Mammary Neoplasms, AnimalDog DiseasesMammary Glands, AnimalLactationMammary Neoplasms, ExperimentalMilkCaseinsMilk ProteinsBreastPregnancyPancreatic NeoplasmsLactalbuminMammary Glands, HumanLactose SynthaseProlactin9,10-Dimethyl-1,2-benzanthraceneNeoplasmsMammary Tumor Virus, MouseBreast NeoplasmsEpithelial CellsMastitisNeoplasms, Cystic, Mucinous, and SerousPregnancy, AnimalMastitis, BovinePrecancerous ConditionsLactoseEstrogens, CatecholImmunohistochemistryCattleMethylnitrosoureaFibroadenomaRats, Inbred ACIGoatsSkin NeoplasmsEpitheliumNeoplasms, Multiple PrimaryChrysenesAcetyl-CoA CarboxylaseRNA, MessengerHyperplasiaCulture TechniquesMilk SubstitutesKidney NeoplasmsNeoplasms, Second PrimaryNeoplasm Proteins