Category Archives: Health

Reducing crude protein levels in pig diets to increase protein efficiency may also increase damaging behaviours, esp. under conditions of poor sanitation

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.

Ice blocks may vaccinate and enrich gestating sow welfare

An investigation of sow interaction with ice blocks on a farm with group-housed sows fed by electronic sow feeders

By M.K. Pierdon, A.M. John and T.D. Parsons. in: Journal of Swine Health and Production 24(6):309-314 · November 2016


More gestating sows are being housed in pens where it is challenging to implement controlled exposure to pathogens for disease control (“feedback”). Ice blocks provide a possible vehicle for feedback material in pen gestation. Ice blocks were placed once weekly for 6 consecutive weeks in a pen of approximately 130 sows to test whether sows would interact with the blocks of ice. Sows were housed in a large, dynamic pre-implantation group fed with electronic sow feeders. Each ice block was video-recorded for 1 hour. All sows that contacted it were identified. The number of sows, their duration of contact, and amount of aggression were coded from the video. Median number of sows that interacted with the ice was 94, and increasing the number of ice blocks from two to four per pen increased the median number of sows to contact the ice and the median duration of an individual sow’s contact with the ice, and decreased the amount of aggression at each block. Our findings suggest ice blocks are a convenient vehicle for controlled exposure of feedback material to gestating sows housed in large pens. However, additional studies are needed to validate pathogen exposure with this method.


Understanding tail biters and victimized pigs during outbreaks of tail biting

Understanding tail biters and victimized pigs during outbreaks of tail biting
By Y. Li, J. Anderson, A. Holten, A.M. Hilbrands, J. Holen and L.J. Johnston, 2016. Jounal of Animal Science 94, suppl 2: 2, p. 8-9.


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.

Impact of straw on gastric ulceration in pigs

Impact of the amount of straw provided to pigs kept in intensive production conditions on the occurrence and severity of gastric ulceration at slaughter.
Herskin MS, Jensen HE, Jespersen A, Forkman B, Jensen MB, Canibe N, Pedersen LJ. 2016. Res Vet Sci. 104: 200-6.


This study examined effects of the amount of straw offered on occurrence and severity of gastric lesions in pigs kept in pens (18 pigs, 0.7m(2)/pig) with partly slatted flooring and 10, 500 or 1000g straw/pig/day from 30kg live weight. The pigs had ad libitum access to dry feed. Forty-five pigs were used, three from each of 15 pens. After euthanisia, the dimension of the non-glandular region of the stomach was measured. Lesions were characterized and scored. Irrespective of straw provided, 67% of the pigs showed signs of gastric pathology. Pigs provided with 500 or 1000g straw were pooled as ‘permanent access’. The proportion of pigs with ulcerations was reduced by permanent access to straw (7 vs. 33%; P<0.05), suggesting that permanent access to straw may improve animal health, and be considered as one possible strategy to limit gastric ulceration in pigs.

500gr straw/pig/day
500gr straw/pig/day
10gr straw/pig/day
10gr straw/pig/day

Penile injuries (incl. penis biting) in domestic (& wild) pigs

Penile Injuries in Wild and Domestic Pigs.
By Weiler U, Isernhagen M, Stefanski V, Ritzmann M, Kress K, Hein C, Zöls S. 2016. Animals 6: 4.


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.

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.

Study on the Association between Tail Lesion Score, Cold Carcass Weight, and Viscera Condemnations in Slaughter Pigs

Study on the Association between Tail Lesion Score, Cold Carcass Weight, and Viscera Condemnations in Slaughter Pigs
By Dayane L.Teixeira, Sarah Harley, Alison Hanlon, Niamh Elizabeth O’Connell, Simon J. More, Edgar G. Manzanilla and Laura A. Boyle, 2016. Frontiers in Veterinary Science.


The aim of this study was to assess the relationship between tail lesions, cold carcass weight, and viscera condemnations in an Irish abattoir. The following data were collected at the evisceration point from every third pig slaughtered over 7 days: farm identification, sex, tail lesion score, viscera inspection outcome, and cold carcass weight. Tail lesions were scored according to a 5-point scale. Disease lesions responsible for lung (pleurisy, pneumonia, and abscess), heart (pericarditis), and liver (ascariasis) condemnation were recorded based on the decision of the veterinary inspector (VI). Data on 3,143 pigs from 61 batches were available. The relationship between disease lesions, tail lesion score, and cold carcass weight was studied at individual carcass level, while the relationship between disease lesions and tail lesion score was studied at both carcass and batch level. Tail lesions (score ≥1) were found in 72% of the study population, with 2.3% affected by severe tail lesions (scores ≥3). Pleurisy (13.7%) followed by pneumonia (10.4%) showed the highest prevalence, whereas the prevalence of ascariasis showed the greatest variation between batches (0-75%). Tail lesion score, pleurisy, pleuropneumonia, and pericarditis were associated with reductions in carcass cold weight (P ≤ 0.05) ranging from 3 to 6.6 kg. Tail lesion score was associated with condemnations for pleurisy, pneumonia, and pleuropneumonia (P ≤ 0.05) at a batch level. VI shift was associated with condemnations for pneumonia, pleuropneumonia, and pericarditis (P ≤ 0.05) at a carcass level and with pneumonia at a batch level. Sex was not associated with viscera condemnations but males were more likely to be affected by tail lesions. The relationship between overall tail lesion score and the lung diseases at batch level supports the relationship between poor health and poor welfare of pigs on farms. The inclusion of tail lesion scores at post-mortem meat inspection should be considered as a health and welfare diagnostic tool.

Effects of clinical lameness and tail biting lesions on voluntary feed intake in growing pigs

Effects of clinical lameness and tail biting lesions on voluntary feed intake in growing pigs
Camilla Munsterhjelm, Mari Heinonen and Anna Valros, 2015. Livestock Science, 181: 210–219.


• We modelled voluntary feed intake in clinically lame or tail bitten pigs.
• Age, sex, diagnosis, initial weight and eventual recovery affects feed intake.
• Feed intake starts decreasing 2–3 weeks before diagnosis.
• Feed intake decreases 10–99% from control levels in sick pigs.
• Anorexia is prolonged in lame animals not recovering to slaughter condition.


A decreased feed intake is considered one of the first signs of disease in farm animals. Feeding-related individual data collected by electronic feeding systems may thus be useful in detecting illness at an early stage. The aim of this study was to determine changes in individual-level voluntary feed intake in growing pigs before and after a bout of sickness modelled by clinical lameness or an acute tail (biting) lesion, which together count for a significant part of overall health problems in intensive pig production. The data consisted of individual records of health and day-level feed intake in fattening pigs between about 40 and 120 kg obtained from the Finnish progeny test farm. Feed was available ad libitum from automatic single-space feeders. Two time periods in relation to diagnosis (day 0), day −50 to 0 (pre-) and day 0 to +50 (post-), were modelled separately for both diagnoses using hierarchical linear models with random and repeated effects. All healthy animals in the affected animals’ pens were used as controls. The number of pigs in the different analyses were 243/551 (cases/controls, pre-tail lesion), 205/693 (post-tail lesion), 116/588 (pre-lameness) and 165/892 (post-lameness).
Feed intake in the study animals was affected by sex, weight at arrival to the farm, health status (lame or tail bitten case vs healthy control), eventual recovery (culled or dead vs recovering to slaughter condition), the day relative to diagnosis and approximate age (the day on the farm), with the four latter factors involved in multiple interactions. Feed intake started decreasing already 2–3 weeks pre-diagnosis in future lame or tail bitten animals, suggesting a common predisposing factor such as reactive coping. Feed intake decreased substantially (13–99%) from control levels in sick animals, with the level dependent on diagnosis, degree of eventual recovery and age. Lame animals ingested two to three times less than tail bitten ones at diagnosis. Within both diagnoses, culled-to-be animals ingested roughly half the relative amount of those recovering to slaughter condition, suggesting that relative feed intake at diagnosis may predict the outcome of disease. Younger animals were generally more severely affected than older ones. Anorexia was prolonged up to about 30 days in culled-to-be lame animals in contrast to all other groups modeled, which started recovery immediately upon diagnosis and initiated treatment. The observed changes and differences in feed intake may indicate differences in animal welfare.

Saving the pig tail

Anna Valros and Mari Heinonen published a paper called “Save the pig tail” in Porcine Health Management.


Tail biting is a common problem in modern pig production and has a negative impact on both animal welfare and economic result of the farm. Tail biting risk is increased by management and housing practices that fail to meet the basic needs of pigs. Tail docking is commonly used to reduce the risk of tail biting, but tail docking in itself is a welfare problem, as it causes pain to the pigs, and facilitates suboptimal production methods from a welfare point-of-view. When evaluating the cost and benefit of tail docking, it is important to consider negative impacts of both tail docking and tail biting. It is also essential to realize that even though 100% of the pigs are normally docked, only a minority will end up bitten, even in the worst case. In addition, data suggests that tail biting can be managed to an acceptable level even without tail docking, by correcting the production system to better meet the basic needs of the pigs.

Valros, A., M. Heinonen, 2015. Save the pig tail. Porcine Health Management 2015 1:2.

Project objectives

FareWellDock project: aim and objectives

FareWellDock is a three-year research project which is part of the Animal Health and Welfare (ANIHWA) ERA-net initiative. The ANIHWA ERA-Net aims to increase cooperation and coordination of national research programmes on the health and welfare of farm animals.

The general aim of the FareWellDock project is to supply necessary information for quantitative risk assessment and stimulate the development towards a non-docking policy in the EU.

The project is led by Professor Anna Valros at the University of Helsinki. The other partners in the project include Scotland’s Rural College (SRUC), Newcastle University, INRA (France), Aarhus University (Denmark), Wageningen UR Livestock Research (Netherlands), SLU (Sweden) and the Norwegian School of Veterinary Science.

The research concerns the hazards related to using tail docking as a preventive measure in comparison with the hazard of being tail bitten, as well as on solving some of the main risk factors of tail biting: lack of enrichment, health problems, and delayed detection of an outbreak. In particular new animal-based measures are studied for a better comprehension of the consequences and the prevention of tail docking and tail biting, for enrichment value assessment, and for pain and sickness diagnostics. In addition to aiding future risk assessment, this project provides information about how end users (esp. farmers) can reduce tail biting.

The project has 3 work packages (WP). WP1 concerns pain related to docking and tail biting; WP2 concerns enrichment, and WP 3 concerns health and behaviour-related predispositions to tail biting. The WPs are coordinated by Newcastle University, Aarhus University and the University of Helsinki respectively.

The objectives of WP1 are:
* To characterise the time course of traumatic neuroma development caused by tail resection.
* To assess 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. At a more fundamental level, this provides a model of the effects of nerve damage (amputation) in neonates, subsequent neuroma development and its effects upon nociceptive processing throughout life.
* To assess the effects of tail-damage in more mature pigs on neuroma formation and stump pain sensitivity. This will provide a basis for assessing the pain associated with being tail

The objectives of WP2 are:
* To develop and validate a protocol for an animal-based screening method, based on exploratory behaviour and skin/tail lesions, for what constitutes a sufficient quantity of rooting material.
* To explore the feasibility and validity of using AMI sensors and tear staining to measure the value of enrichment materials under farm conditions.
* To test the effect of straw length, slat width and manure handling methods on pen functioning and ease of manure handling, and to describe suitable methods for implementing use of straw under commercial farming conditions.
* To make scientific information on methods to reduce tail docking and improve enrichment better accessible to farmers, policy makers and the general public through the establishment of a web tool and publications in farmer magazines.
* To investigate, under farm conditions, the efficiency of tail docking vs. enrichment given in sufficient quantity to reduce the occurrence of tail lesions.

The objectives of WP3 are:
* To clarify the role of poor health in the causation of tail biting and victimization. Information will be gathered on behavioural signs of sickness in pigs, and on its effects on group dynamics
* To increase knowledge about the sickness behavior of pigs suffering from different physical injuries and infectious conditions, occurring also in tail biting outbreaks. This in turn can be used when management and facilities for sick pigs are planned in the future, to decrease the adverse effects of such outbreaks
* To study the underlying central and peripheral stress- and immune-related mechanisms in detail to give insight into factors predisposing pigs to become tail biters or victims.
* To determine the characteristics of individuals for reliable identification of pigs at risk of becoming a tail biter or victim, including tail-biting related and social behaviour, and tear staining
* To develop automated systems for early warning of tail biting outbreaks which could be used especially in large herds

Project activities related to communication include the the writing of scientific papers, giving presentations at meetings/conferences, the production of webpages, blog posts and factsheets on this website, and providing input for farmer magazines.

Figure 1 of the FareWellDock project
Figure 1 Structure of the FareWellDock project

See also:
New Project Aims to End Tail Docking.
Project summary of FareWellDock on the Eranet ANIHWA website.