Despite the development of hypoxic-ischemic encephalopathy in calves with perinatal asphyxia, the lack of expected increase in serum GFAP concentrations may be related to the fact that GFAP is usually found in astrocytes and their structure is not broken down unless severe damage occurs [67], and therefore, GFAP is not released sufficiently into the bloodstream. Here, GFAP is linked to perinatal asphyxia.