Early pilot and prior studies point to increased butyrate and reduced spirochete signals; Tharos advances controlled veterinary trials

(Press-News.org) Greenacres, FL and London, UK — July 31, 2025

Tharos Ltd today announced encouraging exploratory findings from a small, uncontrolled pilot evaluation of its enzyme‑rich malt extract (ERME), marketed as EquiNectar® for horses and CaniNectar® for dogs, and sold since 2018 as an animal feed supplement. Over four weeks, stool 16S rRNA gene sequencing showed a directional decline in low‑abundance sequence reads annotated to the genus Borrelia in a subset of animals. While stool‑based, genus‑level annotations are not diagnostic for Lyme disease or a measure of systemic organism burden, the coherence of these signals—together with previously peer‑reviewed findings of increased fecal short‑chain fatty acids, notably butyrate, and reductions in Spirochaetes—provides a compelling rationale for controlled trials (as previously reported in a 2024 peer‑reviewed paper).

“Across studies we’re seeing a butyrate‑forward profile emerge alongside declines in spirochete signals,” said Dr Rosemary Waring, Science Officer and Co‑Founder, Tharos Ltd. “That’s scientifically exciting because butyrate is central to gut homeostasis. The responsible next step is to test this signal—rigorously—under blinded, controlled conditions.”

Key signals from the pilot (facts) Design: Uncontrolled, before‑and‑after pilot over ~4 weeks in 4 horses and 16 dogs receiving ERME within their normal feed.

Sequencing readout: Baseline vs. follow‑up stool samples underwent 16S rRNA gene sequencing with genus‑level taxonomic annotations.

Directional change observed: In a subset of animals, relative abundance of reads annotated to Borrelia declined from baseline to follow‑up. These measures do not diagnose Lyme disease or establish organism viability or tissue burden; interpreted alongside prior increases in short‑chain fatty acids—especially butyrate—and reductions in Spirochaetes, the pattern is encouraging and warrants controlled investigation.

Use history & tolerability: ERME (EquiNectar/CaniNectar) has been commercially available since 2018 and well tolerated in routine use and in this observational pilot. As of July 2025, over 2,000 horses are reported by company records to use EquiNectar regularly.

Next step: controlled trials Tharos is advancing controlled, blinded protocols with independent veterinarians to test preregistered endpoints (e.g., laboratory markers, owner‑reported outcomes, and blinded assessments) and to publish methods and analyses. Collaborators are invited to contact hello@equinectar-usa.com to participate in study design, power calculations, and site selection.

Quality and certifications (horses) EquiNectar® production and supply operate under recognized United Kingdom feed‑assurance certifications for the equine sector, including UFAS, FEMAS, and BETA NOPS. These schemes address feed materials quality, supply‑chain integrity, and controls on naturally occurring prohibited substances; they are not approvals for medicinal use or claims of efficacy.

What ERME is — and is not ERME (EquiNectar/CaniNectar) is an animal feed supplement intended to support normal digestive function in animals.

It is not a veterinary drug and is not intended to diagnose, treat, cure, or prevent any disease.

References to Borrelia, Spirochaetes, and SCFAs are provided for scientific context only and do not imply effects on infection, symptoms, or clinical outcomes.

Background: Lyme disease and the Borrelia bacteria What it is. Lyme disease (Lyme borreliosis) is a tick‑borne infection caused by spiral‑shaped bacteria in the Borrelia burgdorferi complex. The dominant species vary by region (e.g., B. burgdorferi in North America; B. afzelii and B. garinii are also common in Europe).

How it spreads. Transmission occurs through the bite of hard‑bodied Ixodes ticks (e.g., I. ricinus in Europe, I. scapularis in North America). Ticks acquire Borrelia from wildlife reservoirs; effective attachment and feeding over many hours is generally needed for transmission.

Dogs and horses. Exposure is not uncommon in outdoor animals; many exposed (seropositive) animals remain clinically normal. When illness occurs in dogs, reported signs can include shifting‑leg lameness, joint pain, fever, and lethargy; kidney complications are uncommon but recognized. In horses, clear clinical disease is considered less common; reported signs include stiffness or lameness, poor performance, behavioral changes, weight loss, and, in some cases, ocular inflammation. These signs are non‑specific.

Diagnosis. Veterinarians interpret clinical signs with exposure history and laboratory testing. Serology (e.g., C6 assays) can indicate exposure; PCR or culture from appropriate tissues can provide direct evidence but are not routine. Stool microbiome assays are not diagnostic for Lyme disease in animals.

Spirochetes: context for microbiome signals What they are. Spirochetes are corkscrew‑shaped bacteria (phylum Spirochaetota) that include pathogenic genera such as Borrelia (Lyme borreliosis), as well as other genera (e.g., Treponema) that can be present in gut communities. In healthy horses, the fecal microbiome is typically dominated by Firmicutes and Bacteroidetes, with many other phyla, including Spirochaetes, occurring at low relative abundance.

How to read stool‑based “spirochete signals.” Relative abundance measures from 16S rRNA sequencing reflect luminal community composition, not organism viability or tissue burden. Genus‑level annotations (e.g., reads labeled Borrelia) are low‑abundance and not diagnostic for Lyme disease; they are best interpreted as exploratory markers that may move alongside broader microbiome shifts (see “Notes to editors” for caveats).

Why a reduction can be encouraging (pattern‑level). In peer‑reviewed equine and canine studies, supplementation was associated with lower Spirochaetes together with increases in SCFAs—especially butyrate—and higher relative abundance of butyrate‑producing taxa (e.g., Blautia, Oscillospira). Considered together, this butyrate‑positive, spirochete‑down profile is often viewed as favorable for gut ecology and warrants controlled follow‑up; these observations remain non‑diagnostic and non‑medical.

Why butyrate matters (background) — expanded What butyrate is. Butyrate is a short‑chain fatty acid (SCFA) produced by certain gut bacteria during fermentation of dietary carbohydrates. In mammals, it is a primary energy source for colonocytes, helping maintain epithelial energy balance and a low‑oxygen lumen that supports beneficial anaerobes.

Why it’s considered beneficial (non‑medical context):

Barrier & mucus: Associated with support of normal barrier function and healthy mucin production in the gut lining. 

Immune tone/homeostasis: Through GPCR signaling (FFAR2/FFAR3, GPR109A) and epigenetic effects, butyrate has been shown in preclinical models to promote regulatory pathways and temper excessive NF‑κB signaling, consistent with a balanced mucosal environment. 

Motility & comfort: SCFAs, including butyrate, can influence normal colonic motility and visceral sensitivity in animal studies; veterinary relevance is an active research area. 

Microbial ecology: A butyrate‑forward profile often coincides with higher relative abundance of butyrogenic taxa (e.g., Faecalibacterium, Roseburia, Blautia) and cooperative cross‑feeding with acetate‑producers—patterns linked to community stability and lower luminal pH.

Contextual note: These are physiology‑focused observations; they do not imply diagnosis, treatment, cure, or prevention of disease.

What prior work showed. Eight‑week supplementation studies in leisure horses and dogs reported increases in fecal SCFAs (equine mean total 1,376→2,077 ppb; butyrate 335→405 ppb), reductions in Spirochaetes, and higher relative abundance of butyrate‑producing taxa (e.g., Blautia, Oscillospira), alongside shifts in volatile metabolites; 9/10 dogs showed increases in beneficial SCFAs.

By the numbers (from prior peer‑reviewed work) Equine SCFAs (mean, ppb): total 1,376→2,077; butyrate 335→405; acetic 505→737; propionic 533→938 (8 weeks).

Dogs: 9/10 showed increases in beneficial SCFAs (butyrate, acetate, propionate) after supplementation; decreases in at least one “toxic” metabolite (ammonia, methanol, ethanol) were also observed.

Racehorses (training): Dietary amylase‑rich malt extract significantly altered the fecal volatile metabolome; the community remained Firmicutes/Bacteroidetes‑dominated with small but significant microbial shifts.

Notes to editors Use history: First year on sale 2018; as of July 2025, >2,000 horses are regular users of EquiNectar® (company records).

Limitations: The current pilot was small, uncontrolled, and not blinded; stool 16S data provide relative, not absolute, abundances and cannot establish organism viability or tissue burden. Temporal associations may reflect natural variability or confounding.

Context from prior research: Leisure horses/dogs (8 weeks): increased fecal SCFAs (including butyrate) and lower Spirochaetes; higher Blautia/Oscillospira in horses; 9/10 dogs with higher SCFAs. Racehorses (6 weeks): decreased fecal SCFAs post‑supplement interpreted as enhanced pre‑caecal digestion and altered substrate delivery; marked VOC shifts with small but significant microbiome changes. Sanctuary horses (6 weeks): ERME group showed significantly lower acetate, with authors suggesting better colonic SCFA absorption as a possible explanation; metabolome altered by both pasture and supplement.

Terminology: “Reads annotated to the genus Borrelia” refers to short‑read 16S rRNA gene sequences assigned at genus level; such annotations are not validated biomarkers for exposure, infection, or treatment response.

About Tharos Tharos Ltd is UK‑based with a growing US operation in Greenacres, Florida, exploring nutrition‑centric approaches to animal gut health. The company partners with academic and veterinary groups to advance transparent, data‑driven research and open protocols.

Media contact:

Dr Rosemary Waring, Science Officer

hello@equinectar-usa.com | (844) 435 1894

Disclaimer:

ERME (EquiNectar/CaniNectar) is an animal feed supplement intended to support normal digestive function. It is not intended to diagnose, treat, cure, or prevent any disease. Any forward‑looking statements in this release are based on current expectations and are subject to risks and uncertainties; actual results may differ.

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