Tail biting and tail docking are major welfare concerns for pigs, particularly for those kept in barren intensive housing. Most piglets housed in these systems have their tails docked within days of birth to prevent tail biting later in life.
What is tail biting?
Tail biting is an abnormal behaviour whereby pigs use their teeth to bite and chew other pigs’ tails. Tail biting can lead to injuries in the victim, and the victim can experience pain and fear, which can be exacerbated in an outbreak where pigs performing the biting can target victims with persistency. Tail biting can also be associated with a variety of conditions including spinal abscesses, septicaemia, and a reduced growth rate. The behaviour can spread socially throughout a group of pigs quite rapidly and is therefore a significant welfare problem in commercial pig production.
What is tail docking?
Tail biting on commercial farms has led to the widespread adoption of tail docking. While it is a common management practice to prevent tail biting, it causes acute trauma and pain since the tail has lots of nerves. Tail docking causes piglets to struggle, squeal, and clamp their tails between their hind limbs and lower their head, indicating that it is highly painful. Further, pigs which have had their tails docked may experience long-term pain and be susceptible to infection.
Tail docking reduces the frequency of tail biting but does not completely eliminate it, and does not address the underlying causes.
In the European Union, tail docking on a routine basis has been prohibited, and there is further legislation limiting its use in countries including Denmark, Sweden, and Finland. In Australia, the Model Code of Practice for the Welfare of Animals: Pigs suggests that where tail docking is performed as a routine preventative measure, it should be carried out before pigs are seven days of age.
Methods to address tail biting and alternatives to tail docking
Although multifactorial, one of the main factors which contribute to the incidence of tail biting is a barren environment and the inability for pigs to perform exploration and foraging behaviour. In order to reduce the incidence of tail biting, pigs should be provided with an environment that offers appropriate stimulation and satisfies their motivation to explore and chew e.g. the provision of straw or other enrichment types. Good stockpersonship (positive handling) and a good pig-to-stockperson ratio (allowing close monitoring) are essential to abate tail biting to identify changes in pig behaviour early and allow time for intervention.
Hazards for tail biting behaviour include an absence of straw bedding and enrichment, high stocking density, inadequate or sudden changes in diet, competition for resources, poor health status, the season, air quality and speed, and stress. In addition to this, the heritability of tail biting has been found to be high enough for genetic selection against the behaviour. Genetic selection may therefore be a promising route to addressing tail biting, in addition to optimising the environment and management.
Since tail biting can cause very poor welfare and tail docking is painful both in the short and long term, measures other than tail docking should be implemented to control tail biting. Intact tails that are unbitten are probably the best indicator of a well-managed pig production system.
What is the RSPCA’s position on tail docking in pigs?
The RSPCA is opposed to the docking of the tails of any species of animal unless under veterinary advice to improve an individual animal’s health. Since tail docking is painful in the short and in the long term, measures other than tail docking should be implemented to control tail biting. Tail docking is not permitted under the RSPCA Approved Farming Scheme Standards – Pigs.
European Food Safety Authority (2007) Scientific Report on the risks associated with tail biting in pigs and possible means to reduce the need for tail docking considering the different housing and husbandry systems. The EFSA Journal 611:1-98.
Scollo A, Contiero B, Gottardo F (2016) Frequency of tail lesions and risk factors for tail biting in heavy pig production from weaning to 170 kg live weight. Veterinary Journal 207:92–98.
Sutherland MA, Bryer PJ, Krebs N and McGlone JJ (2009) The effect of method of tail docking on tail-biting behaviour and welfare of pigs. Animal Welfare 18:561-570.