mag ox

[susan in greece]

What results have you had in feeding it as a calmer? Heavy or light? What IS the difference?

[Azrael]

Didn't do much for mine so guess they weren't deficient in the first place. Mia was grumpier than usual, made no difference to Roxy and bubbles got the squits. Jay sensibly refused to eat it and threw the bucket at me ;D

[lisap]

Here is a copy of a reply sent to me by Zoe Davies, one of the UK's registered equine nutritionists. Whether people agree or not with her, my view would be to make sure that your horse has a deficiency in any vitamin or mineral before supplementing their diet.

Magnesium

Supplementation with magnesium (one to two ounces of magnesium oxide per day) has been suggested as a treatment for nervous horses and to help horses hoof growth. The rationale for this treatment is entirely questionable!

Severe magnesium deficiency--general nervousness, excitability, muscle tremors, and convulsions in horses is extremely rare as dietary intake is usually more than adequate. Nonetheless, it is easy to believe that supplementing horses with magnesium might help to calm horses although all evidence of this is anecdotal.

Magnesium in pasture/forage is usually between 0.1 and 0.2%, but in some areas of the country it's higher. This is more than adequate for most horses and ponies. Fortunately for the horse, the magnesium needs of about 0.1% per day are easily met by a normal diet (the magnesium content of most horse feeds is between 0.1% and 0.3%). Magnesium absorption tends to be in the 40% range, with utilization of added dietary sources, such as magnesium sulphate, sometimes somewhat better (up to about 70%). Recent research suggests the availability of magnesium oxide is questionable anyway!

About 60% of the body’s store of magnesium is tied up in the skeletal structure, 30% in muscle and the rest is used in enzyme activation.

Regarding Mg supplementation for hoof growth/quality, Mg is needed for about 300 enzymes (proteins that help to catalyze chemical reactions). So Mg is used in a minor role in enzymes used to make new hoof but not to build the hoof structure itself! This is allo irrelevant as horses are not Mg deficient anyway!

Neither magnesium deficiencies nor toxicities have been reported in horses being fed normal diets, except in the rare case of lactating mares which have demonstrated tetany (intermittent muscle spasms, similar to those produced by the disease tetanus) as a possible result of a high-potassium, low-magnesium diet and high levels of magnesium being excreted in the milk. The condition is far more common in milking cattle, which do not absorb magnesium as efficiently as horses.

Experimentally induced magnesium deficiencies in foals have produced muscle tremors, nervousness, uncoordinated movement, and eventually, collapse, convulsive paddling, and death. There have been no studies on the effects of high-magnesium diets, probably because historically this has not been a problem, but with the increasing propensity for owners to feed magnesium supplements without knowing the Mg status of the horse or the dietary Mg intake this will probably lead to increased numbers of horses with hypermagnesaemia even though horses apparently have a high tolerance for this mineral.

Mg absorption and excretion follows the same pattern as calcium and feeding high amounts of forage increases Mg absorption from the gut.

NRC 2007 states 500kg horse will need 7.5g Mg today rising to 15g if in very hard work



There is no doubt that feeding additional magnesium supplements should not be undertaken without knowledge of a known deficiency in the overall diet, Pasture is extremely unlikely to be deficient even though there are times of the year when levels may be slightly lower than expected. Spring pasture may cause excitability due to high sugar levels not low magnesium!

How many horse owners can honestly put their hand on their heart and say they know what the base magnesium levels of their horses diet is??? Until proper scientific research is conducted, long-term use of magnesium supplements should be avoided, horses simply don’t need them.

[jill]

My pasture is deficient - I had the soil tested, and I am led to believe that due to over use of nitrogen for many many years that is true of a lot of ground in this country. The statement regarding pasture above sounds authoritative but there is no evidence cited to back it up. Similarly what evidence is there for her statement that very few horse are deficient in magnesium - that is a very sweeping statement?
I am one of those in the "anecdotal evidence" category, and I have to question whether there have ever been any clinical trials which lead to the conclusion that Ms Davies comes to. Probably not, because no-one would be prepared to fund them, so anecdotal evidence is all there is. And for me, in the light of all of that and the fact that Mg is an entirely natural mineral that grazing animals can access to a greater or lesser degree, I can see no harm and possible benefits from giving it a try.
As regards your question about light/heavy, I use light, but I have no particular reason except that's what I have always used. Ask Jackie.

[anastasia55555]

i think its the light that saxon has.
has made a good difference for him!

[Louise C]

I've been feeding Magnesium for the last 2 years for Flynn's feet - I tried it as a calmer and it totally didn't work (along with every other one I've tried!) I did however run out just over a year ago and Flynn went down with a very slight laminitis attack so I carry on feeding it at a teaspoon a day throughout the year. A local farmer said we were deficient in mag round here - he has to supplement his sheep.

[megansmum]

the land round here is mag deficiant too' cows get staggers etc' only feed the minimum of light anyway'