During the journey itself it must be seen that the animals have sufficient food and water. If possible, a magnesium supplement should naturally be offered. The only practical method appears to be to feed a concentrate containing magnesium. The normal therapeutic treatment consists in injecting magnesium and calcium salt simultaneously, as in the case of grass tetany. Spring grass tetany appears to be the most frequent in N.W. Europe, although this is not a general rule.
Some authors even define a summer tetany.
Hypomagnesaemia, developing particularly in regions where stock graze the whole year through. Hypomagnesaemia of the intermediate type in which the magnesium level in the blood serum does not fall as rapidly as in the acute form, but less slowly than in the second case. This form occurs in the Low Countries in dairy cows on summer pastures. He thinks this is a case of latent tetany and that any change in climate or alteration in the quality of the pasture grass can trigger the attack. It must be remembered, moreover, that winter grass not only has a high moisture content but is also very low in crude fibre and energy due to the low intensity of sunlight.