Assessment of lameness and claw lesions in sows

Dairy farmworkers' knowledge of the causes, risk factors, and clinical signs of bovine lameness

Background and Aim

Observing lameness in dairy cows is the primary animal-based indicator of their overall welfare and health status. The study evaluated dairy farmworkers' understanding of bovine lameness's causes, risk factors, and clinical symptoms in Kwa-Zulu Natal Province, South Africa.

Materials and Methods

Eleven dairy farms provided the data through questionnaires. The questionnaire consisted of five sections: The first section (A) gathered demographic data (age, gender, experience, level of study), and the second section (B) dealt with farm specifics (size, grazing method). Sections C, D, and E cover farm workers' knowledge of lameness risk factors, clinical signs of lameness, and treatment and management of lameness, respectively.

Results

About 85.5% of horses experience lameness during summer, contrasted to 15% during autumn. The seasonal results were statistically significant (p < 0.05). 93% of respondents identified a decrease in appetite as the most common sign of lameness, while 94% reported reduced milk yield and 90% increased lying time; a significant correlation was found between awareness of clinical signs and localities (p < 0.05). Age, gender, and occupation level (p < 0.05) were identified as contributing factors to the movement problem in the dairy industry, necessitating training for farm workers to enhance their knowledge.

Conclusion

Although there is a satisfactory (81%) understanding of lameness by farm workers. There is still need for improvement, hence, farm worker training and retraining are essential for managing and reducing the instances of bovine lameness.

Claw lesion status in Brazilian commercial sow herds from 2013 to 2023

Introduction

Claw lesions significantly contribute to lameness, greatly affecting sow welfare. This study investigated different factors that would impact the severity of claw lesions in the sows of Brazilian commercial herds.

Methods

A total of 129 herds (n = 12,364 sows) were included in the study. Herds were in the Midwest, Southeast, or South regions of Brazil. Inventory sizes were stratified into 250-810 sows, 811-1,300 sows, 1,301-3,000 sows, and 3,001-10,000 sows. Herds belonged to Cooperative (Coop), Integrator, or Independent structures. The herd management was conducted either maintaining breeds from stock on-site (internal), or through purchase of commercially available genetics (external). Herds adopted either individual crates or group housing during gestation. Within each farm, one randomly selected group of sows was scored by the same evaluator (two independent experts evaluated a total of 129 herds) from 0 (none) to 3 (severe) for heel overgrowth and erosion (HOE), heel-sole crack (HSC), separation along the white line (WL), horizontal (CHW) and vertical (CVW) wall cracks, and overgrown toes (T), or dewclaws (DC) in the hind legs after parturition. The study assessed differences and similarities between herds using Principal Component Analysis (PCA) and Hierarchical Agglomerative Clustering (HAC) analysis. The effects of factors (i.e., production structure, management, housing during gestation, and region) were assessed using the partial least squares method (PLS).

Results and discussion

Heel overgrowth and erosion had the highest prevalence, followed by WL and CHW, while the lowest scores were observed for T, DC, and CVW. Herds were grouped in three clusters (i.e., C1, C2, and C3). Heel overgrowth and erosion, HSC, WL, CHW, CVW, and T were decreased by 17, 25, 11, 25, 21, and 17%, respectively, in C3 compared to C1 and 2 combined. Independent structure increased the L-Index in all three clusters. Furthermore, individual housing increased the L-Index regardless of the cluster. The results suggest that shifting toward larger, more technologically advanced herds could potentially benefit claw health. Additionally, adopting group gestation housing appears to mitigate the adverse effects on claw health, although further validation is necessary, as Brazil has only recently transitioned from individual housing practices.

Deep learning pose detection model for sow locomotion

Lameness affects animal mobility, causing pain and discomfort. Lameness in early stages often goes undetected due to a lack of observation, precision, and reliability. Automated and non-invasive systems offer precision and detection ease and may improve animal welfare. This study was conducted to create a repository of images and videos of sows with different locomotion scores. Our goal is to develop a computer vision model for automatically identifying specific points on the sow's body. The automatic identification and ability to track specific body areas, will allow us to conduct kinematic studies with the aim of facilitating the detection of lameness using deep learning. The video database was collected on a pig farm with a scenario built to allow filming of sows in locomotion with different lameness scores. Two stereo cameras were used to record 2D videos images. Thirteen locomotion experts assessed the videos using the Locomotion Score System developed by Zinpro Corporation. From this annotated repository, computational models were trained and tested using the open-source deep learning-based animal pose tracking framework SLEAP (Social LEAP Estimates Animal Poses). The top-performing models were constructed using the LEAP architecture to accurately track 6 (lateral view) and 10 (dorsal view) skeleton keypoints. The architecture achieved average precisions values of 0.90 and 0.72, average distances of 6.83 and 11.37 in pixel, and similarities of 0.94 and 0.86 for the lateral and dorsal views, respectively. These computational models are proposed as a Precision Livestock Farming tool and method for identifying and estimating postures in pigs automatically and objectively. The 2D video image repository with different pig locomotion scores can be used as a tool for teaching and research. Based on our skeleton keypoint classification results, an automatic system could be developed. This could contribute to the objective assessment of locomotion scores in sows, improving their welfare.

Evaluating the Activity of Pigs with Radio-Frequency Identification and Virtual Walking Distances

Monitoring the activity of animals can help with assessing their health status. We monitored the walking activity of fattening pigs using a UHF-RFID system. Four hundred fattening pigs with UHF-RFID ear tags were recorded by RFID antennas at the troughs, playing devices and drinkers during the fattening period. A minimum walking distance, or virtual walking distance, was determined for each pig per day by calculating the distances between two consecutive reading areas. This automatically calculated value was used as an activity measure and not only showed differences between the pigs but also between different fattening stages. The longer the fattening periods lasted, the less walking activity was detected. The virtual walking distance ranged between 281 m on average in the first fattening stage and about 141 m in the last fattening stage in a restricted environment. The findings are similar to other studies considering walking distances of fattening pigs, but are far less labor-intensive and time-consuming than direct observations.

Welfare of pigs during transport

In the framework of its Farm to Fork Strategy, the Commission is undertaking a comprehensive evaluation of the animal welfare legislation. The present Opinion deals with protection of pigs during transport. The welfare of pigs during transport by road is the main focus, but other means of transport are also covered. Current practices related to transport of pigs during the different stages (preparation, loading/unloading, transit and journey breaks) are described. Overall, 10 welfare consequences were identified as highly relevant for the welfare of pigs during transport based on the severity, duration and frequency of occurrence: group stress, handling stress, heat stress, injuries, motion stress, prolonged hunger, prolonged thirst, restriction of movement, resting problems and sensory overstimulation. These welfare consequences and their animal-based measures are described. A variety of hazards were identified, mainly relating to factors such as mixing of unfamiliar pigs, inappropriate handling methods and devices, the use of pick-up pens, inexperienced/untrained handlers, structural deficiencies of vehicles and facilities, poor driving conditions, unfavourable microclimatic and environmental conditions and poor husbandry practices leading to these welfare consequences. The Opinion contains general and specific conclusions relating to the different stages of transport of pigs. Recommendations to prevent hazards and to correct or mitigate welfare consequences are made. Recommendations were also developed to define quantitative thresholds for microclimatic conditions and minimum space allowance within means of transport. The development of the welfare consequences over time was assessed in relation to maximum journey duration. The Opinion covers specific animal transport scenarios identified by the European Commission relating to transport of cull sows and 'special health status animals', and lists welfare concerns associated with these.

Occurrence of claw asymmetries in fattening pigs and potential impact on the development of sole ulcerations

Background

Claw abnormalities, particularly claw asymmetries, are associated with lameness in pigs and can be a welfare issue. However, the prevalence and development of claw asymmetries in pigs of different age is unknown. Therefore, the aim of this study was to analyze the claw symmetry over the pig lifetime from birth to slaughter as well as the occurrence of sole ulcerations in fattening pigs possibly caused by such asymmetric claws.

Results

From third day of life until slaughtering, asymmetric growth of the claws was detected more frequently and more severely with increasing age as determined by three-step scoring. Sole ulcerations were detected in slaughtered pigs only with a prevalence of 64.2% (197/307 examined animals). The risk for a sole ulceration was 3.6-fold higher for pigs with strongly asymmetric claws (≥ 30% size difference of the claw footing area) compared to slightly asymmetric claws (≥ 5–15% size difference of the claw footing area) (odds ratio (OR) = 3.6). It was even higher for pigs showing intermediately asymmetric claws (≥ 15–30% size difference of the claw footing area) (OR = 2.7).

Conclusions

The study showed a significant increase in the prevalence of claw asymmetries over the pigs’ lifetime, which can lead to serious pathologic findings with increasing age such as sole ulcerations. Most likely, the unbalanced weight load on single claws in combination with hard flooring can result in claw damages. Moreover, a genetic component cannot be excluded because claw asymmetries were already detected in suckling piglets.

Welfare of pigs on farm

This scientific opinion focuses on the welfare of pigs on farm, and is based on literature and expert opinion. All pig categories were assessed: gilts and dry sows, farrowing and lactating sows, suckling piglets, weaners, rearing pigs and boars. The most relevant husbandry systems used in Europe are described. For each system, highly relevant welfare consequences were identified, as well as related animal-based measures (ABMs), and hazards leading to the welfare consequences. Moreover, measures to prevent or correct the hazards and/or mitigate the welfare consequences are recommended. Recommendations are also provided on quantitative or qualitative criteria to answer specific questions on the welfare of pigs related to tail biting and related to the European Citizen's Initiative 'End the Cage Age'. For example, the AHAW Panel recommends how to mitigate group stress when dry sows and gilts are grouped immediately after weaning or in early pregnancy. Results of a comparative qualitative assessment suggested that long-stemmed or long-cut straw, hay or haylage is the most suitable material for nest-building. A period of time will be needed for staff and animals to adapt to housing lactating sows and their piglets in farrowing pens (as opposed to crates) before achieving stable welfare outcomes. The panel recommends a minimum available space to the lactating sow to ensure piglet welfare (measured by live-born piglet mortality). Among the main risk factors for tail biting are space allowance, types of flooring, air quality, health status and diet composition, while weaning age was not associated directly with tail biting in later life. The relationship between the availability of space and growth rate, lying behaviour and tail biting in rearing pigs is quantified and presented. Finally, the panel suggests a set of ABMs to use at slaughter for monitoring on-farm welfare of cull sows and rearing pigs.

Early Detection of Locomotion Disorders in Gilts Using a Novel Visual Analogue Scale; Associations with Chronic Stress and Reproduction

Locomotion scoring is crucial for the early detection of lameness, which reduces sow welfare and performance. Our objective was to test the effectiveness of a visual analogue scale (VAS) to measure locomotory ability (OVERALL) compared to a categorical scoring system (CAT) and to investigate associations with hair cortisol and reproductive performance. Locomotion was scored in gilts (n = 51) at service, on day 57 and day 108 of pregnancy, and at weaning, using a VAS (150 mm line: 0 mm (perfect)-150 mm (severely lame)), and a CAT (1 (perfect)-5 (severely lame)). Hair cortisol concentration was measured on day 108 of pregnancy. Reproductive performance data (parity 1-4) were acquired from farm records. VAS detected deviations from optimal locomotion more effectively than the CAT (F_3,145 = 2.70; p ≤ 0.05 versus F_3,195 = 2.45; p = 0.065). Higher OVERALL scores at service (REG = 0.003 ± 0.0012; F_1,48 = 4.25; p ≤ 0.05) and on day 57 (REG = 0.003 ± 0.0013; F_1,48 = 6.95; p ≤ 0.05) were associated with higher hair cortisol concentrations on day 108. Positive associations were detected between OVERALL at service and the number of piglets born dead (REG = 0.01 ± 0.006; F_1,36 = 4.24; p ≤ 0.05), and total born (REG = 0.1 ± 0.03; F_1,120 = 4.88; p ≤ 0.05). The VAS better facilitates early detection of lameness, which could help to prevent detrimental effects, possibly mediated by chronic stress, on reproductive performance.

The in-utero experience of piglets born from sows with lameness shapes their life trajectory

Experiences during gestation can alter the mother's behavior and physiology, thereby potentially affecting the behavioral and physiological development of the offspring. In livestock, one common challenge for pregnant animals is lameness: a multifactorial condition that causes pain, stress, resulting in poor welfare outcomes. Since maternal pain can affect offspring development, we aimed to quantify the behavioral response in 142 piglets born from sows with different degrees of lameness during pregnancy. Gait scores of 22 pregnant group-housed sows were assessed six times at 2-week intervals. Lameness scores varied from 0 (no lameness) to 5 (most severe lameness score). Saliva samples and behavior were assessed in the sows throughout pregnancy. Sows were moved to individual farrowing pens and placental tissue was collected for glucocorticoid assessment. At 28 days of age, piglets were weaned, weighed, and regrouped by body size and sex. Skin lesions were counted for each piglet on days 28, 29, and 30 after birth. During open field and novel object tests on day 30, the vocalization and activity levels were evaluated. Piglet data were grouped by the lameness score of the sows as G1 (without lameness), G2 (moderate lameness), and G3 (severe lameness). Data analysis included ANOVA or Kruskal-Wallis tests and pairwise comparisons which were performed using Tukey and Kramer (Nemenyi) test with Tukey-Dist approximation for independent samples. G2 piglets were heavier than G3 at weaning. G1 piglets had fewer skin lesions at days 28 and 29 than G2 piglets. Moreover, G1 piglets vocalized more than G2 when they were subjected to the combined open field and novel object test. We did not identify differences among sows showing different lameness scores in the concentration of placental or salivary glucocorticoids. Lameness in pregnant sows altered the offspring's weight gain, number of skin lesions and vocalizations, together showing evidence that lameness in sows affect offspring performance and behavior.

Feasibility and reliability of a German guideline for farm's self-monitoring in sows and piglets

The present study's aim was to test a German guideline for farm's self-monitoring in sows and piglets for its feasibility as well as its interobserver and test-retest reliability. The study was performed between September 2016 and April 2018 on 13 farrowing farms in Northern Germany. Contrary to the guideline, the testing was not carried out by the farmers themselves but by 2 observers with experience in pigs representing common farmers. For the interobserver reliability study, the observers performed 20 joint farm visits independently assessing the same animals. For the test-retest reliability study, each farm was visited 5 times by 1 observer (day 0, day 3, week 7, month 5, month 10). Farm visit 1 (day 0) was used as reference and compared with the remaining farm visits. The reliability was evaluated using Spearman's rank correlation coefficient (RS), intraclass correlation coefficient (ICC), and limits of agreement (LoA). As results, the guideline's feasibility was limited. The indicators' reliability also presented divergent results: All indicators in piglets revealed acceptable to good interobserver reliability (RS 0.64 to 0.77 ICC 0.33 to 0.48 LoA between the intervals -0.02 to 0.13 and -0.02 to 0.00). Contrarily, interobserver reliability was low for indicators in sows (e.g., claw alterations: RS -0.41 ICC 0.00 LoA -0.97 to 0.68). Overall acceptable test-retest reliability could be assigned to all indicators although no exact agreement existed but only the pursuit of trends is indicated. On the basis of the present results, the guideline in its present form cannot be recommended for farms' self-monitoring. Given the restricted applicability, it should be reconsidered whether it might not be more appropriate to use scientifically tested and generally accepted animal welfare assessment systems such as the Welfare Quality animal welfare assessment protocols, although their application is also time-consuming.

Rearing in female-only groups and dietary mineral supplementation improves sow welfare in the early parities and lifetime performance

The lifetime performance of commercial sows relies on longevity, which is dependent on good health and reproductive performance. However, there is a high rate of wastage of sows in the early parities, which is influenced by the way they are managed and housed during rearing. This study investigated the carry-over effect of gilt rearing strategy on the measures of welfare and performance. Eighty sows were reared using a two by two factorial design: rearing group composition [GC; female-only (FEM) or mixed-sex (MIX) from weaning] with or without supplementary minerals (CON = control diet; SUPP = control + Cu, Zn, and Mn) from 5 wk into the finisher stage. Once served, gilts were managed in a dynamic group gestation pen and fed a standard gestating sow diet. Locomotory ability was scored (0 to 5) and salivary cortisol measured five times during the first gestation, and human approach tests were carried out on day 108. Hooves were scored for injuries and legs for bursas at day 70 of the first gestation, at first weaning, and at the second farrowing. Sow behavior in the hoof scoring crate (movement, vocalization, and handling ease) was also recorded. The number of piglets born alive and dead during the first five parities was recorded as was the performance of the first litter to finish. Data were analyzed using general or generalized linear mixed models, as appropriate, using SAS (v 9.4). There was no effect (P > 0.05) of rearing treatment on locomotory ability, bursa score, the total number of piglets born, or on offspring growth. However, there was an interaction between GC and supplementary minerals (P < 0.05) on salivary cortisol levels with MIX × SUPP sows having the highest levels. Total hoof scores and heel erosion scores were higher in sows reared in MIX groups (P < 0.01), and CON sows tended to have higher horizontal crack scores (P = 0.06). Sows from MIX kicked more at weaning than FEM (P < 0.05) and tended to be more fearful in the forced human approach test (P = 0.1) where they are scored on their reaction to being approached. They also had more stillborn piglets across all five parities than FEM (P < 0.05). Overall, rearing replacement sows in FEM groups and dietary mineral supplementation had minimal but beneficial effects on their subsequent welfare and performance.

Large-Scale Phenotyping of Livestock Welfare in Commercial Production Systems: A New Frontier in Animal Breeding

Genomic breeding programs have been paramount in improving the rates of genetic progress of productive efficiency traits in livestock. Such improvement has been accompanied by the intensification of production systems, use of a wider range of precision technologies in routine management practices, and high-throughput phenotyping. Simultaneously, a greater public awareness of animal welfare has influenced livestock producers to place more emphasis on welfare relative to production traits. Therefore, management practices and breeding technologies in livestock have been developed in recent years to enhance animal welfare. In particular, genomic selection can be used to improve livestock social behavior, resilience to disease and other stress factors, and ease habituation to production system changes. The main requirements for including novel behavioral and welfare traits in genomic breeding schemes are: (1) to identify traits that represent the biological mechanisms of the industry breeding goals; (2) the availability of individual phenotypic records measured on a large number of animals (ideally with genomic information); (3) the derived traits are heritable, biologically meaningful, repeatable, and (ideally) not highly correlated with other traits already included in the selection indexes; and (4) genomic information is available for a large number of individuals (or genetically close individuals) with phenotypic records. In this review, we (1) describe a potential route for development of novel welfare indicator traits (using ideal phenotypes) for both genetic and genomic selection schemes; (2) summarize key indicator variables of livestock behavior and welfare, including a detailed assessment of thermal stress in livestock; (3) describe the primary statistical and bioinformatic methods available for large-scale data analyses of animal welfare; and (4) identify major advancements, challenges, and opportunities to generate high-throughput and large-scale datasets to enable genetic and genomic selection for improved welfare in livestock. A wide variety of novel welfare indicator traits can be derived from information captured by modern technology such as sensors, automatic feeding systems, milking robots, activity monitors, video cameras, and indirect biomarkers at the cellular and physiological levels. The development of novel traits coupled with genomic selection schemes for improved welfare in livestock can be feasible and optimized based on recently developed (or developing) technologies. Efficient implementation of genetic and genomic selection for improved animal welfare also requires the integration of a multitude of scientific fields such as cell and molecular biology, neuroscience, immunology, stress physiology, computer science, engineering, quantitative genomics, and bioinformatics.

Factors influencing claw lesion scoring in sows

Claw lesions have a multifactorial origin and may affect sow welfare and farm profitability. However, estimating the precise impact is hampered by several factors that interfere with the accuracy of claw lesion assessment. The objective of this study was to determine the impact of observer, scoring condition and claw cleanliness on claw lesion scoring in sows. The first experiment evaluated the impact of observer by calculating the inter- and intra-observer reliability during three test sessions using photographs. The second experiment evaluated the impact of observer, scoring condition (Feet First© chute of Zinpro Corp., "sow chute" vs. Mobile Claw Scoring Device, "MCSD"), and claw cleanliness (clean or soiled claws) on claw lesion scoring. For this experiment, 20 hybrid mid-gestating sows were hoisted up using the sow chute in which the MCSD was positioned. Lateral and medial claw digits of both hind claws were scored for heel horn erosion and separations along the heel/sole junction and white line. Scores were given by drawing a vertical bar on a 160 mm tagged visual analogue scale (tVAS); the severity of a claw lesion type was determined by measuring the distance from 0 mm. Four scores per sow were collected and analysed: clean claws × MCSD video recordings, soiled claws × MCSD video recordings, clean claws × visual scoring in a sow chute, and soiled claws × visual scoring in a sow chute. In both experiments, observer had an impact on the claw lesion scores. The inter-observer reliability was highest for overgrown dewclaws and lowest for the horizontal wall cracks (0.84 and 0.35, resp.). The highest intra-observer reliability was found for overgrown dewclaws and heel horn erosion (0.89) and lowest for vertical wall cracks (0.64). Furthermore, scoring condition and claw cleanliness influenced the scores in the second experiment and the limits of agreements were high (23.5-58.9 mm). The improved concordance correlation coefficient (iCCC) was highest for the heel horn erosion scores. In conclusion, the impact of observer seemed less relevant for claw lesion scoring; however, claw cleanliness and scoring condition were important and cannot be used interchangeably.

The Effect of Group Composition and Mineral Supplementation during Rearing on Measures of Cartilage Condition and Bone Mineral Density in Replacement Gilts

Lameness is a major cause of poor longevity and poor welfare in replacement gilts. The problem is exacerbated by inappropriate housing and diet during the rearing period. Replacement gilts are often reared with male finisher pigs destined for slaughter. If they are not castrated, they perform high levels of potentially injurious sexual and aggressive behaviour. Furthermore, finisher pig diets are not designed to meet the needs of developing gilts and may not supply the necessary minerals to support good limb health. The objective of this study was to evaluate the effect of supplementing the diet of replacement gilts with copper, zinc and manganese and separating them from males during the rearing period on locomotory ability, bone mineral density and cartilage lesion scores. A 2 × 2 factorial design experiment investigated the effect of female-only or mixed-sex rearing, with or without supplementary minerals (Copper, Zinc and Manganese). In total, 384 maternal line gilts were assigned to 32 pens of 12 and were locomotion scored during the rearing period. A sub-sample (n = 102) of gilts were culled at breeding age and the front right limb was removed at slaughter. Areal bone mineral density (aBMD) was measured using dual energy X-ray absorptiometry, after which the limb was dissected to score the condition of the cartilage. The addition of trace minerals to the diet resulted in increased aBMD in the humerus (P < 0.05) compared to the control diet. Rearing gilts in female-only groups reduced the number of cartilage lesions overall (P < 0.05), and on the humeral condyle (P < 0.05). Rearing replacement gilts in female-only groups and with mineral supplementation had benefits for limb health.

Deep Learning and Machine Vision Approaches for Posture Detection of Individual Pigs

Posture detection targeted towards providing assessments for the monitoring of health and welfare of pigs has been of great interest to researchers from different disciplines. Existing studies applying machine vision techniques are mostly based on methods using three-dimensional imaging systems, or two-dimensional systems with the limitation of monitoring under controlled conditions. Thus, the main goal of this study was to determine whether a two-dimensional imaging system, along with deep learning approaches, could be utilized to detect the standing and lying (belly and side) postures of pigs under commercial farm conditions. Three deep learning-based detector methods, including faster regions with convolutional neural network features (Faster R-CNN), single shot multibox detector (SSD) and region-based fully convolutional network (R-FCN), combined with Inception V2, Residual Network (ResNet) and Inception ResNet V2 feature extractions of RGB images were proposed. Data from different commercial farms were used for training and validation of the proposed models. The experimental results demonstrated that the R-FCN ResNet101 method was able to detect lying and standing postures with higher average precision (AP) of 0.93, 0.95 and 0.92 for standing, lying on side and lying on belly postures, respectively and mean average precision (mAP) of more than 0.93.

Addressing Lameness in Farmed Animals: An Urgent Need to Achieve Compliance with EU Animal Welfare Law

Simple Summary

In this short paper we explain the reasons why preventing and treating lameness in farmed animals can and should be considered a legal requirement under European Union (EU) animal welfare law. We also briefly present the situation in different farming sectors. We make the case that, in order to comply with current EU farmed animal welfare law, lameness prevalence and severity should be regularly monitored on farm, and species-specific alarm thresholds should be used to trigger corrective actions.

Abstract

Lameness is the clinical manifestation of a range of painful locomotory conditions affecting many species of farmed animals. Although these conditions have serious consequences for animal welfare, productivity, and longevity, the prevention and treatment of lameness continue to receive insufficient attention in most farming sectors across the European Union (EU). In this paper, we outline the legislative framework that regulates the handling of lameness and other painful conditions in farmed animals in the EU. We briefly outline the current situation in different livestock farming sectors. Finally, we make the case for the introduction of regular on-farm monitoring of lameness and for the setting of alarm thresholds that should trigger corrective actions.

On-Farm Claw Scoring in Sows Using a Novel Mobile Device

Claw lesions and lameness in sows are important problems in the industry as they impair sow welfare and result in economic losses. Available scoring techniques to detect claw lesions are all limited in terms of collecting data during all reproductive phases and recording all claws. The Mobile Claw Scoring Device (MCSD) was designed to address these limitations. After considering different practical situations and a design phase, two prototypes were constructed and tested. Improvements were incorporated into a final aluminium apparatus, consisting of two cameras with light-emitting diode (LED) lights mounted in a two-segment aluminium box and covered with laminated tempered glass plates. The operating system slides underneath the claws and takes video images. This final prototype was optimised and validated in an experiment with 20 hybrid sows, comparing scores for soiled claws using the MCSD against scores for clean claws using the Feet First^© sow chute (as gold standard). Fifty percent of the scores differed between both scoring tools, with mainly medial claw digits deviating, but this seemed biologically irrelevant. The MCSD seems to be an appropriate alternative for on-farm claw scoring and is distinguishable from other claw scoring techniques; however, it needs further optimisation to improve the similarity between the two techniques.

Effects of three husbandry systems on health, welfare and productivity of organic pigs

Organic pig husbandry systems in Europe are diverse - ranging from indoor systems with concrete outside run (IN) to outdoor systems all year round (OUT) and combinations of both on one farm (POUT). As this diversity has rarely been taken into account in research projects on organic pig production, the aim of this study was to assess and compare pig health, welfare and productivity in these three systems. Animal health and welfare were assessed using direct observation and records of 22 animal-based measures, comprising 17 health-, 3 productivity- and 2 behavioural measures. These were collected in pregnant sows, weaners and fattening pigs during direct observations and from records within a cross-sectional study on 74 farms (IN: n = 34, POUT: n = 28, OUT: n = 12) in eight countries. Overall, prevalence of several animal health and welfare issues was low (e.g. median 0% for pigs needing hospitalisation, shoulder lesions, ectoparasites; <5% for runts, tail lesions, conjunctivitis). Exceptions in particular systems were respiratory problems in weaners and fatteners (IN: 60.0%, 66.7%; POUT: 66.7%, 60.0%), weaning diarrhoea (IN: 25.0%), and short tails in fatteners (IN: 6.5%, POUT: 2.3%). Total suckling piglet losses (recorded over a period of 12 months per farm) were high in all three systems (IN: 21.3%; POUT: 21.6; OUT: 19.2%). OUT had lower prevalences of respiratory problems, diarrhoea and lameness of sows. POUT farms in most cases kept sows outdoors and weaners and fatteners similar to IN farms, which was reflected in the results regarding several health and welfare parameters. It can be concluded, that European organic pigs kept in all three types of husbandry system showed a low prevalence of health and welfare problems as assessed by our methodology, but respiratory health and diarrhoea should be improved in weaners and fatteners kept indoors and total piglet mortality in all systems. The results provide benchmarks for organic pig producers and organisations which can be used in strategies to promote health and welfare improvement. Furthermore, in future research, the identified health and welfare issues (e.g. suckling piglet mortality, weaning diarrhoea) should be addressed, specifically considering effects of husbandry systems.

Welfare Problems in Cattle, Pigs, and Sheep that Persist Even Though Scientific Research Clearly Shows How to Prevent Them

Poor production and handling practices continue to persist that are both detrimental to animal welfare and financially burdensome. These practices continue to persist for three reasons: (1) a segmented marketing chain where a producer is not held financially accountable for losses; (2) failure to measure and assess chronic painful problems such as lame livestock; and (3) repeating old mistakes, such as housing fattening cattle for long periods of time on bare concrete. Two examples of the first type of losses are bruises caused by poor handling and sick cattle at feedlots caused by failure to vaccinate and precondition weaned calves at the farm of origin. In some segmented marketing systems, there is no economic incentive to vaccinate. When the animals get sick, the responsibility gets passed to the next person. Buyers of meat products can reduce these "passed on" losses by source verification. The first step to reducing problems, such as lame livestock, is to measure the percentage of lame animals and work with the producers to reduce them. Also, transportation payments should be changed and contracts should be based on the condition of the animals at delivery.

Transportation of cull sows-a descriptive study of the clinical condition of cull sows before transportation to slaughter

Each year 500.000 sows, equal to 50% of Danish sows, are culled and transported to slaughter. However, the clinical condition, behavior, and welfare of cull sows have received almost no scientific attention. The aim of the current observational study was to describe the clinical condition of cull sows on the day of transportation to slaughter, including examination of possible differences between lactating and nonlactating sows. On the day of transportation, the participating farms were visited by trained technicians who conducted a thorough clinical examination of all sows selected by the farmer for slaughter. Four sows could not be transported because they were unfit according to the European Council Regulation regarding fitness for transportation, and they were not included in the present data. A total of 522 sows, with a median parity of 5 (range: 1-11), from 12 Danish farms were included in the study. Approximately, 10% showed signs of changed gait, and 0.8% were obvious lame. Wounds were observed in 54.6% of the sows, and 11% had decubital shoulder ulcers. Almost 40% of the cull sows were lactating. At culling, the lactating sows were of higher parity than the nonlactating sows, and lactating sows were at higher risk of having deviations from normal on clinical variables related to examination of the udder, such as udder swellings and inflammations. Nonlactating sows had 3.5 times more superficial skin lesions than lactating sows. Our findings warrant for further studies exploring different aspects of the life of cull sows in what is here defined as the The Cull Period, which is the interval from the culling decision is made until the sows are slaughtered.

Translational pain assessment: could natural animal models be the missing link?

Failure of analgesic drugs in clinical development is common. Along with the current "reproducibility crisis" in pain research, this has led some to question the use of animal models. Experimental models tend to comprise genetically homogeneous groups of young, male rodents in restricted and unvarying environments, and pain-producing assays that may not closely mimic the natural condition of interest. In addition, typical experimental outcome measures using thresholds or latencies for withdrawal may not adequately reflect clinical pain phenomena pertinent to human patients. It has been suggested that naturally occurring disease in veterinary patients may provide more valid models for the study of painful disease. Many painful conditions in animals resemble those in people. Like humans, veterinary patients are genetically diverse, often live to old age, and enjoy a complex environment, often the same as their owners. There is increasing interest in the development and validation of outcome measures for detecting pain in veterinary patients; these include objective (eg, locomotor activity monitoring, kinetic evaluation, quantitative sensory testing, and bioimaging) and subjective (eg, pain scales and quality of life scales) measures. Veterinary subject diversity, pathophysiological similarities to humans, and diverse outcome measures could yield better generalizability of findings and improved translation potential, potentially benefiting both humans and animals. The Comparative Oncology Trial Consortium in dogs has pawed the way for translational research, surmounting the challenges inherent in veterinary clinical trials. This review describes numerous conditions similarly applicable to pain research, with potential mutual benefits for human and veterinary clinicians, and their respective patients.

Transport Fitness of Cull Sows and Boars: A Comparison of Different Guidelines on Fitness for Transport

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Locomotion Disorders and Skin and Claw Lesions in Gestating Sows Housed in Dynamic versus Static Groups

Lameness and lesions to the skin and claws of sows in group housing are commonly occurring indicators of reduced welfare. Typically, these problems are more common in group housing than in individual housing systems. Group management type (dynamic versus static) and stage of gestation influence the behavior of the animals, which in turn influences the occurrence of these problems. The present study compared prevalence, incidence and mean scores of lameness and skin and claw lesions in static versus dynamic group housed sows at different stages of gestation during three consecutive reproductive cycles. A total of 10 Belgian sow herds were monitored; 5 in which dynamic groups and 5 in which static groups were utilized. All sows were visually assessed for lameness and skin lesions three times per cycle and the claws of the hind limbs were assessed once per cycle. Lameness and claw lesions were assessed using visual analogue scales. Static groups, in comparison with dynamic groups, demonstrated lower lameness scores (P<0.05) and decreased skin lesion prevalence (24.9 vs. 47.3%, P<0.05) at the end of gestation. There was no difference between treatment group regarding claw lesion prevalence with 75.5% of sows demonstrating claw lesions regardless of group management. Prevalences of lameness (22.4 vs. 8.9%, P<0.05) and skin lesions (46.6 vs. 4.4%, P<0.05) were highest during the group-housed phase compared to the individually housed phases. Although the prevalence of lameness and skin lesions did not differ three days after grouping versus at the end of the group-housing phase, their incidence peaked during the first three days after moving from the insemination stalls to the group. In conclusion, the first three days after grouping was the most risky period for lameness incidence, but there was no significant difference between static or dynamic group management.

Automatic detection of lameness in gestating group-housed sows using positioning and acceleration measurements

Lameness is an important issue in group-housed sows. Automatic detection systems are a beneficial diagnostic tool to support management. The aim of the present study was to evaluate data of a positioning system including acceleration measurements to detect lameness in group-housed sows. Data were acquired at the Futterkamp research farm from May 2012 until April 2013. In the gestation unit, 212 group-housed sows were equipped with an ear sensor to sample position and acceleration per sow and second. Three activity indices were calculated per sow and day: path length walked by a sow during the day (Path), number of squares (25×25 cm) visited during the day (Square) and variance of the acceleration measurement during the day (Acc). In addition, data on lameness treatments of the sows and a weekly lameness score were used as reference systems. To determine the influence of a lameness event, all indices were analysed in a linear random regression model. Test day, parity class and day before treatment had a significant influence on all activity indices (P<0.05). In healthy sows, indices Path and Square increased with increasing parity, whereas variance slightly decreased. The indices Path and Square showed a decreasing trend in a 14-day period before a lameness treatment and to a smaller extent before a lameness score of 2 (severe lameness). For the index acceleration, there was no obvious difference between the lame and non-lame periods. In conclusion, positioning and acceleration measurements with ear sensors can be used to describe the activity pattern of sows. However, improvements in sampling rate and analysis techniques should be made for a practical application as an automatic lameness detection system.

Osteochondrosis, but not lameness, is more frequent among free-range pigs than confined herd-mates

BACKGROUND

Organic pig production is expanding and amongst the objectives of organic farming are enhancing animal health and welfare. However, some studies have reported a higher prevalence of lameness and joint condemnation at slaughter in free-range/organic pigs than in conventionally raised pigs. Organic slaughter pigs have free-range housing in which indoor and outdoor access is compulsory, while in conventional farming the pigs are commonly confined to indoor pens. The present study evaluated the effects of free-range and confined housing on lameness prevalence in a herd of 106 finisher pigs, and whether osteochondrosis and Erysipelothrix rhusiopathiae associated arthritis influences these effects. We also evaluated the association between clinical lameness during the rearing period and joint condemnations at slaughter.

RESULTS

Seventy free-range and 36 confined housed fattener pigs were scored for their gait twice during the rearing period and 848 joints were evaluated post mortem. Osteochondrosis was more frequent among free-range than confined pigs (P < 0.05), and when present it was also more severe (P < 0.001). Pigs with more numerous and more severe osteochondral lesions had their gait affected more than did pigs with fewer such lesions (P < 0.05). Hence it was a paradox that we did not detect more lameness among the free-range pigs than the confined pigs. E. rhusiopathiae associated arthritis was not diagnosed. The association between gait remarks/clinical lameness and joint condemnations at slaughter was not significant.

CONCLUSIONS

The results indicate that free-range housing may have both positive and negative effects on locomotory traits. Free-range pigs may be less clinically affected by osteochondrosis than are confined pigs. One explanation for this effect may be strengthening of joint supportive tissue and pain relief promoted by exercise. Visual gait scoring missed serious joint lesions that probably were harmful to the pigs, and should therefore not be used as a sole indicator of joint/leg health in welfare inspection of pigs. The association between gait scores and joint condemnation appeared to be poor. This study was limited to one herd, and so more and larger studies on the effects of free-range housing on lameness severity and osteochondrosis development in pigs are recommended.

Effect of locomotion score on sows' performances in a feed reward collection test

Sows housed in groups have to move through their pen to fulfil their behavioural and physiological needs such as feeding and resting. In addition to causing pain and discomfort, lameness may restrict the ability of sows to fulfil such needs. The aim of our study was to investigate the extent to which the mobility of sows is affected by different degrees of lameness. Mobility was measured as the sow's willingness or capability to cover distances. Feed-restricted hybrid sows with different gait scores were subjected to a feed reward collection test in which they had to walk distances to obtain subsequent rewards. In all, 29 group-housed sows at similar gestation stage (day 96.6 ± 7 s.d.) were visually recorded for gait and classified as non-lame, mildly lame, moderately lame or severely lame. All sows received 2.6 kg of standard commercial gestation feed per day. The test arena consisted of two feeding locations separated from each other by a Y-shaped middle barrier. Feed rewards were presented at the two feeders in turn, using both light and sound cues to signal the availability of a new feed reward. Sows were individually trained during 5 non-consecutive days for 10 min/day with increasing barrier length (range: 0 to 3.5 m) each day. After training, sows were individually tested once per day on 3 non-consecutive days with the maximum barrier length such that they had to cover 9.3 m to walk from one feeder to the other. The outcome variable was the number of rewards collected in a 15-min time span. Non-lame and mildly lame sows obtained more rewards than moderately lame and severely lame sows (P<0.01). However, no significant difference was found between non-lame and mildly lame sows (P=0.69), nor between moderately lame and severely lame sows (P=1.00). This feed reward collection test indicates that both moderately lame and severely lame sows are limited in their combined ability and willingness to walk, but did not reveal an effect of mild lameness on mobility. These findings suggest that moderately and more severely lame sows, but not mildly lame sows, might suffer from reduced access to valuable resources in group housing systems.

Pre-clinical and clinical walking kinematics in female breeding pigs with lameness: A nested case-control cohort study

Gait profiles were investigated in a cohort of female pigs experiencing a lameness period prevalence of 29% over 17 months. Gait alterations before and during visually diagnosed lameness were evaluated to identify the best quantitative clinical lameness indicators and early predictors for lameness. Pre-breeding gilts (n= 84) were recruited to the study over a period of 6 months, underwent motion capture every 5 weeks and, depending on their age at entry to the study, were followed for up to three successive gestations. Animals were subject to motion capture in each parity at 8 weeks of gestation and on the day of weaning (28 days postpartum). During kinematic motion capture, the pigs walked on the same concrete walkway and an array of infra-red cameras was used to collect three dimensional coordinate data of reflective skin markers attached to the head, trunk and limb anatomical landmarks. Of 24 pigs diagnosed with lameness, 19 had preclinical gait records, whilst 18 had a motion capture while lame. Depending on availability, data from one or two preclinical motion capture 1-11 months prior to lameness and on the day of lameness were analysed. Lameness was best detected and evaluated using relative spatiotemporal gait parameters, especially vertical head displacement and asymmetric stride phase timing. Irregularity in the step-to-stride length ratio was elevated (deviation  ≥ 0.03) in young pigs which presented lameness in later life (odds ratio 7.2-10.8).