your scores are great, for bio and OC they are average but acceptable by most schools, like they said in the previous post, if you are planing to apply for very competitive school then you need to raise those two scores, otherwise what i would do is to talk to the admissions office, or write a letter of intent stating that you are willing to retake the DAT if they request a repeat... but your grades are good, even if you plan to retake, i wouldn't worry too much, maybe spend one month strict on sciences and you will score off the chart. if you are worried whether you will get those high scores again on some of the subjects, SOME schools will still consider previous DAT scores as long as you score 18 or higher on the retake.