Micrometeorological factors involved in development and survival of free-living stages of the sheep nematodes Haemonchus contortus and Trichostrongylus colubriformis. A review

摘要: Temperature and soil moisture are the most important factors affecting development survival ofHaemonchus contortus andTrichostrongylus columbriformis eggs larvae on pasture. More than half of develop into infective in laboratory, but a very low percentage (0.03% forH. contortus) does so There is marked difference betweenH. andT. colubriformis larvae.H. survived winter at Urbana poorly, whereasT. did well. The former better latter spring worse summer, while both equally well fall. Technics for larval recovery from pasture not efficient. Meteorologic conditions ground level where exist quite different those standard weather shelter 1.6 m above ground. Bioclimatographs which mean monthly maximum temperatures plotted against total precipitation fairly good predicting type nematode liable to be given region, they too simplistic relied more approximations.