Posts Tagged ‘矮鶏’

Ohiki – “Little Chickens”; Possible Hypochondroplasia in Fowl – by David Rogers

December 1, 2009

Above: This fully grown Ohiki rooster easily fits in just one hand. His feet at the ends of his very short legs may be seen barely beneath his wing. Photo courtesy of Toni-Marie Astin of bantamlongtails.com.

I have chosen the Ohiki 尾曳 as the topic for this month’s article. The Ohiki is a true bantam; it has no large-fowl counter part as may be found in other breeds. It’s an interesting little breed that originated in Japan; specifically the Kochi Prefecture, the same region from which the Onagadori originated.

The two breeds seem to have a close kinship. They share the trait of narrow, ribbon-like feathers and quick feather growth. Some Ohiki have even been known to exhibit the non-molting trait to some degree.

Where the Ohiki differs from the Onagadori is that it has a dominant dwarfism trait that causes it to have a normal sized head, a stocky body, and small limbs – especially the legs, which are set quite far forward on the body. This is a dominant, autosomal trait. As such, the offspring only need to inherit the trait from one parent and, since the gene is not on a sex-link chromosome, either sex of progeny may express it.

This very well describes hypochondroplasia; a form of dwarfism that, unlike achondroplasia – a slightly more distorted dwarfism, results in disproportionate physical features. Since I am not a geneticist, I will refrain from claiming that is precisely what it has; I will only say that the dwarfism in the Ohiki appears to be identical to what is known as hypochondroplasia.

At first glance, it would seem that the little fowl have the same body type as the Chabo 矮鶏, Japanese Bantams. Upon closer inspection and review of breeding results, it becomes apparent that the two have different body types.

The Chabo produces long-legged fowl and short-legged fowl in each hatch. Many have a proportionately shaped body. The Chabo’s short legs are caused by a lethal gene. Offspring may obtain one short leg gene and one long leg gene from the parents. Offspring with such a genetic combination have nearly a 50/50 chance of having short or long legs. However, were an offspring to acquire two copies of the short leg gene, one from each parent, that combination is lethal and the chick dies in the shell on or about the 18th day of incubation. Many Chabo breeders breed a long-legged rooster to a short legged hen. This results in better fertility and fewer in-shell deaths resulting from the lethal genetic combination.

The Ohiki differs from this in that the short leg/dwarfism trait is dominant, they breed true to form, and produce no lethal genetic deaths. Unlike the Chabo, each Ohiki parent may be short legged with no lethal consequences to the offspring.

While they do breed true to form, like nearly any genetic trait, there are variations. Of the two lines from which the Ohiki in the US descend, the Wolfgang Vits line had slightly longer bodies, while the Knut Roeder line had shorter bodies. This demonstrates the diversity that can exist even within the same genetic trait.

In times gone by the Ohiki was known as the “Minohiki-Chabo” 蓑曳矮鶏. It was thought that it was a relative of both the Chabo and the Minohiki 蓑曳, a long-tailed, saddle dragging breed with a game fowl type carriage and head. It was however found to be a relative of neither breed. Instead, it is most closely related to the Onagadori 尾長鶏, Totenko 東天紅, and Shokoku 小国.

The rare little fowl were imported into the US in 2002 by Toni-Marie Astin of bantamlongtails.com. Marc King, of longtail-fowl.com, took it upon himself to gather the stock from various areas of Europe and import them into Switzerland where he prepared the export of hatching eggs for over three years.

Since that time Toni-Marie Astin has been breeding the fowl at her facility, Onagadori South Feather Farm, in Georgia, USA. Mrs. Astin has been making careful selections to improve resistance to pathogens found in the US that differ from those it encountered and was mostly immune to in its previous homeland.

The breed seems to have a threshold with the degree of environmental changes that it will tolerate. At this time, severely cold weather and corn (maize) based feed appears to be where the physiology of the fowl draws the line with adaptations.

It certainly is not a breed for everyone, but for those who don’t mind sheltering it a bit, it makes a wonderful and unusual breed to care for.

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