Life Sciences Commons^™

Late Fall Transmission Of Nematodirus Battus (Nematoda: Trichostrongyloidea) In Western Oregon, Lora G. Rickard, Eric P. Hoberg, Gary L. Zimmerman, Jannell K. Erno

Harold W. Manter Laboratory of Parasitology: Faculty and Staff Publications

Studies on Nematodirus battusCrofton and Thomas, 1951, have shown a marked seasonality in the pattern of transmission. The life cycle normally involves only one parasitic generation per year. The infective third-stage larvae develop over the summer within eggs deposited on pasture. Eggs are sensitized by low temperatures during fall and winter; larval hatching follows in the presence of adequate moisture and proper osmotic conditions as the temperature rises above 10°C. This set of conditions, conducive to hatching, is regularly present only during spring; thus, hatching of eggs is concentrated into a few weeks during this time. Outbreaks of clinical …