Last year a friend and I moved some plastic barrel hives, otherwise known as “cows” into standard Langstroth hives. The cows were impossible to inspect having gone cross-combed almost from the start. Additionally, they could not be assessed for Varroa nor treated. The history was that originally there had been ten but, through attrition, in about a year they were down to two remaining. The move was successful and the colonies flourished through the remainder of the year.