Docking is a routine method of care for lambs in Britain, and is undertaken primarily to prevent a blowfly strike, says Adam Henson.
Blowfly strike is a parasitic infestation, usually caused by the greenbottle fly being attracted to dung on the animals' behind.
When sheep graze on rich pastures their dung becomes loose and faecal matter (or dags) can accumulate on the tail and hindquarters.
In the summer months this attracts greenbottle flies that lay their eggs in the dags, which in turn hatch into maggots. The maggots burrow through the wool and into the living tissue of the animal. This causes pain and distress and can be fatal if left untreated.
How and when are lambs tails docked?
There are various methods of tail docking, but the most common way is to use a rubber ring (band) that must be applied to the lamb's tail before it is a week old. The band cuts off the blood supply and the long woolly tail drops off; otherwise it can be surgically removed.
Farmers consider carefully whether tail docking within a particular flock is necessary. Current legislation permits docking only if a sufficient length of tail is retained, but there are geographical differences in tail docking practices.
A review of the effectiveness of different docking strategies in combating blowfly strike concluded that docking the tail to medium length was most effective.
The British Veterinary Association recommends: "For many flocks, we recognise that tail-docking is currently the only practical means of managing the serious negative health and welfare outcomes of fly-strike. However, docking should be considered a last resort approach and should always be in consultation with a veterinary surgeon.
"Tail docking using a rubber ring or other device to constrict the flow of blood to the tail on animals aged not more than seven days. When any other method is used an anaesthetic must be administered. In all cases, enough of the tail must be retained to cover the vulva of a female animal or the anus of a male animal."
