Infections with Haemonchus contortus are a major constraint on ruminant health world-wide. Young lambs are very sensitive to Haemonchus infection. Older lambs and sheep acquire immunity after a continuous or seasonal exposure to the parasite. The mechanisms underlying immunity are still not completely understood. Antibodies, in particular local IgA and IgE, certainly play a role. The role of Ig...

While there is some evidence that changes in nicotinic acetylcholine receptor (nAChR) subunits confer resistance to levamisole in gastrointestinal helminth parasites, the exact nature of the resistance mechanism(s) is unclear. We utilised the presence of a resistant fraction within the Wallangra 2003 isolate of Haemonchus contortus larvae in order to subdivide the population into three subpopul...

Controlled-release albendazole capsules (CRCs) are currently registered for use in Australia and New Zealand as anthelmintic treatment in sheep. However, reports on the efficacy of such products on resistant parasite populations are sometimes controversial. This is the first study to report on the efficacy of such products under South African field conditions in sheep harbouring a population of...

Helminthiasis or infection with gastrointestinal nematodes such as Haemonchus contortus is a common problem in grazing animals which can lead to poor animal performance and economic loss to the livestock industry (Waller & Thamsborg, 2004). In Malaysia, the main methods of controlling gastrointestinal nematodes is using chemical anti-parasitic drug or anthelmintic and also by maintaining good p...

A group of 12 10-month-old, worm-free Merino lambs were given a single injection of disophenol at 10 mg/kg. This group and another group of 12 worm-free lambs were infested with infective larvae of Haemonchus contortus 1-3 times a week with a maximum dose of 4000/week from 0-91 days. From 95-168 days the dose was increased to a maximum of 6000/week. Every 7 days faeces were examined for worm eg...

The phase II detoxification system glutathione transferase (GST) is associated with the establishment of parasitic nematode infections within the gastrointestinal environment of the mammalian host. We report the functional analysis of a GST from an important worldwide parasitic nematode of small ruminants, Haemonchus contortus. This GST shows limited activity with a range of classical GST subst...

Haemonchus contortus is a species of gastrointestinal strongyles of primary concern for sheep. This highly pathogenic, blood-feeding helminth negatively influences animal health, welfare and productivity. In order to elucidate the current scenario in terms of prevalence and intensity of H. contortus infection in sheep farms across Europe, a standardized crosssectional survey was conducted in th...

Fortes F.S., Kloster F.S., Schafer A.S., Bier D., Buzatti A., Yoshitani U.Y. & Molento M.B. 2013. Evaluation of resistance in selected field strain of Haemonchus contortus to ivermectin and moxidectin using the Larval Migration on Agar Test. Pesquisa Veterinária Brasileira 33(2):183-187. Laboratório de Doenças Parasitárias, Universidade Federal do Paraná, Rua dos Funcionários 1540, Curitiba, PR...