Another ID thread

http://img.tapatalk.com/d/13/10/29/7a6uge2a.jpg

This is the best I managed to get of him. He's more gray in person. I had to use my iPhone and flash to grab it. He has a blaze on his face and a patch of white on his right side. His fur is also different. He looks fuzzier instead of smooth coated. Any ideas?

http://img.tapatalk.com/d/13/10/29/sygy2y6e.jpg
http://img.tapatalk.com/d/13/10/29/u2umygag.jpg

Ok pulled him out and managed to get more color accurate photos. I apologize for the blur. He won't sit still and I didn't feel like pulling out the DSLR. His whole belly is white and it extends up to make that white patch.

Looks like an agouti rex... But I'm terrible with colors, so take that with a grain of salt :)

I agree looks like an agouti rex, I wonder if it's a berk too? Hmm I'd like to see what satomi says. Regardless nice rat :)

I can't tell color from the picture - but that face marking is considered a Blaze. You need to be careful, however, because the pattern comes with a genetic, fatal disease - MC or Megacolon. I'm not a fancy rat breeder, so I'm not sure how to identify a rat who shows signs of it, but it runs in Blaze, Dalmatian and Variegated - anything high white. I believe that would make him/her a Blazed Berkshire.

:( I should exchange him then. :( awh man. That makes me feel real bad.

High White is a misleading term. SOX10 Dominant White Spotting, the one responsible for Megacolon can look English, Berkshire, etc. That said, there are several genetics associated with safe markings.

One is Variegated, you see Capped, Notched Capped, Variberk, Berkshire, Irish, BEW/REW, Masked Patched, etc. Another is Dalmatian which is also a Variegated line, but the markings are a bit different. They don't look like a traditional Dalmatian (you see better Dalmatians in Variegated H(e) lines, imo. Then you have Recessive Blazing which is also safe. Essex is lethal dominant (also not in the US), but it is not MC associated either. So, really, there is only one marking gene associated with MC (SOX10 Dom). Unfortunately, it's quite common in the pet trade. Markings can mimic that of Variegated, Recessive Blazing, etc. but it also has an exclusive marking associated with it (Split Cap/Stripe and Split Cap).

It's almost impossible to tell which you have, although there can be indicators, unless you breed it out (test breed) or if you have Split Cap/Stripe. It's usually best to stay away from undocumented marking lines though. As Megacolon is quite devastating to have to deal with.

He looks like an Agouti Wedge Blazed Variberk, by the way. Keep in mind, that is only the phenotype as (again) it can be very hard to identify genotype. :)

Looks agouti, maybe Russian blue agouti (hard to tell for sure from the pictures). Blazed Berkshire markings, and looks to have rex fur.

Like Michelle said, there are different genes associated with white markings, and "high white" is a very misleading term. Personally, I hate the term because it gives the idea that anything with "a lot" of white is at risk. That's simply not true. The markings associated with Sox10 genetics are the ones that are at risk for megacolon. These markings can be combined with the safe H-locus markings. These markings can also resemble safe H-locus markings. I think that's where the confusion comes in. But to be clear, rats with a "a lot" of white are not the only ones at risk for megacolon. Rats with very little, or even no white at all, can also carry the genetics for megacolon, or even develop megacolon.

Without knowing the background of the rat in question, you don't have any way of knowing whether or not he has the potentially to carry the megacolon genes and pass them on to his offspring. You can keep him and try breeding him, but you'll want to do some very heavy inbreeding to tease it out, if it is there, and be prepared for the worst just in case.

Thanks guys. I got him from Petco. I've noticed for the past few days I've had him he sneezes a lot, which I think is a sign of respiratory illness. I need his future babies as feeders so I don't want to have to keep breeding only to find out I have to scrap him and his offspring if he does carry MC. As much as I feel like a crappy person I'm going to call Petco today and explain the situation (needing him to breed for feeders excluded). This Saturday I only work one job so my boyfriend and I plan on a trip to the East Bay Vivarium and I'll pick out some rats there.

Thanks for the help! I very much appreciate it.