Do you know what is wrong with your calf? What specific illness are you treating him for?
It is a very good idea to check his temperature.
You could be dealing with something mechanical like hardware disease. He could have a virus and antibiotics won't kill a virus. However, antibiotics can help keep the calf from catching a secondary bacterial infection.
Is his illness respiratory? Is it intestinal? Has a vet examined him - listened to his lungs with a stethoscope, etc., and diagnosed an illness?
If he is too weak to eat and/or drink, he may need IV fluids for rehydration. An animal recovers from a viral infection simply because his body overcame the virus. The steps you are taking are supportive - helping to keep his strength up so he can fight the virus. He may also need some electrolytes tubed into him to help rehydrate and strengthen him.
Only your vet can advise you and only after the animal is examined.
> The first thing to do is check his
> temperature and make sure it is
> okay. Try giving him some
> different drugs like synergistryn
> and trivetron. I have found that
> they work well together. Just
> because nuflor and micotile are
> expensive they dont always work.