Most rodent and lagomorph species do well on diets based on commercial laboratory rodent pellets or rabbit pellets. Rabbits, hares, pikas, marmots, and prairie dogs can be maintained on rabbit pellets, alfalfa or grass hay, and a limited amount of assorted vegetables (note that in some cases, feeding high amounts of alfalfa caused urinary problems in pet rabbits and guinea pigs). Most other sciurids (squirrels, chipmunks, and marmots) can be fed rat pellets and a limited mixture of sunflower seeds, millet, corn, and rolled oats. Ground squirrels can also be offered a limited amount of green and leafy vegetables, in addition to hay and a suitable pellet. Most murids, cricetids, gophers, dormice, and jerboas do well on rat pellets; for smaller species, mouse pellets, a seed and grain mix, green leafy vegetables, carrot, and apple can be fed.
Hay should be made available to voles and lemmings. Captive voles may be difficult to manage unless a high-fiber rabbit pellet is used. Muskrats, agoutis, and capybaras will eat a combination of rat and rabbit pellets along with alfalfa hay, carrot, and apple. Porcupines can be fed rat pellets, rabbit pellets, and dry dog food in equal portions; evergreen (willow) branches should be made available whenever possible, as should bones for gnawing. Beavers can be fed with herbivore (primate) pellets, regularly augmented with willow, poplar, aspen, or alder branches. Feeding a large amount of alfalfa and pellets containing high levels of calcium is not advised, because it can lead to urolithiasis in some rodent and lagomorph species.
Guinea pigs and capybaras cannot produce their own vitamin C, so they should be offered commercial guinea pig pellets (fortified with vitamin C) instead of rabbit pellets, along with greens. Capybaras have reportedly developed gum disease and clinical signs of scurvy when vitamin C is lacking. Therefore, they can be fed leaf-eater pellets and guinea pig pellets, in combination with leafy vegetables and browse (hay). While guinea pigs are known to require a dietary source of vitamin C, other lagomorphs and rodents also may benefit from it.
Also see the discussions of husbandry for specific rodent species and nutrition of rabbits.
