Department of Reproduction, Obstetrics and Herd Health, Faculty of Veterinary Medicine, Ghent University, Merelbeke 9820, Belgium.
Department of Pathology, Bacteriology and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke 9820, Belgium.
Vet J. 2021 May;271:105655. doi: 10.1016/j.tvjl.2021.105655. Epub 2021 Mar 18.
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.
猪耳坏死（PEN）是一种主要发生在集约化养猪生产系统中的疾病，主要影响断奶后的仔猪。该综合征表现为耳尖病变，病变可愈合或加重，导致耳尖部分缺失。该病的发病机制尚不完全清楚。本文描述了 PEN 发展的三种不同假说：（1）葡萄球菌表皮剥脱毒素引起的表皮损伤；（2）小血管阻塞；（3）耳咬，随后β-溶血性链球菌感染。虽然尚未完全阐明风险因素，但已提出病毒和细菌感染以及环境、饲养条件和管理等饲养因素。也有可能某些病例是这些因素的组合。寄生虫感染的作用尚未得到研究。由于细菌感染，严重受影响的猪可以用抗生素治疗。控制和预防措施应侧重于通过实施群体免疫，以及改善卫生条件、饲料质量（考虑到霉菌毒素污染）、管理（适当的饲养密度）和环境条件（例如，饮水器和饲料器的数量和/或最佳通风）来减少潜在的风险因素。需要进一步研究以更好地了解 PEN 的精确病因和发病机制，从而确定风险因素并实施更有针对性的控制措施。
