breeding cross in a sentence

1. A popular breeding cross was with Ibrahim to daughters of Ultimate, a Thoroughbred.
2. In selective livestock breeding cross-fostering can be used to combine desirable genetic qualities such as weight, fat distribution or appearance with environmentally influenced ones such as temperament.
3. When you buy a pot of mums in bloom, you know what the plants look like, but you don't know their chances of surviving the winter, since each variety can be the result of many breeding crosses between greenhouse florist mums and tougher outdoor varieties.
4. It's difficult to find breeding cross in a sentence.