Provided are compositions and methods for treating, ameliorating and preventing various infections, disorders and conditions in mammals, including genetically-predisposed and chronic disorders, where a microbial or bacterial flora is at least one causative or symptom-producing factor, where exemplary compositions are products of manufacture, a food, a drink, a nutraceutical, a dietary supplement, a formulation, a pharmaceutical or a pharmaceutical preparation comprising at least one or several of: a plurality of isolated, or substantially purified bacteriophages or prophages, or bacteriophage subunits, a milk, a milk product, milk lipid, milk fat globule (MFG) macromolecule, a milk mucin, a milk glycolipid, a milk free glycan, a milk mucin-like glycoprotein, a milk protein, a milk sugar or lactose, a milk fat or butterfat, a milk vitamin. In alternative embodiment, provided are compositions and methods for treating, preventing or ameliorating an infection, for example, an infection in the gastrointestinal tract, or bowel.