Investigating the effects of supplementing a polyphenol blend on oxidation, inflammation, energy metabolism and colonic fermentation in healthy adult male cats

Polyphenol-containing ingredients are increasingly added to commercial pet foods, yet controlled feline research remains limited. Conifer bark is a renewable lumber industry byproduct and a sustainable polyphenol source that has not yet been evaluated in cats. This thesis investigates the effects of a commercial conifer bark polyphenol blend on feed acceptance, oxidation, inflammation, energy metabolism, and faecal fermentation in healthy adult male cats. The blend was well tolerated at 0.02% and 0.04% of the diet, with feed intake suppressed at 0.2% and 0.4%. After 28 days of supplementation, there were no effects on serum oxidative and inflammatory markers, energy expenditure, or respiratory quotient. Faecal propionate and valerate concentrations were greater at 0.04% than 0.02% of the diet, though neither dose differed from the unsupplemented control. Overall, this study provides foundational research in healthy cats, for future conifer bark polyphenol studies to build upon.