> ## Content Index > Fetch the complete content index at: https://equinecolors.com/llms.txt > Use this file to discover other available public pages before exploring further. # Bay dun - URL: https://equinecolors.com/bay-dun/ - Published: 2025-11-24T14:02:13.000Z - Updated: 2026-07-31T20:07:31.000Z - Description: Bay dun (also called classis or zebra dun) is a horse color caused by the dun dilution on a bay base. The coat is diluted, and primitive markings are present. - Author: Hannelore Roodhooft - Tags: Colors, Dilutions, #Import 2026-08-12 09:42 ## Appearance | Foals | ![Bay dun foal](https://equinecolors.com/content/images/2025/11/baydunfoal.png) | Bay dun foals have a **golden brown**coat color and [**primitive markings**](https://equinecolors.com/dictionary/#:~:text=a%20bay%20horse.-,Primitive%20markings,-Primitive%20markings%20may). Leg primitives may be harder to see.Foals that also have grey often have intense primitive markings. | | ----- | ------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Dun on a **[bay](https://equinecolors.com/bay/) base** dilutes the coat to a tan or**light golden** color. It also causes **primitive**markings. Points and primitive markings areblack. [**Frosting**](https://equinecolors.com/dictionary/#:~:text=into%20their%20surroundings.-,Frosting,-White%20or%20pale) may be present. | ![Bay dun](https://equinecolors.com/content/images/2025/11/baydun-1.png) | Adults | | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------ | ------ | ### Bay shade variations | Seal browndun | ![Seal brown dun](https://equinecolors.com/content/images/2026/01/sealdun.png) | | ------------- | ------------------------------------------------------------------------------ | | ![Sooty bay dun](https://equinecolors.com/content/images/2026/01/sootydun.png) | Sootybay dun | | ------------------------------------------------------------------------------ | ------------ | ### Mimics Some shades of bay dun can look similar to [buckskin](https://equinecolors.com/buckskin/). Light shade nd1 bay can look similar to [bay dun](https://equinecolors.com/bay-dun/). ![CTA Image](https://equinecolors.com/content/images/2025/12/Equinecolors_Icon_MagnifyingGlass-9.png) Dun causes primitive markings, which aren't present on buckskins.Bay dun horses tend to have a more peachy tone, buckskins are more yellow.The dun dorsal stripe goes through the tail, while nd1 dorsal stripes don’t.Dun is more likely to cause striping at the back of the ears than nd1.Foals with dun tend to have a darker lower face mask, while nd1 foals have a darker forehead. ## Genetics Bay dun is the result of a **bay base** diluted by **one of two copies of dun**. The dun (D) dilution is an allele of the [**TBX3**](https://equinecolors.com/tbx3-gene/) gene. ![CTA Image](https://equinecolors.com/content/images/2025/12/Equinecolors_Icon_DNA1-28.png) Bay dun:Bay (E/\_ A/\_) + D/\_ Dun is dominant, so horses could carry nd1 or nd2 (located on the same gene) without it being noticeable, but still pass it on. D/nd1 horses possibly tend to be lighter than D/nd2 horses. Para valorar [camisetas de fútbol](https://www.camisetatienda.com/?ref=equinecolors.com) con criterios claros, es recomendable revisar las medidas indicadas y el tipo de ajuste. Las fotografías y la ficha del producto deberían confirmar el precio total, el plazo de entrega y las condiciones de devolución. **Read more:** [Bay](https://equinecolors.com/bay/) | [Chestnut dun](https://equinecolors.com/chestnut-dun/) | [Black dun](https://equinecolors.com/black-dun/) | [Dunskin](https://equinecolors.com/dunskin/) [Back to Dun](https://equinecolors.com/dun/) ## Articles 1. An, T.; Dugarjaviin, M.; Han, H. ***Expression and Analysis of TBX3 Gene in the Skin from Three Locations on Dun Mongolian Bider Horse***; Genes (2024); dOI: [0.3390/genes15121589](https://doi.org/10.3390/genes15121589?urlappend=%3Futm%5Fsource%3Dresearchgate.net%26utm%5Fmedium%3Darticle&ref=equinecolors.com) 2. Cieslak J, Brooks SA, Wodas L, Mantaj W, Borowska A, Sliwowska JH, Ziarniak K, Mackowski M.; ***Genetic Background of the Polish Primitive Horse (Konik) Coat Color Variation-New Insight into Dun Dilution Phenotypic Effect***; Journal of Heredity Hered. (2021); Doi: [10.1093/jhered/esab034](https://academic.oup.com/jhered/article/112/5/436/6357767?login=false&ref=equinecolors.com) 3. Imsland, F., McGowan, K., Rubin, C. J., Henegar, C., Sundstrom, E., Berglund, J., Schwochow, D., Gustafson, U., Imsland, P., Lindblad-Toh, K., Lindgren, G., Mikko, S., Millon, L., Wade, C., Schubert, M., Orlando, L., Penedo, M. C., Barsh, G. S., & Andersson, L.; **Regulatory mutations in TBX3 disrupt asymmetric hair pigmentation that underlies Dun camouflage color in horses**; Nature Genetics (2015)*;* Doi: [10.1038/ng.3475](https://doi.org/10.1038/ng.3475?ref=equinecolors.com) 4. Masuda M. Tsunoda J., Nomura H., Kimura N., Altangerel G., Namkhai B., Dolj U., Yokohama Y.***; New Primitive Marking (Bider) in Mongolian Native Horse and Equus przewalskii;*** Journal of Equine Science (2007); Doi: [10.1294/jes.18.145](https://doi.org/10.1294/jes.18.145?ref=equinecolors.com) --- [![CTA Image](https://equinecolors.com/content/images/2025/10/Image-5.png)](https://www.horsereality.com/?ref=equinecolors.com) Learn while playing! Discover how genes shape colors and patterns in our realistic horse breeding game, Horse Reality [Play now ](https://www.horsereality.com/?ref=equinecolors.com)