THE EFFECT OF FARM-MANAGEMENT STRATEGIES ON THE INCIDENCE OF SHEEP STRIKE IN BRITAIN - A SIMULATION ANALYSIS

A deterministic model is used to simulate the seasonal incidence of sh eep myiasis (strike) on farms in Britain and to explore the effects of different farm management strategies on strike incidence. The model i s based on two sub-components: the seasonal pattern of abundance of th e primary agent of sheep myiasis in northwest Europe, the blowfly Luci lia sericata and the range of factors known to influence ewe and lamb susceptibility to strike. The results of these simulations show that f amiliar farm management strategies, such as shearing, reduction in sco uring caused by endoparasitic worms and insecticide use can have an im portant role in the reduction of strike incidence in ewes and lambs. H owever, the effectiveness of these techniques can be highly dependent of their timing in relation to seasonal changes in blowfly abundance a nd the effects of temperature and rainfall. (C) 1998 Elsevier Science B.V. All rights reserved.