Chenopodium ambrosioides and its essential oil as treatments for Haemonchus contortus and mixed adult-nematode infections in goats

Abstract

The anthelmintic efficacy of Chenopodium ambrosioides oil and fresh material was tested in goats in three trials. In trial 1, 13 adult goats and kids with natural mixed-nematode infections were treated with 0.2 ml of oil/kg body weight (BW). Six adult goats and kids were used as untreated controls. The before- and after-treatment eggs per gram (epg) of feces were compared. In trial 2, 30 kids with pure Haemonchus contortus infections were divided into one of five treatment groups: single doses of the oil at 0.1, 0.2 and 0.4 ml/kg BW, fresh ground plant material or controls. Kids were slaughtered 5–7 days post-treatment and the adult H. contortus were collected from the abomasa. In trial 3, eight kids with pure H. contortus infections were given five daily doses of fresh plant material. Kids were slaughtered 10 days after the last treatment and the number of adult H. contortus collected from the abomasa was compared to that of seven untreated control kids. None of the treatments was effective based on Kruskal–Wallis and Mann–Whitney tests. In addition, in trial 2, the two higher oil doses (0.2 and 0.4 ml/kg BW) caused adverse reactions. Although C. ambrosioides has a long history of use as an anthelmintic in humans and non-ruminants, short-term treatment of individual goats with the plant or oil were not effective in reducing the number of nematode adults or eggs. However, in in vitro tests, the oil did reduce viability of eggs and might be useful as part of a larger long-term ecological strategy to reduce parasite loads at the whole farm level.