Assessment of Electrical Resistance, Dielectric Constant, Dielectric Loss Factor and SCC for Diagnosis of Clinical and Subclinical Mastitis

Abstract

This study was carried out during December, 2024–February, 2025 at the cattle farm of Lala Lajpat Rai University of Veterinary and Animal Sciences, Hissar, Haryana, India to examine the relationship between various milk quality parameters (Electrical resistance; E.R), Dielectric constant (ε′) and Somatic cell count (SCC) for mastitis detection. Total 982 milk samples were collected from the cattle farm of LUVAS, HISSAR. E.R was measured using Dramiński mastitis detector and SCC was determined using a Lactoscan SCC analyser. Based on SCC values, the samples were classified as healthy, subclinical and clinical. The dielectric constant was measured using the open-ended coaxial probe method. Pearson correlation analysis was performed using RStudio. The results showed that electrical conductivity had a weak negative relationship with both dielectric constant and SCC. In contrast, the dielectric constant at higher frequencies (500-2450 MHz) showed a moderate positive correlation with SCC. However, low-frequency values showed little association with SCC. Dielectric loss factor showed significant correlation with SCC at all six frequencies (54 MHz, 104 MHz, 254 MHz, 500 MHz, 915 MHz and 2450 MHz). Overall, dielectric properties at higher frequencies were found to be more reliable indicators of mastitis. The combined use of electrical and dielectric measurements provided a rapid and non-invasive method for early detection of mastitis in dairy cows. Therefore, the present study was undertaken to bridge this gap by investigating the correlation between electrical conductivity, dielectric constant at multiple frequencies and SCC.