Somatic cell count obtained by Ekomilk Scan® and correlations with other methods of analysis

ABSTRACT: The study aimed to evaluate the equipment Ekomilk Scan® as an alternative to somatic cell count (SCC) in milk. For this individual cow milk samples of various ages and different stages of lactation in northeastern state of São Paulo region were collected. The analyzes performed were divided into variables related to the equipment: repeatability and reproducibility, and variables that could influencing the results as: use of preservatives, temperature, time between collection and analysis, breed and milk composition, besides analysis to relate the Ekomilk Scan® with the standard method-direct microscopy and reference-flow cytometry. As the result, for samples analysis, it shouldn’t be added preservative and these should be conducted on the same day of collection; however, temperature sample did not significantly influence results. Furthermore, Ekomilk Scan® did not show good correlation of results with the method of direct microscopy; however, it was necessary to generate equations for a positive correlation between flow cytometry and Ekomilk Scan®. Therefore, it is concluded that the equipment tested is not accurate but it can be an alternative for SCC monitoring in productive units since it uses calibration equations of results.

摘要：本研究旨在评估Ekomilk Scan®设备作为牛奶体细胞计数（Somatic Cell Count, SCC）检测替代方法的可行性。为此，我们采集了圣保罗州东北部区域内，不同年龄、不同泌乳阶段的个体奶牛乳样。本次检测分析分为两类变量：与设备相关的变量，包括重复性与复现性；以及可能影响检测结果的变量，涵盖防腐剂使用情况、检测温度、采样与检测间隔时长、奶牛品种以及乳成分；此外还开展了Ekomilk Scan®与标准方法——直接镜检法，以及参考方法——流式细胞术（Flow Cytometry）的相关性分析。研究结果显示，乳样检测前不得添加防腐剂，且需在采样当日完成检测，但样品温度对检测结果无显著影响。此外，Ekomilk Scan®与直接镜检法的检测结果未表现出良好相关性；但通过构建校正方程，可实现其与流式细胞术检测结果的正向关联。综上，本试验所用设备本身并不具备精准性，但依托检测结果校正方程，其可作为生产单位开展SCC监测的替代方案。