Here is a problem with my dog,that due to his diseases my other pets are always aggressive at him, my cat and dog are not
spent a single minute together with each. not easy to manage them at same time, some time cat cut at his body but he just bark and not
hit her so what is the process to train our pet or hire a good trainer for pets.....
You can establish yourself as the pack leader and protect him in their presence and they will respect that even when you are not around. I've done it when introducing new pups to older dogs and even introducing kittens to dogs....make sure they know you own that animal and that it is then under your protection. It works also when training dogs around chickens.
Just gotta establish some order and let everyone know who's the boss in your house...the animals or you. It's a good idea to watch or read a little of the techniques of Cesar Milan..he's pretty good at showing how to do this.
I agree with protecting the "underdog" pet. That's always worked well for me with cats and dogs. Basically "shelter" your dog with your body and arms and push the aggressor away. With kittens/cats you can escalate to giving them a solid tap on the nose just between the eyes. Not hard, just firm with a finger or 2. I learned that from watching our older cats discipline kittens (heck the older cats are way rougher than I am and the kittens cope with it!)
No advice on dog trainers. Not sure how that would help as your cat needs the training.
The Greenhouse of the Future ebook by Francis Gendron