一例猪毛首线虫诊断

Diagnosis of a Case of Trichuris suis

摘要: 为明确云南省大理白族自治州某养殖场育肥猪群体性疾病的病因，建立科学防控方案，本试验通过病猪临床诊断、病理剖检、病原学检测及细菌分离鉴定等方法开展系统诊断。结果显示，病猪表现为采食量下降、精神沉郁、顽固性腹泻、渐进性消瘦及贫血等典型症状，抗生素治疗无效；病理剖检可见盲肠和结肠黏膜弥漫性充血、水肿、出血及溃疡，盲肠前端附着大量乳白色线状虫体，虫体前端纤细嵌入黏膜、后部粗短游离于肠腔，呈特征性“马鞭状”；虫体形态学鉴定显示雌虫体长40~55 mm、雄虫30~45 mm且尾端螺旋状卷曲，粪便饱和盐水漂浮法检出大量棕黄色腰鼓形虫卵(50~54 μm × 22~23 μm)，两端具透明栓塞结构；细菌分离鉴定未从心、肝、脾、肾组织中分离出致病菌，排除细菌感染可能。综合上述结果，确诊该猪群感染猪毛首线虫病。试验证实，临床诊断、病理剖检与病原学检测相结合的经典“三板斧”是猪毛首线虫病确诊的核心手段。研究为西南地区猪毛首线虫病的精准诊断与高效防控提供了实践依据和理论参考。

Abstract: To identify the etiology of an epidemic disease in fattening pigs at a farm in Dali Bai Autonomous Prefecture, Yunnan Province, and establish a scientific prevention and control plan, this study conducted systematic diagnosis through clinical diagnosis of sick pigs, pathological necropsy, etiological detection, and bacterial isolation and identification. The results showed that the sick pigs exhibited typical symptoms, including decreased feed intake, depression, refractory diarrhea, progressive emaciation, and anemia, with no response to antibiotic treatment. Pathological necropsy revealed diffuse hyperemia, edema, hemorrhage, and ulceration in the cecal and colonic mucosa. A large number of milky white thread-like parasites were attached to the anterior part of the cecum; the anterior ends of the parasites were slender and embedded in the mucosa, while the posterior parts were thick and short, free in the intestinal lumen, presenting a characteristic “whip-like” shape. Morphological identification of the parasites indicated that female worms were 40~55 mm in length, and male worms were 30~45 mm with spirally curled caudal ends. A large number of brownish-yellow barrel-shaped eggs (50~54 μm × 22~23 μm) with transparent plug-like structures at both ends were detected using the saturated salt solution flotation method. No pathogenic bacteria were isolated from the heart, liver, spleen, or kidney tissues via bacterial isolation and identification, ruling out the possibility of bacterial infection. Based on the above results, the pig herd was diagnosed with swine trichuriasis (infection with Trichuris suis). The study confirmed that the classic “three-step approach”—combining clinical diagnosis, pathological necropsy, and etiological detection—is the core method for confirming swine trichuriasis. This research provides a practical basis and theoretical reference for the accurate diagnosis and efficient prevention and control of swine trichuriasis in Southwest China.