Why are most EU pigs tail docked? Economic and ethical analysis of four pig housing and management scenarios in the light of EU legislation and animal welfare outcomes

Abstract

To limit tail biting incidence, most pig producers in Europe tail dock their piglets. This is despite EU Council Directive 2008/120/EC banning routine tail docking and allowing it only as a last resort. The paper aims to understand what it takes to fulfil the intentions of the Directive by examining economic results of four management and housing scenarios, and by discussing their consequences for animal welfare in the light of legal and ethical considerations. The four scenarios compared are: ‘Standard Docked’, a conventional housing scenario with tail docking meeting the recommendations for Danish production (0.7 m2/pig); ‘Standard Undocked’, which is the same as ‘Standard Docked’ but with no tail docking, ‘Efficient Undocked’ and ‘Enhanced Undocked’, which have increased solid floor area (0.9 and 1.0 m2/pig, respectively) provision of loose manipulable materials (100 and 200 g/straw per pig per day) and no tail docking. A decision tree model based on data from Danish and Finnish pig production suggests that Standard Docked provides the highest economic gross margin with the least tail biting. Given our assumptions, Enhanced Undocked is the least economic, although Efficient Undocked is better economically and both result in a lower incidence of tail biting than Standard Undocked but higher than Standard Docked. For a pig, being bitten is worse for welfare (repeated pain, risk of infections) than being docked, but to compare welfare consequences at a farm level means considering the number of affected pigs. Because of the high levels of biting in Standard Undocked, it has on average inferior welfare to Standard Docked, whereas the comparison of Standard Docked and Enhanced (or Efficient) Undocked is more difficult. In Enhanced (or Efficient) Undocked, more pigs than in Standard Docked suffer from being tail bitten, whereas all the pigs avoid the acute pain of docking endured by the pigs in Standard Docked. We illustrate and discuss this ethical balance using numbers derived from the above-mentioned data. We discuss our results in the light of the EU Directive and its adoption and enforcement by Member States. Widespread use of tail docking seems to be accepted, mainly because the alternative steps that producers are required to take before resorting to it are not specified in detail. By tail docking, producers are acting in their own best interests. We suggest that for the practice of tail docking to be terminated in a way that benefits animal welfare, changes in the way pigs are housed and managed may first be required.

Managing undocked pigs – on-farm prevention of tail biting and attitudes towards tail biting and docking

“…This might also be an explanatory factor for why Finland can manage so well with the non-docking policy: Finnish farms are, on average smaller than in many other EU countries. On large farms, often with a reduced caretaker/pig ratio, it becomes more difficult to spot tail biting early enough, and have time to intervene appropriately [10]. However, we did not find a correlation between farm size and occurrence of tail biting in this study.…”

“…Based on available studies, Valros & Heinonen [8] suggested that tail docking reduces the prevalence of severe lesions by about 50 %. Tail docking in itself, in addition to causing acute, and possibly chronic pain [9], reduces the risk of tail biting when keeping pigs in rearing systems with a higher level of risk factors, and thus might increase the risk of keeping pigs in a way that is not optimal for their welfare [8, 10]. Another important reason for favouring long-tailed pigs is that in non-docked pigs, the status of the tails can be used as a measure of the overall welfare status on the farm [11].…”

“…Hunter et al [15] asked farmers in the UK about which intervention measures they mostly use and found that removal of the bitten pig or the biter, and adding objects for manipulation were the most commonly used measures. However, to our knowledge there is no comparable data from conventional farmers not docking their pigs, while a need for such information has been identified [10]. …”

Provision of straw by a foraging tower –effect on tail biting in weaners and fattening pigs

“…However, victims of tail biting suffer from acute pain, have an increased risk of infections and a reduced weight gain. As a consequence, tail biting is not compatible with welfare and it is in the interest of pig producers to avoid economical losses due to tail biting [1, 8]. Nevertheless, the prevention of tail biting should focus on identifying and eliminating predisposing, possibly interacting risk factors.…”

Molecular approaches to the diagnosis and monitoring of production diseases in pigs

“…Stress can be caused by overcrowding, frequent mixing of different litters, and too high a temperature. Tail biting, a common consequence of stress has been estimated to cost around 18 Euros per affected pig which includes medication, veterinary care and carcass condemnation (D'Eath et al, 2016).…”