BLOG: How Splash Genes have been linked to defects in foals
Taking Caution with Splash White Gene Crossings in Horses
The Splash White gene in horses produces popular coat patterns but has recently been associated with a variety of health risks, particularly when multiple Splash White genes are combined in breeding. Breeders and geneticists have observed congenital abnormalities linked to the presence of multiple Splash White alleles in foals, raising concerns about responsible breeding practices.
Documented Issues with Multiple Splash Genes:
In 2024, breeders reported numerous foals with defects stemming from multiple Splash White gene pairings, specifically when both sire and dam carried Splash 1 and Splash 2 alleles. These issues were reported:
- Short Tongues: Over 50 documented cases of foals born with shortened tongues, leading to nursing difficulties in our private survey in 2024.
- Skeletal Abnormalities: 9 Cases of scoliosis and missing ribs were reported, adding complexity to the health concerns.
- Deafness: Already well-documented, deafness remains a common issue in Splash White horses – particularly those with SW2.
Ongoing Research:
Universities are actively studying the genetic mechanisms behind these defects. Preliminary findings suggest that the interaction between multiple Splash White alleles and other genetic factors, such as Dominant White mutations, may play a role. Understanding these interactions is crucial to minimizing health risks in foals.
Implications for Breeding Practices:
To mitigate risks, it was recommended to us by University specialists breeders should:
- Perform Genetic Testing: Identify Splash White status in both sire and dam before pairing.
- Avoid Pairing Multiple Splash Alleles: Limit crossings of Splash 1/Splash 2 on both sides of the pedigree (IE: Sw1 + Sw2 to Sw1 + Sw2) to reduce the likelihood of defects.
- Consult Experts: Work with geneticists and veterinarians to make informed breeding decisions.
The goal is to produce healthy, high-performing foals while preserving the beauty of the Splash White pattern. By staying informed and documenting any abnormalities with those studying the genes, breeders can avoid contributing to these troubling trends and support the long-term welfare of their horses.
Looking Ahead:
As research continues, we anticipate more clarity on how these genetic factors interact. This knowledge will empower breeders to make ethical, informed decisions and maintain the integrity of their breeding programs. We are also sharing this information to save breeders from the negative financial and emotional impact of losing a foal. We are not experts but these are known documented cases from all over the world in data collected on a survey we did last season.
Stay tuned for updates as studies are published, and remember: responsible breeding starts with knowledge. We are not geneticists or veterinarians just sharing knowledge we have learned from our peers in the industry.
For more information on Splash Genes please visit: https://vgl.ucdavis.edu/test/splashed-white