Gastrointestinal nematode infection does not affect selection of tropical foliage by goats in a cafeteria trial

Abstract

It is important to determine whether gastrointestinal nematodes (GINs) affect foliage choice of goats leading to confirm the expression of a self-medication behavior. This study investigated the effect of GIN infection on tropical foliage selection by goats. During experimental stage 1 (10 days), goats had a natural mixed GIN infection, and at stage 2 (10 days), goats were treated with effective anthelmintics to maintain them free of GIN infection. During stage 1 the twelve adult goats (32 ± 2.3 kg live weight [LW]) were assigned to three groups (n = 4) according to their initial GIN infection status: HI group, with fecal egg count (FEC) between 1450 and 2150 eggs per g/feces (EPG); MI group, medium FEC (592-1167 EPG); and the NI group, free from GIN infection. Fresh foliage of four tropical plants were offered to goats ad libitum for 1 h daily: Gymnopodium floribundum (high condensed tannin [CT] content, 37-40 %), Mimosa bahamensis (medium CT content, 16-17 %), Leucaena leucocephala (low CT content, 3-5 %), and Viguiera dentata (negligible CT content, 0.6-0.9 %). Jacobs' selection indexes (JSIs) were estimated for the experimental foliage based on dry matter (DM), CT, or crude protein (CP) intake. During both study stages, individual fecal egg counts were estimated. The JSI patterns of different plant species, based on DM, CT, or CP, were similar irrespective of infection level during stage 1 (HI, MI, and NI) or no GIN infection (stage 2). Thus, irrespective of GIN infection, goats actively selected M. bahamensis (high CT, low CP content) and V. dentata (negligible CT, high CP content) but avoided G. floribundum (high CT, low CP content) and L. leucocephala (medium CT and high CP content). Thus, natural GIN infection did not influence goats' foliage selection.

Anthelmintic activity of plants against gastrointestinal nematodes of goats: a review

“…An anthelmintic product is considered as effective when it has a percentage reduction of over 90% of EPG and adult parasites (Vercruysse et al ., 2001). The treatments with Vigueira dentata , Lespedeza cuneate, Elephantorrhiza elephantina, Gymnopodium floribundum and association of Leucaena leucocephala and Mimosa bahamensis exhibited reduction of EPG over 90%, whereas only one species, A. karroo , induced 90% of reduction of adult nematodes (Marume et al ., 2012; Maphosa and Masika, 2012b; Gujja et al ., 2013; Ventura-Cordero et al ., 2017). Githiori et al .…”

“…An anthelmintic product is considered as effective when it has a percentage reduction of over 90% of EPG and adult parasites (Vercruysse et al, 2001). The treatments with Vigueira dentata, Lespedeza cuneate, Elephantorrhiza elephantina, Gymnopodium floribundum and association of Leucaena leucocephala and Mimosa bahamensis exhibited reduction of EPG over 90%, whereas only one species, A. karroo, induced 90% of reduction of adult nematodes (Marume et al, 2012;Maphosa and Masika, 2012b;Gujja et al, 2013;Ventura-Cordero et al, 2017). Githiori et al (2006) suggest that a lower level of reduction should be established (70%) to the evaluation tests in vivo herbal preparations, since products with moderate anthelmintic activity may be part of an integrated Parasitology program of parasite control in ruminant production systems.…”

Variabilidad en el contenido de polifenoles, actividad biológica y antihelmíntica de extractos metanol:agua de las hojas de Gymnopodium floribundum Rolfe

“…Sin embargo, el presente estudio mostró que existen diferencias en el contenido de TC debidas a la interacción entre edad de hojas y mes de cosecha. La variación en el contenido de TC de hojas de G. floribundum debidas al mes de cosecha ya habían sido sugeridas previamente (1,13,31) . La diferencia en el contenido de TC fue solo evidente entre las hojas EV de marzo (mes de sequía) y junio (mes de lluvias), y de éstas últimas con respecto a las hojas E90 de junio.…”

Selection of Forage Resources by Juvenile Goats in a Cafeteria Trial: Effect of Browsing Experience, Nutrient and Secondary Compound Content

“…By including the learning factor, either through their peers or their mother [1], the goats gain experience and improve the use of available resources. The optimal outcome of experience can be seen as a balanced diet in terms of nutrients and SC to avoid any excesses or deficiencies as well as toxicity risks [34,46,47]. The latter leads to optimizing the nutrient harvest from their diet [48].…”