A conversation with Dr. Nathan Canaday, DVM, Horse Division Manager, Four Sixes Ranch
The 2026 breeding season is nearing its end at the Four Sixes Ranch, though calling it a season does not quite capture it as the work flows year round. This stretch is both demanding and rewarding in equal measure. The fruit of that labor is visible everywhere: foals on the ground, happy clients with their dream crosses, and horses from previous crops making names for themselves on the ranch and in the arena.
Dr. Nathan Canaday has been at the Four Sixes Ranch for nearly twenty years now. As the Horse Division Manager, he oversees one of the most respected stallion programs in the country. The Four Sixes stands more than 30 stallions across two facilities, has earned the AQHA Best Remuda Award, and is recognized as an AQHA All-Time Leading Breeder of Performance Horses. We sat down with Dr. Canaday to talk about what it actually takes to manage these horses at the highest level.
The Four Sixes Standard
The Four Sixes is known for setting a high standard in every category, from the cowboys to the horses to the beef. The studs are no exception.
The Four Sixes began offering stallions to the public in 1993, nearly a decade after Dr. Glenn Blodgett arrived at the ranch in 1982 with a charge from Miss Anne Marion to establish a commercial breeding program. What started as an internal goal became one of the most recognized breeding operations in the country.
When you look at the Four Sixes studs, there is no room for mediocrity. So what makes a stallion fit for an elite program like this? Dr. Canaday says it really comes down to one question.
"The short answer is would I want to breed one of my mares to the stud? If the answer is yes, then I'll consider it."
That is where it starts, because at the end of the day, every stallion on the Four Sixes roster has to be exceptional enough for the ranch's own mares. As part of any standing agreement, the ranch retains the right to breed five of their own mares to each stallion every year. That keeps the standard elite and honest.
From there comes a deep dive into conformation, pedigree, genetic testing, and what the horse has actually proven in the arena. No one-hit wonders. Versatility is the north star. Can that horse produce one of the world's best ranch horses when bred to a Four Sixes brood mare? That is the question that matters most.
Horses for the Cowboys. Horses for the Public. Fillies for the Future.
Breeding decisions at the Four Sixes are never made with a single goal in mind. Horses for the cowboys, horses for the public, replacement fillies for the broodmare program. Every cross is a methodical decision layered with intention.
"My number one goal is to raise ranch horses for the cowboys. They have to be very athletic because they have to be able to cut a cow, but yet they have to be big enough to go all day and have enough motor, but yet not too hot. That way they are still gentle and good for selling to the public at the Return to Remuda sale."
On any given mare, Dr. Canaday might be breeding specifically to sell, specifically to keep, or specifically to aim a cross at the cutting or roping markets.
The timeline is what makes it humbling. From the moment a breeding decision is made to the first time that horse is under saddle and working is the sum of years. The full picture takes time and patience built into every decision.
"Sometimes you do not know that you made a phenomenal cross until five years from now," Dr. Canaday said.
What Breeding Season Actually Demands
From February first to July first, there is no slowing down. Studs are collected every other day during the core of breeding season. Most people do not see all the behind the scenes work or the demands on a stallion throughout.
Preparation starts in January, when the stallions are cleaned out and prepped before the season begins. Stallions store semen in the epididymis and vas deferens, and after months without collection, dead sperm cells accumulate. That has to be cleared before the first collection of the year.
From there, the volume ramps up steadily through spring. By the time the Texas heat arrives, these horses are working through fatigue, heat, and sustained physical demand all at once. "You can tell they are tired by the end of breeding season."
And breeding season is not the only demand on them. During one recent stretch, ten different Four Sixes stallions were on the road at the same time, competing at the PCCHA Derby in Las Vegas, the NRCHA Derby, and the NRHA Western Derby in Scottsdale. Stallions that are still actively showing during breeding season require a network of veterinarians across the country who can collect them for fresh semen when needed. When that is not feasible, the team switches to frozen semen to keep mare coverage consistent. "It is a logistical feat. You have to have a whole network of vets that you know and can call up and say, hey, will you be able to collect a stud for us if we need fresh semen?"
Between breeding season demands and their careers in the arena and on the ranch, it is demanding on every aspect of their body. "A lot of them have had a real intense show career, so sometimes they have some low-grade arthritis. We all get old and achy. So we do a lot of things to help with that. We keep them on the Four Sixes joint supplement.”
The gut piece carries equal weight. "We keep them on the Complete Gut Protection because of the stress related to the intensity of breeding season. It is really tough on them."
Stallion Pro Tip: Fit Not Fat
Big, beefy, and overfed. It is a look some people associate with a stallion, but it’s anything but optimal when it comes to health and longevity.
"You do not want fat, you want fit. For metabolic reasons and all the things."
The stallion managers at both locations are intentional about exercise on non-breeding days and consistent turnout. At the Four Sixes Granbury facility, an in-ground underwater treadmill is part of the program. During breeding season, stallions swim two days a week to stay conditioned without overloading their systems. "If we did more than that during breeding season, I think they would just be exhausted and it would start to affect the breeding day and them wanting to collect."
When breeding season wraps in July, the horses get two months to recover. But as soon as temperatures begin to drop in September, frozen semen collection resumes for many of the stallions. How long that lasts depends on the horse and how much frozen semen is needed, anywhere from one month to three. "Some of the studs are going ten months out of the year." Every program is customized to the individual horse because there is still a unique individual variation to it, even between stallions.
Two Locations, One Standard
The Four Sixes now operates stallion programs at two facilities, and the story behind the Granbury location is one of those things that just feels like it was meant to be.
Back in the 1980s, Miss Anne Burnett Marion purchased the Silverado complex south of Weatherford on land that was zoned to Granbury at the time. Her intent was to open a performance horse stallion station there and call it Four Sixes Granbury. For reasons lost to time, that plan never came to fruition and the property was eventually sold. The land that became Bosque Ranch, home to the legendary Buster Welch cutting arena, was built on that same ground.
Decades later, Taylor Sheridan purchased Bosque Ranch. Then he fell in love with the Four Sixes and bought it as well with the intent to preserve the beauty and tradition of the ranch. Somewhere in that process, the connection surfaced: the land he already owned in Granbury had once belonged to Miss Anne, who had envisioned a Four Sixes stallion station there all along.
What she intended in the 1980s finally came full circle. The new Stallion Station at Granbury sits on that same historic ground, carries the name she originally planned for it, and honors the vision she had for it generations before it became reality.
Today, Granbury serves as an intentionally exclusive showcase location. All reproductive work, palpating, breeding, and pregnancy checks happen exclusively at Guthrie. For mare owners whose stallion is at Granbury, the ranch runs a courier between locations at no charge. That commitment to the customer experience runs through everything. One phone number covers both locations:806-386-1911. Semen orders and breeding contracts can also be placed through the Four Sixes website regardless of location.
How He Got Here
Dr. Canaday grew up homeschooled, riding horses and working cattle, with a father who managed a pickle factory and no family land to ranch on. A retired Coors chemist turned junior college science teacher lit something up in him with a biochemistry class that had four students and felt more like a private tutorial. That put him in position to get into vet school at Colorado State, where he was randomly assigned to Dr. Hurd, the equine science director, who happened to be friends with Dr. Blodgett at the Four Sixes. An internship at the ranch followed in 2006.
"Doing that internship here made me realize that you could marry veterinary medicine and the cowboy way of life together in an environment like this," he said. "If I could be a vet at a place like this, that would be my dream job."
Twenty years later, he is living that dream, laced with sweat and a lot of hard work.
Faith. Integrity. Strength. Excellence.
A program built on those principles does not cut corners. It shows up in the cowboys, the cattle, the horses, and the studs. It runs through everything the Four Sixes does, and it is the same foundation behind every formula in the 6666 Equine Supplements line.
Learn more about the Four Sixes studs and place semen orders at 6666stallions.com or call 806-386-1911. Both locations welcome visitors.
Excited about this year's Remuda Sale lineup? The sale takes place September 26th at the Four Sixes Ranch in Guthrie. Follow along with 6666 Ranch for updates on this year's horses.
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Listen to the full conversation below!
At Four Sixes Equine Supplements we focus on the whole horse. The science. What works and stands the test of time, not chasing trends or quick fixes.
Formulated by veterinarians. Trusted on the ranch and in the arena. Built for horses that work.
-The 6666 Equine Supplements Team
