Higuchi T, Taharaguchi S, Hashikura S, Hagiwara S, Gojo C, Satoh S, Yoshida M, Takai S
Hidaka Agriculture Mutual Aid Association, Hokkaido, Japan.
J Am Vet Med Assoc. 1998 Apr 1;212(7):976-81.
To evaluate results of physical and serologic examinations of foals at 30 and 45 days of age on 3 types of farms with various prevalences of clinical disease (endemic, sporadic, none) caused by Rhodococcus equi and to determine whether evaluations were helpful in early diagnosis and control of the disease.
Prospective cohort study.
144 foals at 30 and 45 days of age.
During a 2-year period, 36 foals on farms at which R equi infection was endemic, 71 foals on farms at which the disease was sporadically detected, and 37 foals on farms without the disease were examined by means of auscultation of lungs, serum biochemical and hematologic analyses, and determination of antibody titers against R equi, using ELISA. Transtracheal aspirates were obtained from 14 of 32 foals that had clinical signs of disease and 7 of 41 seropositive foals that did not have clinical signs of disease.
Prevalences of respiratory tract disease and seropositive conversion rates for 45-day-old foals on endemically and sporadically infected farms were significantly higher than on farms without the disease. Rhodococcus equi was isolated from tracheal aspirates of seropositive foals, even when clinical signs were not evident.
Physical and serologic examinations of foals at 30 and 45 days of age were useful for early diagnosis of R equi infection, especially for foals on farms at which the disease was endemic.
评估30日龄和45日龄马驹在3种不同临床疾病患病率（地方流行、散发、无）的农场中进行体格检查和血清学检查的结果，并确定这些评估是否有助于疾病的早期诊断和控制。
前瞻性队列研究。
144匹30日龄和45日龄的马驹。
在2年期间，对地方流行马驹疫感染的农场中的36匹小马驹、偶尔检测到该病的农场中的71匹小马驹以及无该病农场中的37匹小马驹进行了肺部听诊、血清生化和血液学分析，并使用酶联免疫吸附测定法测定抗马驹疫抗体滴度。从32匹有疾病临床症状的小马驹中的14匹以及41匹无疾病临床症状的血清阳性小马驹中的7匹获取气管吸出物。
地方流行和散发感染农场中45日龄马驹的呼吸道疾病患病率和血清阳性转化率显著高于无该病的农场。即使没有明显的临床症状，也从血清阳性马驹的气管吸出物中分离出马驹疫杆菌。
对30日龄和45日龄马驹进行体格检查和血清学检查有助于马驹疫感染的早期诊断，特别是对于疾病地方流行的农场中的马驹。
