I am a breeder and I absolutely love chihuahua's, My best guess is 4-9 years old just because they might have complications(for Male). for the female it is best to weait at least 2-8 years.
a male chihuahua will mate with a female chihuahua when she is in heat (AKA ovulating, on her period) they can sense it and then have the urge to mate.
if the chihuahua is a male
The two species are too diverse to mate and produce young.
yes, if you want to
NO! If they are both fixed, they CANNOT MATE!
What complications can happen to a female chihuahua when giving birth and during pregnancy!!!
They can mate with other dogs. Now, if you mean in terms of bloodlines and papers, then likely other Chihuahua-Yorkshires.
Puppies or Pups.
The fish has to be any age but not a baby! But Not to old either neither too young!
Yes there will be! It will come out in 2013 but not sure of the month yet. It's called "Chihuahua Too!"
best time is 3 years. maybe 2. ask the vet.
OF COURSE NOT!!!!!!