Patent ID: 6979550

Claim:
A method for identifying the presence or absence of mastitis and if present, the stage of mastitis in a lactating animal comprising the steps of obtaining a sample of milk or blood from the animal; isolating leukocytes from the sample of milk or blood; measuring phagocytic ability of phagocytes together with at least one indicator selected from the group consisting of: differential leukocyte counts, leukocyte cell surface antigen fluorescence for CD2, leukocyte cell surface antigen fluorescence for CD3, and leukocyte cell surface antigen fluorescence for CD11b, wherein the differential leukocyte count defines a relationship between cells selected from the group consisting of lymphocytes, macrophages and polymorphonuclear cells, wherein antigen fluorescence for CD2, CD3 and CD11b is obtained by binding of specific affinity molecules having fluorescent labels thereon, wherein a negative control comprising lymphocytes is used in determining the phagocytic ability of phagocytes; and comparing the measured indicators to predetermined ranges for said indicators for early stage mastitis, late stage mastitis and no mastitis, thereby identifying the absence of mastitis or the stage of mastitis in the animal at a confidence interval of greater than or equal to 90%.