With your help he will. Cat saliva is contagious and very dangerous for your bird.
Please treat wounds with saline solution to clean them no matter how small.
Afterwards you need to put on wounds antibacterial cream.
You need to give your bird antibiotic too it is called Clavamox or Synulox (amoxicillin with clavulanic acid) against bacteria in the cat's saliva.
You need to do this as soon as possible. Vet will be able to help you but it needs to be avian vet or someone with experience with birds. That leg should be checked, maybe it is not broken, otherwise it should be fixed in cast.
Vet will be able to help you and will have medicines needed. Be aware though that some Vets like to take shortcuts and hasten to put birds to sleep. Do not allow them to kill your bird. Cleaning of wounds, bandage for broken wings and legs and antibiotic treatment give your bird chances to survive.
One more thing. Bird is most probably in shock. Do not disturb him unless for medical treatment. On later stage you may provide water and food and even to hand feed him, but wounds are priority now.
Keep me posted, ill try to help however I can.
Your pigeon needs Clavamox ASAP for the cat wounds. And I'm sorry; I forget what it's called in the UK, but someone should be along soon who can help. Even a non-avian vet should be able to prescribe it. It's very important you get him started on the antibiotic right away because cats can carry pasteurella in their saliva and it's deadly to birds.
Right just an update on our baby - sorry for mis writing she is actually a she i was in a rush when i posted....she has made it through the night, she looks comfortable and we are heading to the vet with her this morning.
She spent all evening wrapped up warm in our beroom (quietest place) and i put a small amount of food and water out for her late last night, this morning she's obviously been moving around as sheis unwrapped from the towel. She looks bright and alert and doesnt seem stressed so im hoping she isnt in too much pain. Her injuries may not be as bad as i think but im no expert on bird injuries, also i dont wanna keep looking so not to hurt her or do any damage!
So we will be getting her to the vet very shortly.
I will bare what you said in mind Plamenh - thanks, i will make them give her a chance, she's beautiful, we breed white racers and she came out black and white ( her mother has one black feather so must come from her) but she's gorgeous.
Thanks so much for your help i will post again after our vet trip to let you know the news.
Its fab to know there is somewhere i can come for help, pigeon keeping really is a steep learning curve!