Milk fever is hypocalcemia. Grass tetany is hypomagnesemia.

Milk fever can be caused by feeding a high Ca diet to a dry cow. The theory has been that when a high calcium diet is fed during periods of low calcium demand, the cow's system is not "geared up" to efficiently use calcium. When her demand for calcium increases suddenly as she comes into lactation, if she has been on a high calcium diet she is not able to quickly and efficienty move calcium from the bones which can result in milk fever. By feeding a low calcium diet to a dry cow, she is able to mobilize and conserve calcium more efficiently when the demand increases and then you should increase the Ca intake. There is some more recent research that other mineral levels in the dry period may also contribute. Of course, I doubt we know the requirements of a deer for any of those minerals either.

Here is a cut and paste:

Management of the diet can be a valuable aid preventing milk fever. Cows should be kept on a low calcium diet while they are lactating (dry). This stimulates their calcium regulatory system to keep the blood levels normal by mobilising the body stores of calcium from the bone. When the demand for calcium increases as calving, calcium can be mobilised much more rapidly from bone than the feed, therefore preventing milk fever.

With cows at greater risk - Jersey cows of mature age and in forward to fat condition - green feed should be restricted and plenty of hay fed for at least 1-2 weeks before calving. Neither should contain a high percentage of clover or capeweed.

If it is necessary to improve the body condition of cows in order to improve milking performance, feeds high in energy but low in calcium may be used, for example cereal grain or oaten hay. Cereal grain is also high in phosphorus content, and this is of additional value.

Cows close to calving should be kept in a handy paddock to enable frequent observation and early detection of milk fever. On the point of calving, and afterwards, the available feed and calcium should be unrestricted. Calcium feed supplements may be helpful at this point, but should not be given earlier.




Also, you can dang sure poison a sheep with copper containing minerals on our soils. Sheep aren't cattle. Deer aren't cattle either...so what are the requirements for a deer and what levels are toxic?

Last edited by jlccoffee; 03/15/12 09:54 PM.