# Investigation of the Digestibility, Fecal Characteristics, and Palatability of Oil Mil By-Products as a Plant-Based Protein Source in Canine Diets

## TL;DR

This study evaluates how well dogs can digest and accept different plant-based protein sources, finding pumpkin press cake to be the most preferred and digestible option.

## Contribution

The study provides new empirical data on the digestibility and palatability of various plant-based protein by-products in canine diets.

## Key findings

- Pumpkin press cake was significantly more accepted by dogs compared to other protein sources.
- Pumpkin press cake had the highest protein digestibility at 85.11%, followed by sunflower and soy press cakes.
- Linseed press cake showed the lowest protein digestibility at 77.52%.

## Abstract

This study investigated how well dogs can utilize different plant protein sources, how these diets affect fecal quality, and how readily the dogs accept them. Eight healthy dogs were fed four diets containing different protein sources: pumpkin press cake, sunflower press cake, linseed press cake, and soy press cake. Acceptance was evaluated using a multiple-bowl test. The results showed a clear preference for pumpkin press cake compared to the other protein sources. However, when potato flakes were added to the diets, no significant differences in acceptance were observed. Regarding protein digestibility, the pumpkin diet achieved the highest values, followed by sunflower and soy, whereas linseed showed the lowest digestibility. Fecal quality also varied depending on the protein source. These findings provide valuable insights into the potential of plant by-products as sustainable and digestible protein sources in canine nutrition and support the development of balanced plant-based dog foods.

This study investigates the digestibility, fecal characteristics, and palatability of plant-based protein sources in canine diets. With an increasing number of pet owners adopting vegan lifestyles for ethical, health, and environmental reasons, the demand for plant-based dog diets has risen. Using plant by-products can also be a practical and sustainable option for feeding pets. This study included eight healthy female dogs fed four different plant-based diets using a Latin square (4 × 4) crossover design, with linseed press cake, sunflower press cake, pumpkin press cake, and soy press cake as protein sources. To measure the acceptance of the protein sources, a five-bowl test was used. The apparent total tract digestibility of the different diets and the fecal quality were compared as well as the acceptability of the individual protein sources. The results showed significantly (p < 0.0001) better acceptance for the pumpkin press cake compared to the other three tested press cakes, whereas the addition of potato flakes changed the acceptance and showed no significant (p = 0.1105) differences between the press cakes. Among the tested diets, the highest protein digestibility was observed for the pumpkin diet (85.11% ± 1.77%), followed by the sunflower (84.23% ± 2.20%) and soy diets (82.35% ± 3.37%), while the linseed diet showed the lowest protein digestibility (77.52% ± 6.04%).