Stereological composition of the liver of biotin deficient and control chicks.

In an ultrastructural and stereological study the livers of 28-day-old chicks, fed either a biotin-deficient or a supplemented diet, were investigated. The biotin-deficient chicks showed the known dermal lesions and were significantly retarded in growth. About 30% less hepatocytic nuclei per unit volume liver were found in the deficient chicks than in the controls. In biotin deficiency mainly the rough endoplasmic reticulum (RER) and the mitochondria were affected. RER was diminished in volume and surface density, whereas in mitochondria only the surface densities of the outer and inner membrane were reduced. The reduction of RER is in agreement with the known reduction of protein synthesis in biotin deficiency.