A comparative analysis of goat milk quality on Norwegian farms with a focus on somatic cell count and seasonal variation

ABSTRACT: Somatic cell count is used as an indicator of milk quality and udder health in dairy goats, although its interpretation is complicated by noninfectious causes, including seasonality, farm-specific practices, and physiological factors. This study analyzed 868 milk samples from 9 Norwegian dairy goat farms to investigate the interplay between SCC, individual bacterial count (IBC), and milk composition. Samples were collected on 3 occasions during the lactation period (early, mid, and late lactation). The results showed that SCC peaked in the pasture period and then decreased but remained elevated in late lactation. Individual bacterial count showed a positive correlation with higher SCC levels, although this correlation varied significantly across different farms and time periods. The presence of intramammary infections only partially explained the varying correlation between SCC and bacterial counts. This indicates that the relationship between SCC and IBC is influenced not only by infections, but also by management practices, environmental conditions, and other farm-level factors. The study revealed a covariation between SCC and other milk components according to the lactation stage and season. Furthermore, the investigation of factors influencing the interplay between SCC and IBC provides a deeper understanding of SCC as a milk quality indicator in dairy goats.