I have two labs, Rosie is 7 months old and just come into her first season, she was supposed to be spayed in 2 weeks time but its a bit late now! Our other dog, Jasper is 5 months old and doesnt seem to be taking any interest in her at all, is he too young to be interested or is he likely to have a go? If so do i have to seperate them? And how will i know if the deed has already been done? Any advise would be welcome as i am new to dog owning and know very little this subject.

He is young but it is certainly not impossible, there is little way of knowing for sure whether anything has happened yet.  If you think anything may have happened, there are mismate injections available from your Vet, but there is a timescale of opportunity.  From now on keep them seperated when you are not there, and not just with baby gates, a Lab could easily jump one if the temptation was great enough
Good luck, you will be able to get her spayed between seasons, so you don't have to do this again!
Hayley

Make sure that you wait at least four months before you have her spayed now. That allows for all her hormones to settle back down. I fully believe that you shouldn't have a bitch spayed until she has had her first season. She will always calm down a bit after a season, she will be now fully grown before she is spayed and her hormones will now be in the right place.

You 5 month boy (if he is a typical 5 month) shouldn't be too bothered about it. The time that he might be will be from about day 8 onwards. Remember when she isn't loosing to much (which is from about that day) doesn't mean she has finished, she will then be in the mating stage and this can go on to sometimes day 21 but usually 17, but I would be careful to day 21. Remember no walks where other people go with dogs because it will cause awful problems.

Hope this helps

Five months is plenty old enough for him to be able to sire a litter, so never leave them together unattended. It will be better for them both if you separate them before he starts getting interested - once he's got the idea in his head you could have him continually howling like a wolf until she's out of season (very wearing on the nerves for everyone, including the neighbours). If they are never unattended, not even for a second, you will know that the deed hasn't been done!

Has any one even bothered to say that Yes they can breed at 5 Months BUT it is Very Harmful to the Male dog!!!..You should Never Breed with a Dog on their First Heat she is Still only a Baby at least her second or third, she will handle it alot better and also you are not Surpose to Breed with any MAle under the Age of Two...Give them a Chance to grow them self's, so don't be in a Harry

<<<<<<<<<not Surpose to Breed with any MAle under the Age of Two>>>>>>>>>
Don't know where you are jellybean_oz but in the UK it is more than acceptable to use a male from approx 12 months old as long as all relevant health tests are completed...in fact 2 years to start a stud carrer if the dog is doing well and the owners intend on him being used regularly could be considered on the late side
However most responsible breeders would not consider breeding from a bitch before her 3rd season or 2 years of age...which ever came first.
Archer

well said Archer.

also jellybean, the OP was not intending for the 2 dogs to be mated, but was asking for advice if this were possible.

& just to add, it is possible for him to mate her so be very careful over the next 4 weeks.  :)

Oh Yappy!  nobody bothered to tell my bitch she was supposed to calm down after her first season!  She's had 4 and is as mad as ever!

You've got me worried now. My 18 month bitch should have been in season by now and my dog puppy is 15 weeks old. When is it possible for him to do the deed? I was told I was OK until he was 6 months.We're having her spayed after her season BTW.