Introduction: Tail biting is a widespread problem in pig production systems and has a negative impact on both animal welfare and farm income. This explorative study aims to validate how tail biting is related to general behaviors at the individual level and explore whether these behaviors are related to a particular type of tail biting: two-stage, sudden-forceful, obsessive, or epidemic.Methods: This research was conducted in a standard commercial setting where 89 tail-docked pre-finishing piglets divided into 8 groups were observed 4 days per week from 5 to 8 weeks of age. Each piglet was observed for a total of 160 min using continuous focal sampling. Ten individual behaviors were recorded based on the general behaviors expected to be linked to giving tail biting (PCA1), receiving tail biting (PCA2), and tail biting damage (PCA3). These PCAs were assembled and related to tail biting given, tail biting received, and tail biting lesions.Results: Tail biting did not lead to major damage on the piglets' tail at 8 weeks of age but was observed 420 times, where most of the individuals (72%) were categorized as “biters and victims.” When relating PCA1 with tail biting given, piglets that gave more tail biting showed more “active exploration.” When relating PCA2 with tail biting received, piglets receiving more tail biting were more “explored while active” and “attacked and explored.” When relating PCA2 with tail biting lesions, piglets presenting lesions showed more “agonism.” Surprisingly, tail biting lesions were not significantly related to PCA3. The relationship between explorative behaviors and tail biting indicates that the pre-damage stage of two-stage tail biting was the predominant tail biting type, while the damaging stage was likely incipient. The relationship between tail biting and aggression, as well as the minor tail lesions observed suggest that sudden-forceful tail biting was probably present even though it was rarely seen. Obsessive and epidemic tail biting were not observed.Discussion: This study demonstrates that studying tail biting at the individual level helps to identify the type of tail biting present. This gives directions to farmers for applying appropriate measures to prevent the development of tail biting behavior in piglets.

Organic livestock farming is committed to high environmental and animal welfare standards, although pathologies such as post-weaning diarrhoea (PWD) may appear. The main objective of this study was to assess nutritional strategies to prevent PWD in organic piglets. A total of 134 weaned piglets were fed one of three diets: high crude protein (17.8%, HCP), low crude protein (16.8%, LCP), and low crude protein supplemented with liquid whey (LCP+W). Piglets were assessed weekly for four weeks on the following parameters: diarrhoea incidence, additional health parameters, average daily gain, and behaviour. Faecal samples were taken to analyse the intestinal microbiota composition. Data were analysed using LMM and GLMM models and Shannon and Whittaker indexes. No significant effect of diet on diarrhoea incidence was found, but the LCP+W diet increased average daily gain. Pigs fed the LCP+W diet presented a lower percentage of drinking and negative social behaviour compared with the HCP diet, and LCP pigs presented higher exploration compared with HCP. In addition, LCP+W piglets showed a higher abundance of the beneficial genus Frisingicoccus. Although liquid whey did not reduce diarrhoea incidence, the benefits found in growth, microbiota composition, and reduced negative social behaviour indicate that it could be an optimal supplement to organic diets.

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

High levels of social stress are known to negatively impact pig welfare. The aim of this study was to evaluate the impact of social stress in growing–finishing pigs by measuring serum metabolome changes and saliva biomarkers. Seventy-two undocked pigs (thirty-six males and thirty-six females) were housed in single-sex pens of four, with the second dominant pig in each pen selected as the focal pig. A social challenge was conducted by mixing the focal pig with three new pigs in its home pen on two consecutive days on trial days 62–64. Saliva and blood samples were collected, and the pigs’ behaviour and body lesions were evaluated pre- and post-challenge. A total of 630 serum metabolites were analysed, 292 of which could be statistically compared using Biocrates WebIDQ v5 software. Salivary haptoglobin concentrations and the number of body lesions significantly increased after the challenge (p < 0.001), whereas the average daily weight gain decreased (p < 0.05). The serum showed decreases in essential amino acids (Thr, Met, and Phe), non-essential amino acids (Glu, Asn, Asp, Pro, and Tyr), betaine, ornithine, indoxyl sulphate, taurine, and some blood di- and triacylglycerols (q < 0.05), and increases in oleic, eicosanoic, eicosadienoic, and dihomo-gamma-linolenic acids; EPA; and DHA post-challenge (q < 0.05). Overall, the results suggest the potential of metabolomics as a tool providing a more holistic view of the impact of social stress.

The viability of raising pigs from weaning to slaughter with inorganic phosphorus (iP)-free diets using a hybrid 6-phytase was tested in two trials. Three experimental diets were formulated: T1, a control diet with monocalcium phosphate (MCP); T2, a diet without MCP + phytase (P and Ca phytase matrix formulation); and T3, a diet without MCP + phytase (P, Ca + extra nutrients in a phytase matrix formulation). Rapeseed and sunflower meal were used in addition to soybean meal as protein sources, in order to increase the phytate-P content. Performance was monitored from weaning to slaughter, and bones were sampled at the slaughterhouse to test for bone mineralization. In the second trial, gait scores were also assessed at 75, 110, and 134 days. Weight gain was not significantly affected by treatment in either trial. However, in Trial 1, males receiving T2 had a reduced overall feed efficiency than males receiving T1, whereas in Trial 2, a reduced overall feed efficiency was observed for T3 relative to T2 (p < 0.05), probably due to the extra nutrient reduction. No differences in bone mineralization or gait score were observed. In conclusion, it is possible to raise pigs without iP by using phytase in feeds containing phytate-P. This may contribute to more sustainable pig production with reduced P excretion and lower usage of rock phosphate, a limited resource.