Is it good to give probiotics (in drops form or powder form) to babies around 6 months for daily/weekly maintenance of a healthy gut? Any particular brands that is good and suitable ?

I read that fermented foods and drinks are great ways to introduce probiotics to babies naturally. Apparently, Russians give their babies milk kefir diluted with water when they are as young as 4 months old. You can start introducing baby to the sour taste of fermented foods by putting a little cultured vegetable juice on your finger and letting them suck on it. Cultured vegetables contain "Lactobacillus plantarum", a strain of friendly bacteria that is great in the treatment of colic, as well as crucial to the development of a healthy gut. http://bodyecology.com/articles/introduce_babies_probiotics.php