HGG Community Forums

Ammit explained that there are two factors which contribute to darkening a red coat--Sooty and DP. Sooty shows up in the gene test and DP does not. If a horse has no sooty or is heterozygous there and looks like it should be SstySsty, you can feel pretty sure that it is homozygous DP, but the proof would be to breed it to horses that are homozygous DP and see what their foals look like. Horses that are homozygous DP and either homozygous or heterozygous Ssty will be called Liver Chestnuts when gene tested.

I think that DP can be found in Bay-based horses, but I'm not sure how to spot it. Likewise a black-based horse may carry it, but it will only show in offspring which are not homozygous EE.

Here is a link to my horses that have been given my DP tattoo. The one bay in the bunch has it because I'm pretty sure that his sire is homzygous DP.
http://www.huntandjump.com/adv_search.php?status=any&ageg=&agel=&agee=&erag=&eral=&erae=&f_basic=none&f_adv=none&tattoo=sca+dp+carrier&f_limit=25&stallion=1&mare=1&name=&name_lm=like&color=&color_lm=like&bty=1&lined=lined&foundation=1&sire=&dam=&barn=&owner=137592&breeder=&e1=1&e2=1&a1=1&a2=1&f1=1&f2=1&p1=1&p2=1&s1=1&s2=1&s3=1&c1=1&c2=1&c3=1&d1=1&d2=1&g1=1&g2=1&ch1=1&ch2=1&z1=1&z2=1&sa1=1&sa2=1&kit1=1&kit2=1&kit3=1&kit4=1&kit5=1&kit6=1&kit7=1&kit8=1&kit9=1&sp1=1&sp2=1&rb1=1&rb2=1&o1=1&o2=1&l1=1&l2=1&v1=1&v2=1&brindle1=1&brindle2=1&patn1=1&patn2=1&patn3=1&patn4=1&patn5=1&patn6=1&wf1=1&wf2=1&wf3=1&wf4=1&wf5=1&wf6=1&offset=25

Honestly I would just skip breeding to a stallion with such rules. Some people get way to into rules and it just gets silly.

Horses that test as Liver Chestnuts have to have at least 3 pigment density genes, so SstySsty DP, SstyS DPDP, and SsytSty DPDP all count. The first 2 will both be typical liver chestnuts, and chestnuts homozygous for both appear nearly black.