[Pigment in the neurons of some encephalic nuclei in Bos taurus]

Pigment granules without the properties of melanin are present in neurons of several districts (Nucleus ruber, Locus coeruleus, Ala cinerea) in the C.N.S. in Bos Taurus. The distinctive features of this pigment are autofluorescence, specifity of staining with Oil red O, Sudan Black and a strong P.A.S. positivity. The early pigment granules appear about at the end of the first year of life, their amount increases with age. The most rich pigment neurons are in the Nucleus ruber; in the neurons of the Substantia nigra, the pigment is very scanty also in the very old animals.