This study used thirty-two dogs, which were assigned to a preferred period of 14 days and then assigned to one of the four treatment foods: control (containing no added betaine, no added L-carnitine), control with 0.5% added betaine (Treatment 2), control with no added betaine and 300 ppm added L-carnitine (Treatment 3), or control with 0.5% added betaine and 300 ppm added L-carnitine (Treatment 4). All treatment foods were fed for ninety days. Untargeted blood metabolomic analysis and immune response were measured at the beginning and end of the 90-day feeding trial. Feeding betaine increased single-carbon metabolites while decreasing many carnitine-containing metabolites. Feeding L-carnitine increased many carnitine metabolites, while the combination synergistically influenced the metabolome. The combination of betaine and L-carnitine increased the cytokines released in a Tru-culture system in response to stimulation while numerically decreasing their release when unstimulated. Therefore, the combination of dietary betaine and L-carnitine could have the dual positive effects of reducing cytokine stimulation, controlling inflammation during health, and providing a robust response to bacterial infection.

Renea Creech and Kim Wilson outline the challenges of Chronic Kidney Disease in pets, the irreversible loss of kidney function, and how nutrition can help

The gastrointestinal microbiome comprises trillions of bacteria, and is a vitally important organ with wide ranging effects on pet health: Food impacts the composition and metabolism of the microbiome, as well as the production of postbiotics, which are bioactive end products of microbial consumption of prebiotics. Postbiotics include metabolites of nutrients like fatty acids, amino acids, vitamins and polysaccharides. Also gut bacteria can produce postbiotics from plant antioxidants like polyphenols. A growing body of evidence has shown that influencing postbiotic production may have beneficial effects on pet health. Soluble and insoluble fibers are commonly used sources of prebiotics in the pet food industry, some of these fibers have polyphenols bound to them. Understanding the impact of each fiber type on the microbiome composition, metabolism and postbiotic production provides insights into formulating foods that are optimal for pet health.