In vitro and in vivo anthelmintic properties of Caesalpinia coriaria fruits against Haemonchus contortus

The purpose of the present study was to assay the in vitro and in vivo anthelmintic activity (AA) of Caesalpinia coriaria (Cc) mature fruits against the nematode Haemonchus contortus (Hc). The Hc infective larvae were used to assess the in vitro AA through larval mortality assay. The exposure of larvae to the different treatments was performed in 96-well microtitration plates. The treatments were as follows: hydroalcoholic extract (HA-E, at 25-100 mg/mL), aqueous fraction (Aq-F, at 12.5-50 mg/mL), organic fraction (EtOAc-F at 12.5-50 mg/mL), compounds (1, methyl gallate and 2, gallic acid at 1.25-10 mg/mL), positive control (ivermectin at 5 mg/mL) and two negative controls (distilled water and 4% methanol). After exposure, dead and live larvae were quantified and results were compared to their controls. The in vivo assay was carried out by a faecal egg count reduction test (FECRT); artificially infected goat kids (F1: Boer x Nubia) were treated with Cc ground dried fruits to assess the AA. The treatments were established as follows: G1-untreated goats (negative control), G2-goats dewormed with ivermectin (positive control), G3-goats fed with Cc mature fruits (10% of their diet). Results in both in vitro and in vivo assays were analysed using an ANOVA through random design, applying a general linear model and mixed models. The in vitro results showed an evident larvicidal effect of the HA-E, EtOAc-F from Cc, indicating that the compound responsible for the AA was gallic acid. The results of the in vivo study corroborated the anthelmintic properties of Cc, reaching 78.6% reduction in the elimination of Hc eggs per gram of faeces. This plant represents a potential natural anthelmintic for the control of haemonchosis in goats under grazing conditions. Future studies should standardise the Cc extract or dried fruits for use in the management of nematodiasis in goat herds.