* Jensen, M.B., Herskin, M, Forkman, B, Pedersen, L.J., 2015. Effect of increasing amounts of straw on pigs’ explorative behaviour. Applied Animal Behaviour Science 171, 58–63.
* Carr, R.W., J.E. Coe, E. Forsch, M. Schmelz, D.A. Sandercock, 2015. Structural and functional characterisation of peripheral axons in the caudal nerve of the neonatal pigs: Preliminary data. Proceedings of the 9th EFIC Congress, Vienna, Sept 2-5. (Abstract & poster)
* Di Gininiani P, Stausholm JS, Viitasaari E, Petersen LJ, Herskin MS 2015. Description of mechanical nociceptive testing on hind legs and tails of pigs. Abstract 1054, Proceedings of the 9th EFIC Congress, Vienna, Sept 2-5. Poster
* Anon. 2015. Varkensstaartje in Finland niet gecoupeerd. [Small pig tail not docked in Finland]. V-focus April 2015, p. 17.
* Bracke, M., Aarnink, A., Vermeer, H. en Rotgers, G. 2014. Extra snijmais goed voor welzijn varkens. [Additional maize silage good for pig welfare] V-focus, december 2014, p. 34-35.
* Zonderland, J. 2013. Tail biting in pigs – Guidance for New Zealand pig producers. New Zealand Pork.
* Kauppinen, T. 2015. The pig tail, even when bitten, is an indicator of pig welfare. Elä, accessed 17-2-2015.
* Edman, F. 2014. Do the Member States of the European Union comply with the legal requirements for pigs regarding manipulable material and tail docking? Student report 572, SLU, Skara, Sweden. Accessed 17-2-2015.
* Marzocchi, O. 2014.  Routine tail-docking of pigs. Policy Department C: Citizens’ Rights and Constitutional Affairs, European Parliament, European Union, Brussels, accessed 17-2-2015.
* Biørnstad, L., 2014. Vil forhindre at griser biter hverandre i halen – Om grisene ikke har det bra kan de begynne å bite hverandre i halen. Det gir syke griser og tapte inntekter. [To prevent tail biting in pigs – About pigs not doing well , they may begin to bite each other’s tail, resulting in sick pigs and lost revenue.] (Interview with Andrew Janczak, incl. video).
* Pedersen, Lene J., Mette S. Herskin, Björn Forkman, Ulrich Halekoh, Kristian M. Kristensen, Margit B. Jensen, 2014. How much is enough? The amount of straw necessary to satisfy pigs’ need to perform exploratory behaviour. Appl. Anim. Behav. Sci. 160, 46–55.
* Valros, A., (2014). “Save the pig tale”. Presentation at the 2014 ESPHM congress in Sorrento, Italy 7-9.5
* Westin, R. 2014. Strategic Use of Straw at Farrowing – Effects on Behaviour, Health and Production in Sows and Piglets. PhD thesis, SLU, Skara.
* The EUWelNet project has developed an elearning tool on tail biting.
* Telkänranta H., Bracke M.B.M., Valros A. 2014. Reducing oral-nasal manipulation on commercially farmed pigs: fresh wood enhances the efficacy of straw. In: Lišková S & Varadínová Z (eds): VII European Conference on Behavioural Biology, Book of Abstracts, p. 221.
* Telkänranta H., Bracke M.B.M., Valros A. 2014. Fresh wood, plastic pipe or metal chain – which objects reduce tail and ear biting on commercial pig farms? In: Estevez I, Manteca X, Marin TH, Averós X (eds): Proceedings of the 48th Congress of the International Society for Applied Ethology, p. 282.
* Bracke, M.B.M., Ettema K. 2014. Pigs suffering from injurious behaviours like flank biting and tail biting are more interested to manipulate a novel rope than uninjured control animals. Proceedings of Measuring Behavior 2014, (Wageningen, The Netherlands, August 27-29, 2014). Editors: A.J. Spink, L.W.S. Loijens, M. Woloszynowska-Fraser & L.P.J.J. Noldus.
* Ursinus, W.W., Van Reenen, C.G., Reimert, I., Bolhuis, J.E., 2014. Tail Biting in Pigs: Blood Serotonin and Fearfulness as Pieces of the Puzzle? PlosOne 9: 1-14.
* D’Eath, R. B., G. Arnott, S. P. Turner, T. Jensen, H. P. Lahrmann, M. E. Busch, J. K. Niemi, A. B. Lawrence and P. Sandøe, 2014. Injurious tail biting in pigs: how can it be controlled in existing systems without tail docking? Animal 8: 1479-1497.
* Spoolder, H, Bracke, M., Rotgers, G. 2014. EFSA-advice for better welfare of pigs [in Dutch]. V-focus augustus 2014, 34-35.
* Van der Peet, G.F.V., 2014. Curly tails in pig production – Motto, Yes We Can!” [In Dutch].
* Ursinus, W. 2014. A tale too long for a tail too short?” PhD. Wageningen University.
* Herskin, M.S., Di Giminiani, P., Sandercock, D., Prunier, A., Talet, C., Leach, M., Edwards, S., 2014. Can peripheral nerve damage caused by tail docking lead to tail pain later in the life of pigs. Estevez, I., Manteca, X., Marin R.H. and Averos, X. (Eds): Proceedings of the 48th congress of the International Society for Applied Ethology, Spain, p. 135.
* EFSA (2014). Scientific Opinion concerning a multifactorial approach on the use of animal and non-animal-based measures to assess the welfare of pigs. The EFSA Journal 12: 3702 (with contributions from partners in the FareWellDock project).
* Sandercock, D. (2014). Mutilation procedures: welfare implications and new strategies – Better Training for Safer Food Initiative, Training course on “Animal Welfare in pig production”, Herning, Denmark, 12-15 May, 2014
* Factsheet ‘Tail biting in pigs‘, Farm Animal Education Centre, February 2014, The Farm Animal Welfare Fact Sheet No. 8.
* EU pig sector behaves as if it’s above the law – Initiative of Compassion in World Farming to emphasise the need for better enrichment and less tail docking in the EU, d.d. 28-10-2013).
* European Commission to issue guidelines on the welfare of pigs Animal Health and Welfare (25-03-2013)
* – Dutch website on enrichment materials and tail biting in pigs.
* Research results on pig enrichment – The research project “New innovations for environmental enrichment on pig farms” of the University of Helsinki.
* Enrichement materials for the outdoor run of organic pigs (Biovak 2011). Flyer with examples of enrichment (in Dutch)
Risks associated with tail biting and means to reduce tail docking (EFSA report, 2007) This report provides a detailed overview of scientific research on tail biting, tail docking and enrichment (up until 2007). Pages 93 and 95 shows figures of the relative risks for tail biting in the EU for docked and undocked pigs.
* Update EFSA report on enrichment materials (p.27-30) and tail biting (p. 85 ff) (Spoolder et al., 2011).
* Decision support system to assess the risk for tail biting (PIGTAIL model) (Bracke et al., 2004). The table on page 35 shows a list of 28 risk factors and their relative importance (weighting factors).
* Pig Husbandry Advisory Tool (WebHAT) (Taylor et al., 2009), provides support to assess risk factors for tail biting and design strategies to solve the problem (UK research project).
Talking Tails (Zonderland, 2010). Dissertation on the development of tail biting in groups of weaned pigs: providing a handful of straw per pig per day prevents tail biting, and tail posture can help in the early detection of a tail biting outbreak.
* Bracke et al. (2012). Attitudes of Dutch Pig Farmers Towards Tail Biting and Tail Docking
* Prunier et al. (2005). Effects of castration, tooth resection, or tail docking on plasma metabolites and stress hormones in young pigs
* Schrøder-Petersen and Simonsen (2001) Tail biting in pigs
* Van de Weerd et al. (2005). The development of harmful social behaviour in pigs with intact tails and different enrichment backgrounds in two housing systems
* Van de Weerd et al. (2003). A systematic approach towards developing environmental enrichment for pigs
* Zwicker et al. (2013) Short-and long-term effects of eight enrichment materials on the behaviour of finishing pigs fed ad libitum or restrictively
* Scollo et al. (2013) Tail docking and the rearing of heavy pigs: The role played by gender and the presence of straw in the control of tail biting. Blood parameters, behaviour and skin …
* Jensen et al. (2008). Pigs’ preferences for rooting materials measured in a three-choice maze-test
* Pedersen et al. (2005). The strength of pigs’ preferences for different rooting materials measured using concurrent schedules of reinforcement
* Van de Weerd et al. (2006). Effects of species-relevant environmental enrichment on the behaviour and productivity of finishing pigs
* Van de Weerd et al. (2009). A review of environmental enrichment for pigs housed in intensive housing systems
* Bracke and Spoolder (2008). Novel object test can detect marginal differences in environmental enrichment in pigs
* Studnitz et al. (2007). Why do pigs root and in what will they root?: a review on the exploratory behaviour of pigs in relation to environmental enrichment
* Jensen and Pedersen (2007). The value assigned to six different rooting materials by growing pigs
* Fraser (1987). Mineral-deficient diets and the pig’s attraction to blood: implications for tail-biting
* Lonardi, C., Leach, M., Gottardo, F., Edwards, S. 2013. The ‘Grimace Scale’: do piglets in pain change their facial expression? Proceedings of the Joint Meeting of the 5th European Symposium of Porcine Health Management and the 50th Anniversary Meeting of the Pig Veterinary Society of Great Britain, Edinburgh, UK, 22nd – 24th May 2013.
* Palander et al. (2013). Jejunal morphology and blood metabolites in tail biting, victim and control pigs
* Zonderland et al. (2011). Individual piglets’ contribution to the development of tail biting
* Brunberg et al. (2012). Brain gene expression differences are associated with abnormal tail biting behavior in pigs.
* Zonderland et al. (2011) Characteristics of biter and victim piglets apparent before a tail-biting outbreak
* Telkänranta, H. Research results on pig enrichment – The research project “New innovations for environmental enrichment on pig farms (in English, Swedish and Finnish). University of Helsinki, Faculty of Veterinary Medicine

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Norwegian University of Life Sciences


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University of Helsinky

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