Docking the tail of dogs has become a controversial topic, though the practice is quite old; indeed, there are even engravings and drawings going back to Assyrian times showing dogs with both docked tails and ears. The original reasons for docking a dog's tail are varied, but most involved trying to avoid the dog's pain while he was working. For example, dogs who spent a great deal of time working in fields could inadvertently pick up things like foxtails and burrs on their tails; these items would cause a great deal amount of pain, possibly distracting the dog from working efficiently. The injuries inflicted by foxtails and burrs were also at a risk for infection, which could lead to health risks in the dog, decreasing his ability to work. Breeds with long coats could become soiled with feces and/or urine and this could lead to insects and infection, again affecting a dog's potential to work.
These were not the only reasons why dogs had their tails docked. Indeed, the Old English Sheepdog did not have his tail docked to prevent injuries of the nature mentioned above. The Old English Sheepdog was a very important part of a shepherd's wealth, as he would not be able to herd his sheep or defend them from predators without this strong, brave, and loyal worker. Old English Sheepdogs also became vital in driving a farmer's sheep flocks and cattle herds to market, so that the shepherd could earn a living. If the sheep or cattle ran away, the shepherd would suffer serious economical loss. These dogs were truly essential to the welfare of the shepherds and farmers of the 1800s.
Unfortunately for the poorer citizens, English law (the Old English Sheepdog originated in England, hence the name) had established a dog tax, demanding that people pay a certain amount of money every year for each dog they had. Many experts believe that this was aimed at both increasing the monetary wealth of the upper class and further distinguishing the upper class from the lower classes; the upper class could own dogs because they could afford dogs. Thankfully, though, the lower classes were cut some breaks and some dogs were actually exempt from the tax; these were the working dogs, which included the herding dogs. In order for herding dogs to be easily identified, their tails were docked; actually, these dogs had their tails docked, or "bobbed", at or below the first joint, in contrast to other docked dogs who retained more of their tails.
Another reason why farmers and shepherds docked the Old English Sheepdog's tail was based on the belief that a dog's tail gave him balance and acted as a rudder. Farmers did not want their herding dogs to run off in chase of some wild animal or to run down one of their own flock; they wanted a dog that was a bit less agile, so that it would move the flock slowly. These docking practices were not only applied to the Old English Sheepdog; by the 19th century, all herding dogs were called "Bobtails" because they all had their tails bobbed. The name stuck for the Old English Sheepdog and to this day, he is still called "Bobtail".