Improving fiber digestion in cattle
Unlock energy in forage.
Gilly makes a prebiotic feed additive that helps cattle digest more fiber — turning ordinary forage and low-cost byproducts into more milk and meat, while improving feed efficiency and lowering cost for producers.
Backed by
How it works
A boost for the rumen's own fiber-digesters.
A cow's rumen depends on a small group of anaerobic gut fungi (Neocallimastigomycota): they make up only a small percentage of the rumen microbiome, but contribute about half of plant cell-wall breakdown. Gilly's additive supports these fungi by scavenging residual oxygen to favor strict anaerobes, and by stimulating greater fiber colonization and enzyme output.
Eaten and enjoyed for centuries
Our fungus was traditionally used to make oncom, an Asian fermented food similar to tempeh, and unlike some familiar food molds found in cheese and soy sauce, it makes absolutely zero mycotoxins — one of the cleanest safety profiles of any fermented product.
Fed as a prebiotic
A small amount — under 0.5% DMI — folds into existing feed through the channels producers already use.
More from every bite
The cow draws more energy from the same feed — and from cheaper byproducts most rations can't fully use — so output holds up while feed cost comes down.
Why Gilly
Feed is the biggest cost on the farm. We make it go further.
Gilly typically delivers an approximate 80% return on the producer's spend in added milk and meat value — earning its place in the ration on economics alone, not subsidies or sustainability premiums.
More from the same feed
Feed efficiency improves by up to 3–5% — more milk and meat without changing the ration.
Lower feed cost
A modest daily cost that returns roughly 80% more in milk and meat value.
Use cheaper byproducts
Unlock byproduct feeds like almond hulls and grape pomace in place of expensive forage.
Lighter footprint
Less land, water, and methane per gallon of milk and pound of beef.
Proof
Lab-tested. Farm-bound.
Strong in vitro rumen results
In third party lab testing, our additive improved fiber digestibility (48-hour IVNDFD) by up to 16 points.
Sustained DMI
Palatability established in commercial heifer feeding trials at Trinkler Dairy in Ceres, CA.
University feeding study
A controlled university feeding study measuring milk production and feed efficiency begins January 2027.
Team
Fungal technology meets deep dairy expertise.
Bo Xu
Founder & CEO
PhD at UC Berkeley Plant and Microbial Biology, and founder of Ashby Fungi, a commercial mushroom farm in Berkeley. Leads Gilly's fungal strain development and production process.
Conor McCabe
Ruminant Scientist
PhD at UC Davis in Animal Biology and a Cornell Dairy Fellows alumnus. Leads animal science, trials, and dairy-industry relationships.