title: Studies on the pathogenicity of high- and low-passages of a Marek's disease virus (CPRL II).
mesh_terms: D000818:Animals; D000937:Antigen-Antibody Reactions; D000942:Antigens, Bacterial; D001715:Bird Diseases / Q000276:immunology*; D002645:Chickens; D008381:Herpesvirus 2, Gallid / Q000302:isolation & purification / Q000472:pathogenicity*; D008380:Marek Disease / Q000382:microbiology*; D014774:Virulence
chemical_list: D000942:Antigens, Bacterial