Take it to the Veterinarian immediately. Period.
No, my dog has not been attacked by a cat recently.
We do not know where you live. It could have been anything from a roaming cat, to a snake, to another species of bird. There is no way to tell, given the information you supplied.
it probally attacked you when you meowed because it thought you was another cat.
They believe he was attacked by some sort of animal
I have usually found dogs attack newborn kittens and Indian Minors. My cat has been attacked by a dog and an Indian Minor. It is quite scary watching him getting attacked but I shooed away the birds but there was really nothing I could do when the dog attacked. My cat got a few scratches around his mouth from he dog.
It is possible that your dog has been injured after being attacked by a cat. It is important to carefully examine your dog for any signs of injury and seek veterinary attention if needed.
another cat
Yes, a cat has attacked a dog in my presence.
If the cat is yours i would say call someone to remove the cat and put it to sleep, but if it doesn't belong to you call your local animal control.
You should pet her and make her sit on your lap so that she feels secure. Give her something to eat and try to console her.
I think that most cats will hiss at another animal or cat if they were not brought up with another animal or cat. My cat is not Siamese, and she hisses at other animals and other cats, so I think that it is normal behavior for all cats, not just Siamese cats.
jaguar cat cheetah lion kitten puma panther