Module 6: Food Animals – Poultry



image of two gallus gallus chickensCaption: Gallus Gallus wild chickens.

Domestication of the chicken dates back to at least 2000 B.C.  The domestic chickens’ ancestry can be traced back to four species of wild jungle fowl from Southeast Asia.  However, the Red Jungle Fowl (Gallus gallus or Gallus bankiva) is the most commonly found wild species in the world today and is considered the main ancestor of the domestic chicken.  The chicken belongs to the genus Gallus of the family Phasianidae.  Domestic chickens are simply classified as Gallus domesticus.

The sport of cockfighting had tremendous influence not only in the domestication of the chicken but also on the distribution of fowl throughout the world.  After centuries of selection and breeding for numerous extremes, chickens now exist in many colors, sizes, and shapes.  There are more than 350 combinations of physical features known today.  In 1873, the American Poultry Association was organized for the purposes of adopting standards of excellence and establishing a way of classifying the various breeds.

Although the purebred poultry industry served as the foundation for the development of the commercial industry, the two industries soon developed very different types of domestic fowl.  While the purebred exhibition industry continued to select and breed fowl for standard conformations and plumage colors, the commercial industry developed specialized hybrids for meat and egg production.  Today, the two industries are very different. The purebred fowl of today are basically the same as they were 100 years ago and are mainly raised as a hobby, whereas the commercial poultry industry has developed into a science that produces highly nutritious meat and eggs with extreme efficiency.

Breeds and Varieties

The breeds and varieties of chickens are so numerous that it would be impossible to discuss all of them in detail at this time.  However, a basic knowledge of how to identify and classify fowl may be helpful.  Domestic fowl are divided into classes, breeds, and varieties.

Class: A grouping of breeds according to the geographic area of their origin or to similar characteristics.

Breed: An established group of individuals with similar physical features (i.e., body shape or type, skin color, number of toes, feathered or non-feathered legs) that when mated with others of its own kind produce offspring that have the same characteristics.  The Plymouth Rock breed is a good example.

Variety: A sub-division of a breed. Differentiating characteristics including plumage color and pattern, comb type, and the presence of beards or muffs.  For example, the Plymouth Rock breed is available in many colors - Barred, White, Buff, Partridge, Silver Penciled, etc.  In each, the physical shape and features are the same, but the feather color and pattern differ, which constitutes each as a separate variety.

Some of the more common breeds and varieties of domestic chickens include:image of a new hampshire red

  1. New Hampshire Red (shown on the right) have yellow skin, lay brown-shelled eggs and have orange-red adult plumage. This is a dual-purpose breed which means it has been selected for both a meaty body and to produce eggs.
  2. Rhode Island Red are similar to New Hampshire Reds except they are usually better layers and Rhode Island Reds have deep-red adult plumage.  The chicks of Rhode Island Reds are brown in color.
  3. Barred Plymouth Rock are dual-purpose chickens that have gray and white striped plumage.  The black fluff with a white spot on the tops of their head easily identifies the chicks.  This breed was developed in America during the 19th century.
  4. Cochin are mainly raised as ornamental fowl, but the females are frequently used to naturally incubate and brood the chicks of other fowl.  The Cochin’s origin is traced to China but the big, fluffy balls of feathers as we know them today were further developed in America.  Cochins have feathered shanks and have extremely loose, soft feathers that give them their fluffy appearance.
  5. Cornish were developed as the ultimate meat bird and have contributed to build the vast broiler industry of the world.  The Cornish originated in England.
  6. Leghorn are grandparents of our modern white-egg industry.  Originating in Italy, the Leghorn has a large single comb and is flighty by nature. 

Some of the more unusual breeds and varieties of domestic chickens include the following:

image of a chick with frizzled white feather
  1. Polish is another unusual and beautiful breed.  They have a crested or hat of feathers on top of their heads.
  2. Frizzle (as shown on the right) have a genetic modification that causes the feathers to curl back towards the bird’s head instead of lying naturally.
  3. Naked Neck have a bare neck totally absent of feathers.  This single gene trait affects the arrangement and number of feathers over the chicken’s body.
  4. Silkie is a blue skinned chicken used for ornamental purposes.  Some hybrids have been developed for the live bird market.  This breed of chicken appears to have hair instead of feathers.  This is a genetic trait that causes abnormal texture and appearance of the feathers.
  5. Ameraucana were discovered in South America and are nicknamed Easter egg chickens because of the blue and green eggs they lay.  This is again a genetic modification in which a blue cuticle is applied to the egg.  When introduced to brown egg layers, the result is an olive-green shell; introduced to white egg layers, the result is a blue shell.

Bantams are the miniatures of the poultry world.  The word “Bantam” is the term used to classify the over 350 breeds and varieties of true-breeding miniature chickens.  There are bantams of almost every breed of large chicken, but there are some types of which there is no large counterpart.  Bantams are purebreds raised for exhibition and hobby.  Their small size and numerous shapes, colors, and personalities give them a broad appeal to people who live in urban areas.  This illustration shows two males that were hatched on the same day.  Both are White Wyandotte’s.  The one on the left you see a large fowl and on the left a bantam.  The only difference between them is the size. The bantam is about 1/5th scale.

Commercial Poultry

Over the years, traditional breeds have lost their commercial importance since they are not as efficient at producing meat and eggs. Crossbreeds and hybrid strains have been developed into the modern chickens and turkeys used by today’s industry.

All meat and egg poultry raised commercially have been developed by an international primary breeder company.  These birds have been selected to produce an extremely efficient hybrid line specific for the company’s product lines.  


A company that develops genetic strains of chickens or turkeys with superior traits to help the integrator produce efficient birds for their specific product lines.  It takes these companies about 5-7 years to develop a new line of hybrids for the market.
Top of page