Again still no further forward! Nothing significant was found on the ultrasound scan, apart from a tiny polyp in Ozzy's bladder. Nothing at all to worry about, and certainly not the cause of the dilute urine. X-ray of his chest was also clear. Also found was some calcification on his kidneys, but again, due to his excess lipids, that was entirely expected and not significant apparently. So, we are none the wiser. Steve also emptied his anal glands while he was sedated and had a good feel to check for lumps, but found none. He also took a sample of urine direct from his bladder and sent that off for culture, but it came back clear. I then had to collect a small sample of urine every day for 3 days, which was then mixed together to check for an average steroid count, which we are waiting for the result of. Not sure yet where we go from here, but Ozzy doesn't seem to be drinking as much any more, or asking to go out as often either, so possibly it might just have been a transient thing which we might never know the cause of. Vet Steve is on paternity leave at the moment, so Ozzy is being dealt with by one of the other vets who we don't know, so unless something significant turns up in the latest sample then I expect we'll just leave things as they are until Steve is back.