Abstract

The aim of this study was to explore sources of paddock and laboratory variability in parasitic third stage larval (L3) tests. Recovery of Teladorsagia circumcincta larvae was greater than Trichostrongylus colubriformis larvae recovery from water (60 vs 43%; P <0.005), from water contaminated with soil (55 vs 36%; P <0.03) and from water with pasture (27 and 6%; P <0.001). Recoveries following seeding with either T. circumcincta or T. colubrifomis L3s onto pasture were similar (44% vs 56% respectively). Naturally contaminated pasture samples had similar mean larval number (larvae/kg DM) following extraction using either the plastic bag method (566) or Baermanns extraction (533). Pasture plucking to ground level 50, 100, 150 or 300 times had L3s 1,390 (range 406 - 3,846), 1250 (0 - 4,878), 360 (0 - 1,069) and 450 (182 - 742)/kg DM respectively (P

AJ, Litherland, and DL Deighton

Proceedings of the New Zealand Society of Animal Production, Volume 68, Brisbane, Australia, 124-127, 2008