Unlike normal pigs, Enviropigs have been designed to produce their own phytase.

Researchers took a gene responsible for the creation of phytase from an E.coli bacteria and added it to the genetical make-up of a Yorkshire pig.

To make sure the bacterium gene would work in the animal, they combined it with a gene taken from a mouse before inserting it into the Enviropig’s DNA.

In tests, the Enviropig was able to absorb more phosphorous from its feed. Its waste contained less of the potentially toxic substance.