Castor/Chestnut Agouti Question

[judymac]

Two questions:
1) I know that quite a while back, the colors 'Wild Gray' and Castor were merged into one color, since they have the same A-B-C-D-E- genetic code. The colors look very different on the rabbits, though. I have mostly Wild Gray, the kits are born black (with white inside the ears), and by the time their eyes open the banding has started on the hairshaft. They do get the chestnut outer color, but very little of the orange/fawn shade in the middle band--the fiber looks mostly gray. It isn't opal, the kits are born black.

I remember from decades past a very bright (wide band maybe) chestnut agouti, that started out light, and grew in the darker bands--almost opposite the wild gray pattern. Does anyone else have castors that start out light instead of black, and grow in the darker bands as they mature? What color are your castor/chestnut agouti kits when they are born, and how do they change color as they mature?

2) On another castor question, I remember from decades ago my mentor stating that agouti should be bred to agouti, but never said why. Do the 'Aa' kits with a self recessive have agouti markings that aren't as clear, or poorer banding? What about kits with the marten or otter tan a(t) recessive? Does it make a difference in the coat? On a different gene, I heard one person say their best show blues were 'Cc', with an albino REW recessive, as it made the blue lighter and clearer. Does a REW recessive on the 'C' color gene actually make a difference? I know that having chinchilla c(chd) as a recessive can mess with the eye color, does having sable c(chl) or pointed white/Californian/Himalayan c(h) as a recessive actually make a difference? What has your experience been?

The old idea was to keep each line as close to homozygous as possible, self to self (blacks could be bred to chocolate to improve the chocolate's color depth, and black to blue to improve the color depth of the blue), agouti to agouti (but not chestnut to orange/fawn), chinchilla kept separate, himi to himi because breeding to REW might wash out the color. But is this accurate? Does it bear out in the real world?

 

[Alaska Satin]

Two questions:
1) I know that quite a while back, the colors 'Wild Gray' and Castor were merged into one color, since they have the same A-B-C-D-E- genetic code. The colors look very different on the rabbits, though. I have mostly Wild Gray, the kits are born black (with white inside the ears), and by the time their eyes open the banding has started on the hairshaft. They do get the chestnut outer color, but very little of the orange/fawn shade in the middle band--the fiber looks mostly gray. It isn't opal, the kits are born black.

I remember from decades past a very bright (wide band maybe) chestnut agouti, that started out light, and grew in the darker bands--almost opposite the wild gray pattern. Does anyone else have castors that start out light instead of black, and grow in the darker bands as they mature? What color are your castor/chestnut agouti kits when they are born, and how do they change color as they mature?

My copper Satins have always been somewhat-to-very bright, but that could be partly due to the structure of Satin fur, and/or related to the wideband that floats around my coppers due to the reds I interbreed with them. My castor mini rex were less bright but still pretty heavily rufus-influenced (also interbred with reds).
Here are representative examples:

I did have what seemed to be two different types of castor mini rex: one had a lot more red tones and was brighter, the other was sort of dull and more grayish. (I preferred the bright ones, so I didn't keep, and thus don't have any photos of, the grayer ones.) Looking back, I wonder if the brighter ones had more rufus factors and/or a copy of the wideband gene. (As I've mentioned before, I'm finding that Satins with a single copy of <w> are subtly different from those with <WW>.) In fact I had one buck I just loved, but that occasionally got faulted on the judging table for his redder surface color. Interestingly, he only had a single red on his pedigree, three generations back; the rest were castors. This is him as a junior (he did darken a bit more as a senior):

However, I can't remember ever seeing a copper or castor that was born looking light instead of dark. I don't seem to have (or can't find) any photos showing their color development, but to my memory they developed like you said - slate undercolor and early chestnut outer color showed up within a week or two. The middle orange band took a lot longer to show up. In both breeds, that would usually appear somewhere around 4-6 weeks, first on the lower flanks, then working its way up and around the body from there.

2) On another castor question, I remember from decades ago my mentor stating that agouti should be bred to agouti, but never said why. Do the 'Aa' kits with a self recessive have agouti markings that aren't as clear, or poorer banding? What about kits with the marten or otter tan a(t) recessive? Does it make a difference in the coat? On a different gene, I heard one person say their best show blues were 'Cc', with an albino REW recessive, as it made the blue lighter and clearer. Does a REW recessive on the 'C' color gene actually make a difference? I know that having chinchilla c(chd) as a recessive can mess with the eye color, does having sable c(chl) or pointed white/Californian/Himalayan c(h) as a recessive actually make a difference? What has your experience been?

I have only encountered two issues interbreeding the various A-series genes. The first is the self chinchilla problem, making selfs with off-colored eyes (sometimes). The other is a tan-to-self cross <at a> that sometimes makes "tweeners," i.e. rabbits that look like selfs until you flip them over and see a hint of otter color on their belly and around their mouth. I've only seen that in one matrilineal line of my Satins, though; it hasn't come up in the other lines.

I've not crossed agouti x otter; I only started with otters a few years ago. But as far as agouti x self <Aa> goes, I've never noticed any effects on marking or banding. All of the Mini Rex pictured were <Aa>, and all were Grand Champions. The booted copper Satin doe seen above, "Boots," was sired by a broken self squirrel buck, so she was also <Aa>.

My beautiful chinchilla Satin that you've seen before, Silverado, was out of Boots and a self chocolate buck.

On a different gene, I heard one person say their best show blues were 'Cc', with an albino REW recessive, as it made the blue lighter and clearer. Does a REW recessive on the 'C' color gene actually make a difference? I know that having chinchilla c(chd) as a recessive can mess with the eye color, does having sable c(chl) or pointed white/Californian/Himalayan c(h) as a recessive actually make a difference? What has your experience been?

I also know Silverado was <cchd c> since Boots was <C cchd> (verified by test breeding) and the chocolate sire was <Cc>. Silverado had fantastic color and markings.

I regularly breed REW x himi. At this point, most of my himis are <ch c> and I have had no trouble with washed-out markings. I have rarely had <chch> rabbits, though, so maybe they'd be better? My current himi problem is marten markings due to crossing a black himi carrier with an otter who's either <C ch> or <C c>.

Having sable as a recessive to chin does make a mess (unless you want sable chins). I experimented with sable in my Satins in the early 2020s. Sable Satins were beautiful (though not an accepted variety), and the process was fun and very educational, but that <cchl> is so sneaky I ended up getting rid of the sable carriers entirely. I have not found similar effects from himi, though; it seems to coexist nicely with my other colors (except the above-mentioned otter pattern!).

As far as blues being lighter and clearer with <Cc> I can't really say I've seen that either. Blue Satins are supposed to be a very deep, not light, blue. My blues are quite deep, and they run the gamut from <CC> to <Ccchd> to <Cch> to <Cc> (but no cchl!).

Allowing for the differences in lighting, all the blues below have extremely dark and deep-running color.

G. CH. Gem is <CC>


G. CH. Kokomo is <Cch>



G. CH. Honey B is either <C ch> or <C c>. He has great blue color and fabulous tan factor.

G. CH. Despereaux Blue is <cchd c> (shown very successfully as a blue but actually a self squirrel)

The old idea was to keep each line as close to homozygous as possible, self to self (blacks could be bred to chocolate to improve the chocolate's color depth, and black to blue to improve the color depth of the blue), agouti to agouti (but not chestnut to orange/fawn), chinchilla kept separate, himi to himi because breeding to REW might wash out the color. But is this accurate? Does it bear out in the real world?

This appeals to me, and old-time practices can hold a lot of wisdom, but I can't say I've followed it at all.

I've worked longest with blues and blacks, and I can say that over time my blacks seem to lose density, while my blues do not, so I routinely cross blues back into my blacks for that reason. I've not really noticed that it affects the color quality, though. It seems to be more that keeping/breeding the individuals with the deepest color (in either variety) produces offspring with deep color.

We are struggling with coarser texture in our agoutis and whites up here, so I am crossing my blacks into the agouti lines and seeing some real improvement in texture and no apparent loss in color quality.

I would prefer to keep the chin separate, because of the constant cropping up of unshowable colors - self chins with blue-gray eyes, blue martens, ermines, etc. But since type and fur are more important than color in Satins (45/30/15 points respectively) and Mini Rex (45/35/15), I deal with it.

Same with reds - I would much, much prefer to breed reds to reds exclusively, as that really does seem to produce the best color. But there is not enough decent stock up here to do that yet, so I'm using coppers and chocolates for the time being.

Looking forward to seeing what other folks have to say, since I only have significant experience with a few breeds.

 

[judymac]

My blues are quite deep, and they run the gamut from <CC> to <Ccchd> to <Cch> to <Cc> (but no cchl!).

Many thanks for your fabulous answer. Your blues are amazing. I did start forty years ago with blues of that color depth, the fiber spun up was darker than that of most blacks. Sadly, I became enamored with some very, very pale dilutes, and quickly destroyed that color depth, never to regain it.

that <cchl> is so sneaky I ended up getting rid of the sable carriers entirely.

How was sable sneaky? What did it do?

I routinely cross blues back into my blacks for that reason. I've not really noticed that it affects the color quality, though. It seems to be more that keeping/breeding the individuals with the deepest color (in either variety) produces offspring with deep color.

Fascinating.

Thank you so much for taking the time to give such clear answers to each question, and great photos to illustrate. I've found that much of the rabbit "facts" that have been reported aren't necessarily true in all circumstances. Just because two things happen at the same time does not make one thing the cause of the other, even though we perceive it that way. I regularly bred my blues with my blacks with no loss of color, until I bought those pale dilutes. Yes, it was blue to black with paler black (and blue) offspring, but the cause was not the dilute 'dd' gene, it was the color depth modifier polygene at fault. It took years to weed out those genetics, and I never again got back to the kind of depth of color on your blues as your photos so beautifully show.