ABSTRACT
Phosvitin is a yolk phosphoglycoprotein bound to lipoproteins within the yolk granules. Its absorption and utilization during chick embryogenesis is still unclear.
The presence of phosvitin was investigated by immunodiffusion techniques in the watersoluble fraction (WSF) of the yolk during oocyte maturation and chick development and in the embryonic fluids.
The immunochemical analysis showed that phosvitin consists of two components, one of which is detectable during oocyte maturation, while both are shown in the yolk WSF of the incubated egg. The appearance of the second phosvitin component during incubation is probably dependent on granule dissolution, as suggested by the immunochemical and biochemical determinations on the embryonic fluids.