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*stock ingest remaining overwintered L3
 
*stock ingest remaining overwintered L3
 
*strongyle eggs passed out with faeces onto pasture
 
*strongyle eggs passed out with faeces onto pasture
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c) ''Development from egg to L3'':
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*strongyle eggs passed in host faeces for most of the grazing season
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*development of egg to L3 depends on dung-pat microclimate and requires:
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**'''high relative humidity''' (nearly 100%) - dungpat acts as a "buffer" against drought; and
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**'''warmth''' (optimum temperature 25°C) - dungpat cannot buffer against changes in macroclimate temperature.
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*development is therefore influenced largely by '''macroclimate''' and '''temperature'''. Net result = concertina effect.
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d) ''Translation of infective larvae''
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*movement of larvae from dungpat onto grass in order to infect final host
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*L3 must cross a zone of repugnance around the dungpat (up to 45cm) - normally left ungrazed
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*L3 cross zone by swimming in a film of moisture. Also, beetle and earthworm activity, rain splash, soil migration, etc.
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