my sisters bitch gave birth this morning to 5 pups but sadly one died. It was born with its intestine and heart on the outside of its body, what would have caused this, or is it hereditory?

This happens from time to time and is dddddown to something happening during the fetal development, as far as I know it isn't hereditary but an unfortunate happening.

One of the two pups that a freinds bitch had despite having the antimate jab after a misalliance was born like this, so it does make me wonder if it could be chemically or hormonally induced.

This happens in all species, I was chairperson of a national childrens charity for children born with this condition. It isn't hereditary. What happens is when a baby is developing in the womb the internal organs develop first, then the muscle and finally the skin grow over the organs. The severity of the gap in the muscle and skin is down to the development stage. For some reason some baby animals and human children the development stops or slows down.

The condition in humans, (and I would suspect in animals), is connected to umbilical hernias as this is what this is sometimes referred to as. The muscle and skin finish developing at the umbilicus.

In humans there are two types of condition, one is gastroschisis, where the organs and intestines to a greater or lesser degree are outside the body, and floating loosely around, often getting damaged at birth and intestinal drying once exposed to air can be a problem leading to removal of a quantity of gut. The other condition is exomphalos were the organs and gut are contained in a thin membrane at birth and are less likely to suffer damage. With these conditions depending on the severity, the muscle and skin can be pulled across the gap and sewn closed. If the exomphalos or gastroschisis is large it is usually suspended above the baby in a sort of "teabag like" affair and the gut and organs drop slowly back into the body cavity, then the hole is closed, sometimes with muscle and skin, but where there is not enough a special mesh is placed over the hole which parents need to clean daily. (See www.geeps.co.uk)

In an animal it would be impossible to immobalise it to do much in the way of repair. For breeds with umbilical hernia problems I would assume, that these conditions would be more of a potential problem, especially if breeders were not working to eradicate umbilical hernias.