I depends whos genes are dominant. If they were both homozygous for their colour then that whould be an interesting mix. But i'd probably say tobanio. Not really experienced in colour though.
Is your mare roan or appaloosa, because you can get an appaloosa cross that is roan but no spotty genes!
You CAN NOT get a homozygous roan, it is impossible! Because homozygous roan is lethal but because of this if both parents put in the roan gene there is no conception, so it not like other lethal genes where they carry the pregnancy through and you loose the foal because of the lethal gene.
If you mare is spotty and the stallion is tobiano you have got a chance of breeding a appiano (appaloosa/tobiano cross) because of the co dominance of the appaloosa gene and tobiano gene.
If your mare is roan, then you have a chance of breeding a roan and white.
To work out your chances of getting which colours I need to know if you mare is spotty and if the stallion is hetro or homozygous tobiano!
thanx, u got me thinkin now, her mare is reg, snowflake app, but wen vet done passport 5 years ago she put strawberry roan, ugh, ok, shes rose and pink with strawberry spots, work that out, shes got tons of feathers . odd perhaps vetalso thinks she got shire in her as she is big boned , bla bla , and the stallion is just tri , shire x tb