Marmite is the brand name for two similar food spreads: the original British version, since 2000 a Unilever product; and a modified version produced in New Zealand by Sanitarium Health Food Company and distributed in Australia and the Pacific.
Marmite is made from yeast extract, a by-product of beer brewing. Other similar products include the Australian Vegemite (saltier in taste), the Swiss Cenovis and the German Vitam-R.
So can rabbits eat marmite at all?
Unfortunately they can eat at all. It is just too bad for them to eat and full of folic acid and yeast extract. It will hurt them if they eat it.