Guernseys originate from Guernsey in the Channel Islands. The breed first became popular in the 18th Century. The breed is now very popular around the world.

The main advantage of the Guernsey is its high component, golden milk. Research in the US has shown that 60% of Guernseys carry the Kappa Casein 'B' gene, which is advantageous for cheese makers.

Also, more than 90% of Guernsey cows produce the A2 variety of Beta casein in their milk, which is believed to be more healthy for consumers, resulting in lower risk of heart disease.