They're so cute! My Henny is like a mix of both your horses hehe.
Chiila, what is the phenotypic difference in a brown based buckskin and a bay based? Henny is definitely brown based, he's almost black right now :/ He was such a nice golden color but with this winter coat coming in he looks like a completely different horse. Not trying to threadjack, just curious :)
That's your biggest phenotypical aspect: the color change is drastic. That is very characteristic of browns. Bays and buckskins change color too, but they still look like the same horse. Browns have a whole array of different colors.
Bay = A
Brown = At
Wild bay = A+ (I have never actually seen a wild bay, but I have seen a wild buckskin. I squee-d a little..)
The three are all extremely similar because they are very slight variations of the same gene, which is hard to explain to people when they're convinced their uber brown horse is bay (mostly because people don't seem to like having a lame brown horse.. Brown is classy, IMO. :P)
His dam would have At, which is testable through Animal Genetics (UC Davis has the A test and A+ does not currently have a test.)