Leghorn is an exotic breed of:

Leghorn is an exotic or foreign breed of poultry.

Exotic breeds

The exotic breeds that are not native to that place. Brown Swiss and Jersey Swiss are the exotic breeds of cow. Exotic breeds are used for cross-breeding. Many exotic cattle breeds were brought to India for cross-breeding and upgrading to improve milk production potentiality in our cattle. A higher growth rate normally characterizes exotic breeds, ensuring that their productivity is very high. Exotic breeds are often considered more efficient because the interaction with the new environment is not taken into account, or it is artificially controlled unsustainably.