RE: [RC] flax seed - Susan E. Garlinghouse, D.V.M.
I've been doing some reading on flax seed (ground) and
everyone seems to have a different opinion. One vet's site said only to feed it
once or twice a week soaked with a mash or beet pulp because too much can be
toxic. Another site said a tablespoon a day, another said 1/2 cup per day,
below Mike feeds a cup a day. How do the rest of you on ridecamp feed this and
why?
TIA
Kari
I love researching this kind of thing, it
never ceases to amaze me how a tiny nugget of truth gets blown up over the
years into a big deal. So here’s the deal with toxicity in flax
seed---yes, there are some cyanogenic glycoside compounds in flax seed. When
broken down in the digestive tract by glycosidase enzymes, one of the
by-products is cyanide. In a large enough dose, it can cause some
problems. However, there has never been a single case study of it being an
issue in horses, because horses don’t have enough of the enzyme in
question necessary to create enough cyanide to be a problem. Ruminants,
like cows and sheep, do make a lot of the enzyme---HORSES DON’T.
Even in ruminants, there’s only been a single case study of it making
cattle sick---that was when a bunch of feedlot cattle were inadvertently fed a
tremendous amount of linseed cake (flax after the oil has been removed). It
just isn’t a big deal in horses.
Nevertheless, the cyanogenic compounds can
be driven off by cooking the flax seed and that in part is where the old
practice of boiling the stuff came from. In addition, the seed coat is
pretty hard and as everyone already knows, a lot of the seeds will pass through
intact if the seed is not disrupted by grinding, cooking or at least soaking.
So cooking the seed is fine to drive off
cyanogenic compounds and soften the seed coat, but it also renders the omega-3
fatty acids inactive, thus negating the benefits of the whole project.
Soaking it to soften the seed coat and making “jelly” is fine, but
the omega-3s are also sensitive to exposure to oxygen, so letting it sit too
long (say, more than overnight) before feeding also diminishes the benefits.
Still, a good convenient method if you’re already soaking up beet pulp or
whatever and still retains most of the benefits.
Grinding it fresh before each feeding is
still the gold standard, but inconvenient, especially if you have to run a
power cord, or are feeding a lot of horses or whatever. You can always
grind up big baggies of the stuff and store it in the freezer.
Easiest of all is to just feed it whole
right out of the bag. Yes, you’ll waste a lot and the birds in your
neighborhood will go nuts. It’s better to still mix it with
something wet because the seeds are small and light and easily aspirated
(sucked into the lungs) by accident. You’ll have to feed more, but
you will still get some good benefits from it, just not as much as when you
somehow freshly process the seed.
As to amount, every horse is different as
to his tolerance. It’s a pretty powerful cathartic, so you can’t
feed it willy-nilly without creating some cowsplats or even outright projectile
diarrhea (humans and other critters, too). Start out slowly with maybe a
small handful once or twice a day (yes, it can be fed daily) and work up from
there. If your horse has a need for it and doesn’t get soft poop,
then I’m perfectly fine with them getting more than a pound or two a day.
I’ve fed at that level myself and been more than satisfied. Other
horses can’t tolerate that much and so shouldn’t get that much,
just whatever they can tolerate. It’s not rocket science. J
