Join Date: Feb 2012
Location: Neither here nor there
• Horses: 0
If the stallion is heterozygous for both they have a 25% chance of passing both tobiano AND Splash, 50% chance of passing one or the other, and 25% chance that the foal will get neither. If they are homozygous for either one then the odds change and the foal has 100% chance of getting a color gene. However to what degree the genes express is impossible to tell. A horse can carry frame or splash and be totally solid, and minimal tobiano may be just some white on the legs. Most heterozygous splashes (without additinal white genes) are just a crooked bottom heavy blaze, some leg white or a blue eye- often not enough to qualify for APHA regular papers.
However on the whole, yes your odds are somewhat better (75% rather than 50%) if the horse carries multiple white genes than a single one, on getting a foal that has a color gene.
Last edited by Tryst; 08-14-2013 at 12:04 PM.