Ulisse Aldrovandi, illustrations of crested hen and cock, from the Ornithologiae tomus alter of 1600
Crested chickens are a group of ornamental chicken breeds characterised by a tuft or crest of upward-pointing feathers on the head.
Crested chickens are a group of ornamental chicken breeds characterised by a tuft or crest of upward-pointing feathers on the head.
A skull excavated in England suggests that crested chickens were present there in Roman times. [1] [2] Early depictions of these birds are found in the Ornithologiae tomus alter of Ulisse Aldrovandi of 1600, and in the work of Dutch animalier painters such as Melchior d'Hondecoeter in the later seventeenth century. After the exhibition poultry breeding developed in Europe and North-America in the nineteenth century, several old crested breeds became widely known. Original crested chickens originate from the Netherlands, France, Italy, Poland, Russia, and in the Western Balkans. Apart from these breeds, crested chicken are found in Africa and Iceland.
The development of the feather crest is based on the mutation "Crest" (Cr). Its inheritance is incomplete autosomal dominant. This means, that homozygous but also heterozygous animals show a crest, which is however more pronounced in homozygotes. [2]
The extreme upright stand of the head feathers of many breeds, like the Polish, can be attributed to a skull malformation, which is known as cerebral hernia or vaulted skull. Neurobiological investigations showed that this malformation alters the brain anatomy without any functional relevance. [3]
A cerebral arteriovenous malformation is an abnormal connection between the arteries and veins in the brain—specifically, an arteriovenous malformation in the cerebrum.
Hydrocephalus is a condition in which an accumulation of cerebrospinal fluid (CSF) occurs within the brain. This typically causes increased pressure inside the skull. Older people may have headaches, double vision, poor balance, urinary incontinence, personality changes, or mental impairment. In babies, it may be seen as a rapid increase in head size. Other symptoms may include vomiting, sleepiness, seizures, and downward pointing of the eyes.
The domestic turkey is a large fowl, one of the two species in the genus Meleagris and the same species as the wild turkey. Although turkey domestication was thought to have occurred in central Mesoamerica at least 2,000 years ago, recent research suggests a possible second domestication event in the area that is now the southwestern United States between 200 BC and AD 500. However, all of the main domestic turkey varieties today descend from the turkey raised in central Mexico that was subsequently imported into Europe by the Spanish in the 16th century.
A molera is a "soft spot" on the top of a Chihuahua's skull; it is the equivalent to the bregmatic or anterior fontanelle in human babies, but unlike most mammals Chihuahua's fontanelle persist into maturity. Historically it has been very common amongst Chihuahuas and was regarded as a mark of purity for this miniature dog breed. It is still mentioned in many Chihuahua breed standards, however, it is considered a fault in European countries because of concern that this might reflect underlying malformations such as hydrocephalus and ventriculomegaly, Chiari-like malformation and syringomyelia. Fontanelles are fibrous, membrane-covered gaps that lie between the skull bones and at the intersection of the cranial sutures. The cranial sutures are the junctions between cranial bones. The fontanelles serve as the major sites of bone expansion during post-natal skull growth which accommodates the enlarging brain. The Chihuahua likely has a molera because of neuroparenchymal disproportion i.e. a proportionally big brain for the skull. This is likely because there is premature closure of the skull base cranial sutures. To accommodate the developing brain there is increased growth of the skull bone in a parallel plane giving the dog a characterised domed or "apple-headed" appearance.
In neuroanatomy, a gyrus is a ridge on the cerebral cortex. It is generally surrounded by one or more sulci. Gyri and sulci create the folded appearance of the brain in humans and other mammals.
The domestic duck or domestic mallard is a subspecies of mallard that has been domesticated by humans and raised for meat, eggs, and down feathers. A few are also kept for show, as pets, or for their ornamental value. Almost all varieties of domesticated ducks, apart from the domestic Muscovy duck, are descended from the mallard.
Intracerebral hemorrhage (ICH), also known as cerebral bleed, intraparenchymal bleed, and hemorrhagic stroke, or haemorrhagic stroke, is a sudden bleeding into the tissues of the brain, into its ventricles, or into both. It is one kind of bleeding within the skull and one kind of stroke. Symptoms can include headache, one-sided weakness, vomiting, seizures, decreased level of consciousness, and neck stiffness. Often, symptoms get worse over time. Fever is also common.
Brain herniation is a potentially deadly side effect of very high pressure within the skull that occurs when a part of the brain is squeezed across structures within the skull. The brain can shift across such structures as the falx cerebri, the tentorium cerebelli, and even through the foramen magnum. Herniation can be caused by a number of factors that cause a mass effect and increase intracranial pressure (ICP): these include traumatic brain injury, intracranial hemorrhage, or brain tumor.
The Wyandotte is an American breed of chicken developed in the 1870s. It was named for the indigenous Wyandot people of North America. The Wyandotte is a dual-purpose breed, kept for its brown eggs and its yellow-skinned meat. It is a popular show bird, and has many color variants. It was originally known as the American Sebright.
Decompressive craniectomy is a neurosurgical procedure in which part of the skull is removed to allow a swelling brain room to expand without being squeezed. It is performed on victims of traumatic brain injury, stroke, Chiari Malformation, and other conditions associated with raised intracranial pressure. Use of the surgery is controversial.
The Crested is a breed of domestic duck. It was probably brought to Europe from the East Indies by Dutch ships. It has its appearance because it is heterozygous for a genetic mutation causing a deformity of the skull.
The Polish or Poland is a European breed of crested chickens known for its remarkable crest of feathers. The oldest accounts of these birds come from The Netherlands; their exact origins are unknown, however. In addition to combs, they are adorned with large crests that nearly cover the entirety of the head. This crest limits their vision, and as a result can affect their temperament. Thus, though normally tame, they may be timid and easily frightened.
The Sebright is a British breed of bantam chicken. It is a true bantam – a miniature bird with no corresponding large version – and is one of the oldest recorded British bantam breeds. It is named after Sir John Saunders Sebright, who created it as an ornamental breed by selective breeding in the early nineteenth century.
The Campine is a breed of domestic chicken originating in the northern part of Belgium. It is named for the Campine region of north-eastern Belgium and south-eastern Netherlands. It was known there as the Kempisch Hoen.
The Brabanter is a Dutch breed of crested chicken originating in the historic region of Brabant which straddles Belgium and the Netherlands. It is an ancient breed and is shown in 17th-century paintings. A bantam Brabanter was created in around 1934.
Neuronal migration disorder (NMD) refers to a heterogenous group of disorders that, it is supposed, share the same etiopathological mechanism: a variable degree of disruption in the migration of neuroblasts during neurogenesis. The neuronal migration disorders are termed cerebral dysgenesis disorders, brain malformations caused by primary alterations during neurogenesis; on the other hand, brain malformations are highly diverse and refer to any insult to the brain during its formation and maturation due to intrinsic or extrinsic causes that ultimately will alter the normal brain anatomy. However, there is some controversy in the terminology because virtually any malformation will involve neuroblast migration, either primarily or secondarily.
The Padovana or Padovana dal gran ciuffo is an ancient Italian breed of small crested and bearded chicken. It originates in, and is named for, the city and surrounding province of Padua, in the Veneto region of north-eastern Italy. Despite continuing discussion surrounding its true origins, it is recognised in Italy as an indigenous Italian breed.
The Polverara, also known as Schiatta (Italian) or S'ciata (Venetian), is an ancient breed of crested chicken from the area of Polverara in the province of Padua, in the Veneto region of north-eastern Italy.
Solid black plumage color refers to a plumage pattern in chickens characterized by a uniform, black color across all feathers. There are chicken breeds where the typical plumage color is black, such as Australorp, Sumatra, White-Faced Black Spanish, Jersey Giant and others. And there are many other breeds having different color varieties, which also have an extended black variety, such as Leghorn, Minorca, Wyandotte, Orpington, Langshan and others.