The effect of dexamethasone on resistance of older lambs to infection with Nematodirus battus

Journal of Helminthology
M D WinterD L Lee

Abstract

Old lambs (8 months of age) infected with 50,000 L3 of Nematodirus battus had larvae developing normally in their tissues on day 4 post-infection (P.I.), but by day 8 P.I. there were only 4105 +/- 1044 worms left in the alimentary tract. Some of these worms contained crystals in their intestine. Eight-month-old lambs treated with dexamethasone and infected with 50,000 L3 of N. battus contained a mean worm burden of 7878 +/- 1262 on 18 days P.I. Untreated 8-month-old lambs similarly infected were virtually worm free by day 18 P.I. Peripheral eosinophilia became elevated in the untreated lambs over the course of infection and, at post-mortem, the tissue mast cell and eosinophil counts were much higher than in the dexamethasone treated group. Although the phenomenon of age resistance is thought to have a strong immunological component, there may also be other physiological factors, resulting in fewer nematodes and lower fecundity of the worms.

References

Apr 1, 1989·International Journal for Parasitology·T L Rothwell
Apr 1, 1972·Parasitology·C J Mapes, R L Coop
Oct 1, 1981·International Journal for Parasitology·D B Adams, K J Beh
Jun 1, 1995·International Journal for Parasitology·D L Emery, S J McClure
Jun 1, 1994·Veterinary Parasitology·M CuquerellaJ M Alunda

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Citations

Oct 12, 2000·International Journal for Parasitology·M D WinterD L Lee
Oct 17, 2002·Trends in Parasitology·Mike D Winter
Oct 28, 2017·Irish Veterinary Journal·Connor McMahonIan Fairweather

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