Undocked Pigs Research Articles

Prevalence of tail damage and ear lesions in docked and undocked pigs during trials to find alternatives to tail docking on Spanish commercial farms.

Tail docking is widely used to control tail biting in pigs, but it is a painful and stressful procedure. The impact of non-docking trials on tail damage (TD) and ear lesions (EL) from weaning to slaughter was assessed on four commercial farms. A total of 898 docked pigs (396 DP) or undocked pigs (502 UP) were assessed for tail damage and ear lesions at the beginning and end of the weaner stage, during fattening and at the abattoir during slaughter. The percentage of UP with shortened tails increased significantly from weaning to fattening, but the percentage of non-inflamed tails and tails without fresh lesions increased. In terms of severity of lesion, a lower percentage of pigs scored as 'no visible lesion' at the end of weaning compared to fattening, both for UP and DP (p<0.05). DP always had a lower percentage of TD, whereas UP had a lower percentage of EL at the end of weaning. It was not possible to statistically compare different preventive strategies trialed on farms as alternatives to docking. This study highlights that combining tail length and lesion score at slaughter could be a reliable on-farm welfare indicator.

Amino acid supplementation counteracts negative effects of low protein diets on tail biting in pigs more than extra environmental enrichment

Low protein (LP) diets may increase the occurrence of damaging behaviours, like tail biting, in pigs. We investigated the effect of supplementing a LP diet with indispensable amino acids (IAA) or environmental enrichment on tail biting. Undocked pigs (n = 48 groups of 12) received either a normal protein diet (NP), a LP, LP with supplemented IAA (LP+), or LP diet with extra environmental enrichment (LP-E+) during the starter, grower, and finisher phase. Performance, activity, behaviour, and body damage were recorded. LP and LP-E+ had a lower feed intake, growth, and gain-to-feed ratio, and were more active than NP and LP+ pigs. LP-E+ pigs interacted most often with enrichment materials, followed by LP, LP+, and NP pigs. LP pigs showed more tail biting than all other groups during the starter phase and the finisher phase (tendency) compared to NP and LP+ pigs. Thus, LP-E+ only reduced tail biting in the starter phase, whereas LP+ tended to do so throughout. Tail damage was more severe in LP pigs than in NP and LP+, with LP-E+ in between. In conclusion, IAA supplementation was more effective than extra environmental enrichment in countering the negative effects of a low protein diet on tail biting in pigs.

Social interactions, precursors of damaging behaviours, object manipulation, straw rooting, and activity: a detailed data set in undocked pigs under protein restriction

Damaging behaviours, such as tail biting, are common problems in pig production, compromising animal welfare and causing economic losses. Detailed studies are impeded by laborious direct observations. Tail biting is a broader phenomenon that begins long before lesions manifest, and behavioural problems caused by various stressors present themselves weeks before they escalate to damaging behaviour. Therefore, we collected detailed data on behaviours considered precursors to tail biting, such as oral and nasal manipulation of conspecifics. Dietary protein reduction is a promising way to reduce nitrogen emissions in pig manure, but its implications for animal welfare are not yet clear. The CP content in the diet was reduced to 80% of the recommendations. Pigs differ in their ability to utilise dietary proteins; therefore, there might be individual differences in how they cope with the protein reduction. Here, we present detailed data of focal observations of 95 pigs at an experimental farm with undocked tails. Pigs were observed directly by the same person for five minutes on four different days. All actions directed towards objects in the pen, interactions with and confrontations among pen mates, straw rooting behaviour and general activity were recorded. After the behavioural observations, wounds on different body parts and the cleanliness were noted by the same person observing the pigs. The protein efficiency of 94 pigs was obtained. The data set comprises six tables. The first table contains information on the animals, including the identities of their parents, farrowing group, sex, and protein efficiency. The other data tables contain four 5-min observations of each pig on 10 object-manipulation behaviours; 150 interaction behaviours, including reactions; 14 confrontation behaviours and their outcomes and reactions; 10 mounting behaviours, including reactions; two rooting behaviours; seven basic behaviours; and an index of general activity. The observations took place under comparatively good housing conditions. Pigs were given fresh straw daily, ad libitum access to feed, floor space above the legal requirements, and daily cleaning of pens, and they were closely monitored for signs of damaging behaviour; all of these are favourable conditions as they limit stress and the risk of damaging behaviour. These data can be used to further explore the relationships of specific behaviours and phenomena and their association with protein efficiency. The ethogram can be used as a template for further observations. Practitioners could use the data to support pigs’ need for occupation, such as by providing sufficient straw.

Effects of improved early-life conditions on health, welfare, and performance of pigs raised on a conventional farm

Nowadays, most pigs are raised indoors, on intensive farms providing a poor environment. In these conditions, the risk of the occurrence of damaging behaviours is high, with dramatic consequences for animal health and welfare as well as economic losses for farmers. Early-life conditions may predispose individuals to develop damaging behaviours later in life. In contrast, reinforcing affiliative behaviours between piglets before weaning might help to prevent tail-biting episodes. In this field study, we aimed at improving early-life conditions of piglets on a commercial farm by completely suppressing painful procedures and staggering their exposure to weaning stress factors. The alternative early-life management strategy combined housing in free-farrowing pens with temporary crating of the sow, socialisation during the lactation period with whole-life maintenance of the hierarchical groups, and delayed transfer to the postweaning room after sow removal. Control conditions included birth in farrowing crates, tail docking, absence of socialisation during the lactation period, abrupt weaning with immediate transfer to the postweaning room and mixing with non-littermates. We evaluated the health, welfare, and performance of alternatively raised pigs (n = 80) as compared to controls (n = 75). Visits were made throughout the lifespan of individuals to evaluate their growth and health status. Body and tail lesions were scored as proxy measures of aggressiveness and impaired welfare. Blood and bristle samples were periodically collected to evaluate stress, inflammation and immune competence. While the whole-life performance of pigs was similar among groups, the alternative early-life conditions prevented the growth slowdown usually observed after weaning. In addition, alternatively raised pigs displayed more neutrophils, eosinophils and monocytes the day after weaning, as well as higher C-Reactive Protein levels. One week later, their monocytes displayed greater phagocytic capacity. Altogether, these data suggest an enhanced innate immune competence for alternatively raised pigs around weaning. Piglets reared under alternative conditions also exhibited fewer and less severe body lesions than standard pigs, one week after weaning. In contrast, they showed more tail lesions on days 36 and 66 associated with greater levels of acute phase proteins (C-Reactive Protein and haptoglobin). To conclude, alternative early-life management better prepared piglets for weaning. However, the whole-life maintenance of early-established social groups was not sufficient to prevent the occurrence of damaging behaviours in undocked pigs.

Undocked Tails, Mycoplasma-like Lesions and Gastric Ulcers in Slaughtering Pigs: What Connection?

Tail biting is an economical and behavioral problem in the pork production system worldwide and systematic tail docking has been applied for decades to decrease the risk of its onset. However, legal and market-driven requirements are leading pig producers to rear undocked animals. The aim of this work was to monitor tail, pluck (lungs, pleurae, and liver), stomach, carcass, and thigh lesions in slaughtering pigs belonging to either docked or undocked batches. A total of 525 batches were evaluated at slaughter: 442 docked and 83 undocked batches. The presence of tail lesions was only recorded in undocked batches (44.0 ± 0.402 vs. 0.2 ± 0.2% compared to docked ones, p &lt; 0.001), with a prevalence of severe chronic lesions of 27.3% ± 0.032, suggesting that more and alternative wide efforts to manage long-tailed animals are needed. On the contrary, docked animals showed more frequent ear lesions (9.6% ± 0.037 vs. 4.6% ± 0.019; p = 0.0001). Severe lung lesions were found more frequently in undocked animals (9.2% ± 0.043 vs. 6.6% ± 0.011, p = 0.006), as well as gastric ulcers (26.1% ± 0.021 vs. 20.3% ± 0.37, p = 0.006). These lesions might share the same predisposing factors of tail lesions; the latter might be investigated as an iceberg indicator for other pathological conditions in undocked pigs and eventual causal association among lesions in these organs should be explored.

Investigating the Reward Cycle of Play in Pigs (Sus scrofa)

Observations of play in animals have been suggested as a promising indicator of positive emotions and thus of positive animal welfare. However, if play can follow the proposed reward cycle concept where animals estimate and value reward differently in different phases of the cycle (anticipation, consummation and post-consummation) is unclear. To investigate if a reward cycle for play exists in growing pigs, we carried out an exploratory study where pigs were tested when they were naïve to a reward cycle test (first occasion) against when they were accustomed to going through the test after having the access to an open play arena with objects. Forty undocked pigs were housed in a weaner stable with two castrated males and two females per pen. Within each litter, we randomly selected and tested one male and one female test pig, each being tested as naïve or accustomed to the testing environment. The first week the pigs (n= 20) were tested four times and regarded as naïve during the first day. After that they were regarded as accustomed, and were tested twice a week for 3 weeks. We observed the behavior of the tested pairs in three subsequent stages: (1) in a holding pen 3 min, (2) in a play arena 15 min, and (3) in their home pen 10 min. When accustomed, pigs showed more locomotor play, social interactions and standing, and a tendency of more orientation toward the play arena and exploring bars facing the play arena (i.e., reward-seeking behavior) in the holding pen than when they were naïve, suggesting an anticipation to enter the play arena. Performing high numbers of object play in all sessions, and for accustomed pigs more exploration and social interaction, but less locomotor play and walking in the play arena may suggest consumption of play and exploration. Finding more lying and sitting in accustomed pigs, but less standing and walking in the home pen is in line with the previous hypothesis of the post-consummatory behaviors. Our study showed mixed results for the existence of a reward cycle for play in pigs and generated questions for future research.

Network analysis of tail-biting in pigs – indirect effect on tail posture

Tail-biting in pigs compromises animal health and animal welfare, thus, early indicators of an outbreak must be discovered before severe tail lesions occur. Tail posture is one of these promising indicators. The individual animal's behaviour is affected by the group structure, which can be investigated using social networks. Therefore, this study analysed the effect of the group structure of tail-biting pigs on tail posture using pig-level social network parameters. Detailed behavioural observations of 6 pens with 24 undocked pigs per pen four days before a tail-biting outbreak were the data basis. The effect of ingoing network parameters (weighted in-degree, weighted ingoing closeness) on binary tail posture (0: raised, 1: lowered) was tested as covariates in generalised linear mixed models. The pen (1-6), day (t-1 to t-4), hour (10:00 h – 17:00 h), location (at the trough, not at the trough) and receiver (received tail-directed behaviour in the previous 20 min, received no tail-directed behaviour in the previous 20 min) were used as fixed effects. Additional to the fixed effect receiver (p < 0.05), the probability of a lowered tail posture increased with higher values of weighted in-degree (p < 0.05) if less than 40 min passed between the tail-biting and the tail posture observation. If the tail-biting event was 40 to 120 min before the tail posture observation, the probability of a lowered tail posture increased with higher values of weighted ingoing closeness (p < 0.05). Furthermore, the location in the pen (p < 0.05) and the interaction between pen and day (p < 0.05) affected the tail posture significantly. Thus, the group structure of tail-biting pigs has a prolonged influence on tail posture. For this reason, the tail posture is a practicable indicator of tail-biting if monitored regularly.

Effects of Different Housing Systems during Suckling and Rearing Period on Skin and Tail Lesions, Tail Losses and Performance of Growing and Finishing Pigs.

Feasible alternatives to stressful weaning and tail-docking are needed to inhibit tail biting. Therefore, we investigated the effects of housing systems for 1106 pigs that were weaned from: (1) conventional farrowing crates (FC), (2) free-farrowing pens (FF), or (3) group housing of lactating sows (GH) into (1) conventional rearing pens (Conv) or (2) piglets remained in their farrowing pens for rearing (Reaf). Tails were docked or left undocked batchwise. All pigs were regrouped for the fattening period. Pigs were scored for skin lesions, tail lesions and losses. After weaning, Conv-GH pigs had significantly less skin lesions than Conv-FC and Conv-FF pigs. After regrouping for fattening, Reaf-GH pigs had significantly less skin lesions than Conv pigs, Reaf-FC and Reaf-FF. The frequency of tail lesions of undocked Conv pigs peaked in week 4 (66.8%). Two weeks later, Reaf undocked pigs reached their maximum (36.2%). At the end of fattening, 99.3% of undocked Conv pigs and 43.1% of undocked Reaf pigs lost parts of their tail. In conclusion, the co-mingling of piglets during suckling reduced the incidence of skin lesions. Rearing in the farrowing pen significantly reduced the incidence of tail lesions and losses for undocked pigs. No housing system negatively affected the performance.

Tasty straw pellets – Exploration of flavoured rooting material by pigs

Tail biting is a common problem in pigs kept in conventional fully slatted pens. Suitable enrichment materials can help to prevent the occurrence of this behavioural disorder by encouraging pigs to increase exploration behaviour. We investigated whether additional flavours can increase exploration behaviour in undocked pigs. Therefore, we offered straw pellets flavoured with either fried onion (FO), strawberry (SB), ginger, almond (AL), vanilla or without flavour (control) during rearing (eight groups in total) and fattening (16 groups in total). Flavoured pellets were offered in an altering order during intervals of 1 week in material dispensers. Exploration duration at the material dispensers was continuously recorded via an ultra-high-frequency radio-frequency identification system. Pigs were weighed weekly and their tail lengths and tail injuries were scored in four categories. For analysis, changes in tail length scores compared to the previous week were calculated as Δ-tail length. The different flavours affected pigs’ exploration durations in both rearing (factor flavour, P < 0.0001) and fattening (factor flavour, P < 0.0001). Highest exploration durations during rearing were recorded when straw pellets were flavoured with FO and AL compared to all others. During fattening, exploration duration was highest towards controls without significant difference to SB. Exploration durations additionally were affected by temporal effects, i.e. week and day during rearing (both factors: P < 0.0001) and fattening (both factors: P < 0.0001). During rearing, highest exploration durations were recorded in the first week and on the first day within week after changing the flavour of the straw pellets. During fattening, exploration durations varied between weeks and within weeks. The highest durations were recorded at the end of weeks, i.e. on the fifth and seventh days after material change. During rearing, tail injuries were affected by week (P < 0.0001). From the fourth week of rearing, the prevalence of tail injuries significantly increased. During the fattening period, tail injuries were affected by flavour (P < 0.05). Fattening pigs had fewest tail injuries after straw pellets flavoured with AL were offered. Altogether, based on the exploration durations, rearing pigs showed different preferences for the flavoured straw pellets but highly explored flavours differed between rearing and fattening pigs. Despite a weekly change of the flavour of straw pellets, exploration durations decreased during rearing but increased again in the transition between rearing and fattening. Thus, straw pellets with alternating flavours are a suitable possibility to provide environmental enrichment to pigs but will not prevent tail biting.

Effect of plant-based enrichment materials on exploration in rearing and fattening pigs (Sus scrofa domesticus)

When pigs cannot perform innate species-specific behaviours (e.g. rooting or chewing), behavioural disorders, like tail biting, can occur. However, it seems that various enrichment materials enhance the pigs to perform exploration behaviour and therefore can help to reduce and prevent tail biting. The aim of this study was to identify such highly explored plant-based enrichment material for undocked pigs during rearing and fattening. Furthermore, we evaluated the impact of the offered enrichment materials on tail length and injuries. Therefore, we continuously recorded the individuals’ exploration durations in 20 groups by using an ultra-high-frequency radio-frequency identification system, installed at material dispensers. Lucerne pellets (LP), straw pellets (SP), chopped hay (CH) and chopped straw (CS) were offered in a systematically alternating order for two-week sections, respectively. At weaning and at days of material change (i.e. eight times in total), animals were weighed and scored for tail length losses and tail injuries. For analysis, the changes in tail length compared to the previous section were calculated as Δ-tail-length losses. Our study revealed that the different offered plant-based enrichment materials affected the duration of exploration behaviour (e.g. rooting, nosing or chewing) during rearing (4 groups, LME, p < 0.0001) and fattening (16 groups, LME, p < 0.0001). In piglets, exploration duration was higher for pelletized materials (LP, SP) than for chopped materials. Fattening pigs explored materials of hay (CH) more often compared to straw-based materials (CS, SP). Daily weight gains of rearing pigs were affected by the type of enrichment material offered in the respective section (LME, p < 0.0001). The highest daily weight gains were achieved when CH was offered. Exploration duration during rearing and fattening was affected by section (LME, both p < 0.0001 for rearing and fattening). Exploration duration during rearing was highest in section 4 and continuously increased from the first section to the last section during fattening. During rearing, the plant-based enrichment materials affected tail injuries (GLMM, p < 0.0001) and Δ-tail-length losses tended to be affected (GLMM, p = 0.057). Fewest tail injuries and Δ-tail-length losses occurred when SP was offered. During fattening, section affected tail injuries (GLMM, p = 0.01). Most injuries occurred during sections 1 and 2. Our results show that pigs of different ages seem to prefer different plant-based enrichment materials. High exploration durations do not necessarily maintain intact tails if material is changed biweekly. However, exploration durations can be maintained at high levels from rearing through fattening period by regularly alternating the provided plant-based enrichment materials.

Effect of Straw Provision in Racks on Tail Lesions, Straw Availability, and Pen Hygiene in Finishing Pigs.

Simple SummaryPigs spend the majority of their time exploring their surroundings. Unfulfilled exploratory behavior has been linked to tail biting in pigs, leading to decreased welfare and production. Straw provision enables exploratory behavior and reduces tail biting, but large amounts of straw may be difficult to incorporate into current production systems, causing e.g., poor hygiene. This study examined whether provision of straw in racks, rather than on the floor, can enable larger straw rations without compromising hygiene. The study was conducted on a commercial farm with 458 undocked pigs in 42 pens provided with straw in racks or on the floor. Available straw and manual cleaning requirement were assessed daily, and presence of tail lesions was assessed weekly. Compared with pigs in the floor treatment, pigs in the rack treatment had more lesions in the beginning of the production period, but fewer tail lesions at the end. This could be because pigs in the rack treatment initially did not consume straw from the rack, leading to low straw access early in the production period.Unfulfilled exploratory behavior in pigs has been linked to tail biting, which causes reduced performance and welfare. Provision of straw can reduce tail biting, but large straw rations can cause poor hygiene in pens. This study examined whether provision of straw in racks, rather than on the pen floor, can enable larger straw rations without compromising hygiene. The study was conducted on a commercial farm with 458 undocked pigs in 42 pens provided with straw in racks or on the floor. Available straw and manual cleaning requirement were assessed daily, and presence of tail lesions was assessed weekly. Both treatments had a low requirement for manual cleaning (Floor: 1.7%, Rack: 1.8%). Pigs in the rack treatment had a higher incidence of lesions early in the production period, which coincided with these pigs initially not consuming straw from the rack, leading to low straw access. Late in the production period, these pigs had learned how to use the rack and had a lower incidence of lesions than pigs in the floor treatment. Delayed use of the rack may have been linked to undeveloped spatial skills in the pigs, which needs further research.

A High Enrichment Replenishment Rate Reduces Damaging Behaviors and Increases Growth Rate in Undocked Pigs Kept in Fully Slatted Pens.

One of the difficulties in complying with the prohibition of routine tail docking is a lack of effective alternative solutions to prevent tail biting, especially in fully slatted systems. This study compared three slat-compatible enrichment replenishment strategies for pigs. Forty-eight mixed-sex pens (six males and six females/pen) of undocked pigs were followed from birth to slaughter. Pre-weaning, half the pigs were provided with enrichment materials (a cardboard cup, rubber toy, hessian cloth and bamboo), in addition to a rope for the sows, in all farrowing crates. Post-weaning, all pens were enriched with eight identical items, including an elevated rack supplied with fresh-cut grass, and objects of wooden, bamboo, rubber, and fabric materials presented in various ways. However, three different replenishment frequencies were applied: “Low” (replenished on Monday/Wednesday/Friday), “Medium” (replenished once daily), and “High” (replenished ad libitum). Individual pigs were weighed on days 0, 49, 91, and 113 post-weaning. Direct behavior observations were conducted twice weekly at pen level (10 min/day/pen), and tail and ear lesion scores of individual pigs were also recorded every other week. These measurements were taken during the post-weaning period. The cost of all enrichment materials used was calculated. Pre-weaning enrichment only contributed to a lower ear lesion score (P = 0.04). No difference in lesion scores was found between post-weaning treatments. “Low” replenishment rate pigs performed more damaging behaviors (tail/ear biting, belly-nosing, mounting, other biting, and aggressive behaviors combined) than “High” and “Medium” pigs (P < 0.01). The average daily gain in the finishing stage was higher in “High” than “Low” pigs (P < 0.05). Although sporadic tail biting occurred, only 0.69% of the pigs had their tails bitten severely enough that they became shorter than half of a normal undocked tail. The average enrichment cost for the post-weaning period was <€2 per pig. In conclusion, the high enrichment replenishment rate increased growth and reduced damaging behaviors compared to the low replenishment rate pigs. Overall, these findings show that the provision and regular replenishment of multiple, slat-compatible, enrichment sources can reduce tail damage to manageable levels without the need for tail docking.

Risk factors for tail lesions in undocked fattening pigs reared on Swiss farms.

Tail lesions caused by tail biting are a major welfare and economic concern in fattening pigs. The aims of this study were to describe the prevalence and incidence of tail lesions in undocked pigs on individual animal level during the fattening period, to elucidate potential risk factors associated with tail lesions, and to describe the stockpersons' attitudes towards tail biting on Swiss farms. Thirty-eight farms were visited three times during the fattening period (beginning, mid-point, end). During each farm visit, tail lesions were scored on 30-126 individually marked pigs per farm (total: 2209 pigs), information on potential risk factors for tail lesions was recorded, and a standardized interview with the farmer was conducted to explore his/her opinion on tail biting. Potential risk factors were defined by indices when adequate, and their influence on the occurrence of tail lesions was analyzed using mixed effects logistic regression models. During the first and the second half of the fattening period, on average 14,1 and 15,4 pigs, respectively, out of 100 developed new tail lesions or aggravation of old lesions. The risk for new or aggravated tail lesions increased with higher scores for a «disease index» and with increasing group size, and it decreased with higher space allowances and with restrictive compared with ad libitum feeding. The prevalence of tail lesions on arrival was not associated with the incidence of tail lesions in the first and the second half of the fattening period, neither at farm level nor at pen level. In the interviews, farmers expressed their interest in getting professional advice on how to reduce tail biting on their farms. In conclusion, our study identified several risk factors for tail lesions in undocked fattening pigs indicating that the incidence of tail lesions could be reduced by improving animal health and housing conditions.

Can increased dietary fibre level and a single enrichment device reduce the risk of tail biting in undocked growing-finishing pigs in fully slatted systems?

This study evaluated the effectiveness of combined dietary and enrichment strategies to manage tail biting in pigs with intact tails in a conventional fully-slatted floor housing system. A 2 × 2 × 2 factorial design was used. Pigs had either a high fibre (weaner 5.3% and finisher 11.6% of crude fibre) or standard fibre diet (weaner 3.7% and finisher 5.9% of crude fibre). In the weaner stage, pigs had either a spruce wooden post (supplied in a wall-mounted dispenser) or a rubber floor toy as a enrichment device, and in the finisher stage, they had either the same or alternate enrichment item. Six hundred and seventy-two pigs were assigned to 48 pens of 14 pigs and followed from weaning until slaughter. Individual tail lesion scores and pen level behaviours were directly recorded every 2 weeks. Twenty-six pens had tail biting outbreaks and 161 injured pigs needed removal for treatment. Pigs fed with the high fibre diet performed more tail biting (p < 0.05) and tended to have a worse tail damage scores than those fed the standard fibre diet (p = 0.08). Pigs which had the floor toy as weaners and wood as finishers tended to have fewer tail lesions in the finisher stage than their counterparts (p = 0.06). Pigs receiving the floor toy as enrichment interacted with the enrichment more frequently overall (p < 0.001) and performed fewer harmful behaviours in the weaner stage (p < 0.05). Overall, higher fibre in the diet in a relatively barren environment did not help reduce tail biting or tail lesions. Altering the fibre level in the pigs' diet and providing a single enrichment device to undocked pigs on fully slatted floors resulted in a high level of tail biting and a large proportion of pigs with partial tail amputation.

Intact Tails as a Welfare Indicator in Finishing Pigs? Scoring of Tail Lesions and Defining Intact Tails in Undocked Pigs at the Abattoir.

Tail biting lesions are a potential measure of on-farm animal welfare, as a large range of stressors increase the risk for tail biting outbreaks. Further, tail biting is a major challenge, as lesions due to tail biting decrease animal welfare and health, as well as production efficiency and carcass quality. The aim of this study was to suggest a tail scoring system for use at slaughterhouses processing undocked pigs, and to link tail lesion scores to meat inspection data. A further aim was to suggest a definition for an intact enough tail. To validate the suggested scoring system we assessed tails before and after scalding and compared results to pathological examinations. In total, 14,433 tails were scored, and 117 tails were collected for pathological examination. After scalding, 49.2% of all tails were scored as fully intact. Of tails with lesions 2.5% were scored as having major acute wounds (>2 cm), while 11.6% had minor acute wounds (<2 cm), and 36.7% healed lesions. Intact tails were on average 31.5 cm (SD 2.5 cm) long. Lesion scored at the slaughter-line agreed well with the pathological assessment. Tail lesions were associated with several meat inspection findings: tails with more severe lesions and of shorter length increased the risk for meat inspection findings to a higher degree. A detailed lesion scoring method helps to identify carcasses at risk for condemnations, as well as being a potential method for on-farm welfare estimation. We suggest that a system for scoring tail lesions in undocked pigs should utilize a combination of scoring of the lesion and measuring the tail length. As bite marks or bruises on an otherwise intact tail were not a concern for meat hygiene, we suggest the definition of an intact enough tail could allow the inclusion of tails with these mild changes. Meat inspection findings in carcasses with tails scored as healed, but with no fresh lesions, and with more than 75% of the average intact length remaining were rather similar to those of fully intact tails. Based on these findings we suggest that a tail of this length, and with no visible fresh lesions could also be considered intact enough.

Tail and ear postures of growing pigs in two different housing conditions

This study analyses tail and ear postures of growing pigs in two different housing systems throughout the growing period. On one farm, 168 undocked pigs (84: barren housing, 84: enriched housing) were observed individually at three time periods: beginning, middle and end of the growing period. By scan sampling, the tail (curled-up, raised, hanging, tucked under, wagging) and ear posture (forwards, sidewards, backwards, mixed) was noted. Scans were performed hourly during the activity periods by direct observation. Moreover, the body posture (standing, feeding, lying (eyes open), lying (eyes closed) and tail lesions were noted. Data were analysed using the GLIMMIX procedure in SAS. Results revealed significant differences between the enriched and barren group especially for curled-up tails, tucked under tails and ears directed forwards. More curled-up tails and ears directed forwards occurred in the enriched and more tucked under tails in the barren habitat. The time period of observation also had significant influences. Tail lesions had significant effects on most tail postures. Most ear postures were influenced by the body posture of the pigs. Overall, this study contributes to the understanding of body language, specifically tail and ear postures in pigs.

Tail Lesions and Losses of Docked and Undocked Pigs in Different Farrowing and Rearing Systems

This study aimed to investigate the effects of farrowing and rearing systems on tail lesions and losses of docked and undocked pigs. Pigs from three farrowing systems: Conventional farrowing crate (FC), free farrowing (FF) and group housing of lactating sows (GH) were randomly allocated to different rearing systems: A conventional system (CONV), where the pigs were regrouped and transferred to conventional finishing pens at ten weeks of age or a wean-to-finish (W-F) system, where the pigs remained in their pens until slaughter with higher space allowance during rearing. Weekly, tail lesions and losses were assessed individually. The incidence of tail lesions was higher in undocked CONV pigs compared to undocked W-F pigs (maximum: CONV 58.01%, W-F 41.16%). The rearing system had a significant effect on tail losses at the end of finishing (CONV 67.63%, W-F 38.2%). The significant effect of the rearing system might be explained by higher space allowance during rearing and reduced regrouping stress for W-F pigs. In conclusion, farrowing systems showed no effects, but the W-F rearing system reduces the frequency of tail lesions and losses; the curves of tail lesions increased slower and stayed on a lower level, which resulted in lower losses as well.

Influence on tail-biting in weaning pigs of crude fibre content and different crude fibre components in pigs' rations

AbstractThe aim of the study was to analyse the influence on tail-biting in undocked pigs during the rearing period of crude fibre in piglets' rations. All pigs were fed the same pre-starter until weaning. The study comprised two trials with four experimental groups each. The first trial contained: a control group (CG1) with conventional feed (up to 40 g/kg crude fibre), two groups with an increased crude fibre content of up to 50 g/kg (G5) and 60 g/kg (G6), respectively, and one group with conventional feed and crude fibre provision ad libitum (AL). The second trial consisted of a control group (CG2) which received the same conventional feed as CG1 and three treatment groups with either soya hulls (SS), dried sugar beet pulp (DP) or oat fibre (OF) admixed to their ration, to achieve a crude fibre content of 60 g/kg in all three groups. The rearing week, the batch, the treatment group (only in trial one) and the interaction between batch and treatment group had a significant influence on tail-lesions (P &lt; 0.05). The tail-biting process started in rearing week 3 (trial one) and 5 (trial two), respectively. Due to the low frequency of tail-biting during the present study, crude fibre seems to have no major influence on tail-biting during the rearing period. This unexpected result may be caused by the optimized conditions in which the piglets were kept and the intensive animal observation carried out by the employees. However, the batch effect was most influential.

Antimicrobial use on Italian Pig Farms and its Relationship with Husbandry Practices.

Simple SummaryQuantifying antimicrobial use (AMU) in livestock using dose-based methods is useful for identifying potential risk factors related to AMU and to promote responsible AMU. Herewith, we investigated the temporal patterns and effects of several structural and management factors on AMU in a sample of pig farms in northern Italy during a period of three years. Overall, AMU showed a large variability between farms and no significantly decreasing trend. However, in several farms, a significant AMU reduction of up to two-thirds was observed. Farm size, number of farm workers, air quality, average pig mortality, and presence of pigs with undocked tails on the farm had no significant effect on AMU, whereas higher welfare standards were significantly associated with lower AMU. The analysis of antimicrobial use (AMU) data in livestock allows for the identification of risk factors for AMU, thereby favoring the application of responsible AMU policies on-farm. Herewith, AMU in 36 finishing pig farms in northern Italy from 2015–2017 was expressed as defined daily doses for Italian pigs (DDDita) per population correction unit (DDDita/100kg). A retrospective analysis was then conducted to determine the effects of several husbandry practices on AMU. Overall, AMU ranged between 12 DDDita/100kg in 2015 and 8 DDDita/100kg in 2017, showing no significant trends, due to the large variability in AMU between farms. However, a 66% AMU reduction was observed in 19 farms during 2015-2017. Farm size, number of farm workers, air quality, average pig mortality, and presence of undocked pigs on the farm had no significant effects on AMU. Rather, welfare-friendly farms had 38% lower AMU levels (p < 0.05). In conclusion, animal welfare management seems to be relatively more important than farm structure and other managerial characteristics as drivers of AMU in finishing pig farms.

Rearing Pigs with Intact Tails-Experiences and Practical Solutions in Sweden.

Tail biting is a common issue within commercial pig production. It is mainly an indicator of inadequate housing environment and results in reduced health welfare and production. To reduce the impact of tail biting, pigs are commonly tail docked, without pain relief, within the first week of life. EU Council Directive 2008/120/EC prohibits routine tail docking, but the practice is still widely used in many Member States. Sweden has banned tail docking since 1988 and all pigs have intact tails, yet tail biting is a minor problem. This paper summarises and synthesises experimental findings and practical expertise in production of undocked pigs in Sweden and describes solutions to facilitate a transition to producing pigs with intact tails within intensive pig production in the EU. Swedish pig housing conditions and management differ in many aspects from those in other EU Member States. Swedish experiences show that lower stocking density, provision of sufficient feeding space, no fully slatted flooring, strict maximum levels for noxious gases and regular provision of litter material are crucial for success when rearing pigs with intact tails. To prevent tail biting and to eliminate the need for tail docking, we strongly recommend that EU legislation should more clearly match the biological needs of pigs, as is done in Swedish legislation.