It comprises an egg preparation comprising a mixture of the yolk and the white extracted from a fertilized egg incubated for a period comprised between 18 hours and 36 hours, wherein the mixture of the yolk and white is in a ratio in which the amount of the white is comprised between 2% and 40% by volume of the yolk volume, useful as regenerating, analgesic and/or anti-inflammatory agent, as well as its preparation process. It also relates to functional foods, dietary supplements, and pharmaceutical or veterinary compositions containing the egg preparation. It also relates to cosmetic compositions comprising the egg preparation and to its use as skin care or hair or fur care agent.