leash agression - part 2

Question
Hello, I just wrote you the question about the Chinese crested powder puff w/ leash aggression.  There are a few more details I decide might may help you better answer my questions.  I got him in Oct from a family who loved him but couldn't give him enough attention.  They also had a larger male dog that used to "pick on him"  I didn't get any details on what that meant.  They were using him as a breeder so he was not fixed.  I got him neutered in dec.  A few weeks after that I took him to doggie day care for a week over xmas.  Once I got him back is when I started to notice the aggression.  The people at the day care said he got along w/ everyone except 1 dog but that he was very kennel aggressive.  Why did he get more aggressive AFTER neutering?  Is is possible that going to this day care kind of "awoke his dominate self" which he couldn't display before because he lived with another dog that was more dominate?  Like I said, I got him in Oct and he wasn't displaying these tenancies at the time.  I can't pin point exactly when it started but it was def around the time after he got back from a week at the kennel place.

Answer
Neutering can, INFREQUENTLY, increase aggression but in this case I strongly doubt it.  Your dog is just now settling in with you and I suspect you are not giving him strong enough signals of safety (not uncommon, don't beat yourself up!)  Follow the suggestions I just offered and, in addition to those, institute (at HOME) a strong signal that you are higher ranking by making him earn his food (use the clicker to teach a strong "sit") and WIN all games you play with him by keeping the toy at the end of the game.  This will help to calm him (he seems to have come from a chaotic former home and may be desperately trying to step up in rank).  Repost with any further questions.