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Previous studies have illustrated that different bioactive legume fodders containing condensed tannins might represent one of the options for integrated sustainable control of gastrointestinal nematodes (GIN) in ruminants, which may help address the worldwide development of resistance to synthetic anthelmintics. More recently, impetus has been given to assess the potential antiparasitic activity of less conventional resources, represented by different agro-industrial by-products (AIBPs). This review presents in vitro and in vivo results obtained with a range of tannin-containing AIBPs of various geographical and botanical origins, namely AIBP of nuts, temperate and tropical barks, carob, coffee and cocoa. They tend to confirm the “proof of concept” for their antiparasitic effects and also for other aspects of ruminant production in an agro-ecological context. Socio-economic aspects of the exploitation of such non-conventional resources are also discussed as potential models of the circular economy, by using waste. The different modes of use of these resources are presented in this review, as well as strengths, weaknesses, opportunities, and threats (SWOT) analyses to illustrate the advantages and limitations of on-farm use.

Acacia nilotica var adansonii (Guill. et Perr.) O. Ktze and Acacia raddiana (Savi) species are local ressources important to feed animals in Sahelian area of Burkina Faso. Thus, this experiment was to investigate the in vitro effect of both Acacias on ruminal fermentation, CH4 production and rumen microbial community using a semi-automatic system. In all experiments, 25 mL of the inoculum solution was incubated with 50 mL of buffered rumen fluid at 39 °C and gas production was measured at 2, 4, 8, 12 and 24 h. The results show that A. nilotica was rich in condensed tannins and fiber content compared to A. raddiana which was rich in total tannins. A. raddiana treatment presented greater degradability of organic matter and lower CH4 production compared to A. nilotica and control group (P0.05). We conclude that A. nilotica leaves showed negative effect on ruminal fermentation due to high fiber and CT content, and A. raddiana could be an interesting plant to increase fiber digestion and reduce CH4 production in vitro.

This study assessed the ultrastructural changes caused in adult Haemonchus contortus obtained from goats fed fodder based on polyphenol-rich plants Lysiloma latisiliquum or Onobrychis viciifolia or from goats drenched with quebracho extract, Schinopsis spp. The H. contortus were obtained from artificially infected goats used as models to investigate the anthelmintic effect of feeding or drenching with the polyphenol-rich materials. Nematode populations were exposed to polyphenol-rich plant materials by feeding host goats for 8 consecutive days (D28 to D35 post-infection) with (a) L. latisiliquum fodder at 800 g fresh basis/day, (b) O. viciifolia fodder offered ad libitum, and (c) drenched with a solution containing quebracho extract (90 g/day). Meanwhile, control H. contortus were obtained from goats fed polyphenol-free diets. The H. contortus specimens were recovered from the goats on D36 post-infection, and transmission electron microscopy (TEM) was used to identify ultrastructural changes. In vivo exposure to different polyphenol-rich plant materials caused vacuolization of the nematodes’ intestinal, muscular and hypodermal cells. These alterations represent the first evidence of cell damage caused in H. contortus when hosts were fed or drenched with polyphenol-rich materials. Ultrastructural changes affecting several types of cells could explain modifications in worm motility and nutrition, eventually affecting H. contortus reproductive success. This study contributes to our understanding of the mechanisms of action of polyphenol-rich plants against H. contortus when given as nutraceuticals to goats.

Gastrointestinal nematodes are a major threat to small ruminant rearing in the Sahel area, where farmers traditionally use bioactive plants to control these worms, including Acacia nilotica and Acacia raddiana. The main aim of this study was to screen the potential anthelmintic properties of aqueous and acetone extracts of leaves of these two plants based on three in vitro assays: (1) the egg hatch inhibition assay (EHA); (2) the larvae exsheathment inhibition assay (LEIA) using Haemonchus contortus as a model; and (3) an adult mortality test (AMT) applied on Caenorhabditis elegans. For the EHA, only A. raddiana was effective with IC50 = 1.58 mg/mL for aqueous extract, and IC50 = 0.58 mg/mL for acetonic extract. For the LEIA, all extracts inhibited the exsheathment of larvae compared to the controls, and the aqueous extract of A. nilotica was more larvicidal with IC50 = 0.195 mg/mL. In general, all responses to the substances were dose-dependent and were significantly different from the control group (p

Gastrointestinal nematodes (GIN) infections, commonly called 'worms', affect both humans and animals. In veterinary medicine, the search for alternatives to control GIN is now considered a priority because of increasing resistances to commercial anthelmintics. The use of bioactive plants and related secondary metabolites is one of these alternatives. This study aimed to collect data on the use of medicinal plants (MPs) for humans and veterinary practices and at listing plant species with potential anthelmintic properties to select some plant species for further studies following three criteria (availability, originality and popularity). A cross sectional survey was conducted with a total of 384 participants, using semistructured face-to-face interviews and a free list. To evaluate quantitative data of MPs, two ethnobotanical indices were calculated, the Salience index (SI) and the Use Value (UV). The importance and use of MPs in the population of study was high, 98% (372/383) of participants reported use MPs and 86% (321/384) mentioned knowledge of MPs used against GIN. The transmission of knowledge is not limited to the family environment. Sixteen plant species were listed belonging to 10 botanical families. The Asteraceae was the most popular botanical family. Six plants species were indicated for veterinary use. The four MPs selected for furthers studies were, namely: Kyllinga odorata Valh. (Cyperaceae), Cassia occidentalis L. (Fabaceae), Artemisia absinthium L. (Asteraceae), Verbena litoralis Kunth. (Verbenaceae). Evaluation of those MPs based on in vitro and in vivo assays are planned to validate the traditional local knowledge of these 4 plants. [ABSTRACT FROM AUTHOR]

Strategies to reduce dependence on synthetic drugs for the treatment of gastrointestinal nematodes (GIN) infections in ruminants include the search for novel anthelmintic scaffolds on plants, yet salt-tolerant plants remain overlooked. This study aims to evaluate the in vitro anthelmintic properties of selected salt-tolerant plants against GIN, and identify the potential bioactive secondary metabolites involved. For that purpose, 80% acetone/water extracts were prepared from dried biomass of aerial organs of nine salt-tolerant plant species and tested against Haemonchus contortus and Trichostrongylus colubriformis by the Larval Exsheathment Inhibition Assay (LEIA) and Egg Hatching Inhibition Assay (EHIA). Pistacia lentiscus, Limoniatrum monopetalum, Cladium mariscus and Helychrisum italicum picardi were the most active in both GIN and life stages. To investigate the role of polyphenols in the anthelmintic activity, four selected extracts were treated with polyvinylpolypyrrolidone (PVPP), and non-treated and treated samples were further characterized by high-performance liquid chromatography with electrospray ionization mass spectrometric detection (HPLC-ESI-MSn). While polyphenols seem responsible for the EHIA properties, they are partially accountable to LEIA results. Several phenolics involved in the anthelmintic effects were identified and discussed. In sum, these species are rich sources of anthelmintic compounds and, therefore, are of major interest for nutraceutical and/or phytotherapeutic applications against GIN in ruminants. [ABSTRACT FROM AUTHOR]