Name the pictured chicken breed.

The chick has been modified as an embryo to be sterile, but as it develops the scientists inject 'primordial germ line' cells from rare chicken breeds.

Farmers use slow-growing chicken breeds and a maximum of 15 birds per square metre are allowed, compared with the 18 or 19 birds in standard production.

The program has since become the template for similar programs focusing on the preservation of other rare chicken breeds.

They molt every other year, unlike most chicken breeds that molt every year.