Tail docking of dairy cows is prevalent in some regions. Some anecdotal reports have suggested that such docking may reduce SCC (somatic cell counts in milk) and occurrence of mastitis. However, a study examining such issues found no significant effect of docking on SCC or mastitis frequency or on four measures of cow cleanliness. Although it has been suggested that leptospirosis among dairy farm workers might be reduced by docking cows' tails, a study found that milkers' leptospiral titers were not related to tail docking. The American Veterinary Medical Association opposes "routine tail docking of cattle." Similarly, the Canadian Veterinary Medical Association opposes docking tails of dairy cattle.