when does a pup show its gender

Question
Hi there Heather! thanks for the few times you helped me out previously. Bet you don't remember but that's ok!

as the subject says.. i have just got a little black bear pup.. probably around 2.5 weeks old (16-18 days)..

I'm hoping its a HE.. but it hasnt grown any testicles yet..

from your experience.. may i  know when is the average time they start showing gender?

thanks a lot in advance!! :)

Answer
You should be able to see a distinct difference between the guys and girls by day 28. Even with the absence of testicles you can use the anus and urethra distance to judge too.

http://t0.gstatic.com/images?q=tbn:ANd9GcR_DmNb7Wg_o1nocYQK402Ro_TNxAqX0ghLbLPKX...