Krafsur E S, Church C J
J Parasitol. 1985 Jun;71(3):279-86.
The prevalence of developing Thelazia nematodes in face flies (Musca autumnalis) was studied for 7 yr at a beef farm in central Iowa. Juvenile nematodes were not found among flies in reproductive diapause in autumn, nor among nulliparous, overwintered flies in spring, but only among actively reproducing insects. Thus Thelazia probably do not overwinter in face flies. A mean prevalence of 2.0% infected was recorded among flies in 7 fly breeding seasons. No heterogeneity in Thelazia prevalence was detected within fly breeding seasons. The frequency distribution of Thelazia among face flies by year of occurrence was homogeneous, with a mean of 2.75 larval nematodes per infected fly. Thelazia gulosa and T. skrjabini were recovered in necropsy from the eyes of bovines from central Iowa. Prevalence among fat cattle 18-27 mo old was 15%; among cows 3-15 yr old, prevalence was only 3%. Thelazia skrjabini was found in 29 eyes and T. gulosa in 4 eyes. Infections were randomly distributed among the eyes of subject cattle. The mean worm burden was 2.3 T. skrjabini and 12 T. gulosa per infected eye. Thelaziasis is clearly enzootic in Iowa.
在爱荷华州中部的一个养牛场，对厩螫蝇（秋家蝇）体内感染吸吮线虫的患病率进行了为期7年的研究。秋季处于生殖滞育的苍蝇以及春季未产过卵且越冬的苍蝇体内均未发现幼虫期线虫，仅在活跃繁殖的昆虫体内发现了此类线虫。因此，吸吮线虫可能不会在厩螫蝇体内越冬。在7个苍蝇繁殖季节中，记录到苍蝇的平均感染患病率为2.0%。在苍蝇繁殖季节内未检测到吸吮线虫患病率的异质性。按出现年份统计，吸吮线虫在厩螫蝇中的频率分布是均匀的，每只感染苍蝇体内平均有2.75条幼虫期线虫。从爱荷华州中部牛的眼睛尸检中发现了大口吸吮线虫和斯氏吸吮线虫。18至27月龄的肥牛患病率为15%；3至15岁的母牛患病率仅为3%。在29只眼睛中发现了斯氏吸吮线虫，4只眼睛中发现了大口吸吮线虫。感染在受检牛的眼睛中随机分布。每只感染眼睛的平均虫负荷为2.3条斯氏吸吮线虫和12条大口吸吮线虫。吸吮线虫病在爱荷华州显然是地方性流行病。
