Hickory, a 12-year-old quarter horse mare, had competed in a rodeo in Regina, Sask., on a warm September day. Unfortunately, after Hickory and her rider completed running a pole pattern, the horse suddenly went down. At the event, veterinarians treated the mare with intra-venous (IV) fluids and medication, then referred her to the VMC in Saskatoon for further treatment.
Hickory had shown acute signs of tying-up syndrome — trembling, sweating and a stiff gait. Her symptoms progressed rapidly after competing, and after going down, she was unable to get up.
“We were concerned because she had been down for many hours,” says Dr. Claudia Cruz Villagran, a former faculty member at the WCVM and a specialist in large animal internal medicine. “We calculated that she must have spent 12 hours [lying] down, which is not good for a large animal.”
Tying-up or rhabdomyolysis describes multiple disorders that affect the body’s muscle system, causing muscle-cell destruction and decreased performance.
“This is similar to when a person runs a marathon and it’s hard to move the next day,” explains Cruz Villagran.
The large animal clinical team used the time that Hickory was being transported from Regina to the VMC to prepare a game plan and assign duties to each member. Cruz Villagran and other members of the hospital’s large animal team had previously dealt with cases of tying-up. That background helped everyone be ready to help Hickory as soon as her owner arrived at the hospital.
“If you don’t have the knowledge or experience, this case could have gone badly,” says Cruz Villagran. “Each case is different and you have to evaluate the situation quickly, see which position the horse is in, and go from there.”
The team prepared the hospital’s neurological stall, which has a hoist and padded walls to help keep unsteady or down animals safe. They also set up IV fluids, catheters, shavings for bedding, a mat and other essential items so they didn’t lose any time.
“Once we opened the trailer and saw the horse, we knew our plan was going to work,” says Cruz Villagran. As a first step, the team worked quickly to insert an IV catheter and to anesthetize Hickory so they could safely move her out of the trailer and into the hospital stall. Twenty minutes later, the team used IV fluids and medication to resuscitate the mare.
“While she was still waking up for the anesthesia, she was a very smart horse because she didn’t try and fight us or kick us,” says Cruz Villagran.
Throughout the night, Hickory continued to receive vital IV fluids and was constantly monitored. Aside from the horse being down for many hours, a significant concern for Cruz Villagran was the health of Hickory’s kidneys. Tying-up can cause extensive muscle damage, which leads to the release of a protein called myoglobin into the bloodstream. Myoglobin, which is darkly pigmented, and other muscle proteins must be filtered through the kidneys. If a horse that’s passing dark, red-brown urine isn’t kept hydrated, their kidneys can be damaged.
“It was really bad — the kidney enzymes were the colour of Coca-Cola,” says Cruz Villagran, describing Hickory’s test results.
Hickory’s prognosis wasn’t good after the first night. But by the third day of treatment, Hickory suddenly got up after a couple of attempts in the stall and was able to stay standing with the help of a rehabilitative sling. After three more days of treatment, the mare was discharged.
“Recovery is different in each case. It depends on the horse, their condition and the amount of damage,” says Cruz Villagran. “In Hickory’s case, she was fantastic to work with. She didn’t try to thrash around; she stayed calm and took her time to let us help her.”
Cruz Villagran worked with Hickory to slowly build up her strength, taking her for short walks in the hospital’s indoor breezeway and then graduating to outdoor walks and grazing.
“I sent her [owner] home with a detailed plan for going back into exercise and using a very conservative plan,” says Cruz Villagran.
She followed up with Hickory’s owner about a month after the emergency and was happy to hear that Hickory was doing well. The key takeaway for Cruz Villagran,in this case, was being prepared for the situation.
“The team was great, and we had our Plan A and Plan B, and everyone was on the same page,” she says. “Having those possible scenarios already discussed was a great starting point before the horse even arrived at the VMC.”
The low-down on down horses
Why is a down horse cause for alarm?
When a horse is down for a lengthy period of time, blood flow to muscles and organs slows down because of the immense weight of the horse’s body. The longer a horse is down, the animal’s muscles become more compressed because of the lack of blood flow. This can lead to inflammation in the fascia (envelope covering the muscles), which can cause severe cellular damage in the muscles as well as a disturbances of normal electrolytes and muscle enzymes.
Why does a horse go down?
- Orthopedic problems such as laminitis, a fractured limb or a joint dislocation
- Nerve paralysis, caused by a puncture wound or some type of trauma
- Severe colic can cause a horse to collapse due to dehydration, internal bleeding or pain
- Tying-up (rhabdomyolysis) due to muscle inflammation
- Heat exhaustion or dehydration
- Neurologic conditions such as equine herpesvirus, rabies or West Nile virus
- Cardiac issues such as atrial fibrillation or ventricular tachycardia fibrillation
- A difficult foaling
What should you do?
- Stay calm. Working with a down horse can be very stressful, plus the animal is already agitated and distressed because it can’t get up or out of the situation.
- Be aware of your surroundings and your safety. Do not put yourself in a dangerous situation.
- Before phoning your veterinarian, evaluate the horse’s surroundings so you can provide as much information as possible. Details can help the veterinary team gather up tools such as ropes, a sling and specific medications. The more history you can pro-vide, the better equipped your veterinarian will be to deal with your horse.
- If your horse is trapped (such as in a mud hole, river or trench), your veterinarian may decide to call the local fire department or an animal rescue team (if available).
- If your horse is down because of suspected laminitis or colic, your veterinarian will decide whether your horse needs fluid therapy or a blood transfusion before moving the animal off the property.
- If your veterinarian is in agreement, you may want to try and offer water to the down horse. It may help to determine the horse’s mental attitude.
Click here to view a "down horse' video presentation with Dr. Cruz Villagran.