Cat's choose 30% of their calories as protein which is associated with both body composition and circulating metabolites

Abstract

As in other mammals, domestic cats have specific taste preferences that can be influenced by macronutrient composition and physical characteristics of food as well as the presence or absence of specific taste imparting compounds (palatability enhancers). This study investigated the relationship of body composition and food choice and that choice on subsequent metabolomic shifts. Experimental foods were prepared with similar palatability for a population (as evaluated by the ratio of the test food to the total daily food consumed [grams test/(grams test+grams control)] through manipulations of factors independent of macronutrients. These foods with similar palatability preference for the population as a whole were then investigated for intake choice with 27 cats with varying adiposity (mean 24.4% fat, min 7.2%, max 32.2%). Four completely balanced foods were available to the cats at all times. The four foods were: a) a food with 42% of calories from protein, b) 43% calories from fat, c) 52% calories from carbohydrate and, d) intermediate levels of calories from protein, fat and carbohydrate. Cats chose 30.3% of calories from protein (Std Dev 4%, min 24% max 38%). Body composition was associated with the choice of percent calories as protein (p=0.008); lean body mass had a linear negative association (p=0.02), as did fat mass (p=0.04) while there was a positive association for the interaction (p=0.02). Overall cats with high body lean and high body fat showed the highest preference for dietary protein. There was a positive association between the percent of calories as protein and urea cycle metabolites (arginine, n‐acetyl arginine, n‐delta ornithine) while increasing calories from protein were negatively associated with specific metabolites in the TCA cycle (isocitrate, alpha ketoglutarate). There was a negative correlation between percent of calories consumed as protein and that consumed as carbohydrate (r=0.84; p<0.001) with only a slight relationships between either protein or carbohydrate calories and percent of calories consumed as fat (p≥ 0.1). However, there was a positive relationship between protein intake and a number of long chain unsaturated fatty acids (oleate, arachidate and docosapentaenoate). In summary, when given the opportunity to choose between foods which had similar palatability cats chose to consume 30.3% of their calories as protein and had specific preferences related to body composition. These intake preferences were associated with metabolic changes reflecting metabolic shifts.Support or Funding InformationHill's Pet Nutrition, Inc.