I used goats milk kefir which is similar to a yogurt but typically with a higher probiotic content. (fairygutmother.com)
This is due to the Vitamin D, antibody, and probiotic content found in raw milk. (wellness-media.com)
Just be warned that consuming large amounts of any fermented foods may cause loose stools because of the natural probiotic content. (realfoodoutlaws.com)