Maine Coon male marking his territory?

[dantm]

Hello,

We have 3 MC, a 6 year old girl, a 1 year old boy, and a 10 month old girl. The girls have been spayed whereas the boy has not been neutered as we've been waiting as long as possible to do so. They are all indoor cats and live in a very clean environment; and since we want minimal intervention on them we had wanted to delay the neutering. We did spay the younger girl since we do want to avoid any pregnancy issues inside the MC household.

However, in the last week or so we've noticed the non-neutered male urinate outside his box, typically in different corners of the house. We have a huge sandbox (largest storage-type container) which is cleaned very often so it's not the box that is dirty. The other two MCs go to the box regularly as does he, but half of his #1 I would say is now done in different corners of the house.

Is this an indication of sexual maturity and would neutering help with it? Is there any way to avoid neutering -- basically we do not need it for population control/etc.

Finally, even though I personally doubt it - could this be due to a change in the diet or a UTI? We've recently gone from Royal Canine MC + Fancy Feast Beef to a River Ranch dry + raw chicken + fish oil supplements for all the MCs.

Thank you.