Many piglets are exposed to potentially painful husbandry procedures within the first week of life, including tail docking and castration, without the provision of either anaesthesia or analgesia. The assessment methods used to evaluate pain experienced by piglets are often affected by low specificity and practical limitations, prompting the investigation of alternative methodologies. The assessment of changes in facial expression following a painful event has been successfully applied to several species. The objective of this pilot study was to evaluate the utility of a Grimace Scale applied to neonatal pigs to evaluate pain evoked by tail docking and castration. Eight female piglets, sus scrofa domesticus (Landrace/Large White X synthetic sire line) underwent tail docking and 15 male piglets (75% Large White and 25% Belgian Landrace) were exposed to the castration procedure. Clear images of the faces of the piglets were collected immediately pre- and post-procedure. The images were used by experienced observers to identify Facial Action Units (FAU) which changed in individuals over this period and a scoring scale was depicted in a training manual. A set of randomly selected images were then combined in a scorebook, which was evaluated after training by 30 scorers, blind to the treatment. The scale for most FAU was used with a high level of consistency across all observers. Tail docking induced a significant change (P<0.05) only in the ‘orbital tightening’ Action Unit, whereas no change in any unit was observed in castrated piglets. In this initial stage of development, orbital tightening at least seems to have the potential to be applied to investigate painful conditions in neonatal pigs. Nonetheless, more studies are needed to assess its full effectiveness and to evaluate the influence of possible confounds (e.g. handling stress) on the observed changes in facial expressions.

In order to evaluate at the slaughterhouse external carcass lesions on heavy pigs (170 kg) as potential welfare indicators, and the prevalence of ham defects determining ham exclusion from Protected Designation of Origin (PDO) markets, 732 pig batches from northern Italy were monitored during a 12-month period, and then processed analysing the effect of slaughter season, overnight lairage, and production type. On the slaughter line, skin scratches were separately scored in the posterior region (defined as the area including the hind legs and the tail) and the anterior one (as the remaining area), while the whole carcass was examined for external hematomas. Chronic ear and tail lesions referable to the rearing phase, and bursitis were recorded as retrospective welfare indicators. The annual median prevalence of carcasses per batch with severe anterior scratches was 64% while 46.4% had severe posterior scratches. The highest autumn score for both skin scratches (P < 0.001) and traumatic ham defects (P = 0.005) is reflected in the positive correlation between severe posterior scratches and ham hematomas (r² = 0.27; P < 0.001). Overnight lairage batches resulted in higher prevalence for scratches, while among ham defects only veining increased. Among binary records, only ear lesions were frequently recorded (annual median = 10%). A comparison analysis between pigs in and out of PDO circuit was performed to evaluate the variation related to the different genetics, showing differences for ear and tail lesions and for almost all the considered ham defects. The present study confirms that skin lesions represent a problem also for heavy pigs and that overnight lairage and season can affect their prevalence, with the associated possibility to give ham defects. Ear lesions are suitable to be used as retrospective welfare indicator, while tail lesions usage is nowadays limited by the extensive use of tail docking.

In livestock, the importance of hygiene management is gaining importance within the context of biosecurity. The aim of this study was to monitor the implementation of biosecurity and hygiene procedures in 20 swine herds over a 12-month period, as driven by tailor-made plans, including training on-farm. The measure of adenosine triphosphate (ATP) environmental contents was used as an output biomarker. The presence of livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) and extended-spectrum β-lactamase producing Escherichia coli (ESBL-E. coli) was also investigated as sentinels of antibiotic resistance. A significant biosecurity improvement (p = 0.006) and a reduction in the ATP content in the sanitised environment (p = 0.039) were observed. A cluster including 6/20 farms greatly improved both biosecurity and ATP contents, while the remaining 14/20 farms ameliorated them only slightly. Even if the ESBL-E. coli prevalence (30.0%) after the hygiene procedures significantly decreased, the prevalence of LA-MRSA (22.5%) was unaffected. Despite the promising results supporting the adoption of tailor-made biosecurity plans and the measure of environmental ATP as an output biomarker, the high LA-MRSA prevalence still detected at the end of the study underlines the importance of improving even more biosecurity and farm hygiene in a one-health approach aimed to preserve also the pig workers health.