Phagocytosis by somatic cells from dry cow secretion

Independently of medium in which the process occurred, serum or PBS, phagocytosis and killing of Staphylococcus aureus by somatic cells from dry cow secretion were significantly higher at the early dry period than at the steady state period. Total bacterial survival was highly correlated with phagocytosis and with intracellular survival. Correlations between phagocytosis and intracellular survival were much lower. Percentage of S. aureus phagocytosed after incubation in bovine blood serum showed highly significant variation among samples of cells isolated from secretion of different cows at the early dry period and significant variation among samples of cells isolated from different cows at the steady state period.