In Vivo Effects of Fagara Leaves on Sheep Infected with Gastrointestinal Nematodes

Abstract

Infections of the gastrointestinal tract with parasitic nematodes, and particularly Haemonchus contortus, represent one of the main pathological constraints on the breeding of small ruminants in tropical countries. Owing to the constant development of anthelmintic resistance in worm populations, alternative control methods are being evaluated, including an assessment of the value of the traditional plants. The effect of the consumption of Fagara leaves on sheep infected with gastrointestinal nematodes was therefore measured both under controlled conditions and in a field survey. In sheep experimentally infected with 2500 third-stage larvae of H. contortus, a three-day administration of Fagara was associated with a decrease in egg excretion and a significant reduction in the fertility of female worms, without changes in the worm number. A reduction in egg output was also confirmed from the results obtained of a survey or naturally infected sheep performed in smallholder farms. This survey also indicated that the repeated consumption of small amounts of Fagara leaves was more effective than a single three-day administration. Results of both studies suggest that Fagara leaves might be an alternative option to chemotherapy to modulate the epidemiology of H. contortus in tropical countries.

Extracts from the bark of Fagara heitzii (Aubr. et Pel.) (Rutaceae) tree are toxic to two weevils and the American cockroach

“…The medicinal and insecticidal properties of other species of the Rutaceae family including Citrus, Xanthoxylum and Clausena have been reported (Bowden & Ross 1963;Su et al 1972;Kubo et al 1984;Adesina 1986;Haubruge et al 1989;Blade 1990;Dales 1996;Don Pedro 1996;Oluronke et al 1999;Ouattara et al 2004;Hounzangbe-Adoté et al 2005).…”

Discovery of quantitative trait loci for resistance to parasitic nematode infection in sheep: I. Analysis of outcross pedigrees

“…As a result of this failure of anthelmintic drenches, a major research effort has been underway for the past 15 years to examine alternatives to chemical control. The use of nematode trapping fungi [ 6 ], diets high in condensed tannins [ 7 , 8 ], and other plant materials [ 9 ] as well as other nutritional approaches [ 10 , 11 ] have all been examined as possible approaches to reduce the impact of nematode parasites in sheep.…”

Medicinal plants for helminth parasite control: facts and fiction

“…Iqbal et al (2004) demonstrated that the consumption of the whole plant resulted in a 62% reduction of the abomasal nematode Haemonchus contortus egg counts. The consumption of fagara leaves (Zanthoxylum zanthoxyloides), a native tree from Africa, believed to have antiparasitic activity, resulted in reduced egg excretion by the same nematode in sheep, when consumed regularly in small amounts (Hounzangbe-Adote et al, 2005). Similarly, lespedeza (Sericea lespedeza), a grazing perennial legume native of Eastern Asia showed promising anthelmintic activity when offered to goats either fresh (Min et al, 2004) or as hay (Shaik et al, 2004;Lange et al, 2006).…”