BACKGROUND: Ear and tail lesions are prevalent indicators of impaired welfare observed in pig production with different multifactorial causes. Understanding the progression of ear and tail lesions over time is important to implement preventative strategies on commercial pig farms. Therefore, this case study aimed to provide a detailed account of patterns of ear and tail lesions in pigs on a single commercial farm during the grower-finisher period.
METHODS: A total of 1,676 12-week old pigs (n = 773 females and n = 903 males, all tail docked) were followed from arrival to the grower facilities until transferred to the finisher stage on a commercial pig farm in Ireland. Pigs were individually weighed and inspected for the severity of fresh ear and tail lesions (score 0-4) on transfer to the first grower (24.9 ± 5.33 kg, 12 weeks of age, n = 1,676 pigs), second grower (33.3 ± 7.04 kg, 14 weeks of age, n = 1,641 pigs), and finisher stage (60.2 ± 7.74 kg, 18 weeks of age, n = 1,626 pigs). Due to the low number of pigs with high scores, ear lesions were classified as no (score 0), mild (score 1), moderate (score 2) and severe (score ≥ 3) and tail lesions were classified as no (score 0), mild (score 1), and moderate-to-severe (score ≥ 2). Ear lesions were more prevalent than tail lesions at each inspection. There were approx. 19% of pigs with ear lesions at all three inspections but no pigs presented with tail lesions at all three inspections. When considering the specific severity categories, we observed 32 different ear lesion score combinations and 15 different tail lesion score combinations across the three inspections.
CONCLUSIONS: The high number of observed patterns of ear and tail lesions suggest large individual variability in lesion progression. Ear lesions were more of an issue than tail lesions and little is known about this health and welfare problem indicating that further research into causes and management strategies is needed.

BACKGROUND: Porcine ear necrosis (PEN) in pigs is characterized by a blue to black discoloration of the tip or margin of the ear followed by necrosis. The present study investigated the prevalence of PEN in a Belgian pig farm with PEN problems in nursery pigs, the effect of a mycotoxin detoxifier added to the feed on PEN prevalence, and the impact of PEN on the piglets\' growth. Six consecutive batches of weaned piglets [565-751 piglets per batch, (n = 3898)] were included. For each weaning batch, the presence and severity of PEN during the nursery period (3-10 weeks of age) were recorded weekly. Average daily gain (ADG) was calculated by weighing 597 individual piglets divided over the six batches. Additionally different mycotoxins were measured in the feed using LC-MS/MS analysis, and to three randomly selected batches, a mycotoxin detoxifier (Mycofix® Plus 5E, Biomin) was added to the feed.
RESULTS: At the end of the nursery period, 11.0-32.0% of the piglets in each batch were affected. The prevalence increased with the number of weeks post-weaning, especially from week 4 after weaning onwards. Mild, moderate, severe and very severe lesions represented 84.6%, 14.0%, 1.3% and 0.1% of all lesions, respectively. Different mycotoxins were present in the feed, but all at low concentrations. The mean ADG (± SD) for pigs without (n = 243) and with (n = 158) lesions was 391 g (± 71 g) and 394 g (± 65 g), respectively (P > 0.05). The ADG for mildly affected (387 g ± 68 g) and moderately affected piglets (420 g ± 44 g) was not significantly different (P > 0.05). The PEN prevalence in the batches without or with the mycotoxin detoxifier was 25% and 22%, respectively (P > 0.05).
CONCLUSIONS: Twenty-three percent of animals showed lesions at the end of the nursery. Affected pigs did not have a lower ADG compared to non-affected animals, which might be explained by the fact that most affected piglets only had mild lesions. The addition of a mycotoxin detoxifier did not influence the prevalence of PEN, possibly because of the low levels of mycotoxin contamination. Further research is warranted to assess the impact of more severe PEN lesions and the effect of control measures.

Hemangiomas are commonly encountered benign vascular tumors in clinical practice. They are easily diagnosed clinically, but it is essential to know atypical and rare varieties of these tumors to avoid confusing them with vascular malformations. The traditional approach in managing hemangiomas has been a \"wait and watch\" policy as most of these lesions undergo spontaneous regression with time. There are multiple treatment modalities in managing these lesions, but with specific indications for each of them. We report a case of Nicolau syndrome following injection sclerotherapy for a residual ear hemangioma, which lead to necrosis and total loss of skin and cartilage. However, the full-thickness defect in the ear was restored with a composite temporalis fascial flap, conchal cartilage graft, and split skin graft reconstruction. A detailed literature review of the presentation and management of this vascular tumor is discussed with a special emphasis on avoiding complications and maximizing patient outcomes.

Porcine ear necrosis (PEN) is a condition that mainly occurs in intensive pig production systems and mostly affects piglets after weaning. The syndrome manifests itself with lesions on the pinna, which can heal or become more severe resulting in partial loss of the ear. The pathogenesis of the condition is not fully known. Three different hypotheses for the development of PEN are described in this review: (1) damage of the epidermis due to Staphylococcal exfoliative toxins; (2) occlusion of small blood vessels; and (3) ear biting with subsequent β-hemolytic streptococcal infection. Risk factors have not been completely elucidated, but viral and bacterial infections, and husbandry factors such as environment, housing conditions and management, have been suggested. It is also possible that some cases are due to a combination of these factors. The role of parasitic infestations has been not investigated. Due to bacterial involvement, severely affected pigs can be treated with antimicrobials. Control and preventive measures should focus on reducing potential risk factors by implementing herd immunization, as well as improvement of sanitary conditions, feed quality (with respect to mycotoxin contamination), management (appropriate stocking density), and environmental conditions (e.g. number of drinkers and feeders and/or optimal ventilation). Further research is needed to better understand the precise etiology and pathogenesis of PEN, so that risk factors can be identified and more targeted control measures can be implemented.

The aim of this pilot study was to develop and evaluate an automated system for the assessment of ear and tail lesions as welfare indicators in pigs at the abattoir. A camera-based system was constructed to enable automatic assessment. This was evaluated in comparison to a standard observer, defined as skilled human veterinary observer, based on 5952 carcasses. We detected significant values for ear lesions (sensitivity, 77.0; specificity, 96.5; accuracy, 95.4%) and good values for tail lesions (sensitivity, 77.8%; specificity, 99.7%; accuracy, 99.5%). The reliabilities of assessments by four individual human observers directly at the abattoir and the camera system were calculated using Krippendorff\'s alpha. These varied between 0.42 and 0.67 for ear lesions and 0.42 and 0.55 for tail lesions, while better values were reached for the agreement between the system and picture-based evaluation (0.64 for ear lesions and 0.75 for tail lesions). More scientific evaluations at different abattoirs are now needed to further test and improve the camera-based system and its various scopes of application.

Ear necrosis is a syndrome affecting pigs shortly after weaning and is regarded as an animal welfare issue. The etiology is unknown but Treponema spp., predominantly Treponema pedis, are commonly detected in the lesions. Oral treponemes have been suggested as source of infection, transferred by biting and licking behavior. In this study, five pigs were intradermally inoculated with Treponema pedis strain T A4 with the aim of investigating if this strain would induce ear lesions. Three pigs served as controls. The inoculation was repeated after 29 days, and the study continued for 56 days. Serum samples were collected throughout the study and analyzed by ELISA for IgG antibodies towards T. pedis T A4 lysate. Skin biopsies were taken from the inoculation area at the end of the study. Gingival samples were collected and cultivated for treponemes, for comparison to the inoculation strain and to follow colonisation. The challenged pigs did not develop any clinical signs of infection and no spirochetes were detected in sections from skin biopsies. The number of Treponema-positive gingival samples increased during the study. In the challenge group, IgG towards the bacterial lysate peaked 7 days after each inoculation and decreased rapidly hereafter. In the control group a weak IgG response was observed after the second inoculation, possibly caused by the oral treponemes.

Porcine necrotic ear syndrome (PNES) in pigs has been reported as an increasing health problem in many countries with intensive pig farming. The etiology of this disease is complex and the presumed triggering factors can be divided into infectious and non-infectious agents. The present report describes a case of Porcine Circovirus type 2 (PCV2), infection associated with lesions of PNES at the weaning stage of a farrow-to-finish pig farm. Approximately 35% of weaners (1-3 weeks after weaning) presented clinical symptoms similar to Post-weaning Multisystemic Wasting Syndrome (PMWS). About 2-3 weeks after weaning the first lesions of PNES occurred in approximately 20% of pigs, resulting in a significant health problem characterized by poor growth or severe wasting and finally mortality up to 15% in some batches. Moreover, approximately 5% of survived weaners, during growing / finishing stage, presented poor growth and secondary co-infections that lead to death. The present study based on the clinical signs, serological and pathological examinations, indicates that weaners suffered by sub-acute PCV2 infection resulting in PMWS associated with PNES. The lesions of PNES were initially observed at the same period (4-8 weeks of age) with the higher seroprevalence of PCV2 infection. Metaphylaxis of this case included intramuscular injection of florfenicol for the treatment and control of skin lesions and respiratory signs. Moreover, piglets were vaccinated against PCV2. In conclusion, sub-acute PCV2 infection could be included in triggering factors PNES in weaners. The mass vaccination against PCV2 of infected piglets might be effective in reduction of clinical signs and losses of PNES in cases of PCV2 infection associated with PNES.

Skin lesions often seen in pig production are of great animal welfare concern. To study the potential role of Treponema bacteria in porcine skin ulcers, we investigated the presence and distribution of these organisms in decubital shoulder ulcers (n=51) and ear necroses (n=54) by fluorescence in situ hybridization (FISH) and high-throughput sequencing. In addition, two cases of facial ulcers and five cases of other skin ulcers were included in the study. Samples from all 112 skin lesions and intact skin from pigs without skin ulcers (n=14) were screened by FISH. Three different oligonucleotide probes targeting 16S rRNA were used, specific for domain bacterium, Treponema spp. and species T. pedis. Screening showed that two cases each of facial and other ulcers, 35 (69%) of shoulder ulcers and 32 (59%) of ear necroses were positive for Treponema spp. T. pedis was the unequivocally, predominant species typically constituting more than 90% of the treponemes in a lesion, assessed visually by microscopy. Altogether, T. pedis was demonstrated in 69 of the 71 Treponema spp. positive lesions. We conclude that Treponema spp. are frequently present and abundant in various skin ulcers of pigs. The results from this study point toward an important role of T. pedis as a secondary bacterial infection in porcine skin ulcers, especially in severe and chronic lesions.

Ear necrosis and shoulder ulcers in pigs are animal welfare problems and ethical issues that can cause economic losses for producers. Spirochetes have been observed microscopically in scrapings from pig ulcers since the early 1900s, but have until recently not been cultured and therefore not characterized. In this study, 12 Treponema spp. isolates were acquired from porcine ear necrosis, shoulder ulcers and gingiva. DNA analysis of the 16S rRNA-tRNA(Ile) intergenic spacer region (ISR2) or the 16S rRNA gene revealed relatedness to oral treponemes found in dogs and humans. All isolates except one aligned into two clusters, Treponema pedis and Treponema sp. OMZ 840-like. The 16S rRNA gene of the remaining isolate shared 99% nucleotide identity with Treponema parvum. Genetic fingerprinting of the isolates was performed through random amplification of polymorphic DNA (RAPD). In addition, the isolates were characterized by biochemical tests, including api(®)ZYM, tryptophanase and hippuricase activity, and by testing the antimicrobial susceptibility to tiamulin, valnemulin, tylosin, tylvalosin, lincomycin and doxycycline using broth dilution. All isolates except two showed unique RAPD fingerprints, whereas metabolic activity tests could not differentiate between the isolates. The MICs of all antimicrobial agents tested were low.