In Vitro Ovicidal Effect of Common Juniper (Juniperus communis L.) Essential Oil on Sheep Gastrointestinal Nematodes

Abstract

The negative influence of gastrointestinal parasitism in sheep is growing today due to the development of anthelmintic resistance to commercial drugs. For this reason, researchers around the world are looking for new, alternative strategies for controlling these parasites. In this context, medicinal plants and their products are increasingly mentioned. The aim of this study was to evaluate in vitro ovicidal activity of common juniper (Juniperus communis L.) essential oil against sheep gastrointestinal nematodes. For that purpose, the egg hatch test was used, and the obtained results were analyzed by analysis of variance (ANOVA) followed by comparison with Tukey’s test (p<0.05). Faecal samples were collected from two independent, natural-infected farms located in Eboli (SA), Italy, whereby the coproculture examination identified the presence of four genera of sheep gastrointestinal nematodes: Haemonchus (53%), Trichostrngylus (29.5%), Teladorsagia (14.5%) and Chabertia (3%). Main components of common juniper essential oil identified by GC-MS analysis were α-pinene (40.46%), sabinene (14.04%), myrcene (8.87%) and limonene (4.95%). In vitro ovicidal activity was evaluated at six different concentrations (50, 12.5, 3.125, 0.781, 0.195 and 0.049 mg/mL), whereby J. communis essential oil showed high activity with the inhibitory effect on hatchability of 81-96.75%, depending on the concentration. For all concentration tested, the effect was statistically significantly higher compared to the negative control, while for the three highest concentrations the effect was similar to the positive control. The obtained results suggested that J. communis essential oil have high anthelmintic potential. However, these results need confirmation in further field examination.

Negativni uticaj gastrointestinalnih parazita kod ovaca u današnje vreme raste usled razvoja antihelmintičke rezistencije na komercijalne preparate. Iz tog razloga, istraživači širom sveta tragaju za novim, alternativnim strategijama u cilju kontrole ovih parazita. U tom kontekstu, lekovite biljke i njihovi proizvodi se sve češće spominju. Cilj ovog istraživanja je bio ispitati in vitro ovicidnu aktivnost esencijalnog ulja kleke (Juniperus communis L.) protiv gastrointestinalnih nematoda ovaca. Za ovu svrhu je upotrebljen egg hatch test, nakon čega su dobijeni rezultati obrađeni analizom varijanse i potom upoređeni Tukijevim testom (p<0.05). Uzorci fecesa su uzeti sa dve odvojene farme koje se nalaze u oblasti Eboli (SA), Italija, pri čemu je tokom ispitivanja koprokulture identifikovano prisustvo četiri roda gastrointestinalnih nematoda ovaca: Haemonchus (53%), Trichostrongylus (29.5%), Teladorsagia (14.5%) i Chaberita (3%). Najzastupljenije komponente etarskog ulja kleke identifikovane biohemijskim analizama su bile α-pinen (40.46%), sabinen (14.04%), mircen (8.87%) i limonen (4.95%*). In vitro ovicidna aktivnost je testirana za šest različitih koncentracija (50, 12.5, 3.125, 0.781, 0.195 i 0.049 mg/mL), pri čemu je etarsko ulje kleke pokazalo visoku aktivnost sa inhibitornim efektom na izleganje larvi od 81-96.75%, u zavisnosti od koncentracije. Kod svih ispitivanih koncentracija efekat je bio statistički značajno veći u poređenju sa negativnom kontrolom, dok je kod tri najveće koncentracije efekat bio sličan pozitivnoj kontroli. Dobijeni rezultati ukazuju na to da etarsko ulje kleke ima visok antihelmintički potencijal. Međutim, potrebno je ove rezultate potvrditi u budućim ispitivanjima u terenskim uslovima.