Selection of resistant animals and host immunization have been proposed as alternative methods for the control of gastrointestinal nematode parasites. However, a better knowledge of the mechanisms involved in protective immunity against these parasites is required for the development of optimal strategies. In this study, 3 month old INRA 401 lambs (n = 81) were allocated into three groups: unin...

The prevalence of gastric nematodes in 151 goats on Grand Canary Island is around 56%, with a mean burden of 691 worms/animal. No significant differences of prevalence and intensity were found between the four isoclimatic areas of the island [dry-desert (DD); dry-steppe (DS); temperate-mild (TM); temperate-cold (TC)]. Five nematode species were identified, the most commonly-occurring being Tela...

Acetylcholine receptors are pentameric ligand-gated channels involved in excitatory neuro-transmission in both vertebrates and invertebrates. In nematodes, they represent major targets for cholinergic agonist or antagonist anthelmintic drugs. Despite the large diversity of acetylcholine-receptor subunit genes present in nematodes, only a few receptor subtypes have been characterized so far. Int...

Resistance to natural infections of Haemonchus contortus (wireworm) was studied in Merino sheep. From February 1995 to July 1996 data were collected from the OTK Merino Stud on the farm Wildebeesfontein near Hendrina in Mpumalanga province. From March 1998 to January 2000 another Merino flock at Irene in Gauteng province was included in the study. In both cases, 50 randomly-chosen animals from ...

A cambendazole-resistant (CR) strain of Haemonchus contortus, the large stomach nematode of sheep, had similar in vitro growth characteristics compared to the parent strain (BPL). When the in vitro cultivation system was modified to detect drug resistance: (1) exsheathed infective larvae of the BPL strain did not develop in a culture medium with a concentration of 2.5 /ug/rnl thiabendazole (TBZ...

Due to high prevalence and large pathogenicity, Haemonchus contortus is the main gastrointestinal nematode in tropical subtropical regions. This species responsible for severe economic losses sheep goat breeders Brazil. The control of this parasite currently compromised, mainly, due anthelmintic resistance. In search natural alternatives, Pterogyne nitens, a native Brazilian tree with potential...

Eight five-month-old male lambs received a diet with marginal levels of sodium (0.5 g Na/kg DM); four lambs were given a single dose of infective Haemonchus contortus larvae (4,600 L3/ head) and four were kept uninfected. The lambs were slaughtered 30 days after the infection. Sodium concentration was determined in the abomasal fluid at the slaughter. The balance between intake and faecal excre...

Successful transmission of macroparasites is dependent on exposure of susceptible hosts to free-living infective stages. When these hosts are herbivores that feed mostly on a single food plant then natural selection should favour those infective larvae that selectively ascend this main food plant. Red grouse feed predominantly on heather, Calluna vulgaris, so we predict that the infective larva...

Galectins and collectins are proteins classified in the lectin family that have the ability to recognize molecular patterns associated with pathogens. Studies on cattle have demonstrated high expression of these proteins during infection with gastrointestinal nematodes. The aim of this study was to investigate whether the level of Haemonchus contortus infection would alter the expression of gal...

BACKGROUND Haemonchus contortus causes severe economic losses in small ruminants, so this study was conducted to study the UV effect on H. contortus larvae and its protective effect. METHODS Sixteen male goats were divided into 5 groups, control infected, control uninfected and UV 30 minutes exposure; UV 60 minutes exposure and UV booster 60 minutes exposure. The UV groups were exposed to UV ...