The phrase "were bred" means to produce offspring through genetic selection. Some synonyms that can be used in place of this phrase include "were propagated", "were reared", "were raised", and "were reproduced". "Propagated" refers to the process of reproducing plants or animals through breeding or cloning. "Reared" refers to the process of raising and caring for offspring until they reach maturity. "Raised" is similar to reared but it can also refer to the process of breeding animals for their meat or milk production. "Reproduced" refers specifically to the act of producing offspring through sexual or asexual means.