The female cat got spayed at Humane Ohio. Since then she did not meow anymore. I have been observing her and noticed she tries to meow but it comes out soundless, no noise, just the air pssing through. Is possible the vocal cords or vocal nerves got damaged? Is there any treatment? is this damage reversible?. She still can purrs and hiss. How can I find out if there is permanent or temporary damage?- Please, help.