The strange family matters of the common chicken
The chicken is the most common bird in the world, and the most common breed has the most complicated family of all.
Chickens are the most common bird in the world and they have a complicated family tree.
The types of poultry and the terminology used by those in the chicken world can be confusing, especially if you’re new to it.
What you really want to know is what types are available and which ones would be best for your situation. But you may then start to wonder why this family of animals is so different, and what is behind the various breeds.
The domesticated fowl is officially, scientifically, known as Gallus gallus. All the breeds in the world are believed to originate from the Red Jungle Fowl which was domesticated about 5000 years ago.
However, in 2008, genetic research of the skin colour of chickens showed there was also another species mixed up in this chicken soup, probably the closely-related Grey Junglefowl which carries the genes for yellow skin that is common in the domestic birds we see today.
What the terms mean Poultry: can refer to the fowl species – the domestic chicks, pullets and adults we have in our flocks – but can also encompass the duck, goose, turkey and guinea fowl species when talking generally.
Chicken: technically refers to the youngng fowl, but is today also commonly used as a generic term to cover all age groups.s. Some also argue it should only be used to refer to end-product, eg chicken is a meat, eat, while poultry is the correct term for fowl wl that is living.
Hen: an adult female fowl, usually over one year old and in her second laying season.
Pullet: a juvenile female fowl from hatching to her first laying season, which can vary from the start of physical al maturity to after her first year.
Cock/rooster: a mature male usuallyy over one year old.
Cockerel: a juvenile male from hatching until maturity at around one year old, which can vary from start of physical maturity or after first year. Heritage breeds* These are often classed as the ‘pure breeds’, as outlined in the official breed standards which is updated from time to time as new colour/forms are stabilised.
Breeds can be grouped into birds of similar size. *NB some breeds listed are not currently present in NZ or do not have full recognition by the NZ Poultry Association; many have a range of colours and feather patterns within the standard type. Heavy Breeds as per NZ Poultry Standards Most of the heavy breeds were developed in America and the UK and lay buff to brown eggs. The statement that birds which have red ear lobes lay brown eggs is often quoted but ‘brown’ can vary from rich brown to pale beige. Australorp, Barnevelder, Brahma, Chinese Langshan, Croad Langshan, Cochin, Dorking, Faverolle, Frizzle, Maran, North Holland Blue, New Hampshire Red, Orpington, Plymouth Rock, Rhode Island, Sussex, Wyandotte Hard feathered breeds This includes game birds, some of which may have a bantam version. Old English Game, Modern Game, Indian Game, Malay, Asil
Light breeds as per NZ Poultry Standards Many of these are of Mediterranean origin, although the Silkie is of Asian origin. Most lay white eggs, but some can tend to cream, and the Araucana lays blue eggs. Most light breeds have white ear lobes, but those of the Silkie can be turquoise blue or mulberry (dark red). Ancona, Andalusian, Araucana, Campine, Hamburg, Houdan, Legbar, Leghorn, Minorca, Polish, Sicilian Buttercup, Spanish, Silkie, Welsummer Bantams These are smaller versions of many of the standard breeds, including the Game breeds, but there are also some breeds which are ‘true bantams’ with no larger versions True Bantams as per NZ Poultry Standards Japanese, Pekin, Rosecomb, Sebright, Belgian Bearded, Booted, Dutch The most common birds in the world The world’s average stock of chickens is almost 19 billion according to statistics from the UN’S Food and Agriculture Organisation in 2011, and most of them are commercial hybrids.
These are the result of stabilised crosses of various strains and breeds which over the years have been bred to produce a bird with consistent type and performance for economic purposes.
They are the result of crossing two parents of differing strains and this means they cannot be bred ‘true’. For example, if you cross a Shaver Brown hen with a Shaver Brown rooster, you won’t get chicks that show the same reliable traits (eg high laying) as their parents. This is because breeding stock is carefully controlled by the companies which supply these birds to commercial poultry farmers, to prevent theft of their carefully-created ‘brand’. Franchised hatcheries pay a royalty per chick hatched back to the developer – the two big brands in NZ are Shaver and Hyline – which funds ongoing development work and distribution worldwide. In New Zealand there are two commercial layer strains and two commercial meat strains available. Layers: Hyline Brown, Shaver Brown Meat: Cobb White, Ross White These commercial birds are produced under strict franchise situations. A hatchery will import the breeding ‘stock’ as fertile eggs which are then hatched and reared under quarantine as ‘grandparents’. Their chicks are then cross bred to become ‘parents’, and their crossbred chicks become our laying hens and roast dinners.
hybrids do not breed ‘true’
The creation of a layer hen The Grandparent bird may be bred from up to four different strains and each one contributes a different quality to the Parent bird. If the eventual offspring was to be a Shaver Brown or a Hyline Brown then the strains producing the parent roosters may well carry traits such as: • brown feathers from breeds or strains, developed over many years to be birds which carry brown feathering; • consistently laying quality brown eggs with good internal egg quality and shell strength; • good liveability (able to survive the conditions); • a docile temperament; • good feed conversion, efficiently converting feed to eggs.
One set of Grandparent birds (we’ll call them A and B) could be from the same strain or differing strains. Only the male chicks are kept for breeding.
Grandparents C and D will have been selected slightly differently and will supply the female chicks used for breeding.
These will have traits for things like: • good reproductive qualities; • egg numbers; • internal and external egg quality; • small body size; • potential to lay good-sized eggs on minimal feed eaten; • the ability to have long clutch sizes, eg eggs laid on consecutive days; • lack of broody tendencies; • a docile temperament; • the ability to lay over a long season, possibly up to 18 months, before stopping to moult.
These hens will also have genes for brown eggs. These are typically only found in heavy breeds which lay fewer eggs, so the ancestry line for a small, whitefeathered, brown egg-laying breed needs to be developed first.
The results of the matings of Grandparents A&B and C&D will produce male chicks with specific traits and female chicks with different ones. When these Parents are mated together, each will introduce a set of traits which combines to produce a hybrid chick that is better than either of its parents.
Almost all of today’s commercial hybrids are able to be sexed easily at hatching either by down colour or by wing feather development. In the case of the Hyline and Shaver Browns, the males have yellow down, while the girls are brown.
The ability to determine the sex of these chicks on hatching just by looking at their down colour means much cheaper production costs. In the past, these companies used professional vent sexers which examined each bird to determine whether it was male or female, highly specialist work that is not accurate. Using genetics means their customers can be guaranteed (99% or higher) that what they buy are pullets. Hatcheries also always supply more chicks than they are paid for to cover sexing errors and deaths in transport.
The creation of the meat bird The Ross and the Cobb are meat birds (broilers) produced by different companies. A very similar selection process is used as for layer hens, with each parent bringing its own set of traits to the final chick.
The male line selection of traits puts more emphasis in selecting breeding lines developed for: • its ability to grow fast • the dimensions and proportion of meat to the breast and thighs
• conversion of the least feed into the most meat • docility • white feathering so coloured feather stubs do not show on the carcase
• reproductive traits, like fertility
Great grandparent generations may be selected from the very top birds from trial flocks of thousands of birds. These birds are x-rayed to check on leg development, to ensure cartilage is forming correctly, and that the skeletal frame is able to carry the weight of this fast-growing bird.
The female parent of a meat bird needs to be able to lay a reasonable number of eggs. She needs to be laying large eggs quickly, which will then produce bigger day-old chicks, and have some of the growth and meat characteristics of her mate.
She may lay only half the number of eggs that her hybrid laying hen counterpart produces, so to produce lots of broiler chicks economically she will need to have the potential to lay more eggs than the meat sire line and their hatchability needs to be high as well.
The combination of the two parent lines produces a good number of fast-growing chicks, up to 150 per hen in her laying season. The breeders are usually culled at 64 weeks of age after a 40 week laying period.
Careful attention is paid to feed amounts and weight gains for these specially selected meat parents. Even so they will probably lay more eggs and grow far more efficiently than some of the large heritage breeds from which they were developed.
It’s a difficult process because genetic selection for growth/meat is counterproductive to reproduction traits, eg the bigger the bird, the less eggs it will lay. The same applies in meat animals such as cattle, where selection for milk production in cows, and the ability to get in calf early and annually, is the opposite to that of beef cattle which grow fast and
Meat birds look very different to layers, but similar processes are used to get a bird that grows big and fast.
muscular, produce less milk, and are later to mature.
Once chicks are hatched, it’s often important to separate the boys from the girls. You always want your KFC drumsticks to be same size, and male and female meat chickens grow at different rates, so are often reared separately so a farmer can guarantee a consistent size of bird.
Red Jungle Fowl.
Silver Laced Wyandotte.
Old English Game hen.