old dog wandering

Question
Hi there.  I have a weird situation.  I have a 17 yr old terri-poo mix male. HIs name is Scruffy.  We raised him from 6 weeks old. He has NEVER been tied up and has NEVER left the boundaries of our yard and driveway. I always went out with him when he was a pup and he learned the perimeters. Even when my Dad tried enticing him with cookies (they live 2 doors down) he would not leave the yard.  Same as other dogs going by, he sits like a gopher and waits for them to get here to say "hi".   Past few weeks Scruffy has taken to wandering and is gone for anywhere from half hour to 6 hours.  We have NO idea where he is going.   He disappears so fast.  But when he comes back it's like he doesn't know he did wrong.  He ALWAYS knew in the past-----head hangs down, tail between legs, and goes straight to his bed.  No hitting him or anaything, you just have to ask him if he did something bad and he is like a child -- you KNOW right away and so did he. But NOT after these wandering episodes.    5 times in past 2 weeks.  We have started tying him now and of course he hates it.  He is totally a suck and inside dog who sleeps with us and goes fishing with us and even goes to Tim Hortons for his donut with us.  He was never neutered and we have never, ever had a problem with females dogs, humping or any other breeding instinct.  Which was just fine far as I could see.     Can this perhaps be senility at his age?   We are very confused as to why all of a sudden.   Healthwise he is THE healthiest dog you ever saw over past 17 years.

Answer
Honestly, it does sound like he's developing dementia, Eva. I don't think he knows he's wandering off. When I was growing up we had a chi-poo that, like your dog, never left the yard until she got up in years. When she was around 12 or 13, I guess, she started wandering off more and more frequently. She ended up in the culvert that went underneath our driveway several times, not knowing how to get back out again. We had to start putting her in a pen when we let her out and weren't going to be out there with her.

You may want to consider having your boy neutered, as the risk of prostate and testicular cancer increases drastically with old age. It might be something to talk to your vet about. They may not want to do it since he's so old now, but it wouldn't hurt to ask.