Table & Row Selection

Table & Row Selection

Hoping this is a simple one.
 
I need to make the backgrounds on certain rows a different color to help the info to read better.
 
I used the following:
<!-- Directory of Staff Row Backgrounds -->
 <script type="text/javascript">
  $(document).ready(function() {
    $('tr:odd').addClass('odd');
  });
 </script>




 
But instead of starting over with a new table it seems to just have counted them all so it looks off. I'm newer to jQuery but hoping someone can hlep me shed some light on how to fix.
 
here is the page:
 
Thanks for any help!