An unusual breed of pumped up bulls

In 1997, the gene encoding myostatin, a protein that suppresses excess muscle tissue growth, was discovered. By turning off this gene, scientists bred “supermice” - rodents with impressive muscle mass.

A random mutation in the myostatin gene has been trampling Belgian fields since 1807, responsible for the constant production of muscle mass in Belgian Blue cows and bulls. The result of the mutation is a walking “double set” of muscles weighing up to 1.5 tons (80% is lean muscle, practically no fat). Character - calm, milk yield is excellent. They are born by caesarean section and can get stuck in the birth canal.

A mutation transforms English greyhounds into "bull" whippets, such as "Big Wendy" - the most muscular dog in the world.