Magnesuim deficiency - make sure your cows are O.k

marion · Post by **marion** » Fri Mar 07, 2008 3:33 am

What is it about conditions in England, that make for such a problem with magnesium, that we don't seem to hear about in Canada? My cows are on average hay in winter, and old pasture from spring to fall. I put out free choice minerals and they don't touch it in the winter but are occasionally interested in it during the pasture season. Grain in small amounts, is just a mixed chop of corn (maize), barley and oats, occasionally wheat with a bit of molasses. Nine years for me with Dexters..marion

Rutherford · Post by **Rutherford** » Fri Mar 07, 2008 12:32 pm

When I visited, I was struck with the vast difference in pasture, and the resulting hay on your side of the pond. Your soils may not be deficient, anyway, but our big problem comes with the fast growing leafy grass, particularly in a wet season. When I send a picture of my animals overseas it is usually followed by comments on the green pastures. One of the penalties of this is probably the greater incidence of magnesium deficiency.
Beryl (Woodmagic)

wagra dexters · Post by **wagra dexters** » Sat Mar 08, 2008 5:00 am

"Grass tetany has been the main cause of deaths in adult beef cows on farms in south eastern Australia over the past 40 years" according to a very good DPI information notes site, titled 'Grass Tetany (Hypomagnesemia) in Beef Cattle', belonging to DSE Victoria Australia. Many other good sites also.

We have never had it either, in twice that time, but we take precautions and touch wood before saying so, Murphy's Law being as it is.
Margaret.

Issy · Post by **Issy** » Wed Mar 19, 2008 12:10 pm

We have been unable to get the mag rolls any closer than 3 hours drive away but have been advised that most farmers in the area use magnesium Chloride flakes in the water. I have been told that they won't hurt the sheep/lambs but would be gratefull if anyone could tell me how much to put in the trough (if there is a problem with galvonised troughs I do have some large plastic containers I could use instead and empty the trough).

Colin · Post by **Colin** » Wed Mar 19, 2008 8:04 pm

Hi Isabel, I use the magnesium chloride flakes in galvanised troughs without any problems.

In terms of how much to use, that's not so easy. I asked at my merchants and they said one handful per day is what farmers do. Well I reckon that'll depend on the size of your herd and the size of your hand ! So I've guessed it and for 12 adult sized dexters I add approx 1 handful 3 times a week (I have quite big hands). I also have a salt lick available to them. I've done this now for a year and all are fine and healthy.

Hope that helps.

Colin

Saffy · Post by **Saffy** » Wed Mar 19, 2008 11:16 pm

Hi Colin,

Do you mean by using the flakes without any problems that you've you been advised that the magnesium won't be altered by the galvanised trough and will therefore still be available in a usable form for the cattle?

I ask because I was advised by my vet that Rumag Aqua, which I think may be a similar thing, reacted with the galv, making it unusable by the cows.

Stephanie

Colin · Post by **Colin** » Thu Mar 20, 2008 12:38 am

To be honest I've not spoken to the vet about it. I was advised to use it at my agricultural merchants and by another previous local dexter breeder. What I use is produced from the Dead Sea, so it looks like sea salt to me. I'm in contact with the vet over a forthcoming TB test so I can ask if they have an opinion.

Colin

Issy · Post by **Issy** » Thu Mar 20, 2008 11:40 am

Thanks for the replies. I only have two dexters plus calves so will ask the vet when I take the dog in later ( I want to check that it won't hurt the lambs before I use it). Will ask about the trough too. Ours is the same make as yours Colin so hopefully will be ok.

Issy · Post by **Issy** » Thu Mar 20, 2008 7:41 pm

Vet said that the dose is 40g per cow per day (don't count calves or sheep) It shouldn't harm anything else. She hadn't heard of it reacting to galvonised troughs but said if she heard different from one of the others she would ring me. I forgot to ask her if a dexter would be half dose but I asume so (Duncan what do you think?) Sorry to be a pain but I would like to get it right.

Saffy · Post by **Saffy** » Fri Mar 21, 2008 10:43 am

Colin,

Just because your cows haven’t had magnesium deficiency yet doesn’t necessarily mean that you are preventing it, it could just mean you have been lucky so far! I say this from hard experience!!! When I ran a large milking herd we would go years without getting one and then have two in a year, without having changed a thing.

Sorry to be so negative but it pays to stay vigilant and on the lookout for the early signs.

Stephanie

Saffy · Post by **Saffy** » Wed Apr 30, 2008 1:22 pm

As Spring ha ha, looks like it is going to be later this year I take it that means that any threat of Mag Def is likely to come later as well, so we should be vigilant later in to the year then usual?

Comments?

I fully intend to give mine Mag Rolls all year now I have found a source although I have to travel a 2 hour round trip to get them!