In naturally acquired mastitis, milk concentrations of IFN-γ reached up to 20 ng/ml, whereas maximum reported levels of IL-6, TNF-α, IL-1β, IL-8, and TGF-α were about 90 ng/ml, 25 ng/ml, 8 ng/ml, 1 ng/ml, and 0.5 ng/ml, respectively, values that were significantly higher than in milk from healthy udders (76). This evidence concerns the gene IL6 and mastitis.