colorpattern

Paint Pattern Breeding

Try as they might, Paint have never been able to 'fix' every paint pattern so that all breedings produce spotted offspring. Unless a homozygous tobiano is involved, there's no guarantee that a paint breeding will result in a spotted foal. This problem is not isolated just to paint, but plagues all 'color breeds' including Appaloosas*, Palominos, Buckskins and Cremellos. *There are homozygous leopard and snowcap Appaloosas.

When you breed a paint with another paint or solid, various outcomes can result depending on the pattern and genetic make-up of each paired individual. Click here to see a comprehensive table which shows the possible results in any paint breeding.

When breeding for overo, it would make sense to the casual observer that to increase the odds of a loudly marked foal, one would breed two loud overos together. Usually, this is true. However, if both overos possess a frame gene, there is also a one-in-four chance of producing a lethal white foal. These unfortunate snow-white babies are either born dead or usually die within 24 hours because of incomplete digestive tracts. Because of the increased probability of a lethal white foal, it's a common practice to breed overos to solids; however, this also increases the chance for a solid foal. The fact is that a frame overo can produce a lethal white foal regardless of what it is bred to--the likelihood is highest when bred to another frame and rare when bred to any other color or pattern.

Breeding To Avoid Lethal White

Research indicates that, when bred together, splash whites have never produced a lethal white and sabinos have produced few--if any--lethal white foals. The outcome of crossing the various patterns together are listed below:*

Safe crosses will not result in lethal white foals. If you want to avoid lethal white, use these crosses in your breeding program. Rare crosses will produce lethal whites on rare occasions (less than 1 in 4). These crosses are relatively safe for avoiding lethal white foals but they will occur from time to time. 1 in 4 crosses will produce lethal whites 25% of the time or one in four breedings, statistically speaking. AVOID these crosses to lower your chances of producing a lethal white foal.

* This table is reliable only when the horses are definately identified in their pattern. A large number of overos have multiple overo genes so it can be difficult to be positive that frame is not present in a supposedly "safe" breeding. Also, sabinos have very rarely produced lethal whites--however, the crosses may have had "invisible" frame genes present.

** If the tovero's overo gene is not frame, the cross is safe or rare; if the overo gene is frame, the cross is rare or 1 in 4

*** Remember that minimum frames are "invisible" so if a lethal white occurs from one of these "safe" crossings, there is a frame gene in the mix somewhere.

Although overos cannot truly be homozygous in the sense that a loud-colored foal will be produced with every breeding, knowledgeable breeders can increase the odds in their favor by doing a little homework. Whether a breeder decides to breed an overo to another overo or instead to a solid, the overo(s) to be used should exhibit as many pinto genes as possible. Once a person understands the characteristics of each pattern, it's a lot easier to see more than one pattern going on in a particular horse. The more spotting genes within each horse's makeup, the higher the odds of a well-spotted foal being produced. It can also be said that in the case of overos, the more white on the horse, the higher the probabilty for a loud foal. Don't forget when doing your match-up homework that if both horses appear to have frame genes in their multi-pinto gene blend, 25% of the foals from these crosses will be lethal white; if only one of the two multi-pinto gene horses appears to have a frame gene, a lethal white will still be produced from time to time. It's a risk you need to be aware of!

When it comes to producing guaranteed tobianos with every breeding, one merely needs to breed a homozygous tobiano to any color or pattern and the foal will be spotted. On a rare occasion, a tobiano produced from a homozygous breeding will be solid with four white legs and a few white hairs in the tail or mane, but it's still a tobiano, and depending on whether or not it is homozygous, this "solid" foal will produce spotted offspring from 50-100% of the time! It's interesting to note that, unlike overos, nearly solid tobianos produce loud-spotted foals nearly as well as tobianos which already have loud patterns. Also, research shows that if you breed tobianos back and forth, each generation will be successively whiter than the last, until you end up with a horse with a white body and a dark head, complete with a blaze!