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This is Alouette, a female Jack Russell who is of the leggier type. What's her genotype?
First, she is clearly saddled tan. Genetically, black and tan is all the same, including everything from saddled tan to tan point. There is an unknown modifier that determines just how much tan a dog will have. It is highly unlikely that she would carry recessive black, so this makes Alouette atat saddled tan.
The red seen on Alouette is rather intense, which means she is most likely CC intense red.
She is also piebald. Though for the most part she appears Irish white, she does have white crossing her topline, which is a common indicator in determining whether a dog is piebald or Irish white. Though she may be carrying extreme white, I don't find it likely since she does have so much color. I also find it unlikely that she has a copy of the Irish white gene as the gene is rarely if ever seen in the breed. This would make her spsp piebald.
So, that's atat CC spsp or piebald black and tan.