UPDATING ABNORMAL MILK TESTS

Abstract

The U. S. Public Health Service and the National Conference on Interstate Milk Shipments have agreed to require that producers meet standards for the abnormal milk program. Effective July, 1, 1970, all raw milk shall contain less than 1,500,000 leucocytes per milliliter. The regulations of various states now require that qualified personnel in approved laboratories make total bacterial plate counts on all raw supplies at least once a month. A proposed modified direct microscopic somatic cell count can effectively be used as a rapid screening test by the same personnel, eliminating the need for other screening tests. This procedure also utilizes low power “spotting” to detect clustered leucocytes with enmeshed bacteria to establish the presence of bacterial mastitis. When these clusters are found, the need for counting leucocytes is eliminated. Photographs of clustered leucocytes with enmeshed bacteria under low and oil immersion are shown. Typical epithelial cells are photographed. The proposed procedure is advocated because it is accurate, not time-consuming, and can establish the presence of bacterial mastitis.