If you dream of having a cow in your backyard, it can mean you have good fortune. The dream symbolism of a cow means you have a useful, farm animal. The cow can give milk while alive, and after being slaughtered, it yields its meat and hide for leather. The dream symbol of cow most likely means you have a cash cow, or a good idea, that gives you money.
If you had been worried about your finances, this may trigger the dream of a cow. Your inner consciousness sends a message of your having at least one viable idea or possession that generates some money for you. You may have to think about what your brain is telling you about your cash cow.