Three groups of newly-weaned Romney @entity742 were given either a standard oral dose of @entity3753 , a controlled-release capsule containing @entity3753 , or a standard oral dose of moxidectin. At 10, 20, 30 and 40 days after treatment, sub-groups of @entity742 were given 10,000 infective-stage larvae of either a drug-resistant or a drug-susceptible strain of @entity24651 . The recommended oral dose of @entity3753 removed 32 per cent of the resistant strain and over 99.9 per cent of the susceptible @entity24651 . The recommended oral dose of moxidectin removed 91 per cent of the resistant strain and over 99.9 per cent of the susceptible parasites. None of the @entity742 treated with controlled-release capsules was challenged at 20 or 30 days after treatment. Twenty-one days after challenge, samples of faeces were taken to determine the presence of @entity2199 eggs and cultured to establish the proportion of eggs developing to infective-stage larvae (L3). Abomasa were recovered after slaughter and worm burdens determined. In the @entity742 given controlled-release capsules only the resistant parasites were able to establish, and there were significantly fewer than in the @entity742 treated orally with @entity3753 . The proportion of the eggs from resistant parasites which developed to L3 was not reduced by the presence of the capsules. Oral moxidectin provided no protection against the establishment of the resistant strain and viable L3 were recovered after challenge with resistant parasites 10 days after treatment; however, the establishment of susceptible @entity24651 was reduced by more than 99 per cent. The establishment of the susceptible parasites in the @entity742 treated with @entity30635 increased with time and was not significantly lower than in the other groups by 30 days after treatment.

Prophylactic efficacy of persistent anthelmintics against challenge with drug-resistant and susceptible XXXX .

@entity3753 :: ('MESH:D015766', 'Chemical') :: ['albendazole'] @entity24651 :: ('45464', 'Species') :: ['O. circumcincta', 'Ostertagia circumcincta'] @entity2199 :: ('6239', 'Species') :: ['nematode'] @entity742 :: ('9940', 'Species') :: ['lambs'] @entity30635 :: ('MESH:C027837', 'Chemical') :: ['moxidectin']
@entity24651 :: (45464,Species) :: ['Ostertagia circumcincta']
