Castor mini rex colour question.

[kwilds]

I have a litter of 2 week old mini rex. 3 of them are castor. 2 have a very light coloured belly and the 3rd has a darker grey belly. The dad has the darker grey belly too but most of the pictures/descriptions of castor mini rex show the light coloured belly. Is the grey belly acceptable for showing or would it get disqualified? What gene is it that affects the belly colour? The doe is a black otter and of course has a very distinct white belly. I thought that the A gene was completely dominant over the at but would the at gene cause the castors to have a whiter belly?

 

[Nancy McClelland]

Pictures might help.

 

[SNM]

Pictures really would help,but I don't have my Standards book with me to check for the belly and undercolor.
From what I can tell you bred an Otter to a Castor that's a no no and you will get unshowable or weird looking otters.

I bred a red to a broken otter once. There was nothing but otters and broken otters in the litters. As they got older they didn't have the rusty orange undercolor , they had a red on so all of them were unshowable

 

[pamnock]

The harli gene can mess up agouti belly color.

 

[kwilds]

Yes I did breed an otter to a castor but only because I had bred this doe to an unproven buck 3 times with no babies. She was a proven doe and this castor was the only other buck I had and I wanted to make sure it was the buck that was sterile before I got rid of him. She had a big litter with the first breeding to the castor buck but interestingly the buck that I thought might be sterile ended up having a litter with a different doe that I bred to him just after I bred the castor to the otter! So neither are sterile but that is a whole different issue!!

I have a very large market for pet stock and very little interest in show or breeding stock so the unshowable colours that crop up are not an issue for me. I love some of the colours that can't be shown anyway. I got what I think was a cinnamon in one litter recently but it was a peanut and died before I could really tell.

I will try to get some pictures as soon as it stops raining here!

 

[kwilds]

Why would a castor/otter cross produce weird looking or unshowable otters? The only way an otter would be produced in that cross would be if the castor parent threw a recessive at or a gene right? I did get one otter in this litter and so far he/she looks perfectly normal for an otter.

 

[SNM]

Agouti is dominant over Tan I do believe, but I wouldn't cross them. It will sometimes create ring/band patterns that are questionable and incorrect under color and belly color. Correct me if I'm wrong, this is just what I've seen from these crosses

All those from my Agoutiww x Tan cross all have DQ's, but that could also be from the wideband gene and the rufus factor

You don't breed for show so I wouldn't even worry about it

 

[GorbyJobRabbits]

kwilds wrote:

Why would a castor/otter cross produce weird looking or unshowable otters? The only way an otter would be produced in that cross would be if the castor parent threw a recessive at or a gene right? I did get one otter in this litter and so far he/she looks perfectly normal for an otter.

theres some pretty strict guidlines of what to breed to what to get showable colors. Agutis should stay with agutis. Shadeds with shadeds... exc..

Black is a pretty universal color though.

 

[kwilds]

I realize that certain colour crosses are better for producing showable colours. What I am interested in is the genetics behind those reasons! I do not show at the moment as there are no shows anywhere close enough for me to go to. I do have a healthy market for pets. My main interest is figuring out how the genetics work.