SAPARO-Info package: Tail biting

The aim of the SAPARO project (2020-2022) is to advance the welfare of pigs and producers.

The project has developed the SAPARO application, which is a free, web-based tool for pig farms to prevent and monitor tail biting. The application was developed for the producers’ needs by interviewing 15 pig farm managers, as well as by gathering comments on their user experience of the application and by

collecting information on the farms through on site visits. 

You can find the SAPARO application at 

On this website you will find information about tail biting and its risk factors, as well as printable material intended to pig farms on tail biting management planning. 


Contact information:

Professor Anna Valros,

Doctoral researcher Hilkka Koskikallio,

The app was developed with Ministry of Agriculture and Forestry of Finland funding.

Saparo project and tail biting

What is a tail biting? 

Tail biting is an abnormal behaviour that occurs when pigs are stressed. Tail biting pigs bite other pigs´ tails and cause varying degrees of injury. At its mildest, the lesion may be a single bite. At worst several pigs in the pen will lose their tail. As a result of the biting, the risk for secondary inflammations increases, which impairs the welfare of the pigs, increases the number of rejections at the slaughterhouse and causes additional work and costs for the farms. 

Risk Factors for Tail Biting 

Tail biting risk factors include deficiencies in the pigs’ living conditions, diet or state of health. To ensure their well-being, pigs should have the possibility to perform species-specific behaviour, such as rooting. In SAPARO, you can assess the risk factors for tail biting on your farm. The risk factor survey includes seven important areas for tail biting prevention. Below you will find the risk factor survey in pdf format.



Project leader, Professor Anna Valros, PhD, University of Helsinki 

Valros, who is an expert in pig tail biting leads the project. She is professor of animal welfare at the Faculty of Veterinary Medicine (University of Helsinki). 

Doctoral researcher Hilkka Koskikallio, M.Sc. (Agric.) 

Koskikallio is the main researcher of the project and is doing her PhD-dissertation on the topic. 

Professor Mari Heinonen, DVM, University of Helsinki

Heinonen is a professor specializing on swine diseases and health care at the Faculty of Veterinary Medicine (HY). In the project, she acts as expert especially in the field of pig health and disease protection. 

Postdoctoral Researcher Tiina Kauppinen, PhD, University of Helsinki 

Kauppinen has a PhD in welfare of farm animals, and she is an expert in human attitudes and behaviour change in the project. 

Assistant Professor Annukka Vainio, D.Soc.Sc., University of Helsinki 

Vainio is an assistant professor of sustainable behaviour change at the Institute of Sustainability Science of the University of Helsinki (HELSUS) and the Faculty of Agriculture and Forestry. She works as an expert in social psychology on the project. 

In cooperation: 

Animal Health ETT  

Suomen Sikayrittäjät ry. (Finnish Pig Entrepreneurs’ Association) 

Tail biting - Material bank

Printable Material for Pig Farms 

The website contains material for those working with pigs. The material can be utilised when planning risk factor management and treatment of tail biting as well and creating  effective practices in the fattening unit. 

Checklist for the risks of tail biting: what to consider when monitoring tail biting? 

Checklist for the risks of tail biting

Medication guidelines to be completed with the farm veterinarian: when and how are pigs medicated? 

Medication guideline template

Code of practice to prevent tail biting. How does your farm work to prevent tail biting? Fill in your own farm information. Alternatively, you can use a pre-filled sample template. 

Tail biting prevention and management template

Code of practice, management of acute tail biting. How does your farm react when tail biting occurs. Fill in your own farm information. Alternatively, you can use a pre-filled sample template. 

Tail biting management template

Calmness is important when handling pigs - a short guide to handling and moving pigs 

Handling of pigs

Learn more about tail biting

Inventory for tail biting risk assessment and pig observations:

Tail biting prevention tool developed in the UK: 

European Food Safety Authority publications on tail biting: 

Finnish Animal Welfare Centre EHK - information on tail biting: 

EU, reduction of tail docking: 

Tail biting studies by subject area

Health and welfare 

Boyle, L., A., Edwards, S., A., Bolhuis, J.,E., Pol, F., Šemrov, M., Z., Schütze, S., Nordgreen, J., Bozakova, N., Sossidou, E., N. & Valros, A. (2022). The Evidence for a Causal Link Between Disease and Damaging Behavior in Pigs. Front. Vet. Sci. 8:771682. - h7

Bracke, M., Edwards, S., Geers, R., O´Connell, N., Pedersen, L. J., & Valros, A. (2011). Subreport E: The risk associated with tail biting in pigs and possible means to reduce the need for tail docking. In: H. Spoolder, M. Bracke, C. Mueller-Graf, & S. Edwards (eds.), Technical report submitted to EFSA : Preparatory work for the future development of animal based measures for assessing the welfare of pigs: Report 2: Preparatory work for the future development of animal based measures for assessing the welfare of weaned, growing and fattening pigs including aspects related to space allowance, floor types, tail biting and need for tail docking (pages 84-106). EFSA European Food Safety Authority.

EFSA AHAW Panel (EFSA Panel on Animal Health and Welfare). (2014). Scientific Opinion concerning a multifactorial approach on the use of animal and non-animal-based measures to assess the welfare of pigs. EFSA Journal 2014;12(5):3702, 1-101.

Heinonen, M., Orro, T., Kokkonen, T., Munsterhjelm, C. M., Peltoniemi, O., & Valros, A. (2010). Tail biting induces a strong acute phase response and tail-end inflammation in finishing pigs. Veterinary Journal184(3), 303-307.

Heinonen, M., Välimäki, E., Laakkonen, A-M., Toppari, I., Vugts, J., Fabrega, E., & Valros, A. (2021). Evaluation of Tail Lesions of Finishing Pigs at the Slaughterhouse: Associations With Herd-Level Observations. Frontiers in Veterinary Science8, [650590].

Larsen, M. L., Gustafsson, A., Marchant-Forde, J. N., & Valros, A. (2019). Tear staining in finisher pigs and its relation to age, growth, sex and potential pen level stressors. Animal13(8), 1704-1711.

Munsterhjelm, C., Heinonen, M., & Valros, A. (2015). Effects of clinical lameness and tail biting lesions on voluntary feed intake in growing pigs. Livestock Science181, 210-219.

Munsterhjelm, C., Nordgreen, J., Aae, F., Heinonen, M., Olstad, K., Aasmundstad, T., Janczak, A. M., & Valros, A. (2017). To be blamed or pitied? The effect of illness on social behavior, cytokine levels and feed intake in undocked boars. Physiology & Behavior179, 298-307.

Munsterhjelm, C. M., Nordgreen, J., Aae, F., Heinonen, M. L., Valros, A. E., & Janczak, A. M. (2019). Sick and grumpy: changes in social behaviour after a controlled immune stimulation in group-housed gilts. Physiology & Behavior198, 76-83.

Munsterhjelm, C., Simola, O., Keeling, L., Valros, A., & Heinonen, M. (2013). Health parameters in tail biters and bitten pigs in a case-control study. Animal7(5), 814-821.

Nordgreen, J., Edwards, S., A. and Boyle, L., A., Bolhuis, E., Veit, C., Sayyari, A., Marin,D., E.,  Dimitrov, I., Janczak, A., M. and Valros, A. 2020. A proposed role for pro-inflammatory cytokines in damaging behaviour in pigs. Frontiers in Vet Sci 7:64.

Palander, P. A., Heinonen, M., Simpura, I., Edwards, S. A., & Valros, A. E. (2013). Jejunal morphology and blood metabolites in tail biting, victim and control pigs. Animal7(9), 1523-1531.

Telkänranta, H., Matchant-Forde, J. N., & Valros, A. (2016). Tear staining in pigs: a potential tool for welfare assessment on commercial farms. Animal10(2), 318-325.

Valros, A., & Heinonen, M. (2015). Save the pig tail. Porcine Health Management1(2), 1-7.

Valros, A., Munsterhjelm, C. M., Puolanne, E., Ruusunen, M., Heinonen, M., Peltoniemi, O. A. T., & Pösö, A. R. (2013). Physiological indicators of stress and meat and carcass characteristics in tail bitten slaughter pigs. Acta Veterinaria Scandinavica55, [75].

Valros, A., Palander, P., Heinonen, M., Munsterhjelm, C., Brunberg, E., Keeling, L., & Piepponen, P. (2015). Evidence for a link between tail biting and central monoamine metabolism in pigs (Sus scrofa domestica). Physiology & Behavior143, 151-157.

Valros, A., Välimäki, E., Nordgren, H., Vugts, J., Fabrega, E., & Heinonen, M. (2020). Intact Tails as a Welfare Indicator in Finishing Pigs? Scoring of Tail Lesions and Defining Intact Tails in Undocked Pigs at the Abattoir. Frontiers in Veterinary Science7, [405].

Veit, C., Janczak, A. M., Ranheim, B., Vas, J., Valros, A., Sandercock, D. A., Piepponen, P., Dulgheriu, D., & Nordgreen, J. (2021). The Effect of LPS and Ketoprofen on Cytokines, Brain Monoamines, and Social Behavior in Group-Housed Pigs. Frontiers in Veterinary Science7, [617634].

Viitasaari, E., Raekallio, M., Valros, A. et al. The effect of ketoprofen on feeding behavior of tail-bitten pigs. Porc Health Manag 1, 11 (2015).


Environment and risk factors 

Kallio, P. A., Janczak, A. M., Valros, A. E., Edwards, S. A., & Heinonen, M. (2018). Case control study on environmental, nutritional and management-based risk factors for tail-biting in long-tailed pigs. Animal Welfare27(1), 21-34.

Munsterhjelm, C., Heinonen, M., & Valros, A. (2015). Application of the Welfare Quality® animal welfare assessment system in Finnish pig production, part II: Associations between animal-based and environmental measures of welfare. Animal Welfare24(2), 161-172.

Munsterhjelm, C., Peltoniemi, O., Heinonen, M., Hälli, O., Karhapää, M., & Valros, A. (2009). Experience of moderate bedding affects behaviour of growing pigs. Applied Animal Behaviour Science118(1/2), 42-53.

Valros, A., & Barber, C. (2019). Producer Perceptions of the Prevention of Tail Biting on UK Farms: Association to Bedding Use and Tail Removal Proportion. Animals9(9), [628].

Valros, A. (2021). Review: The tale of the Finnish pig tail – how to manage non-docked pigs? Animal, 100353.



Telkänranta, H., Bracke, M., & Valros, A. E. (2014). Fresh wood reduces tail and ear biting and increases exploratory behaviour in finishing pigs. Applied Animal Behaviour Science161, 51-59.

Telkänranta, H., Swan, K., Hirvonen, H., & Valros, A. (2014). Chewable materials before weaning reduce tail biting in growing pigs. Applied Animal Behaviour Science157, 14-22.

Telkanranta, H., & Valros, A. (2020). Pigs with but not without access to pieces of recently harvested wood show reduced pen-mate manipulation after provision of feed and straw. Applied Animal Behaviour Science232, [105103].



Boyle, L., A., Edwards, S., A., Bolhuis, J.,E., Pol, F., Šemrov, M., Z., Schütze, S., Nordgreen, J., Bozakova, N., Sossidou, E., N. & Valros, A. (2022). The Evidence for a Causal Link Between Disease and Damaging Behavior in Pigs. Front. Vet. Sci. 8:771682. - h7

Munsterhjelm, C., Brunberg, E., Heinonen, M., Keeling, L., & Valros, A. (2013). Stress measures in tail biters and bitten pigs in a matched case-control study. Animal Welfare22(3), 331-338.

Munsterhjelm, C., Heinonen, M., & Valros, A. (2016). Can tail-in-mouth behaviour in weaned piglets be predicted by behaviour and performance? Applied Animal Behaviour Science184, 16-24..

Prunier, A., Valros, A., Tallet, C., & Turner, S. (2020). Consequences of the lactational environment on behavioural problems of pigs after weaning. In C. Farmer (Ed.), The suckling and weaned piglet (pp. 207-224). Wageningen Academic Publishers.

Valros, A., Ahlström, S., Rintala, H., Häkkinen, T., & Saloniemi, H. (2004). The prevalence of tail damage in slaughter pigs in Finland and associations to carcass condemnations. Acta agriculturae Scandinavica, (54), 213-219.

Valros, A., Sali, V., Hälli, O., Saari, S., & Heinonen, M. (2021). Does weight matter? Exploring links between birth weight, growth and pig-directed manipulative behaviour in growing-finishing pigs. Applied Animal Behaviour Science245, [105506].

Veit, C., Foister, S., Valros, A., Munsterhjelm, C., Sandercock, D. A., Janczak, A. M., Ranheim, B., & Nordgreen, J. (2021). The use of social network analysis to describe the effect of immune activation on group dynamics in pigs. Animal15(9), [100332].


Economy and production capacity 

Niemi, J., K., Edwards, S., A., Papanastasiou, D., K., Piette, D., Stygar, A., Wallenbeck,A. & Valros, A. (2021). Bio-Economic Modelling Analysis of Costs and Benefits of Seven Measures to Reduce Tail Biting Lesions in Fattening Pigs. Frontiers in Vet Sci . 8:682330.

Sinisalo, A., Niemi, J. K., Heinonen, M., & Valros, A. (2012). Tail biting and production performance in fattening pigs. Livestock Science143(2-3), 220-225.

Book chapters on tail biting

Valros, A. E. (2018). Tail biting. In M. Spinka (Ed.), Advances in Pig Welfare (pp. 137-166). (Advances in Farm Animal Welfare). Woodhead publishing.

Edwards, S. & Valros, A. (2021). Understanding and preventing tail biting in pigs. In S. Edwards (Ed.), Understanding the behaviour and improving the welfare of pigs, Burleigh Dodds Science Publishing, Cambridge, UK (ISBN: 978 1 78676 443 0)

Valros, A. (2020). Tail biting. In: I. Camerlink (Ed.). Pigs: Welfare in Practice. Sheffield: 5m Publishing.