neutered but still aggressive

Question
I neutered a 2 to 3 year old tomcat, Frankie, 31 days ago.  He originally belonged to my niece when she lived on the property. She moved and Frankie stayed and became feral but kept his nice friendly behavior. I moved here last summer with my 4 cats and eventually Frankie decided he lived here, too, and moved back in permanently.  I allowed him to be indoor/outdoor since he had been feral for so long.  He was getting in fights so I finally got him neutered.  After 2 weeks I let him go outside and within 7 hours he was home with half ear tore and bloody mess from cat fight.  The vet said it takes 30 days for the hormones to change so I have kept him inside since then.  Now its 31 days I'd like to let him go outside because he begs and pleads with me - plus he picks fights with the dogs and one of my cats - although it appears to be mostly anger at not being allowed to go outside.  He constantly had the attitude "please let me out".  Frankie took Amoxicillin at time he was fixed because he just had been in cat fight and then had to take another bottle for 10 days after his 2nd fight (2 weeks following the neuter). If I let him out and he gets in another fight then I guess its another bottle of Amoxicillin but I don't really have the money for that plus there is so much blood to deal with.  The tech at the vet said she'd probably keep him in an extra week which I am willing to do if someone tells me I should but its so sad to see him beg, I'd like to let him out. Plus my cats have controlled time to go out and play and he sees this and gets jealous.  [They are not truly outdoor cats but get a couple hours a day of play time outside.  They stay close to the house.]  We live in the country on 3 acres.  Please tell me if you think more time indoors won't make a difference now.  I do understand that he may never stop fighting.  Thank you for your opinion and help.

Answer
Sheila,

Sometimes it can take up to 6-7 weeks for hormones to drop off and aggression to gradually disappear. It's quite possible that keeping this kitty indoors for awhile longer or only allowing him outdoors on a leash when he can be supervised by someone would be smartest and help to prevent further fights. Unfortunately the fact that Frankie was well established in terms of territorial aggression with other cats may mean that he never does stop fighting, if this is the case it would probably be best for Frankie, your pocket book and Frankie's continued health to live the rest of his life indoors with only supervised and controlled outdoor excursions. Harness training Frankie and putting him on a leash will allow you to walk him around the yard, he gets to go outside and enjoy all of the smells and you don't have to worry about future injuries or health problems such as feline leukemia and FIV which are viral infections similar to HIV/AIDS in people (don't worry these can't be passed on to people) can be contracted through fighting.