problem with red eared slider

Question
Hello,

I have a RES that's 4 cm in length. It has vitamin insufficiency and pneumonia. We have tried feeding her liver food, pellets, cooked chicken meat and ham but the turtle doesn't even open it's mouth.

What can we do to make it open it's mouth? Would it be appropriate to inject calcium and vitamin D3 or the procedure on an animal this small is completely dangerous?  

Answer
Turtles are notoriously stubborn. I am not a turtle expert but I hope you are in consultation with a veterinarian.
The only way I know how to make one open their mouths is to gently squeeze the sides like you would a baby bird to make them 'gape'. Another thing you might want to do is to liquefy all the food and use a blunt syringe to get drops of this into her mouth.

You might want to repost in the reptile area here or call a vet that does reptiles. They will give you free advice on the phone.