Sweetcorn is much loved by rabbits and guinea pigs but it is fattening and has a very inverse Ca.P ratio with a calcium level of only 2mg and a phosphorous level of 89mg per 100gm. That same 100gm does at least provide 6.8mg vitamin C, just a little more than 100gm of carrots.
However it is a useful winter food for animals kept in sheds or outdoor hutches when balanced with calcium rich foods that have a good Ca:P ratio.
The silky fronds which lie between the corncob and the protective outer leaves are known as cornsilk and used as a herbal medicine for the urinary tract. The outside leaves of the corn cob, if free from contamination with mould, make a fibre rich treat. The leaves of the plant and the stem can also be given.
In addition to being fattening, sweet corn has been implicated in gut blockage in rabbits so it is very important to feed only small amounts of sweetcorn as a treat.