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Is magnesium deficiency a common problem?

Yes, magnesium deficiency in horses occurs quite often. Dr. Kees Kalis of the Dutch Equine Health Service has worked on this subject for many years. He says: ‘I have investigated a few hundred blood samples of the Health Service, already measured on the magnesium content.

The blood came from horses with many different illnesses. The results were shocking. 55% of the sick horses had a magnesium value under the norm. Blood samples taken from healthy horses showed only 22%-23% under the norm. A big difference, leading to the following two conclusions: Firstly, sick horses often have a too low magnesium value and secondly, over 20% of healthy horses also have a magnesium deficiency’.

The research

What about the magnesium in roughage? Vincent Hinnen, a nutritionist in The Netherlands, participated recently in research into roughage for horses. In total, roughage of 109 stable yards was investigated. Also in this case, the results gave us a shock.

46% of the samples taken showed a magnesium value under the minimum norm. To complete the research, random blood samples were taken from the horses at these stables. In total 130 blood samples were taken at 26 stable yards. 13% of the horses had a too low magnesium value and 26% just reached the minimum norm. That means that 39% of those horses were in the magnesium danger zone.

What does this all mean for the diet of your horse?

Read the answer in Part 4: About magnesium in roughage and hard feed

Click here for Part 1: Magnesium, a matter of life or death

Click here for Part 2: Bone: A lot of calcium, a little bit of magnesium