sir,

Question
two months back a dog attack my duck
and injured its neck and face.now the wound is to some extent filled but the duck feels difficult to eat something and to open its beak.and there is no vet doctor around us...reply me soon

Answer
I am not a sir, but I also cannot tell you much about this wound since I cannot see it. You might want to re-post this the area about birds.
Here is the link:

http://www.allexperts.com/el/Birds-General/

the top lady does ducks/geese/chickens

or here:

http://www.justanswer.com/questions/1y4o3-baby-duck-injury

If not you need to call a vet somewhere around you and ask them the same question. If the duck is eating and drinking there is probably nothing more to be done. The problem the duck is having is probably from scar tissue. That is about the only thing I can tell you about it.

Sorry I could not be more helpful.