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Tridiet-enhanced weight gain in Sprague Dawley rats: a retrospective analysis
Amanda L Rodriguez1, Cameron Bradfield1, Nicholas V Scarpa1
1Malcom Randall Veterans Affairs Medical Center, North Florida/South Georgia Veterans Health System, Gainesville, FL, United States.
Introduction:
Obesity research, including our prior studies, commonly utilizes high-fat (HF) diets to induce weight gain in animal models. Here, we report on outcomes during ad libitum access to a triple (TRI) diet consisting of HF, high-glucose (HG), and standard (ST) chow diets.
Methods:
This retrospective analysis aimed to determine if rats on the TRI diet experienced greater weight gain compared to rats on an HF or ST diet. Previous experimental data from 29 rats were categorized into one of three diet groups: TRI, HF, or ST. Daily food intake and weekly body weights recorded from postnatal days 98 to 182 were analyzed. Caloric intake was calculated based on food consumption and macronutrient composition. Statistical analyses, including confidence intervals and growth modeling, were conducted to assess differences in weight gain patterns across diet groups.
Results:
Significant divergence in body weight emerged early, with differences between the TRI and ST groups evident by 7 days on diet and between the TRI and HF groups by 22 days on diet. TRI rats consumed the highest average daily calories, exceeding both other groups.
Discussion:
For studies focused on developing obese rodents and without specific dietary restrictions, the TRI diet produces heavier animal models faster, potentially reducing study duration and costs.

