Silver Birmans

I am currently putting together information related to Silver Birmans.  In the next couple of months I will be adding more information and pictures so please keep checking back. To me, there is nothing more stunning then a SILVER BIRMAN.  Many times a person will see a Silver Birman and think that it is beautiful but they do not know what makes it beautiful.  You will also hear people and breeders say that the cat has a "sparkling" appearance.  This is true. 

I also breed silver Persians, this is why I talk to Birman breeders about Silver Birmans.  It is easy to understand silver once you work with it.  I love to talk about the "I" gene with other breeders.  The silver Birmans that are being shown today came from Chinchilla Silver Persians and one line used a high grade silver tabby cat.  You will hear people refer to low grade and high grade silvers.  The less pigment (hair color - blue, seal, blue tabby, etc) on the hair shaft, the higher grade silver it is.  High - low grade silver refers to the amount of hair that is silver or not silver.  The high grade silver has more silver, the low grade has less silver. 

The Inhibitor gene (silver) "inhibits" color on the hair shaft.  People say that Chinchilla Silver or a Shaded Silver Persians look to be sparking.  The hair shaft is inhibited of color except for the tip.  So, on a Birman you will have the point color (seal, blue, seal tabby, etc) only on the tips of the hair and when you part the hair it is white (that the Inhibitor gene working making the hair shaft void of color) and the cat looks stunning because even at a distance you can see that white underneath showing through making the cat look sparkling.  A chinchilla is the same as a shaded silver, the difference is the amount of tipping on the end of the hair.  Chinchilla cats look almost white with very little tipping.  One 1/8 of the hair is tipped in color the rest is silver.  Shaded Silver - 1/3 of the hair is tipped in color, the rest is silver. Silver (the Inhibitor gene) is a dominant gene and can not be carried, think of silver just like you think of tabby.  You can get tabby kittens from one tabby (both parents do not have to be tabby) and if you breed to solids together you are not going to get tabby kittens.  Silver works the same way.  You can get silver kittens by breeding with one silver, some of the kittens will be silver and some will not.  You will not have silver popping up down the road.

There is perhaps confusion of the term carrying silver due to the fact that people think their cat is carrying silver because they can not see it, where it may in fact be a low grade silver.  Frequently low-grade silvers need to be bred from to positively identify their offspring. Another issue that has been brought up is tarnishing. 

Tarnishing can occur in any silver, tarnished cats are pets.  A silver has a pure white/silver hair shaft with only the point color on the tips.  That is what makes it silver.  Tarnishing is when the hair that is supposed to be white underneath has some yellow (tarnish) on it.  Tarnishing can be seen very soon after birth, it will only get more evident as the cat ages.  You will not have a silver that all of a sudden gets tarnishing at a certain age.  You just would not use a tarnished silver in a breeding program.  Tarnishing does not happen that often, and if you breed a silver to a silver it is unlikely you will get a tarnished kitten.  I have also heard people say that if you breed a Silver to a non silver that most of the kittens will be "tarnished", this is simply nottrue.  This is how we got silver Birmans in the first place and how we are still getting them today.  If you breed a high grade silver Birman to a high grade silver Birman you are not going to ever see tarnishing. 

Let me compare it to breeding a Silver Persian (chinchilla or shaded silver) to a solid Persian - this is done all the time.  Every kitten in that litter is probably not going to have tarnish (remember I said tarnishing does not happen all the time, it does not happen that often) they are all going to be solids or silvers.  If there would be a tarnished silver in that litter, this kitten would be a pet quality kitten.

--Christine

About the Silver Inhibitor and Agouti Gene.

Genes are responsible for the features of what your cat will inherit: colour, coat texture, temperament. Eye colour etc. They come in pairs and the letters representing them are as below.

 

Dominant Genes are: A = Agouti, B = Black , C = Full colour, D = Density of Pigment, L = Shorthair, O = Red, S = White Spotting Gene, W = full white colour and I = Inhibitor

 

Recessive Genes are: a = Non Agouti, b = brown, c = Himalayan pattern, d = Dilute, l = Longhair, o = non red, s = no white spotting, and w = non white.

 

Alleles = are different mutations of the same gene

 

Homozygous = the cat has the same two identical genes, BB = Seal/black

 

Heterozygous = the cat has two dissimilar genes, Bb = Seal/black carrying chocolate

 

Phenotype = The external look of the cat.

 

Genotype = The internal look of the cat, or what the cat may inherit and carry on through the offspring. A seal silver tabby carrying chocolate and blue = Aa Bb cc Dd ll II oo Ss

 

Dominant = Show the effect of the phenotype in the cat, one dominant gene must be present to see this, Bb = Black/Seal carrying brown/chocolate

Recessive = When the effect of the phenotype can not be seen in the cat. When only one gene is present, this same gene must be there twice to show the effect of the phenotype, bb = brown/chocolate.

 

The "I" (Inhibitor) and "A" (Agouti) are dominant in all colours. The recessive genes can be carried through numerous generations.

Both "A" and "I" are single and dominant. (what you see is what you get) 

Keeping in mind that colour is separate from pattern.

 

All cats have an agouti pattern "A", visible or not. The "A" brings the bands to the fore, and the yellow, fawn, brown under lying colour. It is the most natural occuring gene going back to nature.

The "A" Agouti gene shows cats in patterns, as Tipped (Abyssinian), Classic (blotched, bulls eye patterns), and Mackerel, (fine tiger bands) and even spots. Introducing a solid colour to agouti can create solids and agouti. Agouti to agouti can also create solids and agouti.

Introducing the Inhibitor gene "I" with the "A" gene will turn the yellow underlaying colour to white/silver, and the shafts of the hair upwards white/silver, hence the banding comes to the fore giving you the silver tabby. The "I" gene with the cat that is not agouti "A" will be a Smoke.

The inhibitor gene, "I", simply 'inhibits' the production of colour on the hair shaft. As a result part of the lower end of the shaft is devoid of colour and appears white or 'silver'.

How you will see the silver is determined by the polygenic activity. Polygenes control the depth of tipping on the hair, varying from 1/4" to 1/2" down the hair shaft, the length of the hair and density.

Due to selective breeding the polygenes can be governed and the results will be foreseen. Polygenes therefore determine how dense the colour appears to the human eye. The more silver, the less tipping of colour present in the hair shaft, the lighter the remaining colour will seem.

 Continually breeding silvers to silvers and keeping the gene pool closed in, an already small gene pool, can be considered undesirable and would not help to improve the type. It is imperative to introduce solids with silvers, to prevent inbreeding, and to improve type. 

 

Tarnishing is incomplete clearing of the yellow pigment of the hair shaft. Resulting in a dirty or tarnished silver which is a fault in a silver cat. Shading can occur in all the colours of the Birmans for many different reasons and is completetly different from tarnishing.

Some silver kittens born, with more tipping (pigment) on the hair, can be mistaken for solid colours, even though they are "low grade silvers". Unless they are used for the silver breeding programme, they should be sold as pets. As a result of silver to silver matings and non silver to silver, in our breeding programme, we have silver and non silver from both.

To be a breeder of silvers you have to be clear in your decisions and have no doubts of what the colours are, and registering them as such. To be able to accept advice from other breeders that have/have had silver breeding programmes, and to have a open mind. To focus on the high grade silver, and the type as per the standard, is a very exciting and different challenge.

The dual registration for the silver breeding programmes, ie: Blue Silver Tabby = 52 s/FA, Blue Tabby pt = 52 FA(s) is recommended to prevent any argument for breeders not wanting silver in their lines in the future.

In my opinion nothing could be more beautiful than a Silver Birman that sparkles inside and out.

 

Sandy Steward, Noelene Dally, Pauline van der Hoorn.

Fancypawz Birmans

Seal Silver Tabby kitten at 8 weeks. Silver will be the most noticable in the tail but that can take some time. This kitten above has the tell tail sign. A traditional Seal Tabby will have a "brownish" tinge on the hairs on top of the nose, silver will not have this, they will have a whitish or greyish tinge on the hairs on top of the nose.

High grade Seal Smoke kitten at 3 weeks. The nose leather is black but the hair on top of the nose is whitish. Also, all silvers (either silver tabby or smoke) will have white hair coming from the ear area, where a solid solid color will have that color hair coming out of the ear.