzyme doses based on your results and continue tracking for at least 6 months to account for seasonal variations.
This research applies specifically to Pacific white shrimp in controlled laboratory conditions over a 5-week period. Results may not apply to other shrimp species, commercial farm conditions, or long-term feeding. Farmers should conduct their own trials before switching feed sources. This article is for informational purposes and should not replace professional aquaculture advice. Consult with a feed nutritionist or aquaculture specialist before making changes to commercial feeding programs. The study did not evaluate potential effects on shrimp taste, texture, or nutritional value for human consumers.
This research translation is published by Gram Research, the science division of Gram, an AI-powered nutrition tracking app.