A comparison of food preferences and nutrient composition in captive squirrel monkeys, Saimiri sciureus, and pigtail macaques, Macaca nemestrina

I assessed the occurrence of food preferences in captive squirrel monkeys a nd pigtail macaques and analyzed whether their preferences correlate with n utrient composition. Using a two-alternative choice test, I repeatedly pres ented six Saimiri sciureus and six Macaca nemestrina with all possible bina ry combinations of 12 types of food that are part of their diet in captivit y. The two species exhibited significantly different rank orders of prefere nce. Correlational analyses revealed that the preference ranking of the squ irrel monkeys was significantly positively correlated with total energy con tent, irrespective of the source of energy as neither total carbohydrate co ntent nor protein or lipid content was significantly correlated with food p reference. In contrast, the preference ranking of the pigtail macaques show ed a significant positive correlation with total carbohydrate content and w ith fructose content but not with total energy content of the food items. T hese results suggest that squirrel monkeys are opportunistic feeders with r egard to maximizing net gain of energy, whereas pigtail macaques are not bu t rather seek to meet their requirements of metabolic energy by preferring foods that are high in carbohydrates. (C) 2001 Elsevier Science Inc. All ri ghts reserved.