There’s a real art and a science to looking after cows in the lead-up to, and just after, calving. As you can imagine, cows need an incredible amount of calcium to both grow their calves and to produce milk.
You’d think that adding extra calcium in their diets would be a good idea, wouldn’t you? Well, actually vets tell us that adding calcium is one of the worst things you can do to a cow that’s about to calve. It makes her much more likely to suffer from a life-threatening disorder called “milk fever”, where the body cannot produce enough calcium to power her muscles (including the heart).
Instead, we must choose feeds that encourage the cow’s body to draw calcium from her bones and that will help her adjust to the diet she’ll receive as a member of the milking herd. If we don’t get the feeding regime right during the two to three weeks before calving, cows are more likely to have trouble calving, develop lameness, lose weight, produce less milk and get sick with mastitis.
Ironically, too much grass at this time also spells big trouble. It generally has a high dietary cation anion difference (DCAD), which doesn’t help get precious calcium into the bloodstream. That’s why cows in our calving paddock have access to short but clean grass, anion salts in their drinking water, cereal hay and half the ration of grain they’ll get in the dairy. They’re too precious to treat with any less TLC.