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Docking the value of pigmeat? Prevalence and financial implications of welfare lesions in Irish slaughter pigs


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Expansion of the meat inspection process to incorporate animal-based welfare measurements could contribute towards significant improvements in pig (Sus scrofa domesticus) welfare and farm profitability. This study aimed to determine the prevalence of different welfare-related lesions on the carcase and their relationship with carcase condemnations (CC) and carcase weight (CW). The financial implications of losses associated with CC and CW reductions related to the welfare lesions were also estimated. Data on tail lesions, loin bruising and bursitis, CW and condemnation/trimming outcome (and associated weights) were collected for 3,537 slaughter pigs (mean [±SEM] carcase weight: 79.2 [± 8.82]kg). Overall, 72.5% of pigs had detectable tail lesions, whilst 16.0and 44.0% were affected by severe loin bruising and hind limb bursitis, respectively. There were 2.5% of study carcases condemned and a further 3.3% were trimmed. The primary cause of CC was abscessation. While tail lesion severity did not increase the risk of abscessation, it was significantly associated with CC. Male pigs had a higher risk of tail lesions and of CC. The financial loss to producers associated with CC and trimmings was estimated at €1.10 per study pig. CW was reduced by up to 12kg in cases of severe tail lesions. However, even mild lesions were associated with a significant reduction in CW of 1.2kg. The value of the loss in potential CW associated with tail lesions was €0.59 per study pig. Combined with losses attributable to CC and trimmings this represented a loss of 43% of the profit margin per pig, at the time of the study, attributable to tail biting. These findings illustrate the magnitude of the impact of tail biting on pig welfare and on profitability of the pig industry. They also emphasise the potential contribution that the inclusion of welfare param-eters at meat inspection could make to pig producers in informing herd health and welfare management plans.
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© 2014 Universities Federation for Animal Welfare
The Old School, Brewhouse Hill, Wheathampstead,
Hertfordshire AL4 8AN, UK
Animal Welfare 2014, 23: 275-285
ISSN 0962-7286
doi: 10.7120/09627286.23.3.275
Docking the value of pigmeat? Prevalence and financial implications of
welfare lesions in Irish slaughter pigs
S Harley, LA Boyle, NE O’Connell§, SJ More#, DL Teixeira*and A Hanlon#
School of Veterinary Science, University of Liverpool, Neston, Cheshire CH64 7TE, UK
Animal & Grassland Research & Innovation Centre, Teagasc Moorepark, Fermoy, Co Cork, Republic of Ireland
§Institute for Global Food Security, Northern Ireland Technology Centre, Queens University Belfast, Malone Road, Belfast BT9 5HN, UK
#UCD School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Republic of Ireland
* Contact for correspondence and requests for reprints:
Expansion of the meat inspection process to incorporate animal-based welfare measurements could contribute towards significant
improvements in pig (Sus scrofa domesticus) welfare and farm profitability. This study aimed to determine the prevalence of different
welfare-related lesions on the carcase and their relationship with carcase condemnations (CC) and carcase weight (CW). The financial
implications of losses associated with CC and CW reductions related to the welfare lesions were also estimated. Data on tail lesions,
loin bruising and bursitis, CW and condemnation/trimming outcome (and associated weights) were collected for 3,537 slaughter pigs
(mean [±SEM] carcase weight: 79.2 [± 8.82]kg). Overall, 72.5% of pigs had detectable tail lesions, whilst 16.0and 44.0% were
affected by severe loin bruising and hind limb bursitis, respectively. There were 2.5% of study carcases condemned and a further 3.3%
were trimmed. The primary cause of CC was abscessation. While tail lesion severity did not increase the risk of abscessation, it was
significantly associated with CC. Male pigs had a higher risk of tail lesions and of CC. The financial loss to producers associated with
CC and trimmings was estimated at 1.10 per study pig. CW was reduced by up to 12kg in cases of severe tail lesions. However,
even mild lesions were associated with a significant reduction in CW of 1.2kg. The value of the loss in potential CW associated with
tail lesions was 0.59 per study pig. Combined with losses attributable to CC and trimmings this represented a loss of 43% of the profit
margin per pig, at the time of the study, attributable to tail biting. These findings illustrate the magnitude of the impact of tail biting
on pig welfare and on profitability of the pig industry. They also emphasise the potential contribution that the inclusion of welfare param-
eters at meat inspection could make to pig producers in informing herd health and welfare management plans.
Keywords:animal welfare, carcase, economics, meat inspection, pig, tail biting
It is widely accepted that the most valid approach to animal
welfare assessment is to focus on the animal rather than its
environment (Keeling & Veissier 2005; Smulders et al 2006;
Main et al 2007). Consequently, assurance schemes increas-
ingly measure ‘welfare outcomes’ such as the prevalence of
skin lesions in pigs (Sus scrofa domesticus) (Velarde &
Geers 2007). Abattoir meat inspection involves examination
of each carcase and, hence, presents an ideal opportunity to
measure animal-based welfare outcomes (Harley et al
2012a). The extensive use of meat inspection data in
epidemiological studies over a number of decades corrobo-
rates this (Cleveland-Nielsen et al 2004; Mullan et al 2011;
Swaby & Gregory 2012). Additionally, meat inspection is a
cost effective means of collecting data over long time-
periods as it is a continuous practice which is already in
place (Huey 1996; Cleveland-Nielsen et al 2004). For this
reason, and also for biosecurity reasons, it has advantages
over welfare inspections of pigs at farm level.
Tail biting is a major welfare problem in modern pig
farming systems. In spite of a ban on routine tail docking,
many pigs are still tail docked in EU countries (eg Harley
et al 2012b) in an attempt to control tail biting. There have
been extensive investigations into the epidemiology and
consequences of tail biting (Wallgren & Lindahl 1996;
Moinard et al 2003; Sinisalo et al 2012). Its reported asso-
ciation with carcase disease lesions, decreased carcase
weights and condemnations at slaughter means that it has
adverse economic implications for producers (Huey 1996;
Valros et al 2004; Kritas & Morrison 2007; Heinonen et al
2010). Furthermore, tail wounds are an important welfare
outcome measure (EFSA Panel on Animal Health and
Welfare 2007) as lesions seen at slaughter can generally be
attributed to practices at farm level. Indeed, a recent
technical report to EFSA on the future development of
animal-based measures for assessing the welfare of pigs
recommended that tail length and injury status be monitored
in slaughter pigs (Spoolder et al 2011).
Universities Federation for Animal Welfare Science in the Service of Animal Welfare
276 Harley et al
During an earlier study of over 36,000 slaughter pigs by
Harley et al (2012b), several other lesions potentially related
to pig welfare were readily observed. These included loin
bruising and hind limb bursitis. Anecdotal evidence from
pigmeat processors in the Republic of Ireland (where entire
male pigs are produced) suggests that the prevalence of loin
bruising is increasing. This lesion necessitates carcase
trimming at the processing stage and therefore results in
downgrading of the value of the loins. This contributes to
financial losses for the processor which have not been quan-
tified. Both the localisation of the bruising to the loin region
and its diffuse nature suggests that mounting behaviour plays
a part in its aetiology. Mounting is performed as part of the
sexual behavioural repertoire of entire male pigs (Conte et al
2010). When a male pig mounts another, its sternum applies
significant pressure to the loin area of the pig being mounted
(L Boyle, personal observation 2012). This may cause injury,
and usually elicits vocalisations and escape behaviour by the
mounted pig, which are suggestive of poor welfare
(Faucitano 2001; Rydhmer et al 2006).
Bursitis is a lesion found on the metatarsal region of the hind
limbs of pigs (Gillman et al 2008). Bursae are naturally
occurring fluid-filled sacs that decrease friction at points
where muscles and tendons glide over bones (McFarland et al
2000). Bursitis is a pathological response to trauma, the preva-
lence and severity of which is influenced by the degree of
pressure exerted on the limbs by commercial pig flooring
systems (Smith 1993; Lyons et al 1995; Mouttotou et al
1998). It is therefore representative of sub-optimal environ-
mental conditions on farms (Gillman et al 2008; Kilbride et al
2008). Bursitis has implications for animal welfare, not least
due to its associations with lameness, which can infringe all of
the five freedoms (Heinonen et al 2013).
Harley et al (2012b) conducted investigations in Irish and
Northern Irish abattoirs and provided herd-level data on the
prevalence of tail biting and of carcase condemnation.
Studies in Northern Ireland and other parts of Europe
(Tuovinen et al 1994; Huey 1996; Hunter et al 1999; Valros
et al 2004; Martínez et al 2007) also explored tail biting in
this way. However, the potential link between tail lesion
severity and carcase weight does not appear to have been
investigated previously. Similarly, the prevalence of other
welfare outcomes in slaughter pigs (such as loin bruising
and bursitis), and their effects on economically important
parameters, such as carcase condemnations and carcase
weight, have not been investigated. Consequently, the aims
of this study were: i) to determine the prevalence of loin
bruising and severe hind-limb bursitis; ii) to assess pig-level
associations between these welfare-related lesions (and tail
lesions) and carcase condemnation, carcase trimming and
carcase weights; and iii) to estimate the financial losses
associated with the parameters measured. It was postulated
that such information might strengthen the case for devel-
oping meat inspection as an animal welfare surveillance
tool in the Republic of Ireland which could, in turn,
contribute not only to improvements in pig productivity,
health and welfare, but also to the profitability of pig
production at producer and processor level.
Materials and methods
Data collection
Data collection was carried out by four people over seven
days during April 2012. The study took place in a single
abattoir with a weekly throughput of approximately
10,500 pigs (circa 20% of total pigs slaughtered per week in
the Republic of Ireland during April 2012) (Irish Central
Statistics Office 2012). Data collection began at 0900h and
continued until the end of the working day at approximately
1800h. The appropriate sample size for the study was
generated using data from the literature (Valros et al 2004)
and AusVet Epitools software (AusVet Animal Health
Services 2009). To account for the effect of clustering at
herd level, the sample size was expanded by 15% (Dohoo
et al 2003), to 3,492 study pigs. The sampling interval of
every third pig on the slaughterline was determined by
dividing the study population size (in this case weekly
abattoir throughput) by the required sample size (Dohoo
et al 2003; EFSA 2011).
Data were collected at three points on the slaughter line: i)
between dehairing and evisceration; ii) at post mortem meat
inspection; and iii) at the weighing scales. An identification
tag was suspended from one hind foot of each study pig at
the first data collection point, enabling identification of
study pigs at the later stages. Pig gender and herd identifica-
tion code were also recorded at this stage. The latter measure
enabled estimation of batch size, which is correlated with
herd size (Harley et al 2012b). Tail and loin lesion scoring
also occurred at the first data collection point and was
conducted by the same person throughout. Tails were scored
on a 0–4 scale (Figure 1). As it was already established that
over 99% of Irish pigs are tail docked (Harley et al 2012b),
tail length was not recorded in this study. Loin bruising was
recorded on a three-point scale (Figure 2).
The reason and anatomical locations of carcase condemnations
and trimmings were recorded by the second data collector at
the point of meat inspection, on the basis of the decision of the
acting Department of Agriculture, Food and the Marine
(DAFM) Temporary Veterinary Inspector(s) (TVI) on the line
(see Table 1). Hind-limb bursitis (see Figure 3) was recorded as
severe or absent/mild by the same person at this point. Partial
condemnations (ie, removal of a limb/head on public health
grounds and trimmings (ie, removal of a superficial
lesion — tail abscess, bursitis, skin wound) from the study pigs
were weighed by a third person. It was not possible to weigh
carcases that were entirely condemned.
There were three TVI teams, each of three people, working
separate shifts to the following schedule each day: shift 1,
0700–1030h; shift 2, 1050–1420h; and shift 3, 1450–1750h.
For the majority of shifts, the TVI teams included the same indi-
viduals, however there were some substitutions during the study.
At the third data collection point, a fourth person
recorded the line ‘kill number’ of each study carcase and
removed the identification tag from the leg of study
carcases before they entered the chill rooms. Using this
© 2014 Universities Federation for Animal Welfare
Welfare lesions in slaughter pigs 277
approach, it was possible to subsequently capture the
carcase weight and grade of each study pig. The carcase
weight of a pig correspond ed to th e cold weight
following bleeding and removal of the internal organs
(including genitalia), tongue, bristles, hooves and flare
fat (Irish Central Statistics Office 2012).
Data analysis
Descriptive statistics were calculated using Microsoft®
Excel® for Windows. Tail-biting scores were re-organised
into four categories: no lesion (score = 0); any tail lesion
(score 1); moderate lesions (score 2); and severe lesions
(score 3). Carcase condemnations, trimmings and absces-
Animal Welfare 2014, 23: 275-285
doi: 10.7120/09627286.23.3.275
Figure 1
Tail-lesion scoring system (Scores 0–4, left to right).
Figure 2
Loin-bruising scoring system (Scores 0–2, left to right).
Figure 3
Hind-limb bursitis (absent/mild and severe, left to right).
278 Harley et al
sation were classified as present (score = 1) or absent
(score = 0). Loin bruising was recorded on a three-point
scale which was collapsed to either severe (score of 2) or
none/mild (scores of 0+1).
The relationship between gender of the pigs and welfare
lesions (tail lesions, loin bruising and hind-limb bursitis)
were analysed using generalised estimated equations in
PROC GENMOD of SAS (SAS Institute Inc 1988).
Gender was considered as the dependent variable.
Univariable models were built separately to assess the
influence of each predictor variable on the dependent
variables. Tail lesions, loin bruising and hind-limb bursitis
were included as categorical variables.
The relationship between welfare indicators (tail lesions,
loin bruising and hind-limb bursitis) and the total number of
carcase condemnations (partial + entire), carcases
condemned for abscessation and carcases trimmed were also
analysed using generalised estimated equations in PROC
GENMOD of SAS (SAS Institute Inc 1988). Total carcase
condemnations, carcases condemned for abscessation and
carcases trimmed were considered as the dependent
variables. Firstly, univariable models were built to separately
assess the influence of each predictor variable on the
dependent variables. Predictor variables with P< 0.20
(Dohoo et al 2003) were used to build multivariate models.
TVI shift and gender were forced into the models to assess
their influence on the outcome variables. The tail-lesion
scores were also included as a categorical variable in the
model for carcases condemned for abscessation. Tail-lesion
scores and hind-limb bursitis scores were included in the
model for total number of carcase condemnations. Finally,
tail-lesion and loin-bruising scores were included as categor-
ical variables in the model for carcases trimmed. Backward
selection was used to eliminate predictor variables until only
those with P< 0.05 remained in the model.
Carcase weight was tested for normality before analysis
using the Shapiro-Wilk test and examination of the normal
plot. One hundred and ninety-four carcases were excluded
from the analysis of the relationship between the severity of
welfare lesions and carcase weight as their weight was
reduced because of being partially/entirely condemned
and/or trimmed. The relationship between welfare lesions
and carcase weight was assessed using mixed model
equations in PROC MIXED (SAS Inst Inc, Cary, NC, USA).
Tail-lesion score, loin bruising and hind-limb bursitis were
included as fixed effects and carcase weight as a random
effect. Statistical differences were reported when P< 0.05.
Results are reported as least square means (± SEM).
The direct financial losses resulting from carcase condemna-
tion and trimming at the point of meat inspection were calcu-
lated by multiplying recorded weights of condemned and
trimmed material by the average Irish pig meat price at the
time of writing up the study (1.70 per kg) (Cleary 2012),
using Microsoft® Excel® for Windows v 2000. In the
absence of weights of carcases that were entirely condemned,
the average weight for such carcases based on recordings
made at Northern Irish abattoirs as per Harley et al (2012b)
was used. It was not possible to weigh or calculate the losses
associated with fat/muscle trimming beyond the point of meat
inspection and thus the impact of loin bruising on trimming
during processing could not be evaluated.
In the economic analysis, the potential impact of tail-lesion
severity on final carcase weight considered the carcase
weight for each score 2 relative to carcases with tail-lesion
scores of 0 or 1 (ie, unaffected carcases). Carcases that were
partially condemned or trimmed were not included in this
analysis as they would automatically have been lighter irre-
spective of their tail-lesion score.
Descriptive results
A total of 3,537 pigs were observed during the study. In the
absence of a full dataset for 115 of the pigs, the final study
population was 3,422 pigs. A general description of the
study population is shown in Table 2. Of the final study
population, 85 carcases were condemned. The majority
were partial condemnations, of which the hindquarters were
the most commonly affected anatomical region.
Abscessation alone accounted for almost 70% of total
condemnations. Carcase trimming occurred more
frequently than condemnation; cumulatively 5.7% of the
study population was either trimmed or condemned.
Tail lesions (score 1) were observed in 72.5% of the study
pigs (Table 2), with 2.5% affected by severe tail lesions (ie,
© 2014 Universities Federation for Animal Welfare
Table 1 Definition of disease lesions and carcase condemnations* as per Straw et al (2006) and Ellerbroek et al (2011)
detected at meat inspection.
Anatomy affected Disease Appearance/description
Entire carcase* Various Systemic disease
Partial carcase* Localised disease/injury
Hindquarter* Localised disease/injury affecting one or both hind limbs
Forequarter* Localised disease/injury affecting one or both forelimbs
Abscess Abscessation Single or multiple focal, spherical, encapsulated purulent lesions
Other infectious Septicaemia, septic peritonitis/endocarditis/arthritis Localised or systemic caused by an infectious agent
Trimmings Various Small, superficial disease/injury lesion/external abscess
Welfare lesions in slaughter pigs 279
Animal Welfare 2014, 23: 275-285
doi: 10.7120/09627286.23.3.275
Table 2 General description of the study population, including the prevalence of carcase condemnations and trimmings,
tail and loin lesions, hind-limb bursitis and carcases condemned for abscessation.
Four carcases were both trimmed and condemned.
Total % study population
Farms 49 –
Batches 74 –
Pigs Male 1,777 51.9
Female 1,645 48.1
Total 3,422 100.0
Condemnations Total 85 2.5
Entire carcase 14 0.4
Partial carcase 71 2.1
Partial condemnations Hindquarters 48 1.4
Forequarters 10 0.3
Head 8 0.2
Other 5 0.1
Causes Abscessation 58 1.7
Other 27 0.8
Trimmings 113 3.3
Trimmings and condemnations194 5.7
Welfare lesions
Tail lesions None Male 401 22.6
Female 540 32.9
Total 941 27.5
Score 1 Male 1,376 40.2
Female 1,105 32.3
Total 2,481 72.5
Score 2 Male 533 15.6
Female 371 10.8
Total 904 26.4
Score 3 Male 67 1.9
Female 20 0.6
Total 87 2.5
Loin bruising None/mild Male 1,493 43.6
Female 1,380 40.4
Total 2,873 84.0
Severe Male 284 8.3
Female 265 7.7
Total 549 16.0
Hind-limb bursitis None/mild Male 984 28.7
Female 934 27.3
Total 1,918 56.0
Severe Male 793 23.2
Female 711 20.8
Total 1,504 44.0
Carcase condemned for abscessation
Tail lesions None 23 0.7
Score 1 62 1.8
Score 2 33 1.0
Score 3 13 0.4
280 Harley et al
score 3). Males were more frequently affected by tail
lesions than females, a trend which became exaggerated
with increasing tail-lesion severity (Score 1: OR = 1.55;
95% CI 1.314–1.819; P < 0.001; Score 2: OR = 1.78; 95%
CI 1.479–2.160; P < 0.001; Score 3: OR = 4.51; 95% CI
2.693–7.556; P< 0.001). Severe loin bruising affected
16.0% of pigs and severe hind-limb bursitis was detected in
almost half the study population. Male gender was not a risk
factor for severe loin bruising (OR = 0.99; 95%
CI 0.825–0.189; P> 0.05) or severe hind-limb bursitis
(OR = 1.06; 95% CI 0.924–1.212; P> 0.05).
Factors affecting carcase condemnations and trimmings
Hind-limb bursitis, tail-lesion score and gender were signif-
icantly associated with carcase condemnation (P 0.05;
Table 3). Tail lesions with a score 3 and male gender
increased the risk of condemnations, whilst bursitis was a
protective factor. TVI shift and loin bruising were not
significantly associated with carcase condemnations. Tail
lesions with a score 3 and TVI were significantly
associated with carcase trimming (P 0.05).
Factors affecting carcase weight
There was a significant negative effect of tail-lesion
severity score on carcase weight (P 0.05) such that there
was an average reduction in weight of 1.19, 3.27 and
12.0 kg associated with tail lesions scored 2, 3 and 4,
respectively, relative to tails scored 0 or 1 (Table 4). In
contrast, there was no effect of loin bruising or hind-limb
bursitis on carcase weights (P> 0.05).
Economic analysis
The pigmeat losses associated with the 85 carcase condemna-
tions in the study population amounted to over 1,800 kg and had
a value of more than 3,200. This equated to 0.94 per study pig
and increased to 1.10 per study pig when costs associated with
approximately 330 kg of trimmings were included (Table 5).
© 2014 Universities Federation for Animal Welfare
Table 3 Final generalised estimating equation (GEE) model of risk factors associated with carcase condemnation
(includes entire and partial condemnations), carcases condemned for abscessation and carcases trimmed. The variables
gender and Temporary Veterinary Inspector (TVI) shift were forced into the final model.
* Significantly different from reference category; P 0.05.
OR = Odds ratios.
CI = 95% confidence interval.
NI = Not included in the model.
Explanatory variables Carcase condemnation Carcase condemned for abscessation Carcase trimmed
Tail lesion score 0
1 0.66 0.380–1.159 1.22 0.347–4.308 0.86 0.503–1.456
2 0.85 0.461–1.572 1.74 0.417–7.262 1.26 0.702–2.246
3 5.07* 2.428–10.581 0.78 0.167–3.656 25.84* 13.83–48.29
Gender Female (0)
Male (1) 2.55* 1.547–4.200 0.26 0.067–1.003 0.70 0.463–1.059
TVI shift 1
2 0.97 0.546–1.704 0.27 0.064–1.136 1.09 0.665–1.794
3 0.89 0.480–1.650 0.44 0.092–2.144 0.52* 0.286–0.961
Hind-limb bursitis None/mild
Severe 0.59* 0.373–0.950 NI NI NI NI
Loin bruising None/mild
Severe NI NI NI NI 0.67 0.438–1.023
Table 4 Mean SEM) carcase weight (kg) of pigs (not
condemned and/or trimmed) in each of the tail lesion,
loin lesion and hind-limb bursitis score categories.
abc Carcase weights differ significantly (P 0.05).
Welfare-related lesions Carcase weight
Tail lesion score
1 80.02 (± 0.18)a
2 78.83 (± 0.31)b
3 76.75 (± 1.45)b
4 68.02 (± 2.28)c
Loin bruising
None/mild 79.63 (± 0.17)
Severe 79.53 (± 0.36)
Hind-limb bursitis
None/mild 79.46 (± 0.20)
Severe 79.79 (± 0.23)
Welfare lesions in slaughter pigs 281
The total estimated reduction in carcase weight in the study
population when tail lesions were scored greater than 1 was
1.182 kg (Table 5). This equated to a loss of 0.59 per pig
in the final study population. There was an estimated loss of
1.69 per study pig when the value of pigmeat lost as a
result of carcase condemnation/trimming and reduced
carcase weights were combined.
Data recording at abattoir meat inspection is a valuable
way of monitoring the prevalence of a number of health
and welfare conditions that affect food-producing animals.
This study found a high prevalence of tail biting, loin
bruising and hind-limb bursitis, as well as a high frequency
of carcase condemnations within the study population. In
association with these findings, considerable financial
losses were identified which were primarily associated
with lesions caused by tail biting. These findings highlight
the potential value of enhanced data capture and feedback
at abattoir meat inspection.
In this study, 72.5% of inspected pigs had detectable tail
lesions. This figure is higher than the mean prevalence of
detectable tail lesions found by Harley et al (2012b) for
over 36,000 pigs. However, the abattoir involved in the
current study was also included in the study by Harley et al
(2012b), and the current figure corresponds well with the
previous figure for detectable tail lesions in slaughter pigs
of 76% in that abattoir under the same scoring system.
Harley et al (2012b) discussed some of the potential
reasons why the prevalence of detectable tail lesions in the
pigs supplied to this particular abattoir was so high
compared to the national average. However, even the
national average figure for pigs affected by detectable tail
lesions demonstrates that tail biting is a widespread behav-
ioural problem, and that the widely practised control
method of docking (Harley et al 2012a) is ineffective.
The observed prevalence of tail lesions in this study is much
higher than reported for other countries where comparable
studies were conducted (Finland: Valros et al [2004] and
Sweden: Keeling et al [2012]). This may reflect differences
in animal welfare policy (eg, tail docking is totally banned
in Finland) and farm management. For example, straw is
widely used in pig production in Sweden and this is likely
to have had a significant positive impact on tail biting
(EFSA Panel on Animal Health and Welfare 2007).
Nevertheless, the lesion-scoring systems and lesion
threshold criteria used also differed greatly between the
studies, and this will have influenced the findings on tail
lesions (Keeling et al 2012). Furthermore, the location
where the tails were inspected differed between the three
studies. In both the current study and the study by Valros
et al (2004), pigs were inspected after scalding whereas they
were inspected after exsanguination in the study by Keeling
et al (2012). Based on our observations, minor lesions
(scores 1 and 2 in this study) are not detectable unless the
pigs are scalded and dehaired. Keeling et al (2012) cite
concerns about mechanical damage to the tails during the
scalding process as a reason for choosing their scoring
location. However, the fact that gender differences
prevailed even between the milder scores in the study by
Animal Welfare 2014, 23: 275-285
doi: 10.7120/09627286.23.3.275
Table 5 Weight (kg) of carcase condemnations and trimmings, the average reduction in carcase weight associated
with tail-lesion score and their associated financial cost ().
Using the average weight of entirely condemned carcases recorded by Harley et al (2012b).
Using average Irish value for pig meat over the study period (1.70 per kg).
§Four carcases were both trimmed and condemned.
Prevalence (number of pigs affected) Weight (kg) Cost ()(Total) Cost ()(Per study pig)
Carcase condemnations
Entire 14 977.621,661.95 0.48
Partial 71 911.53 1,549.60 0.45
Total 85 1,889.15 3,211.55 0.94
Carcase trimmings
Total 113 329.84 560.73 0.16
Cumulative carcase condemnations and trimmings§
Total 194 2,218.99 3,772.28 1.10
Potential loss associated with final carcase weight
Score 2 (less 1.19 kg) 774 921.06 1,565.80 0.46
Score 3 (less 3.27 kg) 32 104.64 177.89 0.05
Score 4 (less 12 kg) 13 156.00 265.20 0.08
Total 1,181.70 2,008.89 0.59
Cumulative carcase condemnations, trimmings and loss in carcase weight
Total 3,400.69 5,781.17 1.69
282 Harley et al
Harley et al (2012b) suggests that the aetiology of such
damage is animal-based and not mechanical.
Tail-biting lesions provide not only a point of entry for
infection (Heinonen et al 2010), but three separate routes for its
dissemination around the body (venous, lymphatic and
cerebro-spinal drainage) (Huey 1996). Hence, there is a close
association between tail lesions and abscessation (Huey 1996;
Valros et al 2004; Heinonen et al 2010). However, in spite of
the high prevalence of tail damage in the current study, no
significant association between tail lesions and condemnation
due to abscessation was detected. This may possibly reflect the
smaller sample size and subsequent inadequate statistical
power of the current study relative to those mentioned above.
However, there was a significant association between the
severity of tail lesions and carcase condemnations, and
abscesses were the primary cause of condemnations.
The findings of the current study support observations by
Harley et al (2012b) that, similar to castrates (Hunter et al
1999; Valros et al 2004), entire male pigs are more
frequently and severely affected by lesions caused by tail
biting than females. The reason behind gender differences in
propensity to be (severely) bitten has yet to be established
(Schrøder-Petersen & Simonsen 2001; Taylor et al 2010).
However, our findings extend those of Harley et al (2012b)
by showing that male carcases are also more likely to be
condemned than female carcases. Even though there was no
association between gender and condemnation for abscessa-
tion, it is probable that the greater likelihood of males having
internal infections arising from tail lesions was responsible
for the increased risk of condemnation. These findings need
to be confirmed with larger numbers of animals.
We can conclude from the above that tail biting is a major
cause of financial loss to producers arising from carcase
condemnation. However, severe tail lesions are also positively
associated with carcase trimming which represents another
source of financial loss not only to the producer because of the
reduction in carcase weight but also to the processor because
of the associated labour. The direct losses to producers from
carcase condemnations and trimmings recorded in this study
were valued at 1.10 per pig slaughtered.
Another source of financial loss associated with tail biting
arises from the reduction in animal performance (Sinisalo
et al 2012) which, in this study, was reflected in the lower
weights of carcases affected by tail lesions. It is likely that
inflammatory processes associated with infection arising
from the tail lesions (Valros et al 2004) interfered with
growth performance, but the effect of stress on the victim of
tail biting cannot be discounted (Schrøder-Petersen &
Simonsen 2001). It could be argued that lighter/smaller pigs
are more susceptible to being bitten, however, there is little
scientific evidence to support this. In fact there is evidence
that smaller pigs (or ‘runts’) are more likely to be tail biters
(Van de Weerd et al 2005).
The most severe tail lesions were associated with carcases
which were, on average, 12 kg lighter than unaffected
carcases (ie, carcases with a tail score of 0 or 1). However,
even carcases with tail-lesion scores of two (which could be
considered to be relatively ‘mild’ lesions) were associated
with a 1.2 kg reduction in weight relative to unaffected
carcases. Such lesions likely arise from tail
manipulation/chewing (rather than biting) which can occur
at chronically high levels in intensive pig production systems
(Schrøder-Petersen & Simonsen 2001). It is possible that this
can occur even in the absence of severe/acute outbreaks of
tail biting, ie those leading to cannibalism. Producers are
often unaware that tail manipulation is being performed
because of the absence of blood and of overt behavioural
reactions of the recipient. In spite of this, tail manipulation is
likely a stressor, with implications for animal performance
and therefore for profitability at farm level. Information on
these minor/moderate tail lesions might lead producers to
improve the types/quantities of environmental enrichment
provided to pigs as this could reduce levels of tail manipula-
tion (Taylor et al 2010) or to make other management
changes, eg reduce stocking densities, improve ventilation
etc. Such changes would not only lead to improvements in
pig welfare but could also improve farm finances. Minor,
and sometimes moderate, lesions are not visible on the live
animal. Therefore, the only way in which producers can be
provided with information on such lesions, to inform their
herd health and welfare management plans, is if they are
recorded on the carcase at meat inspection.
As producers are paid on a per kg basis, a reduction in
carcase weight represents a serious financial loss to
producers. The lost potential carcase weight associated with
tail lesions was equivalent to 1,181.70 kg or 0.59 per pig
slaughtered. When combined with losses arising from
carcase condemnation (1.10 per pig), the resulting figure
of 1.69 represents almost 43% of the current profit margin
(estimated at 0.05 kg or circa 3.95 per 79 kg carcase) for
Irish pig producers. In the context of increased production
costs in a number of EU countries since 2010 (BPEX 2012),
such losses represent a serious threat to the viability of pig
farms. In an industry with such tight margins, financial
implications such as these may act as a significant driver for
addressing the problem of tail biting by improving pig
husbandry and welfare.
This study is the first to report on the prevalence of loin
bruising as a welfare outcome at slaughter. Severe bruising
was detected in 16.0% of study carcases, confirming
anecdotal reports from processors in the Republic of Ireland
that loin bruising is prevalent in slaughter pigs. It was
beyond the scope of this study to determine the aetiology of
loin bruises but the absence of a gender effect on this lesion
could reflect the fact that most pigs are kept in mixed sex
groups on Irish farms and entire male pigs in mixed sex
groups mount other males as frequently as they mount
females (Conte et al 2010). Severe loin bruising also incurs
costs to processors (L Boyle, personal communications with
pigmeat processors 2012). This is because affected cuts are
downgraded, diminishing the retail value by over 50%, and
the removal/trimming of damaged tissue incurs labour and
disposal costs. Such trimming occurs at the processing stage
and was not included in the trimming measured in this study
© 2014 Universities Federation for Animal Welfare
Welfare lesions in slaughter pigs 283
(which took place on the slaughter line). Hence, the specific
financial impact of such welfare lesions is unknown.
Trimming of bruised loins often removes the rind upon
which slapmarks or kill numbers are stamped, preventing
identification of producers with batches showing a high
prevalence of loin bruising. However, scoring of loin
bruising at meat inspection provides a solution to this
problem because the identification of the producer can be
recorded simultaneously. If the financial impact of loin
bruising is established, processors may consider introducing
penalties for carcases with bruised loins in the future. Hence,
a better understanding of the aetiology of such lesions will
be required in order to be able to advise pig producers on
ways to reduce these lesions in their slaughter pigs.
Though it is difficult to quantify its implications for produc-
tivity and profit, hind-limb bursitis is a valuable indicator of
flooring quality (Gillman et al 2008). Hind-limb bursitis
was identified in 44% of pigs in this study, in contrast to a
lower prevalence observed in finishing pigs in the UK
(Kilbride et al 2009). This may reflect the fact that straw-
based systems are more commonly employed in the UK
than in the Republic of Ireland. The current study provides
further evidence that concrete slatted flooring (which is the
predominant flooring used in intensive systems of pig
production in the Republic of Ireland) has adverse effects on
limb health. There is a strong relationship between bursitis
and lameness (Kilbride et al 2009), but it is not known
whether bursitis causes lameness or is simply a conse-
quence of lameness, mediated perhaps by prolonged lying
in lame animals (Bonde et al 2004). However, the relation-
ship between bursitis and lameness suggests that it is a good
measure of on-farm welfare, and this is supported by the
fact that it is included in the Welfare Quality® protocol
(Welfare Qualit 2009). Lameness in pigs is associated
with large industry losses arising from decreased produc-
tivity and rejection of breeding animals (Kilbride et al
2009), so bursitis potentially merits inclusion for measure-
ment at meat inspection as an animal welfare surveillance
measure. The finding that hind-limb bursitis was a protec-
tive factor for the risk of condemnation was unexpected and
is difficult to explain.
It is worth noting that abattoir meat inspection has limita-
tions as a tool for animal welfare surveillance. Severely
affected animals may die or be culled during production,
whilst detection and recording of lesions that resolve pre-
slaughter is similarly impossible. Consequently, the preva-
lence of welfare lesions recorded at meat inspection is likely
to underestimate that on-farm (Marques et al 2012).
Conversely, lesions occurring during transport or lairage, eg
limb fractures and fresh tail lesions, may cause an overesti-
mation of the prevalence at production level.
Despite the above limitations and as illustrated in this
study, the health and welfare status of food-producing
animals can be assessed and recorded during abattoir meat
inspection (Alban et al 2011; Swaby & Gregory 2012).
Denmark and The Netherlands are examples of countries
which routinely record such information and use it to
target problem areas at production level (Willeberg et al
1984; Stärk 1996; Nielsen 2011). Indeed, producers
provided with such information have lower incidences of
disease and welfare problems on their farms (Sanchez-
Vazquez et al 2011). However, despite the potential value
of this information, many countries still have no recording
and feedback system in place (Harley et al 2012b).
Animal welfare implications
This paper outlines the high prevalence of three welfare
lesions detected at slaughter, and their association with
carcase condemnations, trimmings and carcase weight.
Additionally, it calculates the financial losses incurred by
pig producers as a result of carcase condemnations,
trimmings and reduced carcase weights primarily associated
with lesions caused by tail biting. Importantly, the paper
also illustrates that the behaviour of tail manipulation, as
opposed to tail biting, is highly prevalent on farms, and, for
the first time, that the resulting minor to moderate lesions
are also associated with significant reductions in carcase
weight. This paper also illustrates that there are significant
advantages associated with monitoring the incidence and
severity of a number of animal diseases and welfare
outcomes during the process of abattoir meat inspection.
Expansion of the meat inspection process to incorporate
such lesions has the potential to be highly valuable for
producers and the pig industry as a whole.
The authors acknowledge the financial support provided by
the Wellcome Trust Intercalation Funding Award for Sarah
Harley and the Irish Government’s National Development
Plan 2007–2013 for Dayane Teixeira (Department of
Agriculture, Food and the Marine’s Competitive Research
Programme – RSF 11/S/107). We thank the abattoir manager
and staff for their co-operation and Dr Paul Whyte and Tracy
Clegg of UCD for their advice. Great thanks to staff of the
Teagasc Pig Development Department (PDD) (Tómas Ryan
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... The findings from the present study indicate the capacity of ante- There is a high likelihood that carcasses from pigs affected by tail lesions will be fully condemned and the affected carcasses are lighter (Harley et al., 2014). Hence, it could be argued to what extent tail lesion severity could justify euthanasia of affected pigs on farm, avoiding financial losses associated with reduced feed efficiency and treatment, unnecessary animal suffering and the potential misuse of antibiotics (Boyle et al., 2022). ...
... As expected, batches with carcasses affected by tail lesions were associated with entire and partial carcass condemnations, corroborating findings from previous studies in Finland and Ireland (Harley et al., 2014;Valros et al., 2004). In fact, 50% of batches with pigs affected by tail lesions alone had carcasses entirely condemned. ...
... The major financial loss was associated with carcass weight as batches with pigs affected by more than one welfare issue were nearly 10 kg lighter than those without welfare issues. Also, the potential financial implication associated with carcass condemnations was especially triggered by tail lesions, which corroborates findings from (Harley et al., 2014). All these confirm the assumption that animal welfare condition on farm is associated with productive performance. ...
This study aimed to investigate the associations between severe ear, tail, and skin lesions, hernias, bursitis, and rectal prolapses and meat inspection finding in slaughter pigs, including carcass weight and financial implications associated with carcass condemnations at batch level. Data were collected from 13,296 pigs from 116 batches from a single abattoir. Spearman's correlation coefficients were calculated to analyze the degree of association between the prevalence of welfare issues and condemnation findings. The association between batch-level results of carcass weight, batch size, and the prevalence of welfare issues was analyzed using generalized linear mixed models. The prevalence of tail lesions was significantly associated with both entire (r = 0.224; p = 0.0432) and partial (r = 0.276; p = 0.0120) carcass condemnation. Batches with pigs affected by more than one welfare issue were 9.9 kg lighter than those without welfare issues (p < 0.05), which was equivalent to a potential loss of €11.28 per pig. Our findings indicate that ante-mortem inspection could be useful to predict post-mortem findings at batch level and that welfare issues in pigs represent a financial loss to producers, as they are paid on a per kg basis and have tight margins.
... Abattoir inspections provide a valuable tool for animal health and welfare monitoring, a source of data for epidemiological surveillance, and an opportunity for disease and lesions investigation that is more cost-effective for many pathologies and conditions than collecting data on farm [5,6]. Regarding tail lesions at slaughter, some studies have shown that such lesions, however mild, increased pleuritic and lung lesions, and that the risk increases with the severity of tail lesions [7]. However, other studies failed to find any correspondence [8][9][10]. ...
... Tail biting and respiratory disease have also been described as the cause of similar effects on performances, such as lower carcass weight and higher carcass condemnation and/or carcass trimming [6,12]. In fact, other authors have reported a correlation between tail biting outbreaks and poor health conditions [7,13], leaving open the discussion about the relationship between respiratory disease and tail lesions. However, in the knowledge of the authors, literature is poor of investigations on the potential connection of these parameters between entire batches of pigs with undocked tails versus docked ones, as the majority of the studies mentioned above were performed on mainly docked animals. ...
... Actually, the percentage of docked animals with tail lesions was close to zero, opposite to the frequency of 44.0% of pigs with undocked tail showing damage. Results regarding the proportion of lesions in docked animals were in agreement with the low prevalence in heavy pigs reported by other authors [15,31,32], even if studies on lighter pigs in Europe showed higher frequencies and strong differences among countries, with values ranging from a prevalence of 72.5% [7] to 20-30% [33,34]. These differences were mainly explained by the large variability reported among different farms and batches [34], probably due to the unpredictable and multifactorial origin of tail biting [35]. ...
Full-text available
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 < 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.
... It is important to note that any comparison with the prevalence of welfare lesions from the present study is not pertinent as batches with animals from hospital pens were purposely evaluated and included in this study to increase the probability of collecting data from more animals with the selected welfare outcomes and its association with post-mortem outcomes. However, the association between the prevalence reported by and the carcass condemnations in the current study shows the magnitude of the tail T A B L E 3 General description of the study population for the second phase of the study, including the percentage of carcass affected by each welfare outcome T A B L E 4 Least square mean (± SEM) weight (kg), pH, and temperature of carcass with none or one animal-based welfare outcome and not condemned and/or trimmed biting behavior problem on farm, corroborating findings from previous studies in Finland and Ireland (Harley et al., 2014;Valros et al., 2004). ...
... However, similar to Harley et al. (2014), our findings do not show an association between tail lesions and lung condemnations or carcass abscessation. This was unexpected as the majority of papers shows such an association between tail lesions and these post-mortem outcomes (Heinonen et al., 2010;Huey, 1996;Teixeira et al., 2016;Valros et al., 2004;van Staaveren et al., 2016) a potential mechanism for which was outlined by Boyle et al. (2022). ...
... Carcasses from pigs affected by tail lesions showed a reduction in weight of 3.6 kg, corroborating previous studies (Harley et al., 2014;Valros et al., 2013;Vom Brocke et al., 2019). In fact, Harley et al. (2014) reported a reduction in carcass weight of 1.2, 3.27, and 12 kg in cases of mild, moderate, and severe tail lesions, respectively. ...
Full-text available
The aim of this study was to investigate associations between ear, tail, and skin lesions, hernias, bursitis, and rectal prolapses at the abattoir and meat inspection outcomes in slaughter pigs, including carcass condemnations and trimmings, carcass weight, and carcass quality. This was an observational study whereby pigs were managed according to routine practices in a single abattoir. Data were collected from 1816 pigs. The relationship between animal‐based welfare and post‐mortem outcomes was analyzed using generalized mixed models (Proc Glimmix). Our findings showed that tail lesions were associated with entire carcass condemnations and trimmings (P < 0.001), a reduction in carcass weight (P < 0.05), and a potential to impair carcass quality by reducing muscle pH (P < 0.05), especially in carcasses from male pigs (P < 0.05). Additionally, hernias were associated with viscera condemnation (P < 0.05) and a reduction in carcass weight (P < 0.05). Therefore, our findings confirm that ante‐mortem inspection could be useful to predict post‐mortem outcomes in the same pigs, especially in cases of tail lesions and hernia, which might trigger attention of the veterinary inspector in charge of the post‐mortem inspection.
... Tail biting poses a significant risk to the welfare of pigs in modern intensive farming, resulting in serious economic losses [1] while threatening the economic sustainability of the pig farming sector [2]. This abnormal behavior can cause acute pain in bitten pigs [3]. ...
Full-text available
Simple Summary Tail biting is an abnormal behavior of pigs, posing serious welfare and economic challenges in intensive pig farming. There are no studies on the perceptions of farmers in south European countries on tail biting and tail docking. This study aims to examine the attitudes of Greek pig farmers toward tail biting and tail docking through a structured questionnaire. In case of an outbreak, the Greek farmers mainly choose to remove the victim, while 64.4% have tried at least once to raise pigs with intact tails. Chains are still the most commonly used enrichment material. Feed quality, environmental factors, and health problems are considered the most important risk factors. The study indicates that solutions for effectively reducing the need for tail docking should consider farmers’ perceptions and everyday practices. Abstract Tail biting is both an important economic and a welfare problem. The primary preventive measure, almost on a routine basis throughout Europe, remains tail docking following a risk analysis. This study aimed to get insight on the perceptions of Greek pig farmers towards tail docking, intervention measures, and risk factors of tail biting, as well as opinions on pig welfare themes. Eighty-two farmers answered a questionnaire provided online and in printed form. In the case of a tail-biting outbreak, the most important intervention measure is the removal of the bitten pig (victim), while feed quality, air movements, and stocking density were ranked as the highest risk factors (p ≤ 0.05). Chains are the most common type of enrichment by 67% followed by plastic objects by 29.5%. Almost half of the farmers reported having no tail-biting problem on their farm, while 64.4% of the respondents have already tried at least once to raise pigs with intact tails. To reduce routine tail docking, it is essential to apply specific farm-oriented solutions effectively. To succeed in this aim, it is important to consider farmers’ concerns and practices. This study is the first step in that direction.
... Farm and abattoir based studies frequently report that male pigs are more likely to be the recipients of tail-biting (i.e., to have tail lesions) than female pigs irrespective of whether they are castrated (5,23,25) or entire (24,64,(92)(93)(94). However, Sinisalo et al. (22) found no difference between the sexes. ...
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Damaging behaviors (DB) such as tail and ear biting are prevalent in pig production and reduce welfare and performance. Anecdotal reports suggest that health challenges increase the risk of tail-biting. The prevalence of tail damage and health problems show high correlations across batches within and between farms. There are many common risk factors for tail-biting and health problems, notably respiratory, enteric and locomotory diseases. These include suboptimal thermal climate, hygiene, stocking density and feed quality. The prevalence of tail damage and health problems also show high correlations across batches within and between farms. However, limited evidence supports two likely causal mechanisms for a direct link between DB and health problems. The first is that generalized poor health (e.g., enzootic pneumonia) on farm poses an increased risk of pigs performing DB. Recent studies indicate a possible causal link between an experimental inflammation and an increase in DB, and suggest a link between cytokines and tail-biting. The negative effects of poor health on the ingestion and processing of nutrients means that immune-stimulated pigs may develop specific nutrient deficiencies, increasing DB. The second causal mechanism involves tail-biting causing poor health. Indirectly, pathogens enter the body via the tail lesion and once infected, systemic spread of infection may occur. This occurs mainly via the venous route targeting the lungs, and to a lesser extent via cerebrospinal fluid and the lymphatic system. In carcasses with tail lesions, there is an increase in lung lesions, abscessation, arthritis and osteomyelitis. There is also evidence for the direct spread of pathogens between biters and victims. In summary, the literature supports the association between poor health and DB, particularly tail-biting. However, there is insufficient evidence to confirm causality in either direction. Nevertheless, the limited evidence is compelling enough to suggest that improvements Boyle et al. Damaging Behavior and Disease to management and housing to enhance pig health will reduce DB. In the same way, improvements to housing and management designed to address DB, are likely to result in benefits to pig health. While most of the available literature relates to tail-biting, we suggest that similar mechanisms are responsible for links between health and other DB.
... Pigs that are subjected to tail biting experience pain and stress (6), and may require medical treatment and space allotment in hospital pens. Tail-biting behavior is therefore considered both an economic and a welfare challenge in modern pig farming (7,8). ...
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Automated monitoring of pigs for timely detection of changes in behavior and the onset of tail biting might enable farmers to take immediate management actions, and thus decrease health and welfare issues on-farm. Our goal was to develop computer vision-based methods to detect tail biting in pigs using a convolutional neural network (CNN) to extract spatial information, combined with secondary networks accounting for temporal information. Two secondary frameworks were utilized, being a long short-term memory (LSTM) network applied to sequences of image features (CNN-LSTM), and a CNN applied to image representations of sequences (CNN-CNN). To achieve our goal, this study aimed to answer the following questions: (a) Can the methods detect tail biting from video recordings of entire pens? (b) Can we utilize principal component analyses (PCA) to reduce the dimensionality of the feature vector and only use relevant principal components (PC)? (c) Is there potential to increase performance in optimizing the threshold for class separation of the predicted probabilities of the outcome? (d) What is the performance of the methods with respect to each other? The study utilized one-hour video recordings of 10 pens with pigs prior to weaning, containing a total of 208 tail-biting events of varying lengths. The pre-trained VGG-16 was used to extract spatial features from the data, which were subsequently pre-processed and divided into train/test sets before input to the LSTM/CNN. The performance of the methods regarding data pre-processing and model building was systematically compared using cross-validation. Final models were run with optimal settings and evaluated on an independent test-set. The proposed methods detected tail biting with a major-mean accuracy (MMA) of 71.3 and 64.7% for the CNN-LSTM and the CNN-CNN network, respectively. Applying PCA and using a limited number of PCs significantly increased the performance of both methods, while optimizing the threshold for class separation did result in a consistent but not significant increase of the performance. Both methods can detect tail biting from video data, but the CNN-LSTM was superior in generalizing when evaluated on new data, i.e., data not used for training the models, compared to the CNN-CNN method.
Background: Tail inspection in the abattoir is a tool to help determine the welfare status of pigs. However, methodologies vary widely. Moreover, meat inspection is moving from palpation and incision towards visual-only (VIS) examination. This study investigated whether a VIS examination was sufficient to detect tail damage compared to handling (HAND), which ensures examination of all aspects of the tail. Method: The severity of tail skin damage (0 [undamaged] - 4 [partial/full loss of tail]) and presence/absence of bruises was scored using both methods after scalding/dehairing of 5498 pig carcasses. Results: There was a good relationship between methods when evaluating tail skin damage (sensitivity, 82.48%; specificity, 99.98%; accuracy, 98.98%; correlation ρ = 0.84). The results were similar for the presence of bruises (sensitivity, 74.98%; specificity, 99.09%; accuracy, 89.94%; correlation ρ = 0.79). However, the percentage of tails classified as undamaged was higher using VIS (69.9%) than HAND (63.55%) examination. Conversely, VIS detected fewer mild lesions (score 1 - 13.64%; score 2 - 11.73%) than HAND (score 1 - 15.21%; score 2 - 15.53%). A higher percentage of bruises was detected using HAND than VIS (37.96% vs. 29.03%). Conclusions: Visual evaluation is a valid alternative to handling evaluation of carcass tail damage and bruising.
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Abstract Background Nowadays, body and tail lesions and respiratory disease are some of the greatest problems affecting the health and welfare of pigs. The aim of the study was to measure the prevalence of pleurisy, bronchopneumonia (enzootic pneumonia like lesions) and lesions on tail and body of heavy pigs subjected or not to tail docking through the inspection in Italian abattoirs. Additionally, the effect of tail docking and season was investigated on carcass quality (weight, % of lean meat, and Protected Designation of Origin (PDO) classification). For this purpose, a total 17.256 carcasses belonging to 171 batches from 103 farms were inspected in an Italian abattoir between 2019 and 2022. Enzootic pneumonia (EP) like lesions were scored according to the Madec and Derrien method, while pleurisy was scored using the Italian Slaughterhouse pleuritic evaluation system (SPES). For the tail and body, the lesions were scored according to Welfare Quality. The lesion score index (LSI) was calculated for each area. Data were analysed using a general linear model (GLM) including tail caudectomy, season and distance of the farm from the abattoir. Results The warm season increased the percentage of lesions in carcasses in all parts of the body observed (P
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Slaughterhouse workers are strategic capital for the meat industry in terms of operational and animal welfare issues; however, information about the attitudes of workers toward the human-animal relationship is limited. The main aim of our study was to identify the profiles of workers based on their attitudes toward pigs, occupational satisfaction, sociodemographics, and animal handling. The survey included 171 workers in 12 Colombian pig slaughterhouses. A factor analysis and a hierarchical cluster analysis identified four segments or worker profiles. The first comprised workers who relate to animals and their work in a mechanical way, the second comprised professional workers who are emotionally close to animals, the third comprised those committed to animals and their work, and the fourth comprised workers who are apathetic toward animals and work activity. The human-animal relationship at the slaughterhouse level is multifaceted, but is influenced by dependent on work satisfaction and sympathy toward the animals.
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Damage to the surface of the carcass after dehairing is a serious commercial problem, since it decreases the grade and subsequently the value of the carcass. In many countries, the incidence of skin damage on the carcass has not been considered to be a problem with high priority, as it seems to be easily solved by just trimming off the skin. However, the presence of an haematoma in the underlying tissue and its negative influence on meat quality must be taken into account. Some European Union (EU) countries are aiming at reducing the incidence of blemished carcasses in order to safeguard the image of the national pork sector for both domestic and exporting markets. Major factors responsible for the incidence of skin damage on the carcass are fighting among mixed groups of pigs and poor handling during the preslaughter stages. Recognition of the economical impact of these two factors on the slaughter pigs may lead to more welfare-friendly handling systems and to reduction in the practice of preslaughter mixing of animals.
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The present study assessed the association of tail-biting lesions in finishing pigs with weight gain, occurrence of locomotion or respiratory disorders and abscesses during finishing period, and carcass condemnation at slaughter. The study was carried out on 4 different farms. For each animal with a tail biting lesion, two control pigs were selected. The total number of animals in the study was 312, with 104 of them being tail-bitten. Tail lesions were classified according to the degree of severity into four scores: score 0 -normal tail withou lesion; score 1-3 - increasing lesion severity, and score 4 - healed lesions. Overall, the occurrence of severe tail lesions (score 3) varied from 55 to 73% of tail-bitten pigs among farms. On all farms, healing of tail lesions was observed in 95% to 100% of the animals at the evaluation performed within 41-43 days after the commencement of the study. In two out of the four evaluated farms, pigs with score of 3 showed lower weight gain (P
In comparison to 29 non bitten animals, severe tail biting was found to decrease the daily weight gain (DWG) by 25% in 8 fattening pigs during the period of biting. However, when comparing the weight gain of the lifetime between bitten and non bitten pigs, no influence of the tail biting was found. It is of interest that severity wounded pigs were parenterally treated with prokainpenicillin G for 3 consecutive days in connection with the tail biting, which could be suggested to promote the growth by reducing the influence of infections gained by the tail biting as well as of other infections present in herds rearing conventional pigs. Despite penicillin treatment, abscesses were more frequently recorded in tail bitten pigs than in non bitten animals. The tail biting was not equally distributed between the sexes, as barrows were more frequently bitten than gilts. Among the unbitten pigs, barrows were also found to grow faster than gilts. Indeed, when comparing tail bitten and non bitten barrows, a negative influence of tail biting on DWG was not only shown during the period of biting, but could also be monitored as a reduced DWG from that period until slaughter by 11% and during lifetime by 5% (the tail bitten gilts were too few to allow statistical calculations). These results clearly indicate that tail biting affects the growth rate of the lifetime despite penicillin treatment. However, it should be stressed that this decreased lifetime DWG may not be monitored when evaluating abattoir data because the sex distribution of the pigs may not be known in such materials.
IN BRIEF: Elbow and knee bursitis is common in both athletes and nonathletes and has three basic presentations: acute, chronic nonseptic, and chronic infected. Most acute swellings occur after trauma and can be treated with early aspiration, compression, and padding. Chronic, nonseptic bursitis can usually be treated with conservative therapy and, occasionally, aspiration or corticosteroid injection. Inflamed bursae should be aggressively evaluated and treated. Some may require aspiration and decompression, and oral or intravenous antibiotics should be started to prevent septicemia. Incision and drainage is rarely needed but may be indicated for injuries that do not respond. Surgical excision of the bursa is recommended only for recalcitrant cases.
The aim of this paper is to review existing literature concerning the impact of lameness and claw lesions on welfare, health and production of sows. When using the five freedoms, a common method to conceptualize animal welfare, to assess the impact of lameness, it appears that lameness as a single disease, may affect all of the freedoms. There is a wide variability with respect to the impact of claw lesions on welfare of sows, because only a proportion of animals are affected. Lameness affects welfare due to physically reduced locomotion ability, pain or general discomfort and sickness behavior. Cross-sectional studies show that the within-herd prevalence of sow lameness is quite high and may range from 8.8% to 16.9%. There are several reasons for lameness and claw lesions and they are very difficult to be identified during herd-level clinical examinations. Therefore, many researchers have studied the sows post-mortem and quite often found more than one lesion likely to cause lameness. Not all lesions are associated with lameness, but the location and severity of the lesions are important factors. Lameness can also affect the general health of the sow and predispose to loss of body condition, shoulder lesions and urogenital infections. Longevity of lame sows is decreased when compared with that of healthy-legged animals. Acutely and severely lame sows are removed immediately from the herd, and chronic, less severe lameness can affect the performance of sows and thus indirectly lead to culling. However, only few articles report about production or fertility figures of lame vs non-lame sows, except for ample data on longevity. In conclusion, lameness of sows is an important welfare and health problem and may also severely affect the profitability of sow herds.
Aggressive and sexual behaviour in entire males and females were studied on 408 pigs. The sum of aggressive interactions in the pen during routine feeding (ALP) was lowest in single-sex pens with females. ALP was higher at 132 than at 155 days. High ALP correlated with high average growth rate. Aggressive interactions in a competition test (IA) increased after slaughter of the three fastest-growing pigs in a pen (at 155 days), although the slaughtered pigs had initiated the most IA earlier (at 132 days). Entire male pigs displayed more sexual behaviour (mounting) than females. In 15% of entire males and 6% of females there were health problems specifically involving lameness or injured legs or feet. Five entire males and one female were euthanized in response to lameness or leg fracture. The rearing of entire male pigs may cause welfare problems, given their higher levels of aggression and sexual behaviour.