about spaying

Question
do dogs get depressed once they no that they wont have babies ..will their age decrease ???

Answer
No, dogs do not get depressed when they don't reproduce.  They are not rational thinking beings.  Instinct causes them to reproduce not rational (or irrational) thoughts about wanting to have children like humans do.  

Their lifespan can actually INCREASE if they are desexed because males and females have been known to wander and get hurt/killed when they are following a scent that tells them to breed.