The red panda is a bamboo eater and its diet is mainly bamboo. During summers, the red panda may feed on fruits, mushrooms, leaves, grasses, roots, fruits, lichens and acorns. Although considered herbivorous, the red panda will occasionally take birds eggs and it is speculated that they may eat mice and birds on occasions. Because the nutrient level of bamboo is so low, the Red panda has a slow metabolism and spends a good part of its day foraging.
Bamboo shoots are more easily digested than leaves, exhibiting the highest digestibility in summer and autumn, intermediate digestibility in the spring, and lowest digestibility in the winter. These variations correlate with the nutrient contents in the bamboo. Red pandas process bamboo poorly, especially the cellulose and cell wall components. This implies microbial digestion plays only a minor role in their digestive strategy.
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To survive on this poor-quality diet, they have to eat the high-quality sections of the bamboo plant, such as the tender leaves and shoots, in large quantities, over 1.5 kg (3.3 lb) of fresh leaves and 4 kg (8.8 lb) of fresh shoots daily. This food passes through the digestive tract fairly rapidly (about 2–4 hr) so as to maximize daily nutrient intake.[22] Red pandas can taste artificial sweeteners, such as aspartame, and are the only nonprimates known to be able to do so.[23]
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More detail on individual food items http://animals.mom.me/red-panda-diet-1844.html
