Standard Plate Count - The Standard Plate Count (SPC) is one of the oldest and most frequently used methods for enumerating bacteria. The SPC, employing uniform standardization of equipment, materials, and incubation is of considerable value because it determines the quantity of aerobic bacteria per sample tested. High SPC results indicate cows infected with mastitis or poor cow preparation which means unsanitary milking and cleaning protocol.
Laboratory Pasteurization Count - The Laboratory Pasteurization Count (LPC) is performed in the dairy testing laboratory to detect high levels of thermoduric ( pasteurization- resistant) bacteria in raw milk supplies. These bacteria are not known to be pathogenic for man, but at high levels will affect the grading quality of Grade A pasteurized milk produced. The organisms readily resist pasteurization methods, thereby causing high bacterial counts in violation of the accepted bacterial standard. The principle sources of contamination are poorly cleaned and sanitized utensils and equipment on farms and in processing plants. The thermoduric count has been used in the dairy industry primarily as a test of care employed in utensil sanitation.
Coliform Count - Coliform bacteria are almost uniformly present in raw milk. The extent of their presence at the time milk is received at the plant is dependent largely upon the sanitary conditions under which the milk has been produced and upon extent of growth of these bacteria between the time of milking to the time of delivery to the pasteurization plant. Even under the best of conditions a few coliforms almost always can be found. One of the most damaging types of mastitis may be caused by certain coliform types. However, improperly cleaned utensils are the most common source. The exterior of the cow may contribute some of these bacteria, owing to contact with fecal material.
Somatic Cell Count - Mastitis involves the inflammation of the tissues of the udder by specific pathogenic bacteria and, sometimes by several bacterial types at one time. Detection methods include the Somatic Cell Count (SCC). Leucocyte counts are made by observing stained milk smears under 1000 x magnification and counting the total number of leucocytes (present during mastitis infection) in the appropriate number of microscopic fields. The greater the number, the greater the mastitis infection is. early detection is important for the sake of milk production and for the health of the cow.
By keeping the equipment and processing plant properly sanitized, most of these organisms can be avoided. If you have any questions regarding this newsletter or would like more information on our tests, please call us at (909) 947-6065.