# Effects of Dietary Supplementation with Whole Lamb Omasum on Gut Health and Metabolism in Shiba Inu Dogs

## TL;DR

Adding whole lamb omasum to Shiba Inu dog diets improves digestion, gut health, and metabolism while promoting sustainability.

## Contribution

This study introduces whole lamb omasum as a novel functional pet food ingredient that supports gut health and sustainability.

## Key findings

- WLO supplementation improved stool consistency and digestion of fat and fiber in Shiba Inu dogs.
- WLO increased serum IgA and T-AOC, indicating enhanced immune and antioxidant function.
- WLO enriched gut microbiota with Bacillota and Blautia, linked to better gut health.

## Abstract

Amid growing concerns about antimicrobial resistance and the imperative for sustainable livestock production, nutritional strategies incorporating natural functional feed additives are increasingly recognized as an important means of improving overall health in companion animals. This study explores whole lamb omasum (WLO)—the sheep’s omasum with its original gastric contents—as a sustainable and functional pet food source. In a short-term trial with healthy adult Shiba Inu dogs, adding WLO to their diet improved stool consistency, enhanced fat and fiber digestion, and boosted key health markers. Additionally, WLO supplementation induced beneficial shifts in blood metabolites and gut microbiota, notably increasing the abundance of Bacillota and Blautia, which are linked to improved gut health. These findings suggest that WLO is a promising functional ingredient for pet food, promoting digestive health, immune function, and metabolism while contributing to sustainability through the use of livestock by-products.

The growing pet economy boosts demand for fiber-enriched functional foods to improve canine gut motility and metabolic health. However, low-bioavailability commercial fibers often falter in high-energy diets. Whole lamb omasum—from grass-fed sheep omasum and gastric contents—repurposes a discarded byproduct for waste reduction and sustainable livestock production. This study evaluated the short-term effects of WLO supplementation on gut health and metabolism in healthy adult Shiba Inu dogs. Twelve dogs were randomly assigned to control or WLO groups in a randomized controlled trial. WLO supplementation significantly reduced fecal scores by 8.91% (p < 0.05), increased apparent crude fat and fiber digestibility by 3.70% and 11.55% (p < 0.05), and elevated serum IgA by 35.79–36.15% and T-AOC by 30.53–35.71% (p < 0.05). Serum metabolome revealed 13 between-group and 8 within-subject differences related to lipid and endocrine modulation. Fecal microbiota analysis indicated enrichment of the Bacillota phylum and Blautia genus (p < 0.05). These findings support WLO as a functional food that enhances gut and metabolic health in small-breed dogs.