It's not a formal sentence or a polite sentence. 鸟means bird in Chinese, but it has a similar meaning like dick. When you say 有个鸟用, it implies some emotion like scorn or dissatisfaction. You can also say 有个卵(egg)用 or something more unpleasant.Just like adding fucking in English. Avoid using these kind of sentence unless you are very familiar with the person. It may offend somebody.