What characteristics might a breeder select for in (i) a cereal crop, (ii) a farm animal?

(i) In a cereal variety, a breeder might select for high yield; disease-, frost- or drought- resistance; early maturation; short straw (simpler to harvest); reduced need for fertilisers; good quality of product (e.g. high in protein); processing qualities (e.g. good for making bread). 

(ii) In a farm animal a breeder may select for high yield (wool, milk, meat); good meat/fat ratio; disease resistance; fertility (more offspring).