Hi just been reading a website which vanulla ice cream is good to give a bitch during whelping beacuase it hydrates them gives glucose for energy amd also a calcium boost which will help the parathyriod gland to release to a hormone from her bones to help with muscle and pushing just wondered if anyone had ever heard of this.

There is no necessity to give a bitch calcium.  Indeed, it can actually cause problems with eclampsia. 

Assuming that a pregnant bitch is on a quality puppy food, the balance of nutrients is correct for what she needs.  We don't need to supplement.

A lot of us do put a teaspoon of glucose powder in the bitches drinking water.  Works for some, if the bitch wants to drink.  Others can steadfastly refuse it, even if you hold the bowl under their noses.