Over H J, Koopman J J, Pekelder J J, Gaasenbeek C P
Tijdschr Diergeneeskd. 1977 Mar 1;102(5):303-17.
The effectiveness of the molluscicide N-tritylmorpholine (Frescon, Shell) in the control of fascioliasis was tested in various field conditions. The effect was not only measured by the study of populations of L. truncatula but its use in prevention was also determined by turning tracer lambs out to grass in treated and control field. The studies showed that Frescon applied at the recommended dose rate is a reliable agent, even in the prevention of acute outbreaks of fascioliasis. The preventive effect was found to be most marked on treatment in the spring (preferable to single treatment during the summer), which is of particular importance in view of the fact that infections may occur in the southern Netherlands during the early grazing season.
在各种田间条件下测试了杀螺剂N-三苯甲基吗啉（Frescon，壳牌公司生产）对控制片形吸虫病的效果。不仅通过对截形土蜗种群的研究来衡量其效果，还通过将带有示踪剂的羔羊放到经处理和未经处理的田地里吃草来确定其在预防方面的作用。研究表明，按推荐剂量施用的Frescon是一种可靠的药剂，即使在预防急性片形吸虫病暴发方面也是如此。结果发现，春季处理时预防效果最为显著（优于夏季单次处理），鉴于荷兰南部在早期放牧季节可能发生感染，这一点尤为重要。
