Here are some YT threads about yogurt. One thing that jumped out at me in them is that you must avoid artificial sweeteners...I would not give them anyway, but thought I should mention it.
If you do a search for yogurt on YT you will see many more threads on the topic!
http://www.yorkietalk.com/forums/yorkie-health-diet/161611-quick-yogurt-question.html
http://www.yorkietalk.com/forums/yor...-question.html
http://www.yorkietalk.com/forums/yor...85-yogurt.html