Hair Loss on a baby pig

Question
Hi
My sow (Brandy) gave birth on christmas day without any problems whatsoever to 4 little piggies. They are gorgeous and all eating, suckling and running around well. Out of the 4 babies there was a runt. He/she's been fine, messing about with the others,suckling etc until today when i noticed the hair is starting to thin all over his/her little body. He/she is smaller than the other three but i just thought he/she might be a late developer. Why do you think this hair loss is happening? He/she is still hopping around and eating/suckling well although he/she'd rather suckle than eat hay or pellets. Will the pig lose all his hair? Would it grow back when he/she's a bit older. They are all only 4 days old but just wondered why this was happening.
Thank you for your time x

Answer
Hi Felicia,

    It is normal for there to be a smaller, less active runt in a litter of four.  Be sure that he is getting as much nutrients as the rest of the guinea pigs, because one big cause of hair loss is vitamin deficiency.  If necessary, remove the other pups for a few minutes to ensure that the runt gets some alone time with mom.  Stress is also a leading cause of hair loss - observe the way he is being treated by the mother and the rest of the litter.  If the problem persists, seek veterinary help from a vet who is experienced in the area of guinea pigs.

    Thank you for your question, I hope I have been of some help to you.  If you have any further questions, please do not hesitate to ask.  Good luck with your guinea pigs (=

                                                 - Nicole