Gut Health & Nutrition Library · Pillar Article
How Butyrate and Butyrate Esters Work in the Gut: Mechanisms, Evidence Strength and Boundaries
What butyrate actually does at the intestinal level, why the delivery form changes where it works, which of the five proposed mechanisms are well supported and which are not, and where the trial evidence stops. Written for nutritionists and technical buyers in pigs and poultry.
Author: Shouhui Chen — SKF (Beijing) Biotechnology Co., Ltd. · Last updated: 28 September 2026 · Reading time: ~13 min
Key takeaways
- Butyrate is not an exotic input — it is already in the gut, but very unevenly: roughly 0.1–0.2 mmol/L in the broiler small intestine versus 7–17 mmol/L in the caeca, and about 2.2 / 2.8 / 10.4 mmol/L in the jejunum / ileum / caecum of weanling pigs. [2] Supplementation is largely about getting butyrate to the segments where endogenous supply is thin.
- Form decides release site. Sodium salts dissociate early and are absorbed fast; butyrate glycerides pass the stomach intact and are cleaved by pancreatic lipase along the small intestine; coating shifts release further distally. None is universally "better" — they answer different questions. [1]
- Of the five commonly cited mechanisms, enterocyte energy supply is well established, gene-expression and host-defence-peptide induction has strong experimental support mostly in chickens, [2],[9] and barrier, cytokine and pathogen-load effects are real but context-dependent, with much of the barrier evidence coming from disease models rather than field trials. [1]
- The most consistent performance signal across species is early and challenge-linked: the first two weeks after weaning in pigs, [11],[12] and infected or challenged flocks in broilers. [7],[10] In unchallenged, well-managed animals the effect is smaller.
- Negative results matter and are kept here: a tributyrin glyceride programme in calves changed glucose and insulin dynamics without improving growth; [1] a butyrate meta-analysis found no significant effect on intestinal morphology; [11] and in a 2,100-bird head-to-head trial tributyrin lowered body weight gain relative to controls in the 1–10 day window. [8]
- Regulatory reality check: butyrate products are not authorised for the same claims in every market. In the EU, glyceryl tributyrate holds a flavouring-only authorisation (2b09211, recommended maximum 5 mg/kg complete feed); [21] in the US, tributyrin is affirmed GRAS as a human food flavouring under 21 CFR 184.1903, which is not itself an animal-feed authorisation. [23] See Section 7.
1. Start from what is already there
Before discussing what to add to feed, it helps to know what the animal already produces. Butyrate is one of the three major short-chain fatty acids made by microbial fermentation, and it is the preferred energy substrate of colonocytes. How much is present depends heavily on species, age, diet and — above all — on where in the gut you measure. [2]
| Species / segment | Reported butyrate concentration | Practical reading |
|---|---|---|
| Broiler — duodenum, jejunum, ileum | 0.1–0.2 mmol/L of digesta [2] | Very thin. This is the segment where absorption happens and where supplemental butyrate has the most room to matter. |
| Broiler — caeca | 7–17 mmol/L, varying with bird age [2] | Already rich. Adding more here is unlikely to change much. |
| Weanling pig — jejunum / ileum / caecum | 2.2 / 2.8 / 10.4 mmol/L of digesta [2] | Same gradient as the bird: proximal segments are the gap. |
| Cattle — rumen fluid | 10–15 mmol/L [2] | Ruminants are a different problem entirely. |
Short-chain fatty acids generated in the large intestine are estimated to supply around 24% of the energy used for heat production in pigs. [2] Two consequences follow. First, the target for supplementation is not "more butyrate everywhere" but "butyrate in the proximal intestine during the window when intake and barrier function are under pressure". Second, because fermentation capacity is immature in the young animal — at weaning and in the first days post-hatch — the endogenous supply is at its weakest exactly when the gut is under the most stress.
2. Why the form matters: chemistry decides the release site
Free butyric acid works, but it is volatile, has an offensive odour, and is largely absorbed or ionised in the upper gut. Everything sold as a "butyrate product" is an answer to that handling problem, and each answer shifts where the butyrate ends up. [1]
| Form | What happens in the gut | Where butyrate is released | Trade-offs |
|---|---|---|---|
| Sodium butyrate (uncoated) | Water-soluble salt, dissociates readily; ~80% butyrate by mass | Stomach and proximal small intestine | Simple and cheap; strong odour, hygroscopic, absorbed early |
| Coated / protected sodium butyrate | Fat, ethyl-cellulose or MCFA-salt coating delays dissolution | Mid to distal small intestine, depending on coating | Better reach and handling; coating dilutes content (30–70% typical) |
| Tributyrin (glyceryl tributyrate) | Triglyceride; passes the stomach intact, hydrolysed by pancreatic lipase | Progressive release along the small intestine | ~87% butyrate by mass on complete hydrolysis; low odour; needs lipase activity, may not liberate completely |
| Monobutyrin / butyrate glyceride blends | Partial glycerides, sometimes blended with MCFA glycerides | Small intestine; blend composition sets the profile | Products differ a great deal in what the label percentage actually refers to |
That last row is where most buying mistakes are made. "60% tributyrin" does not tell you whether the remainder is carrier, free butyric acid, mono- and di-esters or water. Ask for a certificate of analysis that quantifies the tributyrin fraction and reports free acid, partial esters and moisture — and convert on butyrate ion, not on bag weight (Section 5).
3. Five mechanisms, ranked by how well they are actually supported
3.1 Energy substrate for intestinal cells — well established
Butyrate is the primary energy source for colonocytes and a major oxidative substrate for enterocytes. This is the least controversial of the five mechanisms and underpins most of the growth and digestibility findings discussed in our species articles. [1],[2]
3.2 Gene expression and host defence peptides — strong, species-skewed
Beyond fuel, butyrate acts as a cellular mediator: it influences gene expression, cell differentiation and tissue development. In chickens, dietary butyrate induced antimicrobial host defence peptide gene expression and was associated with a large reduction in Salmonella Enteritidis titre after experimental infection. [9] A 2018 review of this area places butyrate among the dietary tools that can modulate endogenous host defence peptide synthesis. [2] The honest caveat: the clearest HDP data are chicken and in vitro; comparable in vivo evidence in pigs is thinner.
3.3 Barrier function and tight junctions — supported, largely in models
Butyrate glyceride supplementation has been reported to reduce pro-inflammatory cytokine expression and improve tight-junction formation in the colon, and — in a porcine colitis model — 1,000 mg/kg tributyrate glyceride alleviated intestinal injury, with inhibition of apoptosis, promotion of tight-junction formation and activation of EGFR signalling proposed as mechanisms. [1] Read this as model evidence. It tells us the mechanism is plausible and measurable; it does not license a field claim about intestinal barrier or disease.
3.4 Immune modulation — real but conditional
In chickens, butyrate has minimal effect on basal expression of IL-1β, IL-6, interferon-γ or nitric oxide, but suppresses the induction of these mediators by lipopolysaccharide both in vitro and in vivo. [2],[9] In weanling pigs, dietary sodium butyrate reduced serum IL-6 and TNF-α. [2] This pattern — little effect on a calm animal, dampening of an excessive response under challenge — is the mechanistic twin of the "effects show up under challenge" finding seen in the performance literature. [7] Under an experimental ETEC co-infection, butyrate and valerate glycerides affected diarrhoea severity and immune response in weaned piglets. [17]
3.5 Microbiota and pathogen load — context-dependent
The general organic-acid mechanism is that the non-dissociated molecule can diffuse through the lipophilic bacterial membrane and disrupt enzymatic reactions and transport systems; [5] butyrate adds the epithelial and immune effects described above on top of that. Target-released butyric acid, alone and combined with medium-chain fatty acids and essential oils, has been studied against Clostridium perfringens-induced necrotic enteritis in broilers, with lesion outcomes differing between trials and combinations performing more consistently than butyric acid alone. [10] In finishing pigs, feeding sodium butyrate in the late finishing period affected Salmonella carriage and seroprevalence in one of two farm trials, and did not consistently reduce intestinal carriage; [15] a related organic-acid study in grower pigs reported clearer effects. [16] Protected sodium butyrate has also been studied against Salmonella infection dynamics in fattening pigs. [18] Treat all of this as "directionally supportive, farm-dependent".
4. An honest scorecard: what the evidence supports, and where
The table below maps the endpoints that come up in technical conversations against what the literature actually shows. It deliberately includes the weak and null rows.
| Endpoint | Species | Direction and strength | Main sources |
|---|---|---|---|
| Growth in the first two weeks post-weaning | Pigs | Positive and the most repeatable window: body weight gain (P=0.004), feed intake (P=0.010) and FCR (P=0.002) improved in the first fortnight | Sodium butyrate meta-analysis [11] |
| Weaner ADG, F/G and diarrhoea rate | Pigs (glycerides) | Positive: ADG SMD 1.58, F/G SMD −0.85, diarrhoea SMD −2.78; feed intake not significant. Large effects, high heterogeneity, several small trials | Tributyrin meta-analysis, 12 studies / 838 pigs [12] |
| Intestinal morphology (villus height, crypt depth) | Pigs and broilers | Mixed. One meta-analysis found no significant effect on morphology parameters; [11] a broiler meta-analysis reported villus height about +9% [6] | [6],[11] |
| Broiler FCR and body weight | Broilers | Small but consistent: in a meta-analysis of protected sodium butyrate (17 experiments, 12,204 birds) final body weight +40 g, ADG +1.10 g/day, FCR improved by 0.015 | [6] |
| Performance under health challenge | Both | The most consistent context. Under challenge, butyric acid improved weight gain and FCR to levels comparable with the antibiotic comparators used in those trials | [7],[10],[17] |
| Performance without challenge | Both | Small. A meta-analysis concluded that without a health challenge growth effects are limited | [7] |
| Head-to-head comparison of forms | Broilers | In a 2,100-bird trial, tributyrin at 0.5 g/kg was the only form that significantly lowered F/G over the full period and raised intestinal butyrate; the authors concluded esterified forms outperformed the salt, with tributyrin best. But tributyrin lowered gain versus control in the 1–10 day window | [8] |
| Body composition | Broilers | Relative breast muscle weight rose dose-dependently between 500 and 3,000 mg/kg of a butyrate glyceride product (P=0.0074) while ADG was unaffected — manufacturer-reported, unpublished. Reduced relative abdominal fat was seen across several studies with monobutyrin, tributyrin and their mixture | [1] (unpublished data flagged by the authors) |
| Grower–finisher pigs | Pigs | Sparse: a small number of trials and one thesis with 10 pigs per group | see the swine article |
| Sow and gilt reproduction | Pigs | Largely unaffected in the gilt trial; positive findings were in piglet growth and colostrum composition | see the swine article |
| Pathogen shedding / carriage | Both | Farm-dependent: one of two finishing-pig trials showed an effect on Salmonella, the other did not | [15],[16],[18] |
| Pre-weaning calves | Calves | Null for growth: tributyrate glycerides at 3,000 mg/kg modulated glucose and insulin dynamics without improving growth performance | [1] |
5. Dose: convert on butyrate ion, not on bag weight
Products are sold by mass, but animals respond to butyrate. Two conversions do most of the work:
- Sodium butyrate (C₄H₇O₂Na, MW 110.09) carries about 80% butyrate by mass.
- Tributyrin (C₁₅H₂₆O₆, MW 302.36) carries three butyrate residues — about 87% by mass if fully hydrolysed.
So 1 kg/t of a 60% tributyrin powder delivers roughly 0.52 kg of butyrate-equivalent, while 1 kg/t of a 30% coated sodium butyrate delivers about 0.24 kg. Swapping one for the other at equal inclusion rate is close to a two-fold change in delivered butyrate before you account for where each releases. Do the arithmetic before comparing prices.
| Species / phase | Tributyrin | Coated sodium butyrate | Butyrate ion delivered | Evidence strength |
|---|---|---|---|---|
| Broiler, full cycle | 1,000–2,000 mg/kg of a ~72% product, 1,500 mg/kg optimal [19]; 0.5 g/kg in head-to-head work [8] | 500 mg/kg of a 30% coated product, 42-day trial [20] | ~0.63–1.25 g/kg from tributyrin; ~0.12 g/kg from the coated salt | Moderate. One dose–response trial, one 2,100-bird head-to-head [8],[19]; company practice 300–500 g/t by phase [22] |
| Weaned piglet / nursery | 1,000–2,500 mg/kg against a bacitracin-zinc comparator, 2,000–2,500 mg/kg adding performance on top [13]; 0.2% in independent nursery trials [14] | 1 kg/t of an MCFA-protected product in weaners | ~0.87–2.18 g/kg from tributyrin at 1,000–2,500 mg/kg of pure ester; ~0.24 g/kg from 1 kg/t of a 30% coated salt | Strongest window. Two independent meta-analyses, effects concentrated in the first fortnight [11],[12] |
| Grower–finisher pig | Limited published dose–response | 2 kg/t of a ≥30% coated product in one trial | ~0.48 g/kg from 2 kg/t of a 30% coated salt; no tributyrin dose–response published | Weak. A small number of trials, one thesis with 10 pigs per group |
| Sow / gilt | No dose–response located | 0.05–0.1% sodium butyrate in two theses | ~0.4–0.8 g/kg at 0.05–0.1% sodium butyrate | Mixed to null for reproduction. Reproductive parameters largely unaffected; signals were in piglet growth and colostrum composition |
Butyrate-ion figures are calculated from the labelled assay at the top of each range (sodium butyrate ≈80% butyrate by mass, tributyrin ≈87%) and assume complete hydrolysis; real delivery depends on hydrolysis efficiency, coating integrity and transit time. The much lower ion figure for coated salts is not a disadvantage in itself — those products are designed to release later and are often used at 1–3 kg/t precisely because of that.
Practical inclusion ranges marked as company guidance are SKF Bio internal technical recommendations — company data, not peer-reviewed. [22]
6. Where the boundaries are
Butyrate is not a dose-linear input. Responses peak at an optimum rather than rising with inclusion, they depend on challenge pressure and animal state, and butyrate can stimulate normal cells while inhibiting transformed ones — so more is not automatically better.
- Mechanisms are better documented than outcomes. Much of the barrier and tight-junction evidence comes from disease models and in vitro systems rather than commercial trials. [1]
- Species translation is uneven. Host defence peptide induction is best documented in chickens; [9] assuming the same magnitude in pigs is not supported by the pig literature we could find.
- A major 2018 review of non-antibiotic feed additives for pigs does not give butyrate a dedicated efficacy section, treating it within the general acidifier and SCFA discussion. [3] That is a fair signal about where butyrate sits in the evidence hierarchy for pigs.
- "Gut health" itself has no agreed definition. A widely cited review notes the term lacks a clear definition or aetiology, and in broad terms covers digestion and absorption, host metabolism and energy generation, a stable microbiota, barrier function and mucosal immune mechanisms, and the interactions between them. [4] Any claim that a product "improves gut health" inherits that ambiguity.
- Heterogeneity is high. Meta-analyses in both species report large pooled effects alongside wide variation between trials, so a single trial — including a favourable one — should not anchor a formulation decision. [11],[12]
- Null results are part of the picture: no morphology effect in one meta-analysis, [11] no growth response in calves, [1] and no effect in one of two Salmonella farm trials. [15]
7. Regulatory status — read this before you repeat any claim
- European Union: glyceryl tributyrate (CAS 60-01-5, FLAVIS 09.211) is an authorised feed additive under identification number 2b09211 — category "sensory additives", functional group 2b "flavouring compounds", authorised by Commission Implementing Regulation (EU) 2017/54, with a recommended maximum of 5 mg/kg complete feed (12% moisture). [21] Butyric acid and a range of esters were (re)authorised as flavouring compounds for all animal species by Commission Implementing Regulation (EU) 2023/1417. [21] These are flavouring authorisations: they do not cover zootechnical claims such as growth promotion or gut-health support, and they sit orders of magnitude below the inclusion levels discussed here.
- United States: tributyrin (glyceryl tributyrate, CAS 60-01-5) is affirmed GRAS as a direct human food ingredient under 21 CFR 184.1903, where its stated function is "flavouring agent and adjuvant", used at levels not to exceed current good manufacturing practice; it also carries FEMA No. 2223 and JECFA flavouring No. 922. [23] For animal feed use, ingredient status runs through the AAFCO Official Publication and FDA CVM's enforcement policy for AAFCO-defined ingredients (GFI #293, finalised October 2024) — the human-food GRAS affirmation is not by itself a feed authorisation.
- Other markets: most require registration or notification by species and by claimed function. Where a product is placed as a feed material rather than an additive, the claims that may be made are typically narrower. Treat "legal to import" and "legal to claim" as two separate questions.
- China (country of manufacture, for reference): butyric acid and sodium butyrate are listed in the Feed Additive Catalogue with a scope of "all farmed animals", whereas tributyrin was approved as a new feed additive for broiler chickens (Ministry of Agriculture and Rural Affairs Announcement No. 614, November 2022), with the usual five-year monitoring period running to late 2027. [24] Chinese approval scope does not determine what may be claimed in your market.
Frequently asked questions
Is tributyrin simply a slow-release form of butyrate?
Not exactly. It is a triglyceride that resists gastric conditions and is hydrolysed by pancreatic lipase, releasing butyrate progressively along the small intestine rather than at one point. [1] That also means it depends on lipase activity, and hydrolysis may not be complete — which is one reason results vary between young and older animals.
Does a higher inclusion rate always work better?
No. Published dose–response work tends to find an optimum rather than a monotonic response; broiler work with a ~72% tributyrin product identified 1,500 mg/kg as optimal within a 1,000–2,000 mg/kg range. [19] Mechanistically, butyrate's effects are cell-state dependent — it supports normal enterocytes while inhibiting proliferation in cancerous cells [2] — so "more" is not automatically "better".
Why do results differ so much between farms and trials?
Because the effect is largely conditional. Both meta-analyses point the same way: responses are largest in the early post-weaning window in pigs [11] and in birds or pigs facing a health challenge, [7],[10] and much smaller where animals are already healthy and well managed. Baseline diet, hygiene, stocking density and the comparator used all move the result.
Which reaches the hindgut — a coated salt or an ester?
They arrive by different routes and at different points. Coated sodium butyrate is designed to carry butyrate further distally before dissolving; tributyrin is cleaved by lipase along the small intestine. [1] If your target is the distal small intestine or beyond, a coated or protected product is the usual answer; if it is the proximal small intestine where endogenous butyrate is thinnest, an ester or an uncoated salt may be more relevant.
Can butyrate replace antibiotics?
That is how several studies frame the question, and some trials do compare butyrate against antibiotic growth promoters — for example tributyrin against bacitracin zinc in weaned piglets. [13] But "performed comparably in a given trial" is a research finding, not a regulatory authorisation, and it is not a claim we make for any product. Antimicrobial stewardship decisions belong with your veterinarian.
How should I compare two commercial products?
On delivered butyrate ion per tonne of feed at the intended release site, plus the certificate of analysis. Ask for the tributyrin or sodium butyrate assay, free butyric acid, mono- and di-ester content and moisture; then convert to butyrate-equivalent and compare cost per kilogram delivered, not cost per kilogram of product.
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).
- Robinson K, Ma X, Liu Y, Qiao S, Hou Y, Zhang G. Dietary modulation of endogenous host defense peptide synthesis as an alternative approach to in-feed antibiotics. Animal Nutrition. 2018;4(2):160–169. doi:10.1016/j.aninu.2018.01.003.
- Liu Y, Espinosa CD, Abelilla JJ, Casas GA, Lagos LV, Lee SA, Kwon WB, Mathai JK, Navarro DMDL, Jaworski NW, Stein HH. Non-antibiotic feed additives in diets for pigs: A review. Animal Nutrition. 2018;4(2):113–125. doi:10.1016/j.aninu.2018.01.007.
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- Mehdi Y, Létourneau-Montminy M-P, Gaucher M-L, Chorfi Y, Suresh G, Rouissi T, Brar SK, Côté C, Ramirez AA, Godbout S. Use of antibiotics in broiler production: Global impacts and alternatives. Animal Nutrition. 2018;4(2):170–178. doi:10.1016/j.aninu.2018.03.002.
- 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.
- 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.
- Chalvon-Demersay T, et al. Meta-analysis of effects of sodium butyrate supplementation on the performance and intestinal morphology of post-weaning piglets. Proceedings of the 10th Symposium on Gut Health in Production of Food Animals, St. Louis, Missouri, 2022. (Conference meta-analysis, 9 studies.)
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- Walia K, Argüello H, Lynch H, Leonard FC, Grant J, Yearsley D, Kelly S, Duffy G, Gardiner GE, Lawlor PG. Effect of feeding sodium butyrate in the late finishing period on Salmonella carriage, seroprevalence, and growth of finishing pigs. Preventive Veterinary Medicine. 2016;131:79–86.
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- Kovanda L, Park J, Li X, et al. Dietary butyrate and valerate glycerides impact diarrhea severity and immune response of weaned piglets under ETEC F4–ETEC F18 coinfection conditions. Journal of Animal Science. 2023;101:skad401. doi:10.1093/jas/skad401.
- Casanova-Higes A, Andrés-Barranco S, Mainar-Jaime RC. Effect of the addition of protected sodium butyrate to the feed on Salmonella spp. infection dynamics in fattening pigs. Animal Feed Science and Technology. 2017;231:12–18.
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- 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.
- EU regulatory status: Commission Implementing Regulation (EU) 2023/1417 of 5 July 2023 concerning the authorisation of butyric acid and other substances as feed additives for all animal species (functional group: flavouring compounds); Commission Implementing Regulation (EU) 2017/54 — additive 2b09211, glyceryl tributyrate, CAS 60-01-5, FLAVIS 09.211, sensory additives / flavouring compounds, recommended maximum 5 mg/kg complete feed (12% moisture), authorisation expires 6 February 2027.
- SKF (Beijing) Biotechnology Co., Ltd. Internal technical review: butyrate salts and esters — specifications, release-site mapping and phase inclusion guidance (2022–2024). Company data, not peer-reviewed.
- US regulatory status: 21 CFR 184.1903 — Tributyrin (CAS Reg. No. 60-01-5), affirmed GRAS as a direct human food ingredient, function "flavouring agent and adjuvant", use not to exceed current good manufacturing practice; FEMA No. 2223; JECFA flavouring No. 922. FDA CVM, Guidance for Industry #293: FDA Enforcement Policy for AAFCO-Defined Animal Feed Ingredients (final, October 2024).
- China regulatory status: Feed Additive Catalogue (饲料添加剂品种目录) — butyric acid and sodium butyrate listed under preservatives, mould inhibitors and acidity regulators, scope "all farmed animals"; tributyrin approved as a new feed additive for broiler chickens, Ministry of Agriculture and Rural Affairs Announcement No. 614 (November 2022), five-year monitoring period to late 2027.
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 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. Some cited findings come from disease models, in vitro systems, conference abstracts or manufacturer-reported datasets, and are identified as such. Nothing here is a claim that any substance prevents, treats, cures or reduces the risk of disease in animals.
Regulatory notice: This article is written for an international audience. The regulatory status of butyric acid, sodium butyrate, tributyrin and coated butyrate products, and the claims permitted for them, differ by country, by target species and by intended function. In the EU the existing authorisation for glyceryl tributyrate is a sensory/flavouring authorisation that does not cover performance or gut-health claims; in the US, tributyrin's GRAS status is a human-food affirmation and not by itself an animal-feed authorisation. Do not reproduce any statement from this article on product labels, in advertising or in sales material without confirming the current authorisation status, approved species 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.