Gut Health & Nutrition Library · Technical Article
Tributyrin and Butyrates in Broiler Diets: Trial Evidence, Doses and Feeding Programs
What published broiler trials, two recent meta-analyses and a commercial farm trial actually show about butyrate forms — sodium butyrate, coated sodium butyrate and tributyrin — and how to convert that evidence into inclusion rates, phase programs and realistic expectations.
Author: Shouhui Chen — SKF (Beijing) Biotechnology Co., Ltd. · Last updated: 28 September 2026 · Reading time: ~11 min
Key takeaways
- A 2025 meta-analysis of protected sodium butyrate (17 experiments, 12,204 broilers) found final body weight +40 g, ADG +1.10 g/day, FCR improved by 0.015 units and villus height +9%. [2]
- Butyrate responses are challenge-dependent: a second meta-analysis concluded that without a health challenge, growth effects are small, whereas under challenge butyric acid improved weight gain and FCR to levels matching antibiotics. [3]
- In a 2,100-bird multi-form comparison, tributyrin (0.5 g/kg) was the only butyrate form that significantly lowered F/G over the full period and raised intestinal butyrate concentrations; coated and free sodium butyrate improved livability. Each form showed distinct strengths depending on the endpoint measured. [4]
- Published tributyrin dose–response work in broilers points to roughly 1,000–2,000 mg/kg of a ~72% product, with 1,500 mg/kg optimal; [5] industry practice for 60% tributyrin powders is 300–500 g/t depending on phase (company guidance). [11]
- Butyrate economics are not only about FCR: a commercial AA-broiler trial used 1.4 kg/t of a 60% tributyrin powder to remove 5 kg/t of added fat (~40 kcal/kg ME) while improving liveweight and margin per bird — company data, not peer-reviewed. [11]
1. Why butyrate belongs in the broiler conversation
Butyrate (butyric acid, C4:0) fuels enterocytes, supports villus growth and tight-junction integrity, modulates inflammation, and induces endogenous host defense peptides — a set of effects documented in detail in prior reviews. [1] Because free butyric acid is volatile, odorous and absorbed in the upper gut, commercial products deliver it as salts or esters: sodium butyrate (SB), coated/fat-matrix protected sodium butyrate, tributyrin (TB) and monobutyrin (MB). Tributyrin passes the stomach intact and is hydrolyzed stepwise by pancreatic lipases along the small intestine, releasing butyrate where epithelial turnover is highest — 1 mol of tributyrin yields 3 mol of butyric acid. [4],[5]
2. What the pooled evidence shows
Single trials vary; pooled analyses give the cleaner picture. A 2025 meta-analysis of protected sodium butyrate in broilers (17 experiments, 64 observations, 12,204 birds) reported:
| Response | Effect of protected sodium butyrate |
|---|---|
| Final body weight | +40 g (P < 0.05) |
| Average daily gain | +1.10 g/day (P < 0.05) |
| Feed conversion ratio | −0.015 units (P < 0.05) |
| Feed intake | Not affected |
| EPEF (European Production & Efficiency Factor) | Higher than control |
| Villus height / villus:crypt ratio | +9% / +5% |
Kihal, Puyalto & Mallo, Poultry Science 2025;104(11):105683, open access. [2]
A second meta-analysis of butyric acid in broilers reached an important nuance: the response depends on the microbiological challenge status of the flock. In flocks raised without health challenge, butyric acid — and antibiotics — did not influence growth performance; under challenge, butyric acid increased weight gain and significantly improved feed conversion, matching antibiotic results. [3] This frames realistic expectations: butyrate is a gut-health tool whose value concentrates where enteric pressure exists.
3. Form-by-form trial evidence in broilers
3.1 Tributyrin
- Dose–response (Peng et al., 2014): 1,800 male Avian broilers, 42 days, tributyrin at 0.10–0.40% of diet. Growth improved in a dose-dependent pattern with 0.20% optimal; crude fat and crude fiber apparent digestibility rose (P<0.05); duodenal and jejunal villus height increased (P<0.05); cecal Lactobacillus counts increased and E. coli counts decreased (P<0.05). [6]
- Dose–response (Lu et al., 2024): broilers fed 1,000 / 1,500 / 2,000 mg/kg of a 72% tributyrin product for 42 days. All levels increased 42-day body weight and ADG (P<0.05); 1,500 and 2,000 mg/kg lowered F/G (P<0.05); apparent digestibility of dry matter, crude protein, crude fiber and energy increased; serum total protein and HDL rose while total cholesterol and triglycerides fell. The authors concluded 1,500 mg/kg was optimal. [5]
- Multi-form comparison (Yan et al., 2023): see Section 4 — the most directly decision-relevant trial published to date. [4]
3.2 Coated (protected) sodium butyrate
In a 42-day Ross 308 trial, 500 mg/kg coated sodium butyrate significantly reduced F/G at 22–42 d and over the full period, increased ADG and the European efficiency index, reduced drip loss and shear force of breast meat, and increased cecal α-diversity indices (Chao1, Shannon, Pielou) and the relative abundance of Parabacteroides. [7]
3.3 Sodium butyrate versus in-feed antibiotics
In a 42-day AA-broiler trial, 500 mg/kg sodium butyrate outperformed both amoxicillin and enrofloxacin groups on 42-day weight gain (+11.24% vs control) and F/G (−10.75% vs control; −11.57% vs amoxicillin; −4.50% vs enrofloxacin), with numerically higher bursa and spleen indices and a better liver/kidney enzyme profile — reported by the study authors as a possible "feed antibiotic replacement" role. Note the small scale of this study (6 birds per replicate). [8] This is a research finding, not a recommendation to replace any prescribed veterinary treatment.
3.4 Pathogen-control endpoints
- Dietary 0.1% butyrate induced host defense peptide gene expression in the intestinal tract and produced a nearly 10-fold reduction in cecal Salmonella Enteritidis titer after experimental infection. [9]
- In two necrotic-enteritis challenge trials, micro-encapsulated (target-released) butyric acid reduced the proportion of birds with necrotic lesions in one trial, and combinations of butyric acid with medium-chain fatty acids and essential oils reduced lesions in the other — a reminder that dose, coating and combination all matter under heavy challenge. [10]
4. The multi-form comparison: SB vs TB vs MB vs virginiamycin
Yan et al. (2023) ran the comparison feed formulators actually ask for: 2,100 Ross 308 day-old chicks, 5 groups × 12 replicates, 39 days — negative control (NC), antibiotic control (10 mg/kg virginiamycin), sodium butyrate (0.5 g/kg), tributyrin (0.5 g/kg) and monobutyrin (1.0 g/kg). [4]
| Finding | Result |
|---|---|
| Day 1–10 | No significant differences in F/G, ADFI or livability among treatments; TB group BW and ADG were significantly lower than NC and SB (P<0.05) — a transient early effect. |
| Day 25–39 and overall F/G | Virginiamycin and tributyrin significantly lower than NC (P<0.05); SB and MB not significant on this endpoint. |
| Livability, overall | SB +1.86%, TB +1.86%, MB +4.49% vs NC. |
| Intestinal butyrate (metabolism trial, equal butyrate-ion 1.0 g/kg) | TB significantly increased duodenal and jejunal butyrate (P<0.05); intestinal butyrate declined from duodenum to ileum, consistent with stepwise ester hydrolysis. |
| Authors' conclusion | Butyrate improved gain and lowered F/G and benefited gut development; on the F/G and intestinal-butyrate endpoints, glycerol-esterified forms performed better than free SB under these trial conditions. |
Adapted from Yan et al., Chinese Journal of Animal Nutrition 2023;35(11):7002–7013. doi:10.12418/CJAN2023.638. [4]
We deliberately report the day 1–10 setback for TB: honest reading of the data shows tributyrin's benefits emerge from mid-period onward, which is one reason programs pair tributyrin with phase-appropriate dosing rather than expecting a starter-phase growth response.
5. Doses: what the trials used, and practical programs
Comparing doses across studies requires converting to a common basis. Sodium butyrate powder (≥98.5%) contains ~79% butyrate ion; a 30% coated SB product contains ~24%; tributyrin contains ~86% butyrate ion by weight (company specifications). [11]
| Form | Published trial dose | Practical inclusion (company guidance) |
|---|---|---|
| Sodium butyrate (powder/granule) | 500 mg/kg in comparison trials [8] | 0.5–2 kg/t |
| Coated sodium butyrate (30%) | 500 mg/kg (42 d, Ross 308) [7] | 0.5–1 kg/t |
| Tributyrin (purified / powder) | 1,000–2,000 mg/kg of a 72% product, 1,500 optimal [5]; 0.2% of pure TB optimal [6]; 0.5 g/kg vs SB [4] | 60% powder: 500 g/t starter → 300 g/t grower–finisher; 0.3–1 kg/t range |
| Monobutyrin | 1.0 g/kg in multi-form trial [4] | Per product specification |
Practical inclusion ranges: SKF Bio internal technical review (2024), company data, not peer-reviewed. [11]These are formulation practices reported from commercial experience, not regulatory clearances — see the regulatory note in Section 6 before applying them in any market.
Company data · not peer-reviewed
5.1 A worked commercial program
A 39-day commercial AA-broiler trial (August–October 2022, China) tested whether a 60% tributyrin powder could replace energy, not just replace an additive. The test group received basal diet + 1.4 kg/t tributyrin powder while removing 5 kg/t of added fat (~40 kcal/kg ME reduction); four control houses kept the fat and their usual additives. Liveweight price for margin: ¥8.6/kg.
| Indicator | Controls (n=4) | Tributyrin group |
|---|---|---|
| Final body weight (kg) | 2.525–2.673 (mean 2.606) | 2.719 (+113 g, +4.3%) |
| Feed intake (kg) | 3.747–3.893 | 3.934 |
| Feed conversion (F/G) | 1.430–1.497 (mean 1.466) | 1.447 |
| Feed price (¥/kg) | 4.546–4.552 | 4.541 |
| Cost per kg live gain (¥/kg) | 6.508–6.804 (mean 6.671) | 6.569 |
| Margin per bird (¥/bird) | 4.657–5.591 (mean 5.033) | 5.521 (+0.49, ~+10%) |
SKF Bio internal trial record, 2022 — company data, not peer-reviewed; single farm, single production cycle, results will vary with stock, management and market prices. [11] Read honestly: the tributyrin group's F/G was mid-range among controls, not the best; the economic result came from liveweight gain at a lower feed energy specification and lower cost per kg of gain.
6. Practical notes on formulation, stability and QC
- Pelleting: tributyrin is thermostable under normal pelleting conditions and carries an ester (not rancid) odor; free sodium butyrate is hygroscopic and odorous, which is why coated and esterified forms dominate commercial feed. Company statement, not an independent measurement. [11]
- Specification discipline: tributyrin products of nominally similar concentration vary in what the carrier actually holds. Gas chromatography quantifies the tributyrin fraction and reveals impurities such as free butyric acid, mono- and di-butyryl esters and water — these should appear on the certificate of analysis. Our own liquid grade is specified at ≥98% tributyrin (typical measured value 98.7%, total esters 99.13%). [11] This is a self-declared specification, not a comparative claim about other suppliers' products.
- Butyrate-ion equivalence: when switching between forms (SB ↔ coated SB ↔ TB), convert doses on a butyrate-ion basis rather than copying mass-for-mass — a 500 g/t switch between a 30% coated product and a 60% tributyrin powder is not an equivalent dose. [11]
7. Limitations to keep in mind
- Responses concentrate under enteric challenge; in clean, low-pressure flocks, expect modest or non-significant F/G effects. [3]
- Feed intake is generally unchanged — gains in performance come through digestibility and gut morphology, not appetite. [2],[5]
- Early-life responses can be flat or even transiently negative for tributyrin (day 1–10 in the multi-form trial). [4]
- Some endpoint studies (e.g., 260 mg/kg butyrate comparisons in 2025) report little effect on performance or barrier function, so dose and product quality remain decisive. [12]
- The commercial economics in Section 5.1 are company data, not peer-reviewed; replicate on your own stock before locking formulations.
Frequently asked questions
What inclusion rate of tributyrin should I use in broilers?
Published dose–response work with a ~72% tributyrin product found 1,000–2,000 mg/kg effective with 1,500 mg/kg optimal; [5] earlier work with pure tributyrin found 0.2% of diet optimal. [6] For commercial 60% tributyrin powders, industry practice is roughly 500 g/t in the starter phase stepping down to 300 g/t in grower–finisher. [11] When comparing products, normalize on butyrate-ion content.
Can tributyrin replace part of the added fat or energy in the formula?
In a commercial AA-broiler trial, 1.4 kg/t of a 60% tributyrin powder replaced 5 kg/t of added fat (~40 kcal/kg ME) while improving liveweight by ~4% and margin per bird by ~10%, at a feed price slightly below the controls. [11] These are company data, not peer-reviewed — treat them as a hypothesis to validate in your own conditions, not a formulation guarantee.
Tributyrin or coated sodium butyrate — which should I choose?
Both are effective, with different strengths. In the only published multi-form trial with a matched butyrate basis, tributyrin was the only form to significantly lower F/G over the full period and significantly raise duodenal/jejunal butyrate, while sodium butyrate and monobutyrin led on livability. [4] Separately, 500 mg/kg coated sodium butyrate improved F/G, EPEF and meat quality in its own trial. [7] The decision usually comes down to target intestinal segment, pelleting constraints, odor requirements and cost per unit of delivered butyrate-ion.
Will butyrate still pay off if my flocks are healthy?
Meta-analytic evidence indicates the largest gains occur under microbiological challenge; in unchallenged flocks, butyric acid and antibiotics both showed little effect on growth. [3] The practical reading: butyrate is cheapest insurance where enteric pressure (coccidiosis, necrotic enteritis risk, wet litter) exists, and a refinement tool rather than a growth promoter in very clean systems.
Does it help against Salmonella and necrotic enteritis?
Dietary butyrate (0.1%) induced host defense peptide expression and reduced cecal Salmonella Enteritidis titer nearly 10-fold after experimental infection. [9] For necrotic enteritis, target-released butyric acid reduced lesion prevalence in one of two challenge trials, and butyric-acid-containing combinations were more consistent than butyric acid alone. [10] Both are controlled experimental infection models: they describe research findings, not a claim that any product prevents or treats salmonellosis or necrotic enteritis, and not a substitute for a veterinary health and biosecurity programme.
References
- Bedford A, Gong J. Implications of butyrate and its derivatives for gut health and animal production. Animal Nutrition. 2018;4(2):151–159. doi:10.1016/j.aninu.2017.08.010 (open access).
- Kihal A, Puyalto M, Mallo JJ. Effect of feeding protected sodium butyrate on production performance and intestinal morphology of broilers: A meta-analysis. Poultry Science. 2025;104(11):105683. doi:10.1016/j.psj.2025.105683 (open access).
- Giacomini PV, Braga FSC, Araujo RGAC, Cruz-Polycarpo VC, Polycarpo GV. Meta-analysis of butyric acid: a performance-enhancing additive to replace antibiotics for broiler chickens. Revista Brasileira de Ciência Avícola. 2022;24(3). doi:10.1590/1806-9061-2021-1463 (open access).
- Yan L, An S, Gao J, Lü Z, Wang T, Wang Z, Zhou G, Li Y, Guo Y, Jia Y. Effects of dietary supplementation of different butyrate dosage forms on growth performance, intestinal health, and footpad and gait scores of broilers. Chinese Journal of Animal Nutrition. 2023;35(11):7002–7013. doi:10.12418/CJAN2023.638.
- Lu W, Yang H, Chen Z, Cao Y, Wang M, Yin S, Wang Y. Effects of dietary tributyrin on growth performance, nutrient digestibility and serum biochemical indices of broilers. China Feed. 2024;(4):45–48. doi:10.15906/j.cnki.cn11-2975/s.20240412.
- Peng L, Sun J, Shi Y, Zhu G, Li W, Yu D. Effects of tributyrin on growth performance, nutrient apparent digestibility, slaughter performance, intestinal morphology and microflora of broilers. Chinese Journal of Animal Nutrition. 2014;26(2):466–473. doi:10.3969/j.issn.1006-267X.2014.02.023.
- Ma S, Song Y, Lin X, Zeng S, Peng H, Yang Y, Zhao X, Li H. Effects of coated sodium butyrate on growth performance, meat quality, serum biochemical indices and cecal microbial structure of broilers. Chinese Journal of Animal Nutrition. 2025;37(2):950–960. doi:10.12418/CJAN2025.083.
- Li X, Qian L, Ou D. Effects of sodium butyrate on growth performance, immune performance and serum biochemical indices of broilers. China Feed. 2022;(17):50–54. doi:10.15906/j.cnki.cn11-2975/s.20221709.
- Sunkara LT, Achanta M, Schreiber NB, et al. Butyrate enhances disease resistance of chickens by inducing antimicrobial host defense peptide gene expression. PLoS ONE. 2011;6(11):e27225. doi:10.1371/journal.pone.0027225 (open access).
- Timbermont L, Lanckriet A, Dewulf J, et al. Control of Clostridium perfringens-induced necrotic enteritis in broilers by target-released butyric acid, fatty acids and essential oils. Avian Pathology. 2010;39(2):117–121. doi:10.1080/03079451003610586.
- SKF (Beijing) Biotechnology Co., Ltd. Butyrate salts and esters in broiler production: internal technical review, product specifications and commercial farm trial record (2022–2024). Company data, not peer-reviewed.
- Pearce SC, Kerr BJ, Monson MS, Ramirez SM. Dietary butyrate effects on broiler growth, intestinal morphology and integrity, cecal volatile fatty acid concentrations and colonic bacteria in broilers. Poultry Science. 2025;104(12):105898.
- EU regulatory status of glyceryl tributyrate: Commission Implementing Regulation (EU) 2017/54 (additive 2b09211, glyceryl tributyrate, CAS 60-01-5, FLAVIS 09.211; sensory additives, functional group 2b flavouring compounds; authorisation expires 6 February 2027). Verified against the EU/GB Register of Feed Additives (GB register entry feedadd-809).
About the author and conflict of interest: Shouhui Chen is with SKF (Beijing) Biotechnology Co., Ltd., which manufactures and sells butyric acid and butyrate ester products. This article is published with that commercial interest disclosed.
Disclaimer: This article summarises published research and internal company data for technical information only. It is not peer-reviewed as a publication, is not veterinary or medical advice, and is not a substitute for professional veterinary or nutritionist guidance. Findings attributed to studies are the conclusions of those studies, under their own experimental conditions; they are not product efficacy claims and not a guarantee of comparable results. Figures from our own work are identified as "company data, not peer-reviewed" and come from single-site or single-cycle observations. Nothing here is a claim that any substance prevents, treats, cures or reduces the risk of disease in animals.
Regulatory notice: The regulatory status of tributyrin, sodium butyrate and coated butyrate products, and the claims permitted for them, differ by country and by intended function — in the EU, the existing authorisation for glyceryl tributyrate is a sensory/flavouring authorisation (additive 2b09211) with a recommended maximum of 5 mg/kg complete feed, which does not cover performance or gut-health claims. Do not reproduce any statement from this article on product labels, in advertising, or in sales material without confirming the current authorisation status and permitted claims with the competent authority in the target market.
Related products
Tributyrin powders, coated sodium butyrate and technical documents referenced in this article.