Steven Butlerjohn's answer is spot on. the advantage of a Enzyme it will break down the proteins which are the problem here. mak sure you vac wilh hepa filter as you dont want to put all the proteins into the air and for them to land on every other surface then to be disturbed and breathed in later. Good Luck
As a lot of Dogs have oily coats, this often gets transferred to the carpet fibres. There are two ways to go. You can use an Enzyme Pre spray and the Enzyme will break down the oily residues for removal. Or you can use a Citrus type Pre Spray and the degreasing action will achieve the same result.