BEW Genetic code question

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sometimes( but not always) Vv have white marks, its in relation to dutch marking factors, which may strengthened by v and occur in a lot of BEWs
 
Hi all, I am using everbreed to use in my rabbitry. I am trying to put the genotype in for BEW. Does anyone know the genetic code for a BEW or how I can get everbreed to automatically fill in based on the pedigree info? I am a genetic dummy.. lol
For a BEW you only know the genes are ----------vv
Since those vv genes cover up everything else in a white blanket, you don't know what is under it just by looking at the rabbit.
You mention having a pedigree. Are all the rabbits in the pedigree BEW? If not, you may be able to figure out a couple of the rabbit's genes based on the parents' colours.
If the pedigree is all BEW rabbits, the way to figure them out is by test-breeding to a coloured rabbit (preferably one that has very recessive genes, such as a lilac Himalayan)
 
For a BEW you only know the genes are ----------vv
Since those vv genes cover up everything else in a white blanket, you don't know what is under it just by looking at the rabbit.
You mention having a pedigree. Are all the rabbits in the pedigree BEW? If not, you may be able to figure out a couple of the rabbit's genes based on the parents' colours.
If the pedigree is all BEW rabbits, the way to figure them out is by test-breeding to a coloured rabbit (preferably one that has very recessive genes, such as a lilac Himalayan)
Her sire is BEW, mom is Black tortoiseshell VM
 
Her sire is BEW, mom is Black tortoiseshell VM
So mum is <aaB_C_D_eeVv> The problem is that she only passes down half of her genes, so we now only know for sure that this BEW rabbit is <_a_______evv> as s/he necessarily got an <a> and a <e> from mum.
Do you know the colours of the grandparents, mum's side? with that we may figure out the recessive genes of the mum, and get a bit more of the BEW's genotype figured out
 
Nice! So now we have this info, assuming the pedigree is right.:
gsire: <A_B_C_D_E_Vv>
gdam: <A_B_C_ddeeVv>

However for these two to give out a tort child, both of the grandparents have to have recessive a. That is completely possible, but it still makes me raise an eyebrow about the pedigree (If you are able to get pictures of the gsire, gdam and dam that could help confirm all of that, or better yet a picture of the dam's litter). Unfortunately, this only reveals one extra letter for the dam's genotype:

Dam: <aaB_C_DdeeVv>

And that extra letter doesn't give us anything sure about the BEW, since she may have inherited D or d. If the gsire and gdam on dad's side are anything other than BEW, that may help.

Otherwise, if you are able to get a sire with a good deal of recessive genes to pair her with, you will be able to figure out more. Of course, this is only important if you are trying to figure out which colours you can get out of her. If not, there is not really a need to figure out the entire genotype, other than to potentially make things easier for a future buyer of her kits.
 
Nice! So now we have this info, assuming the pedigree is right.:
gsire: <A_B_C_D_E_Vv>
gdam: <A_B_C_ddeeVv>

However for these two to give out a tort child, both of the grandparents have to have recessive a. That is completely possible, but it still makes me raise an eyebrow about the pedigree (If you are able to get pictures of the gsire, gdam and dam that could help confirm all of that, or better yet a picture of the dam's litter). Unfortunately, this only reveals one extra letter for the dam's genotype:

Dam: <aaB_C_DdeeVv>

And that extra letter doesn't give us anything sure about the BEW, since she may have inherited D or d. If the gsire and gdam on dad's side are anything other than BEW, that may help.

Otherwise, if you are able to get a sire with a good deal of recessive genes to pair her with, you will be able to figure out more. Of course, this is only important if you are trying to figure out which colours you can get out of her. If not, there is not really a need to figure out the entire genotype, other than to potentially make things easier for a future buyer of her kits.
 

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Now we're talking!

I threw some basic calculations around and got this (Feel free to add it to the pedigree in everbreed, may make your life easier in the future):

NOTE: for the dam named "C", the name of the colour does not coincide with the genotype added. She's said to be Choc agouti vienna carrier, but the genotype says she has chd. That would make her a chocolate chinchilla. All the info below assumes the colours written down are right, but I left that chd in there as I assume it came from somewhere


Black knight Black otter <ataB_C_D_E_>
Stormy Black <aaB_C_D_E_>
Eddie Fawn <A_B_C_ddee>
DOS Choc broken <aabbC_D_E_Enen>
Frankie BEW <A_B_______vv>
CoCo Chocolate <aabbC_D_E_>
Chester MLBP42 Fawn VC <A_B_C_ddeeVv>
Annie Fawn VM <A_B_C_ddeeVv>

S Black <aaB_C_D_E_>
C Choc Aug VC ? <Aabbchd_DdEeVv>
Haagen Dazs Chestnut VM <AaBbC_D_E_Vv>
CreamSickle's D Cream VM <AaB_C_ddeeVv>

ER009 BEW <_a_b_____evv> (If C's info is correct, ER009 cannot be <CC>).
(Dam) Black tort VM <aaB_C_DdeeVv>

Fancy BEW <_a_______evv>

So... we have a bunch more information, but that unfortunately has not given us new certainties about Fancy. She is probably a self (aa), and has a good chance of having inherited at least one brown gene (b).
To figure out the rest you will need to test breed, but that doesn't mean the pedigree's info is useless, it will help you solve some mysteries surrounding her kits as you will be able to trace some colours or patterns back to their ancestors.
 
Oh gosh. Thank you so very much. I have got to figure out a way to learn this and comprehend it.
I'm still learning myself, but I found you learn very fast by doing what I just did - seeing colours and trying to "decode" them.

Everbreed's blog happens to have what I consider the simplest of the guides about all this, you can find it here.

There are a lot of exceptions and funky combinations (And Fancy happens to be one of those exceptions), but for most rabbits you can more or less figure out what they have based on what you see once you understand the very basics, and they you can learn the exceptions and the funky combinations at your own pace.
 
Her sire is BEW, mom is Black tortoiseshell VM
You really can't be sure about the genetic code of a BEW or a dominant color like chestnut unless you know one or both parents had a recessive color or pattern phenotype.

A BEW of unknown parentage would be <?? ?? ?? ?? ?? vv>.

Sire BEW <?? ?? ?? ?? ?? vv>
Dam Black tortoiseshell VM <aaB-C-D-eeVv>

So, you know your BEW is <_a ?? ?? ?? _e vv> since she'd necessarily get a self <a> and a non-extension <e> from her tort dam.

What you know about your BEW's grandparents is not super helpful since you don't know which of their alleles they passed to her parent(s), other than whichever parent was the offspring of the cream gdam probably got a dilute and/or non-extension allele. I say "probably" because "cream" is a common name for a color that may differ among countries and breed standards. In the USA it usually (Holland Lops, French Angoras) refers to a dilute non-extension chestnut agouti <A_B_C_ddee>, aka non-extension squirrel, aka non-extension blue agouti.
 
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You really can't be sure about the genetic code of a BEW or a dominant color like chestnut unless you know one or both parents had a recessive color or pattern phenotype.

A BEW of unknown parentage would be <?? ?? ?? ?? ?? vv>.

Sire BEW <?? ?? ?? ?? ?? vv>
Dam Black tortoiseshell VM <aaB-C-D-eeVv>

So, you know your BEW is <a_ ?? ?? ?? e_ vv> since she'd necessarily get a self <a> and a non-extension <e> from her tort dam.

What you know about your BEW's grandparents is not super helpful since you don't know which of their alleles they passed to her parent(s), other than whichever parent was the offspring of the cream gdam probably got a dilute and/or non-extension allele. I say "probably" because "cream" is a common name for a color that may differ among countries and breed standards. In the USA it usually (Holland Lops, French Angoras) refers to a dilute non-extension chestnut agouti <A_B_C_ddee>.
Oh, ok. Thank you
 

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