Male cats (neutered or not) can be prone to a blockage. This can be caused by crystals which are struvite or oxalate. The crystals build up and prevent Mr. Kitty from being able to urinate. This can be VERY painful and I have seen many cats lick their penis to try to aliviate the pain. If a cat is blocked, and does not get veterinary attention quickly, death can result. I do not say this to scare you, but it can happen. As for switching his food, some foods can cause a build up of crystals and cats that suffer from this are usually put on a special diet such as hills feline c/d, s/d (for struvites) and feline o/d (for oxolates). I would advise that you check your kitty's litter box to see if there is a normal amount of urine in it. Also, if he is going in and out of the litter box more than usual, it could be a sign of a blockage. Look also for any blood in the litter box. Either way, kitty should be seen by a Veterinarian to make sure everything is working properly and they can feel his bladder to make sure it is not too full and if it is, they can try to express his bladder and test the urine for the pH, as well as the specific gravity, blood, bacteria, etc. They will also spin the urine in a centerfuge and look at it under the microscope for crystals. If Mr. Kitty is blocked, they will usually insert a urinary catheter and some vets will suture it in, put kitty on iv fluids and antibiotics, and monitor urine output for a few days. If found in time, and treated properly, cats can lead a healthy and normal life with a special diet... I hope that this helps... I also hope Mr. Kitty feels better...
Sincerely,
Jennifer VT, ACO
Sincerely,
Jennifer VT, ACO