behavior after mating

Question
I have a 4 month standard poodle that a friends would like to mate with her 2 yr old lab.  How old should he be before we consider mating and what will his behavior be like if we mate him when he is still young.  Will he still what to mark his territory?

Answer
Well first I feel that it must be said that you shouldnt be mating 2 different breeds like this.  If you want to help out mixed breeds then go pick one up at your local shelter.   Their is no reason to be breeding a lab to a poodle.  This is a designer dog... "A mutt" and doesnt serve a purpose.  Secondly a standard poodle should never be bred until it is 2 years old and has its genetic testing done to make sure that you are not passing on terrible genetic defects.  Especially hip dysplasia.  This lab should also never be bred until his genetic testing is also finished.  Most male standard poodles arent sexually mature until after 12 months of age to even attempt a breeding.
There are a lot of things to concider and research before even thinking about breeding.  Please do some reasearch and seriously ask yourself if you are willing to take on this responsibility before even concidering it.  It is not a thing to take lightly and it is a very expensive labor of love.  You should always breed to improve the breed.
Yes most males that are kept intact and used for breeding purposes WILL mark their teritory.  Its a matter of teaching them not to do it.
However since you are asking these questions I see that you are not sure about doing this breeding.  If there are any doubts in your mind that should tell you right there that you should NOT be breeding.