Agent Starling was traumatized by lambs led to the slaughter in the film “The Silence of the Lambs.” For pet owners likewise concerned by the livestock industry, cell-cultured meats provide a means of serving muscle tissues with no ethical issues. Lamb protein, grown using genetically engineered yeast, may be one of those upcoming animal alternatives. In an experiment, scientists used precision fermentation to grow enough of those transgenic yeast to create a “brewed lamb protein,” then served food made with the protein to a group of dogs.
“Digestibility was similar among all study foods, except that fat digestibility was lower in foods with the test ingredient,” the researchers wrote in the journal Animals. “Altogether, these results indicate that the test ingredient is safe for use in dog food.”
Brewed lamb protein offers sustainable novel pet food ingredient
In the study, 40 healthy adult dogs were allocated to diets containing 0 % (control), 15%, 30% or 40% brewed lamb protein (substituting for egg protein) over 182 days. The scientists measured body weight, body condition score, body composition, food intake, blood chemistry, urinalysis and fecal/intestinal markers. A parallel digestibility trial (14-day adaptation + 5-day collection) was conducted with another set of dogs to assess apparent and true digestibility of macronutrients.
Across the board, dogs tolerated the ingredient well: no significant changes in weight, lean vs. fat mass, body condition or food intake were observed. Hematology and serum biochemistry largely remained within reference ranges, with a few statistically significant shifts (e.g. lower chloride, cholesterol, homocysteine, and whole-blood taurine in some test groups), but still within normal limits. Urinary parameters and other markers proved unremarkable. Fecal pH decreased (consistent with greater fermentable fiber) and fecal scores were slightly softer at higher inclusion rates, though still acceptable on the Hill scale. Digestibility of protein and dry matter was unaffected, but fat digestibility declined modestly in parallel with inclusion level.
The study results suggest that brewed lamb protein could serve as a novel protein-alternative in dog diets, helping to diversify protein sources and reduce reliance on traditional animal agriculture. Because the yeast remnants remain with the ingredient, manufacturers may also capture the beneficial fiber and beta-glucan effects associated with yeast.
For pet food formulators, cell-cultured lamb could become another protein in the palette, if formulation, cost, scale and regulatory hurdles can be addressed.
Tim Wall | DALL-E
