。。
You actually call a tick 'Mr. Tick'? You're a funny kid.
Literal
Tick [to-に] 'san'-attach do [question-のか]. Funny kid [copula-だな].
さんづけ 'attaching ~さん' is a set noun for the practice of adding the polite honorific suffix ~さん to a name. Attaching it to a tick (ダニ, a nasty creature) is comically out-of-register — the humor is entirely in the register clash. コ (katakana 子) 'kid' is an affectionate form for 'person / child,' with the katakana rendering giving a slightly cool/stylized feel. だな combines the copula with the masculine reflective な.