By Don Blazer
When it comes to “tying-up” in horses, we may have information overload. Too many names, too much information and no “authoritative” solutions!
(I have a “it hasn’t failed me yet” solution; not authoritative, but effective.)
Tying-up is characterized by muscle stiffness, especially in the hindquarters and loin, at times profuse sweating, reddish brown to almost black urine and obvious signs of severe pain.
The malady used to be known as Monday Morning Disease and was incorrectly called “azoturia”. Azoturia originates from azote, the French word for nitrogen, indicating an abnormal amount of nitrogen in the urine. That is usually not the case in horses tying-up, hence it should have a different name. And it does today. Medical research recognizes two basic forms: Polysaccharide Storage Myopathy (PSSM) and Recurrent Exertional Rhabdomyodysis (RER). Both are names for horses exhibiting the signs up tying up, but RER is usually associated with Thoroughbreds, while PSSM is directed at most other breeds. (There is some evidence that the malady is inheritable.)
A University of Minnesota reports suggests RER is caused by an abnormality in intracellular calcium regulation. There is no specific diagnostic test.
PSSM on the other hand is generally thought to be caused by an abnormal accumulation of sugar (glycogen) stored in muscles.
Tying-up occurs when horses are being exercised. It can occur within minutes of the start of exercise or when a horse becomes exhausted or sweats excessively, resulting in the addition of an electrolyte imbalance.
Years ago it was called Monday Morning Disease because work horses suffered the affliction when they went back to work following a weekend of rest.
Those work horses were the performance horses of the time. Today, tying-up occurs on any day and at virtually any time in horses getting consistent amounts of healthy exercise and plenty of feed—in other words, “performance horses”.
To make it simple, we could call it the “performance horse” disease. It is rarely, if ever, seen in horses not being used in some form of performance.
My experience with tying up has always been associated with race horses, both Quarter Horses and Thoroughbreds, primarily in California and Arizona, states in which a lot of alfalfa is fed.
Alfalfa has a lot of drawbacks when it comes to being used as a horse feed, one of which is an over-abundance of calcium. In addition to the calcium from the alfalfa, many high performance horses are given supplements which contain high levels of calcium.
Considering that RER suggests an intracellular calcium regulation problem, it is highly likely the horses I was dealing with were being affected by the feeding program…high amounts of calcium.
According to the veterinarian I was working with at the track, the overdosing of calcium leads to the suppression of the parathyroid gland which regulates the calcium level in the blood. The suppressed parathyroid is unable to replace the large amounts of calcium used by nervous energy and muscle usage, and the muscles suffer tetany (sustained muscle contraction).
As simple as it may seem, controlling the amount of calcium in the diet eliminated tying-up in several cases for me.
The first success was with a mare sent to me from New Mexico. She was in perfect health, but tied-up almost instantly upon entering the race track for morning exercise. Of course she was well fed and she was “excited” about going out to gallop, so her nerves were on edge.
We stopped feeding her alfalfa (she was being fed alfalfa in New Mexico) and provided no supplements. Within two weeks she stopped tying up, and while she didn’t have a stellar racing career, it wasn’t because she tied up.
A trainer across the shed row from me complained constantly about a mare he had that tied-up on a regular basis. He wanted to get rid of her, so I bought her for a very few dollars.
Off all alfalfa and supplements which contained calcium, the mare was ready to run in just under 30 days. She won her first race for me, and we sold her for a lot of dollars the very next day.
A trainer friend was having trouble with an Arabian mare that tied up. I suggested the same remedy…no alfalfa, no calcium supplements.
The mare was back showing within 3 weeks and never tied up after that.
When a horse ties-up the breathing may be hurried, muscle stiffness is evident, and complete lameness of the hindquarters may occur.
The horse will not want to move. Don’t move the horse. Start to help the horse by leaving the horse right where it is. Get a blanket over the horse if possible and get a veterinarian as soon as possible.
If the horse is not in too much distress, walk the horse very slowly to his stall or pen.
It’s pretty standard for veterinarians to treat tying-up with a tranquilizer to relax muscles and then with medication to reduce pain.
Today’s medical research has no cure, but change of diet is almost always recommended, along with light controlled exercise. The problem with the medical recommendations is that none are considered “solutions”…just somewhat preventative.
And the changes in diet are often somewhat complicated, so nothing is really singled out as the factor. Providing a vitamin/mineral supplement, good quality grass hay, free choice salt and plenty of fresh water is the basis for a good feeding program.
If a diet change is recommended, be sure to “consider” limiting the calcium intake.
Sometimes too many names and too much information is too much!