Tail biting is a common problem in growing–finishing pigs, which can compromise health, growth, and welfare of pigs. Because tail biting is an abnormal behavior performed by tail biters toward victimized pigs, understanding these pigs may help us solve the problem. This study was conducted to evaluate immune function of tail biters and victimized pigs. Pigs (n = 240; 25.7 ± 2.9 kg initial weight) were housed in 8 pens of 30 pigs for 16 wk. Once visible blood on a tail appeared, pigs in that pen were assessed daily for tail score (0 = no damage, 1 = healed lesions, 2 = visible blood without swelling, 3 = swelling and signs of infection, and 4 = partial or total loss of the tail). Victimized pigs were defined as pigs with tail scores equal to or greater than 2. Meanwhile, a 2-h observation was conducted for 2 consecutive days to identify tail biters. In each pen in which tail biting occurred, blood samples were collected from victimized pigs on the day that tail biting was first observed as well as from tail biters and 2 control pigs with no sign of tail damage. Fourteen biters (6 barrows and 8 gilts), 30 victimized pigs (21 barrows and 9 gilts), and 28 control pigs (14 barrows and 14 gilts) were identified for blood sampling. Total serum protein and IgG concentrations were analyzed using the spectrophotometric method. Data were analyzed using the Glimmix model of SAS (SAS Inst. Inc., Cary, NC). Compared with control and victimized pigs, tail biters had lower total serum protein (P = 0.01; Table 018) and IgG concentrations (P = 0.01), suggesting poor immunity. There were no differences in total serum protein or IgG concentrations between control and victimized pigs. These preliminary results suggest that tail biters may experience compromised immunity.
Tail docking performed in order to avoid tail biting in fattening pigs is criticized. In order to assess its short term consequences, two experiments were realized. The first one performed on 160 piglets from 32 litters was focussed on the behavioural consequences and the growth performance. The aim of the second one was to determine the effects of tail docking on the adrenal (plasma cortisol and ACTH) and sympathetic (measurement of glucose and lactate released from catecholamine-induced mobilization of glycogen) axes in 20 piglets from 7 litters which were catheterized at birth. In the first experiment, there were 5 treatments: tail docking, tail docking + a cold analgesic spray, control handling, control handling + spray, no handling. In the second experiment, the same treatments were run, except the fourth one. Treatments were applied the day after birth and tail was docked with an iron docking (cautery). During treatment, tail docking caused more movements (legs and/or body) and howls (P < 0.05). During the 20 s following treatment, docked piglets demonstrated more tail jamming and wagging (P < 0.05). Both types of docking consequences were attenuated when the cold spray was used. During the following 12 hours, time spent by the piglets to rest or to be active at the sow udder was similar in the 5 groups. Growth rate during the first week of life and the occurrence of injuries at the tail did not differ between groups (P > 0.1). Tail docking with or without the cold spray had no marked effects on the patterns of plasma cortisol, ACTH, glucose and lactate. In conclusion, tail docking causes probably pain of moderate amplitude.
In boars, sexually motivated mounting can not only cause problems such as lameness, but penile injuries are also reported. The relevance of penis biting in boars is discussed controversially, but reliable data is missing. In the present study, boars ( n = 435) and barrows ( n = 85) from experimental farms were therefore evaluated for scars, fresh wounds and severe injuries of the penis. Similarly, 321 boars from 11 farms specializing in pork production with boars, and 15 sexually mature wild boars from the hunting season of 2015/16 were included in the study. In domestic boars, a high incidence of penile injuries was obvious (76.6%-87.0% of animals with scars and/or wounds at experimental farms, 64.0%-94.9% at commercial farms). The number of boars with severe injuries was in a similar range in both groups (7.3% vs. 9.3%). At commercial farms, the number of scars but not that of fresh wounds increased per animal with age by 0.3 per week. Moreover, raising boars in mixed groups led to about a 1.5 times higher number of scars than in single-sex groups. In wild boars, a considerable proportion of animals (40%) revealed penile injuries, which were even severe in three animals. We therefore conclude that penis biting is a highly relevant and severe welfare problem in the male pig population, but this phenomenon is not limited to intensive production systems.
Notes:
In commerical pig production penis biting is a problem of intact boars. The examined barrows were all free of scars, wounds, severe injuries or suppuration.
For pictures of just how severe penis biting in pigs can be see the article Penisbeissen ein blutiges Phanomen in der Ebermast.
Tail lesions are outcomes of tail biting behaviour and reflective of impaired welfare in pigs. This work is part of a study which aims to validate tail lesions as possible iceberg indicators to be included in the meat inspection process at slaughter (PIGWELFIND). Twenty farrow-to-finish Irish pig farms were visited. On each farm, 18 randomly selected pens of first (n=6) and second (n=6) weaner stage and finisher (n=6) pigs were inspected. Pigs were observed for 10 min and the number of pigs with tail, ear, flank and skin lesions and the number showing signs of other health deviations (e.g. lameness, sickness) were recorded. All occurrence behaviour sampling was used to record frequency of coughing and sneezing (5 min) and tail-, ear-, and flank biting, fighting and mounting behaviour (5 min). Welfare conditions were expressed as percentage of pigs in a pen and behaviours were expressed per pig to correct for different numbers of pigs per pen (32.1±16.0 pigs/pen). Mixed model equation methods were used to analyse the effect of welfare conditions and behaviours on percentage of pigs with tail lesions. Farms and stage were included as fixed effects and welfare and behaviour indicators were included as covariates. Pen within stage by farm was included as random effect. Results for covariates are presented as regression coefficients. On average, 7.4% of pigs in a pen had tail lesions. Preliminary results show that the percentage of pigs with tail lesions was greater for pens with a higher percentage of pigs with skin lesions but lower for pens with a higher percentage of sick pigs (P<0.05). Furthermore, the percentage of pigs with tail lesions was positively associated with tail biting (P<0.001).
Results suggest that tail lesions may have potential as iceberg indicators for pig welfare. However, more research is needed to further elucidate the nature of these associations.
Tail biting and aggression between finishing pigs are injurious behaviours affecting health, welfare and productivity. Solutions to these behavioural problems have been researched extensively and include tail docking, provision of environmental enrichment and increasing group stability. However, their effectiveness differs considerably between research labs and commercial practice, and between farms. It is obvious that farmers themselves play a key role in the effectiveness of these ?standard recommendations?. Experimenting and sharing their experiences with scientists and advisors will help to progress existing knowledge into farm-specific tailor-made solutions.
To facilitate the exchange of ideas, and to monitor the effects of these solutions, it is important that there is a common definition and description of injurious behaviours. Therefore, together with pig farmers, PigWatch aims to develop and apply animal based measures to avoid the pain, frustration and negative emotional states associated with tail biting and aggression in finishing pigs.
As a starting point the knowledge generated in FareWellDock and EU Welnet will be used, as well as national initiatives from the participating countries. PigWatch continues these developments at two levels: on-farm and at the abattoir.
The first WP develops animal based warning signals to identify and, if possible predict outbreaks of tail biting or fighting on farm. This will allow farmers to respond to imminent problems before they get out of hand. It includes precision farming techniques for detection of behavioural activity, and lesion detection based on presence of haemoglobin. Finally, it develops protocols for visual scoring of behavioural and other warning signals.
The second WP uses animal based measures to monitor tail biting and skin lesion incidence through routine automated data collection at the slaughter plant. The data will facilitate comparisons (bench marking) between farms, and monitoring the effects of solutions over time. The technology is based on analysis of digital images of live pigs and carcasses. This will be developed in a laboratory setting, validated on a slaughter house and tested in a commercial situation.
The pig farming community will be involved through the whole project, via Farmer Focus Groups which help to develop and disseminate the innovative techniques proposed. PigWatch aims to do this in the five participating countries: France, Denmark, Switzerland, Germany and The Netherlands.
Principle investigator: Dr. Hans Spoolder, Wageningen UR Livestock Research (WLR), Netherlands
This first week of February 2016 two items related to tail biting appeared in farmers’ press in The Netherlands. In addition, we recently provided input into a European project on the welfare of poultry, which will be reported on briefly below.
One news item announced that farmers are invited at the Intensive Farming Fair in Venray (LIV Venray), March 1-3 2016. At the fair two finished tail-biting projects will be presented and discussed with entrepreneurs who are active in intensive farming. One of the projects is ‘Keeping pigs with intact tails’.
The other item was a report on the German tail biting (Ringelschwanz-)project. First results of the curly-tail project in North-Rhine Westphalia showed that more than one quarter of piglets at 15 participating research farms had damaged tails before the end of the rearing period. At some farms half of the tails had been bitten. At the 15 farms participating in the study 30-94 piglets had been reared on each farm without tail docking. Outbreaks of tail biting appeared to be associated with streptococcus infections. Prevention and intervention strategies included providing dried maize silage or alfalfa hay twice daily and the isolation of biters respectively. Most tail biting occurred between week 2 and 4 after weaning. This level of tail biting is not so good news. If these levels of tail biting would persist, it may indicate that intensive systems cannot be made compatible with acceptable levels of animal welfare. Fortunately, however, experiences in Finland indicate that it should be possible to keep undocked pigs in conventional systems at much lower levels of tail biting (around 2% based on slaughter house data).
The German farmers union and North-Rhine Westphalia have agreed 1.5 years ago that they intend to stop tail docking by 2017. This will be done provided on-farm research shows that tail biting among pigs with intact tails does not reduce animal welfare. The general expectation is that the objective of safely quitting tail docking cannot be met.
From a Dutch research perspective two notes appear to be relevant:
The first is that our semantic-modelling approach provides a unique methodology to determine/assess the cut-off point between the welfare impacts of tail biting and tail docking using formalised biological reasoning and scientific evidence. In this computation one must take into account all relevant aspects: So, not only the point that the welfare of tail bitten pigs is reduced due to blunt trauma (biting) compared to the sharp trauma of tail docking at an earlier age. But also the point must be recognised that the welfare of tail biting pigs may relatively be improved when they can bite their penmates’ tails, compared to when they cannot (other things being equal, i.e. lack of suitable enrichment). What matters for welfare as considered from the animals’ point of view is the extent to which they can satisfy their needs, e.g. for biting and the expression of species-specific foraging behaviour, taking into account also the activation of coping mechanisms such as redirected and harmful-social behaviours.
The second thing to note about the results of the German research project is the following. In addition to taking note of the bad news (many bitten tails, which has to be taken seriously, perhaps even to the point that the conclusion must be drawn that intensive systems are not compatible with acceptable animal welfare), one may also try to move forwards for the time being by focussing on the good news: Two out of the 15 pilot farms in Germany managed to keep all piglets’ tails intact. Other farms may learn from what was done on these farms to keep tails intact. Furthermore, since the EC Directive requires that all farms try to periodically keep at least some intact pigs, a 10% success rate could provide sufficient scope for progress at the population level, even when the causes of the success are poorly understood. This can be concluded from a methodology we designed previously to solve complex welfare problems like feather pecking in poultry and tail biting in pigs. This methodology has been called ‘Intelligent Natural Design’ (INO in Dutch; see also Bracke, 2010). It basically uses evolution to select the best farms to make increasing progress towards the objective of completely stopping the practice of routine tail docking in pig farming.
Countering the routine practices of tail docking and beak trimming, as well as preventing and treating outbreaks of tail biting and feather pecking requires an understanding of tipping points. Recently, we modified our tipping-bucket model for tail biting for inclusion on the Henhub website. This website, which is part of the Hennovation project, gives information about welfare issues in poultry, esp. (at present) feather pecking. On that site the modified tipping-bucket model can be found under the post describing the mechanism of feather pecking.
Tipping-bucket model of tail biting in pigs
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Bracke, M.B.M. 2010. Towards long(er) pig tails: New strategy to solve animal welfare problems. In: Lidfors, L., Blokhuis, H., Keeling, L., Proceedings of the 44th Congress of the ISAE, August 4-7 2010, Wageningen Academic Publishers, Wageningen, p. 135. (Poster, ISAE 2010, Uppsala, Sweden, Aug 4-7.
A 4-year project of “Strategies to reduce the risk of tail biting in pigs managed on slatted floors” has started. It is a collaboration between Teagasc, SRUC and the University of Edinburgh.
Below is a poster on the project presented in the Teagasc Pig Farmers’ Conference 2015.
The project will aim to explore ways to reduce tail-biting on slatted floor systems where straw is not available by environmental enrichment and nutritional strategies.
The enrichments used at the moment are compressed straw and different wood types.
Later the project will also investigate the effects of various lengths of tails, measures to predict tail-biting outbreaks and methods to interfere effectively.
The project will be supervised by Dr Keelin O’Driscoll (Teagasc), Dr Rick D’Eath (SRUC), Dr Dale Sandercock (SRUC), and Prof Natalie Waran (University of Edinburgh).
Dr Amy Haigh is the postdoctoral researcher working together on this project in Teagasc, and Dr Laura Boyle and Dr Edgar Garcia Manzanilla are also the collaborating researchers in Teagasc. I (Jen-Yun) am the PhD student on this project.
Description are provided by the Actions directly via e-COST.
The GroupHouseNet aim is to provide the European livestock industry with innovations in breeding and management for pigs and poultry that are needed for a successful transition to large group housing systems without necessitating painful tail docking and beak trimming. Allowing the animals greater opportunities to display their species-specific behaviour while avoiding the routine use of painful procedures, group housing of unmutilated animals sits at the core of the new animal welfare paradigm driven by consumer demand. Group housing is associated with increased risks of damaging behaviours among the animals, such as feather pecking, aggression and cannibalism in laying hens and tail biting, bellynosing, excessive aggression and cannibalism in pigs. Recent research suggests the key to reducing the incidence of these behaviours lies in refining and applying methods of genetic selection, and developing husbandry innovations that improve early and later life conditions – which is exactly what GroupHouseNet will use the COST Action framework and tools to do. GroupHouseNet brings together researchers and industrial partners dealing with animal breeding and genetics, animal nutrition, epidemiology, engineering, animal behaviour and welfare, epigenetics, immunology, (neuro)physiology, economics and ethics. To strengthen the scientific and technological basis in these areas the Action will facilitate knowledge sharing, creation and application in pigs and laying hens in both experimental and commercial environments. The activities will be conducted in an open, output-oriented transnational, multisectorial, and multidisciplinary research and development network emphasising COST Excellence and Inclusiveness Policy.
Proposer of the action: Prof Andrew Janczak
(action arising in part from the FareWellDock project).
As a follow-up to the German tail biting research review, German federal research institutions are currently making arrangements for better cooperation and coordination of their tail biting research. Representatives agreed to update an existing lesion scoring format from 2011 in such a way that it can be used to score tail and ear lesions in basic research as well as on-farm projects. In addition, a web-based database for tail biting experiments and projects will be launched in 2016 in order to facilitate knowledge exchange. The database will be based at the Institute of Animal Welfare and Animal Husbandry (ITT) within the German Federal Research Institute for Animal Health (FLI).
We investigated the effect of straw amount on pigs’ time spent manipulating straw.
We investigated the effect of straw amount on pigs’ simultaneous straw manipulation.
Increasing straw from 10 to 430 g/pig/day increased both measures.
Increasing straw above approx. 250 g did not significantly increase the behaviour further.
Abstract
According to European legislation, pigs must have permanent access to sufficient quantity of material to enable manipulation activities. However, few studies have quantified how much straw is needed to fulfil the requirements of growing pigs. We investigated the effect of increasing amount of straw on pigs’ manipulation of the straw, and hypothesised that after a certain point increasing straw amount will no longer increase oral manipulation further. From 30 to 80 kg live weight, pigs were housed in 90 groups of 18 pigs in pens (5.48 m × 2.48 m) with partly slatted concrete floor and daily provided with fresh uncut straw onto the solid part of the floor. Experimental treatments were 10, 80, 150, 220, 290, 360, 430 or 500 g straw per pig and day. At 40 and 80 kg live weight, the time spent in oral manipulation of the straw by three focal pigs per pen (large, medium and small sized) were recorded along with the percentage of pigs manipulating straw simultaneously. This was recorded in three 1-h intervals (1 h before and 1 h after straw allocation in the morning, as well as from 17 to 18 h in the afternoon). With increasing quantity of straw provided, we found a curvilinear (P < 0.01) increase in the time spent in oral manipulation of the straw. Smaller pigs spent more time manipulating straw than larger and medium sized pigs (367, 274 and 252 s/h for small, medium and large sized pigs, respectively; P < 0.001), and pigs spent more time manipulating straw at 40 kg than 80 kg live weight (356 vs. 250 s/h; P < 0.001). At both live weights, pigs spent most time manipulating straw during the hour after allocation of straw. Similar effects of increasing amounts of straw were found for the percentage of pigs engaged in simultaneous manipulation of the straw. Post hoc analyses were applied to estimate the point, after which additional straw did not increase manipulation of straw any further. For the time spent manipulating straw the estimated change point was 253 (approx. 95% confidence limits (CL) 148–358) g straw per pig and day. For the number of pigs simultaneously manipulating straw the change point was 248 (CL 191–304) g straw per pig and day. These results show that increasing the quantity of straw from minimal to approximately 250 g per pig and day increased the time spent in oral manipulation of the straw, as well as the occurrence of simultaneous straw manipulation.
Hence, data from the current experiment identified 250 g straw per pig per day as the amount of straw where a further increase in straw provision did not further increase neither time spent on oral manipulation of straw, nor the percentage of pigs simultaneously manipulating straw. This suggests that, within the current housing system and using this criterion, this amount of straw may be the biological turning point for increasing oral manipulation of straw.
