Neutered dog peeing in the house

Question
Hi Nancy,

I have a 7 month old pointer/beagle (we are guessing) mix.  He has been housebroken for about 2 months now, with only one accident inside in that time period.  He was neutered almost two weeks ago (March 15) and since then has been peeing inside the house/ in the hallway in our apartment complex.  He will "hold" it all night, for up to 9 hours (usually 7-8) no problem, and always pee outside in the morning.  But, during the day he will pee inside despite going out every 2-4 hours.  It is always when I am in the process of taking him out- I will put his leash on, and sometimes he will pee by the door or in the hallway when we are waiting for the elevator (in our building).  I always catch him in the act and I discipline him, mostly by saying "NO" and then putting him in time out.  I also give him positive reinforcement when he goes appropriately outside.

Could the neutering have affected his bladder?  I am confused because he can hold it for a solid length of time every night, but then he is unable to hold it for 2-3 hours during the day.  Is it possible that he has a bladder infection or something?  He shows no other symptoms of anything being wrong.  

Thank you so much for taking the time to read this-
Best,
Carolynn

Answer
Oops! You didn't get one of the Nancys....  :)

First I would have him checked to make sure that he doesn't have a bladder infection. If that is not the problem, then start housebreaking him again. Sometimes youngsters just need to be reminded what they are supposed to do (or not do). Just being at the vet in a cage for a day or two could have been enough to confuse him.

As he gets older, he may be starting to mark, although he is a bit young for that (unless he is a fairly dominant dog). It may also be that another dog in the building has already marked in those areas, and he is just copying them. If he is small enough, I would carry him outside. If he is too large to carry, keep him on a very short leash, and insist that he sit whenever you stop. Most males won't urinate when they are sitting. Try to anticipate him; most will sniff before peeing. If you suspect that he is thinking of marking, you can remind him NOT TO GO, possibly before he even thinks about "doing the deed". A bit of a pop with the lead to get his attention, along with a verbal "Ah, ah, ahhh...." may be all he will need.