My dog has lost its appetite. Please help!?

My dog used to eat on its own and now we have to spoon feed him which he sometimes spit, this started from july when there was blood in his stools and doctors treated him and he was fine and then never blood came up in his tools, but the problem remained was he didn t eat on his self which he earlier used to do, the basic blood tests were normal including liver and kidney test except his eosinophils were low down to 1 and his mean cell packed volume was high to 25. I dont know whats wrong with him and he doesn t eat his food except his biscuits and earlier he used to eat royal canine and now he rejects that too and doesn t even drink much water, his stools appears to be normal (no test) he eats fast fods but reject other and he is a bit lethargic but when we play with him he is full charged with energy, he is properly vaccinated and he is not able to stand long on his two legs (i guess theres some prob. There too) . Please help. He is a Labrador retriever and is a male and 2 years old, thanks.