If the horse is Ill and not responding to treatments provided by the owner then you need to call a Horse vet immediately.
First of all, I assume you are referring to the animal a 'horse', as 'hourse's do not so far exist to mankind. I also assume you mean 'illness'. 'Ilness' is not a word. Assuming that much, your question is unanswerable with the provided information. It depends on the illness, and the horse. I suggest having a vet check out the horse, so you can figure out what is wrong.
Horse Save
it is a pet ilness
disease .
what's wrong with the horse?
she had a mental break down
government and ilness.
click on the horse and in the corner there will be a spot to provide a offer and then save it
lung cancer
She died of an ilness,
What types of ilness is caused by phosphate?
a person who is weak with ilness