Whats the topic for today?
Puerperal Tetany in the bitch.
That’s a very technical name? Does it have a simpler name?
Well that’s no better. What is it?
It refers to a dangerous drop in blood calcium levels that can occur around the time of whelping.
What problem does it cause?
The main effect is on nerve conduction and muscle contraction so you see a dog that starts to tremble with uncontrolled muscle contractions. The muscles can go into spasms just like you see in tetanus.
Is it dangerous?
Yes it’s an emergency life threatening situation. In the early stages you see trembling and incoordination but it leads to seizures and death.
Is it treatable?
Thankfully yes if you catch it soon enough. We need to give intravenous calcium and this reverses the symptoms pretty quickly. But then we need to monitor the situation carefully as the calcium levels can drop again.
How long do they need treatment for?
It varies a lot. Some bitches may just need one treatment whereas others may take a week before they are under control again.
You said it happens around the time of whelping. Why is that?
The bitch starts to make a lot of milk around whelping time and this milk is full of calcium so the bitches need for calcium increases. Eclampsia can start just before whelping but the commonest time is about 2-3 weeks after whelping when the milk production is at its highest.
What exactly is it that causes eclampsia in some bitches whereas others are ok?
Usually the blood calcium level is very well controlled. When the body needs more calcium parathyroid hormone increase the amount of calcium absorbed by the gut and also causes calcium to be mobilised from the bones. The bones act as a store of calcium. Sometimes it takes a few days for this control mechanism to kick in and it is this time lapse that causes some bitches to have a problem.
So couldn’t all this be prevented by giving the bitch extra calcium in her food whilst she is pregnant?
No. It s been shown that giving calcium supplements during pregnancy actually increases the risk of eclampsia at whelping.
How can that be?
When you supplement with calcium the parathyroid control mechanism sort of goes to sleep as it isnt needed. Then when there is a sudden need for increased calcium during lactation it actually takes longer for that control mechanism to kick start into action again.
So what is the best thing to do to prevent eclampsia?
During pregnancy and lactation you need to feed a high energy diet that has adequate but not excess calcium. An ideal diet is actually one thats designed for the growing puppy and we recommend feeding the pregnant bitch with a good quality puppy food.
What about after whelping?
Carry on with the same diet until the pups have been weaned. After whelping it is actually safe to start giving a calcium supplement and this is recommended if the bitch has had eclampsia before or if she is feeding a large litter.
Does having a large litter make the bitch more likely to get eclampsia?
Yes. Small breed dogs with a large litter are at the highest risk. It is advisable with large litters to supplement the pups with a commercial puppy milk to take the pressure off the bitch. If the bitch gets eclampsia then the pups must be taken off her emmediately and hand raised on puppy milk.
So whats the take home message for today?
Don’t give calcium supplements during pregnancy but use a good quality puppy food.
And if you see muscle trembling around the time of whelping treat it as an emergency and see your vet.