Breeding Policy for Cornish Rex (33)
This document is seen as a way of ensuring breeders observe what is considered 'best practice' in their involvement with Cornish Rex and particularly in their Cornish Rex breeding programmes.
Cornish Rex, unlike most breeds, owe their origin to one cat - Kallibunker. Inbreeding was carried out in the early generations in order to produce the three generations of Rex to rex breeding needed to obtain breed recognition. This practice of inbreeding has continued. Some Cornish Rex do have Devon Rex ancestry due to the initial breedings that took place between Kirlee (the original Devon Rex) and Kallibunker's female descendants when it was assumed Kirlee resulted from the same mutation as Kallibunker. Two blood types have been confirmed in Cornish Rex - type A and type B. Type A is dominant over type B. This means that a cat with type B blood is homozygous for B. type A cats can either be homozygous for A or heterozygous (carrying the B gene). Cats with type B blood have strong antibodies against type A red blood cells. These anti-A antibodies can cause two serious problems : Neonatal Isoerythrolysis (Fading kitten syndrome) and transfusion reactions.
Aims
It is vital regular selective outcrossing be introduced and maintained to increase the gene pool and maintain stamina and health. This is 'best for the breed' in its ongoing development.
Guidelines
Breeders and owners of Cornish Rex and Cornish Rex Variants are recommended to blood type test all their cats but more especially all breeding stock. Blood type A kittens resulting from a mating between a type A stud and a type B queen may die within the first few days of life if allowed to suckle their mother's clostrum. It is also important to know that cats with the relatively rare type B blood can die if given a transfusion of the common type A blood.
All cats used for outcrossing should be thoroughly researched, of sound temperament and free from any hereditary defects.
Breeders should ensure, to the best of their knowledge, any Cornish Rex or Cornish Rex Variants from which they breed are of sound temperament, free from any hereditary defects, (including those listed in the GCCF Standard of Points), and conform as closely as possible to the Standard of Points (excluding the coat description where variants are concerned).
Cornish Rex are not compatible with Devon Rex. Such matings are therefore highly undesirable. The product of such matings will be registered on the Reference Register and cannot be considered to be variants. They cannot be used in either Rex breeding programme and should be placed on the non-active register. It is considered to be in the best interest of the Cornish Rex breed to keep it entirely separate from other incompatible Rex mutations.
Under no circumstances should any cat with Sphynx ancestry be introduced into the Cornish Rex breed. Selection for hairlessness contradicts the coat quality requirements for Rex cats. The product of any matings between Sphynx and Cornish Rex will be registered on the Reference Register. They cannot be considered to be variants nor be used in any Cornish Rex breeding programme and should be placed on the non-active register.
Breeders are recommended not to breed from Cornish Rex or Cornish Rex variants with Long Hair. The long-hair gene has been present in the breed since its accidental introduction in 1959/60. It is considered in the best interest of Cornish Rex coat quality not to perpetuate this factor. Outcrosses made to breeds with Long Hair ancestry should be undertaken with caution. Where possible Breeders are urged to use only cats proven not to be carriers of the long-hair gene.
Breeders shall ensure that any Cornish Rex or Cornish Rex Variants from which they breed, shall be registered with the GCCF in accordance with the Rules in force at the time.
It is recommended that the progeny from any matings that are not required for Cornish Rex breeding, should be placed on the Non-Active Register, to avoid the introduction of the Cornish Rex gene into other varieties of pedigree cats.
The majority of matings are most likely to be between Cornish Rex x Cornish Rex and Cornish Rex x Cornish Rex Variant, but to ensure maximum benefit from outcrossing Cornish Rex Variant x Cornish Rex Variant matings are necessary. Normal coated progeny from Variaot x Variant matings cannot be considered variants as this can only be proven by test matings.
Breeds which have been approved for use in outcrossing are: Abyssinian, Asian Shorthair, British Shorthair, Burmese, Oriental, Russian Blue, Siamese.
All other breeds are listed as non-approved.
Breeders will be encouraged to take advantage of any relevant official scheme, which may be devised by the Cornish Rex & Devon Rex Joint BAC to test the soundness of the Cornish Rex breed.
Note: It is recommended where the colour of a cat is in question a DNA test, (where such a test exists), be arranged.
Cornish Rex, unlike most breeds, owe their origin to one cat - Kallibunker. Inbreeding was carried out in the early generations in order to produce the three generations of Rex to rex breeding needed to obtain breed recognition. This practice of inbreeding has continued. Some Cornish Rex do have Devon Rex ancestry due to the initial breedings that took place between Kirlee (the original Devon Rex) and Kallibunker's female descendants when it was assumed Kirlee resulted from the same mutation as Kallibunker. Two blood types have been confirmed in Cornish Rex - type A and type B. Type A is dominant over type B. This means that a cat with type B blood is homozygous for B. type A cats can either be homozygous for A or heterozygous (carrying the B gene). Cats with type B blood have strong antibodies against type A red blood cells. These anti-A antibodies can cause two serious problems : Neonatal Isoerythrolysis (Fading kitten syndrome) and transfusion reactions.
Aims
It is vital regular selective outcrossing be introduced and maintained to increase the gene pool and maintain stamina and health. This is 'best for the breed' in its ongoing development.
Guidelines
Breeders and owners of Cornish Rex and Cornish Rex Variants are recommended to blood type test all their cats but more especially all breeding stock. Blood type A kittens resulting from a mating between a type A stud and a type B queen may die within the first few days of life if allowed to suckle their mother's clostrum. It is also important to know that cats with the relatively rare type B blood can die if given a transfusion of the common type A blood.
All cats used for outcrossing should be thoroughly researched, of sound temperament and free from any hereditary defects.
Breeders should ensure, to the best of their knowledge, any Cornish Rex or Cornish Rex Variants from which they breed are of sound temperament, free from any hereditary defects, (including those listed in the GCCF Standard of Points), and conform as closely as possible to the Standard of Points (excluding the coat description where variants are concerned).
Cornish Rex are not compatible with Devon Rex. Such matings are therefore highly undesirable. The product of such matings will be registered on the Reference Register and cannot be considered to be variants. They cannot be used in either Rex breeding programme and should be placed on the non-active register. It is considered to be in the best interest of the Cornish Rex breed to keep it entirely separate from other incompatible Rex mutations.
Under no circumstances should any cat with Sphynx ancestry be introduced into the Cornish Rex breed. Selection for hairlessness contradicts the coat quality requirements for Rex cats. The product of any matings between Sphynx and Cornish Rex will be registered on the Reference Register. They cannot be considered to be variants nor be used in any Cornish Rex breeding programme and should be placed on the non-active register.
Breeders are recommended not to breed from Cornish Rex or Cornish Rex variants with Long Hair. The long-hair gene has been present in the breed since its accidental introduction in 1959/60. It is considered in the best interest of Cornish Rex coat quality not to perpetuate this factor. Outcrosses made to breeds with Long Hair ancestry should be undertaken with caution. Where possible Breeders are urged to use only cats proven not to be carriers of the long-hair gene.
Breeders shall ensure that any Cornish Rex or Cornish Rex Variants from which they breed, shall be registered with the GCCF in accordance with the Rules in force at the time.
It is recommended that the progeny from any matings that are not required for Cornish Rex breeding, should be placed on the Non-Active Register, to avoid the introduction of the Cornish Rex gene into other varieties of pedigree cats.
The majority of matings are most likely to be between Cornish Rex x Cornish Rex and Cornish Rex x Cornish Rex Variant, but to ensure maximum benefit from outcrossing Cornish Rex Variant x Cornish Rex Variant matings are necessary. Normal coated progeny from Variaot x Variant matings cannot be considered variants as this can only be proven by test matings.
Breeds which have been approved for use in outcrossing are: Abyssinian, Asian Shorthair, British Shorthair, Burmese, Oriental, Russian Blue, Siamese.
All other breeds are listed as non-approved.
Breeders will be encouraged to take advantage of any relevant official scheme, which may be devised by the Cornish Rex & Devon Rex Joint BAC to test the soundness of the Cornish Rex breed.
Note: It is recommended where the colour of a cat is in question a DNA test, (where such a test exists), be arranged.
Registration Policy for Cornish Rex
Breeds which have been approved for use in outcrossing are: Abyssinian, Asian Shorthair, British Shorthair, Burmese, Ocicat, Oriental SH, Russian Blue, Siamese, Tonkinese. In addition, American Shorthair and European Shorthair are permitted in the pedigrees of imported cats.
All other breeds are listed as non-approved.
Cats on the Full Register
Cornish Rex which have within the preceding three generations only Cornish Rex.
Cats on the Supplementary Register
Cornish Rex which have within the preceding five generations only Cornish Rex, Cornish Rex Variants, Abyssinian, Asian Shorthair, British Shorthair, Burmese, Ocicat, Oriental SH, Russian Blue, Siamese, Tonkinese. In addition, American Shorthair and European Shorthair are permitted in the pedigrees of imported cats.
Cats on the Reference Register
All other breeds are listed as non-approved.
Cats on the Full Register
Cornish Rex which have within the preceding three generations only Cornish Rex.
Cats on the Supplementary Register
Cornish Rex which have within the preceding five generations only Cornish Rex, Cornish Rex Variants, Abyssinian, Asian Shorthair, British Shorthair, Burmese, Ocicat, Oriental SH, Russian Blue, Siamese, Tonkinese. In addition, American Shorthair and European Shorthair are permitted in the pedigrees of imported cats.
Cats on the Reference Register
- Cornish Rex Variants which have within the preceding five generations only Cornish Rex, Cornish Rex Variants, Abyssinian, Asian Shorthair, British Shorthair, Burmese, Ocicat, Oriental SH, Russian Blue, Siamese, Tonkinese. In addition, American Shorthair and European Shorthair are permitted in the pedigrees of imported cats.
- Cornish Rex and Cornish Rex Variants which have within the preceding five generations any non approved breeds, including non pedigree cats, shall be registered on the reference register as normal or Rex Coated of Cornish type.
NB When kittens with one or both parents registered on the Reference Register are, under this Registration Policy, eligible to be registered on the Supplementary Register it is recommended that the person registering these kittens requests such registration and encloses documentary evidence of the five generations required. If this is not done the kittens may be registered on the Reference Register. - Normal coated cats produced from variant x variant matings will have no breed number only colour description and will be over-stamped 'may carry the Cornish Rex gene'.
- All cats resulting from matings between Cornish Rex and any other Rex coated breed will have no breed number, and will be over-stamped
'not recommended for breeding'. Their progeny will remain permanantly on the Reference Register. - Any cats of Cornish Rex appearance, either Rex or normal coated, with Sphynx ancestry will be registered on the reference register and be
over-stamped 'must not be used for Cornish Rex breeding'. No progeny will ever be recognised or registered as Cornish Rex or Cornish Rex Variants. - All cats resulting from matings between Cornish Rex and any Longhaired breed will be overstamped 'carries the longhair gene'. Their progeny will be overstamped 'may carry the longhair gene'