All this information was important for the determination of the villous height /crypt depth ratio that may indicate the proper development of intestinal epithelia regulated by probiotics. Authors also deliberate on the villous surface area parameter that may contribute to the enhancement of the intestinal absorptive area which seems to be positively regulated by probiotics in a majority of the available evidence. From the perspective of the functionality of the GIT, particularly that which is affected by probiotics the most important being cell proliferation, migration and turnover regulated by apoptosis
