Can we control tail biting in pigs without tail docking?
The animal Article of the Month for September is entitled Injurious tail biting in pigs: how can it be controlled in existing systems without tail docking?
Tail biting in growing pigs is a serious welfare problem because it is painful and may lead to infections for its victims. It also leads to economic losses to farmer. These are good reasons for trying to find ways to prevent and control tail biting.
Tail biting occurs in sporadic outbreaks, and can spread from pig to pig and pen to pen like an infectious disease. The sporadic nature of outbreaks makes it a challenging area of study. This was the impetus for researchers from SRUC, University of Copenhagen, and the Danish Pig Research Centre to collaborate on a critical review of the literature aimed at finding ways to control tail biting.
Of course, tail docking can be used to reduce the risk of tail biting but this raises ethical concerns: docking is painful and masks the symptoms rather than providing a cure. In the EU, routine tail docking has been banned since January 2003 (Council Directive 2001/93/EC), but is still a common practice in most member states.
Our review article in the September edition of animal presents many risk factors thought to affect tail biting, but often there is a lack of evidence on the size of the risk and on how it interacts with other risk factors. The risk factors best supported by evidence in our review were insufficient feeder space and a lack of suitable manipulable substrates such as straw.
The effects of farming systems in Countries (Finland, Norway, Switzerland) and certain schemes (Freedom Food, Organic, etc.) in which tail docking is not allowed, and where pigs are typically provided with straw or other forms of enrichment and extra space, were considered. However, even in these systems, tail biting appears to be worse than for tail docked pigs in conventional systems.
We reviewed the effectiveness of different types of enrichment and concluded that even quite small amounts of straw can reduce tail damage markedly. However, further research is needed to identify whether tail damage can be reduced by other materials such as ropes and wood, which do not block existing systems based on slatted floors with liquid slurry-handling systems. In the longer term, genetic approaches are promising, since tail biting differs between breeds and is heritable; also the use of ‘social breeding values’ has potential.
Some recent research suggests that early signs of tail biting can be detected before tail injuries are seen. It might be possible to intervene to prevent a damaging outbreak, particularly if detection could be automated somehow.
So tail biting can to some extent be prevented by means of better housing, husbandry and genetics. However, right now it cannot be fully prevented; and there is need to further develop ways of controlling it when it occurs.
Authors: R. B. D’Eath, G. Arnott, S. P. Turner, T. Jensen, H. P. Lahrmann, M. E. Busch, J. K. Niemi, A. B. Lawrence and P. Sandøe