best food for golden retriever pup

Question
My pup is female, 5 months old and not yet spayed. She continues to have runny
poop. I am feeding her Iams puppy food. Is there a certain food that will be
easier for her to digest or is it normal for her poop to constantly be runny? She
is covered under a medical plan and is current with all vaccinations and
worming. Thank you.

Answer
Parasites are a more likely cause of runny stools than food.  Have your vet check, and recheck a stool sample.  Maybe even try a different vet.  Switching to an adult chow for the larger breeds at 4 months, slows growth and helps develop sturdier joints.
Your dog definitely should be narrower at the waist than the hips and chest. You should be able to easily feel the ribs, but not see them. Each dog is different. Standard recommendations are a good place to start, but each dog must have its food and exercise adjusted to its individual needs. Here is a link to a good illustrated guide, http://www.longliveyourdog.com/twoplus/RateYourDog.aspx  I have heard that over feeding causes soft stools too.  
If nothing else helps, switch to a different adult chow.  If you are feeding the common lamb and rice Iams, a good choice might be Pro Plan chicken and rice.  Note, my 4 month old Golden is on the adult Iams lamb and rice.

You might also try a bland diet.  If chow is the problem, it should firm her up.  

Bland recovery diet for dogs.

3 parts cooked rice, one part boiled hamburger or chicken, or cottage cheese. I think you can substitute boiled potatoes for the rice. Once in an emergency, we bought a plain baked potato from Wendy's.

This is meant for short time settling a dog's digestive tract. It is not the complete and balanced diet they need long term. I have seen it work.