Ok I have a 10 year old who has been spayed for 4 years, I know she was, I was there and we did this during a C section. My question is whenever 1 of my girls come in season the boys go after the old gal. Vet sees lots of bacteria in her urine. She is on meds again. Could this be from food? She has been Pro Plan Senior for years.

Bacteria in urine is usualy a UTI and she may just be prone to them in her senior years. I don't see food being the cause in my experience.

I would get her on crancaps daily and check urine PH at home and see how you do.

That would be my first step to stay off meds.

I don't see the bacteria drawing in the boys, but I don't have boys here.

I agree with the cran caps and checking the urine pH. Food can be an issue causing the urine pH to be too high, however the cranberry may help with that. Years ago I had a bitch that could not tolerate certain foods, they caused the pH to be to high and in turn caused UTIs. You should also try adding vit C to help with bringing down the pH.

Yes, the boys can pick up on the bacteria.