Weetabix is the british version of the original Australian Weet-Bix and were both invented by the Australian Bennison Osborne.
Weetabix is made from whole grain wheat and the version sold in the United Kingdom has 3.8 g of fibre in a 37.5 g serving (2 biscuits). The product sold in North America has 4 grams of fibre in a 35 g serving. (source wikipedia)
So can gerbils eat weetabix at all?
Yes they can eat it in small amounts in a dry state. They will enjoy eating it.
Just make sure it isn’t served with milk as it will make them sick.
They also can’t eat any sweetened weetabix or that which is flavored.