The effectiveness of anthelmintic treatments given 3 weeks after the onset of rains to control gastrointestinal nematodes in sheep in the highlands of central Kenya was investigated. The study was carried out on a farm situated approximately 85 km north west of Nairobi in Nyandarua District of central Kenya. In May 1999, 35 Corriedale ram lambs aged between 8 and 10 months were eartagged, weigh...

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...

Sixteen calves approximately 6 months old were each infected with 500 metacercariae of Fasciola hepatica. Thirty-two days later they were weighed and divided into two groups, and on day 35 all calves in one of the groups were injected subcutaneously with an ivermectin/closantel combination. Both groups were sacrificed between days 70 and 72 to enable counting and examination of the flukes recov...

RESISTANCE to triclabendazole in field isolates of the liver fluke Fasciola hepatica in sheep was described for the first time by Overend and Bowen (1995) in Australia. In Europe, resistance of F hepatica in sheep to triclabendazole has been reported in Ireland (Lane 1998), Scotland (Mitchell and others 1998), Wales (Thomas and others 2000) and the Netherlands (Moll and others 2000). On the Dut...

In Escherichia coli the Cpx sensor regulator system senses different kinds of envelope stress and responds by triggering the expression of periplasmic folding factors and proteases. It consists of the membrane-anchored sensor kinase CpxA, the response regulator CpxR, and the periplasmic protein CpxP. The Cpx pathway is induced in vivo by a variety of signals including pH variation, osmotic stre...

Two morphologically marked strains of Haemonchus contortus, CAVRS (smooth-macrocyclic lactone resistant) and McMaster (linguiform-macrocyclic lactone susceptible), were used to investigate the selection for anthelmintic resistance following exposure to ivermectin (IVM), a non-persistent anthelmintic. and a more persistent anthelmintic, oral moxidectin (MOX). Three types of selection were invest...