Primary skin diseases and cutaneous manifestations of systemic diseases in swine

Swinepox virus: an unusual outbreak in free-range pig farms in Sicily (Italy)

BACKGROUND

Two outbreaks of swinepox were investigated in free-range domestic pig farms located in the northeastern side of Sicily, Italy. The disease is generally self-limiting with a low mortality rate, but morbidity can reach high rates in case of poor sanitary conditions, improper husbandry practices and ectoparasitic infestation. The presented cases are the first ever reported on the island and part of the few cases reported in domestic pigs.

CASE PRESENTATION

Carcasses condemned at the slaughterhouse and deceased pigs from Farm A and Farm B respectively, were referred for post-mortem examination and further investigations, with a strong suspect of SwinePox virus (SWPV) infection. Twelve deceased pigs were examined in total, showing poor body condition and pustular lesions scattered all over the cutaneous surfaces. Moreover, pigs from Farm B showed ocular lesions classified from Grade I to IV (from mild conjunctivitis to severe keratoconjunctivitis with corneal oedema, opacity, and ulcers). Final diagnosis was pursued by the microscopic assessment of skin lesions in both farms, which revealed the typical SWPV-lesion appearance, such as severe and disseminated ulcerative dermatitis and suspected inclusion bodies multifocally observed in the epidermis. Moreover, negative staining Electron Microscopy (nsEM) was performed on skin lesions and ocular swabs from Farm B, revealing in two samples the presence of brick-shaped viral particles, 220 nm long and 160 nm wide, with irregularly arranged surface tubules, identified as SWPV. The gene encoding the 482-bp fragment of the virus late transcription factor-3 was detected by PCR and sequencing revealed 99.79% identity and 100% query-cover with a strain previously isolated in Germany. Field clinical assessment was then performed in Farm B, revealing high overcrowding, poor sanitary conditions and improper husbandry practices, which are relevant risk factors for SWPV transmission.

CONCLUSIONS

The present is the first case report of SWPV in free-range pigs raised in Sicily, an island of the Southern coast of Italy, and wants to raise awareness on a neglected disease, and cause of animal health and welfare issues.

The Role of Vitamins in Mitigating the Effects of Various Stress Factors in Pigs Breeding

Good practices in farm animal care are crucial for upholding animal well-being, efficiency, and health. Pigs, like other farm animals, are exposed to various stressors, including environmental, nutritional, chemical, psychological, physiological, and metabolic stressors, which can disrupt their internal balance and compromise their well-being. Oxidative stress can adversely affect animal performance, fertility, and immunity, leading to economic losses for farmers. Dietary considerations are hugely important in attaining these objectives. This paper reviews studies investigating the impact of additional vitamin supplementation on stress reduction in pigs. Vitamin A can be beneficial in counteracting viral and parasitic threats. Vitamin B can be a potential solution for reproductive issues, but it might also be beneficial in reducing the effects of inappropriate nutrition. Vitamin C plays a vital role in reducing the effects of heat stress or exposure to toxins in pigs. Vitamin D proves to be beneficial in addressing stress induced mostly by infections and weaning, while vitamin E has been shown to mitigate the effects of toxins, heat stress, or transport stress. This review highlights the potential benefits of these dietary antioxidants in maintaining pig health, enhancing productivity, and counteracting the adverse effects of various stressors. Understanding the role of vitamins in pig nutrition and stress management is vital for optimising farm animal welfare and production efficiency.

Auricular and laryngeal chondritis in nursery and finishing pigs

This work aimed to characterize the clinic-pathological presentation of an outbreak of auricular and laryngeal chondritis in pigs. Visits were made to pig farms, where the clinical history was obtained, and clinical and postmortem examinations were performed. In those farms, 3% to 4% of pigs presented otohematomas, which started in the nursery and extended to the finishing phase. Moreover, some finishing pigs presented with respiratory distress, initially characterized as inspiratory dyspnea, associated by an uncommon respiratory stridor and culminating in death. Grossly, nursery piglets had enlarged ears, and on the cut surface, the cartilage was fragmented and associated with blood clots. In the finishing phase, in addition to auricular lesions, the epiglottis and arytenoid cartilages were thickened and distorted, which partially occluded the lumen. Microscopically, the laryngeal and auricular cartilages were fragmented, displayed a loss of matrix basophilia, and were surrounded by lymphohistiocytic inflammatory infiltrate, with occasional multinucleated giant cells and fibrosis. The lesions exclusively affected elastic cartilages. The disease in finishing pigs led to increased mortality and was a differential diagnosis to respiratory challenges. It was not possible to determine the factor that triggered this condition; however, a nutritional association is suspected. To the authors' knowledge, this is the first report of primary auricular and laryngeal chondritis in pigs.