Ploeg M, Gröne A, Saey V, de Bruijn C M, Back W, van Weeren P R, Scheideman W, Picavet T, Ducro B J, Wijnberg I, Delesalle C
Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands
Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands.
Vet Pathol. 2015 Nov;52(6):1142-7. doi: 10.1177/0300985814556780. Epub 2014 Nov 3.
Megaesophagus appears to be more common in Friesian horses than in other breeds. A prevalence of approximately 2% was observed among Friesian horses presented to the Wolvega Equine Clinic and the Utrecht University Equine Clinic. In this study, morphologic changes in the esophagi of Friesian horses with megaesophagus were compared with those of 6 control horses. Of 18 horses with clinically observed megaesophagus, only 12 animals had esophageal dilation at necropsy, usually involving the thoracic portion. Muscular hypertrophy of the distal esophagus was present in only one-third of the affected horses, indicating that this change is not the most relevant cause of megaesophagus in Friesians. Increased deposition of clumped and disorganized collagen was present in these clinically affected horses mainly in the non-dilated portion of the esophagus. At necropsy, a decrease in neural elements and elastin was present principally in horses with megaesophagus. Mild degeneration and necrosis of the tunica muscularis along the entire length of the esophagus were present in clinically affected horses and encountered only rarely in control animals. There were no significant differences among affected and control horses with respect to inflammation, mineralization, or the number of cells of Cajal. The increased occurrence of megaesophagus in the Friesian breed compared with other horse breeds, together with the presence of abnormal collagen in very young foals, supports the hypothesis that megaesophagus is hereditary in Friesians.
巨食管症在弗里斯兰马中似乎比在其他品种的马中更为常见。在就诊于沃尔韦加马诊所和乌得勒支大学马诊所的弗里斯兰马中，观察到的患病率约为2%。在本研究中，将患有巨食管症的弗里斯兰马的食管形态学变化与6匹对照马的进行了比较。在临床上观察到患有巨食管症的18匹马中，只有12只动物在尸检时有食管扩张，通常累及胸部部分。仅三分之一的患病马匹存在食管远端肌肉肥大，这表明这种变化并非弗里斯兰马巨食管症的最主要原因。在这些临床上患病的马匹中，主要在食管未扩张部分存在聚集和无序排列的胶原蛋白沉积增加。在尸检时，神经元和弹性蛋白的减少主要出现在患有巨食管症的马匹中。临床上患病的马匹食管肌层在整个长度上出现轻度变性和坏死，而在对照动物中很少见。在炎症、矿化或 Cajal 细胞数量方面，患病马匹和对照马匹之间没有显著差异。与其他品种的马相比，弗里斯兰马中巨食管症的发病率增加，以及在非常年幼的驹中存在异常胶原蛋白，支持了巨食管症在弗里斯兰马中具有遗传性的假说。
