Estimating Somatic Cells in Milk Samples by the Membrane-Filter-DNA Procedure.

Area of Science:

• Dairy Science
• Analytical Chemistry
• Biotechnology

Background:

• Somatic cell count (SCC) is a critical indicator of milk quality and udder health.
• Current methods like direct microscopic somatic cell count (DMSCC) have limitations in precision and potential for technician bias.
• Advancements in DNA-based methods offer potential for improved accuracy in SCC determination.

Purpose of the Study:

• To describe further developments in the membrane-filter DNA procedure for milk somatic cell content analysis.
• To statistically compare the membrane-filter DNA test with the direct microscopic somatic cell count.
• To establish a standardization method for the membrane-filter procedure.

Main Methods:

• Development and refinement of the membrane-filter DNA assay for milk samples.
• Statistical comparison between the membrane-filter DNA test and direct microscopic somatic cell count.
• Utilization of lyophilized bovine somatic cells on membrane filters for standardization.

Main Results:

• A quantitative relationship was established: 0.093 absorbance units per million cells at 490 nm.
• The membrane-filter DNA technique demonstrated higher precision compared to the direct microscopic count.
• The membrane-filter method is not susceptible to technician bias, ensuring greater reliability.

Conclusions:

• The developed membrane-filter DNA procedure provides a more accurate and reliable method for somatic cell content determination in milk.
• Standardization using lyophilized bovine somatic cells ensures consistent and comparable results across different laboratories.
• This improved method contributes to better milk quality assessment and dairy herd management.