Summary
Note: 42 piglets were euthanized after the study (the piglets randomly selected for histo-pathology examinations), but we chose to summarize the study as it provides insight into pig welfare. Tail necrosis and inflammation is one of the largest problems in pig farming and impairs pig welfare. 146 piglets were examined two hours after birth and none of the piglets were completely healthy. Over 80% had inflammation or necrosis of the tail, and 60% of piglets were affected in other body parts such as the coronary bands, teats, face, and ears. 42 piglets were selected for histo-pathology examinations and all showed alterations in the tail base. A limitation to this study is the litters used were the mothers 3rd-7th litter, and using a first litter could have provided clearer results. A strength of this study is the naturalistic setting (i.e., selecting pigs from an active pig farm). This study highlights that even at birth, piglets in the food system demonstrate compromised health. Further, it suggests that there are other reasons that need to be further studied as causes for necrosis of body parts other than biting or mechanical irritation.
Inflammation and loss of tail integrity can be reasons for serious impairment of animal welfare and one of the major challenges facing modern pig farming. Evidence from practice increasingly suggests that tail lesions might be caused not only by tail biting but also by inflammation and necrosis, which can occur without any action from other pigs. Such changes are not limited to the tail but can also be observed in the ears, heels and soles, claw coronary bands, teats, navel, vulva and face. To describe inflammatory and necrotic manifestations in newborn piglets, all 146 piglets from 11 sows were clinically examined not later than 2 h after birth. In addition, the tail base of 30 randomly selected piglets out of the 146 was histo-pathologically examined as one of the most conspicuously affected body parts. Over 80% of the newborns showed affections in the tail base, claw wall and heels. In 65–87% of the animals, the coronary bands, teats, the face and the ears were affected. None of the 146 piglets was completely free from pathological manifestations. On average, the piglets were affected in six out of nine body parts simultaneously. Histological examinations showed that clear alterations in the skin were already manifested around the time of birth in all examined piglets. Alterations were characterised by the occurrence of numerous lymphocytes and granulocytes throughout the entire subepithelial connective tissue, predominantly in perivascular and perifollicular localisation but also within directly subepithelial glandular ducts and diffusely within the subepithelial connective tissue. In the majority of individuals, the epithelial structure was intact. This concurrence of symptoms in the newborns indicates a primarily endogenous aetiology of an inflammation and necrosis syndrome. Further studies in diverse herd contexts are necessary to establish the conditions for the emergence of such a syndrome and develop welfare indicators.