A link between damaging behaviour in pigs, sanitary conditions, and dietary protein and amino acid supply
By Yvonne van der Meer, Walter J. J. Gerrits, Alfons J. M. Jansman, Bas Kemp, J. Elizabeth Bolhuis. PLOS, Published: May 8, 2017
The tendency to reduce crude protein (CP) levels in pig diets to increase protein efficiency may increase the occurrence of damaging behaviours such as ear and tail biting, particularly for pigs kept under suboptimal health conditions. We studied, in a 2×2×2 factorial design, 576 tail-docked growing-finishing entire male pigs in 64 pens, subjected to low (LSC) vs. high sanitary conditions (HSC), and fed a normal CP (NP) vs. a low CP diet (LP, 80% of NP) ad libitum, with a basal amino acid (AA) profile or supplemented AA profile with extra threonine, tryptophan and methionine. The HSC pigs were vaccinated in the first nine weeks of life and received antibiotics at arrival at experimental farm at ten weeks, after which they were kept in a disinfected part of the farm with a strict hygiene protocol. The LSC pigs were kept on the same farm in non-disinfected pens to which manure from another pig farm was introduced fortnightly. At 15, 18, and 24 weeks of age, prevalence of tail and ear damage and of tail and ear wounds was scored. At 20 and 23 weeks of age, frequencies of biting behaviour and aggression were scored for 10×10 min per pen per week. The prevalence of ear damage during the finisher phase (47 vs. 32% of pigs, P < 0.0001) and the frequency of ear biting (1.3 vs. 1.2 times per hour, P = 0.03) were increased in LSC compared with HSC pigs. This effect on ear biting was diet dependent, however, the supplemented AA profile reduced ear biting only in LSC pigs by 18% (SC × AA profile, P < 0.01). The prevalence of tail wounds was lower for pigs in LSC (13 ± 0.02) than for pigs in HSC (0.22 ± 0.03) in the grower phase (P < 0.007). Regardless of AA profile or sanitary status, LP pigs showed more ear biting (+20%, P < 0.05), tail biting (+25%, P < 0.10), belly nosing (+152%, P < 0.01), other oral manipulation directed at pen mates (+13%, P < 0.05), and aggression (+30%, P < 0.01) than NP pigs, with no effect on ear or tail damage. In conclusion, both low sanitary conditions and a reduction of dietary protein increase the occurrence of damaging behaviours in pigs and therefore may negatively impact pig welfare. Attention should be paid to the impact of dietary nutrient composition on pig behaviour and welfare, particularly when pigs are kept under suboptimal (sanitary) conditions.
Is it possible to get rid of tail docking? By Vincent ter Beek 2017. Article in PigProgress about FareWellDock.
Tail docking is a well-known practice in pig production, but it is also heavily criticised. An international team of researchers dived into the topic and wondered what its exact effects are on pigs – and what alternatives there are to avoid tail biting….
Note: This article is an approved summary of the Executive Summary which was published earlier this year at http://farewelldock.eu. In future issues of Pig Progress, to be published later this year, several participating researchers in this project will delve deeper into the individual topics they encountered.
Herskin, M.S. and P. Di Giminiani, 2017. Pigs in pain—causes, mechanisms, and possibilities for future development. Abstract from BEHAVIOR, HOUSING, AND WELL-BEING SYMPOSIUM: FINDING EFFECTIVE WAYS TO MANAGE PAIN IN LIVESTOCK, a conference of the American Society for Animal Science Midwestern Meeting, Omaha, NE, 13-15 March 2017
Despite a long history of debate about negative affective states in animals, it was only in the last decades of the 20th century that the state of pain was mentioned in definitions of animal welfare, included in veterinary education, and became a target of scientific interest. Pain is a perceptional phenomenon built from information gathered by specialized sensory receptors for tissue damage and integrated into a discrete experience with a negative emotional valence in the brain. Based on knowledge about porcine neuroanatomy, physiology, and studies focusing on pig behavior and pathology, we review evidence for causes of pain in pigs, underlying biological mechanisms, as well as the possibility to quantify different types of indicators of pain states relevant to the welfare of the animals under production conditions. The presentation will primarily focus on pigs because of the dual purpose of this species as a meat producing as well as research animal species (the latter driven by the anatomical and physiological homologies with humans), making pigs unique among livestock. We will present methodologies and results from current research projects across Europe and North America targeting typical industry-related injuries (e.g., tail docking, lameness, and shoulder lesions) and aiming to understand the welfare consequences for the pigs. Throughout the talk, the emphasis will be put on future opportunities to link research outcomes with industry initiatives toward the improvement of animal welfare and production. In addition, possible future research efforts to help face current methodological limitations and favor a more comprehensive evaluation of animal pain as an overall experience will be discussed. This seeks to facilitate common future targeted research and enable us to overcome the paradoxical low level of knowledge about porcine pain and its alleviation under production conditions.
Tail biting constitutes a major welfare and health issue in commercial pig rearing, with significant negative economic consequences. Contrary to the aim of the EU directive (2001/93/EC), tail docking is still widely practiced in most EU countries as a measure to reduce the incidence of tail biting and concomitant pathologies. Mutilations are a general welfare concern in all species, and any efforts towards reducing the need for tail docking are important for the future sustainability of the EU pig sector. Sound policy making needs science-based risk assessment, including assessment of the severity of problems and effectiveness of solutions. The general objectives of the FareWellDock-project included estimation of the relative harms associated with tail docking and tail biting, and evaluation of the efficacy of some main preventive measures against tail biting, which could reduce the need for tail docking. The ultimate aim was to stimulate the development towards a non-docking policy in the EU.
The first objective of WP1 was to evaluate measures of acute and chronic pain in relation to tail damage. This included assessment of the short (acute trauma), medium (post trauma inflammation) and long term (traumatic neuroma formation) pain associated with tail docking in neonatal piglets, and the possible consequences for longer term fear of humans. In addition, the studies assessed the effects of tail-damage in more mature pigs to provide a basis for assessing the pain associated with being tail bitten in later life. Finally, studies were conducted to assess the effects of an NSAID analgesic on the short term responses to neonatal tail docking.
Experimental studies confirmed that piglets do experience pain when tail docked, and that pain relief treatment, such as meloxicam, can lessen but not abolish the physiological stress reaction to docking. Piglets which have been tail docked seem more fearful of people afterwards than undocked animals. In docked tails, no difference in pain sensitivity of the tail (as measured by behavioural withdrawal) is detected after 8 weeks, but changes in the functioning of the sensory nerves from the tail can still be measured after 4 months, which suggests that the possibility for longer term pain exists. When the tail is damaged later in life, as happens with tail biting, changes in both tail stump sensitivity and nerve functioning can last for at least 4 months, and possibly beyond.
WP2 focused on the role of manipulable material when reducing the need for tail docking. The aim was to develop and validate ways to assess if on-farm use of manipulable material is sufficient to reduce tail biting. Further, the aim was to describe suitable methods for implementing the use of straw under commercial farming conditions and to investigate, in on-farm conditions, the efficiency of tail docking vs. enrichment given in sufficient quantity to reduce the occurrence of tail lesions.
A screening method to assess the appropriateness of the level of enrichment on-farm was developed and includes scoring of the amount of unsoiled straw, the behaviour, and ear, tail and flank lesions of the pigs. AMI (animal-material interaction) sensors were used e.g. to show that pigs in biter pens were more interested in novel ropes than pigs in control pens, that environmental enrichment may reduce exploratory behaviour of point-source objects, and that sick pigs, experimentally infected with streptococcus spp, were less interested in chain manipulation. The sensors appear to be a promising tool to assess the use of manipulable material by pigs. In countries (SE and FI) where tail docking is not done, farmers report using on average of 30 to 50 g of straw/pig/ day, equivalent to about 0.5 L/pig/day. A survey in SE revealed fewer injurious tail biting outbreaks on farms using larger amounts of straw. Larger amounts of straw were mainly used on farms having scrapers in the slurry channels. A large experimental study showed that a moderate amount of straw (150 gr/pig/day) reduced injurious tail-biting outbreak in finisher pigs by more than 50%, while docking seemed to be more effective as it reduced tail biting by more than four-fold. The effect of both measures was additive, i.e. docking and straw reduced tail biting 9 fold. Further, it was shown that increasing the amount of straw from 10 to up to 400 gr/pig/day had multiple positive effects by progressively reducing the occurrence of tail injuries and stomach ulcers, increasing growth rate, increasing straw-directed behaviour, and reducing redirected behaviours towards other pigs.
In WP3 the aim was to clarify the role of poor health in the causation of tail biting and victimization, and the aim was study early identification of tail-biting outbreaks. In addition, the aim to develop automated systems for early warning of tail biting outbreaks.
The results of experimental and on-farm studies showed that the social behaviour of sick pigs differs from healthy pen mates, as pigs with osteochondrosis received more sniffing and tail bites from their pen mates than healthy pigs, while pigs with mild respiratory disease tended to bite more at the ears and tails of pen mates than healthy pigs did. In addition, studies of cytokines suggest that low-grade inflammation may decrease activity and increase receiving sniffs and attacks from other pigs. Studies on data sets from commercial pig farms indicated that changes in feeding behaviour may be an important sign of an increased risk for tail biting to occur: Future tail bitten individuals showed a reduced feed intake already 2-3 weeks before tail damage became evident. Furthermore, feeding behaviour in groups which develop tail biting may differ from non-biting groups for at least ten weeks prior to an injurious tail-biting outbreak. It was also shown that tail-chewing activity may start 2-3 weeks before tail damage can be seen. A detailed behavioural study of tail biting events revealed that there appears to be no such thing as a ‘typical’ tail-biting event and that the behaviour shown immediately before a tail-biting event does not differ from behaviour prior to another type of social interaction, namely ano-genital sniffing. Thus, it seems difficult to predict if a social event will escalate into tail biting or not. However, tail biting is more likely between pigs that have previously interacted. Data sets from several countries and studies indicated an association between tail-biting damage and tear staining, but the direction of this association is not clear.
In summary the project concluded on a set of practical recommendations, which have been published as part of four factsheets on the FareWellDock-webpage:
- Avoid tail docking whenever possible because it definitely causes pain, induces long-term changes in sensory-nerve function and may impair the pigs’ confidence in humans.
- Avoid tail biting, and hence the need for tail docking, by addressing risk factors on the farm.
- Treat tail-bitten pigs promptly and consider pain relief.
- To reduce injurious tail-biting outbreaks, use straw as it might be almost as effective as tail docking. For this purpose, the more straw the better.
- To ensure that sufficient straw is allocated check that there is left-over straw before the next day’s allocation.
- Keep your pigs healthy. This will be good both for productivity and also help avoid injurious tail-biting outbreaks.
- If pigs show signs of illness, be more alert to tail biting risk.
- Remove tail-bitten pigs promptly to avoid further damage and treat according to veterinary advice.
- Pay special attention to groups of pigs where you see:
- high or suddenly increased levels of general activity or exploration
- tail manipulation or chewing
- swinging or tucked tails
- low or decreasing numbers of visits to an automatic feeder or reduced feed intake
Information on project activities and publications have been continuously published on the FareWellDock-webpage. To date, 16 scientific articles have been published, and 9 are in preparation. Communication to stakeholders has been active, both through the FareWellDock-webpage, including 97 blog posts, and by interviews in media in different countries, popular articles and presentations at producer seminars. In October 2016 the results were presented widely at the EU level to policy makers and other stakeholders at the ‘Meeting and Webinar on Actions to Prevent Tail biting and Reduce Tail docking of Pigs’, organized by the European Commission Directorate General for Health and Food Safety in Grange, Ireland.
Due to the positive experience of the cooperation a decision was made at the last project meeting in DK in October 2016 that we will continue our cooperation as the FareWellDock-network, also inviting further researchers and stakeholders to join. The first activity of the FWD-network will be to organise a satellite meeting at the Congress of the International Society for Applied Ethology in August 2017 in DK, and to launch an emailing list to make sure FWD-network members and other researchers keep updated on research progress and related topics.
The FareWellDock factsheets are out. Below you find the cover factsheet as well as the factsheets on tail docking, enrichment, health and the prediction of tail biting. This post shows images of the English versions, and links to the pdf version of the English factsheets, as well as all factsheets in Danish, Dutch, Finnish, French, Italian, Norwegian and Swedish. Separate pages are available directly showing the factsheets in the other languages (Danish, Dutch, Finnish, French, Italian, Norwegian and Swedish).
Factsheet cover English (pdf)
Factsheet cover Danish (pdf)
Factsheet cover Dutch (pdf)
Factsheet cover Finnish (pdf)
Factsheet cover French (pdf)
Factsheet cover Italian (pdf)
Factsheet cover Norwegian (pdf)
Factsheet cover Swedish (pdf)
Factsheet 1 Tail docking English (pdf)
Factsheet 1 Danish (pdf)
Factsheet 1 Dutch (pdf)
Factsheet 1 Finnish (pdf)
Factsheet 1 French (pdf)
Factsheet 1 Italian (pdf)
Factsheet 1 Norwegian
Factsheet 1 Swedish (pdf)
Factsheet 2 Enrichment English (pdf)
Factsheet 2 Danish (pdf)
Factsheet 2 Dutch (pdf)
Factsheet 2 Finnish (pdf)
Factsheet 2 French (pdf)
Factsheet 2 Italian (pdf)
Factsheet 2 Norwegian (pdf)
Factsheet 2 Swedish (pdf)
Factsheet 3 Health English (pdf)
Factsheet 3 Danish (pdf)
Factsheet 3 Dutch (pdf)
Factsheet 3 Finnish (pdf)
Factsheet 3 French (pdf)
Factsheet 3 Italian (pdf)
Factsheet 3 Norwegian (pdf)
Factsheet 3 Swedish (pdf)
Prediction of tail biting
Factsheet 4 Prediction English (pdf)
Factsheet 4 Danish (pdf)
Factsheet 4 Dutch (pdf)
Factsheet 4 Finnish (pdf)
Factsheet 4 French (pdf)
Factsheet 4 Italian (pdf)
Factsheet 4 Norwegian (pdf)
Factsheet 4 Swedish (pdf)
From beak to tail – mechanisms underlying damaging behaviour in laying hens and pigs
ISAE 2017 Satellite Meeting
Monday 7th August 2017,
University of Aarhus, Denmark
A one-day meeting, organized jointly by the FareWellDock – Network and the GroupHouseNet COST-action aims to bring together researchers working within the field of damaging behaviour in both pigs and poultry. By joining efforts on an interspecies level, we have the opportunity to greatly enhance the understanding of the mechanisms underlying tail biting and feather pecking. Both behaviours are challenging, from an animal welfare and from an economic point-of-view, while in several countries, as well as at the EU level, the ethical justification of tail docking and beak trimming is currently being debated.
This full-day meeting will be held at the ISAE 2017 congress venue on August 7th, 2017, starting at 9am.
The meeting will focus on the following main themes:
– Mechanisms underlying the link between health and damaging behaviour
– Predisposing factors for damaging behaviour during early development
Both themes will be introduced by invited experts, followed by short research presentations by participants, and then elaborated on in inter-species discussion groups.
In addition, the program will include a networking session, with the aim to facilitate knowledge exchange and future cooperation between researchers working on damaging behaviour in pigs and poultry.
The registration for the meeting will open by the end of February 2017, and will be open until May 15th, 2017. The meeting participation is limited to 80 persons, so make sure to register in time!
For further information, please contact anna . valros [AT] helsinki . fi.
A recent research paper has reported a positive effect of an online training tool on participants’ understanding of taildocking and enrichment legislation, as well as risk factors for tail biting. The training tool was aimed at official inspectors and others involved in enforcement of legislative requirements on pig farms. The research was a collaboration of 15 researchers from 9 EU countries, led by the University of Bristol, UK. The online training tool is free to use and is available in 7 different languages: English, French, German, Polish, Italian, Spanish and Dutch. It can be accessed here:
Hothersall, B., Whistance, L., Zedlacher, H., Algers, B., Andersson, E., Bracke, M., Courboulay, V., Ferrari, P., Leeb, C., Mullan, S., Nowicki, J., Meunier-Salaun, M-C., Schwarz, T., Stadig, L. & Main, D. 2016 Standardising the assessment of environmental enrichment and tail-docking legal requirements for finishing pigs in Europe. Animal Welfare 25:499-509.
An online training package providing a concise synthesis of the scientific data underpinning EU legislation on enrichment and taildocking of pigs was produced in seven languages, with the aim of improving consistency of professional judgements regarding legislation compliance on farms. In total, 158 participants who were official inspectors, certification scheme assessors and advisors from 16 EU countries completed an initial test and an online training package. Control group participants completed a second identical test before, and Training group participants after, viewing the training. In Section 1 of the test participants rated the importance of modifying environmental enrichment defined in nine scenarios from 1 (not important) to 10 (very important). Training significantly increased participants’ overall perception of the need for change. Participants then rated nine risk factors for tail-biting from 1 (no risk) to 10 (high risk). After training scores were better correlated with risk rankings already described by scientists. Scenarios relating to tail-docking and management were then described. Training significantly increased the proportion of respondents correctly identifying that a farm without tail lesions should stop tail-docking. Finally, participants rated the importance of modifying enrichment in three further scenarios. Training increased ratings in all three. The pattern of results indicated that participants’ roles influenced scores but overall the training improved: i) recognition of enrichments that, by virtue of their type or use by pigs, may be insufficient to achieve legislation compliance; ii) knowledge on risk factors for tail-biting; and iii) recognition of when routine tail-docking was occurring.
Note that the training tool is being used in Poland to train animal science students, farm assurance in the UK has shown recent interest in using the tool, and the Austrian pig health service is compiling a brochure based on EUWelNet on tail biting/enrichment material.
The last FareWellDock project meeting was held in Vejle, Denmark, October 27 and 28 2016.
We first discussed the stakeholder meeting in Grange, Ireland. We contributed to the meeting with several presentations. The presentations of the meeting can be accessed here. The video recordings will be available for some time after the meeting via this link. Striking differences exist between EU countries on their attitude and effort regarding tail docking.
The progress in the various work packages was discussed. We are on schedule in terms of milestones and deliverables.
Tail biting is a problem that may easily be overlooked. Sometimes all pigs in a pen turn out to be affected only after detecting the first pig. A standardized protocol could improve the recording and management of tail biting across research projects and across member states.
Over the past year our website has been visited more frequently (see the figure below).
This year (2016) FareWellDock project will end as a project and we intend to continue as a network. Interested scientists and other interested persons are invited to join the mailing list (please contact Anna.Valros @ helsinki.fi ).
Temporal changes in mechanical nociceptive thresholds in juvenile pigs subjected to surgical tail amputation: a model of injury induced by tail biting. By Di Giminiani, P., E. Malcolm, M. Leach, M. Herskin, D. Sandercock, S. Edwards, 2016. Royal Dublin Society: Abstracts book of the 24th International Pig Veterinary Society (IPVS) Congress, Dublin, Republic of Ireland 7-10th June 2016. p. 649.
Introduction: Tail biting is a global welfare problem in the pig industry leading to significant tail injury and potential carcass rejection. The temporal effects of such injuries and subsequent healing are presently unknown, although limb amputation in humans can lead to abnormal neural activity and decreased nociceptive thresholds. In order to evaluate potential sensitisation following tail damage, we created a model by surgical amputation of tails, and assessed mechanical nociceptive thresholds.
Materials and Methods: Surgical tail resection was performed to assess the influence of age, extent of tail amputated and time since amputation on thresholds of mechanical nociception. To evaluate the effect of age at the time of injury, female pigs underwent surgery at 9 weeks (±3 days ‘weaner’) (n=19) or 17 weeks (±3 days ‘finisher’) (n=43). The effect of time after amputation was evaluated on 24 pigs at 8 weeks, and 38 pigs at 16 weeks after surgery. The effect of the extent of tail amputated was assessed by assigning the pigs to 3 treatments (‘Intact’: sham-amputation; ‘short tail’: 2/3 of tail removed; ‘long tail’: 1/3 of tail removed). A Pressure Application Measurement device was used to record mechanical nociceptive thresholds (tail flick or tail clamp withdrawal responses). Within a single session, three stimuli were applied to a skin area proximal to the site of amputation, 3 days pre-surgery, 1 week and either 8 or 16 weeks post-amputation.
Results: Across the two amputation ages, results indicated that tail amputation induced a significant reduction (P<0.05) in mechanical nociceptive thresholds in short and long tails one week after surgery. The same treatment effect was observed at 16 weeks after amputation performed at 9 weeks of age (P<0.05). For surgeries performed at 17 weeks of age, thresholds tended to be lower in short compared to intact tails (P=0.081) and significantly lower (P<0.05) in long tail pigs 8 weeks after amputation. No significant difference was observed at 16 weeks following surgeries performed at 17 weeks of age.
Conclusion: These results show that surgical amputation of pig tails leads to decreased cutaneous mechanical nociceptive thresholds in the skin area proximal to the site of injury. Results indicated that severe tail injury occurring in the weaner period may be associated with sensitisation up to 16 weeks following the injury. In contrast, injuries occurring in the finishing period appeared to be associated with shorter lasting mechanical sensitisation, resolving within 16 weeks.