How important is food structure when cats eat mice?

Area of Science:

• Veterinary Nutrition
• Animal Microbiology
• Gastroenterology

Background:

• Whole prey diets are anecdotally linked to improved gastrointestinal health in felids.
• The specific factors (chemical vs. physical) driving these benefits remain unclear.
• Domestic cats serve as a model for strict carnivores to study dietary impacts.

Purpose of the Study:

• To investigate the effect of food structure (minced vs. whole prey) on cat gut health.
• To compare the digestibility, nitrogen excretion, microbial activity, and fermentation products of different diets.
• To understand the shift in intestinal microbiota composition in response to diet changes.

Main Methods:

• Fifteen domestic cats were fed either minced mice (MM) or whole mice (WM) diets.
• A crossover design was used, with an initial period on a commercial extruded diet (EXT).
• Faeces and urine were collected for analysis of digestibility, nitrogen excretion (using 15N), microbial activity, and fermentation products (SCFA, BCFA, BA).

Main Results:

• Food structure (minced vs. whole) did not significantly alter large intestinal fermentation parameters like SCFA, BCFA, or most BA.
• Transitioning from EXT to mice diets induced a significant shift in microbial community from carbolytic to proteolytic profiles.
• This dietary shift led to reduced faecal acetic to propionic acid ratio, SCFA, BCFA, NH3, total BA, and para-cresol.

Conclusions:

• The overall diet type (extruded vs. whole prey) is more critical for cat gut health than the physical structure of the prey.
• Prey-based diets induce significant beneficial shifts in the feline gut microbiome and reduce potentially harmful fermentation products.
• Careful consideration of prey-based diet composition is essential for optimizing gut health in cats.