Hier even een stukje waarom geen knoflook. (artikel is van Dr. Karen Hayes een zeer vooraanstaand paardenarts in USA)
Why Not?
Garlic contains a chemical compound called N-propyl disulfide (also known as “allicin”). It’s also present in domestic and wild onions, and in chives. And, it’s toxic for certain animals, particularly horses, cattle, and dogs. It damages their red blood cells, causing the cells to develop little pimples called Heinz bodies. This triggers the spleen to snatch the damaged cells out of the circulation and gobble them up—it’s one of the spleen’s jobs. The result is a declining red blood cell count, leading to a specific type of anemia called Heinz body anemia. The toxicity of allicin has been known for decades. It’s written up in veterinary toxicology text books dating back to the 1960s, as well as in newer texts published within the last couple of years. And, it’s been confirmed in a Canadian study published in the March 2005 issue of The American Journal of Veterinary Research: Just four ounces of dried garlic mixed with molasses and given twice a day for about a month caused significant anemia that caused dramatic signs of illness. Five weeks after the garlic was removed from the diet, blood tests showed the horses still harbored high numbers of damaged cells sporting those telltale Heinz bodies.
Sounds cut-and-dried, right? It seems that there should be no controversy about this—if garlic contains a toxin that can harm horses, then there should be nobody willing to jeopardize his horse’s health by feeding him garlic, right? But it’s not that simple.
Why The Controversy?
If your horse sustained a deep cut on his leg that was bleeding profusely, he’d quickly lose a lot of blood, and it’d be obvious by looking at him that he was in serious trouble—he’d become weak, confused, and shocky. But the blood loss from Heinz body anemia is slower and sneakier than that, and it allows his body to adapt to the declining red blood cell count. As a result, unless you look closely, and know what you’re looking for, you’re unlikely to see any sign of trouble—he looks fine and acts fine. Of course, as the anemia progresses, his pink gums will get progressively paler, his stamina will progressively decline, and he’ll become progressively more lethargic. But, as a prey animal, he’s hard-wired to conceal the fact that he doesn’t feel well. By the time his condition is clearly visible from the outside, it’s safe to say he’s lost a lot of blood —possibly more than half his total blood volume—while exerting every ounce of his strength to project an image of health, for survival’s sake. That’s one of the things that makes Heinz body anemia so dangerous: It’s sneaky. I’ve seen mild cases that required a blood test to make the diagnosis, and the only treatment required was to stop giving the garlic, minimize stress, and give the horses a couple months to recover and build up their red cell counts. And, I’ve seen cases so severe that the horses needed blood transfusions.
Will Horses Really Eat Garlic?
Some will, right off the bat. Many horses will turn their noses up at any feed containing garlic, but will reconsider if it’s laced with molasses. And many horses actually develop a taste for the stuff, even pulling it right out of the ground, fresh and pungent.
How Much Garlic Will Endanger My Horse?
That’s a great question. And unfortunately the answer is pretty unsatisfying: We still don’t know. We don’t know how much, if any, garlic is safe for horses. We don’t know whether fresh garlic is more or less toxic than powdered or freeze-dried garlic. It’d be logical to guess that fresh garlic, which can be about 80 percent water, is less toxic, but sometimes Mother Nature isn’t logical. We also don’t know whether a big dose of garlic, taken one time, is more or less toxic than small doses taken repeatedly. And, we don’t know whether some individual horses, or certain breeds, are more vulnerable to garlic’s toxic effects than others are.
Why Take The Chance?
Until the research is done, why put your horse at risk? Because of the volume of evidence confirming garlic’s toxicity, horse care professionals should be very careful about recommending it for horses until—if—the research is done to show how and in what form it can be safely given. Ultimately it’s up to the individual horse owner to decide what to give his horse. But in order to decide wisely, that horse owner needs to know about the dark side of garlic.
Many people have argued that their horses have eaten garlic for years and are “still standing.” We don’t know how much they’re getting, in what form, and how regularly, and we have no way of knowing whether the horses’ blood is being adversely affected unless a blood test is done. And, knowing what we know about garlic, even the loosest definition of good horse care shouldn’t justify using any supplement “because he hasn’t dropped dead yet!” Our horses deserve better from us.
Play It Safe
Remember, onions and chives can grow wild in pastures. And, a single garlic bulb pulled from a garden and dropped anywhere can take root and become an entire patch of the stuff. Check your fields regularly. Check the fencing around your garden regularly. Make sure your neighbor isn’t giving your horses anything from his garden. Check the labels on all feeds and supplements before you buy. And, when in doubt, ask your veterinarian to run a simple blood test for Heinz body anemia.
Warboel
