Altitude of zoo, can tha be limiting factor for successfull keeping and breeding?

I said that I think Cheyenne Mountain is #1 and that might even still be true...either way the zoo is #1 or #2 and you are nitpicking the details. On the zoo's website it mentions the "renowned giraffe herd - the largest at any zoo" but again I think that they are #1 in that category but perhaps there is another zoo out there in the world that would argue otherwise.

This particular link lists 17 giraffes at the zoo, although I believe it is a bit outdated as the last birth listed is in the summer of 2013:

Giraffe Facts | CMZoo

 

Oh, I‘m not nitpicking; I‘m just gently poking fun at your tendency to declare zoo superlatives and rankings (usually with, given your activity radius, considerable focus on North American institutions). No hard feelings. ^^

 

A whopping 40 to 60 giraffes? Wow. I have two words for Cheyenne Mountain Zoo: "American propaganda!"