Grullo Horses: Characteristics, Genetics, History & Care | Draw It Out®
Grullo Horses: Characteristics, Genetics, History & Care
By Jon Conklin • Updated • 6–8 min read
Smoky body, black points, a sharp dorsal stripe, and tiger bars on the legs—grullos look like they were carved from weathered steel. Here’s what creates the color, where the type shines, and how to keep them willing through long weeks.
What Is “Grullo/Grulla”?
A grullo (also spelled grulla) is a dun-diluted black horse: slate or mouse-gray body with black points and primitive markings. Unlike true gray horses, grullos do not progressively lighten with age.
“Dun on black: smoke over steel.”
Genetics & Primitive Markings
Base: Black.
Dilution: One copy of the dun gene (D) lightens the body, preserves black points, and adds markings.
Primitive marks: Dorsal stripe, leg barring (“tiger stripes”), shoulder shadow, cobwebbing on forehead, ear tips, frosting on mane/tail.
History & Working Uses
The dun pattern is ancient and practical—camouflage on open country. Today, grullos show up in ranch horse classes, reined cow horse, roping, and all-around western events where mind, feet, and durability matter.
Care & Grooming for the Look
Keep the contrast
Rinse sweat to prevent salt haze on the smoky body. Clean white marks and highlight the black points for sharp outlines.
Skin first, shine follows
Skip harsh detergents that strip oils. Consistent curry + soft brush builds a healthy, even sheen across the slate coat.
Legs show everything. Support the skin barrier on cannons and pasterns, keep them dry, and tackle crud early so work stays comfortable.
Show-Ring & Photo-Day Tips
Deep-clean the night before; morning = targeted touch-ups (elbows, hocks, tailhead).
Short, specific warm-ups to avoid sweat marks before your class or shoot.
Let primitive markings pop: crisp dorsal stripe and leg barring read great on camera.
I will never stop talking about how great and convenient this spray is and is our saving grace. I prefer to use this spray before a workout and when we are hauled out in the trailer, the best to spray after a run.
Jenna, this is exactly why we made the spray. Quick, easy, and there when you need it—before the ride to keep them loose, after the run to keep them fresh, and even on the road when the trailer miles stack up. We’re so glad it’s become your “saving grace.” Thanks for letting us ride along with you and your horses.
