Height Reduction

John, first of all thanks for being here and opening this forum to questions.

I understand that dwarfism is not essentially about height, however - if I breed stallion A to mare B and have offspring smaller than both sire and dam, does that indicate the involvement of a dwarf gene, or is it just random height fluctuation? If you add to the equation the pretty but somewhat domed head and large eyes that we see often in this breed but assume a correct bite and no other dwarf features, does that affect your answer?

Thanks,

Jan

"if I breed stallion A to mare B and have offspring smaller than both sire and dam, does that indicate the involvement of a dwarf gene, or is it just random height fluctuation? If you add to the equation the pretty but somewhat domed head and large eyes that we see often in this breed but assume a correct bite and no other dwarf features, does that affect your answer? "

You are correct, height has a high rate of variability with respect to carriers just as it does with non-carriers. If a foal is born to 2 parents and ends up being smaller than both, I would be curious about that but you would need to look at other offspring of both of those parents, ie does the stallion have a majority of small foals with less influence from the dams. Does the mare always have foals smaller than her, etc. Those questions do not help you rule out the foal being recessive completely, but you could look at it as if the majority of the stallion's foals are small then you would look at the smaller height as normal genetic variance and not due to a recessive dwarf gene the foal has inherited. Same thing for the mare. The head is something that is so variable, I do not rule by it. Exotic head with a pedigree that is known to have dwarfs, that is a concern.

John