Cortex
Outermost layer zona Glomerulosa- in ruminants is formed by regular clusters & cords of cells.
These cells are columnar or polyhedral, with cytoplasm that is more acidophilic and less foamy.
Zona intermedia-
Occurs in horse, dog, and cat to a lesser degree in cow, sheep & goat.
It is a transitional zone of small undifferentiated cells.
Zona Fasciculata- consists of cuboidal or columnar cells arranged in radial cords. The cells are often called spongiocytes due to the presence of numerous vacuoles from the dissolution of lipid droplets.
Zona Reticularis - consists of cells disposed in freely anastomosing cords. The cells are similar to those of the zona fasciculata but contain fewer lipid droplets & more lipofuscin; the nuclei are heterochromatic and often pyknotic.
