title: Titrations of mammary tumor virus in fresh and treated R3 milk and milk fractions.
mesh_terms: D000818:Animals; D002499:Centrifugation, Density Gradient; D005260:Female; D005615:Freezing; D008325:Mammary Neoplasms, Experimental / Q000382:microbiology*; D008324:Mammary Tumor Virus, Mouse / Q000302:isolation & purification*; D008722:Methods; D051379:Mice; D008892:Milk / Q000382:microbiology*; D011247:Pregnancy; D014461:Ultracentrifugation