How to prevent milk fever??

Hello everyone. I'm new here. I wanted some advice on how to prevent my queen from another calcium deficiency. I had to rush her to the vet last year after her kittens were 4 weeks old. I found her on the floor not really moving. She had urinated and was growling. Started seizing. Pupils were enormous. The vet told me he thought she was already dying. Her heart beat was still strong even though her body temp was deathly low. At first he thought she had ingested something that make her sick, but there was no evidence and he never did a blood test. He warmed her up and gave her iv fluids with calcium and glucose. Also gave her diazepam for the seizures. He said the only thing he could think of for her near death experience is that she might have had milk fever. Yet he said the really strange thing is that her body temperature was so low. Usually they contract a high fever with that illness. Is there a way to make sure she has special nutrition this time around? I  do not want her to go through that again. it was a very scary experience for both of us. Any advice on extra nutrition is welcome. I want to make sure she does not have this issue ever again. Thank you.

Im not sure if milk fever and calcium deficiency is the same*...  What you describe is calcium deficiency - which may be serious yes...  I think even there is a good article on it here on TCS somewhere, I did some proofreeding some year ago.

What exactly is she eating?

Otherwise, if you think calcium shortage may be a problem - and the demands are bigger and bigger, the biggest shortly before the kittens get weaned - you make sure she gets some extra calcium...

There are special preparates containing calcium, like  pulverised bones,  and others.  Good pet shops, and good shops for health minded people carry such.

Otherwise, natural foods, like, goat milk, cheese, youghurt, even cow milk if you are entirely sure she managed cow milk...  Take some nice full fat verision.  No funny diet reduced  fat versions in any of these examples.

None of these can hurt, may help, all may without troubles be part of her daily diet.

ps.  Nay, I see its the same...   Sorry.