Cytological evaluation of somatic cells in goat milk: a step toward more accurate udder health assessment

Somatic cell count (SCC) is routinely used to evaluate udder health in dairy animals; however, its interpretation in goats remains challenging. Due to apocrine milk secretion, goat milk naturally contains higher numbers of cells and cytoplasmic particles than cow milk. Moreover, the cellular composition differs: macrophages typically dominate in healthy cow milk, while neutrophils prevail in goat milk even under physiological conditions. These differences make it difficult to apply bovine SCC thresholds to goats. This study aims to characterize the cytological composition of somatic cells in goat milk and to explore its potential for improving the interpretation of SCC values used in mastitis diagnostics. Bulk milk samples from dairy goats at various lactation stages were analysed in a standardized laboratory to determine total SCC. Cytological smears were prepared from the same samples and microscopically evaluated to quantify neutrophils, macrophages, lymphocytes, and epithelial cells. Preliminary observations confirm the predominance of neutrophils, comprising approximately 60–80% of total somatic cells, consistent with previous findings reporting 64% in healthy and 79% in mastitic goats (Shah et al., 2017). Samples with SCC values between one and three million cells per millilitre frequently displayed mixed cytological profiles indicative of physiological rather than inflammatory variation. In contrast, samples exceeding three million cells per millilitre exhibited degenerative neutrophils and decreased macrophage counts, suggesting inflammatory changes. Cytological assessment provides more precise information on mammary gland condition than total SCC alone. Establishing cytology-based SCC reference ranges could enhance the accuracy of mastitis diagnostics in dairy goats and reduce the risk of misinterpreting physiological cell variations as pathological.