Tag Archives: Tail docking

EC Webinar on Tail biting and Tail docking of Pigs

4-6th October 2016: Meeting and Webinar on Actions to Prevent Tailbiting and Reduce Tail docking of Pigs

Note: The presentations of the meeting can be accessed here. The video  recordings will be available for some time after the meeting via this link.

The European Commission Directorate General for Health and Food Safety is organising a three day meeting at the offices of its Health and Food Audit and Analysis Directorate in Ireland on actions to prevent tailbiting and reduce tail docking of pigs.

The programme includes a wide range of relevant topics. It is delivered by experts from industry, Member State Competent Authorities, research bodies, EU institutions and NGOs.  Case studies will facilitate the exchange of good practice and workshops will focus on better solutions for the future. The work of the EU FareWellDock project will also be presented at this meeting.

The meeting is aimed at the authorities of Member States, international organizations, scientists, industry and NGOs.

The Agenda can be found below.

Please note that proceedings from this meeting, apart from breakout groups, will be broadcast live on the Internet and can be followed by logging in to the following links:

  • 4 October: 14:00- 16:45 GMT.

https://webcast.ec.europa.eu/meeting-on-actions-to-prevent-tailbiting-and-reduce-tail-docking-of-pigs-4

  • 5 October: 09:00- 16:30 GMT.

https://webcast.ec.europa.eu/meeting-on-actions-to-prevent-tailbiting-and-reduce-tail-docking-of-pigs-5

  • 6 October: 09:45-15:00 GMT.

https://webcast.ec.europa.eu/meeting-on-actions-to-prevent-tailbiting-and-reduce-tail-docking-of-pigs-6

Please send any questions you may have on the presentations to the functional mailbox: SANTE-IRL-WEBINAR-REARING-PIGS-WITH-INTACT-TAILS@ec.europa.eu and we will endeavour to answer as many as we can during the time for questions at the end of each presentation. If we cannot answer your question during the webinar, we will forward your question to the presenter for response after the event.

Curly tail

Agenda

MEETING ON ACTIONS TO PREVENT TAILBITING AND REDUCE TAIL DOCKING OF PIGS*

4th-6th October 2016, Dir F, Grange, Ireland

Tuesday 4th Oct

14:00 Opening Address, Background and objectives Dir. F. T Cassidy
14:20 Policy perspective Dir G. D Simonin
14:40 Farewelldock project Overview & Immediate and long term consequences of tail docking and tail biting for pig welfare. S Edwards/P Di Giminiani
15:00 Farewelldock project – Use of straw to reduce tail-biting as an alternative to tail-docking. L J Pedersen
15:20 Farewelldock project – Early detection of tail biting and the role of health. C Munsterhjelm
15:40 COST action (GroupHouseNet) with activities related to Tailbiting. A Prunier
16:00 Coffee break
16:30 Overview Report of Study Visits on Rearing Pigs with intact tails
“Problems/Solutions”
Breakout group discussion on measuring on-farm performance of criteria listed in Commission Recommendation (EU) 2016/336. Dir F
18:00 Close of day 1 – Bus to Knightsbrook Hotel
Wednesday 5th Oct

08:30 Bus from Knightsbrook Hotel
09:00 Change- Recent Experience from the poultry sector. B Eivers /N O’Nuallain
09:20 Funding possibilities for changes to housing/management leading to lower stress pig production.  P G Solernou
09:50 Maintaining low stress pig production-rearing pigs with intact tails. R Weber
10:30 Coffee break
11:00 Maintaining low stress pig production-rearing pigs with intact tails. J Lindahl
11:40 Maintaining low stress pig production-rearing pigs with intact tails. T.Tirkkonen
12:30 Lunch
13:30 NGO perspectives on developing and implementing a Quality Assurance scheme for improving the rearing of pigs and phasing out tail docking.  Bert Van Den Berg
14:00 Actions to improve the productivity and welfare of pigs with the aim of reducing tail docking.  D L Schroder
14:30 Actions to improve the productivity and welfare of pigs with the aim of reducing tail docking.  H Van der Velde
15:00 Coffee break
15:30 Actions to improve the productivity and welfare of pigs with the aim of reducing tail docking. C Veit
16:00 Actions to improve the productivity and welfare of pigs with the aim of reducing tail docking.  M Chapman-Rose
16:30 MS Communication strategies for improving the productivity and welfare of pigs with the aim of reducing tail docking. F2
Breakout group discussion on benchmarking farms at national level on levels of tail biting, tail docking and provision of sufficient enrichment  materia
17:45 Close of day 2 – Bus to Knightsbrook Hotel

Thursday 6th Oct

08:30 Bus from Knightsbrook Hotel
09:00 Overview of MS’ Action Plans to implement the Commission Recommendations (EU) 2016/336 of 8 March 2016. Dir F
09:45 COM programme on actions to prevent tailbiting and reduce tail docking of pigs. Dir F
10:30 Coffee break
11:00 Industry Initiatives to improve the rearing of pigs and phasing out tail docking.  H P Lahrmann
11:30 Discussion
12:30 Lunch
13:30 Conclusions and future actions
15:00 Departure of bus for airport / Departure of bus to hotel
17:30 Departure of bus for Dublin
*   Please note that proceedings from this meeting, apart from breakout groups, will be broadcast live on the Internet.

Effects of administration of a local anaesthetic and/or an NSAID and of docking length on the behaviour of piglets during 5 h after tail docking

Effects of administration of a local anaesthetic and/or an NSAID and of docking length on the behaviour of piglets during 5 h after tail docking

By M.S. Herskin, P. Di Giminiani, K. Thodberg, 2016. Research in Veterinary Science 108: 60–67.

Highlights

  • Lidocain reduced signs of procedural pain during tail docking in piglets but did not affect behaviour during 5 h after the procedure.
  • Meloxicam had only very marginal effects on behaviour of the piglets during and up to 5 h after tail docking.
  • Tail docking led to behavioural changes throughout the 5 h observation period.
  • Tail docking length affected procedural and post-procedural behaviour of the piglets.

Abstract

In many countries, piglets are tail docked to prevent tail biting. The aim of this study was 1) to evaluate the efficacy of a local anaesthetic and/or NSAID to reduce pain caused by tail docking; and 2) to examine interactions with docking length. This was examined in 295 piglets docked by hot iron cautery 2–4 days after birth and based on behaviour during docking as well as the following 5 h. The study involved three main factors: local anaesthetic (Lidocain), NSAID (Meloxicam) and docking length. Either 100%, 75%, 50% or 25% of the tails were left on the body of the piglets. Irrespective of the tail length, tail docking led to signs of procedural pain, which could be reduced by administration of Lidocain. Preemptive use of Meloxicam did not affect the signs of procedural pain. The results show that tail docking led to behavioural changes throughout the 5 h observation period indicating that effects of this management routine are more persistent than earlier suggested, and suggesting that docking length may influence the post-surgical behaviour of piglets. By use of the present sites of injection and dosages, neither local anaesthetic nor NSAID had marked effects on post-surgical behavioural changes induced by tail docking. Hence, if tail docking is to be performed, more research is needed in order to develop practical methods for on-farm piglet pain relief.

Tail docking: The final cut?

Tail docking: The final cut? By Monique Pairis-Garcia. You can read the first part of this article here. For the second part see the original at the Pig Progress site (published August 8, 2016).

Tail docking is applied to young piglets to avoid a potential problem later of tail biting. However, should the root of the problem be looked at instead of using this preemptive measure?

Tail docking is routinely performed on farms as a means to decrease the prevalence of tail biting. Tail biting is an abnormal redirected exploratory behaviour that results in mild to severe injury of pen mate’s tails. Several factors have been associated with tail biting behaviour including environment, nutrition, gender, genetics and health status.

Tail docking of piglets has and continues to be highly criticised in both the US and Europe. This is primarily driven by the fact that tail docking is a painful procedure as indicated by changes to the physiology and behaviour of pigs who are tail docked.

Eliminate tail docking and control tail biting

Most recently, European countries have taken a stance to eliminate this management practice by managing the problems which lead to tail biting in the first place. Several research projects including FareWellDock have been established to provide scientific research to determine the best practices to eliminate tail docking and control tail biting. Although several factors can contribute to tail biting, research has consistently demonstrated that the absence of material for manipulation increases risk of tail biting. Several enrichment objects including chains, rubber hoses, car tires, straw and peat moss have shown to decrease tail biting but not necessarily eliminate the behaviour altogether.

Unlike the European approach, the US is nowhere near implementing the elimination of tail docking on farm. Tail docking is still performed routinely on commercial swine operations in the US. Farms which are not tail docking are either smaller farms which provide outdoor access to pigs or farms on specified animal welfare friendly programmes like Animal Welfare Approved, American Humane and Certified Humane.

For the second part of this article (on the probability of eliminating tail docking and the value of enrichment) see the original at the Pig Progress site (and see also the comment section).

 

What are the effects of tail docking on piglets?

What are the effects of tail docking on piglets? Interview with Dr Pierpaolo Di Giminiani by Vincent Ter Beek in Pig Progress (August 8, 2016). Here you find the first half of the interview. The whole article can be found on Pig Progress.

The practice of tail docking is applied to young piglets to avoid a potential later problem of tail biting. But are there effects of docking on piglets? Very few researchers have asked that question, found Dr Pierpaolo Di Giminiani, researcher at Newcastle University, UK.

Is a tail actually a sensitive part of the pig’s body? Dr Pierpaolo Di Giminiani thinks for a while and says, “That is a very good question! I would say it is not more or less sensitive than other parts of the body. The tail is full of neuro-anatomical structures responsible for the pain response. It is comparable to our human skin.” Unlike in many other animals, the pig’s tail may not have a wide range of functions. At best it serves to chase insects away and when in a curl, it gives an indication of the animal’s health. Still, when something happens to that tail, whether this be being docked or bitten, this body part responds like any other.

Biography

Dr Pierpaolo Di Giminiani is a research associate with a focus on ethology (animal behaviour) at Newcastle University, UK. During his graduate studies at Linköping University in Sweden, he studied the cognitive impairment caused by anaesthetic protocols in rodents. At his doctorate at Aarhus University, Denmark, he focused on the assessment of behavioural measures of pain in pigs as a result of cutaneous inflammation. Currently, he investigates pain in pigs in relation to the practice of tail docking in piglets and tail injuries in older pigs.

Tail docking – and especially the effects of tail docking on piglets – has been the focus of Di Giminiani’s studies since the beginning of 2014. They form part of the FareWellDock research programme, an international conglomerate funded by the European Union, zooming in on the common problem of tail biting, the preventive solution of tail docking, virtually common everywhere in Europe, and what can be done to overcome both. Especially tail docking of piglets is a practice which is increasingly frowned upon in some European countries. For more information on FareWellDock, see box below.

Di Giminiani’s studies have mainly centred on the question of whether piglets in the short and long term suffer from any pain from tail docking. In an interview with Pig Progress, Di Giminiani points to pain being a very complex experience and it being difficult to measure properly. He says, “I find it fascinating because there is a lot that we can do, especially in a species like the pig. A lot has been done in humans and laboratory animals and we now have the opportunity to apply novel techniques in other animal species. In addition, pain mitigation is often not provided or done so arbitrarily due to the lack of valid measures of pain in non-verbal animals. Therefore, it still remains one of the big open questions in research.”

Measuring pain in animals

In many other animal studies, Di Giminiani explains, research on pain sensitivity is fairly common. Before he set himself onto the theme of pain in piglets, an academic journey took him from his native Italy to San Diego, United States and later Linköping, Sweden, to learn and discover more on pain perception in laboratory rodents.

In pigs, however, everything was different, he says, as similar research appeared to be virtually absent in pigs when starting his PhD in Denmark at Aarhus University. Indeed, a bit strange, considering that pigs have an important role to play virtually all over the world – and considering the fact that from a medical perspective, pigs and humans are very similar.

The current research on pain sensitivity around tail docking in piglets at Newcastle University roughly revolves around three questions, Di Giminiani explains:

Is pain actually occurring or not and how long does it last?
What is the level of pain experience for piglets?
Based on the outcome, what can be done – for instance the use of painkillers?
Di Giminiani says, “Basically, there are 2 common methods to assess pain in animals:

To observe spontaneous behaviour. You just observe the activity of the animals, e.g. how much they walk – their locomotion – how much they lie, how much they stand, how do they drink, how do they eat, etcetera.
“Another method revolves around stimulus and reception – how do animals react to certain controlled challenges? We apply a controlled challenge to evoke a reaction.” This last method had not been applied in pigs a lot, but was used at Newcastle University to figure out short and long-term effects of tail docking on piglets.
Di Giminiani’s research team applied a gas-heated iron for tail docking, so that any wound would immediately be closed to avoid infections. He says, “In addition to measuring responses to controlled stimuli, we developed a grimace scale to measure the facial expressions of piglets. They do seem to grimace, particularly that they squint with their eyes in the minutes immediately following tail docking.” A full scientific paper related to the findings will be sent for publication in the summer of 2016.

For the last three sections of this interview (Pain in animals in the longer term; Does it matter?; FareWellDock) see the original article, as well as several related articles, on the Pig Progress site.

Tail docking using hot iron cautery

On-farm tail biting prevention in long-tailed pigs – results from a producer questionnaire in Finland

On-farm tail biting prevention in long-tailed pigs – results from a producer questionnaire in Finland. By Valros, A., C. Munsterhjelm, L. Hänninen, T. Kauppinen, M. Heinonen, 2016. Royal Dublin Society: Abstracts book of the 24th International Pig Veterinary Society (IPVS) Congress, Dublin, Republic of Ireland 7-10th June 2016. p. 144.

Abstract

Introduction: Tail biting is a serious welfare problem in pigs, causing substantial economic losses. In the majority of the EU countries, tail docking is used to reduce the incidence of tail biting. However, many of the risk factors for tail biting are related to suboptimal management, and tail biting can be reduced by corrective management decisions. There are few studies on which preventive measures producers themselves value as most important.

Materials and Methods: A questionnaire was distributed via slaughterhouse webpages in 2015. Producers were asked to score the importance of handling different tail-biting risk factors on their own farms, as well as about which manipulable materials they use, and find efficient. In addition, we asked about their opinions on tail biting and tail docking. A total of 70 producers replied, 54 of these replies were regarding fattening pigs, and 16 regarding weaned pigs. The size of the pig units varied between 100 and 6400 pigs, with an average of 1307 pigs. Finland banned tail docking in 2003, so all farms raised long-tailed pigs only.

Results: On average, the producers reported a prevalence of tail biting of 2,3% on their farms, which corresponds well with values reported at Finnish abattoirs. Most producers found tail biting not to be a big problem on their farms and 62% of the farmers found it very unlikely that they would raise tail docked pigs even if it was legal in Finland. The more tail biting reported on the farm, the more problematic the farmers found tail biting, and the more prone they were to say they would probably tail dock if they were allowed to. According to the Finnish producers, the most important factor to prevent tail biting is that there is enough feeding space for the pigs. Altogether, four feeding-related risk factors were included in the top-10 measures to prevent tail biting. Also pig health was considered very important, as well as a good quality of piglets, and controlling air movements in the pen. Straw, newspaper, hay and cardboard were considered the most efficient manipulable materials to prevent tail biting. If tail biting has already started in the pen, the producers ranked identifying and removing the tail biter from the pen as most important, followed by adding bedding-type manipulable materials.

Conclusion: The results are partly in accordance with experimental and epidemiological studies on risk factors for tail biting, but the high focus on feeding-related and health factors is interesting. Finnish farmers appear to handle the tail docking ban well, and do not, on average, find tail biting a very serious problem.

The perception of pain by pigs and implications for farm and veterinary practice

The perception of pain by pigs and implications for farm and veterinary practice. Edwards, S., 2016. Royal Dublin Society: Abstracts book of the 24th International Pig Veterinary Society (IPVS) Congress, Dublin, Republic of Ireland 7-10th June 2016. p. 13-17.

Abstract

“Freedom from pain, injury and disease” is one of the fundamental aspects of good animal welfare. However, in commercial pig production there are a number of situations where animals may experience pain. This may result from procedures carried out deliberately for management purposes, or from spontaneous health disorders. In order to make decisions on the ethical justification of procedures and the provision of pain alleviation by appropriate anaesthesia and analgesia, it is necessary to assess the intensity and duration of pain experienced by the animals. A number of behavioural, physiological and molecular methods now exist for such assessment but, since pain is a subjective experience which the individual may express in different ways, interpreting these measures can be a challenge. Better methods are required for the practical on-farm assessment of pain and the provision of analgesia when this occurs.

Paper available in the proceedings.

Traumatic neuroma development in tail docked piglets is not associated with long-term changes in spinal nociceptive processing

Traumatic neuroma development in tail docked piglets is not associated with long-term changes in spinal nociceptive processing. By Sandercock, D., S. Smith, J. Coe, P. Di Giminiani, 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. 611.

Abstract

Introduction: Concerns exist over the long term consequences for tail stump pain experienced by piglets after docking, especially in relation to traumatic neuroma development in caudal nerves after docking injury. Neuroma formation may cause detrimental sensory changes in the tail due to altered axonal excitability leading to abnormal sensation or pain.

Aims: To characterize pig tail histopathology at time intervals up to 16 weeks after tail docking and to measure expression of key neuropeptides in caudal dorsal root ganglia and spinal cord neurons associated with (i) peripheral nerve regeneration; activating transcription factor-3 (ATF3), (ii) inflammatory pain; Calcitonin gene-related peptide (CGRP) and (iii) the maintenance of chronic pain; N-methyl D-aspartate (NMDA) ionotropic glutamate receptor subtype 2B (GRIN2B) at the same time points after tail docking injury.

Materials and Methods: Thirty-two female piglets (Landrace/Large White x synthetic sireline) were used (16 docked/16 sham-docked). Piglets were tail docked (amputation of approx. 2/3 of the tail) on post-natal day 3 using a gas hot docking iron. Equivalent sham-docked piglets served as intact controls. Pigs were euthanized by barbiturate overdose 1, 4, 8 and 16 weeks after sham/tail docking. Tail stumps (2 cm) were collected post-mortem for histopathological assessment. Caudal dorsal root ganglia (Ca1-Ca4+) and associated spinal cord were collected for gene expression analysis by real-time quantitative PCR of mRNA.

Results: Non-specific epidermal and dermal changes associated with healing were observed after tail docking. Mild inflammation, ulceration and oedema were present at 1 week. Traumatic neuroma development was a consistent feature from 4 weeks after tail docking. Neuroma axonal dispersion in the tail stump was on-going 16 weeks after tail docking. ATF-3 mRNA was significantly upregulated in caudal DRGs up to 8 weeks after tail docking, but did not differ at 16 weeks compared with sham controls. Both CGRP and GRIN2B mRNA expression was significantly upregulated 1 week after tail docking in caudal spinal cord neurons but were not significantly different from sham-docked pigs thereafter.

Conclusion: Histopathological lesions that occur shortly after tail docking (beyond 1 week) are not likely to induce or maintain pain. The effects of tail docking on peripheral nerve axonal proliferation and dispersion are relatively short-lived and, although still present, are attenuated by 16 weeks after tail docking injury. Changes in peripheral and spinal nociceptive processing associated with possible inflammatory and chronic pain appear to resolve by 4 weeks after tail docking injury.

Poster Sandercock IPVS

FareWellDock Edinburgh Satellite Meeting

On July 12th the FareWellDock consortium hosted a satellite meeting and videoconference at the Roslin Institute Building near Edinburgh to coincide with the 50th conference of the International Society for Applied Ethology. The aim of the satellite meeting was to invite researchers involved in other European projects on tail docking and biting to share their work and ideas with the consortium.

The speakers gave four excellent presentations which generated interesting discussions and more ideas for planning future work (see brief summaries below)

Updates of the three work packages were also presented at the meeting. Since the last meeting in March, several more articles on tail docking and biting have been published and a number are near completion. Work progress in all three work packages appears to be on track.

Emphasis was placed upon generating and circulating draft fact sheets from the 3 work packages before the FVO Stakeholder Meeting in Grange, Republic of Ireland on October 4-6th 2016.

Sabine Dippel, a researcher at the Federal Research Institute of Animal Health (FLI), provided a comprehensive overview of “Current tail biting projects in Germany” and the summarised outputs from 51 different projects ranging from those focussed on basic science to feasibility and survey-based studies. Preliminary findings suggested that:
• Undocked weaner pigs were at higher risk of tail biting than undocked fattening pigs.
• Farmers need to gain experience in observing pigs
• Farms need to change step-by-step towards intact tails
• Focus on farm-individual optimisation
• Greater coordination between production stages
• Advice, training, knowledge transfer were essential to achieving these aims
Tail biting pigs
Valérie Courboulay a researcher at IFIP (French Institute for the pig and pork industry) provided an overview of several IFIP related studies on tail biting and dissemination of information in the form of technical datasheets to French farmers. Data presented from studies where pain relief (meloxicam) was provided at the time of docking and castration showed marginal affects on general behaviours, except for increased time spent sitting. When investigating tail posture, pigs with more severe tail lesions (score 3) exhibited more tail-down posture than pigs with minor tail or no tail lesions (score 2-0). A recent study has been undertaken to develop a model of cannibalism in pigs based on frustration of exploratory behaviours by providing environmental enrichment (progressive supply) and straw in the post weaning period and then some groups were reared with or without environmental enrichment for a short duration in the fattening period. The results showed that:
• Removal of enrichment between the post weaning and fattening periods is not sufficient to induce tail biting
• Providing objects for a few days and removing them is not sufficient to induce tail biting
• Frustration of investigative behaviour, that is considered as a major risk factor, is not sufficient to induce tail biting

INRA factsheet on pain

Jen-yun Chou, a first year PhD student working at Teagasc in the Republic of Ireland, presented preliminary findings from her studies into the use of wood as a strategy to reduce the risk of tail biting in pigs managed on slatted floors. The potential use of wood as a manipulable material is viewed positively in Irish production systems due to the problems of slurry removal caused by loose straw in fully slatted systems. To date, preliminary data have shown that softwoods such as spruce and scots pine are more readily used by the pigs compared to more hardwoods such as larch and beech.
• Spruce was used up most quickly both in terms of length and weight loss, possibly due to its softness.
• There is a tendency of more interaction with the wood by pigs in pens provided with spruce.
• In terms of texture and moisture spruce is a good option for enrichment but the cost may be a drawback
• Different wood types did not affect harmful behaviours, pig physical measures and production.
• Correlation between ear lesion and tear staining scorings implies a potential welfare assessment method on farm due to easy visibility.
• Correlation between tail posture and lesion shows that posture could be an indicator of tail biting

Chewed wood

Anna Sinclair, a first year SRUC PhD student currently working at the Institut National de la Recherché Agronomique (INRA), presented preliminary findings from studies into the behavioural and neural/cellular consequences of tooth resection in commercial pigs at its implications for pig welfare. Although this work was not directly related to tail docking or biting it is a project that was developed through on-going collaborative research by Dr. Armelle Prunier ay INRA and Dr. Dale Sandercock at SRUC within the FareWellDock project, addressing the issue of early life pain in livestock. Preliminary data were presented on the effects of tooth clipping and tooth grinding on tooth length and tooth/gum injury, haematological measures, live weight/growth rates, general, stress and pain related behavioural measures. Findings to date have shown that:
• Tooth damage was readily observed but variable
• Maxillary incisors are most consistently affected
• Clipping results in tooth and gum bleeding
• Growth rates are unaffected
• Pigs exhibit reduced activity after tooth treatments
• Pigs keep their ears back less and their tails down more, although this could be handling effect
• High variation at this stage – more data are required

Tooth treatment

Application of a handheld Pressure Application Measurement device for the characterisation of mechanical nociceptive thresholds in intact pig tails

Application of a handheld Pressure Application Measurement device for the characterisation of mechanical nociceptive thresholds in intact pig tails. By Pierpaolo Di Giminiani, Dale A. Sandercock, Emma M. Malcolm, Matthew C. Leach, Mette S. Herskin and Sandra A. Edwards. 2016. Physiology & Behavior 165: 119–126.

Highlights

• Mechanical nociceptive thresholds were quantified for the first time in pig tails.
• The PAM device allowed determining anatomical and age-specific thresholds in pigs.
• A platform for the assessment of painful conditions in pigs is proposed.

Abstract

The assessment of nociceptive thresholds is employed in animals and humans to evaluate changes in sensitivity potentially arising from tissue damage. Its application on the intact pig tail might represent a suitable method to assess changes in nociceptive thresholds arising from tail injury, such as tail docking or tail biting. The Pressure Application Measurement (PAM) device is used here for the first time on the tail of pigs to determine the reliability of the methods and to provide novel data on mechanical nociceptive thresholds (MNT) associated with four different age groups (9, 17, 24 and 32 weeks) and with proximity of the target region to the body of the animal. We recorded an overall acceptable level of intra-individual reliability, with mean values of CV ranging between 30.1 and 32.6%. Across all age groups, the first single measurement of MNT recorded at region 1 (proximal) was significantly higher (P b 0.05) than the following two. This was not observed at tail regions 2 and 3 (more distal). Age had a significant effect (P b 0.05) on the mean thresholds of nociception with increasing age corresponding to higher thresholds. Furthermore, a significant effect of proximity of tail region to the body was observed (P b 0.05), with MNT being higher in the proximal tail region in pigs of 9, 17 and 24 weeks of age.
There was also a significant positive correlation (P b 0.05) between mechanical nociceptive thresholds and age/body size of the animals.
To the best of our knowledge, no other investigation of tail nociceptive thresholds has been performed with the PAM device or alternative methods to obtain mechanical nociceptive thresholds in intact tails of pigs of different age/body size. The reliability of the data obtained with the PAM device support its use in the measurement of mechanical nociceptive threshold in pig tails. This methodological approach is possibly suitable for assessing changes in tail stump MNTs after tail injury caused by tail docking and biting.