Dilute carrier eye color

ThunderHill said:

Do some black (carrying dilute) Dd rabbits have blue/gray eyes? Or is something else there, like cchd self-chin?

I have 3 NZ litters currently, all with a blue parent (new to our herd) and either a black or broken black parent (no dilute at all), so all the kits are black or broken black and all are dilute carriers. At least a third of the kits have the dilute gray colored eyes (so cute!, but against breed standards). It's been a while since I've seen one pop up, but my herd has had cchd self-chin colored eyes show up in the past, and I don't know if my newly added blue rabbits carry cchd.

So I'm trying to figure out if it's more likely self-chin (and I should work to cull it out), or if breeding blue to black just causes this and culling would be pointless. Would there be any benefit to only selecting the Dd black rabbits with brown eyes as breeders? My intent is to keep a few of these broken kits to breed back to the blues.

Thanks in advance!

View attachment 41095View attachment 41096
View attachment 41097

Click to expand...

Alaska Satin said:

In my experience, black rabbits with blue-gray eyes have always turned out to be self chins. I have had chinchillas with brown eyes, so it can go the other direction, too. But you really shouldn't see any dilution of eye color from <d>, in either its homozygous or heterozygous state, without concurrent dilution of coat color...though I am not inclined to say anything happens or doesn't happen 100% of the time when it comes to genetics.

One interesting thing is that many of my black self-chin bunnies' eyes ended up changing from blue-gray to brown as they grew up. The brown was somewhat paler than a self black's brown eyes, but was definitely brown enough for them to pass as black.

Your new blue doe could carry c(chd) or even be a self chin herself, since in a blue there's usually no difference in eye color to make you suspect anything. She could also carry a himi c(h) or REW c that would unleash a latent c(chd) in your herd.

The only other thing I can think of that might produce blue or marbled eyes in a black is the vienna gene, but that eye color tends to be a brighter blue rather than blue-gray.

Click to expand...

Alaska Satin said:

In my experience, black rabbits with blue-gray eyes have always turned out to be self chins. I have had chinchillas with brown eyes, so it can go the other direction, too. But you really shouldn't see any dilution of eye color from <d>, in either its homozygous or heterozygous state, without concurrent dilution of coat color...though I am not inclined to say anything happens or doesn't happen 100% of the time when it comes to genetics.

One interesting thing is that many of my black self-chin bunnies' eyes ended up changing from blue-gray to brown as they grew up. The brown was somewhat paler than a self black's brown eyes, but was definitely brown enough for them to pass as black.

Your new blue doe could carry c(chd) or even be a self chin herself, since in a blue there's usually no difference in eye color to make you suspect anything. She could also carry a himi c(h) or REW c that would unleash a latent c(chd) in your herd.

The only other thing I can think of that might produce blue or marbled eyes in a black is the vienna gene, but that eye color tends to be a brighter blue rather than blue-gray.

Click to expand...

ThunderHill said:

@Alaska Satin Thanks again for the great reply! Do you happen to know if any of those other possible hidden recessive can cause excessive white hairs in the ears of a broken? I've never had this much white before. This particular doe didn't kindle any with gray eyes, but all three of her broken kits have ears like this to some extent. The sire is a new blue buck.

Click to expand...

Alaska Satin said:

I am not aware of any gene having been identified that causes more or less white on the ears of a broken. I always like to think of the broken allele <En> as if it's a pail of whitewash tossed in the direction of a colored rabbit, one pail for broken <En_> and two pails for Charlie <EnEn>. In that scenario it is a bit random where the whitewash will end up on the rabbit, although it is a rare broken that does not have white feet (I've never seen one). But there are modifiers or unidentified genes or polygenes that control the distribution of white on a broken colored rabbit; broken colored patterns are quite heritable. Blanket or spotted patterns run in family lines, as do unbalanced nose markings, white in the colored parts of the ears, heavy or light markings, and other little features of the color distribution. Unfortunately for breeders of English Spots, Rhinelanders, Checkered Giants and Dwarf Papillons, pattern isn't always passed perfectly from parents to offspring, but many kits' patterns will resemble their parents' more than not. And if the modifiers or unknown genes are not completely linked to the broken colored gene, they could be carried and passed on by a solid <enen> parent.

There is a gene called white ear that in its heterozgous form <WEwe> gives the rabbit entirely white ears, and in its homozygous state <WEWE> produces a white-eared rabbit with additional patches of white on its body that resemble a badly marked dutch pattern. Until recently it was rare or nonexistent in the U.S. It's still found mostly in Holland Lops here, but you can be sure that it'll start popping up all over as it's currently a bit of a fad.

But your bunnies look like pretty typical broken colored bunnies... daily dose of cute, by the way.

Click to expand...