At the requests of our Russian and international customers parallel testing of our viscosimetric Somatic Cells analyzer Somatos Mini and DeLaval electronic Cell Counter DCC which is based on the method of direct counting of cell number has been conducted by our laboratory.
For the analysis on DCC electronic Cell Counter a sample of milk is drawn in to a disposable cassette, the milk sample is mixed with a reagent that stains the somatic cells nuclei. After that the cassette is inserted into the DCC counter inside of which there is a fluorescent microscope, using optical measurements DCC calculates the exact number of somatic cells in 1 cm3, and the result of the analysis is displayed on the instrument’s display. The convergence of measurements for this method, according to the estimates of DeLaval specialists is up to 12% at 100 thousand cells / ml and up to 7% at 1 million cells / ml.
For the analysis on Somatos Mini Somatic Cells Analyzer tested milk sample is mixed up with a special chemical preparation (Mastoprim), the viscosity of this mixture depends directly on the number of somatic cells in the milk, the mixture flows through a special capillary, the analyzer counts the time of the outflow of the mixture and the corresponding number of somatic cells.
For the comparative testing of the analyzers 7 samples of fresh milk were selected with a content of somatic cells from 90 thousand to 1300 thousand cells evenly distributed over this range.
Each sample was tested in triplicate on Somatos Mini and concurrently on DCC somatic cell counter, the results of comparative tests showed high convergence of the measurement results of these two devices. Relative error of Somatos Mini is not more than 5% that meets the declared specifications/ data sheet).
Test data showed:
- In the range of more than 1000 thousand cells DCC counter behaved better, since when testing milk with high somatic number on Somatos Mini stagnation effects of milk with high viscosity in the analyzer’s flask can be observed as well as the interruption of the milk jet that does not allow obtaining a more accurate result. However, the results of measurements on Somatos Mini immediately help to identify such milk as milk with high SCC/ non-sort or unusable.
In the range from 90 to 1000 thousand cells, both analyzers DCC cell counter and Somatos-Mini analyzer showed results with high convergence.
Parallel testing of Somatos Mini and DeLaval electronic Cell Counter DCC were conducted with the participation of DeLaval representative, Mr. Alexey Klimov.
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