Turkens

These bizzare photographs are those of a breed of chicken found in Australia known locally as a 'Turken'. They have almost no feathers on the neck and have a reduction in the number of feather tracts on other parts of their body. This unusual strain of naked neck has a pea comb and lays blue or green shelled egg. In the world of show poultry the name Turken is given to a breed that has a single comb and lays a brown shelled egg. Naked necks are also called a Turkens because the loose red skin on the neck resembles that of a turkey

A pea comb is a three bladed comb, with the blades side by side and the central blade a little higher than the lateral blades. This type of comb resembles an opened pea comb and hence the name for this comb type.

The picture on the left is that of a rooster and the one on the right is a hen. Both sexes have a pea comb and a naked neck, the female lays blue or green shelled eggs and the male carries the gene for blue egg shell colour. The naked neck trait is derived from the Transylvanian naked neck breed and the pea comb and blue egg traits are derived from the Araucana breed from South America. The blue shell colour does not affect the content of the eggs which is no different to the whites or yolks of white or brown eggs.

The naked neck condition, the pea comb and the blue egg shell traits are under the control of genes. In fact these traits are all controlled by dominant genes. Poultry geneticists use upper case O to represent the gene for the blue egg shell trait, upper case P to represent the gene for a pea comb and upper case Na to represent the gene for a naked neck. The recessive genes are represented by lower case letters so the brown or white shell gene is represented by an o, the single comb gene by a p and the fully feathered gene by an na. Poultry, like most living things, carry at least two genes for every trait. An individual that carries two of the same genes is said to be homozygous and an individual that carries one of each type of gene is said to be heterozygous . A bird that has two blue shell genes (OO) or two white shell genes (oo) are said to be homozygous and those carrying a blue and a white shell gene (Oo) are said to be heterozygous. The three genes are all located on the same chromosome - chromosome 1.

The chromosome map above shows the order of the genes on chromosome 1. The blue egg and pea comb genes are so closely linked that they are generally inherited together. A bird which has a pea comb will nearly always lay a blue shelled egg if it is a hen or pass the traits to its offspring if it is a rooster. The naked neck gene and silkie genes are further down the chromosome.

There are suggestions that the Turken arose out of a cross between a Brush Turkey and an Araucana but this is not possible given that they are two different species with different chromosome numbers. The more plausible explanation is a chromosomal re-arrangement that took place in a Transylvanian Naked Neck-Araucana hybrid which resulted in all three genes being positioned on the same chromosome. I have crossed the Turken with a number of bantam breeds and found the offspring are all fertile. Turken hens are interesting in that they have virtually no wattles or comb. I have found two types of pea combs in the Turken which can be selected for when breeding. One type has a small pea comb as seen in the red coloured hen shown in the left picture and the other has a different form of the pea comb which I call a bulbous comb as seen in the rooster on the right. Hens with the bulbous form of the pea comb have no comb at all but flat red skin where the comb should be. This is difficult to see in the picture of the hen on the top of the page.