Contact Information:

pclauer@psu.edu

Phillip J. Clauer
Senior Extension Associate
4-H Youth and Specialty Poultry
Department of Poultry Science
The Pennsylvania State University

The Avian Egg

The avian egg is a marvel to nature's architecture. A highly complex reproductive cell, it is essentially a very small center of life, a world of its own.

As we know it, the egg is the single most complete food known to man. Versatile and nutritious, it is used every day in the preparation of the most common or the most fanciful meals.

Scientifically speaking, an egg (ovum) is the reproductive cell produced by the female. It remains a single cell until the single cell (nucleus) of the male sperm fertilizes it. Once fertilized, the egg has a full complement of chromosomes and genes to start developing.

What is normally called "an egg" (the chicken egg, for example) is a much more complex structure designed to nourish and protect the embryo growing from the zygote. A vigorous health chick can be hatched from each fertile egg. The egg needs only a warm, humid environment while the embryo is maturing.

Although human nutritional requirements are not the same as those of the chick, they are similar in so many respects that the egg has become a convenient, economical source of many of the essential proteins, minerals, and vitamins necessary to our good health.