I bred two pedigreed American Chinchillas that both looked grey. I have attached a picture of one. Their kits started of grey but are all turning brown by the minute. Is there something wrong? They are 3 weeks old now and it's hard to get a good picture of them since they are bouncing everwhere. But they are brown not at all like their parents
No, there's nothing wrong with those adorable bunnies (at least in their color).
It's not uncommon for chinchilla kits to be "rusty" for a while; many of my chinchilla Satins and chinchilla Mini Rex looked like that. Sometimes they were so rusty that I mistook them for coppers for a brief period (yours aren't that bad). I learned that the places to look to determine the color were the lower face/cheeks and the flanks, and especially the nape triangle (it would be tan in a chestnut/copper/castor, and silver in a chinchilla). The rusty chinchillas usually were just rusty across the top of their shoulders/backs and sometimes their forehead area. None of them ever had a tan nape triangle.
Nape triangle:
The thing about the chinchilla allele is the it suppresses
most or all pheomelanin (the yellow pigment that makes tan/orange/red tones). It seems to be a time-dependent thing, being less effective at that suppression at first... every rusty chinchilla kit I ever raised ended up molting out into a normal chinchilla coat.
It would be genetically unlikely (impossible, as far as we know) for two chinchilla rabbits to make chestnuts, which is an agouti with tan coloration in the places you find white on a chinchilla (particularly the bands on each hair). Chinchilla comes from an allele, <
c(chl)> that is recessive to the full-color allele <
C> that allows chestnut rabbits to develop the tan/orange tones in their fur. Each rabbit has two alleles, with one generally being dominant over the other (unless they're the same), meaning that the dominant one is expressed and the more recessive one "hides."
Here is the dominance hierarchy of the alleles (different forms of a particular gene) on the C locus (the spot on the genome that contains two of the various alleles that determine certain colors or patterns). It is a hierarchy, which means that no allele can hide any allele that is dominant to it (above it on the list).
Known alleles at the C locus
<
C> - full color
<
c(chd)> - chinchilla, suppresses most or all pheomelanin (yellow pigment that makes tan/orange)
<
c(chl)>- sable/shaded, suppresses all pheomelanin and changes the expression of eumelanin, turning tan into white, and black into sepia; temperature-sensitive
<
c(ch)> - removes all pigment from most or all of the head and body (which becomes white) and eyes (which become pink), and allows color development on the cooler extremities (nose, ears, feet and tail); also temperature-sensitive (so sometimes there's "smut" or dark patches on head/body where it gets chilled
<
c> - REW suppresses all pigment everywhere in fur and eyes.
So, a chinchilla colored rabbit could not "carry" (hide) a full-color <C> and then give it to their kits. The alleles that could hide behind a chinchilla allele are sable <
c(chl)> a, himalayan <
c(h)> or REW <
c>. It wold take two of these to create something other than a chinchilla kit, which means that both parents would have to carry one or the other of them; that would be unusual in an AmChin for several reasons (though REW would not necessarily be
too surprising).
Once in a while you'll see a sable chinchilla (aka sable agouti), which is a rabbit that is sable-based <
c(chl)_> instead of chinchilla-based <
c(chd)>, being shown as a chinchilla. This happens more in breeds that have other varieties, rather than only the chinchilla variety like AmChins. But it would be surprising to find it in purebred AmChins. In the case of sable chinchillas, it's the dark markings that are brownish - sepia, actually - not the paler parts, as you see in your bunnies. (Your bunnies still have bright black ticking, while it's the parts of the hairs that are supposed to be white that are brownish).
