Cocker Spaniel Heat Cycle

Question
I have a 4 month old female partie cocker puppy.  At least we have been told she is a partie cocker.  Anyway, I was wondering if someone could tell me when she will come into her first heat cycle? And is there a form of birth control for female dogs?  We have a registered male Chocolate Lab as well and I do not want to mix the two together!  He is not neutered since he is occasionally used for stud.  He is 8 years old and figured it is a little late in life to neuter him.  We wish to breed our cocker when she gets older to a friends male who is still a puppy as well.  Aside from keeping them locked apart or fixing one of them, is there a form of birth control that is safe and reliable for dogs?  Any help before I track down my vet with this would be great. Thank you

Answer
She'll come into heat "around" 6 months.  As far as I know there's no birth control for dogs.

I'd think twice about breeding unless both cockers come from responsible breeders who can guarantee their health profiles.
Irresponsible breeders are hugely responsible for the long, long list of health issues cockers now have.
Delores