correlation was greater than 90 % between feline leukemia virus ( felv ) , group-specific antigen ( gsa ) in leukocytes , and viral infectivity ( vi ) in serum or plasma from 132 cats infected with either the rickard strain of felv , the snyder-theilen strain of feline sarcoma virus , or field strains of felv .
C0229671
serum
C0032105
plasma