young female with male dog neighbors and heat

Question
I am wondering at what age a female golden retriever will go into heat.  She is outside a lot and seemed to have a slight discharge and she is only 5 months old.  At what age is it healthy for her to be bred?  At what age can she actually get pregnant since she is outside a lot and in the country, I don't want the neighbors' hound dog visiting.
Thanks!

Answer
Females seldom come into season before 7 months.  I would have the the vet look at any discharge now.  You would be much better off getting her spayed now.  Breeding should be left to those not needing to ask simple, basic questions. Books have been written about it.  Those unwilling to do the work it takes to produce quality puppies should spay/neuter their pets at 6 months.

To understand my position check both http://www.woodhavenlabs.com/articles.html#breeding and www.petfinders.org''