Selenium (Se) is essential for the normal growth and development of humans and animals (Pilarczyk et al., 2010) and exerts antioxidant action as cofactor of glutathione peroxidase, whose activity was reported to be higher in goat versus cow milk (Debski, Picciano, & Milner, 1987). It also acts on the regulation of thyroid function against heavy metals, protecting the vascular endothelium as selenoprotein P and behaving as an antineoplastic agent as cofactor of thioredoxin reductase The range between the recommended (55 ug/day) and toxic daily intake (400 ug/day) of this element is narrow (Navarro Alarcon & Gil Hernandez, 2010).