Individual mutations (e.g. L256F) and polymorphisms in the avr-14B gene, a glutamate-gated chloride channel subunit, have been associated with ivermectin (IVM) resistance in Caenorhabditis elegans and Cooperia oncophora. The aim of the present study was to determine the full-length coding sequence of the avr-14B subunit homologue in Teladorsagia circumcincta and determine the presence/absence o...

Resistance to eprinomectin was suspected in a dairy sheep farm southwestern France. The efficacy of topical and injection formulations against gastrointestinal nematodes (GINs) compared using faecal egg count reduction test. GIN species were identified by real-time PCR, concentrations measured serum High-Performance Liquid Chromatography 2 5 days after treatment. Efficacies 99.6% 86.1% for form...

The effects of condensed tannins (CTs) extracted from pine bark on egg hatching, larval development and the viability of infective L3 larvae of Trichostrongylus colubriformis (Giles, 1892) and Teladorsagia circumcincta (Stadelmann, 1894) (syn. Ostertagia circumcincta) were evaluated using in vitro bioassays. Significant inhibitory effects of CTs were obtained on the viability of the infective l...

Monepantel (MPTL) is one of two new anthelmintic compounds introduced onto the sheep market to control gastro-intestinal nematodes. Resistance to this compound is rare but has been reported. In order to preserve the efficacy of this and other anthelmintics, it is essential to understand both (a) the mechanisms involved in the selection of resistance and (b) how the parasites evolve to deal with...

Gastrointestinal nematodes (GIN) infections are a serious problem in livestock production due to the great economic losses they cause. Their control is increasingly difficult because of rapid development drug resistance and limited number available drugs. Therefore, this study evaluated 18 aminoalcohol 16 diamine derivatives against eggs, first third stage larvae from susceptible resistant isol...

Full-length cDNAs encoding macrophage inhibitory factor-2 (MIF-2) were cloned from Teladorsagia circumcincta (TcMIF-2) and Haemonchus contortus (HcMIF-2). TcMIF-2 HcMIF-2 cDNA (342 bp) encoded proteins of 114 amino acids, each which was present as a single band about 16 kDa on SDS-PAGE. Multiple alignments the protein sequences showed homology 84% between HcMIF-2, 54–76% with MIF-2s seven nemat...

Groups of yearling sheep were trickle infected with Teladorsagia circumcincta for 8 weeks, then the infection cleared with anthelmintic and both these animals and a group of parasite naïve sheep were challenged with 50 000 infective T. circumcincta larvae. The previously infected sheep demonstrated acquired immunity to the parasite, manifested by reduced worm burdens which were evident as early...