A simple, rapid screening test for mastitis in bulk samples has been described. The test is based on the observation that an increase in leucocytes is accompanied by an increase in viscosity when a detergent reagent is mixed with a milk sample. The viscosity is determined by measuring the height of a column of milk-reagent mixture remaining in a test tube after a 15-sec outflow through a cap having an orifice 1.2 mm dia. The results of this method correlate well with the square root of the leucocyte count (correlation coefficient equals 0.91).
1Supported in part by a research grant (EF AJ 00370) of the Division of Environmental Engineering and Food Protection of the U. S. Department of Health Education and Welfare, Published with approval of the Director of the Wisconsin Agricultural Experiment Station NS-426.
2Official laboratory for the Wisconsin State Board of Health.